U.S. patent application number 16/008926 was filed with the patent office on 2018-12-20 for molding material, molding method using same, method for producing molding material, and method for producing fiber-reinforced composite material.
This patent application is currently assigned to Toray Industries, Inc.. The applicant listed for this patent is Toray Industries, Inc.. Invention is credited to Masato Honma, Shunsuke Horiuchi, Naokichi Imai, Atsuki Tsuchiya, Kohei Yamashita, Koji Yamauchi.
Application Number | 20180362760 16/008926 |
Document ID | / |
Family ID | 47422620 |
Filed Date | 2018-12-20 |
United States Patent
Application |
20180362760 |
Kind Code |
A1 |
Imai; Naokichi ; et
al. |
December 20, 2018 |
MOLDING MATERIAL, MOLDING METHOD USING SAME, METHOD FOR PRODUCING
MOLDING MATERIAL, AND METHOD FOR PRODUCING FIBER-REINFORCED
COMPOSITE MATERIAL
Abstract
Provided is a molding material which includes a composite of 1
to 50 wt % of a continuous reinforcing fiber bundle (A) and 0.1 to
20 wt % of a poly(phenylene ether ether ketone) oligomer (B); and
30 to 98.9 wt % of a thermoplastic resin (C) adhering to the
composite, wherein the component (B) has a melting point of not
higher than 270.degree. C. Also provided are a method for molding
the molding material, a method for producing the molding material,
and a method for producing a fiber-reinforced composite material. A
molded article having high heat resistance and dynamic properties
can be easily produced without impairing the economic efficiency
and productivity during the process for producing a molding
material. In addition, a fiber-reinforced composite material can be
produced with more ease and high productivity.
Inventors: |
Imai; Naokichi; (Iyo-gun,
JP) ; Tsuchiya; Atsuki; (Iyo-gun, JP) ; Honma;
Masato; (Iyo-gun, JP) ; Yamashita; Kohei;
(Nagoya-shi, JP) ; Horiuchi; Shunsuke;
(Nagoya-shi, JP) ; Yamauchi; Koji; (Nagoya-shi,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Toray Industries, Inc. |
Tokyo |
|
JP |
|
|
Assignee: |
Toray Industries, Inc.
Tokyo
JP
|
Family ID: |
47422620 |
Appl. No.: |
16/008926 |
Filed: |
June 14, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14128868 |
Dec 23, 2013 |
10023737 |
|
|
PCT/JP2012/065701 |
Jun 20, 2012 |
|
|
|
16008926 |
|
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|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08J 2471/12 20130101;
B29B 15/12 20130101; B29C 70/48 20130101; C08J 2381/04 20130101;
B29C 70/521 20130101; C08J 2377/00 20130101; C08J 5/042 20130101;
C08L 71/08 20130101; C08J 2379/08 20130101; B29C 70/40 20130101;
B29C 70/30 20130101; C08J 5/04 20130101; B29B 15/127 20130101; C08J
2371/12 20130101 |
International
Class: |
C08L 71/08 20060101
C08L071/08; B29B 15/12 20060101 B29B015/12; B29C 70/48 20060101
B29C070/48; B29C 70/52 20060101 B29C070/52; B29C 70/30 20060101
B29C070/30; B29C 70/40 20060101 B29C070/40; C08J 5/04 20060101
C08J005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 24, 2011 |
JP |
2011-140689 |
Jun 24, 2011 |
JP |
2011-140690 |
Jun 24, 2011 |
JP |
2011-140691 |
Jun 24, 2011 |
JP |
2011-140692 |
Jun 24, 2011 |
JP |
2011-140693 |
Claims
1. A molding material comprising a reinforcing fiber substrate
(A'), a poly (phenylene ether ether ketone) oligomer (B), and a
polymerization catalyst (D), wherein the component (B) has a
melting point of not higher than 270.degree. C.
2. The molding material according to claim 1, wherein the component
(B) comprises a cyclic poly (phenylene ether ether ketone) in an
amount of 60 wt % or more.
3. The molding material according to claim 1, wherein the component
(B) is a mixture of cyclic poly (phenylene ether ether ketone)s
having different numbers of repeating units (m).
4. The molding material according to claim 1, wherein the component
(A') is a carbon fiber.
5. The molding material according to claim 1, wherein the content
of the component (A') is 30 wt % or more.
6. The molding material according to claim 1, wherein the content
of the component (D) is 0.001 to 20 mol % per 1 mol of ether ether
ketone structural unit in the component (B).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S.
application Ser. No. 14/128,868, filed Dec. 23, 2013, which is the
U.S. National Phase application of PCT/JP2012/065701, filed Jun.
20, 2012, and claims priority to Japanese Patent Application No.
2011-140689, filed Jun. 24, 2011, Japanese Patent Application No.
2011-140690, filed Jun. 24, 2011, Japanese Patent Application No.
2011-140691, filed Jun. 24, 2011, Japanese Patent Application No.
2011-140692, filed Jun. 24, 2011, Japanese Patent Application No.
2011-140693, filed Jun. 24, 2011, the disclosures of each of these
applications being incorporated herein by reference in their
entireties for all purposes.
FIELD OF THE INVENTION
[0002] The present invention relates to a molding material that is
excellent in productivity, handleability, and moldability and
provides a molded article having excellent dynamic properties, a
molding method using the same, a method for producing the same, and
a method for producing a fiber-reinforced composite material
excellent in economic efficiency and productivity.
BACKGROUND OF THE INVENTION
[0003] Various forms of molding materials comprising a continuous
reinforcing fiber bundle and a thermoplastic resin as a matrix are
known; for example, thermoplastic prepregs, yarn, and glass mats
(GMT). Such molding materials are characterized in that they are
easy to mold because of the properties of thermoplastic resin; they
are free from the burden of storage unlike thermosetting resins;
and the resulting molded article have high toughness, so that it is
excellent in recyclability. In particular, pelleted molding
materials can be applied to molding methods that are excellent in
economic efficiency and productivity such as injection molding and
stamping molding, and are useful as industrial materials.
[0004] However, for impregnating a thermoplastic resin into a
continuous reinforcing fiber bundle during the process for
producing a molding material, such molding materials are
disadvantageous in terms of economic efficiency and productivity,
and therefore are not so widely used at present. For example, it is
well known that impregnation of a resin into a reinforcing fiber
bundle becomes difficult as the melt viscosity of the resin
increases. In particular, thermoplastic resins having excellent
dynamic properties such as toughness and ductility are
high-molecular-weight, have a high viscosity compared to those of
thermosetting resins, and require a higher process temperature.
Thus, such thermoplastic resins have been unsuitable for producing
a molding material easily with high productivity.
[0005] When a low-molecular-weight, i.e., low-viscosity
thermoplastic resin is used as a matrix resin because of ease of
impregnation, there is a problem in that the resulting molded
article will have significantly decreased dynamic properties.
[0006] Further, as fiber-reinforced composite materials come to be
used in harsher environments, higher heat resistance have been
required for a matrix resin.
[0007] Under such circumstances, the presence of a
low-melting-point and low-molecular-weight thermoplastic resin was
not preferred because it caused deformation of a molded article
under high-temperature conditions. Consequently, molding materials
comprising a thermoplastic resin excellent in impregnation
properties and heat resistance have been demanded.
[0008] Fiber-reinforced composite materials comprising a
reinforcing fiber and a matrix resin are lightweight, can provide
excellent strength properties, and can be designed to have any
strength by controlling their fiber orientation. Therefore, such
fiber-reinforced composite materials are widely used, for example,
in sports applications such as golf shafts and fishing rods,
aerospace applications such as aircraft parts and artificial
satellite parts, and general industrial applications such as
automobiles, marine vessels, electrical and electronic equipment
housings, robot parts, windmills, tanks, bathtubs, and helmets. In
producing a fiber-reinforced composite material, production methods
in which prepregs used as intermediate substrates are laminated to
form a laminate, the prepregs being obtained by impregnating
reinforcing fibers with a matrix resin, are widely used because, in
general, high fiber content is easily achieved and handling is
relatively easy. As a matrix resin to be impregnated into
reinforcing fibers in a prepreg, thermosetting resins such as
unsaturated polyester resins, vinyl ester resins, and epoxy resins
are often used because of the ease of impregnation into a fiber
bundle, but the thermosetting resins become an insoluble and
infusible polymer having a three-dimensional network structure via
curing. Such a polymer is difficult to recycle, and a disposal
problem becomes more serious.
[0009] As a thermoplastic matrix resin used for a prepreg, various
resins such as polyethylene, polyester, polyamide, and
polycarbonate are, used. In applications that require high
performance, such as aerospace applications, polyether ether
ketone, polyetherimide, polyphenylene sulfide, and the like that
are excellent in heat resistance, chemical resistance, and
mechanical properties are suitably used.
[0010] However, such a thermoplastic resin prepreg has problems in
that, in a production process for impregnating a fiber bundle with
a matrix resin, a high temperature and a high pressure are required
because of its high molecular weight compared to those of
thermosetting resins; it is difficult to produce a prepreg having
high fiber content; and a prepreg produced has so many
unimpregnated parts that sufficient mechanical properties cannot be
provided.
[0011] Fiber-reinforced composite materials comprising a continuous
reinforcing fiber substrate and a matrix resin are lightweight and
have excellent dynamic properties, and they are widely used in
sports equipment applications, aerospace applications, general
industrial applications, and the like. In particular, composite
materials comprising a carbon fiber as a reinforcing fiber (CFRP)
have a specific strength and specific rigidity that are superior to
those of metal materials, and the amount thereof used is increasing
mainly in aerospace applications. As a matrix resin, thermosetting
resins have hitherto been preferably used because of their
satisfactory impregnation into a reinforcing fiber substrate.
Thermoplastic resins have been unsuitable for producing a molding
material easily with high productivity because they are
high-molecular-weight, have a high viscosity compared to those of
thermosetting resins, and require a higher process temperature.
[0012] However, composite materials comprising a thermoplastic
resin as a matrix resin have received attention in recent years for
reasons that such composite materials can be molded in a short
time; the resulting molded article is recyclable; and they are
excellent in post-processability such as thermal adhesion and
thermal reformation.
[0013] Further, fiber-reinforced composite materials comprising a
reinforcing fiber and a matrix resin allows material design taking
advantages of the reinforcing fiber and the matrix resin, and,
consequently, their use is expanding to the aerospace field,
transport equipment/industrial machine field, civil engineering and
construction field, sports/leisure field, and the like.
[0014] As a reinforcing fiber, glass fiber, aramid fiber, carbon
fiber, boron fiber, and the like are used. As a matrix resin, both
thermosetting resin and thermoplastic resin are used, but
thermosetting resin, which readily impregnates into a reinforcing
fiber, is often used. However, fiber-reinforced composite materials
comprising a thermosetting resin have problems in that the
productivity is low because a long time is required for heat curing
and that the pot life of a prepreg is restricted.
[0015] In contrast, fiber-reinforced composite materials comprising
a thermoplastic resin as a matrix have been put to practical use
for reasons that the productivity is high because such
fiber-reinforced composite materials do not need curing reaction
and that they are easily welded, repaired, and recycled.
PATENT DOCUMENTS
[0016] Patent Document 1 discloses a method for producing a molding
material in which in order to easily impregnate a thermoplastic
resin into a continuous reinforcing fiber bundle, a
low-molecular-weight thermoplastic resin is impregnated, and then
the resultant is integrated with a high-molecular-weight
thermoplastic resin.
[0017] Patent Document 2 discloses a molding material comprising a
high-molecular-weight thermoplastic resin and a composite of
polyarylene sulfide prepolymer and continuous reinforcing fibers,
the high-molecular-weight thermoplastic resin being configured to
be in contact with the composite. Polyarylene sulfide prepolymer is
an excellent material because it easily impregnates into a
reinforcing fiber bundle and, therefore, increases the productivity
of a molding material, and, in addition, it is readily dispersed or
dissolved in a matrix resin in a molding process to enhance the
dispersion of reinforcing fibers into a molded article.
[0018] Patent Document 3 discloses a molding material comprising a
high-molecular-weight thermoplastic resin and a composite of
high-molecular-weight polyarylene sulfide and continuous
reinforcing fibers, the high-molecular-weight thermoplastic resin
being configured to be in contact with the composite. This document
describes a method for producing a molding material with high
productivity in which a polyarylene sulfide prepolymer having a low
melt viscosity is impregnated into reinforcing fibers and then
polymerized into high-molecular-weight polyarylene sulfide. In
addition, since the polyarylene sulfide in the molding material is
high-molecular-weight, the molding material provides a molded
article with excellent heat resistance.
[0019] Patent Document 4 discloses a cyclic poly (aryl ether)
oligomer, a method for producing the same, and a method for
polymerizing the cyclic poly (aryl ether) oligomer.
[0020] Patent Document 5 discloses a method for producing a prepreg
comprising slurrying polyarylene sulfide in a dispersion medium to
facilitate the impregnation into a glass fiber mat. Patent Document
6 discloses a method for producing a laminate not through a
prepreg, the method comprising laminating relatively
low-molecular-weight polyarylene sulfide in the form of a sheet
together with fiber substrates.
[0021] Patent Document 7 discloses a prepreg obtained by
impregnating reinforcing fibers with low-molecular-weight cyclic
polyarylene sulfide. This method produces a prepreg with high
productivity because the cyclic polyarylene sulfide has excellent
impregnation properties. This method also provides a laminate
having excellent mechanical properties by thermally polymerizing
the cyclic polyarylene sulfide during molding.
[0022] Patent Document 8 proposes a method comprising placing
crystalline thermoplastic resin films on both surfaces of a
sheet-like substrate made of continuous reinforcing fibers,
applying a pressure of 5 to 30 kg/cm.sup.2 (about 0.5 to 3 MPa) at
a temperature 150.degree. C. higher than the melting point of the
resin, and impregnating the thermoplastic resin into the
reinforcing fiber bundle.
[0023] Patent Document 9 discloses a method for producing a
fiber-reinforced molding substrate comprising combining a
continuous reinforcing fiber bundle with low-molecular-weight
cyclic polyarylene sulfide, and heating the composite at 200 to
450.degree. C. to polymerize the cyclic polyarylene sulfide into
high-molecular-weight polyarylene sulfide.
[0024] Patent Document 10 discloses a method for producing a
fiber-reinforced composite material comprising preliminarily
forming polyarylene sulfide having a melt viscosity of 300 to 2,000
Pas and a tensile elongation at break of 10% or more into a sheet,
laminating the sheet and reinforcing fiber substrates alternately,
and compressing the laminate at a pressure of 0.98 to 9.8 MPa at a
temperature of 300 to 350.degree. C. to impregnate the polyarylene
sulfide into the reinforcing fiber substrate.
[0025] Patent Document 11 discloses a method for producing a
fiber-reinforced composite material comprising heat-melting a
polyarylene sulfide prepolymer at 200 to 300.degree. C. to form a
melt solution having a melt viscosity of 10 Pas or lower,
impregnating the melt solution into a reinforcing fiber substrate,
and then heating the resultant at 300 to 400.degree. C. to
polymerize the polyarylene sulfide prepolymer. This is an excellent
production method that is able to produce a fiber-reinforced
composite material comprising a reinforcing fiber substrate and
high-molecular-weight polyarylene sulfide easily with high
productivity.
[0026] Patent Document 1: JP H 10-138379 A
[0027] Patent Document 2: JP 2008-231291 A
[0028] Patent Document 3: JP 2008-231292 A
[0029] Patent Document 4: JP H 03-88828 A
[0030] Patent Document 5: JP H 05-39371 A
[0031] Patent Document 6: JP H 09-25346 A
[0032] Patent Document 7: JP 2008-231237 A
[0033] Patent Document 8: JP H 08-118489 A
[0034] Patent Document 9: JP 2008-231289 A
[0035] Patent Document 10: Japanese Patent No. 3598510
[0036] Patent Document 11: JP 2008-231236 A
SUMMARY OF THE INVENTION
[0037] The method disclosed in Patent Document 1 satisfies
impregnation properties when a low-molecular-weight thermoplastic
resin is used, but, on the other hand, presents problems of poor
handleability of a molding material and difficulty in sufficiently
enhancing the properties of a molded article.
[0038] The molding material disclosed in Patent Document 2 has
excellent heat resistance because polyarylene sulfide prepolymer is
used. However, in situations where various thermoplastic resins are
selected for a matrix resin according to diversified needs for a
fiber-reinforced composite material, in addition to the polyarylene
sulfide prepolymer, highly heat-resistant impregnation/dispersion
aids have been demanded from the standpoint of compatibility with
the matrix resin.
[0039] The molding material disclosed in Patent Document 3 has
excellent heat resistance and dynamic properties because
high-molecular-weight polyarylene sulfide is used. However, in
situations where various thermoplastic resins are selected for a
matrix resin according to diversified needs for a fiber-reinforced
composite material, in addition to polyarylene sulfide, molding
materials comprising a highly heat-resistant thermoplastic resin
have been demanded from the standpoint of compatibility with the
matrix resin.
[0040] The method disclosed in Patent Document 4 has a problem in
that the melting point of the resulting cyclic poly (aryl ether)
oligomer is as high as 340.degree. C. or higher, and a heating
process at a high temperature is necessary for production of a
molding material. Accordingly, molding materials that can be easily
produced at a lower temperature have been demanded from the
standpoint of industrial economic efficiency and productivity.
[0041] The method disclosed in Patent Document 5 has a problem in
that equipment and time are required for drying the dispersion
medium, and besides it is difficult to completely remove the
dispersion medium, so that sufficient mechanical properties cannot
be provided due to voids formed by volatilization of the dispersion
medium during lamination molding. The method disclosed in Patent
Document 6 has a problem in that high-temperature/high-pressure
molding conditions are required, and defects such as
non-impregnation result in poor mechanical properties.
[0042] The prepreg disclosed in Patent Document 7 has excellent
heat resistance because polyarylene sulfide prepolymer is used.
However, as needs for a fiber-reinforced composite material are
diversified, in addition to polyarylene sulfide, molding materials
comprising a highly heat-resistant thermoplastic resin, for
example, poly (phenylene ether ether ketone) have been
demanded.
[0043] In the method disclosed in Patent Document 8, since a harsh
temperature is required for impregnation of a thermoplastic resin,
thermal decomposition of the resin is caused; consequently, the
properties of a molded article cannot be enhanced sufficiently, and
it is difficult to produce a molding material economically with
high productivity.
[0044] The method disclosed in Patent Document 9 is an excellent
production method that is able to produce a molding material
comprising a continuous reinforcing fiber bundle and
high-molecular-weight polyarylene sulfide easily with high
productivity. However, as needs for a fiber-reinforced composite
material comprising a thermoplastic resin are diversified, in
addition to polyarylene sulfide, molding materials comprising a
highly heat-resistant thermoplastic resin, for example, polyether
ether ketone have been demanded.
[0045] Further, the melt viscosity was measured, and the melt
viscosity at 230.degree. C. of the poly (phenylene ether ether
ketone) oligomer (B) was 0.030 Pas.
Reference Example 3
[0046] Here, synthesis in accordance with the common method for
producing a poly (phenylene ether ether ketone) described in
Examples of JP 2007-506833 A will be described.
[0047] The method disclosed in Patent Document 11 has excellent
heat resistance because polyarylene sulfide prepolymer is used.
However, as needs for a fiber-reinforced composite material are
diversified, in addition to polyarylene sulfide, fiber-reinforced
composite materials comprising a highly heat-resistant
thermoplastic resin, for example, poly (phenylene ether ether
ketone) have been demanded.
[0048] The present invention aims to overcome the problems of the
prior art and provide, by using a poly (phenylene ether ether
ketone) oligomer with improved melting properties in a molding
material comprising a continuous reinforcing fiber bundle and a
thermoplastic resin, a molding material that is excellent in
productivity, handleability, and moldability and provides a molded
article having excellent dynamic properties, and a molding method
excellent in productivity and moldability using the molding
material.
[0049] The present invention aims to solve the problems mentioned
above and provide a method for producing a molding material and
fiber-reinforced composite material comprising a reinforcing fiber
substrate and poly (phenylene ether ether ketone) with more ease
and high productivity.
[0050] To solve these problems, the molding material of embodiments
of the present invention has the following constitution.
[0051] A molding material comprising:
a composite of 1 to 50 wt % of a continuous reinforcing fiber
bundle (A) and 0.1 to 20 wt % of a poly (phenylene ether ether
ketone) oligomer (B); and 30 to 98.9 wt % of a thermoplastic resin
(C) adhering to the composite, wherein the component (B) has a
melting point of not higher than 270.degree. C.
[0052] The molding method of embodiments of the present invention
has the following constitution; i.e.,
a molding method, comprising press-molding the molding material
described above using a mold.
[0053] The method for producing a molding material of the present
invention can have the following constitution; i.e.,
A method for producing a molding material, comprising the steps of:
(I) drawing and continuously feeding a reinforcing fiber substrate
(A'); (II) combining the component (A') with a poly (phenylene
ether ether ketone) oligomer (B) to form a composite; (III)
polymerizing the component (B) into a poly (phenylene ether ether
ketone) (B'); and (IV) cooling and taking up the composite of the
component (A') and the component (B'), wherein the component (B)
has a melting point of not higher than 270.degree. C.
[0054] The method for producing a fiber-reinforced composite
material of the present invention may have any one of the
constitutions (1) to (3) below: i.e.,
(1) A method for producing a fiber-reinforced composite material,
comprising the steps of: (I-1) placing a reinforcing fiber
substrate (A') in a mold; (II-1) heat-melting a poly (phenylene
ether ether ketone) oligomer (B) to form a melt solution; (III-1)
injecting the melt solution obtained in the step (II-1) into the
mold of the step (I-1) to impregnate the component (B) into the
component (A'); and (IV-1) thermally polymerizing the component (B)
into a poly (phenylene ether ether ketone) (B'), wherein the
component (B) used in the step (II-1) has a melting point of not
higher than 270.degree. C., or (2) A method for producing a
fiber-reinforced composite material, comprising the steps of: (I-2)
drawing and continuously feeding a reinforcing fiber substrate
(A'); (II-2) heat-melting a poly (phenylene ether ether ketone)
oligomer (B) in an impregnation bath to form a melt solution;
(III-2) passing the component (A') continuously through the
impregnation bath of the step (II-2) to impregnate the component
(B) into the component (A') and winding the resulting composite
around a mandrel; and (IV-2) thermally polymerizing the component
(B) into a poly (phenylene ether ether ketone) (B'), wherein the
component (B) used in the step (II-2) has a melting point of not
higher than 270.degree. C., or (3) A method for producing a
fiber-reinforced composite material, comprising the steps of: (I-3)
drawing and continuously feeding a reinforcing fiber substrate
(A'); (II-3) heat-melting a poly (phenylene ether ether ketone)
oligomer (B) in an impregnation bath to form a melt solution;
(III-3) passing the component (A') continuously through the
impregnation bath of the step (II-3) to form a composite of the
component (B) and the component (A') impregnated therewith; and
(IV-3) pultruding the composite obtained continuously through a
mold to thermally polymerize the component (B) into a poly
(phenylene ether ether ketone) (B'), wherein the component (B) used
in the step (II-3) has a melting point of not higher than
270.degree. C.
[0055] In the molding material of the present invention, the
component (B) preferably comprises a cyclic poly (phenylene ether
ether ketone) in an amount of 60 wt % or more.
[0056] In the molding material of the present invention, the
component (B) is preferably a mixture of cyclic poly (phenylene
ether ether ketone)s having different numbers of repeating units
(m).
[0057] In the molding material of the present invention, the
composite preferably further comprises 0.001 to 20 mol % of a
polymerization catalyst (D) per 1 mol of ether ether ketone
structural unit in the component (B).
[0058] The molding material of the present invention is preferably
a molding material comprising a composite of 1 to 50 wt % of a
continuous reinforcing fiber bundle (A) and 0.1 to 30 wt % of a
poly (phenylene ether ether ketone) (B'), and 20 to 98.9 wt % of a
thermoplastic resin (C) adhering to the composite, wherein the
component (B') is a poly (phenylene ether ether ketone) obtained by
polymerizing a poly (phenylene ether ether ketone) oligomer (B)
having a melting point of not higher than 270.degree. C. using a
polymerization catalyst (D).
[0059] In the molding material of the present invention, the
component (B') preferably has a crystal melting enthalpy .DELTA.H
determined by DSC of not less than 40 J/g.
[0060] In the molding material of the present invention, the
component (A) preferably contains at least 10,000 carbon fiber
monofilaments.
[0061] In the molding material of the present invention, the
component (C) is preferably at least one selected from polyamide
resin, polyetherimide resin, polyamide-imide resin, polyether ether
ketone resin, and polyphenylene sulfide resin.
[0062] In the molding material of the present invention, the
component (D) is preferably an alkali metal salt.
[0063] In the molding material of the present invention, it is
preferred that the component (A) be arranged substantially parallel
to the direction of the shaft center, and the length of the
component (A) be substantially the same as the length of the
molding material.
[0064] In the molding material of the present invention, it is
preferred that the composite forms a core structure, and the
component (C) surround the composite to form a core-sheath
structure.
[0065] In the molding material of the present invention, the form
of the molding material is preferably a long-fiber pellet.
[0066] The molding material of the present invention is preferably
a molding material comprising a reinforcing fiber substrate (A'), a
poly (phenylene ether ether ketone) oligomer (B), and a
polymerization catalyst (D), wherein the component (B) has a
melting point of not higher than 270.degree. C.
[0067] In the molding material of the present invention, the
component (B) preferably comprises a cyclic poly (phenylene ether
ether ketone) in an amount of 60 wt % or more.
[0068] In the molding material of the present invention, the
component (B) is preferably a mixture of cyclic poly (phenylene
ether ether ketone)s having different numbers of repeating units
(m).
[0069] In the molding material of the present invention, the
component (A') is preferably a carbon fiber.
[0070] In the molding material of the present invention, the
content of the component (A') is preferably 30 wt % or more.
[0071] In the molding material of the present invention, the
content of the component (D) is preferably 0.001 to 20 mol % per 1
mol of ether ether ketone structural unit in the component (B).
[0072] In the molding method of the present invention, the
component (B) is preferably polymerized into a poly (phenylene
ether ether ketone) (B') in the mold.
[0073] In the molding method of the present invention, the surface
temperature of the mold during polymerization of the component (B)
into the component (B') is preferably not higher than the melting
point of the component (B').
[0074] In the molding method of the present invention, after the
component (B) is polymerized into the component (B') in the mold,
the mold is preferably opened without cooling to take out a molded
article.
[0075] In the method for producing a molding material of the
present invention, the component (B) preferably comprises a cyclic
poly (phenylene ether ether ketone) in an amount of 60 wt % or
more.
[0076] In the method for producing a molding material of the
present invention, the component (B) is preferably a mixture of
cyclic poly (phenylene ether ether ketone)s having different
numbers of repeating units (m).
[0077] In the method for producing a molding material of the
present invention, it is preferable to further combining a
polymerization catalyst (D) with the other components in the step
(II).
[0078] In the method for producing a molding material of the
present invention, the steps (I) to (IV) are preferably performed
on-line.
[0079] In the method for producing a molding material of the
present invention, the take-up speed in the step (IV) is preferably
1 to 100 m/min.
[0080] In the method for producing a molding material of the
present invention, it is preferred that in the step (II), the
heat-melted component (B) be applied to the component (A') to form
a composite.
[0081] In the method for producing a molding material of the
present invention, it is preferred that in the step (II), the
component (B) in at least one form selected from the group
consisting of particles, fibers, and flakes be applied to the
component (A') to form a composite.
[0082] In the method for producing a molding material of the
present invention, it is preferred that in the step (II), the
component (B) in at least one form selected from the group
consisting of a film, a sheet, and a nonwoven fabric be applied to
the component (A') to form a composite.
[0083] In the method for producing a fiber-reinforced composite
material of the present invention, the component (B) preferably
comprises a cyclic poly (phenylene ether ether ketone) in an amount
of 60 wt % or more.
[0084] In the method for producing a fiber-reinforced composite
material of the present invention, the component (B) is preferably
a mixture of cyclic poly (phenylene ether ether ketone)s having
different numbers of repeating units (m).
[0085] In the method for producing a fiber-reinforced composite
material of the present invention, it is preferable to further add
a polymerization catalyst (D) to a melt solution of the component
(B).
[0086] In the method for producing a fiber-reinforced composite
material of the present invention, in the step (II-1), (II-2), or
(II-3), the melt viscosity of the melt solution of the component
(B) is preferably adjusted to 10 Pas or lower.
[0087] In the method for producing a fiber-reinforced composite
material of the present invention, in the step (IV-1), (IV-2), or
(IV-3), the thermal polymerization is preferably performed at a
temperature of 160.degree. C. to 330.degree. C.
[0088] By using the molding material comprising a poly (phenylene
ether ether ketone) oligomer (B) or poly (phenylene ether ether
ketone) (B') according to the present invention, a molded article
having excellent dynamic properties can be easily produced through
the use of the molding material excellent in economic efficiency
and productivity.
[0089] The molding material comprising a reinforcing fiber
substrate (A') according to the present invention is excellent in
handleability and moldability and also can achieve high fiber
content, thereby providing a molded article having excellent
mechanical properties. Further, the molding material is excellent
in economic efficiency, productivity, and handleability because it
can be molded into a fiber-reinforced composite material by heating
the molding material at a low temperature for a short time.
[0090] According to the method for producing a molding material of
the present invention, a reinforcing fiber substrate can be easily
combined with a poly (phenylene ether ether ketone), which enables
improved productivity such as increased take-up speed and improved
economic efficiency such as lowered process temperature. Thus the
method is suitably used for producing a molding material such as a
prepreg, semipreg, and fabric.
[0091] According to the method for producing a fiber-reinforced
composite material of the present invention, a reinforcing fiber
substrate can be easily combined with a poly (phenylene ether ether
ketone), which enables improved productivity due to improved
impregnation properties and improved economic efficiency such as
lowered process temperature. Thus the method is suitably used for
producing a fiber-reinforced composite material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0092] FIG. 1 is a schematic view showing an example of a
configuration of a composite of a reinforcing fiber bundle (A) and
a poly (phenylene ether ether ketone) oligomer (B) or poly
(phenylene ether ether ketone) (B');
[0093] FIG. 2 is a schematic view showing an example of a preferred
aspect of the molding material of the present invention;
[0094] FIG. 3 is a schematic view showing an example of a
configuration of a cross-section in the direction of the shaft
center according to a preferred aspect of the molding material of
the present invention;
[0095] FIG. 4 is a schematic view showing an example of a
configuration of a cross-section in the direction of the shaft
center according to a preferred aspect of the molding material of
the present invention;
[0096] FIG. 5 is a schematic view showing an example of a
configuration of a cross-section in the direction of the shaft
center according to a preferred aspect of the molding material of
the present invention;
[0097] FIG. 6 is a schematic view showing an example of a
configuration of a cross-section in the direction of the shaft
center according to a preferred aspect of the molding material of
the present invention;
[0098] FIG. 7 is a schematic view showing an example of a
configuration of a cross-section in the orthogonal direction
according to a preferred aspect of the molding material of the
present invention;
[0099] FIG. 8 is a schematic view showing an example of a
configuration of a cross-section in the orthogonal direction
according to a preferred aspect of the molding material of the
present invention;
[0100] FIG. 9 is a schematic view showing an example of a
configuration of a cross-section in the orthogonal direction
according to a preferred aspect of the molding material of the
present invention;
[0101] FIG. 10 is a schematic view showing an example of a
configuration of a cross-section in the orthogonal direction
according to a preferred aspect of the molding material of the
present invention;
[0102] FIG. 11 is a schematic view showing an example of a
configuration of a cross-section in the orthogonal direction
according to a preferred aspect of the molding material of the
present invention;
[0103] FIG. 12 is a perspective view of a fixture for evaluating
drape property;
[0104] FIG. 13 is an example of a production apparatus used in the
method for producing a molding material according to the present
invention. The arrow represents the take-up direction of a
fiber-reinforced molding substrate;
[0105] FIG. 14 is an example of a production apparatus used in the
method for producing a molding material according to the present
invention. The arrow represents the take-up direction of a
fiber-reinforced molding substrate;
[0106] FIG. 15 is an example of a production apparatus used in the
method for producing a molding material according to the present
invention. The arrow represents the take-up direction of a
fiber-reinforced molding substrate;
[0107] FIG. 16 is a schematic cross-sectional view showing an
example of a propeller shaft obtained by the present invention;
and
[0108] FIG. 17 is a schematic cross-sectional view showing an
example of a configuration of a cylindrical body made of a
fiber-reinforced composite material obtained by the present
invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0109] The molding material of the present invention preferably
comprises a continuous reinforcing fiber bundle (A) or reinforcing
fiber substrate (A'), a poly (phenylene ether ether ketone)
oligomer (B), and a thermoplastic resin (C). Further, the molding
material of the present invention may further comprise a
polymerization catalyst (D) in a composite, and the poly (phenylene
ether ether ketone) oligomer (B) can be converted into a poly
(phenylene ether ether ketone) (B') by thermal polymerization in
the presence of the polymerization catalyst (D). First, each
component will be described.
<Reinforcing Fiber>
[0110] Examples of reinforcing fibers that can be used for the
continuous reinforcing fiber bundle (A) or reinforcing fiber
substrate (A') of the present invention include, but are not
limited to, carbon fibers, glass fibers, aramid fibers, boron
fibers, alumina fibers, mineral fibers, and silicon carbide fibers,
and two or more of such fibers can be used in combination.
[0111] In particular, carbon fibers are preferred because they have
excellent specific strength and specific rigidity and improve the
dynamic properties of a molded article. Among them, to obtain a
molded article having a light weight, high strength, and high
elastic modulus, carbon fibers are preferably used, and, in
particular, carbon fibers with a tensile modulus of 200 to 700 GPa
are preferably used. Further, carbon fibers and metal-coated
reinforcing fibers have an effect of improving the conductivity of
a molded article because of having high conductivity, and thus are
particularly preferred, for example, for a housing of electronic
equipment that requires electromagnetic shielding properties.
[0112] In a more preferred embodiment of carbon fibers, the amount
of surface functional groups (O/C), which is the atomic ratio of
oxygen (O) to carbon (C) on the fiber surface, measured by X-ray
photoelectron spectroscopy is in the range of 0.05 to 0.4. The
higher the O/C, the larger the amount of functional groups on the
carbon fiber surface, and this increases adhesion to a matrix
resin. However, if the O/C is too high, the crystal structure on
the carbon fiber surface may be destroyed. When the O/C is within
the preferred range, a molded article having excellently balanced
dynamic properties can be obtained.
