JP2945404B2 - Resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a resin composition, and more specifically, a styrene resin composition useful for heat-resistant parts and industrial heat-resistant structural materials in automobiles, home appliances, electric and electronic devices, and the like. About.

[Problems to be solved by conventional technology and invention]

In recent years, styrene-based polymers with high syndiotacticity have better mechanical strength, heat resistance, solvent resistance, and electrical properties than styrene-based polymers with atactic structure. For the purpose of improving the properties and solvent resistance, various studies have been made on the incorporation of a styrenic polymer having a syndiotactic structure. For example, Japanese Patent Application Laid-Open No. 62-257950 discloses that a polystyrene having a syndiotactic structure is blended for the purpose of improving the heat resistance of a thermoplastic resin. According to this formulation, although the heat resistance of the thermoplastic resin is certainly improved, the tensile strength, elongation, and the like are significantly reduced in a composition with a resin having poor affinity for polystyrene. In some cases, such a decrease in mechanical properties is not preferable. Furthermore, not only these mechanical properties deteriorate, but also there are problems in appearance such as peeling of the surface layer of the molded product.

To solve these problems, in the specification of Japanese Patent Application No. 63-3844, the research group of the present inventors has developed a styrenic polymer having a syndiotactic structure and a thermoplastic resin having poor affinity. In blending, a technique was proposed in which a specific block copolymer was added as an affinity and dispersibility improver. For example, a technique of adding a block copolymer of polystyrene-polyamide when blending with polyamide, and a technique of adding a block copolymer of polystyrene-polybutylene terephthalate when blending with polybutylene terephthalate. That is, in this technique, a block copolymer of a partner resin which is substantially blended with polystyrene is added as a modifier, and to a certain extent, compared to the technique described in JP-A-62-257950. Reforming effect is achieved,
In particular, the mechanical properties are greatly improved.

However, in this technique, in preparing a blend, it is necessary to prepare a block copolymer in advance,
Industrial production requires complicated processes, which may be a disadvantage.

Therefore, the present inventors, when blending a styrene-based polymer having a syndiotactic structure and a thermoplastic resin having poor affinity, a modifier that can be industrially mass-produced, or mass-produced. Intensive research was conducted to improve the affinity and dispersibility of the thermoplastic resin by adding a specific modifier.

[Means for solving the problem]

As a result, they have found that a styrene-based copolymer obtained by copolymerizing a vinyl compound having an epoxy group or an α, β-unsaturated carboxylic anhydride is a modifier that achieves the above object. The present invention has been completed based on such findings.

That is, the present invention provides (a) 5-95% by weight of a styrene polymer having a syndiotactic structure and (b)
Thermoplastic resin having at least one polar group selected from a carboxyl group, a hydroxyl group and an amino group;
(C) with respect to 100 parts by weight of a polymer mixture consisting of
A styrene-based copolymer obtained by copolymerizing a vinyl compound having an epoxy group in an amount of 0.01 to 30 mol% or a styrene-based copolymer obtained by copolymerizing an α, β-unsaturated carboxylic anhydride in an amount of 0.01 to 5 mol%; It is intended to provide a resin composition in which parts by weight are blended.

