U.S. patent application number 09/402094 was filed with the patent office on 2002-01-17 for flame-retardant thermoplastic resin composition and products of injection molding thereof.
Invention is credited to KOBAYASHI, KAZUHITO, MURAKAMI, HARUJI, OHTAKE, MINEO.
Application Number | 20020006995 09/402094 |
Document ID | / |
Family ID | 13820637 |
Filed Date | 2002-01-17 |
United States Patent
Application |
20020006995 |
Kind Code |
A1 |
MURAKAMI, HARUJI ; et
al. |
January 17, 2002 |
FLAME-RETARDANT THERMOPLASTIC RESIN COMPOSITION AND PRODUCTS OF
INJECTION MOLDING THEREOF
Abstract
A flame-retardant thermoplastic resin composition, which
comprises a polymer alloy composed of a thermoplastic resin (A) and
a liquid-crystal polymer (B), is excellent in the stability of the
heat retentivity imparted thereto in the injection molding step,
exhibits an extremely high reinforcing effect which has been
unattainable heretofore because the liquid-crystal polymer can be
readily fiberized in the molding step, and provides moldings
excellent in flame retardancy. Injection moldings comprising a
liquid-crystal polymer (B) in the form of fibers having an average
aspect ratio of at least 6 and micro-dispersed in a matrix phase
comprising a thermoplastic resin (A), are produced by
injection-molding a flame-retardant thermoplastic resin composition
obtained by blending 100 parts by weight of the resin component
comprising: (A) 99 to 50 parts by weight of a thermoplastic resin
not forming an anisotropic molten phase and (B) 1 to 50 parts by
weight of a liquid-crystal polymer capable of forming an
anisotropic molten phase with: (C) 1.0 to 20 parts by weight of a
halogen-containing organic compound and (D) 0.01 to 10 parts by
weight of a fluorine compound.
Inventors: |
MURAKAMI, HARUJI; (SHIZUOKA,
JP) ; OHTAKE, MINEO; (SHIZUOKA, JP) ;
KOBAYASHI, KAZUHITO; (SHIZUOKA, JP) |
Correspondence
Address: |
BURNS DOANE SWECKER & MATHIS L L P
POST OFFICE BOX 1404
ALEXANDRIA
VA
22313-1404
US
|
Family ID: |
13820637 |
Appl. No.: |
09/402094 |
Filed: |
September 29, 1999 |
PCT Filed: |
April 1, 1998 |
PCT NO: |
PCT/JP98/01506 |
Current U.S.
Class: |
524/412 ;
524/265; 525/437 |
Current CPC
Class: |
C08L 2666/02 20130101;
C08L 2666/02 20130101; C08L 67/00 20130101; C08L 69/00 20130101;
C08L 69/00 20130101; C08L 67/00 20130101; C08L 27/18 20130101; C08L
67/02 20130101; C08L 67/02 20130101; C08L 69/00 20130101 |
Class at
Publication: |
524/412 ;
524/265; 525/437 |
International
Class: |
C08K 003/10; C08K
005/24; C08F 020/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 2, 1997 |
JP |
9/84084 |
Claims
1. A flame-retardant thermoplastic resin composition obtained by
blending 100 parts by weight of the resin component comprising: (A)
99 to 50 parts by weight of a thermoplastic resin which forms no
anisotropic molten phase and (B) 1 to 50 parts by weight of a
liquid-crystal polymer capable of forming an anisotropic molten
phase with: (C) 1.0 to 20 parts by weight of a halogen-containing
organic compound, and (D) 0.01 to 10 parts by weight of a fluorine
compound.
2. The flame-retardant thermoplastic resin composition according to
claim 1, wherein the halogen-containing organic compound (C) is a
brominated polycarbonate and the fluorine compound (D) is a
fluororesin.
3. The flame-retardant thermoplastic resin composition according to
claim 1 or 2, wherein the fluorine compound (D) is a fluororesin
which is fiberized by a shearing force.
4. The flame-retardant thermoplastic resin composition according to
any of claims 1 to 3, wherein the thermoplastic resin (A) is a
polyester resin.
5. The flame-retardant thermoplastic resin composition according to
claim 4, wherein the thermoplastic resin (A) is a polycarbonate
resin.