[0113] The amount of surface functional groups (O/C) is determined
by X-ray photoelectron spectroscopy according to the following
procedure. First, carbon fibers from which a sizing agent and the
like have been removed with a solvent are cut and spread on a
sample support made of copper. Thereafter, the photoelectron
take-off angle is set at 90.degree., and using MgK.sub..alpha.1, 2
as an X-ray source, the inside of a sample chamber is kept at
1.times.10.sup.-8 Torr. As a correction of a peak associated with
electrification during the measurement, the kinetic energy value
(K.E.) of the main peak of C 1s is set at 969 eV. The C 1s peak
area is determined by drawing a straight baseline in the K.E. range
of 958 to 972 eV. The O 1s peak area is determined by drawing a
straight baseline in the K.E. range of 714 to 726 eV. The amount of
surface functional groups (O/C) is calculated as an atomic ratio
from the ratio of the O 1S peak area to the C 1S peak area
described above using an apparatus-specific sensitivity correction
value.
[0114] The continuous reinforcing fiber bundle (A) used for the
molding material of the present invention means that a reinforcing
fiber bundle comprising unidirectionally arranged monofilaments is
continuous in the longitudinal direction. However, all the
monofilaments in the reinforcing fiber bundle need not necessarily
be continuous throughout the whole length, and some of the
monofilaments may be broken halfway. Examples of such continuous
reinforcing fiber bundles include a unidirectional fiber bundle, a
bidirectional fiber bundle, and a multidirectional fiber bundle,
and a unidirectional fiber bundle can be more preferably used from
the standpoint of productivity during the process for producing a
molding material.
[0115] The reinforcing fiber bundle (A) in the present invention
becomes more economically advantageous as the number of reinforcing
fiber monofilaments increases, and thus the number of monofilaments
is preferably 10,000 or more. However, the larger number of
reinforcing fiber monofilaments tends to be disadvantageous to
impregnation properties of a matrix resin, and, therefore, when a
carbon fiber bundle is used as the reinforcing fiber bundle (A),
the number of monofilaments is more preferably 15,000 to 100,000,
and particularly preferably 20,000 to 50,000, in order to achieve
the balance between economic efficiency and impregnation
properties. In particular, excellent impregnation properties of
thermoplastic resin during the process for producing a molding
material and satisfactory dispersion of reinforcing fibers into a
molded article at the time of injection molding, which are the
effects of the present invention, are suitable for a reinforcing
fiber bundle having a larger number of fibers.
[0116] Further, to bundle monofilaments into a reinforcing fiber
bundle, a sizing agent may be used in addition to the poly
(phenylene ether ether ketone) oligomer (B) of the present
invention. This is for the purpose of improving handleability
during transfer of reinforcing fibers and processability during the
process for producing a molding material by applying the sizing
agent to the reinforcing fiber bundle. Sizing agents such as epoxy
resin, urethane resin, acrylic resin, and various thermoplastic
resins can be used alone or in combination of two or more thereof
as long as the object of the present invention is achieved.
[0117] Examples of the form and arrangement of the reinforcing
fiber substrate (A') used in the present invention include, but are
not limited to, substrates comprising unidirectionally arranged
continuous reinforcing fibers (hereinafter also referred to simply
as "unidirectionally arranged substrate"), fabrics (cloths),
nonwoven fabrics, mats, knits, braids, yarns, and tows. Among them,
unidirectionally arranged substrates are preferably used because
strength properties can be easily designed depending on the
lamination structure; fabrics are preferred because they can be
easily shaped into a curved shape; and nonwoven fabrics and mats
are preferably used because they can be easily molded in the
thickness direction. "Unidirectionally arranged substrate" as used
herein refers to a substrate comprising a plurality of reinforcing
fibers arranged in parallel. Such a unidirectionally arranged
substrate can be obtained, for example, by the method in which a
plurality of the reinforcing fiber bundles (A) mentioned above is
unidirectionally aligned and formed into a sheet.
[0118] When the reinforcing fiber substrate (A') is a
unidirectionally arranged substrate, a fabric, a nonwoven fabric,
or a mat, the number of reinforcing fiber monofilaments is not
particularly restricted.
[0119] Further, to the reinforcing fiber substrate (A'), a binder
may be added in addition to the component (B) in the present
invention in order to prevent separation of monofilaments. This is
for the purpose of improving handleability during transfer of the
reinforcing fiber substrate (A') and processability during the
process for producing a molding material by applying the binder to
the reinforcing fiber substrate (A'). Binders such as epoxy resin,
urethane resin, acrylic resin, and various thermoplastic resins can
be used alone or in combination of two or more thereof as long as
the object of the present invention is achieved.
<Poly (Phenylene Ether Ether Ketone) Oligomer (B)>
[0120] The poly (phenylene ether ether ketone) oligomer (B) used in
the present invention preferably has a melting point of not higher
than 270.degree. C., preferably not higher than 250.degree. C.,
more preferably not higher than 230.degree. C., still more
preferably not higher than 200.degree. C., and particularly
preferably not higher than 180.degree. C., for example. The lower
the melting point of the poly (phenylene ether ether ketone)
oligomer (B) is, the lower the processing temperature can be, and
the lower the process temperature can be set. This is advantageous
because the energy required for processing can be reduced. Further,
the lower the melting point of the poly (phenylene ether ether
ketone) oligomer (B) is, the lower the molding temperature can be;
consequently, the energy required for a molding process can be
reduced, and thermal degradation of components can be reduced.
Further, since the process temperature can be set low, for example,
the melt-kneading temperature can be set sufficiently lower than
the polymerization temperature in the step of melting and mixing
the polymerization catalyst (D) mentioned below and the poly
(phenylene ether ether ketone) oligomer (B). These effects inhibit
such an unfavorable reaction that in the process for producing a
molding material, the polymerization of the poly (phenylene ether
ether ketone) oligomer (B) proceeds during storage or before
impregnation into the reinforcing fiber bundle (A) or reinforcing
fiber substrate (A'), resulting in increased melt viscosity. The
melting point of the poly (phenylene ether ether ketone) oligomer
(B) can be measured by observing an endothermic peak temperature
using a differential scanning calorimeter.
[0121] The poly (phenylene ether ether ketone) oligomer (B) in the
present invention is preferably a poly (phenylene ether ether
ketone) composition comprising a cyclic poly (phenylene ether ether
ketone) in an amount of 60 wt % or more, more preferably 65 wt % or
more, still more preferably 70 wt % or more, and yet more
preferably 75 wt % or more.
[0122] The cyclic poly (phenylene ether ether ketone) in the
present invention is a cyclic compound having p-phenylene ketone
and p-phenylene ether in a repeating structural unit, represented
by Formula (a) below.
##STR00001##
[0123] In Formula (a), the number of repeating units (m) is in the
range of 2 to 40, more preferably 2 to 20, still more preferably 2
to 15, and particularly preferably 2 to 10, for example. The
melting point of the poly (phenylene ether ether ketone) oligomer
(B) tends to increase with increasing number of repeating units
(m), and, therefore, the number of repeating units (m) is
preferably in the above range in order to melt the poly (phenylene
ether ether ketone) oligomer (B) at a low temperature.
[0124] Further, the poly (phenylene ether ether ketone) oligomer
(B) is preferably a mixture of cyclic poly (phenylene ether ether
ketone)s having different numbers of repeating units (m), more
preferably at least three different numbers of repeating units (m),
still more preferably at least four numbers of repeating units (m),
and particularly preferably at least five numbers of repeating
units (m). Furthermore, it is particularly preferred that the
number of repeating units (m) be consecutive. As compared to a
single compound having a single number of repeating units (m), a
mixture of cyclic poly (phenylene ether ether ketone)s having
different numbers of repeating units (m) tends to have a low
melting point. Further, as compared to a cyclic poly (phenylene
ether ether ketone) mixture of cyclic poly (phenylene ether ether
ketone)s having two different numbers of repeating units (m), a
mixture of cyclic poly (phenylene ether ether ketone)s having three
or more numbers of repeating units (m) tends to have an even lower
melting point. Furthermore, as compared to a mixture of cyclic poly
(phenylene ether ether ketone)s having nonconsecutive numbers of
repeating units (in), a mixture of cyclic poly (phenylene ether
ether ketone)s having consecutive numbers of repeating units (m)
tends to have an even lower melting point. The cyclic poly
(phenylene ether ether ketone)s having different numbers of
repeating units (in) can be analyzed by fractionation by
high-performance liquid chromatography. Further, composition of the
poly (phenylene ether ether ketone) oligomer (B), i.e., the weight
fraction of each cyclic poly (phenylene ether ether ketone) having
different numbers of repeating units (m) contained in the poly
(phenylene ether ether ketone) oligomer (B) can be calculated from
the peak area ratio of each cyclic poly (phenylene ether ether
ketone) by high-performance liquid chromatography.
[0125] The main example of impurity components in the poly
(phenylene ether ether ketone) oligomer (B), i.e., components other
than the cyclic poly (phenylene ether ether ketone) is a linear
poly (phenylene ether ether ketone). Since the linear poly
(phenylene ether ether ketone) has a high melting point, the
melting point of the poly (phenylene ether ether ketone) oligomer
(B) tends to increase as the weight fraction of the linear poly
(phenylene ether ether ketone) increases. Therefore, when the
weight fraction of the cyclic poly (phenylene ether ether ketone)s
in the poly (phenylene ether ether ketone) oligomer (B) is within
the range described above, the poly (phenylene ether ether ketone)
oligomer (B) tends to have a low melting point.
[0126] The poly (phenylene ether ether ketone) oligomer (B) in the
present invention having characteristics described above preferably
has a reduced viscosity (.eta.) of 0.1 dL/g or less, for example,
more preferably 0.09 dL/g or less, and still more preferably 0.08
dL/g or less, for example. "Reduced viscosity" as used herein,
unless otherwise specified, refers to the value obtained by
measuring a solution of concentrated sulfuric acid with a
concentration of 0.1 g/dL (the weight of the poly (phenylene ether
ether ketone) oligomer (B)/the volume of 98 wt % concentrated
sulfuric acid) at 25.degree. C. using an Ostwald viscosimeter
immediately after completion of dissolution in order to minimize
the influence of sulfonation. The reduced viscosity was calculated
by the following equation.
.eta.={(t/t.sub.0)-1}/C
(wherein t represents the transit time of a sample solution in
seconds; to represents the transit time of a solvent (98 wt %
concentrated sulfuric acid) in seconds; and C represents the
concentration of a solution.)
[0127] Examples of methods for obtaining the poly (phenylene ether
ether ketone) oligomer (B) used in the present invention include
the methods [B1] to [B3] below. [B1] The production method in which
a mixture containing at least a dihalogenated aromatic ketone
compound, dihydroxy aromatic compound, base, and organic polar
solvent is heated and allowed to react;
[0128] [B2] The production method in which a mixture containing at
least a linear poly (phenylene ether ether ketone), dihalogenated
aromatic ketone compound, dihydroxy aromatic compound, base, and
organic polar solvent is heated and allowed to react; or [B3] The
production method in which a mixture containing at least a linear
poly (phenylene ether ether ketone), basic compound, and organic
polar solvent is heated and allowed to react is strongly desired to
be used.
[0129] Representative reaction formulas of the above-mentioned
methods [B1] to [B3] for producing a poly (phenylene ether ether
ketone) oligomer (B) are shown below.
##STR00002##
<Polymerization Catalyst (D)>
[0130] In the present invention, the polymerization catalyst (D) is
not particularly restricted as long as it is a compound having an
effect of accelerating thermal polymerization of a poly (phenylene
ether ether ketone) oligomer (B) into a poly (phenylene ether ether
ketone) (B'). Known catalysts such as photopolymerization
initiators, radical polymerization initiators, cationic
polymerization initiators, anionic polymerization initiators, and
transition metal catalysts can be used, and, in particular, anionic
polymerization initiators are preferred. Examples of anionic
polymerization initiators include alkali metal salts such as
inorganic alkali metal salts and organic alkali metal salts.
Examples of inorganic alkali metal salts include alkali metal
halides such as sodium fluoride, potassium fluoride, cesium
fluoride, and lithium chloride. Examples of organic alkali metal
salts include alkali metal alkoxides such as sodium methoxide,
potassium methoxide, sodium ethoxide, potassium ethoxide, sodium
tert-butoxide, and potassium tert-butoxide; alkali metal phenoxides
such as sodium phenoxide, potassium phenoxide,
sodium-4-phenoxyphenoxide, and potassium-4-phenoxyphenoxide; and
alkali metal acetates such as lithium acetate, sodium acetate, and
potassium acetate. It is presumed that these anionic polymerization
initiators exhibit catalytic action by nucleophilically attacking
the poly (phenylene ether ether ketone) oligomer (B). Therefore,
compounds having a nucleophilic attack capability comparable to
that of these anionic polymerization initiators can also be used as
the catalyst, and examples of such compounds having a nucleophilic
attack capability include polymers having an anionically
polymerizable terminal. These anionic polymerization initiators may
be used alone or in combination of two or more thereof. When
thermal polymerization of the poly (phenylene ether ether ketone)
oligomer (B) is carried out in the presence of such a preferred
catalyst(s), a poly (phenylene ether ether ketone) (B') is likely
to be obtained in a short time, and, specifically, the heating time
in the thermal polymerization is not longer than 2 hours, not
longer than 1 hour, and not longer 0.5 hour, for example.
[0131] The amount of catalyst used varies depending on the
molecular weight of the poly (phenylene ether ether ketone) (B') of
interest and the type of catalyst, but it is generally 0.001 to 20
mol %, preferably 0.005 to 15 mol %, and more preferably 0.01 to 10
mol %, based on 1 mol of the repeating unit represented by the
following formula, which is a main structural unit of the poly
(phenylene ether ether ketone) (B'). When the catalyst(s) is/are
added in an amount in this preferred range, the thermal
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) is likely to proceed in a short time.
##STR00003##
[0132] Examples of the method of adding a polymerization catalyst
(D) include, but are not limited to, the method in which a mixture
of a poly (phenylene ether ether ketone) oligomer (B) and a
polymerization catalyst (D) is preliminarily prepared, and the
mixture is combined with reinforcing fibers.
[0133] The mixture of a poly (phenylene ether ether ketone)
oligomer (B) and a polymerization catalyst (D) may be obtained by
any method, but it is preferable to add the polymerization catalyst
(D) to the poly (phenylene ether ether ketone) oligomer (B) and
then disperse the polymerization catalyst (D) uniformly. Examples
of the method for uniform dispersion include mechanical dispersion
and dispersion using a solvent. Specific examples of the mechanical
dispersion include methods using a grinder, stirrer, mixer, shaker,
or mortar. Specific examples of the dispersion using a solvent
include a method comprising dissolving or dispersing the poly
(phenylene ether ether ketone) oligomer (B) in an appropriate
solvent; adding the polymerization catalyst (D) thereto; and then
removing the solvent. When the polymerization catalyst (D) is solid
in dispersing the polymerization catalyst (D), the polymerization
catalyst (D) preferably has an average particle size of 1 mm or
smaller to allow more uniform dispersion.
<Poly (Phenylene Ether Ether Ketone) (B')>
[0134] The poly (phenylene ether ether ketone) (B') in the present
invention is preferably obtained by conversion of a poly (phenylene
ether ether ketone) oligomer (B) through thermal polymerization in
the presence of a polymerization catalyst (D). The poly (phenylene
ether ether ketone) (B') as described herein is a linear compound
having p-phenylene ketone and p-phenylene ether in a repeating
structural unit, represented by Formula (b) below.
##STR00004##
[0135] The reduced viscosity (.eta.) of the poly (phenylene ether
ether ketone) (B') in the present invention is not critical, but it
is preferably in the range of 0.1 to 2.5 dL/g, more preferably 0.2
to 2.0 dL/g, and still more preferably 0.3 to 1.8 dL/g, for
example. When the viscosity is controlled to be in such a preferred
range, a molding material that has excellent moldability and
provides a molded article with excellent dynamic properties can be
obtained.
[0136] The melting point of the poly (phenylene ether ether ketone)
(B') in the present invention cannot be uniquely determined because
it varies depending on the composition and molecular weight of the
poly (phenylene ether ether ketone) oligomer (B), the weight
fraction of cyclic poly (phenylene ether ether ketone)s contained
in the poly (phenylene ether ether ketone) oligomer (B), and the
conditions of heating, but it is preferably in the range of 270 to
450.degree. C., more preferably 280 to 400.degree. C., and still
more preferably 300 to 350.degree. C., for example. When the
melting point is controlled to be in such a preferred temperature
range, a molding material having excellent moldability and heat
resistance can be obtained. The melting point of the poly
(phenylene ether ether ketone) (B') can be measured in such a
manner that the part of the poly (phenylene ether ether ketone)
(B') is taken out physically from the molding material of the
present invention, and the endothermic peak temperature of this
sample is observed using a differential scanning calorimeter.
[0137] When the poly (phenylene ether ether ketone) oligomer (B) is
converted into a poly (phenylene ether ether ketone) (B') by
thermal polymerization, the heating temperature is preferably not
lower than the melting point of the poly (phenylene ether ether
ketone) oligomer (B), and such temperature conditions can be used
without any restriction. When the heating temperature is lower than
the melting point of the poly (phenylene ether ether ketone)
oligomer (B), it is likely that it will take a long time to obtain
a poly (phenylene ether ether ketone) (B') by thermal
polymerization or that the thermal polymerization will not proceed,
so that a poly (phenylene ether ether ketone) (B') cannot be
obtained. The lower limit of the heating temperature is, for
example, not lower than 160.degree. C., preferably not lower than
200.degree. C., more preferably not lower than 230.degree. C., and
still more preferably not lower than 270.degree. C. In this
temperature range, it is likely that the poly (phenylene ether
ether ketone) oligomer (B) will melt and a poly (phenylene ether
ether ketone) (B') can be obtained in a short time.
[0138] When the temperature in thermal polymerization is too high,
undesirable side reactions as represented by cross-linking reaction
and decomposition reaction are likely to occur, for example,
between the poly (phenylene ether ether ketone) oligomers (B),
between the poly (phenylene ether ether ketone)s (B') formed by
heating, and between the poly (phenylene ether ether ketone) (B')
and the poly (phenylene ether ether ketone) oligomer (B), and the
resulting poly (phenylene ether ether ketone) (B') may have
degraded properties. Thus, it is desirable to avoid temperatures at
which such undesirable side reactions significantly occur. The
upper limit of the heating temperature is, for example, not higher
than 450.degree. C., preferably not higher than 400.degree. C.,
more preferably not higher than 350.degree. C., and still more
preferably not higher than 300.degree. C. When the heating
temperature is not higher than this temperature range, it is likely
that adverse effects of the undesirable side reactions on the
properties of the resulting poly (phenylene ether ether ketone)
(B') can be prevented. In cases where a known poly (phenylene ether
ether ketone) oligomer is used, because of its high melting point,
when the heating temperature is in the preferred temperature range
described above, it is likely that it will take a long time for
thermal polymerization or that the thermal polymerization will not
proceed, so that a poly (phenylene ether ether ketone) (B') cannot
be obtained; whereas in the case of the poly (phenylene ether ether
ketone) oligomer (B) in the present invention characterized by
having a melting point of not higher than 270.degree. C., thermal
polymerization proceeds efficiently in the preferred temperature
range described above, and a poly (phenylene ether ether ketone)
(B') can be obtained.
[0139] The poly (phenylene ether ether ketone) oligomer (B) in the
present invention can also be thermally polymerized at a
temperature not higher than the melting point of the resulting poly
(phenylene ether ether ketone) (B'). The poly (phenylene ether
ether ketone) (B') obtained under such polymerization conditions,
as compared to known poly (phenylene ether ether ketone)s, tends to
have a high melting enthalpy, which results in increased
crystallinity. This is probably because a phenomenon in which
thermal polymerization of the poly (phenylene ether ether ketone)
oligomer (B) and crystallization of the poly (phenylene ether ether
ketone) (B') obtained by the polymerization proceed simultaneously,
i.e., so-called crystallization polymerization is proceeding. The
lower limit of the melting enthalpy of the poly (phenylene ether
ether ketone) (B') obtained by crystallization polymerization is,
for example, not less than 40 J/g, preferably not less than 45 J/g,
and more preferably not less than 50 J/g. The melting enthalpy of
the poly (phenylene ether ether ketone) (B') can be measured in
such a manner that the part of the poly (phenylene ether ether
ketone) (B') is taken out physically from the molding material of
the present invention, and the endothermic peak area of this sample
is observed using a differential scanning calorimeter
[0140] The heating temperature range where such crystallization
polymerization occurs cannot be uniquely defined because it varies
depending on the conditions such as weight fraction and composition
ratio of cyclic poly (phenylene ether ether ketone)s in the poly
(phenylene ether ether ketone) oligomer (B) used, and thermal
polymerization method, but it is, for example, in the range of 160
to 330.degree. C., preferably 200 to 300.degree. C.
[0141] The reaction time cannot be uniquely defined because it
varies depending on the conditions such as weight fraction and
composition ratio of cyclic poly (phenylene ether ether ketone)s in
the poly (phenylene ether ether ketone) oligomer (B) used, heating
temperature, and thermal polymerization method, but it is
preferably set such that the above-described undesirable side
reactions such as cross-linking reaction will not occur, for
example, in the range of 0.001 to 100 hours, preferably 0.005 to 20
hours, and more preferably 0.005 to 10 hours. When the reaction
time is such a preferred reaction time, it is likely that adverse
effects of the progress of undesirable side reactions such as
cross-linking reaction on the properties of the resulting poly
(phenylene ether ether ketone) can be prevented.
<Thermoplastic Resin (C)>
[0142] The thermoplastic resin (C) used in the present invention
may be, but are not limited to, polyester resins such as
polyethylene terephthalate (PET) resin, polybutylene terephthalate
(PBT) resin, polytrimethylene terephthalate (PTT) resin,
polyethylene naphthalate (PENp) resin, and liquid crystal
polyester; polyolefin resins such as polyethylene (PE) resin,
polypropylene (PP) resin, and polybutylene resin; styrene resins;
urethane resins; further, polyoxymethylene (POM) resin, polyamide
(PA) resin, polycarbonate (PC) resin, polymethyl methacrylate
(PMMA) resin, polyvinyl chloride (PVC) resin, polyphenylene sulfide
(PPS) resin, polyphenylene ether (PPE) resin, modified PPE resin,
polyimide (PI) resin, polyamide-imide (PAI) resin, polyetherimide
(PEI) resin, polysulfone (PSU) resin, modified PSU resin,
polyethersulfone (PES) resin, polyketone (PK) resin, polyether
ketone (PEK) resin, polyether ether ketone (PEEK) resin, polyether
ketone ketone (PEKK) resin, polyarylate (PAR) resin, polyether
nitrile (PEN) resin, phenol resin, phenoxy resin, fluorine resins
such as polytetrafluoroethylene; and copolymers, modifications, and
resin blends of two or more thereof.
[0143] Among them, engineering plastics or super engineering
plastics such as polyamide resin, polyetherimide resin,
polyamide-imide resin, polyether ether ketone resin, and
polyphenylene sulfide resin are preferably used, and polyether
ether ketone resin is particularly preferably used because it shows
excellent compatibility with a poly (phenylene ether ether ketone)
oligomer (B), has good fiber dispersibility, and provides a molded
article having excellent appearance.
[0144] Through the use of such a thermoplastic resin (C), the
effect of improving the dynamic properties of a molded article in
the present invention can be better brought out.
[0145] From the standpoint of dynamic properties of a molded
article obtained by molding a molding material, the molecular
weight of the thermoplastic resin (C) used in the present invention
is preferably 10,000 or more, more preferably 20,000 or more, and
particularly preferably 30,000 or more, in terms of weight average
molecular weight. A larger weight average molecular weight is
advantageous because it enhances the strength and ductility of a
matrix resin. The upper limit of the weight average molecular
weight is not particularly limited, but from the standpoint of
fluidity during molding, it is preferably not more than 1,000,000,
and more preferably not more than 500,000, for example. The weight
average molecular weight can be determined using common GPC
(gel-permeation chromatography) such as SEC (size-exclusion
chromatography).
[0146] The thermoplastic resin (C) exemplified above may contain
fiber-reinforcing agents, impact-resistance improvers such as
elastomers or rubber components, and other fillers and additives as
long as the object of the present invention is achieved. Examples
thereof include inorganic fillers, flame retardants,
conductivity-imparting agents, crystal nucleating agents, UV
absorbers, antioxidants, vibration dampers, antimicrobial agents,
insect repellents, deodorizers, stain inhibitors, heat stabilizers,
mold releasing agents, antistatic agents, plasticizers, lubricants,
coloring agents, pigments, dyes, foaming agents, foam suppressors,
and coupling agents.
<Molding Material>
[0147] In a first preferred embodiment, the molding material of the
present invention comprises a reinforcing fiber bundle (A), a poly
(phenylene ether ether ketone) oligomer (B), and a thermoplastic
resin (C).
[0148] Among the components, the amount of the reinforcing fiber
bundle (A) is 1 to 50 wt %, preferably 5 to 45 wt %, and more
preferably 10 to 40 wt %, based on 100 wt % of the total components
(A), (B), and (C). When the amount of the reinforcing fiber bundle
(A) is less than 1 wt %, the resulting molded article may have poor
dynamic properties, and when it is more than 50 wt %, fluidity may
decrease during injection molding.
[0149] The amount of the poly (phenylene ether ether ketone)
oligomer (B) is 0.1 to 20 wt %, preferably 1 to 18 wt %, and more
preferably 5 to 15 wt %, based on 100 wt % of the total components
(A), (B), and (C). When the poly (phenylene ether ether ketone)
oligomer (B) is used in this range, a molding material having
excellent moldability and handleability can be obtained.
[0150] The amount of the thermoplastic resin (C) is 30 to 98.9 wt
%, preferably 37 to 94 wt %, and more preferably 45 to 85 wt %,
based on 100 wt % of the total components (A), (B), and (C). When
the thermoplastic resin (C) is used in this range, a molding
material having excellent moldability and handleability can be
obtained.
[0151] In a second preferred embodiment, the molding material of
the present invention comprises a reinforcing fiber bundle (A), a
poly (phenylene ether ether ketone) (B'), a thermoplastic resin
(C), and a polymerization catalyst (D).
[0152] Among the components, the amount of the reinforcing fiber
bundle (A) is 1 to 50 wt %, preferably 5 to 45 wt %, and more
preferably 10 to 40 wt %, based on 100 wt % of the total components
(A), (B'), and (C). When the amount of the reinforcing fiber bundle
(A) is less than 1 wt %, the resulting molded article may have poor
dynamic properties, and when it is more than 50 wt %, fluidity may
decrease during injection molding.
[0153] The amount of the poly (phenylene ether ether ketone) (B')
is 0.1 to 30 wt %, preferably 1 to 18 wt %, and more preferably 5
to 15 wt %, based on 100 wt % of the total components (A), (B'),
and (C). When the poly (phenylene ether ether ketone) (B') is used
in this range, a molding material having excellent moldability and
handleability can be obtained.
[0154] The amount of the thermoplastic resin (C) is 20 to 98.9 wt
%, preferably 37 to 94 wt %, and more preferably 45 to 85 wt %,
based on 100 wt % of the total components (A), (B'), and (C). When
the thermoplastic resin (C) is used in this range, a molding
material having excellent moldability and handleability can be
obtained.
[0155] Further, the amount of the polymerization catalyst (D) is
0.001 to 20 mol %, preferably 0.005 to 15 mol %, and more
preferably 0.01 to 10 mol %, based on 1 mol of the repeating unit
represented by the following formula, which is a main structural
unit of the poly (phenylene ether ether ketone) oligomer (B).
##STR00005##
[0156] The molding material of the present invention is a molding
material comprising a composite of a continuous reinforcing fiber
bundle (A) and a poly (phenylene ether ether ketone) oligomer (B)
or poly (phenylene ether ether ketone) (B'), and a thermoplastic
resin (C) configured to adhere to the composite.
[0157] The reinforcing fiber bundle (A) and the poly (phenylene
ether ether ketone) oligomer (B) or poly (phenylene ether ether
ketone) (B') together form a composite. The configuration of the
composite is as shown in FIG. 1; the space between monofilaments of
the reinforcing fiber bundle (A) is filled with the poly (phenylene
ether ether ketone) oligomer (B) or poly (phenylene ether ether
ketone) (B'). In other words, the reinforcing fibers (A) are
dispersed like islands in the sea of the poly (phenylene ether
ether ketone) oligomer (B) or poly (phenylene ether ether ketone)
(B'). Further, the polymerization catalyst (D), in order to perform
its function, is preferably located in the sea of the poly
(phenylene ether ether ketone) oligomer (B) or poly (phenylene
ether ether ketone) (B') and/or at the interface between the
reinforcing fiber bundle (A) and the poly (phenylene ether ether
ketone) oligomer (B) or poly (phenylene ether ether ketone)
(B').
[0158] In the molding material of the present invention, by using a
composite of a poly (phenylene ether ether ketone) oligomer (B) or
poly (phenylene ether ether ketone) (B') with excellent heat
resistance and a reinforcing fiber bundle (A) satisfactorily
impregnated therewith, even if the composite is adhered to a
thermoplastic resin (C), for example when the molding material of
the present invention is injection molded, the poly (phenylene
ether ether ketone) oligomer (B) or poly (phenylene ether ether
ketone) (B') melt-kneaded in a cylinder of an injection molding
machine spreads into the thermoplastic resin (C), which helps the
reinforcing fiber bundle (A) disperse into the thermoplastic resin
(C). Further, the poly (phenylene ether ether ketone) oligomer (B)
or poly (phenylene ether ether ketone) (B') is readily replaced
with the thermoplastic resin (C), which allows the reinforcing
fiber bundle (A) to be more readily dispersed. In view of such an
effect, the poly (phenylene ether ether ketone) oligomer (B) or
poly (phenylene ether ether ketone) (B') acts as a so-called
impregnation aid/dispersion aid.
[0159] In the first and second preferred embodiments of the molding
material of the present invention, as shown in FIG. 2, the
reinforcing fiber bundle (A) is arranged substantially parallel to
the direction of the shaft center of the molding material, and the
length of the reinforcing fiber bundle (A) is substantially the
same as the length of the molding material.
[0160] The phrase "arranged substantially parallel" as used herein
refers to a state in which the major axis of the reinforcing fiber
bundle and the major axis of the molding material are oriented in
the same direction. The angular difference between the axes is
preferably 20.degree. or less, more preferably 10.degree. or less,
and still more preferably 5.degree. or less. The phrase
"substantially the same length" means that, for example, in a
pelleted molding material, a reinforcing fiber bundle is not broken
halfway inside the pellet, or the molding material is substantially
free of reinforcing fiber bundles that are significantly shorter
than the full-length of the pellet. The amount of the reinforcing
fiber bundle that are shorter than the full-length of the pellet is
not particularly defined, but when the content of the reinforcing
fiber having a length that is 50% or less of the full-length of the
pellet is not more than 30 wt %, the molding material is evaluated
to be substantially free of reinforcing fiber bundles that are
significantly shorter than the full-length of the pellet. Further,
the content of the reinforcing fiber having a length that is 50% or
less of the full-length of the pellet is preferably not more than
20 wt %. "Full-length of the pellet" refers to the length in the
orientation direction of the reinforcing fiber in the pellet. When
the reinforcing fiber bundle (A) has a length equivalent to that of
the molding material, the reinforcing fiber length in the molded
article can be long, and, consequently, excellent dynamic
properties can be provided.
[0161] FIGS. 3 to 6 schematically show examples of configurations
of cross-sections of the molding material of the present invention
in the direction of the shaft center, and FIGS. 7 to 10
schematically show examples of configurations of cross-sections of
the molding material of the present invention in the orthogonal
direction.
[0162] The configuration of the cross-section of the molding
material is not limited to those shown in the figures as long as a
thermoplastic resin (C) is configured to adhere to a composite of a
reinforcing fiber bundle (A) and a poly (phenylene ether ether
ketone) oligomer (B) or poly (phenylene ether ether ketone) (B').
Preferably, as shown in FIGS. 3 to 5 showing cross-sections in the
direction of the shaft center, configurations in which a composite
serving as a core is sandwiched between thermoplastic resins (C) in
layers are preferred.
[0163] Also, as shown in FIGS. 7 to 9 showing cross-sections in the
orthogonal direction, configurations in which such a core-sheath
structure is formed that a composite serving as a core is
surrounded by a thermoplastic resin (C) are preferred. In the case
of a configuration in which a thermoplastic resin (C) covers a
plurality of composites as shown in FIG. 11, the number of
composites is preferably about 2 to 6.
[0164] Alternatively, in the vicinity of an adhered boundary
between a composite and a thermoplastic resin (C), the
thermoplastic resin (C) may partially penetrate into part of the
composite to be compatible with the poly (phenylene ether ether
ketone) oligomer (B) or poly (phenylene ether ether ketone) (B') in
the composite or to impregnate into reinforcing fibers.
[0165] In the direction of the shaft center of the molding
material, it is only required that the cross-sectional shape be
maintained substantially the same and continuous. Depending on the
molding method, such a continuous molding material may be cut to a
certain length.
[0166] The molding material of the present invention can be formed
into a final molded article by blending a composite of a
reinforcing fiber bundle (A) and a poly (phenylene ether ether
ketone) oligomer (B) or poly (phenylene ether ether ketone) (B')
with a thermoplastic resin (C) using a method, e.g., injection
molding or press molding. In view of handleability of the molding
material, it is important that until molding, the composite and the
thermoplastic resin (C) not be separated and the configuration as
mentioned above be maintained. The poly (phenylene ether ether
ketone) oligomer (B) has a low molecular weight, and therefore, in
most cases, it is generally a solid that is relatively fragile and
easily broken at normal temperature. Accordingly, the thermoplastic
resin (C) is preferably configured to protect the composite so that
the poly (phenylene ether ether ketone) oligomer (B) is not broken
and scattered, for example, by material transportation before
molding, impact of handling, and abrasion. Further, the composite
and the thermoplastic resin (C) have a different configuration
(size, aspect ratio), specific gravity, and weight, and, therefore,
may be separated during material transportation before molding,
handling, or material transfer in a molding process, which can
cause variation in dynamic properties of molded articles, or
decrease the fluidity to cause mold clogging or blocking in the
molding process.