As described above, the resin composition of the present invention comprises the component (a),
Component (b) and component (c) are the main components.
Here, the component (a) is mainly a styrene polymer having a syndiotactic structure, and the term “syndiotactic structure” of the styrene polymer mainly means that the stereochemical structure is mainly a syndiotactic structure; It has a steric structure in which phenyl groups and substituted phenyl groups, which are side chains, are alternately located in opposite directions to the main chain formed from carbon bonds, and its tacticity is determined by nuclear magnetic resonance using isotope carbon ( ¹³ C-NMR method). Tacticity measured by ¹³ C-NMR method is
The abundance ratio of a plurality of continuous structural units, for example, a diad for two, a triad for three, and a pentad for five can be indicated by a syndiotactic structure referred to in the present invention. Styrene polymer is usually 75% or more, preferably 85% by dyad.
Above or 30% for pentad (racemic pentad)
Polystyrene, poly (alkylstyrene), poly (halogenated styrene), poly (alkoxystyrene), poly (vinylbenzoic acid ester) having a syndiotacticity of 50% or more, and a mixture thereof, The copolymer as the main component is referred to. Here, poly (alkylstyrene) includes poly (methylstyrene), poly (ethylstyrene), poly (isopropylstyrene), poly (tert-butylstyrene) and the like. Examples include poly (chlorostyrene), poly (bromostyrene), and poly (fluorostyrene). Examples of poly (alkoxystyrene) include poly (methoxystyrene) and poly (ethoxystyrene). Of these, particularly preferred styrene polymers include polystyrene, poly (p-methylstyrene), poly (m-methylstyrene), poly (p-tert-butylstyrene), poly (p-chlorostyrene), and poly (p-chlorostyrene). m-chlorostyrene), poly (p-fluorostyrene), and a copolymer of styrene and p-methylstyrene.

The styrene polymer as the component (a) used in the present invention is not limited in molecular weight, but preferably has a weight average molecular weight of 10,000 or more, and more preferably 50,000 or more.
The above are optimal. Further, the molecular weight distribution is not limited in its width, and various molecular weight distributions can be applied. Such a styrene-based polymer having a predominantly syndiotactic structure is, for example, a styrene-based polymer in an inert hydrocarbon solvent or in the absence of a solvent, using a titanium compound and a condensation product of water and a trialkylaluminum as a catalyst. It can be produced by polymerizing a monomer (a monomer corresponding to the above-mentioned styrene-based polymer) (JP-A-62-187708).

On the other hand, the component (b) of the present invention is a thermoplastic resin having at least one polar group selected from a carboxyl group, a hydroxyl group and an amino group at the terminal, as described above. Examples of such a thermoplastic resin include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polycyclohexane dimethylene terephthalate, polyoxyethoxybenzoate, polyethylene naphthalate, and the above-mentioned polyester component and other acid components and / or glycol. Ingredients such as acid components such as isophthalic acid, p-oxybenzoic acid, adipic acid, sebacic acid, glitalic acid, diphenylmethanedicarboxylic acid, dimer acid, hexamethylene glycol,
Polyester copolymerized with glycol components such as diethylene glycol, neopentyl glycol, bisphenol A, neopentyl glycol alkylene oxide adduct, aromatic polyester-polyether block copolymer, aromatic polyester-polylactone block copolymer, poly Broadly defined polyester such as arylate, nylon 6, nylon 6.6, nylon 6.9, nylon 5.9, nylon 6.12, nylon 6/6, 6, polyxylylene adipamide, polyhexamethylene terephthalamide And polyamides such as polyphenylene phthalamide, polyxylylene adipamide / hexamethylene adipamide, polyester amide elastomer, polyether amide elastomer, polyether ester amide elastomer, and dimer acid copolymer amide. Among these, particularly preferred polyesters are polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and polyarylates are known as U-polymers comprising bisphenol A and terephthalic acid as constituents. The polyamide is nylon 6, nylon 6.6.

The composition of the present invention further comprises, as component (c), a styrene-based copolymer obtained by copolymerizing a vinyl compound having an epoxy group in an amount of 0.01 to 30 mol% or an α, β-unsaturated carboxylic anhydride in an amount of 0.01 to 5 mol%. It contains a styrene copolymer copolymerized by mol%. As these styrene-based copolymers, those having a weight average molecular weight of 10,000 to 800,000, preferably 50,000 to 5
Use 00,000. This weight average molecular weight is 10,000
If less, the effect of improving the dispersibility is small, and conversely,
Decreases mechanical properties. In addition, the weight average molecular weight is 800,00
If it exceeds 0, the viscosity of the composition may be increased, the moldability may be reduced, or an independent phase may be formed in the composition, and the effect of modifying the affinity and dispersibility may be substantially lost.