6. The flame-retardant thermoplastic resin composition according to
any of claims 1 to 5, wherein 100 parts by weight of the resin
component comprising 99 to 50 parts by weight of the thermoplastic
resin (A) and 1 to 50 parts by weight of the liquid-crystal polymer
(B) are further blended with at least one compound (E) selected
from among phosphoric acid, phosphorous acid, and metal salts
thereof in an amount of at least 0.01 to less than 1.0 part by
weight.
7. The flame-retardant thermoplastic resin composition according to
any of claims 1 to 5, wherein 100 parts by weight of the resin
component comprising 99 to 50 parts by weight of the thermoplastic
resin (A) and 1 to 50 parts by weight of the liquid-crystal polymer
(B) are further blended with at least one inorganic compound (F)
selected from among phosphoric and phosphorous esters in an amount
of 0.01 to 3.0 parts by weight.
8. The flame-retardant thermoplastic resin composition according to
any of claims 1 to 7, wherein 100 parts by weight of the resin
component comprising 99 to 50 parts by weight of the thermoplastic
resin (A) and 1 to 50 parts by weight of the liquid-crystal polymer
(B) are further blended with at least one silane compound (G)
selected from among vinylalkoxysilanes, aminoalkoxysilanes and
mercaptoalkoxysilanes in an amount of 0.01 to 3.0 parts by
weight.
9. Injection moldings produced by injection-molding the
flame-retardant thermoplastic resin composition according to any of
claims 1 to 8, characterized in that the liquid-crystal polymer (B)
is micro-dispersed in the form of fibers having an average aspect
ratio of at least 6 in the matrix phase comprising the
thermoplastic resin (A).
Description
BACKGROUND OF INVENTION
[0001] 1. Technical Field to which the Invention Belongs
[0002] The present invention relates to a flame-retardant
thermoplastic resin composition obtained by blending (A) a
thermoplastic resin which forms no anisotropic molten phase and (B)
a liquid-crystal polymer capable of forming an anisotropic molten
phase with (C) a halogen-containing organic compound and (D) a
fluorine compound, and injection moldings thereof.
[0003] 2. Prior Art
[0004] An alloy of a thermoplastic resin and a liquid-crystal
polymer has been so far known for a material having excellent
characteristics as a thin molding material, as described in JP-A
7-179743. This alloy is a material having both an inexpensiveness
of the thermoplastic resin and mechanical properties and an easy
moldability of the liquid-crystal polymer. Further, the greatest
characteristics of this alloy are that the liquid-crystal polymer
is readily fiberized through injection-molding to exhibit a much
higher reinforcing effect than ever, and that the properties of the
resulting moldings are therefore so specific that thin moldings
excellent particularly in the mechanical strength can be provided.
However, in the recent electric and electronic fields, the flame
retardancy has been often required from necessity. In order to have
a resin flame-retardant, it is considered that a combination of a
usual flame retardant and a usual flame retardant aid is blended
with it, like with a general thermoplastic resin. Nevertheless, in
case of this alloy, there have been problems that, when an antimony
compound or the like often used as a flame retardant aid is
employed, a catalytic activity acts in imparting a heat retentivity
and a reaction arises between a thermoplastic resin and a
liquid-crystal polymer, so that fibers of the liquid-crystal
polymer to be inherently formed in a matrix phase of the
thermoplastic resin in the injection-molding can not be formed, for
which a thin moldability and a high rigidity, as one of the
characteristics of this composition, are impaired.
DISCLOSURE OF THE INVENTION
SUMMARY OF THE INVENTION
[0005] The present inventors have assiduously conducted
investigations in view of the above-mentioned problems, and have
consequently found that a thermoplastic resin composition, having
an excellent stability of a heat retentivity imparted when
injection-molding it, exhibiting an extremely high reinforcing
effect which has been heretofore unattainable because the
liquid-crystal polymer can be readily fiberized in moldings by
injection-molding this, and also having an excellent flame
retardancy, can be obtained by blending a resin component composed
of (A) a thermoplastic resin and (B) a liquid-crystal polymer with
(C) a halogen-containing organic compound and (D) a fluorine
compound. This finding has led to completion of the present
invention.