[0167] Thus, it is preferred that, as shown in FIGS. 7 to 9, the
thermoplastic resin (C) be configured to surround the composite of
a reinforcing fiber bundle (A), which is reinforcing fibers, and a
poly (phenylene ether ether ketone) oligomer (B) or poly (phenylene
ether ether ketone) (B'). In other words, it is preferred that the
composite of a reinforcing fiber bundle (A), which is reinforcing
fibers, and a poly (phenylene ether ether ketone) oligomer (B) or
poly (phenylene ether ether ketone) (B') forms a core structure,
and the thermoplastic resin (C) surround the composite to form a
core-sheath structure.
[0168] In such a configuration, a high-molecular-weight
thermoplastic resin (C) wraps around the poly (phenylene ether
ether ketone) oligomer (B) that is easily broken, or the
thermoplastic resin (C) is disposed on a surface that is easily
abraded; therefore, the molding material is likely to maintain its
shape, and the composite and the thermoplastic resin (C) can be
firmly combined. Regarding which configuration is advantageous,
i.e., the configuration in which the thermoplastic resin (C) is
configured to surround the composite of a reinforcing fiber bundle
(A) and a poly (phenylene ether ether ketone) oligomer (B) or poly
(phenylene ether ether ketone) (B') or the configuration in which
the composite and the thermoplastic resin (C) are arranged in
layers, the configuration in which the thermoplastic resin (C) is
configured to surround the composite is more preferred in terms of
the ease of production and handleability of materials.
[0169] As mentioned above, it is desired that the reinforcing fiber
bundle (A) be completely impregnated with the poly (phenylene ether
ether ketone) oligomer (B) or poly (phenylene ether ether ketone)
(B'). However, that is practically difficult, and some voids are
present in the composite of the reinforcing fiber bundle (A) and
the poly (phenylene ether ether ketone) oligomer (B) or poly
(phenylene ether ether ketone) (B'). The number of voids increases
particularly when the content of the reinforcing fiber bundle (A)
is large, but the impregnation/fiber dispersion-promoting effect
according to the present invention is exhibited even when some
voids are present. However, the impregnation/fiber
dispersion-promoting effect significantly decreases when a void
fraction is more than 40%. Thus, the void fraction is preferably in
the range of 0 to 40%, and more preferably in the range of 20% or
less. The void fraction is determined by measuring a composite part
according to ASTM D2734 test method (1997).
[0170] The molding material of the present invention is preferably
cut to a length in the range of 1 to 50 mm when used. By adjusting
the length within such a range, fluidity and handleability during
molding can be sufficiently improved. Examples of particularly
preferred forms of the molding material cut to such an appropriate
length include a long-fiber pellet for injection molding.
[0171] The molding material of the present invention can also be
used in a continuous or long form depending on the molding method.
For example, the molding material in the form of a thermoplastic
yarn prepreg can be wound around a mandrel with heating to obtain
roll molded article. Examples of such molded articles include a
liquefied natural gas tank. Also, a plurality of the molding
materials of the present invention can be unidirectionally aligned
and heat-fused to produce a unidirectional thermoplastic prepreg.
Such a prepreg is applicable in fields that require high strength,
elastic modulus, and impact resistance, for example, to aircraft
members.
<Method for Producing Molding Material>
[0172] In the second preferred embodiment, the molding material of
the present invention comprises a reinforcing fiber bundle (A), a
poly (phenylene ether ether ketone) (B'), a thermoplastic resin
(C), and a polymerization catalyst (D), and the molding material is
preferably produced via the steps [i] to [iii] below because the
configurations mentioned above can be easily formed.
[0173] Step [i]: Producing a mixture of a poly (phenylene ether
ether ketone) oligomer (B) and a polymerization catalyst (D).
[0174] Step [ii]: Forming a composite of the mixture and a
continuous reinforcing fiber bundle (A) impregnated therewith.
[0175] Step [iii]: Adhering the composite to a thermoplastic resin
(C).
<Step [i]>
[0176] In the step [i], an apparatus for producing a mixture may be
any apparatus that is equipped with a mechanism for mixing the poly
(phenylene ether ether ketone) oligomer (B) and the polymerization
catalyst (D) loaded, but the apparatus is preferably equipped with
a heating source for heat-melting the poly (phenylene ether ether
ketone) oligomer (B) in order to uniformly mix the poly (phenylene
ether ether ketone) oligomer (B) and the polymerization catalyst
(D). Further, to quickly proceed to the step [ii] after producing a
molten mixture, the apparatus is preferably equipped with a
delivery mechanism. Examples of drive systems for delivery include
gravity-feed system, pressure-feed system, screw system, and pump
system.
[0177] In the step [i], when producing a molten mixture, it is
preferable to set the temperature and time such that thermal
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) occurs as little as possible. The temperature for producing a
molten mixture is 160 to 340.degree. C., preferably 180 to
320.degree. C., more preferably 200 to 300.degree. C., and
particularly preferably 230 to 270.degree. C. When a molten mixture
is produced in this preferred temperature range, the poly
(phenylene ether ether ketone) oligomer (B) can be melted in a
short time, and at the same time, viscosity increase due to
formation of poly (phenylene ether ether ketone)s (B') is unlikely
to occur because thermal polymerization of the poly (phenylene
ether ether ketone) oligomer (B) can be reduced.
[0178] In the step [i], the time for producing a molten mixture is
not critical, but to avoid thickening due to the progress of
polymerization of the poly (phenylene ether ether ketone) oligomer
(B), it is preferable to proceed to the step [ii] as quickly as
possible after heating the poly (phenylene ether ether ketone)
oligomer (B) and the polymerization catalyst (D). The time is in
the range of 0.01 to 300 minutes, preferably 0.1 to 60 minutes,
more preferably 0.3 to 30 minutes, and still more preferably 0.5 to
10 minutes. When the heating time is in this preferred range,
dispersion of the polymerization catalyst (D) in the poly
(phenylene ether ether ketone) oligomer (B) is sufficient, and at
the same time, thermal polymerization of the poly (phenylene ether
ether ketone) oligomer (B) can be reduced.
[0179] The heating is preferably performed in a non-oxidizing
atmosphere or under reduced-pressure conditions. Here,
"non-oxidizing atmosphere" refers to an atmosphere of inert gas
such as nitrogen, helium, and argon. "Under reduced-pressure
conditions" means that the pressure in the system is lower than
atmospheric pressure, and, for example, the range of 0.1 kPa to 50
kPa is a preferred range. Such conditions tend to inhibit the
occurrence of undesirable side reactions such as cross-linking
reaction and decomposition reaction, for example, between the poly
(phenylene ether ether ketone) oligomers (B), between the poly
(phenylene ether ether ketone)s (B') formed by heating, and between
the poly (phenylene ether ether ketone) (B') and the poly
(phenylene ether ether ketone) oligomer (B).
<Step [ii]>
[0180] In the step [ii], any apparatus may be used which is
equipped with a mechanism for impregnating the mixture obtained in
the step [i] into a continuous reinforcing fiber bundle (A), and
examples thereof include an apparatus for feeding a molten mixture
to a mold die such as a T-die or a slit die while passing a
reinforcing fiber bundle through the mold die, an apparatus for
feeding a molten mixture to a molten bath with a gear pump and
passing a reinforcing fiber bundle (A) with drawing through the
molten bath, an apparatus for feeding a molten mixture to a kiss
coater with a plunger pump to apply to a reinforcing fiber bundle
(A), and the method of feeding a molten mixture onto a heated
rotating roll and passing a reinforcing fiber bundle (A) over the
roll surface. These apparatuses may be used in combination in order
to improve impregnation properties, and the composite obtained may
be passed through the same apparatus more than once in loops.
[0181] In the step [ii], the temperature during impregnation of a
melt-kneaded product is 160 to 450.degree. C., preferably 200 to
400.degree. C., more preferably 230 to 350.degree. C., and
particularly preferably 270 to 300.degree. C. When the temperature
during impregnation of a melt-kneaded product in this preferred
range, the poly (phenylene ether ether ketone) oligomer (B) is not
readily coagulated, thickened, or solidified, providing excellent
impregnation properties, and at the same time, undesirable side
reactions such as cross-linking reaction and decomposition reaction
are unlikely to occur, for example, between the poly (phenylene
ether ether ketone) oligomers (B), between the poly (phenylene
ether ether ketone)s (B) formed by heating, and between the poly
(phenylene ether ether ketone) oligomer (B) and the poly (phenylene
ether ether ketone) (B').
[0182] In the step [ii], the time for impregnation of a
melt-kneaded product is not critical, but it is preferable to
secure the time enough for the melt-kneaded product to sufficiently
impregnate into a reinforcing fiber bundle (A). The time is in the
range of 0.001 to 1,000 minutes, preferably 0.01 to 300 minutes,
more preferably 0.1 to 60 minutes, still more preferably 0.3 to 30
minutes, and particularly preferably 0.5 to 10 minutes. When the
impregnation time is in this preferred range, impregnation of a
melt-kneaded product into a reinforcing fiber bundle (A) is
sufficient, and at the same time, the molding material can be
produced efficiently.
<Step [iii]>
[0183] In the step [iii], any apparatus may be used which is
equipped with a mechanism for adhering a thermoplastic resin (C) to
the composite obtained in the step [ii], and examples thereof
include an apparatus for feeding a molten thermoplastic resin (C)
to a mold die such as a T-die or a slit die while passing the
composite through the mold die, an apparatus for feeding a molten
thermoplastic resin (C) to a molten bath with a gear pump and
passing the composite through the molten bath, an apparatus for
feeding a molten thermoplastic resin (C) to a kiss coater with a
plunger pump to apply to the composite, and the method of feeding a
molten thermoplastic resin (C) onto a heated rotating roll and
passing the composite over the roll surface.
[0184] In the step [iii], the temperature for adhering the
composite to a thermoplastic resin (C) cannot be generalized
because it varies depending on the properties of the thermoplastic
resin (C) used, such as molecular structure, molecular weight, and
composition, but the lower limit is, for example, the melting point
of the thermoplastic resin (C) used. The upper limit is, for
example, the melting point described above, further, 80.degree. C.,
preferably 50.degree. C., more preferably 30.degree. C., and still
more preferably 20.degree. C. In such a temperature range, the
thermoplastic resin (C) can be easily adhered to the composite, and
phenomena that are undesirable for production can be prevented,
such as thermal decomposition of the thermoplastic resin (C). The
melting point of the thermoplastic resin (C) can be measured by
observing an endothermic peak temperature using a differential
scanning calorimeter.
[0185] In the step [iii], the time over which the composite passes
through an apparatus for adhering the composite to a thermoplastic
resin is not critical, but it is, for example, 0.0001 to 120
minutes, preferably 0.001 to 60 minutes, and more preferably 0.01
to 10 minutes. When the time over which the composite passes
through the adhesion apparatus is in this preferred range, the
composite easily adheres to a thermoplastic resin, and at the same
time, the molding material can be produced efficiently.
[0186] In the production process of the molding material of the
present invention, conversion of a poly (phenylene ether ether
ketone) oligomer (B) into a poly (phenylene ether ether ketone)
(B') may be carried out in any of the steps [i] to [iii], but to
efficiently carry out the impregnation of the poly (phenylene ether
ether ketone) oligomer (B) into a reinforcing fiber bundle (A), it
is preferable to selectively polymerize the poly (phenylene ether
ether ketone) oligomer (B) simultaneously with and after the step
[ii]. Also to satisfy such requirements, the above-described
conditions such as apparatus, temperature, and time in the steps
[i] to [iii] are preferred.
[0187] Further, it is also significant to further perform a heat
treatment at 160 to 450.degree. C., preferably 200 to 400.degree.
C., more preferably 230 to 350.degree. C., and particularly
preferably at 270 to 300.degree. C. after the steps [i] to [iii] to
thermally polymerize the poly (phenylene ether ether ketone)
oligomer (B) remaining in the molding material. When the heat
treatment is carried out at a temperature lower than 160.degree.
C., the polymerization of the poly (phenylene ether ether ketone)
oligomer (B) does not proceed well and a long time may be required.
When the heat treatment is carried out at a temperature higher than
450.degree. C., the thermoplastic resin (C) can melt in a short
time, which results in loss of configuration of the molding
material.
<Method for Producing Molded Article>
[0188] In the first preferred embodiment, the molding material of
the present invention comprises a reinforcing fiber bundle (A), a
poly (phenylene ether ether ketone) oligomer (B), and a
thermoplastic resin (C). Since the poly (phenylene ether ether
ketone) oligomer (B) has a low melting point, it has excellent
processability in impregnation into the reinforcing fiber bundle
(A), and a composite of the reinforcing fiber bundle (A) and the
poly (phenylene ether ether ketone) oligomer (B) can be easily
produced, which is effective in improving the productivity of the
molding material. Further, since the poly (phenylene ether ether
ketone) oligomer (B) also has excellent fluidity, when the molding
material of the present invention is injection molded, for example,
the poly (phenylene ether ether ketone) oligomer (B) having
excellent fluidity melt-kneaded in a cylinder of an injection
molding machine spreads into the thermoplastic resin (C), which
helps the reinforcing fiber bundle (A) disperse into the
thermoplastic resin (C). Further, the poly (phenylene ether ether
ketone) oligomer (B) is readily replaced with the thermoplastic
resin (C), which allows the reinforcing fiber bundle (A) to be more
readily dispersed. In view of such an effect, the poly (phenylene
ether ether ketone) oligomer (B) acts as a so-called impregnation
aid/dispersion aid.
[0189] Further, in the present invention, the polymerization
catalyst (D) serves as a so-called polymerization catalyst which
promotes thermal conversion of the poly (phenylene ether ether
ketone) oligomer (B) into a poly (phenylene ether ether ketone)
(B'). In producing a molded article by molding the molding material
of the present invention comprising a reinforcing fiber bundle (A),
a poly (phenylene ether ether ketone) oligomer (B), a thermoplastic
resin (C), and a polymerization catalyst (D), the poly (phenylene
ether ether ketone) oligomer (B) can be thermally polymerized in
the presence of the polymerization catalyst (D) to convert into a
poly (phenylene ether ether ketone) (B'). Due to such an effect of
the polymerization catalyst (D), for example, when the molding
material of the present invention comprising the polymerization
catalyst (D) is injection molded, polymerization of the poly
(phenylene ether ether ketone) oligomer (B) into a poly (phenylene
ether ether ketone) (B') proceeds in a cylinder and a mold in an
injection molding process, and a molded article having excellent
dynamic properties can be obtained.
[0190] The molding material of the present invention can be formed
into a predetermined shape by melting by heat. The temperature for
melting the molding material varies depending on the raw materials
selected, but it is preferably in the range of 160.degree. C. to
450.degree. C., more preferably 230.degree. C. to 430.degree. C.,
and still more preferably 270.degree. C. to 400.degree. C., for
example. When the temperature is lower than 160.degree. C., the
poly (phenylene ether ether ketone) oligomer (B) or poly (phenylene
ether ether ketone) (B') and/or the thermoplastic resin (C) may not
melt, causing a problem in moldability. When the temperature is
higher than 450.degree. C., the thermoplastic resin (C) may undergo
thermal decomposition, leading to reduction in physical properties
of a molded article or causing voids.
[0191] The molding material of the present invention can be
preheated before molding. The temperature for preheating the
molding material varies depending on the raw materials selected,
but it is, for example, 160.degree. C. to 450.degree. C., more
preferably 230.degree. C. to 400.degree. C., and still more
preferably 270.degree. C. to 400.degree. C. When the preheating is
performed in such a temperature range, thermal polymerization of
the poly (phenylene ether ether ketone) oligomer (B) into a poly
(phenylene ether ether ketone) (B') proceeds, which can be
effective in improving the dynamic properties of a molded article.
From the standpoint of productivity, the molding material subjected
to such a preheating process may be loaded directly into a molding
machine.
[0192] The molding material of the present invention may be
subjected to a pretreatment in addition to the preheating process
as long as the object of the present invention is achieved.
Examples of pretreatments include drying, degreasing, degassing,
cutting, shaping, lamination, arrangement, and adhesion.
[0193] The molding material of the present invention can be
processed into a molded article of final shape by various molding
methods. Examples of the molding method include press molding,
stampable molding, transfer molding, injection molding, and
combinations thereof.
[0194] The molding material of the present invention can be formed
into various shapes: e.g., molded articles of complex shape, such
as rib, boss, and gear; and molded articles with a broad width,
such as flat plate, square plate, and round plate. In the case of
molded articles of complex shape, injection molding and transfer
molding are preferably used, and injection molding is more
preferably used in terms of productivity. In the case of molded
articles with a broad width, press molding and stamping molding are
preferably used.
[0195] When the molding material of the present invention is used
for injection molding, it is preferable to use the molding material
in the form of pellets. In injection molding, temperature,
pressure, and kneading are applied when the pelleted molding
material is plasticized; therefore, according to the present
invention, the poly (phenylene ether ether ketone) oligomer (B) or
poly (phenylene ether ether ketone) (B') exerts a significant
effect as an impregnation/dispersion aid. In this case, a
conventional in-line screw injection molding machine can be used.
Even if the kneading effect of a screw is small because, for
example, a screw having a shape that provides a low compression
ratio is used or the back pressure during plasticization of the
material is set low, reinforcing fibers are satisfactorily
dispersed in a matrix resin, and a molded article in which fibers
are satisfactorily impregnated with resin can be obtained.
[0196] Further, a molded article obtained by molding the molding
material of the present invention can be heat treated. The
temperature at which the molded article is heated varies depending
on the raw materials used for the molding material, but it is, for
example, 160.degree. C. to 450.degree. C., more preferably
230.degree. C. to 430.degree. C., and still more preferably
270.degree. C. to 400.degree. C. When the heat treatment is
performed in such a temperature range, thermal polymerization of
the poly (phenylene ether ether ketone) oligomer (B) into a poly
(phenylene ether ether ketone) (B') proceeds, which can be
effective in improving the dynamic properties of the molded
article.
[0197] The molded article obtained by the present invention may be
subjected to a post-treatment in addition to the heating process as
long as the object of the present invention is achieved. Examples
of post-treatments include annealing, polishing, cutting, grinding,
adhesion, and painting.
<Prepreg>
[0198] In a third preferred embodiment, the molding material of the
present invention comprises a reinforcing fiber substrate (A'), a
poly (phenylene ether ether ketone) oligomer (B), and a
polymerization catalyst (D). The form of the molding material of
the present invention is not critical, but from the standpoint of
productivity and handleability, for example, the form of a prepreg
obtained by impregnating a substrate comprising the reinforcing
fiber substrate (A') with the poly (phenylene ether ether ketone)
oligomer (B) and the polymerization catalyst (D) is preferred.
[0199] The content of the reinforcing fiber substrate (A') is
preferably 30 wt % or more, more preferably 50 wt % or more, still
more preferably 60 wt % or more, and particularly preferably 70 wt
% or more, based on 100 wt % of the total of the reinforcing fiber
substrate (A') and the poly (phenylene ether ether ketone) oligomer
(B). When the content of the reinforcing fiber substrate (A') is
less than 30 wt %, the resulting molded article may have poor
dynamic properties. The upper limit of the content of the
reinforcing fiber substrate (A') is not limited, but it is
preferably not more than 90 wt %, more preferably not more than 80
wt %, and still more preferably not more than 70 wt %. When the
content of the reinforcing fiber substrate (A') is more than 90 wt
%, it can be difficult to impregnate the poly (phenylene ether
ether ketone) oligomer (B) into the reinforcing fiber substrate
(A'). The content of the reinforcing fiber substrate (A') in the
molding material of the present invention can be adjusted by
controlling the supply of the reinforcing fiber substrate (A') and
the poly (phenylene ether ether ketone) oligomer (B).
[0200] Further, the content of the polymerization catalyst (D) is
0.001 to 20 mol %, preferably 0.005 to 15 mol %, and more
preferably 0.01 to 10 mol %, based on 1 mol of the repeating unit
represented by the following formula, which is a main structural
unit of the poly (phenylene ether ether ketone) oligomer (B).
##STR00006##
[0201] Further, for the molding material of the present invention,
molding materials having different impregnation rates of the poly
(phenylene ether ether ketone) oligomer (B) can be produced
depending on the application and purpose. Examples thereof include
a prepreg with higher impregnation properties, a semi-impregnated
semipreg, and a fabric with low impregnation properties. In
general, a molding material with higher impregnation properties
tends to provide a molded article having excellent dynamic
properties by molding in a shorter time. In contrast, a molding
material with relatively low impregnation properties tends to be
excellent in drape property and shaping into, for example, a curved
shape.
[0202] Thus, in the molding material of the present invention, a
first preferred aspect of the impregnation rate of the poly
(phenylene ether ether ketone) oligomer (B) is a molding material
having an impregnation rate of 80% to 100%. This is advantageous in
terms of production of a molded article of simpler planar shape
with high productivity.
[0203] Further, in the molding material of the present invention, a
second preferred aspect of the impregnation rate of the poly
(phenylene ether ether ketone) oligomer (B) is a molding material
having an impregnation rate of 20% to less than 80%. This is a
molding material having excellent drape property, and the molding
material can be shaped in advance to a mold, which is advantageous
in terms of production of a molded article of relatively complex
shape such as curved shape with high productivity.
[0204] "Impregnation rate of the poly (phenylene ether ether
ketone) oligomer (B)" as used herein is expressed as a percentage
(%) obtained by observing a cross-section of the molding material
using a light microscope and dividing the area of impregnation of
the poly (phenylene ether ether ketone) oligomer (B) by the total
of the area of impregnation and the area of voids.
[0205] Examples of means for controlling the impregnation rate
include temperature and pressure in combining the poly (phenylene
ether ether ketone) oligomer (B) with the reinforcing fiber
substrate (A'). In general, the higher the temperature and the
pressure are, the greater the effect of increasing the impregnation
rate is. The lower the melt viscosity of the poly (phenylene ether
ether ketone) oligomer (B) is, the more the impregnation properties
can be enhanced.
[0206] To the poly (phenylene ether ether ketone) oligomer (B) in
the third preferred embodiment of the molding material of the
present invention, polymers or oligomers of various thermoplastic
resins, various thermosetting resins, impact-resistance improvers
such as elastomers or rubber components, inorganic fillers, flame
retardants, conductivity-imparting agents, crystal nucleating
agents, UV absorbers, antioxidants, vibration dampers,
antimicrobial agents, insect repellents, deodorizers, stain
inhibitors, heat stabilizers, mold releasing agents, antistatic
agents, plasticizers, lubricants, coloring agents, pigments, dyes,
foaming agents, foam suppressors, coupling agents, or the like may
be added as long as the object of the present invention is
achieved.
[0207] Specific examples of thermoplastic resins include polyester
resins such as polyethylene terephthalate (PET) resin, polybutylene
terephthalate (PBT) resin, polytrimethylene terephthalate (PTT)
resin, polyethylene naphthalate (PENp) resin, and liquid crystal
polyester; polyolefin resins such as polyethylene (PE) resin,
polypropylene (PP) resin, and polybutylene resin; styrene resins;
urethane resins; further, polyoxymethylene (POM) resin, polyamide
(PA) resin, polycarbonate (PC) resin, polymethyl methacrylate
(PMMA) resin, polyvinyl chloride (PVC) resin, polyphenylene sulfide
(PPS) resin, polyphenylene ether (PPE) resin, modified PPE resin,
polyimide (PI) resin, polyamide-imide (PAI) resin, polyetherimide
(PEI) resin, polysulfone (PSU) resin, modified PSU resin,
polyethersulfone (PES) resin, polyketone (PK) resin, polyether
ketone (PEK) resin, polyether ether ketone (PEEK) resin, polyether
ketone ketone (PEKK) resin, polyarylate (PAR) resin, polyether
nitrile (PEN) resin, phenol resin, phenoxy resin, fluorine resins
such as polytetrafluoroethylene; and copolymers, modifications, and
resin blends of two or more thereof.
[0208] Specific examples thermosetting resins include unsaturated
polyester resins, vinyl ester resins, epoxy resins, and phenol
resins.
[0209] To facilitate the lamination of the molding material, it is
also preferable to add a tackifier. As a tackifier, a compound with
a softening temperature of 150.degree. C. or lower having a polar
group in its molecule is suitably used. "Softening temperature"
refers to a Vicat softening temperature defined in JIS K 7206-1999.
Compounds with a softening temperature of 150.degree. C. or lower
are preferred because they have a relatively small molecular weight
and good fluidity to improve the stickiness in lamination of the
molding material; and compounds having a polar group in their
molecules are also preferred because they induce weak bonding such
as hydrogen bonding to improve the stickiness in lamination of the
molding material. Specifically, ethylene-ethyl acrylate copolymer,
ethylene-vinyl acrylate copolymer, terpene polymer, terpene phenol
copolymer, polyurethane elastomer, acrylonitrile-butadiene rubber
(NBR), and the like are suitably used.
<Method for Producing Prepreg>
[0210] The molding material of the present invention in the third
preferred embodiment can be produced, for example, by the wet
method in which a poly (phenylene ether ether ketone) oligomer (B)
and a polymerization catalyst (D) are dissolved or dispersed in a
solvent to reduce the viscosity and impregnated into a reinforcing
fiber substrate (A'), or the hot-melt method in which a mixture of
a poly (phenylene ether ether ketone) oligomer (B) and a
polymerization catalyst (D) is heated to reduce the viscosity and
impregnated into a reinforcing fiber substrate (A').
[0211] The wet method is a method for obtaining a molding material
comprising immersing a reinforcing fiber substrate (A') in a
solution or dispersion of a poly (phenylene ether ether ketone)
oligomer (B) and a polymerization catalyst (D), pulling it up, and
evaporating the solvent using an oven or the like.
[0212] The hot-melt method is a method for obtaining a molding
material, for example, by applying a molten mixture of a poly
(phenylene ether ether ketone) oligomer (B) and a polymerization
catalyst (D), the viscosity of which mixture is reduced by heating,
directly to a reinforcing fiber substrate (A') and performing
hot-pressing for impregnation, or by coating release paper or the
like with a molten mixture of a poly (phenylene ether ether ketone)
oligomer (B) and a polymerization catalyst (D) to prepare a resin
film, laminating the film(s) on both sides or one side of a
reinforcing fiber substrate (A'), and performing hot-pressing for
impregnation. The hot-melt method does not use a solvent;
therefore, resin viscosity needs to be reduced to some extent in
the process of impregnation into a reinforcing fiber substrate
(A'), but that is preferred because substantially no solvent
remains in the molding material.
[0213] When the molding material of the present invention is
produced by the hot-melt method, in the step of producing a molten
mixture of a poly (phenylene ether ether ketone) oligomer (B) and a
polymerization catalyst (D) and the step of impregnating the molten
mixture into a reinforcing fibers (A), it is preferable to set the
temperature and time such that thermal polymerization of the poly
(phenylene ether ether ketone) oligomer (B) occurs as little as
possible. The temperature in the step of producing a molten mixture
and the step of impregnating the molten mixture is 160 to
340.degree. C., preferably 180 to 320.degree. C., more preferably
200 to 300.degree. C., and particularly preferably 230 to
270.degree. C. When the temperature is in this preferred range, the
poly (phenylene ether ether ketone) oligomer (B) can be melted in a
short time, and at the same time, viscosity increase due to
formation of poly (phenylene ether ether ketone)s (B') is unlikely
to occur.
[0214] The time spent on the step of producing a molten mixture and
the step of impregnating the molten mixture is not critical, but to
avoid thickening due to the progress of polymerization of the poly
(phenylene ether ether ketone) oligomer (B), it is preferable to
proceed to the next step as quickly as possible after heating the
poly (phenylene ether ether ketone) oligomer (B) and the
polymerization catalyst (D). The time is in the range of 0.01 to
300 minutes, preferably 0.1 to 60 minutes, more preferably 0.3 to
30 minutes, and still more preferably 0.5 to 10 minutes. When the
heating time in this preferred range, dispersion of the
polymerization catalyst (D) in the poly (phenylene ether ether
ketone) oligomer (B) is sufficient, and at the same time, viscosity
increase due to formation of poly (phenylene ether ether ketone)s
(B') is unlikely to occur.
[0215] The heating is preferably performed in a non-oxidizing
atmosphere or under reduced-pressure conditions. Here,
"non-oxidizing atmosphere" refers to an atmosphere of inert gas
such as nitrogen, helium, and argon. "Under reduced-pressure
conditions" means that the pressure in the system is lower than
atmospheric pressure, and, for example, the range of 0.1 kPa to 50
kPa is a preferred range. Such conditions tend to inhibit the
occurrence of undesirable side reactions such as cross-linking
reaction and decomposition reaction, for example, between the poly
(phenylene ether ether ketone) oligomers (B), between the poly
(phenylene ether ether ketone)s (B') formed by heating, and between
the poly (phenylene ether ether ketone) (B') and the poly
(phenylene ether ether ketone) oligomer (B).
[0216] In the molding material of the present invention, to obtain
a molding material that has a high impregnation rate of the poly
(phenylene ether ether ketone) oligomer (B) and provides a molded
article with high dynamic properties, it is preferable to apply
pressure in the step of impregnating a molten mixture. Such
pressure is preferably in the range of 0.1 to 10 MPa, and more
preferably in the range of 0.2 to 5 MPa, for example.
[0217] In the molding material of the present invention, to obtain
a molding material having a relatively reduced impregnation rate of
the poly (phenylene ether ether ketone) oligomer (B) and excellent
moldability, it is preferable to apply almost no pressure in the
step of impregnating a molten mixture. Such pressure is preferably
in the range of 0 to 0.1 MPa, and more preferably in the range of
0.01 to 0.05 MPa, for example. Alternatively, it is also preferable
to use the method comprising once applying pressure and then
removing the pressure before the poly (phenylene ether ether
ketone) oligomer (B) is cooled and solidified. Examples of the
pressure device used to apply pressure include, but are not limited
to, pressing machines and rollers.
<Method for Molding Prepreg>
[0218] In the third preferred embodiment of the molding material of
the present invention, at least one layer of the molding material
is laminated in any configuration, and then the poly (phenylene
ether ether ketone) oligomer (B) is polymerized while applying heat
and pressure to obtain a molded article comprising a poly
(phenylene ether ether ketone) (B') as a matrix resin.
[0219] Examples of methods of applying heat and pressure that can
be used include the press molding method in which the molding
material laminated in any configuration is placed in a mold or on a
pressing plate, and then the mold or the pressing plate is closed
and pressurized; the autoclave molding method in which the molding
material laminated in any configuration is charged into an
autoclave, and pressurized and heated; the bag-molding method in
which the molding material laminated in any configuration is
wrapped with a film or the like and, with the internal pressure
reduced, heated in an oven while being pressurized at atmospheric
pressure; the wrapping tape method in which the molding material
laminated in any configuration is wrapped with tape under tension
and heated in an oven; and the internal pressure molding method in
which the molding material laminated in any configuration is placed
in a mold, and a core that is also placed in the mold is charged
with gas or liquid and pressurized. In particular, molding methods
in which pressing is performed using a mold are preferred because a
molded article with low void and excellent appearance quality can
be obtained.
[0220] The lower limit of the heating temperature during molding
is, for example, not lower than 160.degree. C., preferably not
lower than 200.degree. C., more preferably not lower than
230.degree. C., and still more preferably not lower than
270.degree. C. In this temperature range, it is likely that the
poly (phenylene ether ether ketone) oligomer (B) will melt and a
poly (phenylene ether ether ketone) (13') can be obtained in a
short time.
[0221] The upper limit of the heating temperature during molding
is, for example, not higher than 450.degree. C., preferably not
higher than 400.degree. C., more preferably not higher than
350.degree. C., and still more preferably not higher than
300.degree. C. When the heating temperature is not higher than this
temperature range, it is likely that adverse effects of undesirable
side reactions on the properties of the poly (phenylene ether ether
ketone) (B') can be prevented.
[0222] Further, the molding material of the present invention is
preferably molded at a temperature not higher than the melting
point of the poly (phenylene ether ether ketone) (B'). This is a
molding method taking advantages of crystallization polymerization
of the poly (phenylene ether ether ketone) oligomer (B) in the
present invention, which molding method is excellent in that
thermal polymerization of the poly (phenylene ether ether ketone)
oligomer (B) and crystallization of the poly (phenylene ether ether
ketone) (B') proceed simultaneously during molding, whereby
demolding of a molded article can be carried out with a
mold-cooling process shortened, which process is necessary in
molding of an ordinary thermoplastic resin prepreg.
[0223] Examples of the method here for measuring the heating
temperature during molding include, in the case of a molding method
in which molding is performed using a mold, measuring the surface
temperature of the mold using a thermometer such as a
thermocouple.
[0224] The pressure during molding is preferably in the range of
0.1 to 10 MPa, and more preferably in the range of 0.2 to 5 MPa,
for example. When the pressure during molding is in this preferred
range, voids will not occur in a large amount in the resulting
molded article, and at the same time, the arrangement of the
reinforcing fibers (A) will not be greatly disarranged.
[0225] The time for performing hot-pressing during molding is not
critical, but it is in the range of 0.001 to 1,000 minutes,
preferably 0.01 to 300 minutes, more preferably 0.1 to 60 minutes,
still more preferably 0.3 to 30 minutes, and particularly
preferably 0.5 to 10 minutes. When the impregnation time is in this
preferred range, polymerization of the poly (phenylene ether ether
ketone) oligomer (B) into a poly (phenylene ether ether ketone)
(B') sufficiently occurs, and at the same time, the molding
material can be produced efficiently.
<Method for Producing Molding Material>
[0226] In a fourth preferred embodiment, the molding material of
the present invention comprises a reinforcing fiber substrate (A'),
a poly (phenylene ether ether ketone) (B'), and a polymerization
catalyst (D). The method for producing this molding material
comprises at least the following steps.
[0227] Step [I]: Drawing and continuously feeding a reinforcing
fiber substrate (A').
[0228] Step [II]: Combining the reinforcing fiber substrate (A')
with a poly (phenylene ether ether ketone) oligomer (B) to form a
composite.
[0229] Step [III]: Polymerizing the poly (phenylene ether ether
ketone) oligomer (B) into a poly (phenylene ether ether ketone)
(B').
[0230] Step [IV]: Cooling and taking up the composite of the
reinforcing fiber substrate (A') and the poly (phenylene ether
ether ketone) (B').
