U.S. patent application number 09/782025 was filed with the patent office on 2001-10-18 for polyamide composition.
Invention is credited to Miyoshi, Takaaki, Nakahashi, Junichi.
Application Number | 20010031831 09/782025 |
Document ID | / |
Family ID | 18560962 |
Filed Date | 2001-10-18 |
United States Patent
Application |
20010031831 |
Kind Code |
A1 |
Miyoshi, Takaaki ; et
al. |
October 18, 2001 |
Polyamide composition
Abstract
The present invention relates to a polyamide composition
comprising (A) polyamide, (B) polyphenylene ether, and (C) an
ethylene-.alpha.-olefin copolymer prepared using a single site
catalyst. The resin composition of the present invention can
provide a polyamide composition having excellent impact resistance
and excellent surface smoothness, and displaying only small
dimensional changes after water absorption.
Inventors: |
Miyoshi, Takaaki;
(Kimitsu-shi, JP) ; Nakahashi, Junichi;
(Kimitsu-shi, JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
18560962 |
Appl. No.: |
09/782025 |
Filed: |
February 14, 2001 |
Current U.S.
Class: |
525/138 ;
525/141 |
Current CPC
Class: |
C08L 77/06 20130101;
C08L 77/06 20130101; C08L 77/02 20130101; C08L 77/00 20130101; C08L
23/08 20130101; C08L 77/00 20130101; C08L 77/00 20130101; C08L
77/02 20130101; C08L 77/02 20130101; C08L 77/06 20130101; C08L
77/02 20130101; C08L 23/00 20130101; C08L 71/00 20130101; C08L
71/00 20130101; C08L 71/00 20130101; C08L 77/00 20130101; C08L
23/00 20130101; C08L 23/00 20130101; C08L 2666/02 20130101; C08L
2666/02 20130101; C08L 2666/02 20130101; C08L 71/12 20130101; C08L
77/00 20130101; C08L 77/06 20130101; C08L 71/12 20130101 |
Class at
Publication: |
525/138 ;
525/141 |
International
Class: |
C08G 073/02; C08G
065/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 15, 2000 |
JP |
2000-37005 |
Claims
What is claimed is:
1. A composition comprising: (A) 50 to 95% by weight of polyamide
based on the total of components (A) and (B); (B) 50 to 5% by
weight of polyphenylene ether based on the total of components (A)
and (B); and (C) 1 to 30 parts by weight, based on 100 parts by
weight of the total of components (A) and (B), of an
ethylene-.alpha.-olefin copolymer prepared using a single site
catalyst and/or an ethylene-.alpha.-olefin copolymer prepared using
a single site catalyst and modified with one or more compounds
selected from the group consisting of .alpha., .beta.-unsaturated
dicarboxylic acid and derivatives thereof.
2. The composition according to claim 1, wherein component (A) of
polyamide forms a continuous phase, and components other than
component (A) form dispersed phases which have a number-average
distribution diameter of 10 .mu.m or less.
3. The composition according to claim 1 or 2, wherein component (C)
of an ethylene-.alpha.-olefin copolymer has a molecular weight
distribution (weight-average molecular weight/number-average
molecular weight) of 3 or less.
4. The composition according to claims 1 to 3, wherein the single
site catalyst used for the preparation of component (C) of the
ethylene-.alpha.-olefin copolymer contains one or more catalysts
containing 1 or 3 cyclopentadienyl or substituted cyclopentadienyl
molecules.
5. The composition according to claims 1 to 4, wherein an ethylene
unit content of component (C) of the ethylene-.alpha.-olefin
copolymer is 30 to 95% by weight.
6. The composition according to claims 1 to 5, wherein an
electroconductive filler is incorporated as component (D) in an
amount of less than 10 parts by weight based on 100 parts by weight
of the total of components (A), (B) and (C).
7. The composition according to claims 1 to 6, wherein a block
copolymer of an aromatic vinyl compound and a conjugated diene
compound and/or a hydrogenated product thereof is incorporated as
component (E) in an amount of less than 30 parts by weight based on
100 parts by weight of the total of components (A), (B) and
(C).
8. The composition according to claim 7, wherein component (E) is a
block copolymer of an aromatic vinyl compound and a conjugated
diene compound having a content of an aromatic vinyl compound of 15
to 65% by weight and a number-average molecular weight using a
polystyrene standard of 80,000 to 300,000.
9. The composition according to claims 1 to 8, wherein the
composition contains at least one compatible agent selected from
the group consisting of a copolymer comprising an aromatic vinyl
compound and .alpha., .beta.-unsaturated dicaroxylic acid and/or
derivatives thereof, maleic anhydride, fumaric acid, citric acid
and malic acid.
10. The composition according to claims 1 to 9, wherein a part or
all of component (B) of polyphenylene ether is modified
polyphenylene ether obtained by reacting one or more compounds
selected from the group consisting of maleic anhydride, fumaric
acid, glycidyl acrylate and glycidyl methacrylate with non-melted
polyphenylene ether in the presence or absence of a radical
initiator at a temperature from 100.degree. C. to a glass
transition point of polyphenylene ether.
11. The composition according to claims 6 to 10, wherein component
(D) of the electroconductive filler is an electroconductive carbon
black.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a composition having
excellent impact strength and surface smoothness and displaying
only small dimensional changes after water absorption. The
composition of the present invention is applicable to a wide range
of uses such as automobile parts, electric and electronic parts,
and mechanical parts.
BACKGROUND ART
[0002] A polymer alloy comprising a polyamide and a polyphenylene
ether can become a very useful material by being incorporated with
an elastomer, and conventionally has been applied to various
uses.
[0003] For example, Japanese Patent Application Laid-Open No.
61-204262 discloses a composition comprising polyamide,
polyphenylene ether and a styrene type hydrocarbon polymer
block-conjugated diene type elastomer block copolymer. Further,
Japanese Patent Application Laid-Open Nos. 62-1289350, 2-135246 and
5-339496 disclose that a rubbery polymer composition containing
polyphenylene ether, polyamide, an ethylene-.alpha.-olefin
copolymer and the like has improved impact resistance.
[0004] However, the above prior art has been effective at improving
the impact strength of compositions, but there is a big problem
that a continuous phase of the polyamide absorbs water from the air
resulting in a great size change of the molded piece.
[0005] In recent days, there has been an increasing demand for
electroconductive materials, especially integrated circuit tray
materials and electrostatically painted external trim parts for
automobiles and motorcycles. Namely, they have been required to
have high electroconductivity in addition to impact resistance,
surface smoothness and small dimensional changes after water
absorption.
[0006] As prior art relating to electroconductive resin
compositions, Japanese Patent Application Laid-Open No. 8-48869
discloses that an electroconductive resin composition having a low
melt viscosity and high impact resistance can be obtained by
incorporating an electroconductive carbon black into a
compatibilized polyphenylene ether-polyamide base resin. Further,
Japanese Patent Application Laid-Open No. 10-310695 discloses an
electroconductive composition comprising polyethylene ether, an
impact modifying polymer containing ethylenically unsaturated
structural units in a specific amount or more, various polyamides
and an electroconductive carbon black.
[0007] However, the electroconductivity values in the above prior
documents are measured between fractured surfaces of a broken off
molded piece. In other words, it is measured by totally ignoring
influences of the skin layer of the molded piece. Generally, such a
process for charging a molded article wherein the molded article is
broken off and then a voltage is applied thereto is not actually
practical. The electroconductivity measured according to such a
method is not practical at all. Moreover, the compositions obtained
by the prior art are less worth using because of their inferior
appearance (surface smoothness).
[0008] In general, the electroconductivity and the surface
smoothness are contradictory properties. Namely, materials having
higher surface smoothness tend to have inferior
electroconductivity.
[0009] The electroconductivity is measured by applying a silver
paste to two faces facing each other and measuring a resistance
value therebetween. Accordingly, materials having higher surface
smoothness have a lower contact area with the silver paste so that
the resistance value of the materials tend to be higher.
[0010] However, there has been demanded materials exhibiting high
electroconductivity without deteriorating impact resistance,
surface smoothness and the small dimensional changes after water
absorption, wherein the electroconductivity is measured without
breaking off a molded piece.
[0011] On the other hand, Japanese Patent Application Laid-Open No.
2-201811 discloses a resin composition comprising polyphenylene
ether, polyamide and an electroconductive carbon black wherein the
electroconductive carbon black is introduced mainly in the
polyamide, and it teaches that the electroconductivity (surface
resistivity) is achieved by a method wherein a piece is not broken
off from a molded article. However, according to this prior art,
properties important to the composition (impact resistance, surface
smoothness and small dimensional changes after water absorption)
are greatly deteriorated so that the resultant composition is less
worth using.
[0012] As described above, none of prior art has completely
satisfied market demands for a composition having excellent impact
resistance and surface smoothness and displaying only small
dimensional changes after water absorption. In addition, it has
been very difficult to impart to compositions high
electroconductivity which can be achieved by a method wherein a
piece is not broken off from a molded article.
SUMMARY OF THE INVENTION
[0013] An object of the present invention is to provide a
composition having excellent impact resistance and surface
smoothness and displaying only small dimensional changes after
water absorption. The term "small dimensional changes after water
absorption" herein means that a molded piece prepared using the
composition of the present invention exhibits the same water
absorption as those prepared using other compositions, but displays
smaller changes in dimension than them.