0.01 to 30 mol% of a vinyl compound containing an epoxy group
In producing the copolymerized styrene-based copolymer, examples of the vinyl compound containing an epoxy group to be copolymerized with the styrene-based compound include glycidyl methacrylate, glycidyl acrylate, vinyl glycidyl ether, allyl glycidyl ether, and hydroxyalkyl (meth) acrylate. And glycidyl ethers such as polyalkylene glycol (meth) acrylate, and epoxy group-containing copolymerizable unsaturated monomers such as glycidyl itaconate. A styrene polymer obtained by copolymerizing such an epoxy group-containing copolymerizable unsaturated monomer can be produced by ordinary bulk polymerization, solution polymerization, suspension polymerization or emulsion polymerization utilizing radical polymerization.

The vinyl compound containing an epoxy group has a copolymer composition in the styrene-based polymer of 0.01 to 30 mol%, preferably
The copolymerization is carried out at a ratio of 0.1 to 20 mol%. If the copolymer composition of the vinyl compound containing an epoxy group is less than 0.01 mol%, the effect of improving dispersibility is small, and phase separation may occur. If it exceeds 30 mol%, an independent phase is formed. Substantially loses the effect of modifying affinity and dispersibility. Also, gelation occurs, which is considered to be the result of the reaction of the epoxy group.

The epoxy group-containing vinyl compound as described above is 0.01 to 30.
Of the styrene copolymers copolymerized by mol%, a copolymer of glycidyl methacrylate and styrene is particularly preferred. What is necessary is just to apply what is marketed as a Blenmer CP series from Nippon Oil & Fats Co., Ltd. for this copolymer, for example.

The composition of the present invention may contain, as the component (c), a styrene copolymer obtained by copolymerizing 0.01 to 5 mol% of an α, β-unsaturated carboxylic anhydride. Here, the α, β-unsaturated carboxylic anhydride may be any monomer that can be copolymerized with the styrene-based compound, such as maleic anhydride, chloromaleic anhydride, citraconic anhydride, butenylsuccinic anhydride,
And tetrahydrophthalic anhydride. Styrene polymers obtained by copolymerizing these unsaturated carboxylic anhydrides can be produced by ordinary bulk polymerization, solution polymerization, suspension polymerization or emulsion polymerization utilizing radical polymerization.

The α, β-unsaturated carboxylic anhydride is copolymerized in the styrene-based copolymer at a ratio such that the copolymer composition is 0.01 to 5 mol%, preferably 0.1 to 3 mol%. α, β-unsaturated carboxylic acid anhydride copolymer composition is 0.
If it is less than 01 mol%, the effect of improving dispersibility is small, and phase separation may occur.
An independent phase is formed and the effect of modifying affinity and dispersibility is substantially lost.

Α, β-unsaturated carboxylic anhydride as described above
Of the styrene-based copolymers copolymerized at モ ル 5 mol%, a copolymer of maleic anhydride and styrene is particularly preferred. Such a copolymer is available, for example, from Idemitsu Petrochemical Co., Ltd.
What is marketed as a More Max series may be used.

In the resin composition of the present invention, the above-mentioned styrene polymer having a syndiotactic structure as the component (a) may be used in an amount of 5 to 5.
95% by weight, preferably 10 to 90% by weight, 95 to 5% by weight, preferably 90 to 10% by weight of the thermoplastic resin as the component (b)
In a proportion of Here, the mixing ratio of the thermoplastic resin is 95
If the amount is more than 5% by weight, the heat resistance, rigidity and chemical resistance of the obtained composition will be reduced, and if it is less than 5% by weight, the mechanical properties will be reduced.

The resin composition of the present invention is based on 100 parts by weight of the mixture containing the components (a) and (b) in the above proportions.
Component (c) is 0.01 to 15 parts by weight, preferably 0.1 to 10 parts by weight. When the amount of the component (c) is less than 0.01 part by weight, the effect of improving dispersibility is small, and phase separation may occur. On the other hand, if it exceeds 15 parts by weight, it is unnecessarily excessive, causing problems such as gelation and impairing heat resistance.

