JPH05279549A - Flame-retardant thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To improve the chemical resistance by incorporating an aromatic vinyl/conjugated diene block copolymer and a halogenated polyolefin into a flame-retardant thermoplastic resin composition composed mainly of an ABS resin and an AS resin. CONSTITUTION:10-100wt.% rubber-toughened styrene resin obtained by polymerizing an aromatic vinyl and vinyl cyanide in the presence of a rubbery polymer is mixed with 90-0wt.% aromatic vinyl/vinyl cyanide copolymer. 100 pts.wt. of the obtained mixture is mixed with 0.5-20 pts.wt. aromatic vinyl/conjugated diene block copolymer (e.g. styrene/butadiene block copolymer) and/or derivative thereof, 0.5-20 pts.wt. halogenated polyolefin (e.g. chlorinated polyethylene), 0-50 pts.wt. flame retardant (e.g. tetrabromobisphenol A) and 0-15 pts.wt. antimony compound (e.g. antimony trioxide).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition having improved chemical stress cracking resistance without lowering surface gloss.

[0002]

BACKGROUND OF THE INVENTION Flame-retardant resins are widely used as molding materials for housing parts of electric products. Since an electric wire covered with a covering material containing a plasticizer is used for an electric product, the plasticizer causes a trouble due to lack of chemical stress cracking in which a housing or a molding material is damaged. However, conventional flame-retardant resins are not sufficient in chemical stress cracking resistance, and improvement thereof has been demanded. For flame-retardant ABS resin, A
A method of increasing the vinyl cyanide content in the BS resin is generally used, and the chemical stress cracking resistance is improved by this method, but it has not been sufficient yet.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and provides a flame-retardant resin composition excellent in chemical stress cracking resistance without lowering surface gloss. The purpose is to provide.

[0004]

The present invention relates to (A) 10 to 100% by weight of a rubber-reinforced styrenic resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of a rubbery polymer, and (B) ) A (C) aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product, based on 100 parts by weight of a mixture consisting of 0 to 90% by weight of a copolymer of aromatic vinyl and vinyl cyanide. : 0.5 to 20 parts by weight (D) halogenated polyolefin: 1 to 40 parts by weight (E) flame retardant: 0 to 50 parts by weight (F) antimony compound: 0 to 15 parts by weight Flame-retardant thermoplastic resin composition, and (A) 10 to 100% by weight of a rubber-reinforced styrene resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of a rubber-like polymer, and (B) (C ') 0.5 to 20 parts by weight of an aromatic vinyl-conjugated diene-based block copolymer shown below per 100 parts by weight of a mixture of 0 to 90% by weight of a copolymer of aromatic vinyl and vinyl cyanide. Parts (E) Flame retardant: 0 to 50 parts by weight (F) Antimony compound: 0 to 15 parts by weight Flame-retardant thermoplastic resin composition Note that the component (C ') is an aromatic compound. Vinyl compound content is 25 ~
95% by weight of an aromatic vinyl compound-conjugated diene block copolymer, which is represented by the following general formula. (AB) n and / or ABAA and / or (AB) nX (wherein A is an aromatic vinyl compound polymer block, and the total amount of A at both ends is aromatic vinyl compound). 50 for all compounds
To 97% by weight, B is a copolymer of a conjugated diene and an aromatic vinyl compound, has 2 to 10 tapered blocks in which the aromatic vinyl compound gradually increases, and n is an integer of 3 to 6, X is the residue of the coupling agent. ) Is provided.

The present invention will be described in detail below.
Examples of the rubber-like polymer used as the component (A) include a diene rubber-like polymer represented by polybutadiene, a butadiene-styrene random copolymer, polyisoprene, a styrene-butadiene block copolymer, or a hydrogen thereof. Although additives, ethylene-propylene-diene copolymer, acrylic rubber mainly composed of acrylic acid ester, isobutylene-isopropylene copolymer, silicone rubber, polyurethane rubber and the like can be used,
In order to easily obtain a desired graft ratio, it is preferable to use a diene rubber polymer such as polybutadiene or butadiene-styrene copolymer, and to improve light resistance, silicone rubber or ethylene-propylene copolymer is used. It is preferable to use a hydrogenated product of an ethylene-α-olefin rubbery polymer such as a polymer, an ethylene-propylene-non-conjugated diene copolymer, an ethylene-butene copolymer, or a diene rubbery polymer.

Examples of the aromatic vinyl compound used as the component (A) include styrene, α-methylstyrene, p
-Methyl styrene, vinyltoluene and chlorostyrene, halogen-substituted styrenes such as bromostyrene, and the like are mentioned, and styrene and α-methylstyrene are preferable.

Examples of the vinyl cyanide compound include acrylonitrile and methacrylonitrile.

The ratio of the (co) polymerized aromatic vinyl compound and vinyl cyanide compound which are components other than the rubbery polymer in the rubber-reinforced styrene resin as the component (A) is preferably 50 to 50. 97/50 to 3% by weight, more preferably 60 to 95/40 to 5% by weight. A vinyl cyanide compound content of more than 50% by weight is not preferable because the thermal stability is lowered. If the vinyl cyanide compound content is less than 3% by weight, impact resistance and chemical resistance are poor.

