JPH08193106A - Rubber-modified thermoplastic resin and composition thereof - Google Patents

Abstract

PURPOSE: To obtain a rubber-modified therfnoplastic resin suitable for use as a blending resin for imparting excellent performance to other resins. CONSTITUTION: The resin is obtained by polymerizing an aromatic vinyl compound (b) with a vinyl cyanide compound (c) in the presence of a rubbery polymer (a). It has a content of the ingredient (a) of 50-80wt.%, a content of the ingredient (b) of 2-48wt.%, a content of the ingredient (c) of 2-45wt.%, a Q value of 30×10<-4> to 50×10<-3> cc/sec, and a grafting percentage of 5wt.% or higher.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is blended with other resins,
The present invention relates to a rubber-modified thermoplastic resin suitable for imparting excellent performance, and a composition comprising the rubber-modified thermoplastic resin and another thermoplastic resin.

2. Description of the Related Art ABS resins and AES resins are widely known as rubber-modified thermoplastic resins and are industrially used in large quantities. The following two methods are generally known as methods for producing an ABS resin. A method of polymerizing 75 to 95% by weight of a monomer composed of styrene and acrylonitrile in the presence of 5 to 25% by weight of a rubbery polymer. ABS resin having a high rubber content (hereinafter referred to as "rubber-rich ABS resin") obtained by polymerizing 55 to 60% by weight of a monomer composed of styrene and acrylonitrile in the presence of 40 to 45% by weight of a rubber-like polymer, Blended with a styrene-acrylonitrile copolymer (AS resin) obtained by separate polymerization, and the content of the rubber-like polymer in the blend is 5 to 25% by weight.
To obtain an ABS resin by adjusting to (the ABS resin obtained by this method is hereinafter referred to as "blend type ABS resin"
That). In the above method, by appropriately selecting the compounding amount of the rubber-rich ABS resin and appropriately selecting the type of AS resin, various kinds of ABS resins having different qualities can be produced with high productivity. However, further cost reduction is required in the ABS industry. As a measure to reduce the cost, the rubber content of the rubber-rich ABS resin is further increased, and the blending amount of the AS resin which is excellent in productivity and low in cost is increased to improve the blend type A.
A method of increasing the productivity of BS resin can be considered. But,
In our study, if the rubber content of rubber-rich ABS resin is increased compared to the conventional product, blend type A using it
The BS resin is conspicuously defective in that fish eyes are generated, and the appearance and impact resistance of the molded product are inferior to those of the blend type ABS resin using the conventional rubber-rich type ABS (resin). Further, the rubber-rich ABS resin is used by being blended with other thermoplastic resins in addition to the AS resin, but when the rubber content of the rubber-rich ABS resin is increased, the same problems as described above were observed. .

SUMMARY OF THE INVENTION The present invention provides a rubber-rich ABS resin having a high rubber content and having a high rubber content, which solves the above-mentioned problems.
An object is to provide a thermoplastic resin composition comprising the rubber-rich ABS resin and another thermoplastic resin.

[0002]

Means for Solving the Problems The inventors of the present invention have diligently studied how to solve the above-mentioned problems caused by a rubber-rich ABS resin having a rubber content of 50 to 80% by weight.
Q value of 80 wt% rubber-rich ABS resin is 30 × 10
The inventors have found that the above-mentioned problems can be solved by modifying so that it becomes ⁻⁴ to 50 × 10 ⁻³ cc / sec, and arrived at the present invention. That is, the present invention is obtained by polymerizing an aromatic vinyl compound (b) and a vinyl cyanide compound (c) in the presence of the rubbery polymer (a) component, and the content of the component (a) is 50 to 50%. 80% by weight, the content of the component (b) is 5 to 48
%, The component (c) is 2 to 45% by weight, the Q value defined in the text is 30 × 10 ⁻⁴ to 50 × 10 ⁻³ cc / sec, and the graft ratio is 5% by weight or more. A rubber-modified thermoplastic resin, and a composition comprising the rubber-modified thermoplastic resin (A) according to claim 1 and another thermoplastic resin (B), wherein the content of the component (a) in the composition is 3 to 35% by weight
Which is a thermoplastic resin composition. Hereinafter, the present invention will be described in detail. The rubber-modified thermoplastic resin (A) of the present invention is obtained by polymerizing an aromatic vinyl compound (b) and a vinyl cyanide compound (c) in the presence of a rubber-like polymer (a) component, and rubber-modified Thermoplastic resin (A)
The content of the component (a) is 50 to 80% by weight, the content of the component (b) is 5 to 48% by weight, and the content of the component (C) is 2.
~ 45 wt%, Q value is 30 x 10 ^-4 to 50 x 10 ^-3 cc /
Second, a rubber-modified thermoplastic resin having a graft ratio of 5% by weight or more.