The resin composition of the present invention basically has the above (a) to
(C) Component, but various additives such as various rubbery polymers and / or inorganic fillers or other antioxidants, nucleating agents, lubricants, etc., unless the object of the present invention is further impaired. Can be blended as needed. Here, as the rubber-like polymer, various ones can be used, but the most preferable one is a rubber-like copolymer containing a styrene-based compound as one component, for example, a styrene-butadiene block copolymer. Rubber, rubber obtained by partially or completely hydrogenating the butadiene portion of a styrene-butadiene block copolymer, styrene-butadiene copolymer rubber, methyl acrylate-butadiene-styrene copolymer rubber, acrylonitrile-butadiene-styrene copolymer And a styrene-based polymer having a syndiotactic structure, which is a component (a) mainly, because each of them has a styrene unit. Good dispersibility for coalescence, resulting in significant improvement in physical properties

Further, examples of the rubbery polymer include natural rubber, polybutadiene, polyisoprene, polyisobutylene, neoprene, ethylene-propylene copolymer rubber, polysulfide rubber, thiochol rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, and the like. Can be

Further, the following polymers can also be used as the rubbery polymer. That is, first, there is a resin polymer obtained by polymerizing one or more vinyl monomers in the presence of a rubbery polymer mainly composed of alkyl acrylate and / or alkyl methacrylate (alkyl acrylates). . Here, the rubbery polymer mainly composed of alkyl acrylates refers to other vinyl monomers copolymerizable with 70% by weight or more of the alkyl acrylates, such as methyl methacrylate, acrylonitrile, vinyl acetate, and styrene. And 30% by weight or less. In this case, a polymer obtained by appropriately adding and reacting a polyfunctional monomer such as divinylbenzene, ethylene dimethacrylate, triallyl cyanurate or triallyl isocyanurate as a crosslinking agent is also included. Specific examples of the rubbery polymer belonging to the above include a MAS elastic body (a rubber latex obtained by copolymerizing methyl methacrylate and butyl acrylate, and styrene added thereto and graft-polymerized (commercially available as ROHM & EXL-2330 (trade name, manufactured by Haas Co., Ltd.) or M-101 (trade name, manufactured by Kaneka Chemical Co., Ltd.)).

In addition, a copolymer obtained by copolymerizing an alkyl acrylate and / or an alkyl methacrylate with a polyfunctional polymerizable monomer having a conjugated diene double bond is added to one or two types of vinyl monomers. There is a resin polymer obtained by polymerizing the above. When obtaining this copolymer, a vinyl monomer and a cross-linking agent can be added in the same manner as described above. As a specific example of the rubbery polymer belonging to the above, octyl acrylate and butadiene are used in a ratio of former: latter = 7: 3, and styrene and methyl methacrylate are added to a rubber latex obtained by copolymerization, followed by grafting. MABS elastic materials such as graft copolymers obtained by polymerization, or rubber latex obtained by copolymerizing methyl methacrylate and butadiene,
An MBS elastic body such as a graft copolymer obtained by adding styrene and performing graft polymerization (a commercially available product manufactured by Mitsubishi Rayon Co., Ltd., trade name: Metablen C-223) can be exemplified.

Further, as another elastic body, an AABS elastic body (a rubber latex obtained by copolymerizing butadiene and an alkyl acrylate, and acrylonitrile and styrene added thereto and graft-polymerized) or an SBR elastic body (styrene-grafted polybutadiene with styrene) And the like).

The inorganic filler may be in the form of fibrous or granular or powder. Examples of the fibrous inorganic filler include glass fiber, carbon fiber, and alumina fiber. On the other hand, talc, carbon black, graphite, titanium dioxide, silica, mica, calcium carbonate, calcium sulfate, barium carbonate, magnesium carbonate, magnesium sulfate, barium sulfate, oxysulfate, tin oxide, alumina , Kaolin, silicon carbide, metal powder and the like.

