JPS59196355A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide a thermoplastic resin compsn. having well-balanced properties between heat and impact resistances, by mixing a specified graft copolymer with a modified multi-component copolymer obtd. from p-alkylstyrene, maleic anhydride, etc. CONSTITUTION:20-95wt% p-alkylstyrene of the formula, 5-45wt% maleic anhydride and 0-50wt% copolymerizable vinyl monomer are copolymerized. Ammonia or a prim. amine is reacted with the resulting multi-component copolymer to prepare a modified multi-component copolymer. Separately, 80-30pts.wt. vinyl monomer selected from among an arom. vinyl monomer, a vinyl cyanide monomer and (meth)acrylic acid monomer is graft-copolymerized in the presence of 20-70pts.wt. rubbery polymer to obtain a graft copolymer 5-50pts.wt. said graft copolymer is mixed with 95-50pts.wt. modified multi-component copolymer to obtain the titled resin compsn.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic resin composition that has well-balanced heat resistance and impact resistance.

Graft copolymers obtained by graft polymerizing vinyl monomers such as styrene, acrylonitrile, and methyl methacrylate in the presence of rubber-like polymers such as Geno-based rubbers are widely used as so-called ABS resins and MBS resins. Many studies have been conducted on improving the i-adic system and its quality. In improving the quality of copolymers shown in Graph 1, improving heat resistance is a particularly important issue, and a typical method is to replace part or all of the styrene of the vinyl monomer used with α- How to change to methylstyrene
No. 194). However, in this method, due to the difficulty of polymerization of α-methylstyrene, not only does copolymerization take an extremely long time, but the thermal decomposition temperature of the resulting copolymer is not high enough, resulting in poor thermal stability during high-temperature molding. It has the disadvantage of being lacking.

On the other hand, para-alkyl styrenes such as para-tertiary butylstyrene and para-methylstyrene have good polymerizability and have a higher heat distortion temperature than carbon styrene. - A heat-resistant resin composition using a copolymer of an alkyl styrene homopolymer has been proposed (U.S. Pat. No. 2,723,2
Publication No. 61 and AC5Polymer Prepri
nts Vol. 23, No. 2, p. 93, published September 1982).

However, although the heat distortion temperature of resins produced using these para-alkylstyrenes is higher than that of resin compositions mainly composed of styrene such as ABS resin, it is still insufficient. However, it cannot be said that it has satisfactory heat resistance.

Copolymers of α, β-unsaturated dicarboxylic acid anhydrides such as γ dimaleic anhydride and vinyl monomers such as aromatic vinyl monomers have high heat distortion temperatures. For example, Japanese Patent Publication No. 47-50775 discloses a composition of a copolymer of maleinoic anhydride and a vinyl monomer and a graft copolymer based on an olefin rubber. Proposed. However, maleic anhydride-based copolymers have the disadvantage of having a low thermal decomposition temperature and poor thermal stability during high-temperature molding.

Furthermore, copolymers of maleimide monomers such as N-methylmaleimide and N-ethylmaleimide and vinyl monomers such as aromatic vinyl monomers are
It is known to have high heat distortion temperature and thermal decomposition temperature (L, E.

Coleman et al J, Polymer
Sci. Volume 38, page 24'1, published in 1959), N-
A composition containing a copolymer composed of an aryl-substituted maleimide and a vinyl monomer and a graft copolymer based on an olefin rubber has been proposed (for example, JP-A-57-167341). However, in this composition, by increasing the N-aryl-substituted maleimide content, the heat resistance as represented by heat distortion temperature and thermal decomposition temperature is improved, but the impact resistance as represented by Izod impact strength is significantly decreased. Moreover, there is a drawback that N-aryl-substituted maleimide monomers are difficult to obtain at low cost.