[0231] Further, the method for producing a molding material of the
present invention is characterized in that the poly (phenylene
ether ether ketone) oligomer (B) used in the step [II] has a
melting point of not higher than 270.degree. C.
[0232] From the standpoint of productivity, in the step [II] of the
method for producing a molding material of the present invention,
it is preferable to add a polymerization catalyst (D) to the poly
(phenylene ether ether ketone) oligomer (B) to promote the
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) into a poly (phenylene ether ether ketone) (B').
[0233] Although each step can be performed off-line, it is
preferable to perform the steps [I] to [IV] on-line in terms of
economic efficiency and productivity.
[0234] "Performing the steps [I] to [IV] on-line" means that all
the steps [I] to [IV] are carried out successively or
intermittently in a continuous production line (see, for example,
FIGS. 13 to 15).
[0235] Description will be given for each step.
<Step [I]>
[0236] The step [I] is a step of feeding a reinforcing fiber
substrate (A') to a production line. To produce a molding material
with high economic efficiency and productivity, the reinforcing
fiber substrate (A') is preferably fed continuously. "Continuous"
means that the reinforcing fiber substrate (A') which is a raw
material is fed unceasingly without a complete break. The feed rate
may be constant, or feeding and cessation may be repeated
intermittently. Further, to improve the shapability of the
resulting molding material, the step [I] may comprise cutting a
part of the reinforcing fiber substrate (A') to provide a slit.
[0237] The step [I] is also intended to draw the reinforcing fiber
substrate (A') and dispose it in a given arrangement. Namely, the
reinforcing fiber substrate (A') to be fed may be in the form of a
yarn, unidirectionally align sheet, or preform which is
preliminarily shaped. Specifically, for example, a plurality of
reinforcing fiber bundles is unidirectionally arranged in the form
of a sheet, further passed through a roll bar, and fed to the
production line; alternatively, a reinforcing fiber substrate (A')
preliminarily rolled up in the form a fabric, nonwoven fabric, or
mat is mounted on a creel, drawn, passed through a roller, and fed
to the production line. Methods using a roll are preferably used
because a large amount of molding material can be produced at a
time. Alternatively, for example, the reinforcing fiber substrate
(A') is passed through a plurality of roll bars arranged so as to
form a given shape and fed to the production line. Further, when
the reinforcing fiber substrate (A') is processed in a planar form,
it may be fed directly to the production line from, for example, a
twisted and wound state. Further, providing rollers or roll bars
with a drive allows, for example, adjustment of feed rate, which is
more preferred in terms of production control.
[0238] Further, in terms of productivity, the step [I] preferably
comprises heating the reinforcing fiber substrate (A') at 50 to
500.degree. C., preferably 80 to 400.degree. C., and more
preferably 100 to 300.degree. C. Heating the reinforcing fiber
substrate (A') improves fixation of a poly (phenylene ether ether
ketone) oligomer (B) to the reinforcing fiber substrate (A') in the
step [II]. Also, a sizing agent or the like applied to the
reinforcing fiber substrate (A') can be softened for opening.
Examples of the heating method include, but are not limited to,
noncontact heating with hot air or an infrared heater and contact
heating with a pipe heater or by electromagnetic induction.
[0239] Further, the step [I] more preferably comprises opening
operation, for example, when the reinforcing fiber substrate (A')
is a unidirectionally arranged substrate. "Opening" refers to an
operation for separating a bundled reinforcing fiber bundle, which
can further enhance the impregnation properties of the poly
(phenylene ether ether ketone) oligomer (B). The opening reduces
the thickness of the reinforcing fiber substrate (A'), and the
opening ratio (w.sub.2/t.sub.2)/(w.sub.1/t.sub.1) is preferably 2.0
or more, and more preferably 2.5 or more, wherein w.sub.1 is the
width (mm) and t.sub.1 is the thickness (.mu.m) of a reinforcing
fiber bundle before opening, and w.sub.2 is the width (mm) and
t.sub.2 is the thickness (.mu.m) of the reinforcing fiber bundle
after opening.
[0240] Examples of the method for opening the reinforcing fiber
substrate (A') that can be used include, but are not limited to,
passing the reinforcing fiber substrate (A') alternately through a
concave roll and a convex roll, using a drum-type roll, applying
tension fluctuation to an axial oscillation, fluctuating the
tension of the reinforcing fiber substrate (A') using two friction
bodies that vertically reciprocate, and blowing air to the
reinforcing fiber substrate (A').
<Step [II]>
[0241] The step [II] is a step of combining the reinforcing fiber
substrate (A') with a poly (phenylene ether ether ketone) oligomer
(B). The method for combination is not particularly limited, and in
accordance with the form of the poly (phenylene ether ether ketone)
oligomer (B), the following three methods [C1] to [C3] are
preferred, for example.
[0242] [C1] A method for combination by applying a poly (phenylene
ether ether ketone) oligomer (B) in at least one form selected from
the group consisting of particles, fibers, and flakes to a
reinforcing fiber substrate (A'). When combination is performed by
this method, the poly (phenylene ether ether ketone) oligomer (B)
is preferably dispersed in a gas phase or liquid phase.
[0243] The method using a poly (phenylene ether ether ketone)
oligomer (B) dispersed in a gas phase is, in other words, a method
in which a poly (phenylene ether ether ketone) oligomer (B) in at
least one form selected from the group consisting of particles,
fibers, and flakes is scattered into a gas phase, and a reinforcing
fiber substrate (A') is passed through the gas phase. Specific
examples thereof include passing a reinforcing fiber substrate (A')
through a poly (phenylene ether ether ketone) oligomer (B)
scattered, for example, in a fluidized bed, scattering a poly
(phenylene ether ether ketone) oligomer (B) directly on a
reinforcing fiber substrate (A'), and charging a poly (phenylene
ether ether ketone) oligomer (B) to electrostatically attach to a
reinforcing fiber substrate (A').
[0244] The method using a poly (phenylene ether ether ketone)
oligomer (B) dispersed in a liquid phase is, in other words, a
method in which a poly (phenylene ether ether ketone) oligomer (B)
in at least one form selected from the group consisting of
particles, fibers, and flakes is dispersed or dissolved in a liquid
phase, and a reinforcing fiber substrate (A') is passed through the
liquid phase. "Dispersed (dispersing)" means that the poly
(phenylene ether ether ketone) oligomer (B) will not form a
macroaggregate of 1 mm or larger via reaggregation and maintains
its size in a preferred range in each form mentioned below.
Examples of such methods for dispersing or dissolving a poly
(phenylene ether ether ketone) oligomer (B) in a liquid phase
include, but are not limited to, a method using a stirring
apparatus, a method using a vibratory apparatus, a method using an
ultrasonic generator, and a method using a jet apparatus. To
maintain the dispersed state or dissolved state, it is more
preferable to use these methods also in the liquid phase through
which the reinforcing fiber substrate (A') is passed.
[0245] Examples of the liquid phase used here include water and
organic solvents, and using pure water or industrial water is more
preferred from the standpoint of economic efficiency and
productivity. To aid dispersion of the poly (phenylene ether ether
ketone) oligomer (B), various surfactants such as anionic,
cationic, and nonionic surfactants may be used in combination. The
amount of surfactant used is not critical, but it is preferably in
the range of 0.01 to 5 wt %, for example.
[0246] In the method for combination using a liquid phase, a
particularly preferred form of the poly (phenylene ether ether
ketone) oligomer (B) is an emulsion or dispersion. In this case,
from the standpoint of dispersibility, the average particle size is
preferably 0.01 to 100 .mu.m, more preferably 0.05 to 50 .mu.m, and
still more preferably 0.1 to 20 .mu.m.
[0247] When the poly (phenylene ether ether ketone) oligomer (B) is
particulate, the average particle size is preferably 50 to 300
.mu.m, more preferably 80 to 250 .mu.m, and still more preferably
100 to 200 .mu.m from the standpoint of processability and
handleability of particles. When the poly (phenylene ether ether
ketone) oligomer (B) is fibrous, the average fiber diameter is
preferably 0.5 to 50 .mu.m, more preferably 1 to 30 .mu.m, and
still more preferably 5 to 20 .mu.m for the same reason. The
average fiber length is not critical, but it is preferably in the
range of 1 to 10 mm, for example. When the poly (phenylene ether
ether ketone) oligomer (B) is flaky, it preferably has the same
thickness as in the case of particles and a length 5 to 100 times
the thickness.
[0248] The average particle size can be measured using, for
example, a laser diffraction/scattering-type particle size
distribution analyzer. The average fiber diameter, the average
fiber length, and the thickness and length of flakes can be
measured using a light microscope. When measuring the average fiber
diameter, the average fiber length, and the thickness and length of
flakes using a light microscope, the average value of the
measurements at randomly selected 400 points observed at 20 to
100.times. magnification may be used.
[0249] When an organic solvent is used as a liquid phase, any
solvent may be used as long as it does not substantially cause
undesirable side reactions such as inhibition of polymerization due
to heating of the poly (phenylene ether ether ketone) oligomer (B)
and decomposition or crosslinking of the poly (phenylene ether
ether ketone) (B') formed. Examples thereof include
N-methyl-2-pyrrolidone, dimethylformamide, dimethyl sulfoxide,
acetone, methyl ethyl ketone, diethyl ketone, dimethyl ether,
dipropyl ether, tetrahydrofuran, chloroform, methylene chloride,
trichloroethylene, ethylene dichloride, dichloroethane,
tetrachloroethane, chlorobenzene, methanol, ethanol, propanol,
butanol, pentanol, ethylene glycol, propylene glycol, phenol,
cresol, polyethylene glycol, benzene, toluene, and xylenes.
Inorganic compounds such as carbon dioxide, nitrogen, and water can
also be used as a solvent in the form of supercritical fluid. These
solvents can be used alone or in combination of two or more
thereof.
[0250] Examples of specific methods include feeding an emulsion or
dispersion of a poly (phenylene ether ether ketone) oligomer (B)
into a water tank and passing a reinforcing fiber substrate (A')
through the water tank, further passing the reinforcing fiber
substrate (A') through the water tank with the use of a jet flow,
and spraying an emulsion or dispersion of a poly (phenylene ether
ether ketone) oligomer (B) directly on a reinforcing fiber
substrate (A').
[0251] Further, in the method for combination using a liquid phase,
the water or organic solvent used is more preferably removed
(deliquored) after the passage through the reinforcing fiber
substrate (A') in terms of productivity. Examples of the removal
method include air blowing, hot air drying, and suction filtration.
In such a case, the rate of deliquoring the water or organic
solvent from the composite is not critical, but it is preferably 50
to 100%, more preferably 70 to 100%, and still more preferably 90
to 100%. Further, the liquid phase after deliquoring is
particularly preferably recovered, circulated, and reused in terms
of productivity and environment. The deliquoring rate can be
readily determined from the difference in composite mass before and
after deliquoring operation.
[0252] [C2] A method for combination by applying a poly (phenylene
ether ether ketone) oligomer (B) in at least one form selected from
the group consisting of a film, a sheet, and a nonwoven fabric to a
reinforcing fiber substrate (A'). "Film" as used herein refers to a
poly (phenylene ether ether ketone) oligomer (B) having an average
thickness of not more than 200 .mu.m, and "sheet" refers to one
having an average thickness of more than 200 .mu.m. "Nonwoven
fabric" refers to one in the form of a fiber sheet or web in which
fibers are unidirectionally or randomly oriented, and the fibers
are bonded together via interlacing, fusion, or adhesion. The
average thickness can be determined in such a manner that a
plurality of sheets or films is laminated; measurements are made
using calipers at randomly selected 10 points; and the thickness
obtained is divided by the number of lamination.
[0253] Examples of specific methods include transferring a
reinforcing fiber substrate (A') to a conveyor and laminating a
poly (phenylene ether ether ketone) oligomer(s) (B) in the form of
a film on one or both surfaces of the reinforcing fiber substrate
(A') using a hot roller, fixing a poly (phenylene ether ether
ketone) oligomer (B) in the form of a nonwoven fabric by punching,
and entangling a reinforcing fiber substrate (A') with a poly
(phenylene ether ether ketone) oligomer (B) in the form of a
nonwoven fabric using an air jet.
[0254] From the standpoint of economic efficiency and productivity,
the poly (phenylene ether ether ketone) oligomer (B) in any form of
a film, a sheet, and a nonwoven fabric is preferably rolled. When
it is difficult to roll the poly (phenylene ether ether ketone)
oligomer (B) alone, one preferred method is processing the poly
(phenylene ether ether ketone) oligomer (B) into a relevant form,
and then applying it on release paper for rolling.
[0255] [C3] A method for combination by applying a heat-melted poly
(phenylene ether ether ketone) oligomer (B) to a reinforcing fiber
substrate (A'). In the heat-melting here, an apparatus such as an
extruder or a molten bath can be used, which apparatus preferably
has a function to transfer the melted poly (phenylene ether ether
ketone) oligomer (B), such as a screw, a gear pump, or a
plunger.
[0256] Examples of specific methods include feeding a poly
(phenylene ether ether ketone) oligomer (B) to a mold die such as a
T-die or a slit die while melting it using an extruder and passing
a reinforcing fiber substrate (A') through the mold die, feeding a
poly (phenylene ether ether ketone) oligomer (B) to a molten bath
with a gear pump and passing a reinforcing fiber substrate (A')
through the molten bath with drawing, feeding a melted poly
(phenylene ether ether ketone) oligomer (B) to a kiss coater with a
plunger pump and applying the melt of the poly (phenylene ether
ether ketone) oligomer (B) to a reinforcing fiber substrate (A'),
and feeding a melted poly (phenylene ether ether ketone) oligomer
(B) onto a heated rotating roll and passing a reinforcing fiber
substrate (A') over the roll surface.
[0257] In the step of melting the poly (phenylene ether ether
ketone) oligomer (B), it is preferable to set the temperature such
that thermal polymerization of the poly (phenylene ether ether
ketone) oligomer (B) occurs as little as possible. The temperature
in the step of producing a molten mixture and the step of
impregnating the molten mixture is 160 to 340.degree. C.,
preferably 180 to 320.degree. C., more preferably 200 to
300.degree. C., and particularly preferably 230 to 270.degree. C.
When the temperature is in this preferred range, the poly
(phenylene ether ether ketone) oligomer (B) can be melted in a
short time, and at the same time, viscosity increase due to
formation of poly (phenylene ether ether ketone)s (B') is unlikely
to occur.
[0258] Further, the step [II] preferably comprises heating a
composite of a reinforcing fiber substrate (A') and a poly
(phenylene ether ether ketone) oligomer (B) to 160 to 340.degree.
C., preferably 180 to 320.degree. C., more preferably 200 to
300.degree. C., and particularly preferably 230 to 270.degree. C.
Through this heating, the poly (phenylene ether ether ketone)
oligomer (B) softens or melts and can be fixed more firmly to the
reinforcing fiber substrate (A'), which is advantageous for
increasing productivity. When the heating temperature is in this
preferred range, the poly (phenylene ether ether ketone) oligomer
(B) can be melted in a short time, and at the same time, viscosity
increase due to formation of poly (phenylene ether ether ketone)s
(B') is unlikely to occur.
[0259] Further, applying pressure simultaneously with or
immediately after the heating promotes impregnation of the poly
(phenylene ether ether ketone) oligomer (B) into the reinforcing
fiber substrate (A'), which is particularly preferred. The pressure
in this case is preferably 0.1 to 5 MPa, more preferably 0.3 to 4
MPa, and still more preferably 0.5 to 3 MPa from the standpoint of
productivity.
[0260] Examples of specific methods include passing a composite
through a heated chamber in which a plurality of pressure rollers
is provided, passing a composite through a heated chamber in which
calender rolls are provided one above the other, and simultaneously
performing heating and pressurization using a hot roller.
[0261] When a polymerization catalyst (D) is used, the
polymerization catalyst (D) is preferably added in the step [II]
from the standpoint of dispersibility in a poly (phenylene ether
ether ketone) oligomer (B). In this case, a mixture of a poly
(phenylene ether ether ketone) oligomer (B) and a polymerization
catalyst (D) may be used as processed into the form of particles,
fibers, flakes, a film, a sheet, a nonwoven fabric, or a heated
melt described above.
[0262] The mixture of a poly (phenylene ether ether ketone)
oligomer (B) and a polymerization catalyst (D) may be obtained by
any method, but it is preferable to add the polymerization catalyst
(D) to the poly (phenylene ether ether ketone) oligomer (B) and
then disperse the polymerization catalyst (D) uniformly. Examples
of the method for uniform dispersion include mechanical dispersion.
Specific examples of the mechanical dispersion include methods
using a grinder, stirrer, mixer, shaker, or mortar. In dispersing
the polymerization catalyst (D), the polymerization catalyst (D)
preferably has an average particle size of 1 mm or smaller to allow
more uniform dispersion.
<Step [III]>
[0263] The step [III] is a step of heating the composite of a
reinforcing fiber substrate (A') and a poly (phenylene ether ether
ketone) oligomer (B) obtained in the step [II] to polymerize the
poly (phenylene ether ether ketone) oligomer (B) into a poly
(phenylene ether ether ketone) (B'). The poly (phenylene ether
ether ketone) oligomer (B) is particularly preferably thermally
polymerized in the presence of the polymerization catalyst (D) to
convert into a poly (phenylene ether ether ketone) (B').
[0264] The lower limit of the temperature during thermal
polymerization is, for example, not lower than 160.degree. C.,
preferably not lower than 200.degree. C., more preferably not lower
than 230.degree. C., and still more preferably not lower than
270.degree. C. In this temperature range, it is likely that the
poly (phenylene ether ether ketone) oligomer (B) will melt and a
poly (phenylene ether ether ketone) (B') can be obtained in a short
time.
[0265] The upper limit of the temperature during thermal
polymerization is, for example, not higher than 450.degree. C.,
preferably not higher than 400.degree. C., more preferably not
higher than 350.degree. C., and still more preferably not higher
than 300.degree. C. When the heating temperature is not higher than
this temperature range, it is likely that adverse effects of
undesirable side reactions on the properties of the poly (phenylene
ether ether ketone) (B') can be prevented.
[0266] Further, the poly (phenylene ether ether ketone) oligomer
(B) in the present invention can also be polymerized at a
temperature not higher than the melting point of the poly
(phenylene ether ether ketone) (B') obtained by polymerization. In
such a temperature range, the poly (phenylene ether ether ketone)
oligomer (B) undergoes crystallization polymerization, which
results in a molding material comprising as a matrix resin a poly
(phenylene ether ether ketone) (B') with crystallinity higher than
usual and, in turn, melting enthalpy higher than usual.
[0267] The reaction time until completion of the polymerization in
the step [III] is preferably as short as possible because
productivity and economic efficiency increase: e.g., process length
can be shortened, or take-up speed can be increased. The reaction
time is preferably 60 minutes or less, and more preferably 10
minutes or less, for example. The lower limit of the reaction time
is not particularly limited, but it is not less than 0.05 minutes,
for example.
[0268] In the polymerization of the poly (phenylene ether ether
ketone) oligomer (B) in the step [III], heating is preferably
performed in a non-oxidizing atmosphere in order to inhibit the
occurrence of undesirable side reactions such as cross-linking
reaction and decomposition reaction. Here, "non-oxidizing
atmosphere" refers to an atmosphere with an oxygen concentration of
5% by volume or less, preferably 2% by volume or less, and more
preferably free of oxygen, i.e., an atmosphere of inert gas such as
nitrogen, helium, and argon. Among them, a nitrogen atmosphere is
preferred particularly in terms of economic efficiency and
handleability.
[0269] Also in the step [III], heating is preferably performed
under reduced pressure. In this case, it is more preferred that the
atmosphere in the reaction system be once replaced with a
non-oxidizing atmosphere before adjusting to reduced-pressure
conditions. "Under reduced pressure" as used herein refers to a
condition where the pressure in the reaction system is lower than
atmospheric pressure, and the pressure is preferably 0.1 to 50 kPa,
more preferably 0.1 to 10 kPa.
[0270] Further, the step [III] preferably comprises applying
pressure simultaneously with or after heating. It is preferred
because impregnation of the reinforcing fiber substrate (A') with a
poly (phenylene ether ether ketone) oligomer (B) and a poly
(phenylene ether ether ketone) (B') can be further improved. The
pressure in this case is preferably 0.1 to 10 MPa, more preferably
0.2 to 5 MPa, and still more preferably 2 to 6 MPa from the
standpoint of the balance between impregnation properties and
productivity. When the pressure is in this preferred range, voids
will not occur in a large amount in the molding material and, in
turn, in the resulting molded article, and at the same time, the
arrangement of the reinforcing fiber substrate (A') will not be
greatly disarranged.
[0271] Examples of specific methods include passing a composite
through a nitrogen-substituted system while applying pressure from
above and beneath with a double belt press; passing a composite
through a plurality of calender rolls while applying pressure in a
nitrogen-substituted heating furnace; and placing a composite
between press molds at high temperature, sealing the space between
the press molds, substituting the atmosphere in the molds with
nitrogen upon pressurization, and opening the press molds after
completion of polymerization under reduced-pressure conditions to
pull out the composite. To improve impregnation properties, these
apparatuses may be used in combination; the line may be wound in
order to increase the length; or the composite that has passed
through the apparatus may be repeatedly used to loop through the
same apparatus more than once.
<Step [IV]>
[0272] The step [IV] is a step of cooling and taking up the
composite obtained in the step [III]. Examples of the method for
cooling that can be used include, but are not limited to, cooling
by blowing air, spraying cooling water, passing through a cooling
bath, and passing over a cooling plate.
[0273] When the molding material is produced on-line, the take-up
speed is preferably as high as possible because it directly
influences economic efficiency and productivity. The take-up speed
is preferably 1 to 100 m/min, more preferably 5 to 100 m/min, and
still more preferably 10 to 100 m/min.
[0274] Examples of specific methods include drawing with a nip
roller, taking up with a drum winder, and gripping a substrate with
a fixture and taking up the substrate together with the fixture.
When taking up a substrate, the substrate may be cut partially with
a slitter, may be processed into a sheet of a given length with a
guillotine cutter or the like, may be cut to a certain length with
a strand cutter or the like, or may be kept in the form of a
roll.
[0275] The method for producing a molding material of the present
invention can comprise other processes as long as the effects of
the present invention are not inhibited. Examples of the process
include electron beam irradiation, plasma treatment, strong
magnetic field application, surface material lamination, protective
film application, and after curing.
[0276] The molding material obtained by the method for producing a
molding material of the present invention comprises a reinforcing
fiber substrate (A') and a poly (phenylene ether ether ketone)
oligomer (B).
[0277] Among them, the content of the reinforcing fiber substrate
(A') is preferably 10 wt % or more, more preferably 30 wt % or
more, still more preferably 60 wt % or more, and particularly
preferably 70 wt % or more, based on 100 wt % of the total of the
reinforcing fiber substrate (A') and the poly (phenylene ether
ether ketone) oligomer (B). When the content of the reinforcing
fiber substrate (A') is less than 10 wt %, the resulting molded
article may have poor dynamic properties. The upper limit of the
content of the reinforcing fiber substrate (A') is not limited, but
it is preferably not more than 90 wt %, more preferably not more
than 80 wt %, and still more preferably not more than 70 wt %. When
the content of the reinforcing fiber substrate (A') is more than 90
wt %, it can be difficult to impregnate the poly (phenylene ether
ether ketone) oligomer (B) into the reinforcing fiber substrate
(A'). The content of the reinforcing fiber substrate (A') in the
molding material of the present invention can be adjusted by
controlling the supply of the reinforcing fiber substrate (A') and
the poly (phenylene ether ether ketone) oligomer (B).
[0278] Further, when a polymerization catalyst (D) is contained,
the content thereof is 0.001 to 20 mol %, preferably 0.005 to 15
mol %, and more preferably 0.01 to 10 mol %, based on 1 mol of the
repeating unit represented by the following formula, which is a
main structural unit of the poly (phenylene ether ether ketone)
oligomer (B).
##STR00007##
[0279] Such percentages can be readily achieved by controlling the
supply of the reinforcing fiber substrate (A') and the poly
(phenylene ether ether ketone) oligomer (B). For example, the
supply of the reinforcing fiber substrate (A') can be controlled by
the take-up speed in the step [IV], and the supply of the poly
(phenylene ether ether ketone) oligomer (B) can be controlled in
the step [II] using a metering feeder or the like. For the supply
of the polymerization catalyst (D), the amount in the molding
material can be controlled by controlling the amount added to the
poly (phenylene ether ether ketone) oligomer (B).
[0280] Further, according to the production method of the present
invention, molding materials having different impregnation rates
can be produced depending on the application and purpose of the
molding material. Examples thereof include a prepreg with higher
impregnation properties, a semi-impregnated semipreg, and a fabric
with low impregnation properties. In general, a molding material
with higher impregnation properties tends to provide a molded
article having excellent dynamic properties by molding in a shorter
time. In contrast, a molding material with relatively low
impregnation properties tends to be excellent in drape property and
shaping into, for example, a curved shape.
[0281] Thus, in the molding material obtained according to the
present invention, a first preferred aspect of the impregnation
rate of the poly (phenylene ether ether ketone) (B') is a molding
material having an impregnation rate of 80% to 100%. This is
advantageous in terms of production of a molded article of simpler
planar shape with high productivity.
[0282] Further, in the molding material obtained according to the
present invention, a second preferred aspect of the impregnation
rate of the poly (phenylene ether ether ketone) (B') is a molding
material having an impregnation rate of 20% to less than 80%. This
is a molding material having excellent drape property, and the
molding material can be shaped in advance to a mold, which is
advantageous in terms of production of a molded article of
relatively complex shape such as curved shape with high
productivity.
[0283] "Impregnation rate of the poly (phenylene ether ether
ketone) (B')" as used herein is expressed as a percentage (%)
obtained by observing a cross-section of the molding material using
a light microscope and dividing the area of impregnation of the
poly (phenylene ether ether ketone) (B') by the total of such area
and the area of voids.
[0284] When measuring the areas using a light microscope, the
average value of the measurements of randomly selected 20 images
observed at 20 to 100.times. magnification may be used.
[0285] Examples of means for controlling the impregnation rate
include temperature and pressure in combining the poly (phenylene
ether ether ketone) oligomer (B) in the step [II], and temperature
and pressure in polymerizing the poly (phenylene ether ether
ketone) oligomer (B) into a poly (phenylene ether ether ketone)
(B') in the step [III]. In general, the higher the temperature and
the pressure are, the greater the effect of increasing the
impregnation rate is. The finer the form of the poly (phenylene
ether ether ketone) oligomer (B) is, the more the impregnation
properties can be enhanced.
<Method for Molding Molding Material>
[0286] The molding material obtained by the present invention can
be molded into a molded article in such a manner that at least one
layer of the molding material is laminated in any configuration and
then molded while applying heat and pressure.
[0287] Examples of methods of applying heat and pressure that can
be used include the press molding method in which the molding
material laminated in any configuration is placed in a mold or on a
pressing plate, and then the mold or the pressing plate is closed
and pressurized; the autoclave molding method in which the molding
material laminated in any configuration is charged into an
autoclave, and pressurized and heated; the bag-molding method in
which the molding material laminated in any configuration is
wrapped with a film or the like and, with the internal pressure
reduced, heated in an oven while being pressurized at atmospheric
pressure; the wrapping tape method in which the molding material
laminated in any configuration is wrapped with tape under tension
and heated in an oven; and the internal pressure molding method in
which the molding material laminated in any configuration is placed
in a mold, and a core that is also placed in the mold is charged
with gas or liquid and pressurized. In particular, molding methods
in which pressing is performed using a mold are preferred because a
molded article with low void and excellent appearance quality can
be obtained.
[0288] The heating temperature during molding is, for example, in
the range of 160 to 450.degree. C., more preferably 230 to
430.degree. C., and still more preferably 270 to 400.degree. C.
When the heating temperature during molding in this preferred
range, the poly (phenylene ether ether ketone) (B') easily melts,
and at the same time, the poly (phenylene ether ether ketone) (B')
is unlikely to be thermally degraded.
[0289] Examples of the method here for measuring the heating
temperature during molding include, in the case of a molding method
in which molding is performed using a mold, measuring the surface
temperature of the mold using a thermometer such as a
thermocouple.
[0290] The pressure during molding is preferably in the range of
0.1 to 10 MPa, and more preferably in the range of 0.2 to 5 MPa,
for example. When the pressure during molding is in this preferred
range, voids will not occur in a large amount in the molding
material and, in turn, in the resulting molded article, and at the
same time, the arrangement of the reinforcing fiber substrate (A')
will not be greatly disarranged.
[0291] Time for performing hot-pressing during molding is not
critical, but it is in the range of 0.001 to 1,000 minutes,
preferably 0.01 to 300 minutes, more preferably 0.1 to 60 minutes,
still more preferably 0.3 to 30 minutes, and particularly
preferably 0.5 to 10 minutes. When the impregnation time is in this
preferred range, the poly (phenylene ether ether ketone) (B') melts
sufficiently, and at the same time, the molding material can be
produced efficiently.
[0292] The molding material obtained by the present invention can
be easily molded also by integrally molding such as insert molding
or outsert molding. Further, highly productive adhesion techniques
can be employed after molding, such as reformation by heating, heat
welding, vibration welding, and ultrasonic welding.
<Molded Article>
[0293] The molded article using the molding material obtained by
the present invention is excellent in heat resistance, mechanical
properties, flame resistance, chemical resistance, and the like.
Further, since the matrix resin in the molded article is a
thermoplastic resin, the resin can be plasticized, for example, by
heating, and thus the molded article can be easily recycled or
repaired. Examples of the molded article include industrial machine
parts (e.g., automotive parts such as thrust washers, oil filters,
seals, bearings, gears, cylinder head covers, bearing retainers,
intake manifolds, and pedals; semiconductor/liquid crystal
manufacturing equipment parts such as silicon wafer carriers, IC
chip trays, electrolytic capacitor trays, and insulating films;
compressor parts such as pumps, valves, and seals; and aircraft
cabin interior parts); medical equipment parts such as
sterilization devices, columns, and tubes; and food/beverage
production equipment parts. Further, since the molding material of
the present invention has excellent fluidity, a thin-walled molded
article with a thickness of 0.5 to 2 mm can be obtained with
relative ease. Examples of products that require such thin-wall
molding include housings used for personal computers, cellular
phones, and the like, and members for electrical and electronic
equipment as typified by a keyboard support which is a member for
supporting a keyboard inside a personal computer. In such members
for electrical and electronic equipment, electromagnetic shielding
properties are provided when a conductive carbon fiber is used as a
reinforcing fiber, which is more preferred.
<First Method for Producing Fiber-Reinforced Composite
Material>
[0294] The first method for producing a fiber-reinforced composite
material of the present invention is Resin Transfer Molding method
(RTM), comprising the steps of (I-1) placing a reinforcing fiber
substrate (A') in a mold, (II-1) heat-melting a poly (phenylene
ether ether ketone) oligomer (B) to form a melt solution, (III-1)
injecting the melt solution obtained in the step (II-1) into the
mold of the step (I-1) to impregnate the component (B) into the
component (A'), and (IV-1) thermally polymerizing the component (B)
into a poly (phenylene ether ether ketone) (B'), wherein the poly
(phenylene ether ether ketone) oligomer (B) used in step (II-1) has
a melting point of not higher than 270.degree. C.
[0295] The step (I-1) is a step of placing a reinforcing fiber
substrate (A') in a mold. The mold used is preferably a rigid
closed mold. Various existing materials such as metals (e.g.,
steel, aluminum, and INVAR) and fiber-reinforced composite
materials are used as materials for the mold.
[0296] From the standpoint of shapability, the reinforcing fiber
substrate (A') preferably used is a fabric (cloth), nonwoven
fabric, mat, or knit. The shape of the reinforcing fiber substrate
(A') may be planar or irregular. These shapes may be used alone or
arranged in combination. In particular, when an irregular
fiber-reinforced composite material is desired, preforms obtained
by shaping a reinforcing fiber substrate (A') to the design surface
of a mold are preferably used.
[0297] The step (II-1) is a step of heat-melting a poly (phenylene
ether ether ketone) oligomer (B) to form a melt solution. In the
heat-melting here, an apparatus such as a molten bath can be used,
which apparatus preferably has a function to transfer the melted
poly (phenylene ether ether ketone) oligomer (B), such as a screw,
a gear pump, or a plunger.
[0298] The step (III-1) is a step of injecting the melt solution
obtained in the step (II-1) into the mold of the step (I-1) to
impregnate the poly (phenylene ether ether ketone) oligomer (B)
into the reinforcing fiber substrate (A').
[0299] When a rigid closed mold is used, into a mold clamped by
pressurization, a melt solution of poly (phenylene ether ether
ketone) oligomer (B) is generally injected while applying pressure.
In this case, in addition to an injection port, a suction port may
be provided to suck the melt solution by means of a vacuum pump or
the like. It is also possible to inject the solution of poly
(phenylene ether ether ketone) oligomer (B) only by means of
atmospheric pressure by suction without using particular
pressurizing means.
[0300] The step (IV-1) is a step of thermally polymerizing the poly
(phenylene ether ether ketone) oligomer (B) into a poly (phenylene
ether ether ketone) (B').
[0301] The temperature during thermal polymerization preferably
used is a temperature of the polymerization of the poly (phenylene
ether ether ketone) oligomer (B) into a poly (phenylene ether ether
ketone) (B') described above. In particular, conditions under which
the crystallization polymerization described above occurs are
preferably used because the process for cooling a mold can be
shortened when demolding a molded article after polymerization.
Examples of the method here for measuring the heating temperature
include measuring the surface temperature of the mold using a
thermometer such as a thermocouple.
[0302] The reaction time until completion of polymerization in the
step (IV-1) is preferably as short as possible because productivity
and economic efficiency increase. The reaction time is preferably
60 minutes or less, and more preferably 10 minutes or less, for
example. The lower limit of the reaction time is not particularly
limited, but it is not less than 0.05 minutes, for example.
[0303] It should be noted that the above description is an example
of RTM methods, and the method for producing a fiber-reinforced
composite material of the present invention is not limited
thereto.
[0304] Further, in the first method for producing a
fiber-reinforced composite material of the present invention, in
addition to the reinforcing fiber substrate (A'), a foam core, a
honeycomb core, metal parts, or the like can be placed in a mold to
provide a fiber-reinforced composite material integrated therewith.