[0006] That is, an object of the present invention is a
flame-retardant thermoplastic resin composition wherein 100 parts
by weight of a resin component composed of 99 to 50 parts by weight
of a thermoplastic resin (A) not forming an anisotropic molten
phase and 1 to 50 parts by weight of a liquid-crystal polymer (B)
capable of forming an anisotropic molten phase are blended with 1.0
to 20 parts by weight of a halogen-containing organic compound (C)
and 0.01 to 10 parts by weight of a fluorine compound (D). Another
object of the present invention is injection moldings obtained by
injection-molding said flame-retardant thermoplastic resin
composition, wherein the liquid-crystal polymer (B) is
micro-dispersed in the form of fibers having an average aspect
ratio of at least 6 in a matrix phase of the thermoplastic resin
(A).
DETAILED DESCRIPTION OF THE INVENTION
[0007] Hereinafter, the constitution of the present invention will
be described in detail.
[0008] The thermoplastic resin (A) not forming an anisotropic
molten phase used in the present invention may be any thermoplastic
resin usually used, and examples thereof include polyolefin
(co)polymer such as polyethylene, polypropylene and
poly(4-methylpentene-1), polyester resin such as polyethylene
terephthalate resin, polybutylene terephthalate resin and
polycarbonate resin, polyamide polymer, syndiotactic polystyrene
(SPS) resin, ABS resin, polyarylene sulfide resin, polyacrylarylate
resin, polyacetal resin, polyphenylene oxide resin and a resin
mainly comprising them. One or more of these resins may be
used.
[0009] Among them, polyester resin such as polycarbonate resin and
polybutylene terephthalate resin, SPS resin and polyarylene sulfide
resin are preferable in respect of the thermal resistance, and the
polycarbonate resin is especially preferable because it has
relatively low molding shrinkage and linear expansion coefficient.
Moreover, the polyester resin, especially the polycarbonate resin
has the remarkable effect of the present invention in that, when an
antimony compound or the like is used as usual, a catalytic
activity acts in imparting a heat retentivity and a reaction to the
liquid-crystal polymer tends to occur.
[0010] The thermoplastic resin of the present invention includes
one provided with desired properties by adding additives to the
thermoplastic resin, for example, nucleating agent, pigment such as
carbon black, antioxidant, stabilizer, plasticizer, lubricant, mold
releasing agent and flame retardant.
[0011] The liquid-crystal polymer (B) used in the present invention
refers to a melt-processed polymer with the property that it can
form an optically anisotropic molten phase.
[0012] The properties of an anisotropic molten phase can be
confirmed by the conventional polarization inspection method using
orthogonal polarizers. More specifically, confirmation of
anisotropy in a molten phase can be attained by using a Leitz
polarization microscope and observing a molten sample mounted on a
Leitz hot stage under the nitrogen atmosphere at a magnification of
40 times. The liquid-crystal polymer usable in the present
invention exhibits an optical anisotropy wherein a polarized light
penetrates even in a static molten phase, when observed between
cross polarizers.
[0013] As the liquid-crystal polymer usable in the present
invention, aromatic polyester and aromatic polyester amide are an
aromatic polyester or a liquid-crystal aromatic polyester amide
containing at least one compound selected from the group consisting
of aromatic hydroxycarboxylic acid, aromatic hydroxyamine and
aromatic diamine.
[0014] More specifically, the followings are cited:
[0015] 1) polyester or polyester amide mainly comprising one or two
or more of aromatic hydroxycarboxylic acid, aromatic
aminocarboxylic acid and derivatives thereof;
[0016] 2) polyester or polyester amide mainly comprising
[0017] a) one or two or more of aromatic hydroxycarboxylic acid,
aromatic aminocarboxylic acid and derivatives thereof,
[0018] b) one or two or more of aromatic dicarboxylic acid,
alicyclic dicarboxylic acid, aliphatic dicarboxylic acid and
derivatives thereof, and
[0019] c) one or two or more of aromatic diol, alicyclic diol,
aliphatic diol and derivatives thereof;
[0020] 3) polyester amide mainly comprising
[0021] a) one or two or more of aromatic hydroxycarboxylic acid,
aromatic aminocarboxylic acid and derivatives thereof,
[0022] b) one or two or more of aromatic hydroxyamine, aromatic
diamine and derivatives thereof, and
[0023] c) one or two or more of aromatic dicarboxylic acid,
alicyclic dicarboxylic acid, aliphatic dicarboxylic acid and
derivatives thereof;
[0024] 4) polyester amide mainly comprising
[0025] a) one or two or more of aromatic hydroxycarboxylic acid,
aromatic aminocarboxylic acid and derivatives thereof,
[0026] b) one or two or more of aromatic hydroxyamine, aromatic
diamine and derivatives thereof,
[0027] c) one or two or more of aromatic dicarboxylic acid,
alicyclic dicarboxylic acid, aliphatic dicarboxylic acid and
derivatives thereof, and
[0028] d) one or two or more of aromatic diol, alicyclic diol,
aliphatic diol and derivatives thereof;
[0029] 5) polyester or polyester amide mainly comprising
[0030] a) one or two or more of aromatic hydroxycarboxylic acid,
aromatic aminocarboxylic acid and derivatives thereof, and
[0031] b) one or two or more of aromatic dicarboxylic acid,
alicyclic dicarboxylic acid, aliphatic dicarboxylic acid and
derivatives thereof; and
[0032] 6) polyester or polyester amide mainly comprising
[0033] a) one or two or more of aromatic hydroxycarboxylic acid,
aromatic aminocarboxylic acid and derivatives thereof, and
[0034] b) one or two or more of aromatic diol, alicyclic diol,
aliphatic diol and derivatives thereof.