Although there are various antioxidants, in particular, monophosphites such as tris (2,4-di-t-butylphenyl) phosphite and tris (mono- and di-nonylphenyl) phosphite and phosphorus such as diphosphite are preferred. An antioxidant and a phenolic antioxidant are preferred. As the diphosphite, a general formula [Wherein R ¹ and R ² each represent an alkyl group having 1 to 20 carbon atoms;
A cycloalkyl group having 3 to 20 carbon atoms or 6 to 20 carbon atoms
Represents an aryl group. It is preferable to use a phosphorus compound represented by the following formula:

Specific examples of the phosphorus compound represented by the above general formula include distearyl pentaerythritol diphosphite; dioctyl pentaerythritol diphosphite;
Diphenylpentaerythritol diphosphite; bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite; bis (2,6-di-t-butyl-4-)
Methylphenyl) pentaerythritol diphosphite; dicyclohexylpentaerythritol diphosphite;

Known phenolic antioxidants can be used, and specific examples thereof include 2,6-di-
t-butyl-4-methylphenol; 2,6-diphenyl-
4-methoxyphenol; 2,2'-methylenebis (6-t
-Butyl-4-methylphenol); 2,2'-methylenebis- (6-t-butyl-4-methylphenol); 2,2 '
-Methylenebis [4-methyl-6- (α-methylcyclohexyl) phenol]; 1,1-bis (5-t-butyl-
4-hydroxy-2-methylphenyl) butane; 2,2'-
Methylenebis (4-methyl-6-cyclohexylphenol); 2,2'-methylenebis- (4-methyl-6-nonylphenol); 1,1,3-tris- (5-t-butyl-4
-Hydroxy-2-methylphenyl) butane; 2,2-bis- (5-tert-butyl-4-hydroxy-2-methylphenyl) -4-n-dodecylmercaptobutane; ethylene glycol-bis [3,3- Bis (3-t-butyl-4-
Hydroxyphenyl) butyrate]; 1-1-bis (3,5
-Dimethyl-2-hydroxyphenyl) -3- (n-dodecylthio) -butane; 4,4'-thiobis (6-t-butyl-3-methylphenol); 1,3,5-tris (3,5- Di-t-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene; 2,2-bis (3,5-di-t-butyl-
4-hydroxybenzyl) malonic acid dioctadecyl ester; n-octadecyl-3- (4-hydroxy-3,5-
Di-t-butylphenyl) propionate; tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)] methane.

The antioxidant is based on 100 parts by weight of the styrenic polymer having a syndiotactic structure.
0.0001 to 2 parts by weight, preferably 0.001 to 1 part by weight.

Further, a metal salt of an organic acid and / or an organic phosphorus compound can be added as a crystal nucleating agent. These compounds include various compounds. Examples of the metal salt of an organic acid include benzoic acid, p- (tert-butyl) benzoic acid, cyclohexanecarboxylic acid ((hexahydrobenzoic acid),
Aminobenzoic acid, β-naphthoic acid, cyclopentanecarboxylic acid, succinic acid, diphenylacetic acid, glutaric acid, isonicotinic acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, benzenesulfonic acid, glycolic acid, caproic acid, isocaprone Metal salts such as sodium, calcium, aluminum, and magnesium salts of organic acids such as acid, phenylacetic acid, cinnamic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and oleic acid. Of these, aluminum salts of p- (tert-butyl) benzoic acid, sodium salts of cyclohexanecarboxylic acid and sodium salts of β-naphthoic acid are particularly preferred.

As the organic phosphorus compound, for example, the following general formula (Wherein, R ³ represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, R ⁴ represents an alkyl group having 1 to 18 carbon atoms, Alternatively, it indicates M _{1 / a} . M is Na, K, Mg, Ca or Al
And a represents the valence of M. ) Or a general formula (b ₁ ) (In the formula, R represents a methylene group, an ethylidene group, a propylidene group or an isopropylidene group, and R ⁵ and R ⁶ each represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.
M and a are the same as above. And the organic phosphorus compound (b ₂ ) represented by the formula:

More specific examples of the above-mentioned nucleating agents are described in Japanese Patent Application No.
No. 23745. The compounding ratio is
0.01 to 100 parts by weight of the total of the components (a) and (b)
To 15 parts by weight, preferably 0.05 to 5 parts by weight.