In particular, a sandwich structure obtained by placing reinforcing
fiber substrates (A') on both surfaces of a foam core or honeycomb
core followed by molding is useful because it is lightweight and
has excellent flexural rigidity.
[0305] Further, prior to placing a reinforcing fiber substrate (A')
in a mold, a gelcoat can be applied to the surface of the mold.
<Second Method for Producing Fiber-Reinforced Composite
Material>
[0306] The second method for producing a fiber-reinforced composite
material of the present invention is a so-called filament winding
molding method, comprising the steps of (I-2) drawing and
continuously feeding a reinforcing fiber substrate (A'), (II-2)
heat-melting a poly (phenylene ether ether ketone) oligomer (B) in
an impregnation bath to form a melt solution, (III-2) passing the
component (A') continuously through the impregnation bath of the
step (II-2) to impregnate the component (B) into the component (A')
and winding the resulting composite around a mandrel, and (IV-2)
thermally polymerizing the component (B) into a poly (phenylene
ether ether ketone) (B'), wherein the poly (phenylene ether ether
ketone) (B) has a melting point of not higher than 270.degree.
C.
[0307] The step (I-2) is a step of drawing and continuously feeding
a reinforcing fiber substrate (A'). "Continuous" means that the
reinforcing fiber substrate (A') which is a raw material is fed
unceasingly without a complete break. The feed rate may be
constant, or feeding and cessation may be repeated
intermittently.
[0308] From the standpoint of productivity, the reinforcing fiber
substrate (A') preferably used is a reinforcing fiber bundle.
Further, the reinforcing fiber substrate (A') is more preferably
opened before feeding. "Opening" as used herein refers to an
operation for separating a bundled reinforcing fiber substrate
(A'), which can further enhance the impregnation properties of a
poly (phenylene ether ether ketone) oligomer (B). Examples of the
method for opening the reinforcing fiber substrate (A') that can be
used include, but are not limited to, passing the reinforcing fiber
substrate (A') alternately through a concave roll and a convex
roll, using a drum-type roll, applying tension fluctuation to an
axial oscillation, fluctuating the tension of the reinforcing fiber
substrate (A') using two friction bodies that vertically
reciprocate, and blowing air to the reinforcing fiber substrate
(A').
[0309] The step (II-2) is a step of heat-melting a poly (phenylene
ether ether ketone) oligomer (B) in an impregnation bath to form a
melt solution. The impregnation bath in this step is preferably
equipped with a heating source for heat-melting the poly (phenylene
ether ether ketone) oligomer (B) to form a melt solution and
further storing the melt solution for a predetermined time, and is
preferably equipped with a mechanism by which the reinforcing fiber
substrate (A') is continuously immersed in the melt solution and
taken up.
[0310] The step (III-2) is a step of passing the reinforcing fiber
substrate (A') continuously through the impregnation bath of the
step (II-2) to impregnate the poly (phenylene ether ether ketone)
oligomer (B) into the reinforcing fiber substrate (A') and winding
the resulting composite around a mandrel. The composite obtained
here is wound spirally around the mandrel at various angles to its
axial direction. A surface material or the like may then be wound
tightly around the surface to squeeze out excess resin.
[0311] The step (IV-2) is a step of thermally polymerizing the poly
(phenylene ether ether ketone) oligomer (B) into a poly (phenylene
ether ether ketone) (B'). An oven and the like can preferably be
used as a heating apparatus, and examples of preferred methods
include heating the mandrel around which the composite was wound in
the step (III-2) to polymerize the poly (phenylene ether ether
ketone) oligomer (B).
[0312] The temperature during thermal polymerization preferably
used is a temperature of the polymerization of the poly (phenylene
ether ether ketone) oligomer (B) into a poly (phenylene ether ether
ketone) (B') described above. Examples of the method here for
measuring the heating temperature include measuring the atmosphere
temperature in the oven using a thermometer such as a
thermocouple.
[0313] The reaction time until completion of polymerization in the
step (IV-2) is preferably as short as possible because productivity
and economic efficiency increase. The reaction time is preferably
60 minutes or less, and more preferably 10 minutes or less, for
example. The lower limit of the reaction time is not particularly
limited, but it is not less than 0.05 minutes, for example.
[0314] It should be noted that the above description is an example
of filament winding methods, and the method for producing a
fiber-reinforced composite material of the present invention is not
limited thereto.
[0315] According to the second method for producing a
fiber-reinforced composite material of the present invention, a
cylindrical fiber-reinforced composite material can be readily
obtained. Thus, the method is suitable for various industrial
machine parts such as automotive propeller shafts, CNG tanks, and
flywheels; and sports/leisure goods such as golf shafts and fishing
rods.
<Third Method for Producing Fiber-Reinforced Composite
Material>
[0316] The third method for producing a fiber-reinforced composite
material of the present invention is a so-called pultrusion molding
method, comprising the steps of (I-3) drawing and continuously
feeding a reinforcing fiber substrate (A'), (II-3) heat-melting a
poly (phenylene ether ether ketone) oligomer (B) in an impregnation
bath to form a melt solution, (III-3) passing the component (A')
continuously through the impregnation bath of the step (II-3) to
form a composite of the component (B) and the component (A')
impregnated therewith, and (IV-3) pultruding the composite obtained
continuously through a mold to thermally polymerize the component
(B) into a poly (phenylene ether ether ketone) (B'), wherein the
poly (phenylene ether ether ketone) (B) has a melting point of not
higher than 270.degree. C.
[0317] The step (I-3) is a step of drawing and continuously feeding
a reinforcing fiber substrate (A'). "Continuous" means that the
reinforcing fiber substrate (A') which is a raw material is fed
unceasingly without a complete break. The feed rate may be
constant, or feeding and cessation may be repeated
intermittently.
[0318] From the standpoint of productivity, the reinforcing fiber
substrate (A') preferably used is a unidirectionally arranged
substrate. Specifically, for example, a method is preferably used
in which a plurality of reinforcing fiber bundles is
unidirectionally arranged in the form of a sheet, further passed
through a roll bar, and fed to a production line.
[0319] Further, the reinforcing fiber substrate (A') is more
preferably opened before feeding. "Opening" as used herein refers
to an operation for separating a bundled reinforcing fiber
substrate (A'), which can further enhance the impregnation
properties of a poly (phenylene ether ether ketone) oligomer (B).
Examples of the method for opening the reinforcing fiber substrate
(A') that can be used include, but are not limited to, passing the
reinforcing fiber substrate (A') alternately through a concave roll
and a convex roll, using a drum-type roll, applying tension
fluctuation to an axial oscillation, fluctuating the tension of the
reinforcing fiber substrate (A') using two friction bodies that
vertically reciprocate, and blowing air to the reinforcing fiber
substrate (A').
[0320] The step (II-3) is a step of heat-melting a poly (phenylene
ether ether ketone) oligomer (B) in an impregnation bath to form a
melt solution. The impregnation bath in this step is preferably
equipped with a heating source for heat-melting the poly (phenylene
ether ether ketone) oligomer (B) to form a melt solution and
further storing the melt solution for a predetermined time, and is
preferably equipped with a mechanism by which the reinforcing fiber
substrate (A') is continuously immersed in the melt solution and
taken up.
[0321] The step (III-3) is a step of passing the reinforcing fiber
substrate (A') continuously through the impregnation bath of the
step (II-3) to form a composite of the poly (phenylene ether ether
ketone) oligomer (B) and the reinforcing fiber substrate (A')
impregnated therewith.
[0322] Further, the composite obtained in the step (II-3) may be
passed through a squeeze die before being passed through the mold
of the step (III-3). "Squeeze die" as used herein refers to a
fixture for scraping excess melt solution from the reinforcing
fiber substrate (A') that has passed through the impregnation bath.
The squeeze die may be of any shape as long as excess melt solution
can be scraped off, and examples of the shape of the cross-section
taken perpendicular to the pultrusion direction include a circle,
rectangle, and square. The squeeze die may be of any material, and
preferred examples thereof include metals, plastics, and
ceramics.
[0323] The step (IV-3) is a step of pultruding the composite
obtained continuously through a mold to thermally polymerize the
poly (phenylene ether ether ketone) oligomer (B) into a poly
(phenylene ether ether ketone) (B').
[0324] The mold used in this step may be any mold as long as it has
a cross-sectional shape that corresponds to the shape of the final
fiber-reinforced composite material of interest, and examples of
the cross-sectional shape include a circle, oval, rectangle,
square, L-shape, and U-shape. Examples of the material of the mold
include steel, aluminum, and INVAR.
[0325] The temperature during thermal polymerization preferably
used is a temperature of the polymerization of the poly (phenylene
ether ether ketone) oligomer (B) into a poly (phenylene ether ether
ketone) (B') described above. Examples of the method here for
measuring the heating temperature include measuring the surface
temperature of the mold using a thermometer such as a
thermocouple.
[0326] The reaction time until completion of polymerization in the
step (IV-3) is preferably as short as possible because productivity
and economic efficiency increase. The reaction time is preferably
60 minutes or less, and more preferably 10 minutes or less, for
example. The lower limit of the reaction time is not particularly
limited, but it is not less than 0.05 minutes, for example.
[0327] Examples of methods for pulling out the fiber-reinforced
composite material obtained in the present invention include, but
are not limited to, drawing with a nip roller or a belt conveyor
and taking up with a drum winder.
[0328] Prior to the pultrusion operation described above, the
fiber-reinforced composite material obtained is preferably cooled.
Examples of cooling methods include, but are not limited to,
passing in contact with a roller equipped with a cooling unit,
passing in contact with a cooling plate, and passing through a
cooling bath. In particular, the method of passing in contact with
a roller equipped with a cooling unit is preferably used because
pressure can be applied.
[0329] It should be noted that the above description is an example
of pultrusion molding methods, and the method for producing a
fiber-reinforced composite material of the present invention is not
limited thereto.
[0330] According to the third method for producing a
fiber-reinforced composite material of the present invention, a
long fiber-reinforced composite material can be readily obtained.
Thus, the fiber-reinforced composite material is suitably used as a
reinforcing material for buildings, vehicles, and aircrafts.
[0331] The method for producing a fiber-reinforced composite
material of the present invention can comprise other processes as
long as the effects of the present invention are not inhibited.
Examples of the process include electron beam irradiation, plasma
treatment, strong magnetic field application, surface material
lamination, protective film application, and after curing.
<Forming Melt Solution of Poly (Phenylene Ether Ether Ketone)
Oligomer (B)>
[0332] In the step (II-1), (II-2), or (II-3) in the method for
producing a fiber-reinforced composite material of the present
invention, the poly (phenylene ether ether ketone) oligomer (B)
needs to be formed into a melt solution by heat-melting. The
temperature for forming a melt solution by heat-melting is
preferably set at such a temperature that thermal polymerization of
the poly (phenylene ether ether ketone) oligomer (B) occurs as
little as possible. Such a temperature is, for example, in the
range of 160 to 340.degree. C., preferably 180 to 320.degree. C.,
more preferably 200 to 300.degree. C., and particularly preferably
230 to 270.degree. C. When the temperature is in this range, the
melt viscosity of the poly (phenylene ether ether ketone) oligomer
(B) can be adjusted to 10 Pas or lower, facilitating impregnation
into a reinforcing fiber substrate (A'). When the temperature is
this preferred in range, the poly (phenylene ether ether ketone)
oligomer (B) can be melted in a short time, and at the same time,
viscosity increase due to formation of poly (phenylene ether ether
ketone)s (B') is unlikely to occur.
<Fiber-Reinforced Composite Material>
[0333] The fiber-reinforced composite material obtained in the
present invention comprises a reinforcing fiber substrate (A') and
a poly (phenylene ether ether ketone) oligomer (B).
[0334] Among them, the content of the reinforcing fiber substrate
(A') is preferably 10 wt % or more, more preferably 30 wt % or
more, still more preferably 60 wt % or more, and particularly
preferably 70 wt % or more, based on 100 wt % of the total of the
reinforcing fiber substrate (A') and the poly (phenylene ether
ether ketone) oligomer (B). The upper limit of the content of the
reinforcing fiber substrate (A') is not limited, but it is
preferably not more than 90 wt %, more preferably not more than 80
wt %, and still more preferably not more than 70 wt %. When the
content of the reinforcing fiber substrate (A') in this preferred
range, the resulting molded article has sufficient dynamic
properties, and in addition, the poly (phenylene ether ether
ketone) oligomer (B) is easily impregnated into the reinforcing
fiber substrate (A'). The content of the reinforcing fiber
substrate (A') in the fiber-reinforced composite material obtained
according to the present invention can be adjusted by controlling
the supply of the reinforcing fiber substrate (A') and the poly
(phenylene ether ether ketone) oligomer (B).
[0335] Further, when a polymerization catalyst (D) is contained,
the content thereof is 0.001 to 20 mol %, preferably 0.005 to 15
mol %, and more preferably 0.01 to 10 mol %, based on 1 mol of the
repeating unit represented by the following formula, which is a
main structural unit of the poly (phenylene ether ether ketone)
oligomer (B).
##STR00008##
[0336] For the supply of the polymerization catalyst (D), the
amount in the fiber-reinforced composite material can be controlled
by controlling the amount added to the poly (phenylene ether ether
ketone) oligomer (B).
[0337] The fiber-reinforced composite material obtained in the
present invention is preferably has a small void fraction. A
preferred range of the void fraction is, for example, 0 to 20%.
When the void fraction is in such a range, a fiber-reinforced
composite material having excellent dynamic properties can be
obtained.
[0338] "Void fraction of the fiber-reinforced composite material"
as used herein is expressed as a percentage (%) obtained by
observing a cross-section of the fiber-reinforced composite
material using a light microscope and dividing the area of voids by
the total area observed.
[0339] When measuring the areas using a light microscope, the
average value of the measurements of randomly selected 20 images
observed at 20 to 100.times. magnification may be used.
[0340] In the step (IV-1), (IV-2), or (IV-3) in the method for
producing a fiber-reinforced composite material of the present
invention, performing polymerization reaction of the poly
(phenylene ether ether ketone) oligomer (B) into a poly (phenylene
ether ether ketone) (B') in a temperature range of 160 to
330.degree. C., preferably 200 to 300.degree. C., allows the
crystallization polymerization mentioned above to proceed.
Adjusting to such conditions is preferred in terms of productivity:
e.g., the process for cooling the fiber-reinforced composite
material can be shortened.
[0341] The fiber-reinforced composite material obtained in the
present invention can be used for integrally molding such as insert
molding or outsert molding. Further, highly productive adhesion
techniques can be employed, such as reformation by heating, heat
welding, vibration welding, and ultrasonic welding.
[0342] The fiber-reinforced composite material obtained in the
present invention is excellent in heat resistance, mechanical
properties, flame resistance, chemical resistance, and the like
because the matrix resin therein is a poly (phenylene ether ether
ketone). Further, since the matrix resin is a thermoplastic poly
(phenylene ether ether ketone), the resin can be plasticized, for
example, by heating, and thus the resulting molded article can be
easily recycled or repaired.
[0343] Examples of the application thereof include industrial
machine parts (e.g., automotive parts such as thrust washers, oil
filters, seals, bearings, gears, cylinder head covers, bearing
retainers, intake manifolds, and pedals; semiconductor/liquid
crystal manufacturing equipment parts such as silicon wafer
carriers, IC chip trays, electrolytic capacitor trays, and
insulating films; compressor parts such as pumps, valves, and
seals; and aircraft cabin interior parts); medical equipment parts
such as sterilization devices, columns, and tubes; and
food/beverage production equipment parts.
EXAMPLES
[0344] The present invention will now be described in more detail
by way of example.
[0345] Evaluation methods used in the present invention will be
described below.
(1) Quantification of Cyclic Poly (Phenylene Ether Ether
Ketone)
[0346] Cyclic poly (phenylene ether ether ketone)s in a poly
(phenylene ether ether ketone) oligomer (B) was quantified using
high-performance liquid chromatography. Measurement conditions will
be described below.
[0347] Apparatus: LC-10Avp Series manufactured by Shimadzu
Corporation Column: Mightysil RP-18GP150-4.6
[0348] Detector: Photodiode array detector (UV=270 nm)
[0349] Column temperature: 40.degree. C.
[0350] Sample: 0.1 wt % THF solution
[0351] Mobile phase: THF/0.1 w % aqueous trifluoroacetic acid
solution
(2) Differential Scanning Calorimeter
[0352] In accordance with JIS K 7121 (1987), measurements were made
using a differential scanning calorimeter, DSC system TA3000
(available from METTLER), at a temperature rise rate of 10.degree.
C./min. The melting peak temperature was employed as a melting
point, and a melting enthalpy was determined from the melting peak
area.
(3) Infrared Spectroscopy Analyzer
[0353] Absorption spectra were measured by infrared spectroscopy
under the following conditions.
[0354] Apparatus: Perkin Elmer System 2000 FT-IR
[0355] Sample preparation: KBr method
(4) Viscosity Measurement
[0356] Reduced viscosities were measured under the following
conditions.
[0357] Viscometer: Ostwald viscosimeter
[0358] Solvent: 98 wt % sulfuric acid
[0359] Sample concentration: 0.1 g/dL (sample weight/solvent
volume)
[0360] Measurement temperature: 25.degree. C.
[0361] Equation of reduced viscosity: .eta.={(t/t.sub.0)-1}/C
[0362] t: Transit time of sample solution in seconds
[0363] t.sub.0: Transit time of solvent in seconds
[0364] C: Concentration of solution
(5) Evaluation of Productivity of Molding Material
[0365] The shape of the molding material obtained was visually
observed to check for defective products (resin cracks, reinforcing
fiber dropout). From the molding material obtained, 20 g of samples
were randomly extracted. Using as a criterion a defective rate
which corresponds to the total number of defective products in the
samples, evaluation was carried out on the following 3-point scale,
and "good" and "fair" were evaluated as acceptable.
[0366] Good: The defective rate is less than 1/20 g. Productivity
of the molding material is particularly excellent.
[0367] Fair: The defective rate is 1/20 g to less than 5/20 g.
Productivity of the molding material is excellent.
[0368] Bad: The defective rate is not less than 5/20 g.
Productivity of the molding material is poor.
(6) Average Fiber Length of Reinforcing Fibers Contained in Molded
Article Obtained Using Molding Material
[0369] A portion of a molded article was cut out and hot-pressed at
400.degree. C. to obtain a 30-.mu.m-thick film. The film obtained
was observed under a light microscope at 150.times. magnification
to observe fibers dispersed in the film. The length of the fibers
was measured in micrometers, and the weight average fiber length
(Lw) and the number average fiber length (Ln) were determined by
the following equation.
Weight average fiber length (Lw)=.SIGMA.(Li.times.Wi/100)
Number average fiber length (Ln)=(.SIGMA.Li)/N.sub.total
[0370] Li: Measured fiber length (i=1, 2, 3, . . . , n)
[0371] Wi: Weight fraction of fibers with a fiber length of Li
(i=1, 2, 3, . . . , n)
[0372] N.sub.total: Total number of fibers subjected to fiber
length measurement
(7) Densitie of Molded Article Obtained Using Molding Material
[0373] Measurements were made in accordance with the method A
(water displacement method) described in JIS K 7112 (1999) 5. A
test piece of 1 cm.times.1 cm was cut out from a molded article and
loaded into a heat-resistant glass container. The container was
vacuum-dried at a temperature of 80.degree. C. for 12 hours, and
cooled to room temperature in a desiccator so that the test piece
does not absorb moisture. Ethanol was used as an immersion
liquid.
(8) Appearance Evaluation of Molded Article Obtained Using Molding
Material
[0374] The surface of a thin planar molded article of 150 mm
(width).times.150 mm (length).times.1.2 mm (thickness) obtained by
injection molding was visually observed, and the number of
dispersion defects (e.g., swelling and blistering) of reinforcing
fibers was measured. Measurements were made on 20 samples, and
using as a criterion the average number of defects obtained by
dividing the total number of dispersion defects by the number of
samples, evaluation was carried out on the following 4-point scale.
"Excellent" and "good" were evaluated as acceptable.
[0375] Excellent: No dispersion defects are observed in all the
molded articles. Surface appearance is particularly excellent.
[0376] Good: The average number of defects is more than 0 and less
than 0.1/sample. Surface appearance is excellent.
[0377] Fair: The average number of defects is 0.1/sample to less
than 0.5/sample. Surface appearance is somewhat poor.
[0378] Bad: The average number of defects is not less than
0.5/sample. Surface appearance is poor.
(9) Measurement of the Content of Reinforcing Fiber Substrate (A')
in Molding Material
[0379] A molding material was cut into 20-mm-square pieces, and
poly (phenylene ether ether ketone) oligomers (B) were extracted by
Soxhlet extraction using 100 g of chloroform at 80.degree. C. over
5 hours. The residue was dried, and the fiber weight content was
calculated from the weight difference before and after extraction.
The number of measurements n was 3.
(10) Evaluation of Impregnation Rate of Poly (Phenylene Ether Ether
Ketone) Oligomer (B) or Poly (Phenylene Ether Ether Ketone) (B') in
Molding Material
[0380] The cross-section through the thickness of a molding
material was observed for measurement as described below. A molding
material was embedded in epoxy resin to prepare a sample, which was
polished until the cross-section through the thickness of the
molding material was able to be satisfactorily observed. Using the
sample obtained here, the area of 500 .mu.m (thickness.times.width)
of the molding material was photographed at 400.times.
magnification using an ultra-deep color 3D profile measuring
microscope VK-9500 (controller unit)/VK-9510 (measuring unit)
(manufactured by KEYENCE CORPORATION.). In the photographed image,
the area of parts occupied by the resin and the area of void parts
were determined, and the impregnation rate was calculated by the
following equation.
Impregnation rate(%)=100.times.(total area of parts occupied by
resin)/{(total area of parts occupied by resin)+(total area of void
parts)}
[0381] The impregnation rate of a poly (phenylene ether ether
ketone) oligomer (B) or poly (phenylene ether ether ketone) (B')
was evaluated on the following 3-point scale using the impregnation
rate as a criterion, and "good" and "fair" were evaluated as
acceptable.
[0382] Good: Impregnation rate is 80% to 100%.
[0383] Fair: Impregnation rate is 20% to less than 80%.
[0384] Bad: Impregnation rate is less than 20%.
(11) Evaluation of Drape Property of Molding Material
[0385] The drape property in the present invention refers to the
extent to which a molding material flexibly follows a mold without
causing breakage of the molding material or fibers when the molding
material is deformed along the mold. In the present invention, an
evaluation fixture 5 shown in FIG. 12 was used for evaluation. The
fixture 5 had a length (a) of 100 mm, a height (b) of 100 mm, and a
block corner angle (d) of 90.degree.. The prepreg obtained was cut
into 100 mm (length).times.10 mm (width) to prepare a test sample
6. In this case, the longitudinal direction of the sample is made
to agree with the longitudinal direction of a reinforcing fiber
substrate (A'). As shown in FIG. 12, 200 g of a heavy bob 7 was
attached to one end of the sample, and the other end and the
midpoint were fastened to the fixture 12 with clamps 8 (length of
fastened part (c): 50 mm). The molding material is observed when
the heavy bob 7 is stationary. The drape property of each sample
was evaluated on a 4-point scale according to the following
criteria.
[0386] Excellent: The sample is substantially in contact with the
block face forming an angle of 90.degree. without breakage of the
molding material or reinforcing fibers. (Drape property is
particularly excellent.)
[0387] Good: The sample is bent at the block corner forming an
angle of 90.degree. without breakage of the molding material or
reinforcing fibers. When another force is applied, the sample can
be forcibly in contact with the block face without breakage of the
prepreg or reinforcing fibers. (Drape property is excellent.)
[0388] Fair: The sample is bent at the block corner forming an
angle of 90.degree. without breakage of the molding material or
reinforcing fibers. Even when another force is applied, the sample
cannot be forcibly in contact with the block face, or breakage of
the molding material and reinforcing fibers occurs. (Drape property
is somewhat poor.)
[0389] Bad: The sample is bent at the block corner forming an angle
of 90.degree., but breakage of the prepreg and reinforcing fibers
occurs; or the sample is not bent at the block corner forming an
angle of 90.degree.. (Drape property is poor.)
(12) Void Fraction Evaluation of Molded Article Obtained Using
Molding Material or Fiber-Reinforced Composite Material
[0390] The cross-section through the thickness of a molded article
or fiber-reinforced composite material was observed for measurement
as described below. A molded article or fiber-reinforced composite
material was embedded in epoxy resin to prepare a sample, which was
polished until the cross-section through the thickness of the
molded article or fiber-reinforced composite material was able to
be satisfactorily observed. Using the sample obtained here, the
area of 500 .mu.m (thickness.times.width) of the molded article or
fiber-reinforced composite material was photographed at 400.times.
magnification using an ultra-deep color 3D profile measuring
microscope VK-9500 (controller unit)/VK-9510 (measuring unit)
(manufactured by KEYENCE CORPORATION.). In the photographed image,
the area of void parts was determined, and the impregnation rate
was calculated by the following equation.
Void fraction(%)=100.times.(total area of void parts)/(total area
of observation sites of molded article or fiber-reinforced
composite material)
[0391] The void fraction of a molded article was evaluated on the
following 3-point scale using the void fraction as a criterion. For
molded articles obtained using a molding material, "good" and
"fair" were evaluated as acceptable, and for fiber-reinforced
composite materials, "good" was evaluated as acceptable.
[0392] Good: Void fraction is 0% to 20%. Variation in physical
properties is very little.
[0393] Fair: Void fraction is more than 20% and not more than 40%.
Variation in physical properties is little.
[0394] Bad: Void fraction is more than 40%. Variation in physical
properties is large.
(13) Melt Viscosity Measurement
[0395] Melt viscosities were measured with a dynamic
viscoelasticity measuring apparatus under the following
conditions.
[0396] Apparatus: ARES manufactured by TA Instruments
[0397] Plate: Parallel plate, diameter 40 mm
(14) Content of Reinforcing Fiber Substrate (A') in
Fiber-Reinforced Composite Material
[0398] The content of a reinforcing fiber substrate (A') in a
fiber-reinforced composite material was determined from the weight
of the reinforcing fiber substrate (A') used to produce the
fiber-reinforced composite material and the weight of the
fiber-reinforced composite material obtained using the following
equation.
Content of reinforcing fiber substrate (A') (wt
%)=100.times.(weight of reinforcing fiber substrate (A')
used)/(weight of fiber-reinforced composite material obtained)
Preparation of Poly (Phenylene Ether Ether Ketone) Oligomer (B)
(Reference Example 1) Method for Producing Poly (Phenylene Ether
Ether Ketone) Oligomer (B) [B1]
[0399] To a four-necked flask equipped with a stirrer, nitrogen
inlet tube, Dean-Stark apparatus, condenser tube, and thermometer,
2.40 g (11 mmol) of 4,4'-difluoro benzophenone, 1.10 g (10 mmol) of
hydroquinone, 1.52 g (11 mmol) of anhydrous potassium carbonate,
100 mL of dimethyl sulfoxide, and 10 mL of toluene were loaded. The
amount of dimethyl sulfoxide per 1.0 mol of the benzene ring
component in the resulting mixture is 3.13 liters. The temperature
was raised to 140.degree. C. under nitrogen flow and maintained at
140.degree. C. for 1 hour. The temperature was then raised to
160.degree. C. and maintained at 160.degree. C. for 4 hours to
allow the mixture to react. After completion of the reaction, the
temperature was cooled to room temperature to prepare a reaction
mixture.
[0400] About 0.2 g of the reaction mixture obtained was weighed and
diluted with about 4.5 g of THF. THF-insoluble matter was separated
and removed by filtration to prepare a sample for high-performance
liquid chromatography analysis. The reaction mixture was analyzed
to show that consecutive five types of cyclic poly (phenylene ether
ether ketone)s having a number of repeating units (m) of 2 to 6
were formed, and the yield of poly (phenylene ether ether ketone)
oligomers (B) from hydroquinone was 15.3%.
[0401] Fifty grams of the reaction mixture thus obtained was
collected, and 150 g of 1 wt % aqueous acetic acid solution was
added thereto. After stirring the resulting mixture into a slurry,
the slurry was heated to 70.degree. C., and stirring was continued
for 30 minutes. The slurry was filtered through a glass filter
(average pore size: 10 to 16 .mu.m) to obtain solid matter. The
solid matter obtained was dispersed in 50 g of deionized water,
maintained at 70.degree. C. for 30 minutes, and filtered to obtain
solid matter. This procedure was repeated three times. The solid
matter obtained was subjected to vacuum drying at 70.degree. C.
overnight to obtain about 1.24 g of dry solid.
[0402] Further, 1.0 g of the dry solid obtained above was subjected
to Soxhlet extraction at a bath temperature of 80.degree. C. for 5
hours using 100 g of chloroform. The chloroform was removed from
the resulting extract using an evaporator to obtain solid matter.
Two grams of chloroform was added to the solid matter, and then the
resulting mixture was made into a dispersion using an ultrasonic
washer, which dispersion was added dropwise to 30 g of methanol.
The resulting precipitate was separated by filtration using a
filter paper with an average pore size of 1 .mu.m, and then
subjected to vacuum drying at 70.degree. C. for 3 hours to obtain a
white solid. The weight of the white solid obtained was 0.14 g, and
the yield from hydroquinone used in the reaction was 14.0%.
[0403] This white powder was confirmed to be a compound composed of
phenylene ether ketone units by the absorption spectrum obtained by
infrared spectroscopic analysis. Mass spectrometric analysis
(apparatus; M-1200H manufactured by Hitachi) of the components
fractionated by high-performance liquid chromatography and the
molecular weight information obtained by MALDI-TOF-MS showed that
this white powder was a poly (phenylene ether ether ketone)
oligomer (B) mainly composed of a mixture of consecutive five types
of cyclic poly (phenylene ether ether ketone)s having a number of
repeating units (m) of 2 to 6. Further, the weight fraction of the
cyclic poly (phenylene ether ether ketone) mixture in the poly
(phenylene ether ether ketone) oligomer (B) was 81%. The component
other than the cyclic poly (phenylene ether ether ketone) in the
poly (phenylene ether ether ketone) oligomer (B) was a linear poly
(phenylene ether ether ketone) oligomer.
[0404] The melting point of such a poly (phenylene ether ether
ketone) oligomer (B) was measured to be 163.degree. C. The reduced
viscosity of the poly (phenylene ether ether ketone) oligomer (B)
was measured to be less than 0.02 dL/g.
[0405] Further, the chloroform insoluble solid matter, which was
obtained in the recovery of the poly (phenylene ether ether ketone)
oligomer (B) by Soxhlet extraction described above, was subjected
to vacuum drying at 70.degree. C. overnight to obtain about 0.85 g
of off-white solid matter. The solid matter was analyzed, and it
was confirmed to be a linear poly (phenylene ether ether ketone) by
the absorption spectrum obtained by infrared spectroscopic
analysis. Further, the reduced viscosity of this linear poly
(phenylene ether ether ketone) was measured to be 0.45 dL/g.
[0406] Further, the melt viscosity was measured, and the melt
viscosity at 230.degree. C. of the poly (phenylene ether ether
ketone) oligomer (B) was 0.034 Pas.
(Reference Example 2) Method for Producing Poly (Phenylene Ether
Ether Ketone) Oligomer (B) [B2]
[0407] Here, a method for producing a poly (phenylene ether ether
ketone) oligomer (B) will be described, which method uses the
linear poly (phenylene ether ether ketone) produced as a by-product
in the method for producing a poly (phenylene ether ether ketone)
oligomer (B).
[0408] To a 100-mL autoclave equipped with a stirrer, 0.22 g (1
mmol) of 4,4'-difluoro benzophenone, 0.11 g (1 mmol) of
hydroquinone, 0.14 g (1 mmol) of anhydrous potassium carbonate,
1.15 g (4 mmol) of the linear poly (phenylene ether ether ketone)
obtained by the method described in Reference Example 1 (reduced
viscosity; 0.45 dL/g), and 50 mL of N-methyl-2-pyrrolidone were
loaded. The amount of N-methyl-2-pyrrolidone per 1.0 mol of the
benzene ring component in the resulting mixture is 3.33 liters.
[0409] At room temperature and under normal pressure, the reaction
vessel was hermetically sealed under nitrogen gas. Thereafter, with
stirring at 400 rpm, the temperature was raised from room
temperature to 140.degree. C. and maintained at 140.degree. C. for
1 hour. The temperature was then raised to 180.degree. C. and
maintained at 180.degree. C. for 3 hours, and then the temperature
was raised to 230.degree. C. and maintained at 230.degree. C. for 5
hours to allow the mixture to react.
[0410] About 0.2 g of the reaction mixture obtained was weighed and
diluted with about 4.5 g of THF. THF-insoluble matter was separated
and removed by filtration to prepare a sample for high-performance
liquid chromatography analysis. The reaction mixture was analyzed
to show that consecutive seven types of cyclic poly (phenylene
ether ether ketone)s having a number of repeating units (m) of 2 to
8 were formed, and the yield of the cyclic poly (phenylene ether
ether ketone) mixture was 8.3%.
[0411] Further, recovery of poly (phenylene ether ether ketone)
oligomer (B) from the reaction mixture was performed according to
the method described in Reference Example 1 to obtain a poly
(phenylene ether ether ketone) oligomer (B) in 8.0% yield. The poly
(phenylene ether ether ketone) oligomer (B) obtained was analyzed,
and it was found that the weight fraction of the cyclic poly
(phenylene ether ether ketone) mixture in the poly (phenylene ether
ether ketone) oligomer (B) was 77%, and the poly (phenylene ether
ether ketone) oligomer (B) had a melting point of 165.degree. C.
Further, it was also found that the poly (phenylene ether ether
ketone) oligomer (B) had a reduced viscosity of less than 0.02
dL/g.
[0412] Further, the melt viscosity was measured, and the melt
viscosity at 230.degree. C. of the poly (phenylene ether ether
ketone) oligomer (B) was 0.030 Pas.
Reference Example 3
[0413] Here, synthesis in accordance with the common method for
producing a poly (phenylene ether ether ketone) described in
Examples of JP 2007-506833 A will be described.