In view of this situation, a method for inexpensively obtaining a resin composition with high heat deformation temperature, high thermal decomposition temperature, and excellent impact resistance was investigated.
Publication No. 5242 discloses a T-combined acid product by blending a modified copolymer obtained by imidizing a maleic anhydride copolymer with a primary amine and a graft copolymer based on an olefin rubber. has been proposed, but this composition has the advantage that it has greatly improved thermal stability compared to maleic anhydride-based compositions and can be obtained at a lower cost than resin compositions using maleimide-based monomers as starting materials. On the other hand, it still has the drawback of not having sufficient impact resistance, typified by Izotz impact strength.

Therefore, the present inventors aimed to obtain a low-cost resin composition that has a balance between heat resistance, represented by high heat distortion temperature and thermal decomposition temperature, and impact resistance, represented by impact strength. After extensive study, we found that a multi-component copolymer obtained by polymerizing a vinyl monomer mixture having a specific composition containing para-alkylstyrene and maleic anhydride as essential components was reacted with ammonia or a primary amine. A specific vinyl monomer (mixture) is added to the modified multi-component copolymer and rubber-like polymer obtained by
The present invention has been achieved by mixing in a specific ratio with a graft copolymer obtained by graft polymerization.

That is, the present invention provides 8) 20-95% by weight of para-alkylstyrene represented by the following general formula fl), 5-45% by weight of maleic anhydride, and other vinyl monomers copolymerizable with these monomers. Modified multi-component copolymer 5 obtained by reacting a multi-component copolymer obtained by polymerizing a monomer mixture consisting of O to 50% by weight with ammonia or a primary amine.
0 to 95 parts by weight and 1 component selected from aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylic acid monomers in the presence of 20 to 70 parts by weight of FB + rubbery polymer. At least one vinyl monomer 80-30
The present invention provides a thermoplastic resin composition containing 5 to 50 parts by weight of a graft copolymer obtained by polymerization of Kura 7I.

(In the formula, R, R2 and R3 represent hydrogen or a methyl group.) The modified multi-component copolymer formula of the present invention refers to 20 to 95% by weight of para-alkylstyrene, particularly 25 to 90% by weight. , 5-45% by weight, especially 10-40% by weight of maleic anhydride and 0-50% by weight, especially 0-45% by weight of other vinyl monomers copolymerizable with these monomers. The resulting multicomponent copolymer is obtained by reacting with ammonia or a primary amine.

Here, para-alkylstyreno, which is a copolymerization component of the multi-component copolymer, is a styrene derivative having an alkyl substituent at the para position represented by the above general formula (1), and specifically, p-methylstyrene, Mention may be made of p-ethylstyrene, p-isoprobylstyrene and p-t-methylstyrene, among others p-1-methylstyrene and p-t-
Putilus f. leno is preferably used. The para-alkylstyrene used for this purpose may contain isomers at the ortho position and/or the meta position within a range that does not impair the effects of the present invention, but usually the para-alkylstyrene is 80% by weight. %
As mentioned above, those containing preferably 90% by weight or more are used.

Other vinyl monomers used as copolymerization components of the multi-component copolymer are not particularly limited to vinyl monomers that can be copolymerized with para-alkyl styrene and maleic anhydride, and specifically include styrene. Representative aromatic vinyl monomers (excluding para-alkyl styrene), vinyl cyanide monomers such as acrylonitrile, and (meth)acrylic acid monomers such as methyl methacrylate. Examples include.

If the copolymerized amount of para-alkylstyrene in the multicomponent copolymer is less than 20% by weight or exceeds 95% by weight, the balance between heat distortion temperature and impact strength will be impaired, which is undesirable. In addition, the copolymerization amount of maleinoic anhydride is 5% by weight.
If it is less than 45% by weight, the heat distortion temperature will not be high enough, and if it exceeds 45% by weight, the impact strength will drop significantly, which is not preferable.

Furthermore, if the copolymerized amount of other vinyl monomers exceeds 50% by weight, the heat distortion temperature will drop significantly, which is not preferable.

Multi-component copolymers can be produced by conventional bulk polymerization, solution polymerization and bulk polymerization.
The polymerization can be carried out by suspension polymerization or the like, or the polymerization may be carried out in the presence of a rubbery polymer. Further, the entire monomer mixture of the multi-component copolymer may be charged into the polymerization tank at the beginning of polymerization, or some monomers may be charged in advance and the remaining amount may be charged continuously or intermittently afterwards. . In particular, it is desirable to charge maleic anhydride at a rate slower than the consumption rate of the other monomer mixtures.