[0014] Another object of the present invention is to provide a
composition having excellent electroconductivity in addition to
excellent impact resistance, excellent surface smoothness and small
dimensional changes after water absorption.
[0015] The present inventors have made extensive and intensive
studies to avoid the above-mentioned problems and have found that a
composition comprising polyphenylene ether, polyamide, an
ethylene-.alpha.-olefin copolymer prepared using a single site
catalyst has excellent impact resistance, excellent surface
smoothness and small dimensional changes after water absorption. As
a result, the present invention has been accomplished.
[0016] Namely, the present invention relates to a composition
having excellent impact resistance and surface smoothness and
displaying only small dimensional changes after water absorption,
which comprises:
[0017] (A) 50 to 95% by weight of polyamide based on the total of
components (A) and (B);
[0018] (B) 50 to 5% by weight of polyphenylene ether based on the
total of components (A) and (B); and
[0019] (C) 1 to 30 parts by weight, based on 100 parts by weight of
the total of components (A) and (B), of an ethylene-.alpha.-olefin
copolymer prepared using a single site catalyst and/or an
ethylene-.alpha.-olefin copolymer prepared using a single site
catalyst and modified with one or more compounds selected from the
group consisting of .alpha., .beta.-unsaturated dicarboxylic acid
and derivatives thereof.
BEST MODE FOR CARRYING OUT THE INVENTION
[0020] Hereinafter, the present invention is illustrated in more
detail.
[0021] As component (A) of polyamide usable in the present
invention, any polyamide can be employed as long as it contains an
amide bond {--NH--C(.dbd.O)--} in the polymer main chain. In
general, polyamides can be obtained by ring opening polymerization
of lactams, polycondensation of diamine and dicarboxylic acid,
polycondensation of aminocarboxylic acid, and the like, but
preparation methods are not limited thereto.
[0022] As the diamine, aliphatic diamine, alicyclic diamine and
aromatic diamine can be exemplified. Specifically, they include
tetramethylenediamine, hexamethylenediamine,
undecamethylenediamine, dodecamethylenediamine,
tridecamethylenediamine, 2,2,4-trimethyl hexamethylenediamine,
2,4,4-trimethyl hexamethylenediamine, 5-methyl
nanomethylenediamine, 1,3-bisaminomethyl cyclohexane,
1,4-bisaminomethyl cyclohexane, m-phenylenediamine,
p-phenylenediamine, m-xylylenediamine, p-xylylenediamine and the
like.
[0023] As the dicarboxylic acid, aliphatic dicarboxylic acid,
alicyclic dicarboxylic acid and aromatic dicarboxylic acid can be
exemplified. Specifically, they include adipic acid, suberic acid,
azelaic acid, sebacic acid, dodecanoic diacid, 1,1,3-tridecanoic
diacid, 1,3-cyclohexane dicarboxylic acid, terephthalic acid,
isophthalic acid, naphthalenedicarboxylic acid, dimer acid, and the
like.
[0024] As the lactams, there can be specifically exemplified
.epsilon.-caprolactam, enantholactam, .omega.-laurolactam, and the
like.
[0025] Further, as aminocarboxylic acid, there can be specifically
exemplified .epsilon.-aminocaproic acid, 7-aminoheptanoic acid,
8-aminooctanoic acid, 9-aminononanoic acid, 11-aminoundecanoic
acid, 12-aminododecanoic acid, 13-aminotridodecanoic acid, and the
like.
[0026] In the present invention, there can be employed any of
copolymerized polyamides obtained by subjecting the above-listed
lactams, diamines, dicarboxylic acids and aminocarboxylic acids
individually or in combination to polycondensation. Further, there
can be advantageously used polyamides obtained by polymerizing the
above-listed lactams, diamines, dicarboxylic acids and
aminocarboxylic acids in a polymerization reactor to be a low
molecular weight oligomer and making the oligomer polymeric using
an extruder and the like.
[0027] The polyamides most advantageously usable in the present
invention include polyamide 6, polyamide 66, polyamide 46,
polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide
6/66, polyamide 6/612, polyamide MXD6 (MXD: m-xylylenediamine),
polyamide 6/MXD6, polyamide 66/MXD6, polyamide 6T, polyamide 6I,
polyamide 6/6T, polyamide 6/6I, polyamide 66/6T, polyamide 66/6I,
polyamide 6/6T/6I, polyamide 66/6T/6I, polyamide 6/12/6T, polyamide
66/12/6T, polyamide 6/12/6I, polyamide 66/12/6I, and the like.
Polyamides obtained by copolymerizing a plurality of polyamides
using an extruder and the like can be also employed. These
polyamides may be used alone or in combination.
[0028] A number-average molecular weight of the polyamides used in
the present invention is preferably 5,000 to 100,000, more
preferably 10,000 to 30,000. The polyamides used in the present
invention may be a mixture of plural polyamides having different
molecular weights. For example, there can be exemplified a mixture
of a low molecular weight polyamide having a number-average
molecular weight of 10,000 or less and a polymeric polyamide having
a number-average molecular weight of 30,000 or more; a mixture of a
low molecular weight polyamide having a number-average molecular
weight of 10,000 or less and a common polyamide having a
number-average molecular weight of approximately 15,000; and the
like. However, the polyamides used in the present invention are not
limited to the above examples.
[0029] Further, different types of polyamides having different
molecular weights may be mixed.
[0030] The end groups of the polyamide are involved in a reaction
with polyphenylene ether. Polyamides usually contain an amino
group, and a carboxyl group as an end group. In general, when a
concentration of carboxyl groups exceeds that of amino groups, the
impact resistance is decreased and the fluidity is improved. In
contrast, when a concentration of amino groups exceeds that of
carboxyl groups, the impact resistance is improved and the fluidity
is decreased. A ratio of amino groups/carboxyl groups is preferably
9/1 to 1/9, more preferably 8/2 to 1/9, further more preferably 6/4
to 1/9. A concentration of end amino groups is preferably at least
10 milliequivalent/kg, more preferably 30 milliequivalent/kg or
more.
[0031] The amino end groups may be prepared in accordance with the
conventional methods known to the skilled in the art. For example,
they are prepared by adding diamines, dicarboxylic acids or
monocarboxylic acid upon polymerizing polyamides. The polyamides
used in the present invention may be a mixture of plural polyamides
having different concentrations of end groups.
[0032] Further, for the purpose of improving thermal stability of
the polyamides, there can be used a metallic stabilizer as
represented by the following known formula (1):
M.sub.n.sup.y+X.sub.n.multidot.y/z.sup.z- (1)
[0033] wherein M represents a metallic ion selected from the group
consisting of copper, potassium, nickel, tin and cerium; X
represents an ion group selected from the group consisting of a
halogenated ion and a carboxylated ion; n is an integer of 1 to 6;
y is an integer representing a positive ionic charge of M; and z is
an integer representing a negative ionic charge of X.
[0034] Specific examples of the metallic stabilizer include CuI,
CuCl.sub.2, copper acetate, potassium iodide, cerium stearate, and
the like. These components may be used in combination. A preferable
amount of the metallic stabilizer to be incorporated is 0.001 to 1
part by weight based on 100 parts by weight of polyamide.
[0035] Component (B) of polyphenylene ether used in the present
invention is a homopolymer or a copolymer comprises structural
units represented by the following formula (2): 1
[0036] wherein R.sub.1 and R.sub.4 each independently represent
hydrogen, halogen, primary or secondary lower alkyl, phenyl,
haloalkyl, aminoalkyl, oxy-hydrocarbon, or oxy-halohydrocarbon
(provided that at least two carbon atoms separate a halogen atom
and an oxygen atom); and R.sub.2 and R.sub.3 each independently
represent hydrogen, halogen, primary or secondary lower alkyl,
phenyl, haloalkyl, oxy-hydrocarbon or oxy-halohydrocarbon (provided
that at least two carbon atoms separate a halogen atom and an
oxygen atom).
[0037] A reducing viscosity of the homopolymer and/or the copolymer
(measured: 0.5 g/dl, a chloroform solution, 30.degree. C.) is
preferably 0.15 to 0.70, more preferably 0.20 to 0.60, and even
more preferably 0.40 to 0.55. There is no problem in blending two
or more polyphenylene ethers having different reducing viscosity
for use.
[0038] Specific examples of polyphenylene ether used in the present
invention include poly(2,6-dimethyl-1,4-phenylene ether),
poly(2-methyl-6-ethyl-1,4-phenylene ether),
poly(2-methyl-6-phenyl-1,4-ph- enylene ether),
poly(2,6-dichloro-1,4-phenylene ether), and the like. Further, they
include polyphenylene ether copolymers prepared by copolymerizing
2,6-dimethylphenol with other phenols such as 2,3,6-trimethylphenol
and 2-methyl-6-butylphenol. Of these,
poly(2,6-dimethyl-1,4-phenylene ether) and a copolymer of
2,6-dimethylphenol and 2,3,6-trimethylphenol are preferable. More
preferable is poly(2,6-dimethyl-1,4-phenylene ether).