[0414] To a four-necked flask equipped with a stirrer, nitrogen
inlet tube, Dean-Stark apparatus, condenser tube, and thermometer,
22.5 g (103 mmol) of 4,4'-difluoro benzophenone, 11.0 g (100 mmol)
of hydroquinone, and 49 g of diphenyl sulfone were loaded. The
amount of diphenyl sulfone per 1.0 mol of the benzene ring
component in the resulting mixture is about 0.16 liters. The
temperature was raised to 140.degree. C. under nitrogen flow to
form a substantially colorless solution. At this temperature, 10.6
g (100 mmol) of anhydrous sodium carbonate and 0.28 g (2 mmol) of
anhydrous potassium carbonate were added thereto. The temperature
was raised to 200.degree. C. and maintained there for 1 hour,
raised to 250.degree. C. and maintained there for 1 hour, and then
raised to 315.degree. C. and maintained there for 3 hours.
[0415] The reaction mixture obtained was analyzed by
high-performance liquid chromatography to show that the yield of
the cyclic poly (phenylene ether ether ketone) mixture from
hydroquinone was a trace amount of less than 1%.
[0416] The reaction mixture was allowed to cool and pulverized, and
the resultant was washed with water and acetone to remove
by-product salts and diphenyl sulfone. The polymer obtained was
dried in a hot-air dryer at 120.degree. C. to obtain powder.
[0417] About 1.0 g of the powder obtained was subjected to Soxhlet
extraction at a bath temperature of 80.degree. C. for 5 hours using
100 g of chloroform. The chloroform was removed from the resulting
extract using an evaporator to obtain a small amount of chloroform
soluble matter. The yield of the recovered chloroform soluble
matter from hydroquinone used in the reaction was 1.2%. The
recovered chloroform soluble matter was analyzed by
high-performance liquid chromatography, and it was found that the
chloroform soluble matter contained a cyclic poly (phenylene ether
ether ketone) and a linear poly (phenylene ether ether ketone)
oligomer. This linear poly (phenylene ether ether ketone) oligomer
is a compound that is difficult to separate from the cyclic poly
(phenylene ether ether ketone) because it is similar to the cyclic
poly (phenylene ether ether ketone) in terms of properties such as
solvent solubility. Further, the cyclic poly (phenylene ether ether
ketone) mixture contained in the recovered chloroform soluble
matter described above was composed of cyclic poly (phenylene ether
ether ketone)s having a number of repeating units (m) of 4 and 5,
and, furthermore, the weight fraction of cyclic poly (phenylene
ether ether ketone) having a number of repeating units (m) of 4 was
80% or more. Further, the melting point of the recovered chloroform
soluble matter was about 320.degree. C. This is presumably due to
the high content of the tetrameric cyclic poly (phenylene ether
ether ketone) (m=4) in the chloroform soluble matter obtained by
this method.
[0418] Further, in the Soxhlet extraction described above, the
chloroform insoluble solid matter was subjected to vacuum drying at
70.degree. C. overnight to obtain about 0.98 g of off-white solid
matter. The solid matter was analyzed, and it was confirmed to be a
linear poly (phenylene ether ether ketone) by the absorption
spectrum obtained by infrared spectroscopic analysis. Further, the
reduced viscosity of this linear poly (phenylene ether ether
ketone) was measured to be 0.75 dL/g.
[0419] Further, the melt viscosity was measured, and the melt
viscosity at 350.degree. C. of the poly (phenylene ether ether
ketone) oligomer (B) was 0.15 Pas.
(Reference Example 4) Method for Producing Poly (Phenylene Ether
Ether Ketone) Oligomer (B) [B3]
[0420] Here, a method for producing a cyclic poly (phenylene ether
ether ketone) using the linear poly (phenylene ether ether ketone)
(reduced viscosity; 0.75 dL/g) obtained by the method of Reference
Example 3 will be described.
[0421] To a 1-L autoclave equipped with a stirrer, 14.4 g (50 mmol)
of the poly (phenylene ether ether ketone) obtained by the method
described in Reference Example 3, 1.52 g (10 mmol) of cesium
fluoride, and 500 mL of N-methyl-2-pyrrolidone were loaded. The
amount of N-methyl-2-pyrrolidone per 1.0 mol of the benzene ring
component in the resulting mixture is 3.33 liters.
[0422] At room temperature and under normal pressure, the reaction
vessel was hermetically sealed under nitrogen gas. Thereafter, with
stirring at 400 rpm, the temperature was raised from room
temperature to 140.degree. C. and maintained at 140.degree. C. for
1 hour. The temperature was then raised to 180.degree. C. and
maintained at 180.degree. C. for 3 hours, and then the temperature
was raised to 230.degree. C. and maintained at 230.degree. C. for 5
hours to allow the mixture to react.
[0423] About 0.2 g of the reaction mixture obtained was weighed and
diluted with about 4.5 g of THF. THF-insoluble matter was separated
and removed by filtration to prepare a sample for high-performance
liquid chromatography analysis. The reaction mixture was analyzed
to show that consecutive seven types of cyclic poly (phenylene
ether ether ketone) mixture having a number of repeating units (m)
of 2 to 8 were formed, and the yield of the cyclic poly (phenylene
ether ether ketone) mixture was 13.7%. (The yield of the cyclic
poly (phenylene ether ether ketone) mixture was calculated by
comparing the amount of cyclic poly (phenylene ether ether ketone)
formed with the amount of poly (phenylene ether ether ketone) used
in the reaction.)
[0424] Further, recovery of poly (phenylene ether ether ketone)
oligomer (B) from the reaction mixture was performed according to
the method described in Reference Example 1 to obtain a poly
(phenylene ether ether ketone) oligomer (B) in 13.7% yield. It was
found that the weight fraction of the cyclic poly (phenylene ether
ether ketone) mixture in the poly (phenylene ether ether ketone)
oligomer (B) obtained was 79%, and the poly (phenylene ether ether
ketone) oligomer (B) had a melting point of 165.degree. C. Further,
it was also found that the poly (phenylene ether ether ketone)
oligomer (B) was less than 0.02 dL/g.
[0425] Further, the melt viscosity was measured, and the melt
viscosity at 230.degree. C. of the poly (phenylene ether ether
ketone) oligomer (B) was 0.036 Pas.
<Molding Material>
Example 1
[0426] The poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1 was melted in a molten bath at
230.degree. C. and fed to a kiss coater with a gear pump. The poly
(phenylene ether ether ketone) oligomer (B) was applied from the
kiss coater onto a roll heated to 230.degree. C. to form a
coating.
[0427] Carbon fibers "TORAYCA" (registered trademark) T700S-24K
(available from TORAY INDUSTRIES, INC.) were passed in contact with
the roll to deposit the poly (phenylene ether ether ketone)
oligomer (B) thereon in a given amount per unit length of a
reinforcing fiber bundle (A).
[0428] The carbon fiber with the poly (phenylene ether ether
ketone) oligomer (B) deposited thereon was passed through 10 rolls
heated to 230.degree. C. (.phi.: 50 mm) which are arranged
alternately above and below on a straight line and freely rotate
with the aid of bearings, whereby the poly (phenylene ether ether
ketone) oligomer (B) was thoroughly impregnated into the
reinforcing fiber bundle (A).
[0429] Next, VICTREX "PEEK" (registered trademark) 151G (polyether
ether ketone resin available from Victrex-MC, Inc., melting point:
343.degree. C.) used as a thermoplastic resin (C) was melted in a
single-screw extruder at 400.degree. C. The melted thermoplastic
resin (C) was extruded into a crosshead die mounted at the end of
the extruder, and simultaneously therewith, the composite obtained
was continuously fed into the crosshead die, whereby the composite
was coated with the melted thermoplastic resin (C). In this
process, the discharge rate of the thermoplastic resin (C) was
adjusted to adjust the content of the reinforcing fiber bundle (A)
to a predetermined value.
[0430] The strand obtained by the method described above was cooled
and then cut with a cutter to a length of 7 mm to obtain columnar
pellets (long-fiber pellets) having a core-sheath structure. The
long-fiber pellets obtained did not have fuzz due to transportation
and exhibited good handleability.
[0431] The long-fiber pellets obtained were dried under vacuum at
150.degree. C. for 5 hours or more. The dried long-fiber pellets
were subjected to molding using molds for various test pieces using
an injection molding machine Model J150EII-P manufactured by Japan
Steel Works, LTD. Conditions were as follows: injection molding
temperature: 400.degree. C., mold temperature: 160.degree. C., and
cooling time: 30 seconds. After molding, the resulting molded
article was dried under vacuum at 80.degree. C. for 12 hours and
stored in a desiccator at room temperature for 3 hours, and the
resulting dried test piece was evaluated. The flexural test of the
molded article obtained was carried out in accordance with ASTM
D790 (1997) to measure the flexural strength and flexural modulus
under test conditions of a support span of 100 mm, which was set
using a 3-point bend fixture (indenter: 10 mm, fulcrum: 4 mm), and
a crosshead speed of 2.8 mm/min. "INSTRON" (registered trademark)
universal tester Model 4201 (manufactured by INSTRON) was used as a
tester. For Izod impact test of the molded article obtained, a mold
notched Izod impact test was performed in accordance with ASTM D256
(1993). The test piece with a thickness of 3.2 mm and a moisture
content of 0.1 wt % or less was used to measure the Izod impact
strength (Jim). Evaluation results are shown in Table 1.
Example 2
[0432] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the poly (phenylene ether ether ketone) oligomer (B) prepared
in Reference Example 2 was used. Injection molding was carried out
in the same manner as in Example 1 using the long-fiber pellets
obtained, and evaluations were carried out. The process conditions
and the evaluation results are shown in Table 1.
Comparative Example 1
[0433] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the poly (phenylene ether ether ketone) oligomer (B) prepared
in Reference Example 3 was used and that the molten bath
temperature, the roll temperature, and the bearing temperature were
changed to 340.degree. C. Injection molding was carried out in the
same manner as in Example 1 using the long-fiber pellets obtained,
and evaluations were carried out. The process conditions and the
evaluation results are shown in Table 1.
Example 3
[0434] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the poly (phenylene ether ether ketone) oligomer (B) prepared
in Reference Example 4 was used. Injection molding was carried out
in the same manner as in Example 1 using the long-fiber pellets
obtained, and evaluations were carried out. The process conditions
and the evaluation results are shown in Table 1.
[0435] It is clear from the results of Examples 1 to 3 that
regardless of the method for producing a poly (phenylene ether
ether ketone) oligomer (B), by using a poly (phenylene ether ether
ketone) oligomer (B) having a melting point of not higher than
270.degree. C., the poly (phenylene ether ether ketone) oligomer
(B) excellently impregnates into a continuous reinforcing fiber
bundle (A), and a molding material can be easily produced. The
molded article obtained by using the resulting molding material had
excellent dynamic properties and appearance quality.
[0436] It is clear from Comparative Example 1 that when a poly
(phenylene ether ether ketone) composition having a melting point
of higher than 270.degree. C. is used, the poly (phenylene ether
ether ketone) composition is difficult to melt, resulting in poor
impregnation into a continuous reinforcing fiber bundle (A).
Moreover, this molding material is also poor in fiber
dispersibility during molding, and the molded article obtained by
using this molding material was observed to have defects in
appearance.
Example 4
[0437] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 18 wt % and that
the amount of the thermoplastic resin (C) was changed to 62 wt %.
Injection molding was carried out in the same manner as in Example
1 using the long-fiber pellets obtained, and evaluations were
carried out. The process conditions and the evaluation results are
shown in Table 1.
Comparative Example 2
[0438] Production of columnar pellets (long-fiber pellets) having a
core-sheath structure was attempted in the same manner as in
Example 1 except that the poly (phenylene ether ether ketone)
oligomer (B) and a molten bath were not used and that the amount of
the thermoplastic resin (C) was changed to 80 wt %, but a large
number of molding materials were defective products. Injection
molding was attempted in the same manner as in Example 1 using the
long-fiber pellets obtained, but the molding could not be achieved
because of a poor bite into a screw. The process conditions are
shown in Table 1.
Comparative Example 3
[0439] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 30 wt % and that
the amount of the thermoplastic resin (C) was changed to 50 wt %.
Injection molding was carried out in the same manner as in Example
1 using the long-fiber pellets obtained, and evaluations were
carried out. The process conditions and the evaluation results are
shown in Table 1.
[0440] It is clear from Example 4 that even when the amount of the
poly (phenylene ether ether ketone) oligomer (B) is 18 wt %, the
poly (phenylene ether ether ketone) oligomer (B) excellently
impregnates into a continuous reinforcing fiber bundle (A), and a
molding material is easily produced. The molded article obtained by
using the resulting molding material had excellent appearance
quality.
[0441] It is clear from Comparative Example 2 that when the poly
(phenylene ether ether ketone) oligomer (B) is not used, the
productivity and moldability of the molding material are very poor
because the continuous reinforcing fiber bundle (A) is poorly
impregnated only with the high-viscosity thermoplastic resin
(C).
[0442] It is clear from Comparative Example 3 that when the amount
of the poly (phenylene ether ether ketone) oligomer (B) is 30 wt %,
the productivity of the molding material is excellent, but the
molded article obtained by using the resulting molding material has
very poor dynamic properties.
Example 5
[0443] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 3 wt %; the
amount of the thermoplastic resin (C) was changed to 87 wt %; and
the amount of the reinforcing fiber bundle (A) was changed to 10 wt
%. Injection molding was carried out in the same manner as in
Example 1 using the long-fiber pellets obtained, and evaluations
were carried out. The process conditions and the evaluation results
are shown in Table 1.
Example 6
[0444] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 15 wt %; the
amount of the thermoplastic resin (C) was changed to 55 wt %; and
the amount of the reinforcing fiber bundle (A) was changed to 30 wt
%. Injection molding was carried out in the same manner as in
Example 1 using the long-fiber pellets obtained, and evaluations
were carried out. The process conditions and the evaluation results
are shown in Table 1.
[0445] It is clear from Examples 5 and 6 that by using a poly
(phenylene ether ether ketone) oligomer (B) having a melting point
of not higher than 270.degree. C., even when the fiber contents of
the molding materials are 10 wt % and 30 wt %, the poly (phenylene
ether ether ketone) oligomer (B) excellently impregnates into a
continuous reinforcing fiber bundle (A); the productivity of the
molding material is excellent; and a molding material can be easily
produced. The molded article obtained by using the resulting
molding material had excellent dynamic properties and appearance
quality.
Example 7
[0446] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that "AMILAN" (registered trademark) CM3001 (nylon 66 resin
available from TORAY INDUSTRIES, INC., melting point: 265.degree.
C.) was used as a thermoplastic resin (C) in place of poly
(phenylene ether ether ketone) and that the extrusion temperature
of the thermoplastic resin (C) during the production of a molding
material was 280.degree. C. Injection molding was carried out in
the same manner as in Example 1 except that using the long-fiber
pellets obtained, the injection molding temperature and the mold
temperature were changed to 300.degree. C. and 80.degree. C.,
respectively, and evaluations were carried out. The process
conditions and the evaluation results are shown in Table 1.
Example 8
[0447] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that "TORELINA" (registered trademark) A900 (polyphenylene sulfide
resin available from TORAY INDUSTRIES, INC., melting point:
278.degree. C.) was used as a thermoplastic resin (C) in place of
poly (phenylene ether ether ketone) and that the extrusion
temperature of the thermoplastic resin (C) during the production of
a molding material was 330.degree. C. Injection molding was carried
out in the same manner as in Example 1 except that using the
long-fiber pellets obtained, the injection molding temperature and
the mold temperature were changed to 320.degree. C. and 150.degree.
C., respectively, and evaluations were carried out. The process
conditions and the evaluation results are shown in Table 1.
[0448] It is clear from Examples 7 and 8 that by using a poly
(phenylene ether ether ketone) oligomer (B) having a melting point
of not higher than 270.degree. C., the molding temperature of the
resulting molding material can be lowered, which allows resins
other than poly (phenylene ether ether ketone) resin, such as nylon
66 resin and PPS resin, to be selected as a thermoplastic resin
(C). The molding material obtained was excellent in fiber
dispersibility during molding and had excellent dynamic properties
and appearance quality.
Example 9
[0449] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 1 except
that cesium fluoride was added as a polymerization catalyst (D) to
a molten bath in an amount of 5 mol % based on the repeating unit
of the formula: --(O-Ph-O-Ph-CO-Ph)-, which is a main structural
unit of the poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1. Injection molding was carried out
in the same manner as in Example 1 using the long-fiber pellets
obtained, and evaluations were carried out. The process conditions
and the evaluation results are shown in Table 1.
[0450] It is clear from Example 9 that by using a poly (phenylene
ether ether ketone) oligomer (B) having a melting point of not
higher than 270.degree. C. and adding a polymerization catalyst (D)
to the molding material of the present invention, the molded
article obtained by using the resulting molding material has
excellent dynamic properties and appearance quality.
TABLE-US-00001 TABLE 1 Comparative Comparative Comparative Example
1 Example 2 Example 1 Example 3 Example 4 Example 2 Example 3
(Composition) Component (A): Carbon fiber wt % 20 20 20 20 20 20 20
Component (B): Poly (phenylene Type Reference Reference Reference
Reference Reference -- Reference ether ether ketone) oligomer
Example 1 Example 2 Example 3 Example 4 Example 1 Example 1 wt % 5
5 5 5 18 30 Component (C): Thermoplastic Type PEEK PEEK PEEK PEEK
PEEK PEEK PEEK resin wt % 75 75 75 75 62 80 50 Component (D):
Polymerization Type -- -- -- -- -- -- -- catalyst mol % (Process
conditions) Molten bath temperarute .degree. C. 230 230 340 230 230
-- 230 Roll temperature .degree. C. 230 230 340 230 230 230 230
Bearing temperature .degree. C. 230 230 340 230 230 230 230
Extrusion temperature .degree. C. 400 400 400 400 400 400 400
Injection-molding temperature .degree. C. 400 400 400 400 400 400
400 Mold temperature .degree. C. 160 160 160 160 160 160 160
(Productivity of molding material) Productivity evaluation of --
good good bad good good bad fair molding material (Properties of
Moled article) Number-average fiber length mm 0.50 0.45 0.40 0.45
0.55 -- 0.55 Weight-average fiber length mm 0.70 0.60 0.55 0.60
0.75 -- 0.80 Density g/cm.sup.3 1.37 1.37 1.36 1.37 1.37 -- 1.37
Flexural modulus GPa 15 15 15 15 15 -- 13 Flexural strength MPa 260
255 235 260 220 -- 130 Izod impact J/m 120 115 95 120 110 -- 30
Appearance evaluation -- excellent excellent fair excellent
excellent -- excellent Example 5 Example 6 Example 7 Example 8
Example 9 (Composition) Component (A): Carbon fiber wt % 10 30 20
20 20 Component (B): Poly (phenylene Type Reference Reference
Reference Reference Reference ether ether ketone) oligomer Example
1 Example 1 Example 1 Example 1 Example 1 wt % 3 15 5 5 5 Component
(C): Thermoplastic Type PEEK PEEK Nylon PPS PEEK resin wt % 87 55
75 75 75 Component (D): Polymerization Type -- -- -- -- CsF
catalyst mol % 5 (Process conditions) Molten bath temperarute
.degree. C. 230 230 230 230 230 Roll temperature .degree. C. 230
230 230 230 230 Bearing temperature .degree. C. 230 230 230 230 230
Extrusion temperature .degree. C. 400 400 280 330 400
Injection-molding temperature .degree. C. 400 400 300 320 400 Mold
temperature .degree. C. 160 160 80 150 160 (Productivity of molding
material) Productivity evaluation of -- good good good good good
molding material (Properties of Moled article) Number-average fiber
length mm 0.60 0.40 0.50 0.50 0.45 Weight-average fiber length mm
0.75 0.60 0.65 0.65 0.60 Density g/cm.sup.3 1.34 1.41 1.23 1.41
1.37 Flexural modulus GPa 10 20 14 16 15 Flexural strength MPa 200
330 320 240 265 Izod impact J/m 90 140 100 85 120 Appearance
evaluation -- excellent excellent good good excellent
Example 10
[0451] To the poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1, cesium fluoride was added as a
polymerization catalyst (D) in an amount of 5 mol % based on the
repeating unit of the formula: --(O-Ph-O-Ph-CO-Ph)-, which is a
main structural unit of the poly (phenylene ether ether ketone)
oligomer (B), and the resulting mixture was melted in a molten bath
at 230.degree. C. to obtain a molten mixture. The molten mixture
obtained was fed to a kiss coater with a gear pump. The molten
mixture was applied from the kiss coater onto a roll heated to
230.degree. C. to form a coating.
[0452] Carbon fibers "TORAYCA" (registered trademark) T700S-24K
(available from TORAY INDUSTRIES, INC.) were passed in contact with
the roll to obtain a composite on which the molten mixture was
deposited in a given amount per unit length of a reinforcing fiber
bundle (A).
[0453] The composite was fed into a furnace heated at 300.degree.
C., passed through 10 rolls (.phi.: 50 mm) that are arranged
alternately above and below on a straight line and freely rotate
with the aid of bearings, and passed through 10 roll bars (.phi.:
200 mm) placed in the furnace in a zigzag pattern more than once in
loops. In such a manner, it spended 30 minutes in total to convert
the poly (phenylene ether ether ketone) oligomer (B) into a poly
(phenylene ether ether ketone) (B') while being impregnated
thoroughly into a reinforcing fiber bundle (A).
[0454] Next, VICTREX "PEEK" (registered trademark) 151G (polyether
ether ketone resin available from Victrex-MC, Inc., melting point:
343.degree. C.) used as a thermoplastic resin (C) was melted in a
single-screw extruder at 400.degree. C. The melted thermoplastic
resin (C) was extruded into a crosshead die mounted at the end of
the extruder, and simultaneously therewith, the composite obtained
was continuously fed into the crosshead die, whereby the composite
was coated with the melted thermoplastic resin (C). In this
process, the discharge rate of the thermoplastic resin (C) was
adjusted to adjust the content of the reinforcing fiber bundle (A)
to a predetermined value.
[0455] The strand obtained by the method described above was cooled
and then cut with a cutter to a length of 7 mm to obtain columnar
pellets (long-fiber pellets) having a core-sheath structure. The
long-fiber pellets obtained did not have fuzz due to transportation
and exhibited good handleability.
[0456] From the long-fiber pellets obtained, the coating of the
thermoplastic resin (C) was peeled off, and further the reinforcing
fibers (A) were removed, thereby separating the poly (phenylene
ether ether ketone) (B'). The poly (phenylene ether ether ketone)
(B') obtained here was subjected to melting point measurement and
viscosity measurement.
[0457] The long-fiber pellets obtained were dried under vacuum at
150.degree. C. for 5 hours or more. The dried long-fiber pellets
were subjected to molding using molds for various test pieces using
an injection molding machine Model J150EII-P manufactured by Japan
Steel Works, LTD. Conditions were as follows: injection molding
temperature: 400.degree. C., mold temperature: 160.degree. C., and
cooling time: 30 seconds. After molding, the resulting molded
article was dried under vacuum at 80.degree. C. for 12 hours and
stored in a desiccator at room temperature for 3 hours, and the
resulting dried test piece was evaluated. The flexural test of the
molded article obtained was carried out in accordance with ASTM
D790 (1997) to measure the flexural strength and flexural modulus
under test conditions of a support span of 100 mm, which was set
using a 3-point bend fixture (indenter: 10 mm, fulcrum: 4 mm), and
a crosshead speed of 2.8 mm/min. "INSTRON" (registered trademark)
universal tester Model 4201 (manufactured by INSTRON) was used as a
tester. For Izod impact test of the molded article obtained, a mold
notched Izod impact test was performed in accordance with ASTM D256
(1993). The test piece with a thickness of 3.2 mm and a moisture
content of 0.1 wt % or less was used to measure the Izod impact
strength (J/m). The process conditions and the evaluation results
are shown in Table 2.
Example 11
[0458] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the poly (phenylene ether ether ketone) oligomer (B) prepared
in Reference Example 2 was used. Using the long-fiber pellets
obtained, the poly (phenylene ether ether ketone) (B') was
separated in the same manner as in Example 10 and subjected to
melting point measurement and viscosity measurement. Using the
long-fiber pellets obtained, injection molding was carried out in
the same manner as in Example 10, and evaluations were carried out.
The process conditions and the evaluation results are shown in
Table 2.
Comparative Example 4
[0459] Production of columnar pellets (long-fiber pellets) having a
core-sheath structure was attempted in the same manner as in
Example 10 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 3 was used and that the
molten bath temperature, the roll temperature, and the furnace
temperature were changed to 350.degree. C., but a large number of
molding materials were defective products. This was because
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) into a poly (phenylene ether ether ketone) (B') proceeded in
the molten bath, and impregnation into a continuous reinforcing
fiber bundle (A) became difficult. Using the long-fiber pellets
obtained, the poly (phenylene ether ether ketone) (B') was
separated in the same manner as in Example 10 and subjected to
melting point measurement and viscosity measurement. Injection
molding was attempted in the same manner as in Example 10 using the
long-fiber pellets obtained, but the molding could not be achieved
because of a poor bite into a screw. The process conditions and the
evaluation results are shown in Table 2.
Example 12
[0460] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the poly (phenylene ether ether ketone) oligomer (B) prepared
in Reference Example 4 was used. Using the long-fiber pellets
obtained, the poly (phenylene ether ether ketone) (B') was
separated in the same manner as in Example 10 and subjected to
melting point measurement and viscosity measurement. Using the
long-fiber pellets obtained, injection molding was carried out in
the same manner as in Example 10, and evaluations were carried out.
The process conditions and the evaluation results are shown in
Table 2.
[0461] It is clear from the results of Examples 10 to 12 that
regardless of the method for producing a poly (phenylene ether
ether ketone) oligomer (B), by using a poly (phenylene ether ether
ketone) oligomer (B) having a melting point of not higher than
270.degree. C., the poly (phenylene ether ether ketone) oligomer
(B) excellently impregnates into a continuous reinforcing fiber
bundle (A), and a molding material can be easily produced. In the
molding material obtained, the poly (phenylene ether ether ketone)
oligomer (B) was polymerized into a poly (phenylene ether ether
ketone) (B'), and the molded article obtained by using this molding
material had excellent dynamic properties.
[0462] It is clear from Comparative Example 4 that when a poly
(phenylene ether ether ketone) composition having a melting point
of higher than 270.degree. C. is used, it is necessary to set the
process temperature high, and polymerization of the poly (phenylene
ether ether ketone) composition proceeds in the molten bath,
resulting in significantly reduced impregnation into the
reinforcing fiber bundle (A). It is clear that this molding
material is not only significantly inferior in terms of
productivity and moldability but also inferior in terms of economic
efficiency because it is necessary to set the process temperature
high.
Example 13
[0463] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 18 wt % and that
the amount of the thermoplastic resin (C) was changed to 62 wt %.
Using the long-fiber pellets obtained, the poly (phenylene ether
ether ketone) (B') was separated in the same manner as in Example
10 and subjected to melting point measurement and viscosity
measurement. Using the long-fiber pellets obtained, injection
molding was carried out in the same manner as in Example 10, and
evaluations were carried out. The process conditions and the
evaluation results are shown in Table 2.
Example 14
[0464] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 30 wt % and that
the amount of the thermoplastic resin (C) was changed to 50 wt %.
Using the long-fiber pellets obtained, the poly (phenylene ether
ether ketone) (B') was separated in the same manner as in Example
10 and subjected to melting point measurement and viscosity
measurement. Using the long-fiber pellets obtained, injection
molding was carried out in the same manner as in Example 10, and
evaluations were carried out. The process conditions and the
evaluation results are shown in Table 2.
Comparative Example 5
[0465] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 14 except
that cesium fluoride serving as a polymerization catalyst (D) was
not used. Using the long-fiber pellets obtained, the poly
(phenylene ether ether ketone) (B') was separated in the same
manner as in Example 10 and subjected to melting point measurement
and viscosity measurement. Using the long-fiber pellets obtained,
injection molding was carried out in the same manner as in Example
10, and evaluations were carried out. The process conditions and
the evaluation results are shown in Table 2.
Comparative Example 6
[0466] Production of columnar pellets (long-fiber pellets) having a
core-sheath structure was attempted in the same manner as in
Example 10 except that the poly (phenylene ether ether ketone)
oligomer (B), cesium fluoride serving as a polymerization catalyst
(D), and a molten bath were not used and that the amount of the
thermoplastic resin (C) was changed to 80 wt %, but a large number
of molding materials were defective products. Injection molding was
attempted in the same manner as in Example 10 using the long-fiber
pellets obtained, but the molding could not be achieved because of
a poor bite into a screw. The process conditions are shown in Table
2.
[0467] It is clear from Examples 13 and 14 that even when the
amounts of the poly (phenylene ether ether ketone) oligomer (B) is
18 wt % and 30 wt %, the poly (phenylene ether ether ketone)
oligomer (B) excellently impregnates into a continuous reinforcing
fiber bundle (A), and a molding material is easily produced. In the
molding material obtained, the poly (phenylene ether ether ketone)
oligomer (B) was polymerized into a poly (phenylene ether ether
ketone) (B'), and the molded article obtained by using this molding
material had excellent dynamic properties.
[0468] Comparison between Comparative Example 5 and Example 14
reveals the following. It is clear that in Comparative Example 5,
the poly (phenylene ether ether ketone) oligomer (B) is not
polymerized into a poly (phenylene ether ether ketone) (B') in the
molding material obtained because cesium fluoride serving as a
polymerization catalyst (D) is not used. Further, it is clear that
Comparative Example 5 is significantly inferior to Example 14 in
dynamic properties.
[0469] It is clear from Comparative Example 6 that when the poly
(phenylene ether ether ketone) oligomer (B) and the polymerization
catalyst (D) are not used, the productivity and moldability of the
molding material are very poor because the continuous reinforcing
fiber bundle (A) is poorly impregnated only with the high-viscosity
thermoplastic resin (C).
Example 15
[0470] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the furnace temperature was changed to 350.degree. C. and that
the furnace time was changed to 10 minutes. Using the long-fiber
pellets obtained, the poly (phenylene ether ether ketone) (B') was
separated in the same manner as in Example 10 and subjected to
melting point measurement and viscosity measurement. Using the
long-fiber pellets obtained, injection molding was carried out in
the same manner as in Example 10, and evaluations were carried out.
The process conditions and the evaluation results are shown in
Table 2.
Example 16
[0471] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the furnace temperature was changed to 400.degree. C. and that
the furnace time was changed to 10 minutes. Using the long-fiber
pellets obtained, the poly (phenylene ether ether ketone) (B') was
separated in the same manner as in Example 10 and subjected to
melting point measurement and viscosity measurement. Using the
long-fiber pellets obtained, injection molding was carried out in
the same manner as in Example 10, and evaluations were carried out.
The process conditions and the evaluation results are shown in
Table 2.
[0472] It is clear from Examples 15 and 16 that even when the
furnace temperatures are 350.degree. C. and 400.degree. C., the
poly (phenylene ether ether ketone) oligomer (B) excellently
impregnates into a continuous reinforcing fiber bundle (A), and a
molding material is easily produced. In the molding material
obtained, the poly (phenylene ether ether ketone) oligomer (B) was
polymerized into a poly (phenylene ether ether ketone) (B'), and
the molded article obtained by using this molding material had
excellent dynamic properties. Further, the poly (phenylene ether
ether ketone) (B') in the molding material produced under these
conditions had a melting enthalpy of less than 40 kJ/g, which was
equivalent to that of known poly (phenylene ether ether
ketone).
Example 17
[0473] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 3 wt %; the
amount of the thermoplastic resin (C) was changed to 87 wt %; and
the amount of the reinforcing fiber bundle (A) was changed to 10 wt
%. Using the long-fiber pellets obtained, the poly (phenylene ether
ether ketone) (B') was separated in the same manner as in Example
10 and subjected to melting point measurement and viscosity
measurement. Using the long-fiber pellets obtained, injection
molding was carried out in the same manner as in Example 10, and
evaluations were carried out. The process conditions and the
evaluation results are shown in Table 2.
Example 18
[0474] Columnar pellets (long-fiber pellets) having a core-sheath
structure were prepared in the same manner as in Example 10 except
that the amount of the poly (phenylene ether ether ketone) oligomer
(B) prepared in Reference Example 1 was changed to 15 wt %; the
amount of the thermoplastic resin (C) was changed to 55 wt %; and
the amount of the reinforcing fiber bundle (A) was changed to 30 wt
%. Using the long-fiber pellets obtained, the poly (phenylene ether
ether ketone) (B') was separated in the same manner as in Example
10 and subjected to melting point measurement and viscosity
measurement. Using the long-fiber pellets obtained, injection
molding was carried out in the same manner as in Example 10, and
evaluations were carried out. The process conditions and the
evaluation results are shown in Table 2.
[0475] It is clear from Examples 17 and 18 that even when the fiber
contents of the molding materials are 10 wt % and 30 wt %, the poly
(phenylene ether ether ketone) oligomer (B) excellently impregnates
into a continuous reinforcing fiber bundle (A), and a molding
material is easily produced. In the molding material obtained, the
poly (phenylene ether ether ketone) oligomer (B) was polymerized
into a poly (phenylene ether ether ketone) (B'), and the molded
article obtained by using this molding material had excellent
dynamic properties.