The modified multi-component copolymer formula used in the present invention is obtained by reacting the multi-component copolymer obtained as described above with ammonia or a primary amine represented by the following formula (■).

(R in the formula is selected from hydrogen and substituted or unsubstituted hydrocarbons having 1 to 20 carbon atoms.) These compounds include ammonia, methylamine, isopropylamine, t-butylamine, Aniline, p-chloroaniline, p-toluidine, p-methoxyaniline,
Examples include 3.5-dimethylaniline, p-aminoethylbenzene, 4-aminodiphenyl, 2-aminodiphenylmethane, 1-aminonaphthalene, and 2-inoanotraceno, among which anilino is preferably used. These are used in a proportion of at least 2 equivalents to the maleic anhydride contained in the multi-component copolymer.

The modified multicomponent copolymer (5) is a multicomponent copolymer and the above formula in)
It is obtained by reacting with ammonia or a primary amine represented by It is obtained by reacting the polymer with ammonia or a primary amine, recovering the copolymer, and then imidizing it by heating cross-fertilization, especially by reacting it in an organic solvent at a temperature of 0 to 75°C, and removing it. A preferred method is to conduct a heated imide ring-closing reaction at a temperature of 150 to 350° C. after using a solvent.

The rubbery polymer which is a constituent component of the graft 2 copolymer of the present invention is a rubbery polymer with a glass transition temperature of -110°C or lower, such as polybutadiene rubber, acrylonitrile rubber, etc. Eno guys? 1 piece rubber (N, BR)
and styrene-butadiene co-electric composite rubber (SBR)
Geno-based rubbers such as, acrylic rubbers such as polybutyl acrylate and polypropyl acrylate, and ethylene-propylene-dieno-based rubbers (EPDM).

In the kraft copolymer (B), the ratio of the rubbery polymer to the vinyl monomer is important;
It is necessary to polymerize 80 to 30 parts by weight, especially 70 to 40 parts by weight of the vinyl monomer in the presence of 0 parts by weight, especially 30 to 60 parts by weight. If the proportion of the rubbery polymer is less than 20 parts by weight, the resulting resin composition will not have sufficient impact resistance, and if it exceeds 70 parts by weight, the mechanical strength of the resulting composition will decrease. I like it.

The aromatic vinyl monomer which is a copolymerization component of the graft copolymer (B) includes styrene, α-methylstyrene, p
-methylstyrene, p, -t-butylstyrene and p
-Chlorstyrene, among others, styrene,
α-methylstyrene and pt-butylstyrene are preferably used. Examples of vinyl cyanide monomers include acrylonitrile, tsukuacrylonitrile, and α-chloroacrylonitrile, with acrylonitrile being preferred. Examples of the (meth)acrylic acid monomer include methyl acrylate, methyl methacrylate, butyl tuccrylate, and among them, methyl tuccrylate is preferably used.

Incidentally, the graft copolymer tB) is produced by a known polymerization method such as emulsion polymerization, bulk polymerization, bulk temperature-sensitive polymerization, or the like.

The resin composition of the present invention is obtained by blending a kraft copolymer (Bl) into a modified multi-component copolymer, and the blending ratio of (5) is 50 to 95 parts by mass, particularly 55 to 95 parts by weight.
90 parts by weight, (B) 5 to 50 parts by weight, especially 10 to 4 parts by weight
5 parts by weight (100 parts by weight in total). If the amount added to the modified multi-component copolymer is less than 50 parts by weight, only a composition with an extremely low heat distortion temperature will be obtained;
If the amount exceeds 1 part by weight, the impact resistance of the composition decreases, which is not preferable. If the amount of the graft copolymer tB) is less than 5 parts by weight, the impact resistance of the composition will be insufficient, and if it exceeds 50 parts by weight, the heat distortion temperature will drop significantly, which is not preferred.