[0035] Furthermore, a molecular weight modifier may be used
together with the above-mentioned components if necessary. Examples
of the molecular weight modifier include a monofunctional component
such as benzoic acid, phenol and p-phenylphenol.
[0036] Preferred examples of the concrete compounds constituting
the above-described liquid-crystal polymer usable in the present
invention include: aromatic hydroxycarboxylic acid such as
p-hydroxybenzoic acid, m-hydroxybenzoic acid, 6-hydroxy-2-naphthoic
acid and 5-hydroxy-1-naphthoic acid; aromatic aminocarboxylic acid
such as p-amino benzoic acid and m-amino benzoic acid; aromatic
diol such as 2,6-dihydroxy naphthalene, 1,4-dihydroxy naphthalene,
1,5-dihydroxy naphthalene, 2,7-dihydroxy naphthalene,
4,4'-dihydroxy biphenyl, hydroquinone, resorcin and compounds
represented by the following general formulas (I) or (II);
aliphatic glycol represented by ethylene glycol and 1,4-butanediol;
aromatic dicarboxylic acid such as terephthalic acid, isophthalic
acid, 4,4'-biphenyl dicarboxylic acid, 3,4'-biphenyl dicarboxylic
acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene
dicarboxylic acid, 1,4-naphthalene dicarboxylic acid,
1,5-naphthalene dicarboxylic acid and compounds represented by the
following general formula (III); and aromatic diamine such as
p-aminophenol, m-aminophenol, 1,4-phenylene diamine and
1,4-phenylene diamine; 1
[0037] wherein X denotes a group selected from alkylene (C.sub.1 to
C.sub.4), alkylydene, --O--, --SO--, --SO.sub.2--, --S--, --CO--,
and Y denotes a group selected from --(CH.sub.2).sub.n-- (in which
n is 1 to 4), --O(CH.sub.2).sub.nO-- (in which n is 1 to 4).
[0038] Further, the liquid-crystal polymer used in the present
invention may be a polyalkylene terephthalate which partially does
not form an anisotropic molten phase in the same molecular chain,
in addition to the aforementioned components. In this case, the
number of carbons in the alkyl group is 2 to 4.
[0039] Among the above-described components, a further preferable
example is one containing, as the essential component(s), one or
two or more compounds selected from the group consisting of
naphthalene compounds, biphenyl compounds and para-substituted
benzene compounds. Among the p-substituted benzene compounds,
p-hydroxy benzoic acid, methyl hydroquinone and 1-phenylethyl
hydroquinone are especially preferred.
[0040] Examples of the compound having an ester formed functional
group as the components and the polyester forming an anisotropic
molten phase preferably used in the present invention are described
in JP-B 63-36633.
[0041] The aromatic polyester and polyester amide described above
generally show an inherent viscosity (I.V.) of at least about 2.0
dl/g, for example, about 2.0 to 10.0 dl/g when dissolved in
pentafluorophenol with a concentration of 0.1 wt % at 60.degree.
C.