TABLE-US-00002 TABLE 2 Comparative Comparative Example 10 Example
11 Example 4 Example 12 Example 13 Example 14 Example 5
(Composition) Component (A): Carbon fiber wt % 20 20 20 20 20 20 20
Component (B): Poly (phenylene Type Reference Reference Reference
Reference Reference Reference Reference ether ether ketone)
oligomer Example 1 Example 2 Example 3 Example 4 Example 1 Example
1 Example 1 wt % 5 5 5 5 18 30 30 Component (C): Thermoplastic Type
PEEK PEEK PEEK PEEK PEEK PEEK PEEK resin wt % 75 75 75 75 62 50 50
Component (D): Polymerization Type CsF CsF CsF CsF CsF CsF --
catalyst mol % 5 5 5 5 5 5 (Properties of Poly (phenylene ether
ether ketone) (B')) Melting point .degree. C. 347 349 334 349 348
350 278 Fusion enthalpy J/g 54 51 30 53 55 56 -- Reduced viscosity
dL/g 0.5 0.5 0.6 0.5 0.5 0.5 -- (Process conditions) Molten bath
temperarute .degree. C. 230 230 350 230 230 230 230 Roll
temperature .degree. C. 230 230 350 230 230 230 230 Furnace
temperature .degree. C. 300 300 350 300 300 300 300 Furnace
residence time min 30 30 30 30 30 30 30 Extrusion temperature
.degree. C. 400 400 400 400 400 400 400 Injection-molding
temperature .degree. C. 400 400 400 400 400 400 400 Mold
temperature .degree. C. 160 160 160 160 160 160 160 (Productivity
of molding material) Productivity evaluation of -- good good bad
good good good good molding material (Properties of Moled article)
Number-average fiber length mm 0.45 0.45 -- 0.40 0.45 0.45 0.55
Weight-average fiber length mm 0.65 0.60 -- 0.65 0.65 0.65 0.75
Density g/cm.sup.3 1.37 1.37 -- 1.37 1.37 1.37 1.37 Flexural
modulus GPa 15 15 -- 15 15 15 13 Flexural strength MPa 270 270 --
275 265 260 130 Izod impact J/m 120 120 -- 115 110 110 30
Comparative Example 6 Example 15 Example 16 Example 17 Example 18
(Composition) Component (A): Carbon fiber wt % 20 20 20 10 30
Component (B): Poly (phenylene Type -- Reference Reference
Reference Reference ether ether ketone) oligomer Example 1 Example
1 Example 1 Example 1 wt % 5 5 3 15 Component (C): Thermoplastic
Type PEEK PEEK PEEK PEEK PEEK resin wt % 80 75 75 87 55 Component
(D): Polymerization Type -- CsF CsF CsF CsF catalyst mol % 5 5 5 5
(Properties of Poly (phenylene ether ether ketone) (B')) Melting
point .degree. C. -- 332 330 347 347 Fusion enthalpy J/g -- 38 36
54 54 Reduced viscosity dL/g -- 0.6 0.7 0.5 0.5 (Process
conditions) Molten bath temperarute .degree. C. -- 230 230 230 230
Roll temperature .degree. C. 230 230 230 230 230 Furnace
temperature .degree. C. 230 350 400 300 300 Furnace residence time
min 30 10 10 30 30 Extrusion temperature .degree. C. 400 400 400
400 400 Injection-molding temperature .degree. C. 400 400 400 400
400 Mold temperature .degree. C. 160 160 160 160 160 (Productivity
of molding material) Productivity evaluation of -- bad fair fair
good good molding material (Properties of Moled article)
Number-average fiber length mm -- 0.40 0.40 0.60 0.40
Weight-average fiber length mm -- 0.60 0.55 0.75 0.55 Density
g/cm.sup.3 -- 1.37 1.37 1.34 1.41 Flexural modulus GPa -- 15 15 10
20 Flexural strength MPa -- 275 280 210 335 Izod impact J/m -- 120
125 95 140
Example 19
[0476] To the poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1, cesium fluoride was added as a
polymerization catalyst (D) in an amount of 5 mol % based on the
repeating unit of the formula: --(O-Ph-O-Ph-CO-Ph)-, which is a
main structural unit of the poly (phenylene ether ether ketone)
oligomer (B), and the resulting mixture was melted in a molten bath
at 230.degree. C. to obtain a molten mixture. Using a knife coater,
the molten mixture was applied to release paper to a given
thickness at 230.degree. C. to produce a resin film.
[0477] Next, two resin films were laminated on both surfaces of
carbon fibers "TORAYCA" (registered trademark) T700S-24K (available
from TORAY INDUSTRIES, INC.) which was unidirectionally arranged in
the form of a sheet, and using rolls heated to 230.degree. C., the
carbon fibers were impregnated with the molten mixture by applying
a roll pressure of 0.2 MPa to prepare a unidirectional prepreg. The
unidirectional prepreg obtained was cut to a predetermined size,
and evaluation of the content of the reinforcing fiber substrate
(A'), evaluation of the impregnation rate of the poly (phenylene
ether ether ketone) oligomer (B), and evaluation of the drape
property of a molding material were carried out.
[0478] The unidirectional prepregs obtained were aligned in the
fiber direction and laminated such that a molded article has a
thickness of 2.+-.0.4 mm, and then hot-pressed using a press
molding machine at a mold surface temperature of 300.degree. C.
under a molding pressure of 0.5 MPa for a heating time of 30
minutes to convert the poly (phenylene ether ether ketone) oligomer
(B) into a poly (phenylene ether ether ketone) (B'). Soon after the
hot-pressing, the press molding machine was opened, and the molded
article was demolded to obtain a laminated plate using the molding
material of the present invention. The poly (phenylene ether ether
ketone) (B') was physically separated from the laminated plate
obtained here and subjected to melting point measurement, melting
enthalpy measurement, and viscosity measurement. Further, the
laminated plate obtained was cut to a predetermined size and
subjected to flexural test and void fraction evaluation of the
molded article. In the flexural test of the molded article, the
molding materials were laminated in unidirectional alignment in the
fiber direction, and a test piece having a size in accordance with
JIS K 7074-1988 was cut out from the molded article having a
thickness of 2.+-.0.4 mm with the fiber axis direction as the long
side. "INSTRON" (registered trademark) universal tester Model 4201
(manufactured by INSTRON) was used as a tester, and a 3-point
flexural test was performed to determine the 0.degree. flexural
modulus and 0.degree. flexural strength. The process conditions and
the evaluation results are shown in Table 3.
Example 20
[0479] A unidirectional prepreg was prepared in the same manner as
in Example 19 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 2 was used. Using the
unidirectional prepreg obtained, evaluations of the molding
material were carried out in the same manner as in Example 19.
[0480] Using the unidirectional prepreg obtained, press molding was
carried out in the same manner as in Example 19, and the laminated
plate obtained was evaluated. The process conditions and the
evaluation results are shown in Table 3.
Comparative Example 7
[0481] Production of a unidirectional prepreg was attempted in the
same manner as in Example 19 except that the poly (phenylene ether
ether ketone) oligomer (B) prepared in Reference Example 3 was
used; the resin melting temperature, the film-forming temperature,
and the fiber impregnation temperature were changed to 350.degree.
C.; and the roll pressure for fiber impregnation was changed to 0.5
MPa, but the resin did not impregnate into the reinforcing fiber
substrate (A'). This was because due to high process temperature,
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) into a poly (phenylene ether ether ketone) (B') proceeded, and
impregnation into the reinforcing fiber substrate (A') became
difficult. Using the unidirectional prepreg obtained, evaluations
of the molding material were carried out in the same manner as in
Example 19.
[0482] Press molding was carried out in the same manner as in
Example 19 except that the unidirectional prepreg obtained was
hot-pressed at a mold surface temperature of 400.degree. C. and
then the mold was cooled to 150.degree. C. at 10.degree. C./min
before demolding a molded article. The laminated plate obtained was
evaluated. The process conditions and the evaluation results are
shown in Table 3.
Example 21
[0483] A unidirectional prepreg was prepared in the same manner as
in Example 19 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 4 was used. Using the
unidirectional prepreg obtained, evaluations of the molding
material were carried out in the same manner as in Example 19.
[0484] Using the unidirectional prepreg obtained, press molding was
carried out in the same manner as in Example 19, and the laminated
plate obtained was evaluated. The process conditions and the
evaluation results are shown in Table 3.
[0485] It is clear from the results of Examples 19 to 21 that
regardless of the method for producing a poly (phenylene ether
ether ketone) oligomer (B), by using a poly (phenylene ether ether
ketone) oligomer (B) having a melting point of not higher than
270.degree. C., the poly (phenylene ether ether ketone) oligomer
(B) excellently impregnates into a reinforcing fiber substrate
(A'), and a molding material can be easily produced. In the molding
material obtained, the poly (phenylene ether ether ketone) oligomer
(B) was polymerized into a poly (phenylene ether ether ketone)
(B'), and the molded article obtained by using this molding
material had excellent dynamic properties.
[0486] It is clear from Comparative Example 7 that when a poly
(phenylene ether ether ketone) composition having a melting point
of higher than 270.degree. C. is used, it is necessary to set the
process temperature high, and polymerization of the poly (phenylene
ether ether ketone) composition proceeds in the molten bath or the
like, resulting in significantly reduced impregnation into the
reinforcing fiber substrate (A'). Further, it is clear that since
it is necessary to set the process temperature high, this molding
material is inferior in terms of economic efficiency, and the
resulting molded article also has poor dynamic properties.
Comparative Example 8
[0487] A unidirectional prepreg was prepared in the same manner as
in Example 19 except that cesium fluoride serving as a
polymerization catalyst (D) was not used. Using the unidirectional
prepreg obtained, evaluations of the molding material were carried
out in the same manner as in Example 19.
[0488] Press molding was carried out in the same manner as in
Example 19 except that the unidirectional prepreg obtained was
hot-pressed with a pressing machine and then the mold was cooled to
150.degree. C. at 10.degree. C./min before demolding a molded
article. The laminated plate obtained was subjected to melting
point measurement, and it was found that the melting point remained
as low as 276.degree. C. The process conditions and the evaluation
results are shown in Table 3.
[0489] It is clear from Comparative Example 8 that in the molding
material to which a polymerization catalyst (D) is not added,
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) into a poly (phenylene ether ether ketone) (B') does not
proceed during molding.
Comparative Example 9
[0490] Production of a unidirectional prepreg was attempted in the
same manner as in Example 19 except that VICTREX "PEEK" (registered
trademark) 151G (polyether ether ketone resin available from
Victrex-MC, Inc., melting point: 343.degree. C.) was used in place
of the poly (phenylene ether ether ketone) oligomer (B); the resin
melting temperature, the film-forming temperature, and the fiber
impregnation temperature were changed to 400.degree. C.; and the
roll pressure for fiber impregnation was changed to 0.5 MPa, but
the resin was highly viscous and did not impregnate into the
reinforcing fiber substrate (A'). Using the unidirectional prepreg
obtained, evaluations of the molding material were carried out in
the same manner as in Example 19.
[0491] The unidirectional prepreg obtained was press-molded in the
same manner as in Comparative Example 7, and the laminated plate
obtained was evaluated. The process conditions and the evaluation
results are shown in Table 3.
[0492] It is clear from Comparative Example 9 that when a
high-molecular-weight polyether ether ketone resin is used,
impregnation into a reinforcing fiber substrate (A') is difficult,
and the productivity of the molding material is poor. It is clear
that since it is necessary to set the process temperature high,
this molding material is inferior in terms of economic efficiency,
and the resulting molded article also has poor dynamic
properties.
Example 22
[0493] A unidirectional prepreg was prepared in the same manner as
in Example 19, and evaluations of the molding material were carried
out.
[0494] Press molding was carried out in the same manner as in
Example 19 except that the unidirectional prepreg obtained was
hot-pressed at a mold surface temperature of 350.degree. C. for a
heating time of 10 minutes and then the mold was cooled to
150.degree. C. at 10.degree. C./min before demolding a molded
article. The laminated plate obtained was evaluated. The process
conditions and the evaluation results are shown in Table 3.
Example 23
[0495] A unidirectional prepreg was prepared in the same manner as
in Example 19, and evaluations of the molding material were carried
out.
[0496] Press molding was carried out in the same manner as in
Example 19 except that the unidirectional prepreg obtained was
hot-pressed at a mold surface temperature of 400.degree. C. for a
heating time of 10 minutes and then the mold was cooled to
150.degree. C. at 10.degree. C./min before demolding a molded
article. The laminated plate obtained was evaluated. The process
conditions and the evaluation results are shown in Table 3.
[0497] Examples 22 and 23 show that the molded articles obtained by
the molding method in which molding is carried out at a mold
surface temperatures of 350.degree. C. and 400.degree. C. and
molded articles are demolded after the mold is cooled had excellent
dynamic properties. Also in these molded articles, the poly
(phenylene ether ether ketone) oligomer (B) was polymerized into a
poly (phenylene ether ether ketone) (B'). Further, the poly
(phenylene ether ether ketone) (B') in the molding material
produced under these conditions had a melting enthalpy of less than
40 kJ/g, which was equivalent to that of known poly (phenylene
ether ether ketone).
Example 24
[0498] A unidirectional prepreg was prepared in the same manner as
in Example 19 except that the supply of raw materials was adjusted
such that the content of the reinforcing fiber substrate (A') was
76 wt %. Using the unidirectional prepreg obtained, evaluations of
the molding material were carried out in the same manner as in
Example 19.
[0499] Using the unidirectional prepreg obtained, press molding was
carried out in the same manner as in Example 19, and the laminated
plate obtained was evaluated. The process conditions and the
evaluation results are shown in Table 3.
[0500] It is clear from Example 24 that even when the content of
the reinforcing fibers (A) is 76 wt %, the productivity of the
molding material is excellent, and the resulting molded article has
excellent dynamic properties.
Example 25
[0501] To the poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1, cesium fluoride was added as a
polymerization catalyst (D) in an amount of 5 mol % based on the
repeating unit of the formula: --(O-Ph-O-Ph-CO-Ph)-, which is a
main structural unit of the poly (phenylene ether ether ketone)
oligomer (B), and the resulting mixture was melted in a molten bath
at 230.degree. C. to obtain a molten mixture. Using a knife coater,
the molten mixture was applied to release paper to a given
thickness at 230.degree. C. to produce a resin film.
[0502] Next, two resin films were laminated on both surfaces of
carbon fibers "TORAYCA" (registered trademark) T700S-24K (available
from TORAY INDUSTRIES, INC.) which was unidirectionally arranged in
the form of a sheet, and using rolls heated to 230.degree. C., the
carbon fibers were impregnated with the molten mixture at a roll
pressure of 0 MPa to prepare a unidirectional prepreg. The
unidirectional prepreg obtained was cut to a predetermined size,
and evaluation of the content of the reinforcing fiber substrate
(A'), evaluation of the impregnation rate of the poly (phenylene
ether ether ketone) oligomer (B), and evaluation of the drape
property of a molding material were carried out.
[0503] The unidirectional prepregs obtained were aligned in the
fiber direction and laminated such that a molded article has a
thickness of 2.+-.0.4 mm, and then hot-pressed using a press
molding machine at a mold surface temperature of 300.degree. C.
under a molding pressure of 0.5 MPa for a heating time of 30
minutes to convert the poly (phenylene ether ether ketone) oligomer
(B) into a poly (phenylene ether ether ketone) (B'). Soon after the
hot-pressing, the press molding machine was opened, and the molded
article was demolded to obtain a laminated plate using the molding
material of the present invention. The poly (phenylene ether ether
ketone) (B') was physically separated from the laminated plate
obtained here and subjected to melting point measurement, melting
enthalpy measurement, and viscosity measurement. Further, the
laminated plate obtained was subjected to a flexural test in
accordance with JIS K 7074-1988 and void fraction evaluation of the
molded article. The process conditions and the evaluation results
are shown in Table 3.
Example 26
[0504] A unidirectional prepreg was prepared in the same manner as
in Example 25, and evaluations of the molding material were carried
out.
[0505] Press molding was carried out in the same manner as in
Example 25 except that the unidirectional prepreg obtained was
hot-pressed at a mold surface temperature of 400.degree. C. for a
heating time of 10 minutes and then the mold was cooled to
150.degree. C. at 10.degree. C./min before demolding a molded
article. The laminated plate obtained was evaluated. The process
conditions and the evaluation results are shown in Table 3.
Comparative Example 10
[0506] A unidirectional prepreg was prepared in the same manner as
in Example 25, and evaluations of the molding material were carried
out.
[0507] The unidirectional prepreg obtained was press-molded in the
same manner as in Example 25 except that the mold surface
temperature was changed to 400.degree. C. and the heating time was
changed to 10 minutes. However, the lamination was peeled off at
demolding, and a sound molded article could not be obtained.
[0508] Examples 25 and 26 show that the molding materials having an
impregnation rate of the poly (phenylene ether ether ketone)
oligomer (B) of 20% to less than 80% had excellent drape property;
the poly (phenylene ether ether ketone) oligomer (B) were
polymerized into a poly (phenylene ether ether ketone) (B') in the
molding material obtained; and the molded article obtained by using
this molding material had excellent dynamic properties.
[0509] It can be seen from Comparative Example 10 that when molding
is carried out at a mold surface temperature of 400.degree. C. and
a molded article is demolded without cooling the mold, the
lamination is peeled off, and a sound molded article cannot be
obtained.
TABLE-US-00003 TABLE 3 Comparative Comparative Comparative Example
Example 19 Example 20 Example 7 Example 21 Example 8 Example 9 22
(Composition) Component (B): Poly (phenylene Type Reference
Reference Reference Reference Reference High molecular Reference
ether ether ketone) oligomer Example 1 Example 2 Example 3 Example
4 Example 1 weight PEEK Example 1 wt % 100 100 100 100 100 100 100
Component (D): Polymerization Type CsF CsF CsF CsF -- -- CsF
catalyst mol % 5 5 5 5 5 (Producing conditions of Molding material)
Resin melting temperature .degree. C. 230 230 350 230 230 400 230
Film formation temperature .degree. C. 230 230 350 230 230 400 230
Fiber impregnation temperature .degree. C. 230 230 350 230 230 400
230 Fiber impregnation roll MPa 0.2 0.2 0.5 0.2 0.2 0.5 0.2
pressure (Properties of Molding material) Component (A') content wt
% 64 64 64 64 64 64 64 Impregnation rate of Component -- good good
bad good good bad good (B) Drape property -- fair fair good fair
fair good fair (Molding conditions using Molding material) Mold
surface temperature .degree. C. 300 300 400 300 300 400 350 Molding
pressure MPa 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Heating time min 30 30 30
30 30 30 1.0 Mold cooling time min -- -- 25 -- 15 25 20 (Properties
of Poly (phenylene ether ether ketone) (B')) Melting point .degree.
C. 347 346 335 344 276 343 330 Fusion enthalpy J/g 33 52 32 53 --
-- 36 Reduced viscosity dL/g 0.5 0.5 0.6 0.5 -- -- 0.6 (Properties
of Moled article) Flexural modulus at 0.degree. GPa 120 120 100 120
-- 95 120 Flexural strength at 0.degree. MPa 1700 1750 1100 1700 --
1000 1650 Void ratio of Molded article -- good good bad good -- bad
good Comparative Example 23 Example 24 Example 25 Example 26
Example 10 (Composition) Component (B): Poly (phenylene Type
Reference Reference Reference Reference Reference ether ether
ketone) oligomer Example 1 Example 1 Example 1 Example 1 Example 1
wt % 100 100 100 100 100 Component (D): Polymerization Type CsF CsF
CsF CsF CsF catalyst mol % 5 5 5 5 5 (Producing conditions of
Molding material) Resin melting temperature .degree. C. 230 230 230
230 230 Film formation temperature .degree. C. 230 230 230 230 230
Fiber impregnation temperature .degree. C. 230 230 230 230 230
Fiber impregnation roll MPa 0.2 0.2 0 0 0 pressure (Properties of
Molding material) Component (A') content wt % 64 76 64 64 64
Impregnation rate of Component -- good good fair fair fair (B)
Drape property -- fair bad excellent excellent excellent (Molding
conditions using Molding material) Mold surface temperature
.degree. C. 400 300 300 400 400 Molding pressure MPa 0.5 0.5 0.5
0.5 0.5 Heating time min 10 30 30 10 10 Mold cooling time min 25 --
-- 25 -- (Properties of Poly (phenylene ether ether ketone) (B'))
Melting point .degree. C. 329 347 346 330 330 Fusion enthalpy J/g
38 54 54 36 36 Reduced viscosity dL/g 0.7 0.5 0.5 0.7 0.7
(Properties of Moled article) Flexural modulus at 0.degree. GPa 120
140 120 120 -- Flexural strength at 0.degree. MPa 1700 2000 1550
1600 -- Void ratio of Molded article -- good good fair fair --
Example 27
[0510] A method for producing a molding material will be described
with reference to the apparatus shown in FIG. 13. The apparatus
configuration used in this production method is defined as
(E1).
[0511] Step (I):
[0512] A plurality of carbon fibers "TORAYCA" (registered
trademark) T700S-12K (available from TORAY INDUSTRIES, INC.) are
aligned in a width of 100 mm such that the gaps in a reinforcing
fiber bundle are 1 to 5 mm and supplied to a production line. The
reinforcing fiber bundle is placed on a roll bar 11, arranged in
the form of a sheet, fed to an impregnation bath 12, passed through
rotating rollers 13 in the impregnation bath, passed through a
hot-air drying furnace 14, further passed through a double belt
press 15, a heating chamber 25, and a hot roller 27 in the order
mentioned, and taken up by applying a tension with a nip roller 16.
The take-up speed is set at 3 m/min, and after the operation is
stabilized, the reinforcing fiber bundle is heated to 150.degree.
C. with an infrared heater 17 for preheating.
[0513] Step (II):
[0514] The poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1 with a given amount of a
polymerization catalyst (D) added was made into a dispersion, which
was fed to an impregnation bath via a pump 18. Through the
immersion of the rotating rollers into the dispersion, the
reinforcing fiber bundle is provided with the poly (phenylene ether
ether ketone) oligomer (B) and the polymerization catalyst (D). For
the amount of the poly (phenylene ether ether ketone) oligomer (B)
and the polymerization catalyst (D) deposited through the
immersion, the length of time for immersing the reinforcing fiber
bundle is adjusted such that the fiber content by weight (Wf) is
64%. Further, 90% or more of moisture was removed from the
reinforcing fiber bundle by adjusting the temperature in the
hot-air drying furnace 14 to 140.degree. C. to obtain a composite
of the reinforcing fiber substrate (A'), the poly (phenylene ether
ether ketone) oligomer (B), and the polymerization catalyst
(D).
[0515] Using the double belt press having a length of 4 m in the
line direction under the conditions of a temperature of 230.degree.
C. and a pressure of 3 MPa, the composite was passed therethrough
while being hot-pressed to heat-impregnate the poly (phenylene
ether ether ketone) oligomer (B) into the reinforcing fiber
substrate (A'), thereby obtaining an impregnated body comprising
the reinforcing fiber substrate (A'), the poly (phenylene ether
ether ketone) oligomer (B), and the polymerization catalyst (D). At
this time, nitrogen was purged through an inlet port 20 of a
chamber 19 housing the double belt press to adjust the oxygen
concentration in the chamber to 1% by volume or less.
[0516] Step (III):
[0517] Using the heating chamber 25 having a length of 30 m in the
line direction under the conditions of a temperature of 400.degree.
C., the impregnated body is passed therethrough while being heated
to polymerize the poly (phenylene ether ether ketone) oligomer (B).
Further, using the hot roller 27, the resultant was molded under
the conditions of 400.degree. C. and a pressure of 1 MPa to obtain
a polymer comprising the reinforcing fiber substrate (A'), the poly
(phenylene ether ether ketone) (B'), and the polymerization
catalyst (D). At this time, nitrogen was purged through an inlet
port 26 of the heating chamber 25 to adjust the oxygen
concentration in the chamber to 1% by volume or less.
[0518] Step (IV):
[0519] The polymer was passed over a cooling plate 21 at 50.degree.
C. to solidify the poly (phenylene ether ether ketone) (B'), taken
up with a nip roll, and then cut with a guillotine cutter 22 at 1-m
intervals to prepare a sheet-like molding material with a width of
100 mm.
[0520] The above steps were all performed on-line to continuously
produce a molding material. The poly (phenylene ether ether ketone)
(B') was physically separated from the molding material obtained
and subjected to melting point measurement, melting enthalpy
measurement, and viscosity measurement.
[0521] The molding materials obtained were aligned in the fiber
direction and laminated such that a molded article has a thickness
of 2.+-.0.4 mm, and then hot-pressed using a press molding machine
at a mold surface temperature of 400.degree. C. under a molding
pressure of 3 MPa for 3 minutes. Thereafter, the mold was cooled,
and the molded article was demolded to obtain a laminated plate. A
test piece having a size in accordance with JIS K 7074-1988 was cut
out from the laminated plate obtained with the fiber axis direction
as the long side, and a 3-point flexural test was performed using
"INSTRON" (registered trademark) universal tester Model 4201
(manufactured by INSTRON) as a tester to determine the 0.degree.
flexural modulus and 0.degree. flexural strength. The process
conditions and the evaluation results are shown in Table 4.
Example 28
[0522] A molding material was produced in the same manner as in
Example 27 except that the heating chamber temperature in the step
(III) was changed to 300.degree. C. and the take-up speed of the
reinforcing fiber substrate (A') was changed to 1 m/min. The
molding material obtained was evaluated in the same manner as in
Example 27. The molding material obtained here was characterized in
that the melting point of the poly (phenylene ether ether ketone)
(B') and the melting enthalpy were high compared to Example 27. The
process conditions and the evaluation results are shown in Table
4.
Comparative Example 11
[0523] A molding material was produced in the same manner as in
Example 27 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 3 was used. The molding
material obtained was evaluated in the same manner as in Example
27. The molding material obtained here was characterized in that
the impregnation rate of the poly (phenylene ether ether ketone)
(B') was low; the resulting molded article had many voids; and the
dynamic properties were poor, as compared to Example 27. This is
probably because the poly (phenylene ether ether ketone) oligomer
(B) was poorly impregnated into a reinforcing fiber substrate (A').
The process conditions and the evaluation results are shown in
Table 4.
Comparative Example 12
[0524] A molding material was produced in the same manner as in
Comparative Example 11 except that the temperature of the double
belt press in the step (II) was changed to 350.degree. C. The
molding material obtained was evaluated in the same manner as in
Example 27. Although the molding material obtained here had a
relatively high impregnation rate of the poly (phenylene ether
ether ketone) (B'), the high temperature in the impregnation
process imposed a heavy load on the apparatus, and thus this method
was not economically preferred. The process conditions and the
evaluation results are shown in Table 4.
Comparative Example 13
[0525] A molding material was produced in the same manner as in
Example 27 except that VICTREX "PEEK" (registered trademark) 151G
(polyether ether ketone resin available from Victrex-MC, Inc.,
melting point: 343.degree. C.) was used in place of the poly
(phenylene ether ether ketone) oligomer (B), and the temperature of
the double belt press in the step (II) was changed to 400.degree.
C. The molding material obtained was evaluated in the same manner
as in Example 27. The molding material obtained here was
characterized in that the impregnation rate of the poly (phenylene
ether ether ketone) (B') was low; the resulting molded article had
many voids; and the dynamic properties were poor, as compared to
Example 27. Further, the high temperature in the impregnation
process imposed a heavy load on the apparatus, and thus this method
was not economically preferred. The process conditions and the
evaluation results are shown in Table 4.
TABLE-US-00004 TABLE 4 Comparative Comparative Comparative Example
27 Example 28 Example 11 Example 12 Example 13 (Composition)
Component (A'): Reinforcing wt % 64 64 64 64 64 fiber substrate
Component (B): Poly (phenylene Type Reference Reference Reference
Reference High molecular ether ether ketone) oligomer Example 1
Example 1 Example 3 Example 3 weight PEEK wt % 36 36 36 36 36
Component (D): Polymerization Type CsF CsF CsF CsF -- catalyst mol
% 5 5 5 5 (Producing conditions of Molding material) Constitution
of the apparatus -- (E1) (E1) (E1) (E1) (E1) <Step (I)>
Preheating temperature .degree. C. 150 150 150 150 150 <Step
(II)> Heat dry oven temperature .degree. C. 140 140 140 140 140
Double belt press temperature .degree. C. 230 230 230 350 400
Double belt press pressure MPa 3 3 3 3 3 <Step (III)> Heating
chamber temperature .degree. C. 400 300 400 400 400 Heating time
min 10 30 10 10 10 <Step (IV)> Taking up speed m/min 3 1 3 3
3 (Properties of Molding material) Impregnation rate of Component
-- good good bad fair bad (B') <Properties of Poly (phenylene
ether ether ketone) (B')> Melting point .degree. C. 328 346 335
325 343 Fusion enthalpy J/g 39 55 31 35 -- Reduced viscosity dL/g
0.7 0.5 0.6 0.7 -- (Molding conditions using Molding material) Mold
surface temperature .degree. C. 400 400 400 400 400 Molding
pressure MPa 3 3 3 3 3 Heating time min 3 3 3 3 3 (Properties of
Moled article) Flexural modulus at 0.degree. GPa 120 120 90 110 95
Flexural strength at 0.degree. MPa 1650 1700 1000 1400 950 Void
ratio of Molded article -- good good bad fair bad
[0526] Examples and Comparative Examples in Table 4 reveal the
following. It is clear that because the methods for producing a
molding material in Examples 27 and 28 use the poly (phenylene
ether ether ketone) oligomer (B) in the present invention, they are
superior to the methods in Comparative Examples 11 to 13 in terms
of the process temperature and impregnation properties in the
production of a molding material, and the molded article obtained
by using this molding material has excellent dynamic
properties.
Example 29
[0527] A method for producing a molding material will be described
with reference to the apparatus shown in FIG. 14. The apparatus
configuration used in this production method is defined as
(E2).
[0528] Step (I):
[0529] A plurality of carbon fibers "TORAYCA" (registered
trademark) T700S-12K (available from TORAY INDUSTRIES, INC.) are
aligned in a width of 100 mm such that the gaps in a reinforcing
fiber bundle are 1 to 5 mm and supplied to a production line. The
reinforcing fiber bundle is placed on a roll bar 31, arranged in
the form of a sheet, fed to a belt conveyor 32, further sandwiched
between a pair of hot rollers 33, and taken up around a drum winder
35 by applying a tension with a nip roller 34. The take-up speed is
set at 5 m/min, and after the operation is stabilized, the
reinforcing fiber bundle is heated to 150.degree. C. with an
infrared heater 36 for preheating.
[0530] Step (II):
[0531] The mixture of a poly (phenylene ether ether ketone)
oligomer (B) and a polymerization catalyst (D) prepared in
Reference Example 1 was melted at 230.degree. C., and the melt
obtained was applied to release paper to a given thickness using a
knife coater to produce a film. The film was mounted on a draw
winder 37, and supplied together with the release paper to a hot
roller 38 under the conditions of 230.degree. C. and 1 MPa to
heat-impregnate the poly (phenylene ether ether ketone) oligomer
(B) into a reinforcing fiber substrate (A'), thereby obtaining an
impregnated body comprising the reinforcing fiber substrate (A'),
the poly (phenylene ether ether ketone) oligomer (B), and the
polymerization catalyst (D). The release paper was removed by
taking it up with a take-up winder 39. The amount of the poly
(phenylene ether ether ketone) oligomer (B) deposited was measured
to show that the fiber content by weight (Wf) was 64%.
[0532] Step (III):
[0533] The temperature in a heating chamber 40 having a length of
50 m in the line direction was set at 400.degree. C., and the hot
rollers 33 was set at a pressure of 0.1 MPa, under which conditions
the impregnated body was passed therethrough, and the poly
(phenylene ether ether ketone) oligomer (B) was polymerized to
obtain a polymer. At this time, nitrogen was purged through an
inlet port 41 of the heating chamber 40 to adjust the oxygen
concentration in the heating chamber to 1% by volume or less.
[0534] Step (IV):
[0535] The polymer was passed over a cooling plate 42 at 50.degree.
C. to solidify the poly (phenylene ether ether ketone) (B'), taken
up with a nip roll, and then taken up around the drum winder to
prepare a molding material with a width of 100 mm.
[0536] The above steps were all performed on-line to continuously
produce a molding material. The poly (phenylene ether ether ketone)
(B') was physically separated from the molding material obtained
and subjected to melting point measurement, melting enthalpy
measurement, and viscosity measurement.
[0537] The molding materials obtained were aligned in the fiber
direction and laminated such that a molded article has a thickness
of 2.+-.0.4 mm, and then hot-pressed using a press molding machine
at a mold surface temperature of 400.degree. C. under a molding
pressure of 3 MPa for 3 minutes. Thereafter, the mold was cooled,
and the molded article was demolded to obtain a laminated plate. A
test piece having a size in accordance with JIS K 7074-1988 was cut
out from the laminated plate obtained with the fiber axis direction
as the long side, and a 3-point flexural test was performed using
"INSTRON" (registered trademark) universal tester Model 4201
(manufactured by INSTRON) as a tester to determine the 0.degree.
flexural modulus and 0.degree. flexural strength. The process
conditions and the evaluation results are shown in Table 5.
Example 30
[0538] A molding material was produced in the same manner as in
Example 29 except that the heating chamber temperature in the step
(III) was changed to 300.degree. C. and the take-up speed of the
reinforcing fiber substrate (A') was changed to 1.7 m/min. The
molding material obtained was evaluated in the same manner as in
Example 29. The molding material obtained here was characterized in
that the melting point of the poly (phenylene ether ether ketone)
(B') and the melting enthalpy were high compared to Example 29. The
process conditions and the evaluation results are shown in Table
5.
Comparative Example 14
[0539] A molding material was produced in the same manner as in
Example 29 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 3 was used and that the
film-forming temperature and hot roller temperature in the step
(II) were changed to 350.degree. C. The molding material obtained
was evaluated in the same manner as in Example 29. The molding
material obtained here was characterized in that the impregnation
rate of the poly (phenylene ether ether ketone) (B') was low; the
resulting molded article had many voids; and the dynamic properties
were poor, as compared to Example 29. This is probably because the
poly (phenylene ether ether ketone) oligomer (B) was polymerized at
the film-formation and poorly impregnated into a reinforcing fiber
substrate (A'). The process conditions and the evaluation results
are shown in Table 5.
Comparative Example 15
[0540] A molding material was produced in the same manner as in
Example 29 except that VICTREX "PEEK" (registered trademark) 151G
(polyether ether ketone resin available from Victrex-MC, Inc.,
melting point: 343.degree. C.) was used in place of the poly
(phenylene ether ether ketone) oligomer (B) and that the
film-forming temperature and hot roller temperature in the step
(II) were changed to 400.degree. C. The molding material obtained
was evaluated in the same manner as in Example 29. The molding
material obtained here was characterized in that the impregnation
rate of the poly (phenylene ether ether ketone) (B') was low; the
resulting molded article had many voids; and the dynamic properties
were poor, as compared to Example 29. The process conditions and
the evaluation results are shown in Table 5.
