JPH08269144A - Rubber-reinforced thermoplastic resin and thermoplastic resin composition - Google Patents

Abstract

PURPOSE: To obtain a rubber-reinforced thermoplastic resin excellent in coating performance, impact resistance and thermal stability. CONSTITUTION: This rubber-reinforced thermoplastic resin is obtained by polymerizing 80-20 pts.wt. of a monomer component comprising 30-75wt.% of an aromatic vinyl compound, 25-70wt.% of a vinyl cyanide compound and 0-30wt.% of another vinyl-based compound copolymerizable with these compounds (100wt.% of the total amounts) in the presence of 20-80 pts.wt. of a rubber-like polymer. The amount of three chains of the vinyl cyanide compound is <=11% in chains of the vinyl cyanide compound in graft chains.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having excellent coating adhesion, coating appearance, impact resistance and thermal stability.

[0002]

2. Description of the Related Art ABS resin, which is a kind of rubber-reinforced resin, is excellent in secondary workability such as chemical resistance, impact resistance, and paintability, so that it is used in the field of coating automobile parts. It is being deployed. In this case, it has been found that increasing the proportion of the graft copolymer and the vinyl cyanide compound used as a monomer component of the copolymer or the like improves the chemical resistance and the appearance at the time of coating. . However, the increase in vinyl cyanide compound reduces the adhesion of the coating film and the ease of coating during repainting.In addition, the chain formation of vinyl cyanide compound units tends to occur, resulting in a decrease in thermal stability. Or, when it was blended with other resins, it caused lumps.

[0003]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and an object thereof is to provide a resin composition excellent in coating adhesion, coating appearance, impact resistance, and thermal stability. And

[0004]

DISCLOSURE OF THE INVENTION As a result of intensive research to solve the above-mentioned drawbacks, the present invention has revealed that when the graft copolymerization of vinyl cyanide compound and aromatic vinyl compound is carried out in the presence of a rubber-like polymer, the chain length in the graft chain is Within the chain of vinyl cyanide compounds,
It has been found that the impact resistance and the thermal stability are improved by setting the ratio of 3 or more chains to 11% or less, and the present invention has been completed based on this finding. That is, in the present invention, in the presence of 20 to 80 parts by weight of the rubber-like polymer (A) (A), 30 to 75% by weight of the aromatic vinyl compound (a-1) and the vinyl cyanide compound (b-1) 25 are used. ˜70% by weight, other vinyl compound (c-
1) 0 to 30% by weight (however, (a-1) + (b-1)
+ (C-1) = 100% by weight] 80 to 20 parts by weight of the monomer component (b) [where (a) + (b) = 1]
00 parts by weight], the intrinsic viscosity [η] (measured in dimethylformamide at 30 ° C.) of the acetonitrile-soluble component is 0.27 to 0.7, and the graft ratio is 25 to 15
0%, the content of vinyl cyanide component in the polymer soluble in acetonitrile is 28 to 45% by weight, and the proportion of 3 or more chains among vinyl cyanide compound chains in the graft chain length is 11%. The following are rubber reinforced thermoplastics. And (B) the above-mentioned rubber-reinforced thermoplastic resin (A)
10 to 99 parts by weight of aromatic vinyl compound (a-2) 3
0-75% by weight, vinyl cyanide compound (b-2) 25
˜70% by weight, vinyl compound (c
-2) 0 to 30% by weight (however, (a-2) + (b-
2) + (c-2) = 100% by weight] copolymer (B) 9
A thermoplastic resin composition comprising 0 to 1 part by weight (however, (A) + (B) = 100 parts by weight). Is provided.

The present invention will be described in detail below. Examples of the rubber-like polymer (a) used for the rubber-reinforced thermoplastic resin (hereinafter sometimes referred to as “A component”) of the present invention include polybutadiene, polyisoprene, butyl rubber, styrene-butadiene copolymer (styrene content of 5 to 5). 60% by weight is preferable), styrene-isoprene copolymer, acrylonitrile-butadiene copolymer, ethylene-α-
Olefin copolymer, ethylene-α-olefin-polyene copolymer, silicone rubber, acrylic rubber, butadiene- (meth) acrylic acid ester copolymer, polyisoprene, styrene-butadiene block copolymer, styrene-isoprene block copolymer The polymers, styrene-butadiene block copolymers, and styrene-isoprene block copolymers include those having structures of AB type, ABA type, taper type, radial teleblock type, and the like. Further, the hydrogenated butadiene-based polymer is, in addition to the above block copolymer, a hydride of a block of a styrene block and a styrene-butadiene random copolymer, and a 1,2-vinyl bond content in polybutadiene of 20% by weight. % Of blocks and hydrides of polymers consisting of polybutadiene blocks having a 1,2-vinyl 1,2-vinyl bond content of more than 20% by weight.