[0042] The ratio of the thermoplastic resin (A) to the
liquid-crystal polymer (B) [(A)/(B)] in the present invention is
between 99/1 and 50/50, preferably between 99/1 and 80/20. When
(A)/(B) is higher than 99/1, the fiberized liquid-crystal polymer
does not show a substantial reinforcing effect and there is almost
no superiority to the properties of the thermoplastic resin (A)
alone. On the contrary, when (A)/(B) is lower than 50/50, the
matrix is the liquid-crystal polymer (B), so that the properties of
the thermoplastic resin can not be undesirably used to
advantage.
[0043] The halogen-containing organic compound (C) used in the
present invention may be any halogen-containing compound ordinarily
used as a flame retardant, for example, low-molecular halogenated
organic compounds such as a halogenated phenyl, a halogenated
diphenyl ether, a halogenated aromatic bisimide compound, a
halogenated aromatic epoxy compound and bisphenol A, a halogenated
polycarbonate, a halogenated benzyl acrylate, and a halogenated
polystyrene. As a halogen, bromine is generally preferable. The
especially preferable component (C) is a brominated
polycarbonate.
[0044] The amount of the halogen-containing organic compound (C) to
be blended is between 1.0 and 20 parts by weight, preferably
between 5.0 and 15 parts by weight, based on 100 parts by weight of
the resin component composed of 99 to 50 parts by weight of the
thermoplastic resin (A) and 1 to 50 parts by weight of the
liquid-crystal polymer (B). When the amount is less than 1.0 part
by weight, the effect of flame-retardancy is decreased. When it is
more than 20 parts by weight, the mechanical strength is
deteriorated.
[0045] The fluorine compound (D) used in the present invention is
not particularly limited so long as it is a synthetic compound
containing a fluorine atom in a molecule. Among them, a fluororesin
is preferable, and polytetrafluoroethylene is especially
preferable. Further, even if the fluororesin, the properties of the
powder thereof are greatly different depending on the production
method. Accordingly, a polymer as polymerized by an ordinary
polymerization method is more preferable because it becomes such a
fluororesin that is fiberized with a shearing force in the present
invention.
[0046] The amount of the fluorine compound (D) to be blended is
between 0.01 and 10 parts by weight, preferably between 0.05 and 5
parts by weight, based on 100 parts by weight of the resin
component composed of 99 to 50 parts by weight of the thermoplastic
resin (A) and 1 to 50 parts by weight of the liquid-crystal polymer
(B). When it is less than 0.01 part by weight, there is no effect
of preventing the melt drop of the thermoplastic resin as a flame
retardant aid. When it exceeds 10 parts by weight, the mechanical
strength is deteriorated.
[0047] In the present invention, it is efficient that the
liquid-crystal polymer (B) is previously micro-dispersed in the
matrix phase in order that the liquid-crystal polymer (B) is
oriented in the fibrous state in the matrix phase at an average
aspect ratio of at least 6 in the injection-molding. It is
therefore preferable that the components (E) and (F) are blended as
dispersion aids for micro-dispersing the liquid-crystal polymer (B)
in the matrix phase.
[0048] As the inorganic compound of phosphoric acid, phosphorous
acid and metal salts thereof (E) of the present invention,
metaphosphoric acid, orthophosphoric acid, metaphosphate,
orthophosphate and hydrogen orthophosphate are cited. As metals
constituting the metal salts, Group Ia and IIa elements of the
Periodic Table are preferable from the standpoint of the effect of
blending. For example, sodium metaphosphate, sodium phosphate,
monosodium phosphate, disodium phosphate, trisodium phosphate,
monobasic calcium phosphate, dibasic calcium phosphate, tribasic
calcium phosphate, mono-potassium phosphate, di-potassium phosphate
and tri-potassium phosphate are cited.
[0049] The amount of the component (E) to be blended is between
0.01 and 1.0 part by weight, preferably between 0.03 and 0.5 part
by weight, based on 100 parts by weight of the resin component
composed of 99 to 50 parts by weight of the thermoplastic resin (A)
and 1 to 50 parts by weight of the liquid-crystal polymer (B). When
it is less than 0.01 part by weight, an effect of fiberizing the
liquid-crystal polymer during the molding is decreased. When it
exceeds 1.0 part by weight, the mechanical strength is
deteriorated.