[0039] The production method of polyphenylene ether used in the
present invention is not particularly limited as long as it is
prepared according to the well known methods. For example,
polyphenylene ether used in the present invention can be easily
prepared according to the method disclosed in U.S. Pat. No.
3,306,874 wherein oxidative polymerization of, for instance,
2,6-dimethylphenol is carried out using a complex of primary copper
chloride and amine as a catalyst. In addition, the polyphenylene
ether can be easily prepared according to the methods disclosed in
U.S. Pat. Nos. 3,306,875, 3,257,357 and 3,257,358, Japanese Patent
Publication No. 52-17880, and Japanese Patent Application Laid-Open
Nos. 50-51197 and 63-152628.
[0040] Further, polyphenylene ether (B) used in the present
invention may be entirely or partially modified. The modified
polyphenylene ether herein indicates those modified by at least one
modifier compound containing in the molecular structure at least
one carbon-carbon double or triple bond and at least one carboxylic
acid, acid anhydride, amino, hydroxyl or glycidyl group.
[0041] The modified polyphenylene ether is prepared according
to:
[0042] (1) a method comprising reacting non-melted polyphenylene
ether and a modifier compound in the presence or absence of a
radical initiator at a temperature from 100.degree. C. to the glass
transition point of polyphenylene ether;
[0043] (2) a method comprising reacting polyphenylene ether and a
modifier compound by melt mixing in the presence or absence of a
radical initiator at a temperature from the glass transition point
of polyphenylene ether to 360.degree. C.; and
[0044] (3) a method comprising reacting polyphenylene ether and a
modifier compound in a solution in the presence or absence of a
radical initiator at a temperature lower than the glass transition
point of polyphenylene ether.
[0045] Any one of the above-mentioned methods can be employed. Of
these, preferred is methods (1) and (2), and most preferred is
method (1).
[0046] Hereinafter, the at least one modifier compound containing
in the molecular structure, at least one carbon-carbon double or
triple bond and at least one carboxylic acid, acid anhydride,
amino, hydroxyl or glycidyl group is specifically described.
[0047] As a modifier compound containing in the molecule a
carbon-carbon double bond, a carboxylic acid group and an acid
anhydride group at the same time, there can be exemplified maleic
acid, fumaric acid, chloromaleic acid,
cis-4-cyclohexene-1,2-dicarlboxylic acid and acid anhydride
thereof. Particularly, fumaric acid, maleic acid, maleic anhydride
are preferred. Fumaric acid and maleic anhydride are especially
preferred. Further, monoester or diester type of unsaturated
dicarboxylic acid can be used in the present invention.
[0048] As a modifier compound containing in the molecule a
carbon-carbon double bond and a glycidyl group at the same time,
there can be exemplified allyl glycidyl ether, glycidyl acrylate,
glycidyl methacrylate, epoxidized natural oil, and the like. Of
these, glycidyl acrylate and glycidyl methacrylate are particularly
preferred.
[0049] As a modifier compound containing in the molecule a
carbon-carbon double bond and a hydroxyl group at the same time,
there can be exemplified unsaturated alcohol represented by the
general formula, C.sub.nH.sub.2n-3OH (wherein n is a positive
integer) such as allyl alcohol, 4-penten-1-ol, 1,4-pendadiene-3-ol;
unsaturated alcohol represented by the general formulas, for
example, C.sub.nH.sub.2n-5OH and C.sub.nH.sub.2n-7OH (wherein n is
a positive integer); and the like.
[0050] The above-listed modifier compounds may be used alone or in
combination.
[0051] Further, in the polyphenylene ether (B) used in the present
invention, an organic solvent derived from a polymerization solvent
may remain in an amount of less than 5% by weight based on 100
parts by weight of polyphenylene ether. The organic solvent derived
from the polymerization solvent is difficult to be completely
removed at a drying step after polymerization, and it usually
remains in an amount from several hundreds ppm to several percents.
Herein, the organic solvent derived from a polymerization solvent
includes at least one of toluene, an isomer of xylene,
ethylbenzene, alcohols having 1 to 5 carbon atoms, chloroform,
dichloromethane, chlorobenzene, dichlorobenzene and the like.
[0052] Moreover, the polyphenylene ether used in the present
invention includes those containing polystyrene (including
syndiotactic polystyrene) and/or high impact polystyrene in an
amount of less than 400 parts by weight based on 100 parts by
weight of polyphenylene ether.
[0053] The proportion of polyamide (A)/polyphenylene ether (B) is
preferably in the range of 50/50 to 95/5. When an amount of
polyamide is under 50% by weight, the surface smoothness is
deteriorated. On the other hand, when it is over 95% by weight, the
impact resistance is deteriorated.
[0054] Component (C) usable in the present invention includes
commercially available ethylene-.alpha.-olefin copolymers, i.e., an
ethylene-.alpha.-olefin copolymer prepared using a single site
catalyst and/or an ethylene-.alpha.-olefin copolymer prepared using
a single site catalyst and modified with one or more compounds
selected from the group consisting of .alpha., .beta.-unsaturated
dicarboxylic acid and derivatives thereof, which copolymers are
disclosed in Japanese Patent Publication No. 4-12283 and Japanese
Patent Application Laid-Open Nos. 60-35006, 60-35007, 60-35008,
5-155930 and 3-163088 and U.S. Pat. No. 5,272,236. The single site
catalyst employed for the preparation of such a copolymer is such
that exhibits uniform activity, for instance, a metallocene
catalyst containing 1 to 3 molecules of cyclopentadienyl or
substituted cyclopentadienyl and a geometrically controlled
catalyst.
[0055] The ethylene-.alpha.-olefin copolymer (C) used in the
present invention is polymerized according to vapor phase
polymerization or solution polymerization disclosed in the
above-mentioned published patents and patent applications. Among
them, preferred polymerization method is solution polymerization.
Monomers copolymerizable with ethylene units upon the
polymerization include an aliphatic substituted vinyl monomer such
as propylene, butene-1, pentene-1, 4-methylpentene-1, hexene-1,
heptene-1, octene-1, nonene-1, decene-1, undecene-1, dodecene-1,
tridecene-1, tetradecene-1, pentadecene-1, hexadecene-1,
heptadecene-1, octadecene-1, nonadecene-1, eicosene-1 and
isobutylene; an aromatic vinyl monomer such as styrene and
substituted styrene; an ester vinyl monomer such as vinyl acetate,
ester acrylate, ester methacrylate, ester glycidylacrylate, ester
glycidylmethacrylate and ester hydroxyethylmethacrylate; a
nitrogen-containing vinyl monomer such as acrylamide, allylamine,
vinyl-p-aminobenzene and acrylonitrile; and diene such as
butadiene, cyclopentadiene, 1,4-hexadiene and isoprene; preferably
a copolymer of ethylene and at least one C.sub.3-20 .alpha.-olefin,
more preferably a copolymer of ethylene and at least one C.sub.3-16
.alpha.-olefin, most preferably a copolymer of ethylene and at
least one C.sub.3-12 .alpha.-olefin.
[0056] The molecular weight of the ethylene-.alpha.-olefin
copolymer used in the present invention is preferably 10,000 or
more, more preferably 10,000 to 100,000, further more preferably
20,000 to 60,000, in a number-average molecular weight (Mn)
measured using 1,2,4-trichlorobenzene as a solvent and an
apparatus, 150c-GPC manufactured by Waters Corp., and a polystyrene
standard.
[0057] The molecular weight distribution of the
ethylene-.alpha.-olefin copolymer measured according to the above
GPC (weight-average molecular weight/number-average molecular
weight: Mw/Mn) is preferably 3 or less, more preferably 1.8 to
2.7.
[0058] The ethylene-.alpha.-olefin copolymer prepared using a
single site catalyst, which is used in the present invention,
preferably contains ethylene units in an amount of 30 to 95% by
weight based on the total amount of the ethylene-.alpha.-olefin
copolymer.
[0059] In the present invention, whole or a part of the
ethylene-.alpha.-olefin copolymer may be a modified with at least
one of .alpha., .beta.-unsaturated dicarboxylic acid and
derivatives thereof. Specific examples of the .alpha.,
.beta.-unsaturated dicarboxylic acid and derivatives thereof
include maleic acid, fumaric acid, maleic anhydride, and fumaric
anhydride. Of these, maleic anhydride is particularly
preferred.
[0060] In the present invention, it is essential to prepare
ethylene-.alpha.-olefin copolymers to be used with a single site
catalyst. If an ethylene-.alpha.-olefin copolymer prepared using a
catalyst other than a single site catalyst is employed, the
fluidity, electroconductivity and surface smoothness of the
resultant composition are unpreferably deteriorated.
[0061] A preferable amount of the ethylene-.alpha.-olefin copolymer
prepared using a single site catalyst of the present invention
and/or the ethylene-.alpha.-olefin copolymer modified with at least
one of .alpha., .beta.-unsaturated dicarboxylic acid and
derivatives thereof is 1 to 30 parts by weight based on 100 parts
by weight of the total of polyamide and polyphenylene ether. The
amount of less than 1 part by weight deteriorates impact
resistance. The amount of more than 30 parts by weight deteriorates
other properties (for example, thermal resistance).