There is no particular restriction on the method of blending the graft copolymer (B) into the modified multi-component copolymer, for example, the powdery polymers may be mixed in advance or not mixed before being fed to the extruder at a desired ratio;
A method such as melt mixing is adopted.

Note that various properties can be exerted by blending other polymers with the thermoplastic resin composition of the present invention. Such polymers include styrene-acrylonitrile copolymer, a-methylstyrene-acrylonide 1
) vinyl-based (co)polymers such as styrene-〇-methylstyrene-acrylonitrile copolymer and α-methylstyrene-notyl methacrylate acrylonitrile copolymer, and polyamide-based polymers typified by nylon. , polyester polymers typified by polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polyacetal.

In addition, antioxidants such as ordinary hindered phenol antioxidants, rhino antioxidants, and sulfur antioxidants are added to the thermoplastic resin composition of the present invention to improve thermal stability, and lubricant It is also possible to further improve fluidity by adding . Further, depending on the purpose, fiber reinforcing agents such as glass fibers and carbon fibers, inorganic fillers, colorants, pigments, conductive materials, etc. can be added. Further, flame retardation can be achieved by mixing general halogenated organic compound flame retardants such as tetrabromohisphenol A, thecabromohyphenyl ether, and brominated polycarbonate together with anotymone oxide in the resin composition of the present invention.

As explained above, the thermoplastic resin composition of the present invention has unbalanced heat resistance, represented by heat distortion temperature and thermal decomposition temperature, and impact resistance, represented by impact strength. It is expected that this material will be utilized in a variety of applications.

The present invention will be further explained below with reference to Reference Examples and Examples. The heat distortion temperature in the reference examples and examples is AST.
MD648-56. Izotsu impact strength is ASTM
Measured according to D256-56Method A. The thermal decomposition temperature was determined by increasing the temperature at a rate of 10° C./min under a nitrogen stream using a thermogravimetric analyzer, measuring the weight change of the sample, and determining the temperature at which the sample weight decreased by 3% by weight as the thermal decomposition temperature. In addition, the number of parts represents parts by weight, and % represents weight N%.

Reference Example 1 [Preparation of modified multicomponent copolymer (A-1)] Autoclave E equipped with a stirrer and addition device 80 parts of p-methylstyrene, 40 parts of methyl ethyl ketone and 0.1 part of t-butyl peroxybenzoate (initiator)
5 parts were charged and sufficiently dissolved. Separately, a maleinoic anhydride-methyl ethyl ketone solution was prepared by dissolving 20 parts of maleic anhydride in 40 parts of methyl ethyl ketone.

Next, the temperature inside the polymerization tank was maintained at 115 DEG C., and while stirring, a maleic anhydride-methyl ethyl ketone solution was supplied at a rate of 12 parts/hr for 5 hours.

After the supply was completed, stirring was continued for 2 hours, and the polymerization was stopped by cooling. The polymerization rate was determined to be 99% using gas chromatography. 19 parts of anilino was added to the obtained colorless, transparent and viscous reaction liquid, and the mixture was stirred at 50°C for 1 hour to react.

Thereafter, the polymerization tank was cooled, and the pale yellow reaction liquid was added to toluene to remove residual monomers and methyl ethyl ketone, and dried to obtain a modified multi-component copolymer (A-1).

Reference Example 2 [Preparation of modified multicomponent copolymer (A-2)] In the same polymerization tank as in Reference Example 1, 50 parts of p-, t-butylstyrene, 10 parts of acrylonitrile, 20 parts of a-methylstyrene, and methyl 20 parts of ethyl ketone and 0.15 parts of t-butyl peroxybenzoate (initiator) were charged and sufficiently dissolved.