[0050] The phosphoric acid or phosphorous acid ester (F) of the
present invention includes
tetrakis(2,4-di-t-butylphenyl)-4,4'-biphenylene phosphonite,
bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol-diphosphit- e,
bis(2,4-di-t-butylphenyl)pentaerythritol-diphosphite and
tris(2,4-di-t-butylphenyl)phosphite. A phosphorous acid ester is
preferable, and a pentaerythritol-type phosphorous acid ester is
especially preferable.
[0051] The amount of the component (F) to be blended is between
0.01 and 3.0 parts by weight, preferably between 0.1 and 1.5 parts
by weight, based on 100 parts by weight of the resin component
composed of 99 to 50 parts by weight of the thermoplastic resin (A)
and 1 to 50 parts by weight of the liquid-crystal polymer (B). When
it is less than 0.01 part by weight, an effect of fiberizing the
liquid-crystal polymer during the molding is decreased. When it
exceeds 3.0 parts by weight, the mechanical strength is
deteriorated.
[0052] Next, the silane compound (G) in the present invention is a
component which is preferably added in order to prevent from
delamination on the surface of an article. Herein, the silane
compound (G) is one or two or more member(s) selected from
vinylalkoxysilane, aminoalkoxysilane and mercaptoalkoxysilane;
examples of vinylalkoxysilane include vinyltriethoxysilane,
vinyltrimethoxysilane and vinyltris(.beta.-methoxye- thoxy)silane;
examples of aminoalkoxysilane include
.gamma.-aminopropyltrimethoxysilane,
.gamma.-aminopropyltriethoxysilane,
.gamma.-aminopropylmethyldimethoxysilane,
N-(.beta.-aminoethyl)-.gamma.-a- minopropyltrimethoxysilane,
N-phenyl-.gamma.-amonipropyltrimethoxysilane; and mercaptane,
.gamma.-mercaptopropyltrimethoxysilane are cited.
[0053] The amount of the silane component (G) to be blended is 0.01
to 3.0 parts by weight, preferably 0.03 to 1.5 parts by weight,
based on 100 parts by weight of the resin component comprising 99
to 50 parts by weight of the thermoplastics resin (A) and 1 to 50
parts by weight of the liquid-crystal polymer (B). When the blended
amount of the component (G) is less than 0.01 part by weight, the
effect of improving delamination on the layer is hardly observed.
When the amount exceeds 3.0 parts by weight, elasticity modulus and
strength are deteriorated.
[0054] The thermoplastic resin composition of the present invention
can be blended with various types of fibrous, powder, plate or
hollow inorganic fillers according to the purposes of application.
Two or more of these may be used together.
[0055] As the fibrous filler, various fibers such as glass fibers,
carbon fibers, whiskers, metallic fibers, inorganic fibers and
mineral fibers can be used.
[0056] Examples of the powder or particulate filler include
silicates such as kaolin, clay, vermiculite, talc, calcium
silicate, aluminum silicate, feldspar powder, acid clay,
pyrophyllite clay, sericite, sillimanite, bentonite, glass powder,
glass beads, slate powder and silane; carbonates such as calcium
carbonate, chalk, barium carbonate, magnesium carbonate and
dolomite; sulfates such as barite powder, blanc fixe, precipitated
calcium sulfate, calcined gypsum and barium sulfate; hydroxides
such as hydrated alumina; oxides such as alumina, antimony oxide,
magnesia, titanium oxide, zinc oxide, silica, silica sand, quartz,
white carbon and diatomaceous earth; sulfides such as molybdenum
disulfide; metallic particles; and others.
[0057] Examples of tabular fillers include mica, glass flakes,
various metal foils and the like.
[0058] As the hollow filler, hollow glass beads and the like are
available.
[0059] The amount of the filler to be blended in the present
invention is between 15 and 100 parts by weight, especially
preferably between 30 and 75 parts by weight, based on 100 parts by
weight of the resin component composed of the component (A) and the
component (B).
[0060] In a method for obtaining the moldings of the present
invention, wherein the liquid-crystal polymer (B) is
micro-dispersed in the form of fibers having the average aspect
ratio of at least 6 in the matrix phase of the thermoplastic resin
(A), the kneading is conducted with a usual extruder and the
injection-molding is conducted at such a temperature that is more
than an incipient fluidization temperature of the liquid-crystal
polymer (B), preferably at least 10.degree. C. higher than the
incipient fluidization temperature thereof, and more than an
incipient fluidization temperature of the thermoplastic resin (A)
not forming an anisotropic molten phase, preferably at least
10.degree. C. higher than the incipient fluidization temperature
thereof, whereby the moldings are obtained by a shearing force in
the injection-molding. Since the moldings of the present invention
are obtained by using not the antimony compound but the fluorine
compound, the liquid-crystal polymer can be micro-dispersed in the
form of fibers even in the heat retention at the time of the
molding, and the mechanical properties are not influenced by the
molding conditions.