Examples of the rubbery polymer as the component (a) used in the present invention include polybutadiene, polyisoprene and 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, acrylic rubber, butadiene-
(Meth) acrylic acid ester copolymer, polyisoprene, styrene-butadiene block copolymer, styrene-isoprene block copolymer, hydrogenated styrene-butadiene block copolymer, hydrogenated butadiene-based polymer,
Examples include ethylene ionomers. The styrene-butadiene block copolymer and the styrene-isoprene block copolymer include those having an AB type, ABA type, taper type, radial teleblock type structure, and the like. Further, the hydrogenated butadiene-based polymer has, in addition to the hydride of the 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. Included are hydrides of polymers composed of blocks of 20% by weight or less and polybutadiene blocks having a 1,2-vinyl bond content of more than 20% by weight. These rubber-like polymers are used alone or in combination of two or more.
The preferred component (a) is at least one conjugated diene rubber selected from polybutadiene and styrene-butadiene (styrene content is preferably 5 to 60% by weight) copolymer, more preferably polybutadiene / styrene-. Butadiene copolymer: 50 to 99/1 to 50
(% By weight). Examples of the aromatic vinyl compound as the component (b) include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene,
N, N-diethyl-p-aminoethylstyrene, N, N
-Diethyl-p-aminomethylstyrene, vinylpyridine, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene, fluorostyrene, ethylstyrene, vinylnaphthalene and the like are mentioned, and styrene and α-methylstyrene are particularly preferable. These aromatic vinyl compounds may be used alone or in combination of two or more. Examples of the vinyl cyanide compound as the component (c) include acrylonitrile and methacrylonitrile.

For the purpose of the present invention, other monomers can be used within a range that does not interfere. As other monomers, for example, methyl acrylate, ethyl acrylate,
Acrylic esters such as propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, and benzyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate. , Butyl methacrylate, amyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, benzyl methacrylate and other methacrylic acid esters; maleic anhydride, itaconic anhydride, anhydrous silane. Unsaturated acid anhydrides such as Rakon acid;
Unsaturated acids such as acrylic acid and methacrylic acid; maleimide, N-methylmaleimide, N-butylmaleimide, N
-(P-Methylphenyl) maleimide, N-phenylmaleimide, N-cyclohexylmaleimide and other α- or β-unsaturated dicarboxylic acid imide compounds (also referred to as maleimide monomers); glycidyl methacrylate, allyl glycidyl ether, etc. Epoxy compounds; unsaturated carboxylic acid amides such as acrylamide and methacrylamide; amino group-containing unsaturated compounds such as acrylamine, aminomethyl methacrylate, aminoethyl methacrylate, aminopropyl methacrylate and aminostyrene,
3-hydroxy-1-propene, 4-hydroxy-1-
Butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, 3-hydroxy-2-
Examples thereof include a hydroxyl group-containing unsaturated compound such as methyl-1-propene, 2-hydroxyethyl acrylate, and 2-hydroxyethyl methacrylate; and an oxazoline group-containing unsaturated compound such as vinyloxazoline. These monomers are used alone or in combination of two or more. The content of other monomers is preferably 20 in the components excluding the component (a).
It is not more than 10% by weight, more preferably not more than 10% by weight.
The content of the component (a) in the rubber-modified thermoplastic resin (A) is 50 to 80% by weight, preferably 52 to 75% by weight, and more preferably 56 to 74% by weight. If the content of the component (a) is less than 50% by weight, the productivity improving effect is not sufficient, while if it exceeds 80% by weight, fisheyes are more likely to be generated and the appearance and impact resistance are greatly improved. Fall to. The content of the component (b) in the rubber-modified thermoplastic resin (A) is 5 to 48% by weight, preferably 5 to 46% by weight, more preferably 13 to 41% by weight. The content of the component (c) is 2-45% by weight, preferably 2-43% by weight, more preferably 3-31% by weight. Any of the case where the component (b) is less than 2% by weight, the component (b) exceeds 48% by weight, the component (c) is less than 2% by weight, and the component (c) exceeds 45% by weight. Also in this case, at least one of the effect of improving the defective phenomenon of fisheye generation, the effect of improving the appearance and the effect of improving the impact resistance is not sufficient, and it is not possible to maintain the three of them at a target level.