The preferred rubbery polymer is a diene rubbery polymer. The diene rubber-like polymer is preferably a diene rubber-like polymer obtained by polymerizing one or more kinds of monomers having a conjugated diene content of 50% by weight or more, more preferably 70% by weight or more. As the conjugated diene that constitutes the diene rubber-like polymer, butadiene, isoprene, chloroprene and the like can be used, and among these, butadiene is preferable.

Examples of the monomer copolymerizable with the conjugated diene include aromatic vinyl, unsaturated carboxylic acid, methacrylic acid alkyl ester, acrylic acid alkyl ester, vinyl cyanide, N-substituted maleimide, and polyfunctional monomer. And so on. The copolymerization content of the conjugated diene in the diene rubbery polymer is preferably 50% by weight or more because the thermoplastic resin has excellent impact resistance at low temperatures.

In the polymerization of the rubbery polymer, generally used emulsifiers, electrolytes, polymerization regulators, polymerization initiators and the like can be used. As the emulsifier, an alkali metal salt of rosin acid, an alkali metal salt of fatty acid, an alkali metal salt of aliphatic alcohol sulfuric acid ester, an alkali metal salt of alkylallyl sulfonic acid, an alkali metal salt of dialkyl sulfosuccinate ester, polyoxyethylene alkyl (phenyl ) Ether sulfate alkali metal salts, polyoxyethylene alkyl (phenyl) ether phosphate ester alkali metal salts, and the like, and electrolytes include sulfuric acid, phosphoric acid, hydrochloric acid, carbonic acid alkali metal salts, and the like. Are used alone or in combination of two or more.

As the polymerization regulator, mercaptans, terpenes, halides and the like can be added as necessary, and as the polymerization initiator, persulfates, organic hydroperoxides, or organic hydroperoxides can be added. A redox catalyst or the like, which is a combination of a reducing agent and a reducing agent, can be preferably used.

The rubber-like polymer may be polymerized by batch addition polymerization of monomers, continuous addition polymerization, multi-stage polymerization, for example, specific composition, specific addition of specific amounts of monomers Generally widely known emulsion polymerization methods such as continuous addition polymerization of monomers and multi-step polymerization in which the composition of each stage is changed can be applied.

The rubber-like polymer may be, for example, a mixture of one or more rubber-like polymers having different toluene insoluble components, a mixture of one or more rubber-like polymers having different latex average particle diameters, or a monomer composition. It may be a mixed latex of a plurality of rubber-like polymers such as a mixture of one or more different rubber-like polymers. The amount of the rubber-like polymer (a) used is 20 to 80 parts by weight [monomer component (b) is 20 to 80 parts by weight], preferably 30 to 70 parts by weight [monomer component (b) is 30-7
0 parts by weight] More preferably 35 to 65 parts by weight [monomer component (b) is 35 to 65 parts by weight].

When the amount of the rubber-like polymer used is less than 20 parts by weight [the monomer component (b) exceeds 80 parts by weight],
A large amount of the graft copolymer to be blended is required, and as a result, the blendable amount of the copolymer is small,
If the coating film adhesion decreases and the amount exceeds 80 parts by weight [monomer component (b) is less than 20 parts by weight], moldability and thermal stability are deteriorated, which is not preferable. In particular, the amount of rubbery polymer used is 40
When it is from 60 parts by weight, the balance between the coating appearance and the coating film adhesion is further improved.