[0061] The moldings of the present invention become those having
excellent mechanical properties because the liquid-crystal polymer
plays a part of a fiber reinforcing material. The fiber herein
referred to is a liquid-crystal polymer having a fibrous or
needle-like structure with an average aspect ratio of at least 6,
and it includes also a product having a fibrous structure branched
from a fiberized trunk fiber.
[0062] The above-mentioned incipient fluidization temperature means
a temperature at which to show a fluidity by an external force when
a resin is heated. It can be measured by the method described
later.
EXAMPLES
[0063] Hereinafter, the present invention will be described in more
detail with reference to the following examples, but the present
invention is not limited to the examples. Evaluation methods are as
follows:
[0064] (Combustibility)
[0065] A combustion test piece having a thickness of 0.8 mm was
molded, and evaluated by a combustion test of UL94.
[0066] (Flexural Modulus)
[0067] A flexural modulus (MPa) of a bending test piece having a
thickness of 0.8 mm was measured according to ASTM D 790.
[0068] (Stability of Heat Retentivity)
[0069] Pellets were plasticized in a cylinder of a molding machine,
and then allowed to cool for 30 minutes. Thereafter, a flexural
modulus (MPa) of a test piece having the thickness of 0.8 mm was
measured according to ASTM D 790.
[0070] (Average Aspect Ratio of Fibrous Liquid-Crystal Polymer)
[0071] After the test piece used in the measurement of the flexural
modulus was cut to expose a plane parallel with a fluidity
direction, the cross section was mirror-polished, and the center of
its surface was observed by an electronic microscope to evaluate.
That is, the length/thickness of each of 50 arbitrarily selected
fibrous liquid-crystal polymers was measured. An apparently
observable length was regard as the length of fiber. As for
evaluation, an average aspect ratio of 6 or more is expressed as a
circle, while an average aspect ratio of less than 6 as a
cross.
[0072] (Test of Peeling Tape)
[0073] The test piece used in the measurement of flexural modulus
was used, and an adhesive tape having an area of 5 cm.sup.2 was
stuck on around the gate of the specimen. The tape was peeled off
at a constant rate, and an area of resin portion sticking to the
adhesive tape was measured. As for evaluation, a peel area of less
than 0.5 cm.sup.2 is expressed as a circle, a peel area of 0.5 to
1.0 cm.sup.2 as a triangle, and an area of more than 1.0 cm.sup.2
as a cross.
[0074] (Incipient Fluidization Temperature)
[0075] It was expressed in terms of a temperature at which the melt
viscosity was 48,000 poises when a sample resin, being heat-melted
at a heating rate of 4.degree. C./min, was extruded from a nozzle
having an inner diameter of 1 mm and a length of 10 mm under a load
of 100 kg/cm.sup.2, as measured using a capillary rheometer (Flow
Tester Model CFT-500, manufactured by Shimadzu Corp.).
Comparative Examples 1 to 3
[0076] 100 parts by weight of a resin component containing 78 parts
by weight of a polycarbonate resin (manufactured by Teijin
Chemicals Ltd., incipient fluidization temperature: 185.degree. C.)
and 22 parts by weight of a liquid-crystal polymer (Vectra A950,
manufactured by Polyplastics Co., Ltd., incipient fluidization
temperature: 265.degree. C.) were blended with the component (C)
and the component (E) or the component (F), and further, antimony
trioxide shown in Table 1 at ratios shown in Table 1. These were
melt-kneaded at a resin temperature of 300.degree. C. with a 30 mm
twin-screw extruder, and pelletized. Subsequently, the pellets were
formed into test pieces with an injection molding machine at a
molding temperature of 300.degree. C., and subjected to the
above-mentioned evaluation. The results are shown in Table 1.