The Q value of the rubber-modified thermoplastic resin (A) is 30.
X10 ^-4 to 50x10 ^-3 cc / sec, preferably 50x10
^-4 to 40 x 10 ^-3 cc / sec, more preferably 70 x 10
^-4 to 40 x 10 ^-3 cc / sec. When the Q value is less than 30 × 10 ^{−4 or more} than 50 × 10 ⁻³ , fisheyes are frequently generated, appearance is poor, and impact resistance is not sufficient. The measurement conditions for the Q value are shown below. (1) The resin used for measurement is adjusted to have a volatile substance content of 0.1% by weight or less under the condition of 110 ° C. × 60 minutes. (2) Q value measurement conditions Measuring device: Shimadzu flow tester CAPILLARY R
HEOMETER CFT-500 Measurement conditions: Sample amount: 1.8 g Plunger area: 1.0 cm ² Die size: 2.0 mm length x 1.0 mmφ Preheating temperature and time: 200 ° C x 5 minutes Measurement temperature: 200 ° C Load Weight: 60kg / cm ²

The graft ratio of the rubber-modified thermoplastic resin (A) is 5% by weight or more, preferably 10% by weight or more. If the graft ratio is less than 5% by weight, many fisheyes are generated and the appearance and impact resistance are poor. The graft ratio is measured by the following method. Here, the graft ratio means the ratio of the copolymer component directly graft-bonded to the rubber-like polymer to the amount of rubber in the rubber-modified thermoplastic resin. This graft ratio can be controlled by the amount of polymerization initiator, the polymerization temperature, and the like. The specific method of obtaining this graft ratio is
First, 2 g of the rubber-modified thermoplastic resin (A) of the present invention is put into acetone at room temperature and sufficiently stirred to obtain an insoluble matter (w). On the other hand, the amount of the rubber-like polymer in the insoluble matter (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 amount (% by weight) = [(w−R) / R] × 100

The contents of the components (a), (b), and (c) in the rubber-modified thermoplastic resin (A) can be adjusted appropriately by adjusting the charged amounts of those components during polymerization. The contents of the components (a), (b), and (c) in the rubber-modified thermoplastic resin (A) can be determined from the charged amounts of those components and the polymerization conversion rate. As another method, a known quantitative analysis method can be used. The Q value of the rubber-modified thermoplastic resin (A) can be adjusted by selecting the type of chain transfer agent, initiator, etc. used during polymerization.
A method of appropriately selecting the amount, a method of appropriately selecting the polymerization temperature,
It can be carried out by appropriately selecting the gel content and the molecular weight of the rubbery polymer as the component (a). Examples of the method for producing the rubber-modified thermoplastic resin (A) include a solution polymerization method, a bulk polymerization method, a suspension polymerization method, an emulsion polymerization method, and a combination of these methods. A preferable polymerization method is an emulsion polymerization method, and as the polymerization aid used in the emulsion polymerization method, a generally known one can be used.