Separately, add 20 parts of maleic anhydride to 4 parts of methyl ethyl ketone.
A maleic anhydride-methyl ethyl ketone solution was added at a rate of 12 parts/hr for 5 hours. After the supply was completed, stirring was continued for 2 hours, and then the mixture was cooled to stop the polymerization. The polymerization rate was determined to be 98% using gas chromatography. 19 parts of aniline was added to the resulting colorless, transparent and viscous reaction solution, and the mixture was stirred at 50° C. for 1 hour to react. Thereafter, the polymerization tank was cooled, and the resulting pale yellow reaction liquid was added to toluene to remove residual monomers and methyl ethyl ketone, and dried to obtain a modified multi-component copolymer (A
-2) was obtained.

Reference Example 3 [Preparation of modified multi-component copolymer (A-3)] Polymerization was carried out in the same manner as in Reference Example 1, except that styrene was used instead of p-methylstyrene in Reference Example 1, and a modified multi-component copolymer was prepared. (A, :3) was obtained.

Reference example 4 [Preparation of multicomponent copolymer (A'-1)] Reference example 1
80 parts of p-methylstyrene, 20 parts of methyl ethyl ketone and 0.5 parts of t-butyl peroxybenzoate (initiator) were charged into a polymerization tank similar to the above and sufficiently dissolved. - Bansho (20 parts of maleic anhydride is mixed with 40 parts of methyl ethyl ketone)
A solution of maleic anhydride and methyl ethyl ketone dissolved in 1 part was supplied at a rate of 12 parts/hr for 5 hours. After the supply was completed, stirring was continued for 2 hours, and the polymerization was stopped by cooling. The polymerization rate was determined using Cass chromatography and was found to be 99.
%Met. The resulting colorless, transparent and viscous reaction liquid was added to petroleum benzene to remove residual monomers and notyl ethyl chloride, and dried to obtain a multi-component copolymer (A'-1). Ta.

Reference example 5 [Preparation of multicomponent copolymer (A'-2)] Reference example 1
76 parts of p-71butylstyreno, 24 m of acrylonitrile, 0.4 part of azohisisobutyronitrile (initiator) and 0.3 part of t-dotesylmercaptan (chain transfer agent) were charged into a polymerization tank similar to E. Partially kenated polyhinyl alcohol (GM-14' manufactured by Nippon Gosei Kagaku Co., Ltd.)
An aqueous solution prepared by dissolving 0.2 part of Hydroquine Provia Methylcellulose (90 SH-400, manufactured by Shin-Etsu Chemical Co., Ltd.) in 200 parts of deionized water was added and stirred vigorously.

Next, suspension polymerization was carried out while maintaining the temperature inside the polymerization tank at 70° C. and stirring vigorously for 4 hours. The polymerization rate was determined to be 95% using Gas Chroma 1-Graphie. The obtained polymerization slurry was filtered, washed with water, and then dried to obtain a multi-component copolymer (A'-2').

Reference example 6 [Preparation of multicomponent copolymer (A'-3)] Reference example 1
In a polymerization tank similar to the above, 770 parts of pt-butyl styrene, 20 parts of methyl ethyl ketone, and 0 petzyl peroxide (initiator) were added.
．． 1 part and t-dotesyl mercaptan (chain transfer agent)
01 part was charged and sufficiently dissolved. - 30 parts of N-phenylmaleimide and 7150 parts of methyl ethyl keto (dissolved N-phenylmaleimide-methyl ethyl keto)
A solution was prepared.

Next, while maintaining the temperature inside the polymerization tank at 75°C and stirring, add 40% of the N-phenylmaleimide-methyl ethyl ketone solution.
It was fed at a rate of 5 parts/hr for 4 hours. After the dropwise addition was completed, stirring was continued for 2 hours, and the polymerization was stopped by cooling. The polymerization rate was determined to be 98% using gas chromatography.

The obtained pale brown, transparent and viscous reaction liquid was dropped into methanol to remove residual monomers and methyl ethyl ketone and dried to obtain a multi-component copolymer (A'-3).

Reference 8 Example 7 [Preparation of graft copolymer (B-1)] Polybutadieno rubber latex 60 was placed in the same polymerization tank as in Reference Example 1.
part (solid content equivalent), trisodium phosphate 1.0 part, potassium persulfate (initiator) 0.5 part, potassium oleinoate 3 parts
．． 0 parts and 100 parts of deionized water were charged and dissolved.