Next, the monomer components used for the copolymerization of the graft copolymer of the present invention will be described. Examples of the aromatic vinyl monomer (a-1) used in the component (A) include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene and bromo. Examples thereof include styrene, vinyl pyridine, vinyl xylene, fluorostyrene, and ethylstyrene, and styrene and α-methylstyrene are particularly preferable.
Vinyl cyan monomer (b-1) used in component (A)
Examples thereof include acrylonitrile and methacrylonitrile, which may be used alone or in combination of two or more. Examples of the other vinyl monomer (c-1) copolymerizable with the aromatic vinyl compound used here include (meth) acrylic acid alkyl ester, maleimide-based compound, unsaturated acid, and acid anhydride group-containing unsaturated group. There are saturated compounds, epoxy group-containing unsaturated compounds, hydroxyl group-containing unsaturated compounds, amino group-containing unsaturated compounds and oxazoline group-containing unsaturated compounds, and these are used alone or in combination of two or more.

As the (meth) acrylic acid ester, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amino acrylate,
Acrylic esters such as hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, benzyl acrylate: methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amino methacrylate, hexyl methacrylate, octyl Methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, methacrylic acid ester such as benzyl methacrylate, and the like are used, and these are used alone or in combination of two or more. Examples of the maleimide compound include maleimide compounds of α, β-unsaturated dicarboxylic acids such as maleimide, N-methylmaleimide, N-butylmaleimide, N- (p-methylphenyl) maleimide, N-phenylmaleimide and N-cyclohexylmaleimide. Used alone or in combination of two or more.

Examples of unsaturated acids include acrylic acid, methacrylic acid and maleic acid. Examples of the unsaturated compound containing an acid anhydride group include maleic anhydride, citraconic anhydride, and itaconic anhydride. Examples of the epoxy group-containing unsaturated compound include glycidyl methacrylate and allyl glycidyl ether. Examples of the amino group-containing unsaturated compound include acrylic amine, aminoethyl methacrylate, aminopropyl methacrylate, aminostyrene, acrylamide, and methacrylamide. As the hydroxyl group-containing unsaturated compound, hydroxystyrene, 3-
Hydroxy-1-propene, 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4
-Hydroxy-2-butene, 3-hydroxy-2-methyl-1-propene, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and the like.
Examples of the oxazoline group-containing unsaturated compound include vinyl oxazoline.

Monomer component (b) used as component (A)
The ratio of the aromatic vinyl compound (a-1) used is 75 to
30% by weight, preferably 70 to 35% by weight, more preferably 67 to 40% by weight, particularly preferably 65 to 45% by weight. The proportion of the vinyl cyanide compound (b-1) used is 25 to 70% by weight, preferably 30 to 65% by weight,
More preferably 33 to 60% by weight, particularly preferably 3
5 to 55% by weight. The proportion of the other copolymerizable vinyl compound (c-1) used is 0 to 30% by weight, preferably 0 to 25% by weight, more preferably 0 to 20% by weight, and particularly preferably 0 to 15% by weight. is there. (B-1) is 25
If it is less than wt% [(a-1) exceeds 75 wt%], the coating appearance is deteriorated. On the other hand, (b-1) is 70% by weight
When [(a-1) is less than 30% by weight], the ratio of 3 or more chains of vinyl cyanide compound in the graft chain is 11% of chains derived from the vinyl cyanide compound in the graft body. Is exceeded, and the thermal stability decreases, which is not preferable. The graft copolymer (A) of the present invention can be obtained by polymerizing the monomer component (B) in the presence of the rubber-like polymer (A). Polymerization can be usually carried out by suspension polymerization, emulsion polymerization, preferably emulsion polymerization, in the same manner as in the case of the rubber-like polymer. As the polymerization initiator, the emulsifier, and the polymerization initiator, the same general ones as those used for producing the rubber-like polymer can be used. However, it is not limited to these.

As the chain transfer agent used in the graft copolymerization, terpenoid compounds represented by terpinolene which is a hydrocarbon compound, aromatic compounds represented by α-methylstyrene dimer and the like are preferable, and particularly, Terpenoid compounds are preferred. The use of a mercaptan-based compound is not preferable because the ratio of three chains of the vinyl cyanide compound in the graft chain increases. Even when a mercaptan chain transfer agent is used in combination, the hydrocarbon chain transfer agent is preferably 30% or more, more preferably 40% or more, and particularly preferably 50% of all chain transfer agents.
%, The proportion of vinyl cyanide compounds having 3 or more chains is easily controlled to 10% or less, which is preferable.