As the polymerization initiator used in the production of the rubber-modified thermoplastic resin (A) of the present invention, there are various organic peroxides such as hydroperoxide, alkyl perester and percarbonate, and cumene hydroper is preferable. Oxide, diisopropylbenzene hydroperoxide and t-butylperoxyisopropyl carbonate. Particularly, when t-butyl peroxyisopropyl carbonate is used, the effect of the present invention which is more excellent can be obtained. The preferred amount of the above initiator is 0.1 to 100 parts by weight of the total of the rubber component and the monomer component.
2 parts by weight. Examples of the chain transfer agent include halogenated hydrocarbons (eg, chloroform, bromoform, etc.), mercaptans (eg, n-dodecylmercaptan, t-dodecylmercaptan, n-octylmercaptan, n-hexadecylmercaptan, etc.), terpenes. (Eg, dipentene, terpinolene, etc.) and α-methylstyrene dimer. The other thermoplastic resin (B) according to claim 2 mixed with the rubber-modified thermoplastic resin (A) is, for example, ABS resin / AES resin / AAS resin having a rubber-like polymer content of less than 50% by weight. Styrene resins such as AS resin, HIPS and PS; Olefin resins such as polyethylene and polypropylene; PA6
Polyamide resins such as PA66, PA46 and PA12; Polyester resins such as polybutylene terephthalate, polyethylene terephthalate and polyarylate; Polyphenylene ether resins such as polycarbonate resin, polyphenylene ether or polyphenylene ether / styrene resin; polyacetal, vinyl chloride resin, polysulfone , PPS, polyether sulfone, ethylene-vinyl acetate copolymer, EVOH and the like, and these can be used alone or in combination of two or more. Preferred other thermoplastic resins (B) are as follows.
Each of a. and b. may be used alone or in combination of a. and b. a .; in the presence of a rubbery polymer, at least two kinds of monomers selected from the group consisting of aromatic compounds, vinyl cyanide compounds, (meth) acrylic acid esters, and maleimide monomers are used. A rubber-modified thermoplastic resin obtained by polymerization and having a rubbery polymer content of less than 50% by weight. The rubber-like polymer and the monomer here include those shown above. The intrinsic viscosity (30 ° C. in methyl ethyl ketone) of the rubber-modified thermoplastic resin soluble in methyl ethyl ketone is preferably 0.2 to 1 dl / g, and more preferably 0.3 to 0.6 dl / g. b .: Obtained by polymerizing a monomer consisting of at least two groups selected from the group consisting of aromatic vinyl compounds, vinyl cyanide compounds, (meth) acrylic acid esters, and maleimide-based monomers, and unique The viscosity (measured at 30 ° C. using methyl ethyl ketone as a solvent) is preferably 0.2 to 1.3 dl /
g, more preferably 0.3 to 1.0 dl / g, and particularly preferably 0.35 to 0.7 dl / g. Examples of the above a. Are, for example, ABS resin, AES resin, AA
Examples thereof include S resin and MBS resin, and among them, ABS resin and AES resin are preferable. As for b. Above,
The following copolymers may be mentioned. I. Copolymer of aromatic vinyl compound and vinyl cyanide compound. The preferable composition ratio is 50 to 99 for the former monomer.
Polymerization%, the latter is 1 to 50% by weight. B. Copolymer of aromatic vinyl compound and (meth) acrylic acid ester. C. Aromatic vinyl compound and maleimide-based monomer and, if necessary, vinyl cyanide compound and / or (meth)
Copolymer consisting of acrylic acid ester, in place of the above maleimide-based monomer, using an unsaturated acid anhydride monomer, imidization of the resulting copolymer, the resulting post-imide type of Copolymers are also included here. The aromatic vinyl compound, vinyl cyanide compound, (meth) acrylic acid ester, and maleimide-based monomer here are the same as those shown above.

The rubber-modified thermoplastic resin (A) may be replaced with the rubber-modified thermoplastic resin (A) instead of the thermoplastic resin composition (A) and the other thermoplastic resin (B). Each component is appropriately blended so that the rubbery polymer as the component (a) of A) is contained in the composition preferably in an amount of 3 to 35% by weight. The more preferable content of the component (a) is 5 to 25% by weight. If the content of the component (a) is less than 3% by weight, sufficient impact strength cannot be obtained. On the other hand, if it exceeds 35% by weight, the molded product becomes soft, which is not preferable. When a rubber-modified thermoplastic resin (C) other than the rubber-modified thermoplastic resin (A) of the present application is used as the other thermoplastic resin (B), the rubber contained in the rubber-modified thermoplastic resin (C) The polymer (hereinafter referred to as “a ′ component”) is handled as follows. a'component is also a
It is regarded as an ingredient and the following conditions are to be met. (A +
a ') content is 3-35 wt% and a content is 3-
35% by weight. Preferably, the content of (a + a ') is 5 to 25% by weight and the content of a is 5 to 25% by weight.