- 30 parts of methylef, 10 parts of acrylonitrile and 0.1 part of t-dotesylmercaptan were charged into the dropping funnel. After the temperature inside the polymerization tank was set to 65°C, the above monomer mixture was added dropwise to the polymerization tank (ζ) over a period of 3 hours. After the addition was completed, stirring was continued for 2 hours, and then the mixture was cooled to complete the polymerization.

The polymerization rate was determined by gas chromatography and was 96%.
Met.

The obtained latex was coagulated using magnesium sulfate, washed with water, and dried to obtain a graft copolymer (B-1).
I got it.

Reference Example 8 [Preparation of graft copolymer (B-z)] In the same polymerization tank as in Reference Example 1, ethylene/propylene dieno rubber (iodine i value 24.mu, 4-viscosity 65.ethylene/furopylene-77 , 67224 molar ratio) was dissolved in a mixed solvent of 150 parts of n-heptano and 250 parts of isoprobilbencef, then 35 parts of methylene ref, 10 parts of acrylonitrile and benozoyl peroxide (υa initiator)
Add 1 part and mix evenly.

Next (add 700 parts of deionized water to polyacrylic acid (degree of polymerization: 2)
000) After adding an aqueous solution containing 3 parts of a 25% aqueous solution, the gas phase was replaced with nitrogen gas and heated to 80°C with vigorous stirring.
Graft polymerization was carried out for 7 hours. The polymerization rate was 98% as determined by gas chromatography.

The obtained polymer slurry was filtered, washed with a large amount of methanol, and then dried to obtain a graft copolymer (B-2).

Examples Modified multi-component copolymers prepared in Reference Examples 1 to 3 (A-1 to 3
), the multicomponent copolymers prepared in Reference Examples 4 to 6 (A'-1 to
3) and the graft copolymers (B-1, 2) prepared in Reference Examples 7 and 8 were melt-extruded using an extruder according to the blending ratio shown in Table 1 (L/f), and then injection molded. The physical properties of the test pieces were measured. The measurement results of heat distortion temperature, thermal decomposition temperature and Izod impact strength are shown in Table 11 along with the blending ratio.

Table-1 As is clear from Table-1, the resin composition of the present invention
Items 4) to 4) have high thermal deformation temperatures, high thermal decomposition temperatures, and high Izod impact strengths, and have an excellent balance between heat resistance and impact resistance. On the other hand, when the blending ratio of the present invention is exceeded (1
'! 15), maleic anhydride-based multicomponent copolymer (A'-1
) is used as it is without denaturation (Nci6), p-
When a modified multi-component copolymer (A-3') obtained by imidizing a multi-component copolymer that does not contain alkylstyrene is used (Nct7), a multi-component copolymer that does not contain maleinoic anhydride (A'- (18) and a multicomponent copolymer obtained by copolymerizing maleimide monomers (18).
When A'-3) is used (Nα9), only a composition having a low heat distortion temperature, thermal decomposition temperature, or Izod impact strength can be obtained.

Patent applicant Higashi Shikikai Co., Ltd.

Claims (1)

[Claims] 20 to 95% by weight of para-alkylstyrene represented by the following general formula +1), 5 to 45% by weight of maleinoic anhydride, and other vinyl monomers copolymerizable with these monomers. 50 to 95 parts by weight of a modified multicomponent copolymer obtained by reacting a multicomponent copolymer obtained by polymerizing a monomer mixture consisting of 0 to 50% by weight with ammonia or a primary amine, and (B) rubber. At least one type of vinyl monomer selected from aromatic vinyl monomers, vinyl cyanide monomers, and (meth)acrylic acid monomers is added in the presence of 20 to 70 parts by weight of the polymer. 1. A thermoplastic resin composition containing 5 to 50 parts by weight of a graft copolymer obtained by graft polymerizing 80 to 30 parts by weight. (However, R1, R2 and R3 in the formula represent hydrogen or a methyl group.)