[0062] The composition of the present invention preferably consists
of a continuous phase of polyamide and dispersed phases of the
other components having a number-average dispersion diameter of 10
.mu.m or less, preferably 5 .mu.m or less. The number-average
dispersion diameter herein means a dispersion diameter of a
dispersed phase obtained by observing the central part of the
molded piece of the composition from the direction perpendicular to
the flow direction. Specifically, the number-average dispersion
diameter can be obtained by immersing a molded piece in a 10% by
weight solution of phosphotungstic acid [12 tungsten (VI)
phosphorous acid hydrate: H.sub.3(PW.sub.12O.sub.40).nH.sub.2O] for
4 hours, selectively staining polyamide portions with
phosphotungstic acid, photographing the composition with a
transmission electron microscope, and measuring portions other than
polyamide portions, i.e., dispersion diameters of the dispersed
phases from the obtained image to average them. Further, when the
dispersion configuration is not spherical, the dispersion diameter
is expressed by a circle equivalent diameter. For example, in case
of an oval, a circle equivalent diameter is obtained based on an
area of the oval obtained from a minor axis and a major axis and
the resultant circle equivalent diameter is defined as a dispersion
diameter.
[0063] In the present invention, an electroconductive filler may be
incorporated as component (D) into 100 parts by weight of the total
of components (A), (B) and (C) in an amount of less than 10 parts
by weight. By incorporating the electroconductive filler
additionally, a composition becomes excellent not only in impact
resistance and surface smoothness and displays only small
dimensional changes after water absorption, but also becomes
superior in electroconductivity.
[0064] The electroconductive filler used in the present invention
includes all types of fillers added to impart electroconductivity
to a resin, specifically a powder filler, a flake filler and a
fiber filler.
[0065] As the powder filler, a carbon black, graphite and the like
are suitably used.
[0066] As the flake filler, aluminum flake, nickel flake, nickel
coated mica and the like are suitably used.
[0067] Further, as the fiber filler, carbon fiber, carbon coated
ceramic fiber, carbon whisker, metallic fiber such as aluminum
fiber, copper fiber, brass fiber and stainless fiber and the like
are suitably used.
[0068] Of these, carbon fiber, carbon black and graphite are
particularly suitable, with carbon black being most suitable.
[0069] The carbon fiber usable in the present invention includes
all types of fibers obtained by calcining and carbonating fibers
prepared using polyacrylonitrile (PAN), pitch or the like as a raw
material in an inert atmosphere at a temperature between
1,000.degree. and 3,500.degree. C. The fiber diameter is preferably
1 to 30 .mu.m, more preferably 5 to 20 .mu.m.
[0070] The carbon black usable in the present invention includes
all types of carbon blacks generally used for imparting
electroconductivity. Preferred carbon blacks include an acetylene
black obtained by complete combustion of acetylene gas, Ketjen
black obtained by conducting incomplete combustion according to the
furnace process using crude oil as a raw material, and the like,
but are not limited thereto.
[0071] Particularly preferred is a carbon black having a
dibutylphthalate (DBP) oil absorption of 70 ml/100 mg or more,
preferably 100 ml/100 mg or more, more preferably 150 ml/100 mg or
more. The DBP oil absorption herein indicates a value measured
according to ASTM D2414. Further, a carbon black having a volatile
content of less than 1.0% by weight is more preferred.
[0072] The electroconductive carbon blacks commercially available
include Ketjen black EC-600JD and Ketjen black EC, which are
manufactured by Ketjen Black International Co., Ltd. Further, a
carbon fibril available from Hyperion Catalyst can be used.
[0073] The graphite usable in the present invention includes not
only those obtained by heating Kilkenny coal or pitch in an arc
oven but also natural graphite. The weight-average particle size of
the graphite is preferably 1 to 100 .mu.m, more preferably 5 to 50
.mu.m.
[0074] These electroconductive fillers may be improved in adhesion
property with a resin and handling ability using various
conventional coupling agents and/or converging agents.
[0075] In the present invention, a block copolymer of an aromatic
vinyl compound and a conjugated diene compound and/or a
hydrogenated compound thereof may be added as component (E) in an
amount of less than 30 parts by weight based on 100 parts by weight
of the total of components (A), (B) and (C). By adding the block
copolymer of the aromatic vinyl compound and the conjugated diene
compound and/or the hydrogenated compound thereof, a composition
having an improved balance between impact resistance and surface
smoothness can be obtained.
[0076] The block copolymer of the aromatic vinyl compound and the
conjugated diene compound herein used contains one, preferably two
or more polymer blocks comprising mainly aromatic vinyl compounds
and at least one polymer block comprising mainly conjugated diene
compounds. The weight proportion of aromatic vinyl
compounds/conjugated diene compounds in the block copolymer of the
aromatic vinyl compound and the conjugated diene compound is
desirably 10/90 to 90/10, more desirably 15/85 to 80/20, further
more desirably 15/85 to 65/35. Two or more block copolymers having
different weight proportions of the aromatic vinyl compounds to the
conjugated diene compounds may be blended. Further, a block
copolymer containing mineral oil and the like may be employed.
[0077] As the aromatic vinyl compound, one or more compounds
selected from styrene, .alpha.-methylstyrene, vinyl toluene, and
the like are used. Among them, styrene is most preferably used.
[0078] As the conjugated diene compound, one or more compounds
selected from butadiene, isoprene, piperine, 1,3-pentadiene, and
the like are used. Among them, butadiene, isoprene and the
combination thereof are preferably used.
[0079] The molecular structure of the block copolymer may be in the
form of a linear chain, a branch or a radiation, or in combinations
thereof. When butadiene is used as the conjugated diene compound, a
1,2-vinyl content or the total content of a 1,2-vinyl content and a
3,4-vinyl content in the microstructure of polybutadiene blocks is
preferably 5 to 80%, more preferably 10 to 70%.
[0080] The hydrogenated compound of the block copolymer of the
aromatic vinyl compound and the conjugated diene compound is
obtained by hydrogenating the above-mentioned block copolymer of
the aromatic vinyl compound and the conjugated diene compound to
adjust the content of aliphatic double bonds of the polymer block
comprising mainly diene compounds to be in the range of more than
0% and 100% or less.
[0081] A molecular weight of the block copolymer of the aromatic
vinyl compound and the conjugated diene compound and/or the
hydrogenated compound thereof used in the present invention is
preferably 10,000 to 500,000, most preferably 80,000 to 300,000 in
a number-average molecular weight (Mn) which is measured using a
chloroform as a solvent at 40.degree. C. with a GPC apparatus
(SYSTEM 21) manufactured by Showa Denko K.K. according to a
polystyrene standard.
[0082] The block copolymer of the aromatic vinyl compound and the
conjugated diene compound and/or the hydrogenated compound thereof
may be used in combination of two or more different types. Further,
those modified with a carboxylic acid group, an acid anhydride
group, an amino group, a hydroxyl group, a glycidyl group or the
like can be advantageously employed.
[0083] The existence morphology of component (E), the copolymer of
aromatic vinyl compounds and conjugated diene compound and/or the
hydrogenated compound thereof, in the composition is not
particularly limited, but it is preferable that it exists in
component (B), polyphenylene ether.
[0084] A preferable proportion of each component in the composition
of the present invention is that the proportion of component (A),
polyamide,/component (B), polyphenylene ether, is 50/50 to 95/5,
and the proportion of component (C), one or more modifier compounds
selected from the ethylene-.alpha.-olefin copolymer prepared using
a single site catalyst and/or .alpha., .beta.-unsaturated
dicarboxylic acid and derivatives thereof, is 1 to 30 parts by
weight based on 100 parts by weight of the total of component (A)
polyamide and component (B) polyphenylene ether.
[0085] In the present invention, a compatible agent may be used
upon the preparation of the composition. The compatible agent is
used mainly for the purpose of improving physical properties of a
polyamide-polyphenylene ether mixture. The compatible agents usable
in the present invention are polyfunctional compounds interacting
with either polyphenylene ether, polyamide or both of them. The
interaction may be chemical (e.g., grafting) or physical (e.g.,
changing surface characteristics of dispersed phases). Whichever
compatible agent is employed, the resultant polyamide-polyphenylene
ether mixture exhibits improved compatibility.
[0086] Examples of the various compatible agents usable in the
present invention include, as described below, a liquid diene
polymer, a functional group containing polymer, an epoxy compound,
oxidized polyolefin wax, quinones, an organosilane compound and a
polyfunctional compound.
[0087] Liquid diene polymers suitable for the use in the present
invention include a homopolymer of conjugated diene and a copolymer
comprising conjugated diene and at least one monomer selected from
the group consisting of other conjugated dienes, vinyl monomers
(such as styrene and .alpha.-methylstyrene), olefins (such as
ethylene, propylene, butene-1, isobutylene, hexene-1, octene-1 and
dodecene-1) and mixtures thereof. The number-average molecular
weight of the polymers is 150 to 10,000, preferably 150 to 5,000.
The above homopolymers and copolymers can be prepared according to
the methods disclosed in U.S. Pat. Nos. 4,054,612, 3,876,721 and
3,428,699. These polymers include specifically polybutadiene,
polyisoprene, poly(1,3-pentadiene), poly(butadiene-isoprene),
poly(styrene-butadiene), polychloroprene,
poly(butadiene-.alpha.-methylstyrene),
poly(butadiene-styrene-isoprene), poly(butylene-butadiene), and the
like.