The thermoplastic resin composition according to claim 2 of the present invention is a rubber-modified thermoplastic resin (A) and a thermoplastic resin (B).
And, if necessary, various additives are kneaded and produced. As a kneading method, there is a method using an extruder, a roll, a Banbury mixer, a kneader or the like. A preferable method is a method using an extruder, and examples of the extruder include a single-screw extruder and a twin-screw extruder. When kneading various components using the above kneading method, all the components may be kneaded together, or some of the components may be kneaded first, and the remaining components may be added together or separately. You may knead. Further, various additives can be added to the rubber-modified thermoplastic resin (A), if necessary. When kneading is required, the kneading can be performed by the method described above. As various additives, known colorants, pigments,
Lubricants, weathering agents, antistatic agents, antioxidants, flame retardants, heat aging inhibitors, plasticizers, antibacterial / antifungal agents and the like can be mentioned.
The thermoplastic resin composition according to claim 2 of the present invention is injection molded,
Various molded articles can be molded by sheet extrusion, vacuum molding, profile extrusion, injection press, foam molding, blow molding, blow molding and the like.

[0011]

EXAMPLES The present invention will be described in more detail below with reference to examples. In the examples, parts and% are based on weight unless otherwise specified. Further, various evaluations in the examples are values measured as follows. [Evaluation Method] (1) Measurement of Q Value The resin used for the measurement had a volatile substance content adjusted to 0.1 wt% or less under the condition of 110 ° C. × 60 minutes. Q value measurement conditions Measuring device: Shimadzu flow tester CAPILLARY R
HEOMETER CFT-500 Measurement conditions: Sample amount: 1.8 g Plunger area: 1.0 cm ² Die size: 2.0 mm length x 1.0 mmφ Preheating temperature and time: 200 ° C x 5 minutes Measurement temperature: 200 ° C Load Weight: 60 kg / cm ² (2) Rubber-modified thermoplastic resin (A) and thermoplastic resin
Mixing method of (B) The rubber-modified thermoplastic resin (A), the thermoplastic resin (B) and the additive are mixed in a ratio shown in Table 2 using a Henschel mixer, and the mixture is extruded at a cylinder set temperature of 200 ° C. The pellets were obtained by the machine. (3) Method for molding test piece Using the pellet obtained by the method (2) as a molding material, a test piece for measuring gloss and a test piece for measuring Izod impact strength were molded under the following molding conditions. Molding machine: 5 oz In-line screw type molding machine Mold temperature: 50 ° C. ± 5 ° C. Molding machine setting conditions: Cylinder set temperature: 200 ° C. Injection pressure: Primary pressure 75-95 kg / cm ² ,
Secondary pressure 50 kg / cm ² Back pressure: 5 kg / cm ² Molding cycle: Injection 15 seconds, loading 10 seconds, curing 40 seconds, cycle start 2 seconds (4) Gloss measurement Digital gonio-gloss meter (Suga tester DGITA product
L VARIABLEGROSS METER UGV
-5D) was used to measure the incident angle and the acceptance angle at 45 ° C. (5) Measurement of Izod impact strength ASTM D256 (1/4 ", with notch, unit = kg
-Cm / cm). (6) Method for measuring fisheye A sheet sample for fisheye measurement was prepared and the fisheye was measured by the following method. A 50 ton press machine heated to 220 ° C. is prepared. The pellet obtained by the above method (2) is sandwiched between SUS mold plates (30 × 30 cm × 0.5 mm). (10
〜15g) Scissors directly into the press machine, 0-0.5kg / cm
Apply pressure of ² and warm for 5 minutes. Apply pressure slowly (up to 10 kg / cm ² )
Slowly pull out the pellet sample (melt) protruding from between the mold plates. Draw out the sample into a film and have a thickness of about 10-3
With a thickness of 0 μm, pull out more than 1 m. A circle with a diameter of 3.57 cm (area 10 cm ² ) is drawn on the film sample, and the fish eyes in the circle are counted.
(Diameter of 0.2 mm or more) is performed three times, and the total is divided by the area to obtain the number per 1 cm ² , and the fisheye is evaluated. [Reference Example 1. Manufacturing Method of Rubber-Modified Thermoplastic Resin (A)] In a flask, 60 parts of polybutadiene rubber latex in terms of solid content and 10 parts of styrene-butadiene copolymer rubber latex in terms of solid content were added, and ion-exchanged water was added to 150
Parts, styrene 7 parts, acrylonitrile 3 parts, and t-dodecyl mercaptan 0.2 parts were further added to raise the temperature in the flask to 60 ° C., and then sodium pyrophosphate 0.2
Parts, 0.01 parts of ferrous sulfate heptahydrate, 0.4 parts of glucose dissolved in 20 parts of ion-exchanged water, and 0.1 part of cumene hydroperoxide was further added to start polymerization, The warm bath temperature was kept at 70 ° C. After polymerizing for 1 hour, 21 parts of styrene, 9 parts of acrylonitrile, 0.5 part of t-dodecyl mercaptan and 0.2 part of cumene hydroperoxide were continuously added over 2 hours, and further 1 part was added.
Polymerization was carried out for a period of time to complete the reaction. The obtained copolymer latex was coagulated with sulfuric acid, washed with water and dried. Table 1
ABS-1 shown in 1 was obtained.