The resin composition of the present invention can be obtained by blending the above components (a) to (c) and, if necessary, various desired components, and kneading the mixture at an appropriate temperature, for example, 270 to 320 ° C. The compounding and kneading at this time may be performed by a usual method. Specifically, a melt kneading method using a kneader, a mixing roll, an extruder, a Banbury mixer, a Henschel mixer, a kneading roll, or a solution blending method may be used.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Reference Example 1 (mainly production of polystyrene having a syndiotactic structure) In a synthesis vessel, 32 l of toluene as a solvent and methylaluminoxane as a catalyst component as 13 aluminum as an aluminum atom were used.
35 mmol and 13.4 mmol of tetraethoxytitanium were added, followed by 15 kg of styrene.

Next, the temperature was raised to 55 ° C. to carry out a polymerization reaction for 2 hours. After the reaction, the obtained product was washed with a mixed solution of sodium hydroxide and methanol to decompose and remove the catalyst component. Then, drying was performed to obtain 2.1 kg of a polymer.

Further, this polymer was subjected to Soxhlet extraction using methyl ethyl ketone as a solvent to obtain an extraction residue of 95% by weight. This polymer had a weight average molecular weight of 400,000, a melting point of 270 ° C., and was further analyzed by nuclear magnetic resonance ( ¹³ C-NMR) of isotope carbon to find that it had a weight of 145.35 ppm due to the syndiotactic structure.
The syndiotacticity in racemic pentad calculated from the peak area was 98%.

Reference Example 2 (Production of styrene-maleic anhydride copolymer) 1,1-bis (tert-butylperoxy) was used as a polymerization initiator in 10 kg of styrene monomer and 0.35 kg of maleic anhydride.
3.68 g of 3,3,5-trimethylcyclohexane was added, and the mixture was stirred, left standing at room temperature for 24 hours, and then filtered through filter paper to obtain a raw material mixture for polymerization. After replacing the inside of the stainless steel autoclave having a capacity of 2 l with styrene monomer, the temperature was raised to 100 ° C.
The above-mentioned raw material mixture for polymerization was guided into an autoclave at a rate of 8 ml / min, and 4 l of a liquid substance was distilled out of the autoclave. The viscous liquid substance distilled out after this distillation was introduced into a large amount of hexane to precipitate a styrene-maleic anhydride copolymer resin. After removing hexane, the composition of the copolymer resin was analyzed by ¹³ C-NMR. As a result, styrene / maleic anhydride = 99/1 mol%. The weight-average molecular weight measured by gel permeation chromatography (GPC) was 200,000.

Example 1 70% by weight of polystyrene mainly having a syndiotactic structure obtained in Reference Example 1 and 30% by weight of polyamide 6 as nylon 6 (Ube Nylon 1013B manufactured by Ube Industries, Ltd.)
Is 100,000 and the weight average molecular weight is 100,000, and the copolymer composition of styrene and glycidyl methacrylate is styrene / glycidyl methacrylate = 95/5 mol%
Styrene-glycidyl methacrylate copolymer 1
Weight part, using a single screw kneading extruder having a diameter of 20 mm and a Dalmage screw with L / D = 20, 280 ° C., 50 r
After melt-kneading at pm, granulation was performed. After the pellets were injection molded, various physical properties were measured. The results are shown in Table 2. In addition, this pellet is 2.5 cm in diameter using a press molding machine,
A disc-shaped non-oriented molded product having a thickness of 4 mm was produced. The molded article was mirror-finished using a supermicrotome, etched with chromic acid, and observed in a dispersed state with a scanning electron microscope. The results are shown in Table 2. Table 1 shows the blend composition.