[0088] Functional group containing polymers suitable for the use in
the present invention include a copolymer of a vinyl compound,
which has in the molecule at least one functional group containing
at least one carbon-carbon double bond or carbon-carbon triple bond
and at least one of a carboxylic acid group, an acid anhydride
group, an amino group, a hydroxide group or a glycidyl group, and
an aromatic vinyl compound. The vinyl compound, which has in the
molecule at least one functional group containing at least one
carbon-carbon double bond or carbon-carbon triple bond and at least
one of a carboxylic acid group, an acid anhydride group, an amino
group, a hydroxide group or a glycidyl group, is the same as the
compounds usable as a modifier compound of polyphenylene ether. One
or more compounds selected from these compounds can be used as the
vinyl compound. Among these compounds, maleic anhydride, glycidyl
acrylate, and glycidyl methacrylate are preferred. Further, the
aromatic vinyl compound includes styrene, .alpha.-methylstyrene,
vinyl toluene and the like. One or more compounds selected from the
above compounds are used as the aromatic vinyl compound. Of these,
styrene is particularly preferred. Of the functional group
containing polymers, most preferred is a styrene-maleic anhydride
copolymer.
[0089] Epoxy resins suitable for the use in the present invention
include:
[0090] (1) an epoxy resin produced by condensing polyvalent phenol
(such as bisphenol A, tetrabromo bisphenol A, resorcinol, and
hydroquinone) and epichlorohydrin;
[0091] (2) an epoxy resin produced by condensing polyvalent alcohol
(such as ethylene glycol, propylene glycol, butylene glycol,
polyethylene glycol, polypropylene glycol, pentaerythritol, and
trimethylol ethane) and epichiorohydrin;
[0092] (3) a glycidyl etherified product of monovalent alcohols and
monovalent phenols such as phenyl glycidyl ether, butyl glycidyl
ether and cresyl glycidyl ether;
[0093] (4) a glycidyl derivative of an amino compound such as a
diglycidyl derivative of aniline; and
[0094] (5) an epoxidized product of a higher olefin, cycloalkene,
natural unsaturated oil (such as soybeans), or the above-mentioned
liquid diene polymers.
[0095] The oxidized polyolefin wax suitable for the use in the
present invention is well known, of which details and production
method are disclosed in U.S. Pat. Nos. 3,822,227 and 3,756,999 and
German Patent Nos. 3,047,915 and 2,201,862. In general, the wax is
prepared by oxidation or suspension oxidation of polyolefin.
[0096] The quinone compound suitable for the use in the present
invention is characterized in that it has in the molecule of
unsubstituted derivative at least one 6 membered carbon ring; at
least two carbonyl groups in the ring structure, both of which may
be in the same or, if more than one ring, different rings, provided
that they occupy positions corresponding to the 1,2- or
1,4-orientation of the monocyclic quinone; and at least two
carbon-carbon double bonds in the ring structure (wherein the
carbon-carbon double bonds and the carbonyl carbon-oxygen double
bond are in a ring structure and they are conjugated to each
other). When two or more rings are present in the non-substituted
quinone, they may be a condensed ring, a non-condensed ring or
both. Non-fused rings may be bonded to each other by a direct
carbon-carbon double bond or a hydrocarbon group having conjugated
unsaturation such as .dbd.C--C.dbd..
[0097] Further, substituted quinone is encompassed within the scope
of the present invention. If substitution is desired, a
substitution degree may be 1 to the maximum number of replaceable
hydrogen atoms. Examples of various substituents capable of being
present in the non-substituted quinone structure include halogen; a
hydrocarbon group such as chlorine, bromine and fluorine; a
branched or non-branched, saturated or unsaturated alkyl, aryl,
alkylaryl and cycloalkyl groups and halogenated derivatives
thereof; and a similar hydrocarbon group having a hetero atom,
particularly oxygen, sulfur and phosphorus (wherein these groups
bond to a quinone ring by an oxygen bond through a hetero
atom).
[0098] Examples of the various quinones include 1,2 -benzoquinone,
1,4-benzoquinone, 2,6-diphenylquinone, tetramethyldiquinone,
2,2'-diphenoquinone, 4,4'-diphenoquinone, 1,2-naphthoquinone,
1,4-naphthoquinone, 2,6-naphthoquinone, chloranils,
2-chloro-1,4-benzoquinone, 2,6-dimethylbenzoquinone, and the
like.
[0099] The organosilane compound suitable for the compatible agent
used in the present invention is characterized in that it contains
(a) at least one silicon atom bonded to a carbon through an oxygen
bond and (b) at least one functional group selected from the group
consisting of a carbon-carbon double bond or a carbon-carbon triple
bond and/or an amine group and a mercapto group (wherein the
functional group is not directly bonded to a silicon atom).
[0100] In the organosilane compound contains a C--O--Si component
usually exists as an alkoxyl or acetoxy group which is directly
bonded to a silicon atom. The alkoxyl or acetoxy group has less
than 15 carbon atoms in general, and may contain a hetero atom
(such as oxygen). Further, in the organosilane compound, two or
more silicon atoms may exist. When multiple silicon atoms exist,
they are bonded to each other through an oxygen bond (such as
siloxane), a silicon bond or a bifunctional organic group (such as
a methylene group or a phenylene group).
[0101] Examples of suitable organosilane compounds include
.gamma.-aminopropyl triethoxysilane, 2-(3-cyclohexanyl)ethyl
trimethoxysilane, 1,3-divinyl tetraethoxysilane, vinyl
tris-(2-methoxyethoxy)silane, 5-bicycloheptenyl triethoxysilane and
.gamma.-mercaptopropyl trimethoxysilane.
[0102] Polyfunctional compounds suitable for the compatible agent
of the present invention are of three types. The first type of
polyfunctional compounds are those having in the molecule both (a)
a carbon-carbon double bond or a carbon-carbon triple bond and (b)
at least one carboxylic acid, acid anhydride, acid halide,
anhydride, acid halide anhydride, acid amide, acid ester, imide,
amino or hydroxy group. Examples of such polyfunctional compounds
include maleic acid; maleic anhydride; fumaric acid; citraconic
acid; itaconic acid; maleimide; maleic hydrazide; reaction products
obtained from diamine and carboxylic acids such as maleic
anhydride, maleic acid, fumaric acid and the like; dichloro maleic
anhydride; maleic acid amide; unsaturated dicarboxylic acid (such
as acrylic acid, butenoic acid, methacrylic acid, t-ethylacrylic
acid, pentenoic acid, decenoic acid, undecenoic acid, dodecenoic
acid and linoleic acid); ester, acid amide or anhydride of the
unsaturated carboxylic acid; unsaturated alcohol (such as alkyl
alcohol, crotyl alcohol, methyl vinyl carbinol, 4-pentene-1-ol,
1,4-hexadiene-3-ol, 3-butene-1,4-diol,
2,5-diemthyl-3-hexane-2,5-diol, and alcohols represented by
C.sub.nH.sub.2n-5OH, C.sub.nH.sub.2n-7OH and C.sub.nH.sub.2n-9OH,
wherein n is a positive integer of 30 or less); unsaturated amine
obtained by substituting one or more --OH groups of the above
unsaturated alcohols with NH.sub.2 groups; and functionalized diene
polymer and copolymer. Of these, compatible agents suitable for the
composition of the present invention is maleic anhydride and
fumaric acid. This type of compatible agent can be reacted with
polyphenylene ether of the present invention in advance.
[0103] The second type of polyfunctional compound of the compatible
agent suitable for use in the present invention is a compound
having both (a) a group represented by the formula (OR) (wherein R
is hydrogen, an alkyl group, an aryl group, an acyl group or a
carbonyl dioxy group) and (b) at least two groups each of which may
be the same or different selected from the group consisting of
carboxylic acid, an acid halide, acid anhydride, anhydride, acid
halide anhydride, acid ester, acid amide, imide, amino and salts
thereof. Typical examples of this group of the compatible agent are
aliphatic polycarboxylic acid, acid ester, and acid amide which are
represented by the following formula
(R.sup.IO).sub.mR(COOR.sup.II).sub.n(CONR.sup.IIIR.sup.IV).sub.s
[0104] wherein R is a linear or branched chain, saturated aliphatic
hydrocarbon having 2 to 20 carbon atoms, preferably 2 to 10 carbon
atoms; R.sup.I is selected from the group consisting of hydrogen or
an alkyl, aryl, acyl or carbonyl dioxy group having 1 to 10 carbon
atoms, preferably 1 to 6 carbon atoms, most preferably 1 to 4
carbon atoms; R.sup.II is each independently selected from the
group consisting of hydrogen or an alkyl or aryl group having 1 to
20 carbon atoms, preferably 1 to 10 carbon atoms; R.sup.III and
R.sup.IV are each independently selected from the group consisting
essentially of hydrogen or an alkyl or aryl group having 1 to 10
carbon atoms, preferably 1 to 6 carbon atoms, most preferably 1 to
4 carbon atoms; m is equal to 1, (n+s) is 2 or more, preferably
equal to 2 or 3, and n and s are each 0 or more and wherein
(OR.sup.I) is .alpha. or .beta. relative to a carbonyl group, at
least two of which is separated by 2 to 6 carbon atoms. Obviously
R.sup.I, R.sup.II, R.sup.III and R.sup.IV cannot be an aryl group
when the respective substituent has less than 6 carbon atoms.