[0012]

[Table 1]

In Table 1, ABS-2 and ABS-4 are A
Polymerization was carried out under the same conditions as ABS-1 and ABS-3, except that t-butylperoxyisopropyl carbonate was used instead of cumene hydroperoxide of BS-1 and ABS-3. ABS-3, 5 in Table 1,
Nos. 6, 7, and 8 were ABS-1 formulations, and the amounts of rubber and t-dodecyl mercaptan were appropriately changed, and the other conditions were the same as those of ABS-1. (Thermoplastic resin) AS-1; a copolymer of 75% styrene and 25% acrylonitrile, and [η] (inherent viscosity of methyl ethyl ketone bath content) is 0.4 dl / g AS-2; 75% styrene and acrylonitrile. 25% copolymer, [η] is 0.6 dl / g AS-3; 70% styrene, 30% acrylonitrile, [η] is 0.7 dl / g Examples 1 to 9 Comparative Examples 1 to 3 Examples 1 to 9 are thermoplastic resin compositions using a rubber-modified thermoplastic resin having a Q value within the range of the present invention. Table 2 shows the formulation and evaluation results.

[0014]

[Table 2]

Comparative Examples 1 to 3 are thermoplastic resin compositions using a rubber-modified thermoplastic resin having a Q value outside the range of the present invention. Table 2 shows the formulation and the evaluation results. As is clear from comparison with Comparative Examples 1 to 3, Examples 1 to 9 have excellent gloss and impact resistance of the molded product, and the defective phenomenon of fisheye generation is also improved.

[0016]

The rubber-modified thermoplastic resin (A) of the present invention
Is another thermoplastic resin (B) even if it has a high rubber component content.
The molded product obtained by blending with is excellent in gloss and impact resistance,
Moreover, the defective phenomenon of fisheye generation has been greatly improved. Further, since the content of the rubber component is high, the effect of improving the impact resistance can be obtained with a small amount, so that the developability can be easily accommodated.
Moreover, since a thermoplastic resin such as an AS resin has excellent productivity and low cost, it is possible to mass-produce an ABS resin having excellent productivity and low cost by blending it with the thermoplastic resin.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroo Nakamura 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (2)

[Claims] 1. A polymer obtained by polymerizing an aromatic vinyl compound (b) and a vinyl cyanide compound (c) in the presence of a rubbery polymer (a) component, wherein the content of the (a) component is from 50 to 50.
80% by weight, the content of the component (b) is 5 to 48% by weight,
The component (c) is 2 to 45% by weight, and the Q value defined in the text is 3
A rubber-modified thermoplastic resin characterized by having a graft ratio of 0 × 10 ⁻⁴ to 50 × 10 ⁻³ cc / sec and 5% by weight or more. 2. A composition comprising the rubber-modified thermoplastic resin (A) according to claim 1 and another thermoplastic resin (B), wherein the content of the component (a) in the composition is 3 to 35. A thermoplastic resin composition, which is wt%.