Examples 2-14 and Comparative Examples 1-8 Example 1 was repeated except that the blend compositions shown in Table 1 were used.
A molded article was produced in the same manner as described above, and the physical properties are shown in Table 2.

The substances used in Examples and Comparative Examples are as follows.

(A) Component SPS Polystyrene mainly having a syndiotactic structure obtained in Reference Example 1 (b) Component Nylon 6 manufactured by Ube Industries, Ltd., trade name: Ube Nylon 1013B Nylon 6.6 manufactured by Ube Industries, Ltd. Product name: PET made by Ube Nylon 2013 Polyarylate Dupont Co., Ltd. Polyethylene terephthalate manufactured by Mitsubishi Rayon Co., Ltd.
Trade name: Dianite MA-523 PBT Polybutylene terephthalate manufactured by Engineering Plastics Co., Ltd., trade name: Barox 310 (c) component ST-GMA Styrene-glycidyl methacrylate copolymer manufactured by NOF Corporation, weight average molecular weight 100,000 Styrene / glycidyl methacrylate = 95/5 mol% copolymerization ratio, trade name: Blenmer CP1005S SMA1 Styrene-maleic anhydride copolymer SMA2 manufactured in Reference Example 2 Idemitsu Petrochemical Co., Ltd. styrene-maleic anhydride copolymer Coalescence, weight average molecular weight 280,000, styrene / maleic anhydride = 86/14 mol% copolymerization ratio, trade name: Moremax UG830 PS Styrene homopolymer (manufactured by Idemitsu Petrochemical Co., Ltd.) (epoxy group or carboxylic anhydride group) ), Weight average molecular weight
300,000, Trade name: Idemitsu Polystyrene US305 Other additives GF Glass fiber, chopped strand, Asahi Fiber Glass Co., Ltd. Average fiber diameter 13 μm, average fiber length 3 mm SBS Shell Chemical Co., Ltd. Styrene-butadiene block copolymer rubber Elastomer, styrene / butadiene = 30/70% by weight, molecular weight 100,000, trade name: Kraton D1101 [Effects of the Invention] According to the present invention, as a result of improved affinity and dispersibility, there is no delamination, excellent appearance, and a polystyrene-based resin composition having improved mechanical strength undergoes a complicated process. Obtained without.

Therefore, the resin composition of the present invention is effectively used for the production of heat-resistant parts and industrial heat-resistant structural materials in automobiles, home electric appliances, electric and electronic devices, etc., and provides high-quality molded products.

Claims (4)

(57) [Claims] 1. A thermoplastic resin containing (a) 5 to 95% by weight of a styrene polymer having a syndiotactic structure and (b) at least one polar group selected from a carboxyl group, a hydroxyl group and an amino group at its terminal. Styrene-based copolymer or α, β-unsaturated carboxylic acid obtained by copolymerizing (c) 0.01 to 30 mol% of a vinyl compound having an epoxy group with respect to 100 parts by weight of a polymer mixture consisting of 95 to 5% by weight of a resin A styrene-based copolymer obtained by copolymerizing 0.01 to 5 mol% of an anhydride is used in an amount of 0.
A resin composition containing 01 to 15 parts by weight. 2. A styrenic copolymer obtained by copolymerizing a vinyl compound having an epoxy group has a weight average molecular weight of 10,000 or more.
2. The resin composition according to claim 1, which is a styrene copolymer of 800,000. 3. A styrenic copolymer obtained by copolymerizing an α, β-unsaturated carboxylic acid anhydride with a weight average molecular weight of 10,000 to 80.
2. The resin composition according to claim 1, which is a styrene-based copolymer. 4. A styrene copolymer obtained by copolymerizing (c) a vinyl compound having an epoxy group in an amount of 0.01 to 30 mol% or a styrene obtained by copolymerizing 0.01 to 5 mol% of an α, β-unsaturated carboxylic anhydride. 2. The resin composition according to claim 1, wherein the amount of the copolymer is 0.1 to 10 parts by weight.