As a method of adding the monomer during the polymerization of the component (A), generally known methods such as batch addition, continuous addition, and multi-step addition in which the composition of each stage is changed are adopted. You can The component (A) is dried and made into a powder through a recovery process such as coagulation and washing. The unbound copolymer (acetonitrile-soluble component) in the component (A) of the present invention
The intrinsic viscosity [η] is preferably 0.27 to 0.7, more preferably 0.28 to 0.65, still more preferably 0.29 to 0.6, and particularly preferably 0.3 to 0. It is 5. When the intrinsic viscosity is less than 0.27, the balance between rigidity and impact resistance cannot be obtained, while when it exceeds 0.7, the molding processability is deteriorated, and seeds are generated, which is not preferable. The intrinsic viscosity [η] is measured by the following method. The free copolymer was isolated, dissolved in dimethylformamide and heated at 30 ° C.
The temperature was measured with an Ubbelohde viscometer.

The content of the vinyl cyanide component in the acetonitrile-soluble polymer as the component (A) is 28 to 45% by weight, preferably 29 to 43% by weight, more preferably 30 to 42% by weight, It is particularly preferably 32 to 40% by weight.

The graft ratio of the component (A) is 25 to 150% by weight, preferably 30 to 120% by weight, more preferably 35 to 100% by weight, and particularly preferably 40 to 80% by weight. If the graft ratio is less than 25% by weight, impact resistance tends to be low, which is not preferable. Again 150
If it exceeds 5% by weight, lumps are generated, which is not preferable. Here, the graft ratio means the ratio of the copolymer component directly graft-bonded to the rubber-like polymer to the rubber amount of the graft copolymer. This graft ratio can be controlled by the amount of polymerization initiator, the polymerization temperature, and the like. The specific method of determining the graft ratio is to first add 2 g of the component (A) of the present invention to N, N, dimethylformamide at room temperature and stir sufficiently to determine the insoluble matter (w). On the other hand, the rubber-like polymer in insoluble decomposition (w) can be calculated based on the polymerization prescription. Let R be the calculated total amount of the rubber-like polymer, and obtain the graft ratio from the following formula. Graft ratio (% by weight) = [(w−R) / R] × 100 Further, the ratio of 3 or more chains among vinyl cyanide compound chains in the graft chain length of the component (A) of the present invention is 1
It is 1% or less, preferably 1 to 10%, more preferably 2 to 9%. If the proportion of the three chains of the vinyl cyanide compound in the graft chain length exceeds 11%, the thermal stability is deteriorated, and lumps are likely to occur during extrusion or molding, which is not preferable.

Next, the copolymer (B) according to claim 2 of the present invention will be explained. Aromatic vinyl compound (a-2), vinyl cyanide compound (b-2), which is a monomer used in the copolymer (B), and other vinyl compound (c-2) that can be copolymerized. As described in (A) component (a
-1), (b-1), and (c-1). The proportion of the aromatic vinyl compound (a-2) used in the copolymer (B) component is 30 to 75% by weight, preferably 70 to 35% by weight, more preferably 67 to 40% by weight, and particularly preferably 65 to 65% by weight. It is 45% by weight. The usage ratio of the vinyl cyanide compound (b-2) is 25 to 70% by weight, preferably 30 to 65% by weight, more preferably 33 to 60% by weight, and particularly preferably 35 to 55% by weight. The other copolymerizable vinyl compound (c-2) is 0 to 30% by weight,
Preferably 0 to 25% by weight, more preferably 0 to 20
%, Particularly preferably 0 to 15% by weight. (B-
When 2) is less than 25% by weight [(a-2) exceeds 75% by weight], the coating appearance becomes poor, while when it exceeds 70% by weight [(a-2) is less than 30% by weight], the coating adheres. Property is deteriorated, thermal stability is deteriorated, and coloring is facilitated.

The component (B) is usually produced by solution polymerization or emulsion polymerization. Here, a preferred polymerization method in solution polymerization or emulsion polymerization depends on the monomer composition ratio and the monomer reaction ratio in the reaction system, and the copolymerization reaction proceeds from the reaction system having a certain monomer composition ratio. Except when the monomer composition ratio is the azeotropic composition, the composition ratio of the unreacted monomer and the composition of the copolymer produced therefrom change with the progress of the copolymerization reaction. Therefore, in order to produce a copolymer (B) having a uniform composition, an initial charge is performed at a monomer composition ratio suitable for the monomer reactivity ratio to start the copolymerization reaction, and thereafter As the reaction progresses, the aromatic vinyl compound, which is a monomer with a high reaction consumption rate, is additionally supplied to the reaction system, so that the monomer composition ratio of the copolymerization reaction system is kept almost constant until the completion of the copolymerization reaction. It is important to maintain.