[0105] Examples of suitable polycarboxylic acid include citric
acid, malic acid and agaricic acid in addition to various
commercially available compounds such as anhydride and hydrated
acid. Of these, citric acid and malic acid are one of the preferred
compatible agents.
[0106] Examples of acid ester advantageous in the present invention
include N,N'-diethyl citric acid amide, N-phenyl citric acid amid,
N-dodecyl citric acid amide, N,N'-didodecyl citric acid amide, and
N-dodecyl malic acid.
[0107] The third type of polyfunctional compound of the compatible
agent suitable for use in the present invention is a compound
containing in the molecule both of (a) acid halide group, most
preferably acid chloride group and (b) at least one of a carboxylic
acid group, a carboxylic acid anhydride group, an acid ester group
and an acid amide group, preferably a carboxylic acid group and an
carboxylic acid anhydride group. Examples of the compatible agents
encompassed in this type include trimellitic anhydride acid
chloride, chloroformyl succinic anhydride, chloro fornyl succinic
acid, chloroformyl glutaric anhydride, chloroformyl glutaric acid,
chloroacetyl succinic anhydride, chloroacetyl succinic acid,
trimellitic acid chloride, and chloroacetyl glutaric acid.
[0108] Further, this type of compatible agents can be reacted in
advance with at least a part of polyphenylene ether to use as a
polyphenylene ether functionalized compound.
[0109] The above compatible agents are described in detail in U.S.
Pat. Nos. 4,315,086 and 4,642,358. They may be used alone or in
combination. Further, they may be directly added at the time of
melt mixing, or may be reacted in advance with one or both of
polyphenylene ether and polyamide or other resinous material used
for the production of the composition of the present invention.
[0110] An amount of the compatible agents is preferably 0.01 to 20
parts by weight, more preferably 0.1 to 10 parts by weight, based
on 100 parts by weight of the mixture of polyamide and
polyphenylene ether.
[0111] In the present invention, besides the above-listed
components, an additional component may be added in the range where
the effect of the components of the present invention are not
deteriorated.
[0112] Examples of such an additional component are listed
below.
[0113] There can be added other thermoplastic resins such as
polyester and polyolefin; an inorganic filler such as talc, kaolin,
zonotrite, wollastonite, titanium oxide, potassium titanate, carbon
fiber and glass fiber; flame retardant such as a halogenated resin,
silicone type flame retardant, magnesium hydroxide, aluminum
hydroxide, an organophosphate ester compound, polyphosphate
ammonium and red phosphorus; a fluorine polymer exhibiting effects
for prevention of dropping; plasticizer such as oil, low molecular
weight polyolefin, polyethylene glycol and aliphatic esters; and
auxiliary flame retardant such as antimony trioxide each in an
amount of less than 50 parts based on the total of 100 parts by
weight of components (A), (B) and (C).
[0114] Further, there can be added additives such as an
antioxidant, a ultraviolet absorbing agent, a light stabilizer,
zinc oxide, zinc sulfate and a nucleating agent for polyamide,
various peroxides, a slip agent, various dyes, pigment such as
titanium oxide, a release agent, and a known silane coupling agent
for improving affinity with the above-mentioned inorganic fillers
and resins each in an amount of less than 10 parts based on the
total of 100 parts by weight of components (A), (B) and (C).
[0115] These additional components can be used in combination.
[0116] Methods for producing the composition of the present
invention include a heat melt kneading method using a single-screw
extruder, a twin-screw extruder, a roll, a kneader, Brabender
Plastograph, a Banbery mixer and the like. Of these, a melt
kneading method using a twin-screw extruder is most preferred. A
melt kneading temperature is not particularly limited, but a
temperature where a preferable composition is obtained is
optionally selected in the range generally from 240.degree. to
360.degree. C.
[0117] A production method employed in the present invention is not
particularly limited, but there can be preferably exemplified
various methods such as (1) a method comprising adding components
(A), (B) and (C) at a time to melt knead; (2) a method comprising
melt kneading component (B) in advance and subsequently adding
components (A) and (C) to melt knead; (3) a method comprising melt
kneading components (A) and (B) and subsequently adding component
(C) to melt knead; (4) a method comprising melt kneading components
(B) and (C) in advance and subsequently adding component (A) to
melt knead; and (5) a method comprising melt kneading component (B)
and a part of component (A) and subsequently adding a residual part
of component (A) and component (C) to melt knead. As long as the
effects of the present invention is not deteriorated, any of the
methods can be employed.
[0118] The thus-obtained composition of the present invention is
molded into articles applied to various parts according to the
various known methods such as injection molding, extrusion molding
and hollow molding.
[0119] The composition of the present invention can be
advantageously used for exterior parts of motorcycles, interior
parts of automobiles, outer plates and exterior parts such as
fenders and door panels, and tray materials for integrated circuits
in the electric and electronic fields.
[0120] Hereinafter, the present invention is illustrated referring
to Examples.
PRODUCTION EXAMPLE 1
[0121] Production of PA66
[0122] Equimolar salt comprising adipic acid and hexamethylene
diamine (2.4 kg) and pure water (2.5 kg) were fed into a 10 liter
autoclave and fully stirred. After sufficiently substituted with
nitrogen, the mixture was heated from room temperature to
220.degree. C. over approximately one hour while stirring. At this
time, the internal pressure of the autoclave reached around 1.77
MPa in terms of gauge pressure due to natural pressure caused by
steam generated in the autoclave. Further, heating was continued
for two hours while discharging steam from the reaction system so
that the pressure would not be 1.77 MPa or more. Then, the stirring
was stopped and the internal pressure of the autoclave was reduced
to air pressure over approximately one hour by continuously
discharging steam from the reaction system. Stopping the heating
and shutting all the valves of the autoclave, the autoclave was
cooled down to room temperature. After cooling, the autoclave was
opened and approximately 2 kg of a polymer was taken out for
grinding.
[0123] The resultant polymer had viscosity relative to sulfuric
acid (.eta.r: polymer (1 g)/95.5% sulfuric acid (100 ml);
temperature 25.degree. C.) of 2.6, and concentrations of terminal
carboxyl groups and terminal amino groups of 75 milliequivalent/kg
and 45 milliequivalent/kg, respectively. The resultant polyamide
(hereinafter simply abbreviated as PA) was named PA66.
PRODUCTION EXAMPLE 2
[0124] Production of PA66/6I
[0125] A polymer was obtained according to the same procedure as in
Production Example 1 except that equimolar salt comprising adipic
acid and hexamethylene diamine (2.00 kg), equimolar salt comprising
isophthalic acid and hexamethylene diamine (0.50 kg), adipic acid
for adjusting a molecular weight (6.9 g) and pure water (2.5 kg)
were fed into the autoclave.
[0126] The resultant polymer had viscosity relative to sulfuric
acid (.eta.r: polymer (1 g)/95.5% sulfuric acid (100 ml);
temperature 25.degree. C.) of 2.2. The resultant PA was named
PA66/6I.
PRODUCTION EXAMPLE 3
[0127] Production of Modified PPE
[0128] 2,6-dimethyl phenol was subjected to oxidative
polymerization to obtain poly(2,6-dimethyl-1,4-phenylene ether)
(hereinafter simply abbreviated as PPE) having a reducing viscosity
of 0.52 (measured in 0.5 kg/dl chloroform solution at 30.degree.
C.). The resultant PPE (150 kg) and maleic anhydride (0.7 kg) as a
modifier were fed in FM500 type Henschel mixer (manufactured by
Mitsui Mining Co., Ltd.) applicable to jacket heating and nitrogen
substitution was conducted. An agitating blade was rotated at a
high speed to heat the content of the mixer to 200.degree. C. over
50 minutes with shear heat. After the jacket temperature reached
200.degree. C., the rotation at a high speed was continued for 5
minutes. Then, cool water was poured to the jacket for cooling it
down to obtain modified polyphenylene ether (hereinafter
abbreviated as MPPE) in a solid state.
[0129] The content (5 g) was dissolved into a chloroform solution
(100 ml). Acetone (300 ml) was added dropwise to the solution to
separate out polymer and the polymer was filtered out using a glass
filter. After this operation was repeated three times, the obtained
polymer was subjected to vacuum drying for 2 hours using a vacuum
dryer, of which the temperature was set at 140.degree. C.
[0130] Next, MPPE (1 g) was sandwiched between plates comprising
laminating a polytetrafluoroethylene sheet, an aluminum sheet and a
steel sheet from the inner side in the order listed, and was
compression molded at 100 kg/cm.sup.2 using a press molding
machine, of which temperature was set at 280.degree. C., to obtain
films.
[0131] Each of the resultant films was subjected to infrared
spectrophotometric analysis using a Fourier transform infrared
spectrophotometer, FT/IR-420 manufactured by JASCO Corp. By the
analysis on the MPPE film, a peak derived from maleic acid added to
polyphenylene ether was observed at 1790 cm.sup.-1.