TABLE-US-00005 TABLE 5 Comparative Comparative Example 29 Example
30 Example 14 Example 15 (Composition) Component (A'): Reinforcing
wt % 64 64 64 64 fiber substrate Component (B): Poly (phenylene
Type Reference Reference Reference High molecular ether ether
ketone) oligomer Example 1 Example 1 Example 3 weight PEEK wt % 36
36 36 36 Component (D): Polymerization Type CsF CsF CsF -- catalyst
mol % 5 5 5 (Producing conditions of Molding material) Constitution
of the apparatus -- (E2) (E2) (E2) (E2) <Step (I)> Preheating
temperature .degree. C. 150 150 150 150 <Step (II)> Film
formation temperature .degree. C. 230 230 350 400 Hot roller
temperature .degree. C. 230 230 350 400 Hot roller pressure MPa 1 1
1 1 <Step (III)> Heating chamber temperature .degree. C. 400
300 400 400 Heating time min 10 30 10 10 Hot roller pressure MPa
0.1 0.1 0.1 0.1 <Step (IV)> Taking up speed m/min 5 1.7 5 5
(Properties of Molding material) Impregnation rate of Component
(B') -- good good bad bad <Properties of Poly (phenylene ether
ether ketone) (B')> Melting point .degree. C. 329 347 335 343
Fusion enthalpy J/g 38 52 32 -- Reduced viscosity dL/g 0.7 0.5 0.6
-- (Molding conditions using Molding material) Mold surface
temperature .degree. C. 400 400 400 400 Molding pressure MPa 3 3 3
3 Heating time min 3 3 3 3 (Properties of Moled article) Flexural
modulus at 0.degree. GPa 120 120 100 95 Flexural strength at
0.degree. MPa 1600 1650 1050 1000 Void ratio of Molded article --
good good bad bad
[0541] Examples and Comparative Examples in Table 5 reveal the
following. It is clear that because the methods for producing a
molding material in Examples 29 and 30 use the poly (phenylene
ether ether ketone) oligomer (B) in the present invention, they are
superior to the methods in Comparative Examples 14 and 15 in terms
of the process temperature and impregnation properties in the
production of a molding material, and the molded article obtained
by using this molding material has excellent dynamic
properties.
Example 31
[0542] A method for producing a molding material will be described
with reference to the apparatus shown in FIG. 15. The apparatus
configuration used in this production method is defined as
(E3).
[0543] Step (I):
[0544] A plurality of carbon fibers "TORAYCA" (registered
trademark) T700S-12K (available from TORAY INDUSTRIES, INC.) are
aligned in a width of 100 mm such that the gaps in a reinforcing
fiber bundle are 1 to 5 mm and supplied to a production line. The
reinforcing fiber bundle is placed on a roll bar 51, arranged in
the form of a sheet, further fed to a calender roll 52, and taken
up around a drum winder 54 by applying a tension with a nip roller
53. The take-up speed is set at 10 m/min, and after the operation
is stabilized, the reinforcing fiber bundle is heated to
150.degree. C. with an infrared heater 55 for preheating.
[0545] Step (II):
[0546] The poly (phenylene ether ether ketone) oligomer (B)
prepared in Reference Example 1 with a given amount of a
polymerization catalyst (D) added was pulverized into particles.
The particles were sprinkled from a metering powder feeder 56 over
the reinforcing fiber bundle such that the fiber content by weight
(Wf) was 64%, and further heated to a temperature of 230.degree. C.
with an infrared heater 62, thereby obtaining a composite in which
the poly (phenylene ether ether ketone) oligomer (B) and the
polymerization catalyst (D) were fused to a reinforcing fiber
substrate (A').
[0547] Step (III):
[0548] Setting the temperature in a heating chamber 57 at
400.degree. C., the composite was passed through a distance of 100
m in the line direction while applying a tension with a calender
roller 52 to obtain a polymer of the poly (phenylene ether ether
ketone) oligomer (B). At this time, nitrogen was purged through an
inlet port 58 of the heating chamber 57 to adjust the oxygen
concentration in the heating chamber to 1% by volume or less.
[0549] Step (IV):
[0550] The polymer was passed over a cooling plate 59 at 50.degree.
C. to solidify the poly (phenylene ether ether ketone) (B'), taken
up with a nip roll, and then taken up around the drum winder to
prepare a molding material with a width of 100 min.
[0551] The above steps were all performed on-line to continuously
produce a molding material. The poly (phenylene ether ether ketone)
(B') was physically separated from the molding material obtained
and subjected to melting point measurement, melting enthalpy
measurement, and viscosity measurement.
[0552] The molding materials obtained were aligned in the fiber
direction and laminated such that a molded article has a thickness
of 2.+-.0.4 mm, and then hot-pressed using a press molding machine
at a mold surface temperature of 400.degree. C. under a molding
pressure of 3 MPa for 3 minutes. Thereafter, the mold was cooled,
and the molded article was demolded to obtain a laminated plate. A
test piece having a size in accordance with JIS K 7074-1988 was cut
out from the laminated plate obtained with the fiber axis direction
as the long side, and a 3-point flexural test was performed using
"INSTRON" (registered trademark) universal tester Model 4201
(manufactured by INSTRON) as a tester to determine the 0.degree.
flexural modulus and 0.degree. flexural strength. The process
conditions and the evaluation results are shown in Table 6.
Example 32
[0553] A molding material was produced in the same manner as in
Example 31 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 2 was used. The molding
material obtained was evaluated in the same manner as in Example
31. The process conditions and the evaluation results are shown in
Table 6.
Comparative Example 16
[0554] A molding material was produced in the same manner as in
Example 31 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 3 was used and that the
fusion temperature in the step (II) was changed to 350.degree. C.
The molding material obtained was evaluated in the same manner as
in Example 31. The molding material obtained here was characterized
in that the impregnation rate of the poly (phenylene ether ether
ketone) (B') was low; the resulting molded article had many voids;
and the dynamic properties were poor, as compared to Example 31.
This is probably because the poly (phenylene ether ether ketone)
oligomer (B) was polymerized at the fusion and poorly impregnated
into a reinforcing fiber substrate (A'). The process conditions and
the evaluation results are shown in Table 6.
Example 33
[0555] A molding material was produced in the same manner as in
Example 31 except that the poly (phenylene ether ether ketone)
oligomer (B) prepared in Reference Example 4 was used. The molding
material obtained was evaluated in the same manner as in Example
31. The process conditions and the evaluation results are shown in
Table 6.
Comparative Example 17
[0556] A molding material was produced in the same manner as in
Example 31 except that VICTREX "PEEK" (registered trademark) 151G
(polyether ether ketone resin available from Victrex-MC, Inc.,
melting point: 343.degree. C.) was used in place of the poly
(phenylene ether ether ketone) oligomer (B) and that the fusion
temperature in the step (II) was changed to 400.degree. C. The
molding material obtained was evaluated in the same manner as in
Example 31. The molding material obtained here was characterized in
that the impregnation rate of the poly (phenylene ether ether
ketone) (B') was low; the resulting molded article had many voids;
and the dynamic properties were poor, as compared to Examples 31 to
33. The process conditions and the evaluation results are shown in
Table 6.
Example 34
[0557] A molding material was produced in the same manner as in
Example 31 except that the heating chamber temperature in the step
(III) was changed to 350.degree. C. The molding material obtained
was evaluated in the same manner as in Example 31. The process
conditions and the evaluation results are shown in Table 6.
Example 35
[0558] A molding material was produced in the same manner as in
Example 31 except that the heating chamber temperature in the step
(III) was changed to 300.degree. C. and the take-up speed of the
reinforcing fiber substrate (A') was changed to 3.3 m/min. The
molding material obtained was evaluated in the same manner as in
Example 31. The molding material obtained here was characterized in
that the melting point of the poly (phenylene ether ether ketone)
(B') and the melting enthalpy were high compared to Example 31. The
process conditions and the evaluation results are shown in Table
6.
Example 36
[0559] A molding material was produced in the same manner as in
Example 31 except that the content of the reinforcing fiber
substrate (A') was changed to 76 wt % and the content of the poly
(phenylene ether ether ketone) oligomer (B) of Reference Example 1
was changed to 24 wt %. The molding material obtained was evaluated
in the same manner as in Example 31. The process conditions and the
evaluation results are shown in Table 6.
TABLE-US-00006 TABLE 6 Comparative Comparative Example 31 Example
32 Example 16 Example 33 Example 17 Example 34 Example 35 Example
36 (Composition) Component (A'): wt % 64 64 64 64 64 64 64 76
Reinforcing fiber substrate Component (B): Poly Type Reference
Reference Reference Reference High Reference Reference Reference
(phenylene ether ether Example 1 Example 2 Example 3 Example 4
molecular Example 1 Example 1 Example 1 ketone) oligomer weight
PEEK wt % 36 36 36 36 36 36 36 24 Component (D): Poly- Type CsF CsF
CsF CsF -- CsF CsF CsF merization catalyst mol % 5 5 5 5 5 5 5
(Producing conditions of Molding material) Constitution of the --
(E3) (E3) (E3) (E3) (E3) (E3) (E3) (E3) apparatus <Step (I)>
Preheating temperature .degree. C. 150 150 150 150 150 150 150 150
<Step (II)> Fusion step temperature .degree. C. 230 230 350
230 400 230 230 230 <Step (III)> Heating chamber .degree. C.
400 400 400 400 400 350 300 400 temperature Heating time min 10 10
10 10 10 10 30 10 <Step (IV)> Taking up speed m/min 10 10 10
10 10 10 3.3 10 (Properties of Molding material) Impregnation rate
of -- good good bad good bad good good good Component (B')
<Properties of Poly (phenylene ether ether ketone) (B')>
Melting point .degree. C. 330 331 327 332 343 330 347 329 Fusion
enthalpy J/g 38 34 32 36 -- 36 53 36 Reduced viscosity dL/g 07 0.7
0.6 0.7 -- 0.6 0.5 0.7 (Molding conditions using Molding material)
Mold surface temperature .degree. C. 400 400 400 400 400 400 400
400 Molding pressure MPa 3 3 3 3 3 3 3 3 Heating time min 3 3 3 3 3
3 3 3 (Properties of Moled article) Flexural modulus at 0.degree.
GPa 120 120 100 120 90 120 120 140 Flexural strength at 0.degree.
MPa 1600 1650 1050 1650 900 1650 1650 2050 Void ratio of Molded --
good good bad good bad good good good article
[0560] Examples and Comparative Examples in Table 6 reveal the
following. It is clear from the results of Examples 31 to 33 that
regardless of the production method, the poly (phenylene ether
ether ketone) oligomer (B) in the present invention, as compared to
Comparative Examples 16 and 17, is excellent in the process
temperature and impregnation properties in the production of a
molding material, and the molded article obtained by using this
molding material has excellent dynamic properties.
[0561] It is clear from Examples 34 and 35 that the poly (phenylene
ether ether ketone) oligomer (B) in the present invention can be
satisfactorily polymerized even at 350.degree. C. and 300.degree.
C., and these methods are excellent in process temperature in the
production of a molding material.
[0562] It is clear from Example 36 that even when the content of
the reinforcing fiber substrate (A') is 76 wt %, the method for
producing a molding material of the present invention is excellent
in the process temperature and impregnation properties in the
production of a molding material, and the molded article obtained
by using this molding material has excellent dynamic
properties.
Method for Producing Fiber-Reinforced Composite Material by RTM
Method
Example 37
[0563] Step (I-1):
[0564] Eight plies of "TORAYCA" (registered trademark) BT70-30
(carbon fiber fabric available from TORAY INDUSTRIES, INC.,
T700S-12K, texture: plain, basis weight: 300 g/m.sup.2) used as a
reinforcing fiber substrates (A') were laminated in a mold having a
plate-like cavity 300 mm long.times.300 mm wide.times.2 mm thick,
and clamped with a pressing device.
[0565] Step (II-1):
[0566] The poly (phenylene ether ether ketone) oligomer (B)
obtained in Reference Example 1 was melted by heating at
230.degree. C. for 30 minutes to form a melt solution. A given
amount of polymerization catalyst (D) was further added to the melt
solution and kneaded for dispersion.
[0567] Step (III-1):
[0568] The surface temperature of the mold was maintained at
300.degree. C., and the pressure in the mold was reduced with a
vacuum pump to a pressure 0.1 MPa lower than the atmospheric
pressure. The melt solution was injected into the mold using a
resin injector to impregnate the poly (phenylene ether ether
ketone) oligomer (B) into the reinforcing fiber substrate (A').
[0569] Step (IV-1):
[0570] After completion of the injection of the melt solution,
while still maintaining the surface temperature of the mold at
300.degree. C., heating was continued for 30 minutes to polymerize
the poly (phenylene ether ether ketone) oligomer (B) into a poly
(phenylene ether ether ketone) (B').
[0571] After completion of the steps (I-1) to (IV-1), the mold was
opened and demolded to obtain a fiber-reinforced composite
material.
[0572] Resin flash was removed to measure the weight of the
fiber-reinforced composite material obtained. The content of the
reinforcing fiber substrate (A') was calculated from the weight of
the fiber-reinforced composite material and the weight of the
reinforcing fiber substrate (A') used.
[0573] The poly (phenylene ether ether ketone) (B') was physically
separated from the fiber-reinforced composite material obtained and
subjected to melting point measurement, melting enthalpy
measurement, and viscosity measurement.
[0574] From the fiber-reinforced composite material obtained, a
test piece having a size in accordance with JIS K 7074-1988 was cut
out with the warp direction of the reinforcing fiber substrate (A')
used as the long side. A 3-point flexural test was performed using
"INSTRON" (registered trademark) universal tester Model 4201
(manufactured by INSTRON) as a tester to determine the flexural
strength. The process conditions and the evaluation results are
shown in Table 7.
Example 38
[0575] A fiber-reinforced composite material was produced in the
same manner as in Example 37 except that the poly (phenylene ether
ether ketone) oligomer (B) prepared in Reference Example 2 was
used. The fiber-reinforced composite material obtained was
evaluated in the same manner as in Example 37. The process
conditions and the evaluation results are shown in Table 7.
Comparative Example 18
[0576] A fiber-reinforced composite material was produced in the
same manner as in Example 37 except that the poly (phenylene ether
ether ketone) oligomer (B) prepared in Reference Example 3 was
used; the heat-melting temperature in the step (II-1) was changed
to 350.degree. C.; the surface temperature of the mold in the steps
(III-1) and (IV-1) was changed to 400.degree. C.; the heating time
in the step (IV-1) was changed to 10 minutes; and, further, the
surface temperature of the mold was decreased from 400.degree. C.
to 150.degree. C. over 25 minutes before demolding a
fiber-reinforced composite material. The fiber-reinforced composite
material obtained was evaluated in the same manner as in Example
37. The fiber-reinforced composite material obtained here had many
voids compared to Example 37, and the fiber-reinforced composite
material obtained was very fragile. This is probably because the
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) occurred before impregnation into a reinforcing fiber substrate
(A'). The process conditions and the evaluation results are shown
in Table 7.
Example 39
[0577] A fiber-reinforced composite material was produced in the
same manner as in Example 37 except that the poly (phenylene ether
ether ketone) oligomer (B) prepared in Reference Example 4 was
used. The fiber-reinforced composite material obtained was
evaluated in the same manner as in Example 37. The process
conditions and the evaluation results are shown in Table 7.
Comparative Example 19
[0578] A fiber-reinforced composite material was produced in the
same manner as in Example 37 except that VICTREX "PEEK" (registered
trademark) 151G (polyether ether ketone resin available from
Victrex-MC, Inc., melting point: 343.degree. C., melt viscosity at
400.degree. C.: 150 Pas) was used in place of the poly (phenylene
ether ether ketone) oligomer (B); the heat-melting temperature in
the step (II-1) was changed to 400.degree. C.; the surface
temperature of the mold in the steps (III-1) and (IV-1) was changed
to 400.degree. C.; the heating time in the step (IV-1) was changed
to 10 minutes; and, further, the surface temperature of the mold
was decreased from 400.degree. C. to 150.degree. C. over 25 minutes
before demolding a fiber-reinforced composite material. The
fiber-reinforced composite material obtained was evaluated in the
same manner as in Example 37. The fiber-reinforced composite
material obtained here had many voids compared to Example 37, and
the fiber-reinforced composite material obtained was very fragile.
This is probably because the polymerization of the poly (phenylene
ether ether ketone) oligomer (B) occurred before impregnation into
a reinforcing fiber substrate (A'). The process conditions and the
evaluation results are shown in Table 7.
Example 40
[0579] A fiber-reinforced composite material was produced in the
same manner as in Example 7 except that the surface temperature of
the mold in the steps (III-1) and (IV-1) was changed to 350.degree.
C.; the heating time in the step (IV-1) was changed to 10 minutes;
and, further, the surface temperature of the mold was decreased
from 350.degree. C. to 150.degree. C. over 20 minutes before
demolding a fiber-reinforced composite material. The
fiber-reinforced composite material obtained was evaluated in the
same manner as in Example 37. The process conditions and the
evaluation results are shown in Table 7.
Example 41
[0580] A fiber-reinforced composite material was produced in the
same manner as in Example 37 except that the surface temperature of
the mold in the steps (III-1) and (IV-1) was changed to 400.degree.
C.; the heating time in the step (IV-1) was changed to 10 minutes;
and, further, the surface temperature of the mold was decreased
from 400.degree. C. to 150.degree. C. over 25 minutes before
demolding a fiber-reinforced composite material. The
fiber-reinforced composite material obtained was evaluated in the
same manner as in Example 37. The process conditions and the
evaluation results are shown in Table 7.
TABLE-US-00007 TABLE 7 Comparative Comparative Example 37 Example
38 Example 18 Example 39 Example 19 Example 40 Example 41
(Composition) Component (B): Poly Type Reference Reference
Reference Reference High molecular Reference Reference (phenylene
ether Example 1 Example 2 Example 3 Example 4 weight PEEK Example 1
Example 1 ether ketone) oligomer wt % 100 100 100 100 100 100 100
Component (D): Type CsF CsF CsF CsF -- CsF CsF Polymerization
catalyst mol % 5 5 5 5 5 5 (Producing conditions of
Fiber-reinforced composite material) <Step (II-1)> Heat
melting temperature .degree. C. 230 230 350 230 400 230 230 Melt
viscosity of Pa s 0.034 0.030 0.15 0.036 150 0.034 0.034 Component
(B) <Step (III-1)> Mold surface temperature .degree. C. 300
300 400 300 400 350 400 <Step (IV-1)> Mold surface
temperature .degree. C. 300 300 400 300 400 350 400 Heating time
min 30 30 10 30 10 10 1.0 Mold cooling time min -- -- 25 -- 25 20
25 (Properties of Poly (phenylene ether ether ketone) (B')) Melting
point .degree. C. 347 346 335 344 343 330 329 Fusion enthalpy J/g
53 52 32 53 -- 36 38 Reduced viscosity dL/g 0.5 0.5 0.6 0.5 -- 0.6
0.7 (Properties of Fiber- reinforced composite material Flexural
strength MPa 850 800 -- 800 -- 800 850 Component (A') wt % 58 58 --
58 -- 58 58 content Void ratio of Fiber- -- good good fair good bad
good good reinforced composite material
[0581] Examples and Comparative Examples in Table 7 reveal the
following. It is clear from the results of Examples 37 to 39 that
regardless of the production method, the poly (phenylene ether
ether ketone) oligomer (B) in the present invention, as compared to
Comparative Examples 18 and 19, can decrease the process
temperature in the production of a fiber-reinforced composite
material, is excellent in impregnation into the reinforcing fiber
substrate (A'), and can reduce voids in the resulting
fiber-reinforced composite material. Further, it is clear that the
resulting fiber-reinforced composite material has excellent dynamic
properties.
[0582] It is clear from Examples 40 and 41 that the poly (phenylene
ether ether ketone) oligomer (B) in the present invention can be
satisfactorily polymerized even at 350.degree. C. and 400.degree.
C., and these methods are excellent in polymerization rate.
Method for Producing Fiber-Reinforced Composite Material by
Filament Winding Method
Example 42
[0583] Description will be given with reference to FIGS. 16 and
17.
[0584] Step (I-2):
[0585] "TORAYCA" (registered trademark) T700S-24K (carbon fiber
available from TORAY INDUSTRIES, INC.) used as a reinforcing fiber
substrate (A') was continuously drawn, and three of them were
aligned.
[0586] Step (II-2):
[0587] The poly (phenylene ether ether ketone) oligomer (B)
obtained in Reference Example 1 and a polymerization catalyst (D)
were fed to an impregnation bath and melted by heating at
230.degree. C. to form a melt solution.
[0588] Step (III-2):
[0589] The reinforcing fiber substrate (A') aligned in the step
(I-2) was fed to the impregnation bath of the step (II-2) to obtain
a composite of the melt solution and the reinforcing fiber
substrate (A') impregnated therewith. Using the filament winding
method, the composite obtained was spirally wound around a mandrel
(.phi.: 70 mm) to form as an inner layer a 0.2-mm spirally wound
layer 72a at 85.degree. to the axial direction; next, the composite
was spirally wound as a main layer 72b at .+-.12.degree. with a
thickness of 1 mm, at .+-.45.degree. with a thickness of 0.5 mm,
and at .+-.12.degree. with a thickness of 1 mm; and then a spirally
wound layer 72c at 85.degree. with a thickness of 0.2 mm was formed
as an outermost layer. The main layer has a thickness of 2.9 mm in
total. At a part corresponding to a 110-mm-long region at both ends
of a cylindrical body, which part is a part for mounting a joint, a
reinforcing layer 72d at .+-.83.degree. to the axial direction with
a thickness of 2.5 mm was formed in order to enhance the connection
strength to the joint. The reinforcing layer 72d is composed of a
straight part 2.5 mm thick and 60 mm long in the axial direction
and a 50-mm-long tapering part tapering toward the axial
center.
[0590] Step (IV-2):
[0591] The mandrel around which the composite was wound in the step
(III-2) is heated in an oven at 300.degree. C. for 30 minutes to
polymerize the poly (phenylene ether ether ketone) oligomer
(B).
[0592] Further, the mandrel after the step (IV-2) was taken out of
the oven and air-cooled to obtain a cylindrical body 72 made of a
fiber-reinforced composite material. Further, metal joints 73 were
press-fit connected to both ends of the cylindrical body 72 to form
a propeller shaft 71.
[0593] The content of the reinforcing fiber substrate (A') was
calculated from the weight of the obtained cylindrical body 72 made
of a fiber-reinforced composite material excluding the mandrel and
the weight of the reinforcing fiber substrate (A') used.
[0594] The poly (phenylene ether ether ketone) (B') was physically
separated from the fiber-reinforced composite material obtained and
subjected to melting point measurement, melting enthalpy
measurement, and viscosity measurement. The process conditions and
the evaluation results are shown in Table 8.
Example 43
[0595] A fiber-reinforced composite material was produced in the
same manner as in Example 42 except that the conditions of heating
in an oven in the step (IV-2) were changed to 400.degree. C. for 10
minutes. The fiber-reinforced composite material obtained was
evaluated in the same manner as in Example 42. The process
conditions and the evaluation results are shown in Table 8.
Comparative Example 20
[0596] A fiber-reinforced composite material was produced in the
same manner as in Example 42 except that the poly (phenylene ether
ether ketone) oligomer (B) prepared in Reference Example 3 was
used; the heat-melting temperature in the step (II-2) was changed
to 350.degree. C.; and the conditions of heating in an oven in the
step (IV-2) were changed to 400.degree. C. for 10 minutes. The
fiber-reinforced composite material obtained was evaluated in the
same manner as in Example 42. The fiber-reinforced composite
material obtained here had many voids compared to Example 42. This
is probably because the polymerization of the poly (phenylene ether
ether ketone) oligomer (B) occurred before impregnation into a
reinforcing fiber substrate (A'). The process conditions and the
evaluation results are shown in Table 8.
Comparative Example 21
[0597] A fiber-reinforced composite material was produced in the
same manner as in Example 42 except that VICTREX "PEEK" (registered
trademark) 151G (polyether ether ketone resin available from
Victrex-MC, Inc., melting point: 343.degree. C., melt viscosity at
400.degree. C.: 150 Pas) was used in place of the poly (phenylene
ether ether ketone) oligomer (B); the heat-melting temperature in
the step (II-2) was changed to 400.degree. C.; and the conditions
of heating in an oven in the step (IV-2) were changed to
400.degree. C. for 10 minutes. The fiber-reinforced composite
material obtained was evaluated in the same manner as in Example
42. The fiber-reinforced composite material obtained here had many
voids compared to Example 42. This is probably because the
polymerization of the poly (phenylene ether ether ketone) oligomer
(B) occurred before impregnation into a reinforcing fiber substrate
(A'). The process conditions and the evaluation results are shown
in Table 8.
TABLE-US-00008 TABLE 8 Comparative Comparative Example 42 Example
43 Example 20 Example 21 (Composition) Component (B): Poly
(phenylene Type Reference Reference Reference High molecular ether
ether ketone) oligomer Example 1 Example 1 Example 3 weight PEEK wt
% 100 100 100 100 Component (D): Polymerization Type CsF CsF CsF --
catalyst mol % 5 5 5 (Producing conditions of Fiber- reinforced
composite material) <Step (II-2)> Heat melting temperature
.degree. C. 230 230 350 400 Melt viscosity of Component (B) Pa s
0.034 0.034 0.15 150 <Step (IV-2)> Oven temperature .degree.
C. 300 400 400 400 Heating time min 30 10 10 10 (Properties of Poly
(phenylene ether ether ketone) (B')) Melting point .degree. C. 346
331 333 343 Fusion enthalpy J/g 51 37 31 -- Reduced viscosity dL/g
0.5 0.7 0.6 -- (Properties of Fiber-reinforced composite material)
Component (A') content wt % 73 74 -- -- Void ratio of
Fiber-reinforced -- good good fair bad composite material
[0598] Examples and Comparative Examples in Table 8 reveal the
following. It is clear from the comparison between Example 42 and
Comparative Examples 20 and 21 that by using the poly (phenylene
ether ether ketone) oligomer (B) in the present invention, the
process temperature in the production of a fiber-reinforced
composite material can be decreased; the impregnation into the
reinforcing fiber substrate (A') is excellent; and voids in the
resulting fiber-reinforced composite material can be reduced.
[0599] It is clear from Example 43 that the poly (phenylene ether
ether ketone) oligomer (B) in the present invention can be
satisfactorily polymerized even at 400.degree. C., and this method
is excellent in polymerization rate.
Method for Producing Fiber-Reinforced Composite Material by
Pultrusion Molding Method
Example 44
[0600] Step (I-3):
[0601] One hundred and twelve pieces of "TORAYCA" (registered
trademark) T700S-24K (carbon fiber available from TORAY INDUSTRIES,
INC.) used as a reinforcing fiber substrate (A') were continuously
drawn.
[0602] Step (II-3):
[0603] The poly (phenylene ether ether ketone) oligomer (B)
obtained in Reference Example 1 and a polymerization catalyst (D)
were fed to an impregnation bath and melted by heating at
230.degree. C. to form a melt solution.
[0604] Step (III-3):
[0605] The reinforcing fiber substrate (A') drawn in the step (I-3)
was fed to the impregnation bath of the step (II-3) to impregnate
the melt solution into the reinforcing fiber substrate (A') and
further passed through a squeeze die to obtain a composite from
which excess melt solution was removed.
[0606] Step (IV-3):
[0607] The composite obtained in the step (III-3) was fed to a mold
having such an opening that provides a fiber-reinforced composite
material 100 mm wide and 1.4 mm thick, and heated in the mold at
300.degree. C. for 30 minutes to polymerize the poly (phenylene
ether ether ketone) oligomer (B).
[0608] The composite after the step (IV-3) was solidified in
contact with a cooling roll at 150.degree. C. and further drawn
with a belt conveyor to continuously obtain a fiber-reinforced
composite material.
[0609] The content of the reinforcing fiber substrate (A') was
calculated from the weight of the fiber-reinforced composite
material obtained and the weight of the reinforcing fiber substrate
(A') used.
[0610] The poly (phenylene ether ether ketone) (B') was physically
separated from the fiber-reinforced composite material obtained and
subjected to melting point measurement, melting enthalpy
measurement, and viscosity measurement. The process conditions and
the evaluation results are shown in Table 9.
Example 45
[0611] A fiber-reinforced composite material was produced in the
same manner as in Example 44 except that the conditions of heating
in a mold in the step (IV-3) were changed to 400.degree. C. for 10
minutes. The fiber-reinforced composite material obtained was
evaluated in the same manner as in Example 44. The process
conditions and the evaluation results are shown in Table 9.
Comparative Example 22
[0612] A fiber-reinforced composite material was produced in the
same manner as in Example 44 except that the poly (phenylene ether
ether ketone) oligomer (B) prepared in Reference Example 3 was
used; the heat-melting temperature in the step (II-3) was changed
to 350.degree. C.; and the conditions of heating in a mold in the
step (IV-3) were changed to 400.degree. C. for 10 minutes. The
fiber-reinforced composite material obtained was evaluated in the
same manner as in Example 44. The fiber-reinforced composite
material obtained here had many voids compared to Example 44. This
is probably because the polymerization of the poly (phenylene ether
ether ketone) oligomer (B) occurred before impregnation into a
reinforcing fiber substrate (A'). The process conditions and the
evaluation results are shown in Table 9.
Comparative Example 23
[0613] A fiber-reinforced composite material was produced in the
same manner as in Example 44 except that VICTREX "PEEK" (registered
trademark) 151G (polyether ether ketone resin available from
Victrex-MC, Inc., melting point: 343.degree. C., melt viscosity at
400.degree. C.: 150 Pa's) was used in place of the poly (phenylene
ether ether ketone) oligomer (B); the heat-melting temperature in
the step (II-3) was changed to 400.degree. C.; and the conditions
of heating in a mold in the step (IV-3) were changed to 400.degree.
C. for 10 minutes. The fiber-reinforced composite material obtained
was evaluated in the same manner as in Example 44. The
fiber-reinforced composite material obtained here had many voids
compared to Example 44. This is probably because the polymerization
of the poly (phenylene ether ether ketone) oligomer (B) occurred
before impregnation into a reinforcing fiber substrate (A'). The
process conditions and the evaluation results are shown in Table
9.
TABLE-US-00009 TABLE 9 Comparative Comparative Example 44 Example
45 Example 22 Example 23 (Composition) Component (B): Poly
(phenylene Type Reference Reference Reference High molecular ether
ether ketone) oligomer Example 1 Example 1 Example 3 weight PEEK wt
% 100 100 100 100 Component (D): Polymerization Type CsF CsF CsF --
catalyst mol % 5 5 5 (Producing conditions of Fiber- reinforced
composite material) <Step (II-3)> Heat melting temperature
.degree. C. 230 230 350 400 Melt viscosity of Component (B) Pa s
0.034 0.034 0.15 150 <Step (IV-3)> Mold surface temperature
.degree. C. 300 400 400 400 Heating time min 30 10 10 10
(Properties of Poly (phenylene ether ether ketone) (B')) Melting
point .degree. C. 345 329 332 343 Fusion enthalpy J/g 52 38 35 --
Reduced viscosity dL/g 0.5 0.7 0.6 -- (Properties of
Fiber-reinforced composite material) Component (A') content wt % 76
76 -- -- Void ratio of Fiber-reinforced -- good good fair bad
composite material
[0614] Examples and Comparative Examples in Table 9 reveal the
following. It is clear from the comparison between Example 44 and
Comparative Examples 22 and 23 that by using the poly (phenylene
ether ether ketone) oligomer (B) in the present invention, the
process temperature in the production of a fiber-reinforced
composite material can be decreased; the impregnation into the
reinforcing fiber substrate (A') is excellent; and voids in the
resulting fiber-reinforced composite material can be reduced.
[0615] It is clear from Example 45 that the poly (phenylene ether
ether ketone) oligomer (B) in the present invention can be
satisfactorily polymerized even at 400.degree. C., and this method
is excellent in polymerization rate.
[0616] The molding material of the present invention in the first
preferred embodiment comprises a poly (phenylene ether ether
ketone) oligomer (B), and thus by using the molding material
excellent in economic efficiency and productivity, a molded article
having excellent dynamic properties can be easily produced.
[0617] The molding material of the present invention in the second
preferred embodiment comprises a poly (phenylene ether ether
ketone) (B'), and thus a molded article having excellent dynamic
properties and heat resistance can be easily produced.
[0618] The molding material of the present invention in the third
preferred embodiment can be molded into a fiber-reinforced
composite material by heating the molding material at a low
temperature for a short time, and thus it is excellent in economic
efficiency, productivity, and handleability.
[0619] The method for producing a molding material of the present
invention enables easy combination of a reinforcing fiber substrate
with a poly (phenylene ether ether ketone) and, therefore, can
increase economic efficiency and productivity. Thus the method is
useful for producing a molding material.
[0620] The method for producing a fiber-reinforced composite
material of the present invention enables easy combination of a
reinforcing fiber substrate with a poly (phenylene ether ether
ketone) and, therefore, can increase economic efficiency and
productivity. Thus the method is useful for producing a
fiber-reinforced composite material.
DESCRIPTION OF SYMBOLS
[0621] 1: Reinforcing fiber bundle (A) [0622] 2: Poly (phenylene
ether ether ketone) oligomer (B), or poly (phenylene ether ether
ketone) oligomer (B) or poly (phenylene ether ether ketone) (B')
and polymerization catalyst (D) [0623] 3: Composite of reinforcing
fiber bundle (A) and poly (phenylene ether ether ketone) oligomer
(B), or of reinforcing fiber bundle (A), poly (phenylene ether
ether ketone) oligomer (B) or poly (phenylene ether ether ketone)
(B'), and polymerization catalyst (D) [0624] 4: Thermoplastic resin
(C) [0625] 5: Fixture for evaluating drape property [0626] 6:
Sample for evaluating drape property [0627] 7: Heavy bob [0628] 8:
Clamp for fixing sample [0629] 11, 31, 51: Roll bar [0630] 12:
Impregnation bath [0631] 13: Rotating roller [0632] 14: Hot-air
drying furnace [0633] 15: Double belt press [0634] 16, 34, 53: Nip
roller [0635] 17, 36, 55, 62: Infrared heater [0636] 18: Pump
[0637] 19: Chamber [0638] 20, 26, 41, 58: Inlet port [0639] 21, 42,
59: Cooling plate [0640] 22: Guillotine cutter [0641] 23, 43, 60:
Reinforcing fiber bundle [0642] 24, 44, 61: Molding material [0643]
32: Belt conveyor [0644] 35, 54: Drum winder [0645] 37: Draw winder
[0646] 27, 33, 38: Hot roller [0647] 39: Take-up winder [0648] 25,
40, 57: Heating chamber [0649] 52: Calender roll [0650] 56:
Metering powder feeder [0651] 71: Propeller shaft [0652] 72:
Cylindrical body made of fiber-reinforced composite material [0653]
72a: Inner layer [0654] 72b: Main layer [0655] 72c: Outer layer
[0656] 72d: Reinforcing layer [0657] 73: Metal joint
* * * * *