As a medium for solution polymerization, toluene, acetonitrile, dimethylformamide, etc. can be used,
As the polymerization initiator, paramenthane hydroperoxide, benzoyl peroxide, lauroyl peroxide and the like, or by thermal polymerization, further as a chain transfer agent, mercaptans, hydrocarbons and the like is used, further as a polymerization temperature, Mercaptan and hydrocarbon are used, and the polymerization temperature is 60 to 1
It is about 50 ° C. The copolymer (B) undergoes a recovery process such as coagulation, washing, and desolvation, and is dried into powder or granules. The molecular weight of the copolymer (B) depends on its intrinsic viscosity [η].
Is preferably 0.2 to 0.9 dl / g, more preferably 0.25 to 0.8 dl / g, particularly preferably 0.3 to
It is 0.7 dl / g. When the intrinsic viscosity is less than 0.2, impact resistance is lowered, and when it exceeds 0.9, molding processability is lowered, which is not preferable. The intrinsic viscosity was measured by dissolving in methyl ethyl ketone and measuring with an Ubbelohde viscometer under the temperature condition of 30 ° C.

The content of the vinyl cyanide component in the acetonitrile-soluble polymer as the component (B) is preferably 20.
-50% by weight, more preferably 23-45% by weight, further preferably 25-43% by weight, particularly preferably 27-
It is 40% by weight. The proportion of vinyl cyanide compound chains in the component (B) having 3 or more chains is preferably 15% or less, more preferably 1 to 11%, and particularly preferably 2 to 10%.

Next, the compounding ratio of the composition of the components (A) and (B) will be described. The mixing ratio of the component (A) is 10 to 99 parts by weight, preferably 15 to 90 parts by weight, more preferably 20 to 80 parts by weight, and particularly preferably 25 to 70 parts by weight. The blending ratio of the copolymer (B) is 90 to 1 part by weight, preferably 85 to 10 parts by weight, more preferably 80 to 20 parts by weight, and particularly preferably 75 to
30 parts by weight. When the amount of the component (A) is less than 10 parts by weight [the amount of the component (B) is more than 90 parts by weight], the impact resistance is insufficient and the coating film adhesion is insufficient. Further, the amount of the component (A) is 99 parts by weight or less [the amount of the component (B) is 1
When it is at least part by weight], the gloss and processability are improved, which is preferable.

Other known polymers may be added to the resin composition of the present invention. Examples of the polymer that can be blended include ethylene-propylene copolymer, EPDM,
Styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer and hydrogenated product, styrene-butadiene-styrene radial teleblock copolymer and hydrogenated product, polypropylene, butadiene-acrylonitrile copolymer, polyvinyl chloride ,
Polycarbonate, PET, PBT, polyacetal,
Polyamide, polyamide elastomer, epoxy resin,
Polyvinylidene fluoride, polysulfone, ethylene-vinyl acetate copolymer, polyisoprene, natural rubber, chlorinated butyl rubber, chlorinated polyethylene, PPE resin, PPS resin, polyether ether ketone, styrene maleic anhydride copolymer, polyamide elastomer, etc. You may blend and use it suitably.

The following additives may be added to the composition of the present invention, if desired. Antioxidants such as 2,6-
Di-t-butyl-4-methylphenol, 2- (1-methylcyclohexyl) -4,6-dimethylphenol,
2,2'-methylene-bis- (4-ethyl-6-t-butylphenol), 4,4'-thiobis- (6-t-butyl-3-methylphenol), dilaurylthiodipropionate, tris ( Di-nonylphenyl) phosphite, wax; UV absorbers such as p-t-butylphenyl salicylate, 2,2'-dihydroxy-4-methoxybenzophenone 2- (2'-hydroxy-4'-
n-octoxyphenyl) benzotriazole; lubricant,
For example, paraffin wax, stearic acid, hydrogenated oil, stearamide, methylene bis stearamide, ethylene bis stearamide, n-butyl stearate, ketone wax, octyl alcohol, lauryl alcohol,
Hydroxystearic acid triglyceride; flame retardants such as antimony oxide, aluminum hydroxide, zinc borate,
Tricresyl phosphate, tris (dichloropropyl) phosphate, chlorinated pariphine, tetrabromobutane, hexabromobenzene, tetrabromobisphenol A; antistatic agents such as stearoamidopropyldimethyl-β-hydroxyethylammonium nitrate; colorants For example, titanium oxide, carbon black; fillers such as calcium carbonate, clay, silica, glass fibers, glass spheres, carbon fibers; pigments and the like can be added if necessary.