[0132] An addition ratio of maleic anhydride, which was calculated
out from a calibration curve equation prepared in advance using a
mixture comprising PPE and maleic anhydride, was 0.34% by
weight.
PRODUCTION EXAMPLE 4
[0133] Production of Maleic Anhydride-modified Ethylene-butent-1
Copolymer Prepared Using a Single Site Catalyst
[0134] Maleic anhydride (1 part by weight) and a radical generator
(0.3 parts by weight), Parhexa 25B manufactured by NOF Corp., were
dry blended with an ethylene-butene-1 copolymer prepared using a
single site catalyst (100 parts by weight) [Mooney viscosity
ML.sub.1+4 (100.degree. C.) 16; MFR 3.6 g/10 min (190.degree. C.,
2.16 kg load)]. The resultant blend was fed to a co-rotating
twin-screw extruder (ZSK-25 manufactured by Werner & Pfleiderer
GmbH, Germany) and melt kneaded to obtain a modified
ethylene-butene-1 copolymer. When a film prepared from the
thus-obtained reactant was subjected to an analysis with an
infrared spectrophotometer after extraction of acetone, an addition
ratio of maleic anhydride was 0.9% by weight. The thus-obtained
ethylene-butene copolymer modified with maleic acid was named
MEBR-1.
PRODUCTION EXAMPLE 5
[0135] Production of Maleic Anhydride-modified Ethylene-butent-1
Copolymer Prepared Using a Ziegler Catalyst
[0136] A modified ethylene-butene-1 copolymer was obtained
according to the same procedure as in Production Example 4 except
that the ethylene-butene-1 copolymer was changed to an
ethylene-butene-1 copolymer prepared using a Ziegler catalyst
[Mooney viscosity ML.sub.1+4 (100.degree. C.) 16; MFR 3.6 g/10 min
(190.degree. C., 2.16 kg load)]. The resultant reactant had an
addition ratio of maleic anhydride of 0.85% by weight. The
resultant ethylene-butene copolymer modified with maleic acid was
named MEBR-2.
EXAMPLE 1
[0137] A co-rotating twin-screw extruder with upstream and
downstream supply ports (ZSK-40 manufactured by Werner &
Pfleiderer GmbH, Germany) was employed. A cylinder temperature of
the extruder was set in the range of 320.degree. to 280.degree. C.
From the upstream supply port, 37.8% by weight of PPE with a
reducing viscosity of 0.52 at 30.degree. C. in a chloroform
solution (0.5 g/dl) and 0.28% by weight of maleic anhydride as a
compatible agent were fed. From the downstream supply port, 56.7%
by weight of PA66 prepared in Production Example 1 and 5.2% by
weight of MEBR-1 prepared in Production Example 4 were fed. The fed
components were extruded at a screw revolution speed of 300 rpm,
cooled in a water bath and pelletized to obtain pellets.
[0138] In all of Examples, there were added 0.5 parts by weight of
zinc oxide, 0.5 parts by weight of zinc sulfate, 0.15 parts by
weight of copper iodide, 0.15 parts by weight of potassium iodide
and 0.02 parts by weight of sodium montanite based on 100 parts by
weight of the total of components (A), (B) and (C).
[0139] The resultant pellets were dried in vacuum at 100.degree. C.
for 5 hours, and molded into various test specimens using an
injection molding machine (IS-80EPN manufactured by Toshiba Machine
Co., Ltd.) of which cylinder temperature and mold temperature were
set at 290.degree. C. and 80.degree. C., respectively.
[0140] As an index of impact resistance, notched Izod impact
strength was measured according to ASTM-D256.
[0141] As an index of surface smoothness, average surface roughness
(Ra: .mu.m) was measured at a central part of a plate molded piece
having a length of 90 mm, a width of 50 mm and a thickness of 2 mm
using a contact surface roughness measuring apparatus.
[0142] Next, using a plate molded piece having a length of 100 mm,
a width of 100 mm and a thickness of 2 mm, a water absorption rate
and the dimensional changes after water absorption were
measured.
[0143] The plate molded piece was heat sealed in an aluminum coated
bag immediately after molding, and left in an atmosphere at
23.degree. C. for 48 hours. Then, its weight (W.sub.0), lengthwise
size (L.sub.0) and widthwise size (H.sub.0) were measured. Then,
after the plate molded piece was immersed in water at 23.degree. C.
for 21 days (3 weeks), weight (W.sub.21), lengthwise size
(L.sub.21) and widthwise size (H.sub.21) were measured.
[0144] Based on the obtained values, water absorption rate was
calculated using the following equation (3):
[(W.sub.21-W.sub.0)/W.sub.0].times.100 (3)
[0145] Further, the dimensional changes after water absorption were
calculated using the following equations (4) and (5):
Dimensional change (lengthwise):
[(L.sub.21-L.sub.0)/L.sub.0].times.100 (4)
Dimensional change (widthwise):
[(H.sub.21-H.sub.0)/H.sub.0].times.100 (5)
[0146] The measurement results are shown in Table 1 together with
the composition.
EXAMPLE 2
[0147] The same procedure as in Example 1 was conducted except
that:
[0148] from the upstream supply port, 34.5% by weight of PPE, 0.26%
by weight of maleic anhydride and 8.6% by weight of a hydrogenated
product of a styrene-butadiene-styrene triblock copolymer [bound
styrene content 30% by weight; number-average molecular weight
200,000: hereinafter abbreviated as SEBS] as a hydrogenated product
of the aromatic vinyl compound-conjugated diene compound copolymer
were fed; and
[0149] from the downstream supply port, 51.8% by weight of PA66 and
4.7% by weight of MEBR-1 were fed.
[0150] The measurement results are shown in Table 1 together with
the composition.
COMPARATIVE EXAMPLE 1
[0151] The same procedure as in Example 1 was conducted except that
MEBR-1 was changed to MEBR-2 prepared in Production Example 5. The
measurement results are shown in Table 2 together with the
composition.
EXAMPLE 3
[0152] The same procedure as in Example 1 was conducted except
that:
[0153] from the upstream supply port, 33.7% by weight of PPE, 0.25%
by weight of maleic anhydride and 8.4% by weight of SEBS were fed;
and
[0154] from the downstream supply port, 50.5% by weight of PA66,
4.6% by weight of MEBR-1 and 2.53% by weight of an
electroconductive carbon black (Ketjen Black EC-600JD manufactured
by Ketjen Black International Co., Ltd.; hereinafter abbreviated as
KB) were fed.
[0155] Then, impact resistance, surface smoothness, water
absorption rate and dimensional changes after water absorption were
measured.
[0156] Next, as an index for electroconductivity, resistivity
between end surfaces (width 6.4 mm; thickness 3.2 mm) of a molded
piece (length 128 mm; width 6.4 mm; thickness 3.2 mm) was measured.
Before the resistivity was measured, the end surfaces were coated
with a silver paste, dried with air, and further dried in an oven
at 80.degree. C. for 30 minutes. The resistivity was determined by
measuring resistivity at the time of applying 500 volts to the
molded piece using a resistivity measuring apparatus (DG-525
manufactured by Sanwa Electric Instrument Co., Ltd.).
[0157] Volume resistivity (.OMEGA..cm) was calculated by
multiplying the obtained resistivity by an area coated with a
silver paste and divided with the length of the molded piece. The
volume resistivity calculated in the above procedure was defined as
Volume Resistivity-A.
[0158] In order to measure an electroconductivity of a broken off
surfaces as described in prior art, a molded piece (length 128 mm;
width 6.4 mm; thickness 3.2 mm) was broken off at both ends to
prepare a test specimen (length 70 mm) with fractured surfaces at
both ends. The volume resistivity was calculated according to the
same procedure as for Volume Resistivity-A, i.e., by coating the
both fractured surfaces of the test specimen with a silver paste,
drying the surfaces, and measuring resistivity of the specimen. The
volume resistivity calculated in the above procedure was defined as
Volume Resistivity-B.
[0159] The measurement results are shown in Table 1 together with
the composition.
EXAMPLE 4
[0160] In the proportions shown in Table 1, there were incorporated
the following components:
[0161] PPE;
[0162] Citric acid as a compatible agent;
[0163] Hydrogenated product of a styrene-isoprene diblock copolymer
[bound styrene content 30% by weight, number-average molecular
weight 60,000: hereinafter abbreviated as SEP];
[0164] PA66;
[0165] Modified maleic anhydride [octene content 28% by weight; MFR
0.8 g/10 min (190.degree. C., 2.16 kg load), melting point
55.degree. C. (according to DSC method; heating speed 10.degree.
C./min), addition ratio of maleic anhydride 1.0% by weight:
hereinafter abbreviated as MEOR]; and
[0166] Ethylene-octene-1 copolymer prepared using a single site
catalyst [octene content 24% by weight, MFR 30 g/10 min
(190.degree. C., 2.16 kg load), melting point 60.degree. C.
(according to DSC method; heating speed 10.degree. C./min):
hereinafter abbreviated as EOR]. Then, the same procedure as in
Example 3 was conducted.
[0167] The measurement results are shown in Table 1 together with
the composition.