Examples 1 to 4 and Comparative Examples 4 to 7
[0077] 100 parts by weight of a resin component containing a
polycarbonate resin (manufactured by Teijin Chemicals Ltd.,
incipient fluidization temperature: 185.degree. C.) and a
liquid-crystal polymer (Vectra A950, manufactured by Polyplastics
Co., Ltd., incipient fluidization temperature: 265.degree. C.) at
ratios shown in Table 1 were blended with the component (C), the
component (D) and the component (E) or the component (F) and
further, as required, the component (G) shown in Table 1 at ratios
shown in Table 1. These were melt-kneaded at a resin temperature of
300.degree. C. with a 30 mm twin-screw extruder, and pelletized.
Subsequently, the pellets were formed into test pieces with an
injection-molding machine at a molding temperature of 300.degree.
C., and subjected to the above-mentioned evaluation. The results
are shown in Table 1.
Examples 5 to 8
[0078] 100 parts by weight of a resin component containing a
polybutylene terephthalate resin (manufactured by Polyplastics Co.,
Ltd., (IV=1.0), incipient fluidization temperature: 237.degree. C.)
and a liquid-crystal polymer (Lodrun LC3000, manufactured by
Unitika Ltd., incipient fluidization temperature: 182.degree. C.)
at ratios shown in Table 2 were blended with the component (C), the
component (D), the component (E) or the component (F) and further,
as required, the component (G) shown in Table 2 at ratios shown in
Table 1. These were melt-kneaded at a resin temperature of
260.degree. C. with a 30 mm twin-screw extruder, and pelletized.
Subsequently, the pellets were formed into test pieces with an
injection-molding machine at a molding temperature of 250.degree.
C., and subjected to the above-mentioned evaluation. The results
are shown in Table 2.
[0079] The components used in the tables are as follows;
[0080] Polytetrafluoroethylene; Phostaflon TF1620, manufactured by
Hoechst Industry K.K.,
[0081] Phosphorous acid ester;
bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, and
[0082] Antimony tetraoxide; PATOX-L, manufactured by Nihon Seiko
Co., Ltd.
1TABLE 1 Com. Com. Com. Com. Com. Com. Com. Ex. 1 Ex. 1 Ex. 2 Ex. 3
Ex. 2 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 3 Ex. 4 Composition (a)
polybutylene terephthalate 78 78 78 78 67 79 73 78 73 78 78 (pts by
wt) (b) liquid crystal polymer 22 22 22 22 33 21 27 22 27 22 22 (c)
brominated polycarbonate 11 11 11 11 10 0.5 25 11 11 11 11 (d)
polytetrafluo-roethylene 0.2 1.5* 1.5* 0.5* 0.2 0.2 0.2 15 0.2 0.2
(e) calcium primary phosphate 0.05 0.05 0.05 0.05 0.05 0.05 0.05
0.05 0.05 (f) phosphorous acid ester 0.3 0.3
(g).gamma.-aminopropyl- 0.1 triethoxysilane Evaluation Flame
retardancy V-0 V-0 V-0 V-1 V-0 HB V-0 HB V-0 V-0 V-0 Flexural
modulus (MPa) 6000 5800 5700 5900 8000 6150 4800 6100 4600 5900
6000 Stability of heat retentivity 6100 2800 2600 2900 8100 6100
4500 6100 4200 6000 6100 (MPa) Average aspect ratio .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. .largecircle. Delamination .largecircle. .DELTA.
.DELTA. .DELTA. .DELTA. .DELTA. .DELTA. .DELTA. X .largecircle.
.largecircle. *antimony trioxide
[0083]
2 TABLE 2 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Composition (a) Polybutylene 66
76 76 76 (pts by wt) terephthalate (b) Liquid crystal 34 24 24 24
polymer (c) Brominated 14 15 15 15 polycarbonate (d)
Polytetrafluoro- 1.0 1.2 1.2 1.2 ethylene (e) Calcium primary 0.05
0.05 phosphate (f) Phosphorous acid ester (g)
.gamma.-aminopropyltri- 0.1 ethoxysilane Evaluation Flame
retardancy V-0 V-0 V-C V-C Flexural modulus (MPa) 6100 4700 5000
4900 Stability of heat 5900 4500 4700 4700 retentivity (MPa)
Average aspect ratio .smallcircle. .smallcircle. .smallcircle.
.smallcircle. Delamination .DELTA. .DELTA. .DELTA. .DELTA.
* * * * *