The resin composition of the present invention can be obtained by kneading the components using various extruders, Banbury mixers, kneaders, rolls and the like. A preferred manufacturing method is a method using a twin-screw extruder. Moreover, when kneading each component, you may knead all components collectively, and you may knead them by a multistage addition system. The resin composition of the present invention thus obtained can be molded into various molded articles by injection molding, sheet extrusion, vacuum molding, profile molding, foam molding, blow molding and the like. Various molded products obtained by the above-mentioned molding method can be used for various parts and parts such as automobile parts and home electric appliances by utilizing their excellent properties.

[0029]

EXAMPLES The present invention will be specifically described by the following examples, which do not limit the scope of the present invention. Reference Example 1 Production of component (A) Polybutadiene rubber latex (solid content) 50 parts by weight Potassium rosinate 1.3 parts by weight Styrene 5 parts by weight Acrylonitrile 5 parts by weight Terpinolene 0.1 parts by weight Deionized water 125 parts by weight or more The ingredients were placed in a flask and stirred at a temperature of 50 ° C. under a nitrogen stream. As an initiator, sodium pyrophosphate 0.4 parts by weight ferrous sulfate 0.008 parts by weight Dextrose 0.5 parts by weight as an aqueous solution. Then, 0.2 part by weight of cumene hydroxyperoxide was added to the flask as it was, the polymerization was started, the following monomer mixture was continuously added over 5 hours, and after the addition was completed, the mixture was further heated at 70 ° C. for 1 hour. The reaction was allowed to complete the polymerization. Styrene 22 parts by weight Acrylonitrile 18 parts by weight Terpinolene 0.1 parts by weight Cumene hydroxyperoxide 0.23 parts by weight The final polymerization addition rate of the obtained latex of the component (A) is 9 parts by weight.
4%. The latex of component (A) was coagulated with sulfuric acid, washed with water and dried to obtain a powder polymer. Table 1 shows each physical property of the component (A).

[0030]

[Table 1]

Reference Example 2 (A) Production of Components A-2 to 10 Component (A) was prepared in the same manner as in Reference Example 1 except that the monomer component, polymerization temperature, polymerization initiator, molecular weight modifier and the like were changed. Was obtained and its physical properties were evaluated in the same manner as in Reference Example 1. The results are shown in Table 1.

Reference Example 3 Production of Copolymer B-1 Styrene 68 parts by weight Acrylonitrile 32 parts by weight Toluene 60 parts by weight tert-dodecyl mercaptan 0.3 parts by weight The above components were charged in a stainless steel reactor under a nitrogen atmosphere. While stirring, the temperature was raised to 140 ° C. to start the polymerization reaction. Then, the reaction was allowed to proceed for 2 hours to complete the polymerization. The polymerization addition rate after polymerization was 96%. The obtained copolymer solution was stripped, pulverized and dried to obtain a copolymer.

Reference Example 4 Production of Copolymers B-2 to 5 The procedure of Reference Example 3 was repeated except that the ratios of acrylonitrile and styrene were changed to obtain copolymers having the ratios shown in Table 2. Obtained.

[0034]

[Table 2]

Example 1 35 parts by weight of (A-1) obtained in Reference Example 1 and 65 parts by weight of the copolymer (B-1) obtained in Reference Example 3 were mixed and premixed with a Henschel mixer. This was melt-kneaded and pelletized using a twin-screw extruder. The pellets were visually inspected and the presence or absence of spots was measured. Next, the pellets were molded using an injection molding machine (MS-32 manufactured by Meiki Seisakusho Co., Ltd.).
A test piece was prepared and evaluated for impact resistance and thermal stability.
The impact resistance evaluation sample was molded at 220 ° C, and the thermal stability evaluation sample was molded at 260 ° C. Furthermore, using an injection molding machine (Toshiba Machinery Co., Ltd. IS-125CN-II),
A flat plate test piece was prepared and the paintability was evaluated. The evaluation results are shown in Table 3.