EXAMPLE 5
[0168] The same procedure as in Example 4 was conducted except that
PA66 and SEP were changed to Polyamide 6 [Ube Nylon 1013B
manufactured by Ube Industries, Ltd.: hereinafter abbreviated as
PA6] and SEBS, respectively, and the components were incorporated
in the proportion shown in Table 1. In this procedure, 25% by
weight out of the total of PA6 was fed from the upstream supply
port of the extruder and 75% by weight thereof was from the
downstream supply port.
[0169] The measurement results are shown in Table 1 together with
the composition.
EXAMPLE 6
[0170] The same procedure as in Example 5 was conducted except that
both PA66 and P6 were employed as a polyamide component and the
components were incorporated in the proportion as shown in Table 1.
A half amount of PA6 was fed from the upstream supply port of the
extruder and the other half was from the downstream supply
port.
[0171] The measurement results are shown in Table 1 together with
the composition.
EXAMPLE 7
[0172] The same procedure as in Example 3 was conducted except that
the polyamide component was changed to PA66/6I prepared in
Production Example 2. The measurement results are shown in Table 1
together with the composition. The resultant composition was
composed of a continuous phase of PA66/6I and dispersed phases
having a number-average dispersion diameter of 2 .mu.m.
EXAMPLE 8
[0173] The same procedure as in Example 7 was conducted except that
MEBR-1 was changed to a combination of MEOR and EOR and
incorporated in the proportion as shown in Table 1.
EXAMPLE 9
[0174] The same procedure as in Example 5 was conducted except that
citric acid was changed to maleic anhydride and incorporated in the
proportion as shown in Table 1. The measurement results are shown
in Table 1 together with the composition. The whole amount of PA6
was fed from the downstream supply port.
EXAMPLE 10
[0175] The same procedure as in Example 9 was conducted except that
a third of the whole amount of PPE was changed to MPPE prepared in
Production Example 3. The measurement results are shown in Table 1
together with the composition.
EXAMPLE 11
[0176] The same procedure as in Example 9 was conducted except that
the whole amount of PPE was changed to MPPE. The measurement
results are shown in Table 1 together with the composition.
COMPARATIVE EXAMPLE 2
[0177] The same procedure as in Example 3 was conducted except that
MEBR-1 was changed to SEBS. The measurement results are shown in
Table 2 together with the composition.
COMPARATIVE EXAMPLE 3
[0178] The same procedure as in Example 3 was conducted except that
MEBR-1 was changed to MEBR-2 prepared in Production Example 5. The
measurement results are shown in Table 2 together with the
composition.
COMPARATIVE EXAMPLE 4
[0179] The same procedure as in Example 5 was conducted except that
7.8% by weight of the total of MEOR and EOR was changed to a
hydrogenated product of a styrene-isoprene-styrene triblock
copolymer [bound styrene content 30% by weight, molecular weight
60,000: hereinafter abbreviated as SEPS]. The measurement results
are shown in Table 2 together with the composition.
COMPARATIVE EXAMPLE 5
[0180] The same procedure as in Example 5 was conducted except that
the whole of MEOR and EOR was changed to SEBS. The measurement
results are shown in Table 2 together with the composition.
COMPARATIVE EXAMPLE 6
[0181] The same procedure as in Example 6 was conducted except that
the whole of MEOR and EOR was changed to SEBS. The measurement
results are shown in Table 2 together with the composition.
[0182] The comparison of Example 1 is Comparative Example 1.
Compared with the composition obtained in Comparative Example 1,
that obtained in Example 1 exhibited excellent impact resistance
and surface smoothness and extremely small dimensional changes
though it had almost the same water absorption as that of
Comparative Example 1.
[0183] The composition obtained in Example 2 was such that prepared
by adding a hydrogenated product of an aromatic vinyl
compound-conjugated diene compound block copolymer to the
composition of Example 1. Compared with the composition of Example
1, that of Example 2 was improved in the balance of impact
resistance and surface smoothness.
[0184] Comparisons of Examples 3 to 6 are Comparative Examples 2 to
6. In Comparative Examples, the compositions were prepared using,
instead of an ethylene-.alpha.-olefin copolymer prepared with a
single catalyst, an ethylene-.alpha.-olefin copolymer prepared with
catalysts other than a single site one, a common styrene-butadiene
block copolymer, and a common styrene-isoprene copolymer. Compared
with such compositions obtained in Comparative Examples, those
obtained in Examples had excellent impact resistance, excellent
surface smoothness and extremely small dimensional changes though
they had almost the same water absorption as of the compositions of
Comparative Examples, and exhibited electroconductivity without
breaking off a molded piece.
Effect of the Invention
[0185] The composition of the present invention comprises
polyphenylene ether, polyamide and an ethylene-.alpha.-olefin
copolymer prepared using a single site catalyst, and exhibits
excellent impact resistance, excellent surface smoothness and small
dimensional changes after water absorption. Therefore, it can be
widely applied to the use such as automobile parts, electric and
electronic parts and mechanical parts.
1TABLE 1 Examples Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8
Ex. 9 Ex. 10 Ex. 11 Composition Fed from upstream supply port PPE
wt. % 37.8 34.5 33.7 35.0 34.9 35.1 33.7 25.3 29.9 20.0 MPPE wt. %
10.0 30.0 Maleic anhydride 0.28 0.26 0.25 0.25 0.20 0.20 wt. %
Citric acid wt. % 0.68 0.68 068 SEBS wt. % 8.6 8.4 6.9 6.9 8.4 6.1
7.0 7.0 7.0 SEP wt. % 6.8 PA6 wt. % 11.8 11.8 Fed from downstream
supply port PA66 wt. % 56.7 51.8 50.5 46.7 23.5 11.0 11.0 11.0
PA66/6I wt. % 50.5 51.6 PA6 wt. % 35.5 11.8 36.9 37.0 37.0 MEOR wt.
% 1.0 1.0 1.0 0.6 0.5 0.5 0.5 EOR wt. % 6.8 6.8 6.8 13.2 12.0 12.0
12.0 MEBR-1 wt. % 5.2 4.7 4.6 4.6 KB wt. % 2.53 3.00 2.44 2.44 2.53
3.04 2.59 2.60 2.60 Physical Property Izod impact strength 545 640
245 230 450 460 275 270 450 485 520 J/m Water absorption 4.0 4.2
4.1 3.9 3.9 3.8 3.4 3.5 3.8 3.8 3.8 wt. % Dimensional change 0.64
0.60 0.59 0.63 0.65 0.64 0.55 0.53 0.60 0.63 0.62 (lengthwise) %
Dimensional change 0.59 0.58 0.57 0.59 0.58 0.58 0.51 0.49 0.58
0.57 0.57 (widthwise) % Volume resistivity-A -- -- 4.5 .times.
10.sup.5 3.1 .times. 10.sup.4 5.6 .times. 10.sup.5 4.8 .times.
10.sup.5 1.0 .times. 10.sup.5 6.6 .times. 10.sup.4 1.2 .times.
10.sup.5 6.8 .times. 10.sup.4 1.9 .times. 10.sup.4 .OMEGA.
.multidot. cm Volume resistivity-B -- -- 6.9 .times. 10.sup.3 7.7
.times. 10.sup.2 8.2 .times. 10.sup.2 6.3 .times. 10.sup.2 2.9
.times. 10.sup.3 3.5 .times. 10.sup.2 4.0 .times. 10.sup.3 7.6
.times. 10.sup.2 2.7 .times. 10.sup.2 .OMEGA. .multidot. cm Surface
roughness 0.174 0.157 0.203 0.283 0.256 0.278 0.186 0.222 0.176
0.156 0.122 (Ra) .mu.m
[0186]
2TABLE 2 Comparative Examples Comp. Ex. 1 Comp. Ex. 2 Comp. Ex. 3
Comp. Ex. 4 Comp. Ex. 5 Comp. Ex. 6 Composition Fed from upstream
supply port PPE wt. % 37.8 33.7 33.7 35.0 34.9 35.1 Maleic
anhydride wt. % 0.28 0.25 0.25 Citric acid wt. % 0.68 0.68 0.68
SEBS wt. % 13.0 8.4 14.7 14.7 SEP wt. % 6.8 SEPS 7.8 PA6 wt. % 11.8
11.8 Fed from downstream supply port PA66 wt. % 56.7 50.5 50.5 46.7
23.5 PA6 wt. % 35.5 11.8 MEBR-2 wt. % 5.2 4.6 KB wt. % 2.53 2.53
3.00 2.44 2.44 Physical Property Izod impact strength J/m 490 110
195 155 175 140 Water absorption wt. % 4.2 4 4 3.8 3.9 3.9
Dimensional % 0.95 0.92 0.84 0.86 0.83 0.86 change (lengthwise)
Dimensional % 0.89 0.86 0.79 0.81 0.74 0.81 change (widthwise)
Volume resistivity-A .OMEGA. .multidot. cm -- .infin. .infin.
.infin. .infin. .infin. Volume resistivity-B .OMEGA. .multidot. cm
-- 5.5 .times. 10.sup.3 5.5 .times. 10.sup.4 2.8 .times. 10.sup.5
7.1 .times. 10.sup.5 5.4 .times. 10.sup.5 Surface roughness (Ra)
.mu.m 0.293 0.386 0.386 0.411 0.368 0.406
* * * * *