[0036]

[Table 3]

(1) Coating test: Flat plate test piece (160 mm
X 100 mm x 3 mm), urethane coating (Soflex: Kansai Paint) with a film thickness of about 75 μm (after drying)
After spray coating and drying so as to obtain the following, the appearance of the coated surface and the adhesion of the coating film were evaluated. (1-1) Appearance Evaluation of Painted Surface The paint appearance was evaluated by visually observing three-stage evaluation of color unevenness occurring on the surface after the coating film was dried. (1-2) Adhesion of coating film The adhesion of the coating film is 1 mm × 1 with a cutter after the coating film is dried.
A crosscut of mm was performed on a test piece, this was washed with water using a water jet, the area of the coating film remaining on the test piece was measured, and the adhesion was evaluated by the ratio of the area remaining. (2) Impact resistance (Izod impact strength): ASTM D
-256. (Notched, thickness 1/4
Inch) (3) Thermal stability (Izod impact strength): ASTM D
-256. (Notched, thickness 1/4
Inch) (4) Chain ratio of vinyl cyanide compound ¹³ C-NMR measurement was carried out to obtain C of vinyl cyanide compound.
The chain ratio of the vinyl cyanide compound was measured by the ratio of the chemical shift intensities of N-bonded carbons.

Examples 2 to 7 and Comparative Examples 1 to 5 The resin composition was prepared by changing only the component (A) and the copolymer (B) obtained in Reference Example, and the procedure was performed in Example 1. The physical properties were measured by the same method as. The measurement results are shown in Table 3.

As is clear from Table 3, Examples 1 to 7
Is within the range of the present invention, and has good impact resistance, thermal stability, and paintability. In contrast, the components (A) A-8 to A-12 used in Comparative Examples are outside the scope of the claims of the present invention. Comparative Example 1 is the case where the content of the vinyl cyanide compound as the component (A) is lower than that of the present invention, and Comparative Example 2 is the case where the content is conversely higher than that of the present invention. Neither of them has good paintability and impact resistance. Comparative Examples 3 and 5 are (A) component A-10 and A-12.
Since the ratio of the three chains of the vinyl cyanide compound of 1 is too large, good thermal stability cannot be obtained. In Comparative Example 4, since the [η] of the component (A) is too low than the range of the present invention, good impact resistance is not obtained.

[0040]

The rubber-reinforced thermoplastic resin of the present invention is excellent in secondary workability such as paintability, impact resistance, and thermal stability, and is useful in a wide range of applications such as vehicles and home appliances.

Front Page Continuation (72) Inventor Kazuki Iwai 2-11-24 Tsukiji, Chuo-ku, Tokyo Nihon Gosei Rubber Co., Ltd.

Claims (2)

[Claims] 1. An aromatic vinyl compound (a-1) 30 to 75% by weight and a vinyl cyanide compound (b-1) 25 to 70% by weight in the presence of 20 to 80 parts by weight of a rubbery polymer (a). %, Other vinyl-based compounds (c-
1) 0 to 30% by weight (however, (a-1) + (b-1)
+ (C-1) = 100% by weight] 80 to 20 parts by weight of the monomer component (b) [where (a) + (b) = 1]
00 parts by weight], the intrinsic viscosity [η] (measured in dimethylformamide at 30 ° C.) of the acetonitrile-soluble component is 0.27 to 0.7, and the graft ratio is 25 to 150.
%, The content of the vinyl cyanide component in the acetonitrile-soluble polymer is 28 to 45% by weight, and the ratio of 3 or more chains of vinyl cyanide compound chains in the graft chain length is 11% or less. Is a rubber reinforced thermoplastic resin. 2. A rubber-reinforced thermoplastic resin (A) according to claim 1 in an amount of 10 to 99 parts by weight, and an aromatic vinyl compound (a-).
2) 30 to 75% by weight, vinyl cyanide compound (b-
2) 25 to 70% by weight, 0 to 30% by weight of a vinyl compound (c-2) copolymerizable therewith (however, (a-2) +
(B-2) + (c-2) = 100% by weight] 90 to 1 part by weight of the copolymer (B) [however, (A) + (B) = 10]
0 part by weight]. [0001]