Examples of other monomers other than those mentioned above which can be used in combination as required include, for example, (meth) acrylic acid esters such as methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate; acrylic acid, (Meth) acrylic acid such as methacrylic acid; maleimide-based monomers such as maleimide and N-phenylmaleimide; non-conjugated divinyl compounds represented by divinylbenzene, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, and other polyvalent compounds One kind or two or more kinds of (meth) acrylate compounds can be appropriately used within a range that does not affect the polymerization step and the physical properties of the composition of the present invention. The amount of these other monomers used is preferably 50% by weight or less, more preferably 30% by weight or less in the monomer mixture.

The content of the rubbery polymer component (A) is preferably 3 to 60% by weight, more preferably 5 to 40% by weight. If the content is less than 3% by weight, sufficient impact resistance cannot be obtained, which is not preferable. On the other hand, if it exceeds 60% by weight, flame retardancy and practical moldability are deteriorated, which is not preferable.

The graft ratio in the component (A) is preferably 15 to 180% by weight, more preferably 30 to 150.
If the graft ratio is less than 15% by weight in terms of weight%, sufficient impact resistance cannot be obtained, which is not preferable. On the other hand, if it exceeds 180% by weight, the glossiness of the molded article tends to decrease and the heat resistance tends to decrease, such being undesirable.

Further, the intrinsic viscosity of the methyl ethyl ketone soluble component in the component (A) is preferably 0.3 to 0.8 dl /
g, and more preferably 0.35 to 0.7 dl / g. Within this range, a flame-retardant resin composition having a good balance between impact resistance and practical moldability can be obtained. The weight average molecular weight of the methyl ethyl ketone soluble component in the component (A) used in the present invention is 10,000 to 800,000, preferably 50,000 to 500,000. Is not expected, and if it is larger than this range, the compatibility with the components (A) to (B) deteriorates, which is not preferable.

As the method for producing the component (A), known emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization or the like may be used. At this time, the intrinsic viscosity of the methyl ethyl ketone soluble component can be adjusted by appropriately selecting the type and amount of the molecular weight modifier at the time of polymerization. The graft ratio can be adjusted by appropriately selecting the kind and amount of the molecular weight modifier, and the addition time of the monomer component (monomer mixture) to the polymerization system.

The component (B) is a copolymer of aromatic vinyl and vinyl cyanide, which is a styrene resin.
As the aromatic vinyl compound which is (co) polymerized with the component (B), the aromatic vinyl compounds shown above can be used. Preferred are styrene and α-methylstyrene.
The copolymerized vinyl cyanide compound may, for example, be acrylonitrile or methacrytonitrile.

The proportion of the aromatic vinyl compound and the vinyl cyanide compound copolymerized with the component (B) is preferably 50 to 100/50 to 0% by weight, more preferably 60 to 95/40 to 5%. % By weight. If the amount of the vinyl cyanide compound exceeds 50% by weight, the thermal stability is lowered, which is not preferable. When a vinyl cyanide compound is used, the miscibility with the component (A) is further improved, and a composition of excellent quality can be obtained. Other copolymerizable monomers can be used if necessary. As the other copolymerizable monomer, the other copolymerizable monomer described above can be used.
The intrinsic viscosity of the component (B) is preferably 0.3-0.
8 dl / g, more preferably 0.35 to 0.7 dl /
It is g. Within this range, a flame-retardant resin composition having a good balance between impact resistance and practical moldability can be obtained. (B)
As the method for producing the components, known emulsion polymerization, suspension polymerization,
Polymerization may be performed by solution polymerization, bulk polymerization, or the like. In addition,
The component (B) is added to adjust the content of the rubber-like polymer in the mixture of the component (A) and the component (B).

The component (C) is an aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product. The block copolymer of the component (C) used in the composition of claim (1) is not particularly limited, but preferably the following aromatic vinyl compound-conjugated diene block copolymer or its It is a hydrogenated product. (A
-B) n and / or A-B-A and / or (A
-B) n X (In the formula, A is a polymer block of an aromatic vinyl compound, and preferably contains 50% by weight or more, and more preferably 50 to 97% by weight of the total aromatic vinyl compound. B is a conjugated diene or a copolymer block of a conjugated diene in which 50% by weight or less of an aromatic vinyl compound is copolymerized in B, and the total amount of A is 50 to 100% by weight of the total aromatic vinyl compound. , X is a residue of the coupling agent, and n is an integer of 2 to 6, preferably 3 to 6.) The content of the wholly aromatic vinyl compound in the block copolymer is 25 to 95% by weight, preferably 28 to 95% by weight. 90% by weight
Is.

As the aromatic vinyl compound constituting the block copolymer, those shown above can be used. Of these, styrene is particularly preferred. On the other hand, examples of the conjugated diene compound include butadiene, isoprene, and piperylene. Of these, preferred are butadiene and isoprene. Further, claim (2)
The block copolymer of the component (C ') used in the composition (1) can also be used, and the use of the component (C') is preferable because a composition having more excellent chemical stress cracking resistance can be obtained.

The amount of the component (C) added is 0.5 with respect to 100 parts by weight of the mixture of the components (A) and (B).
-20 parts by weight, preferably 3-10 parts by weight. If the amount added is less than 0.5 part by weight, the desired chemical stress cracking resistance cannot be obtained, while if it exceeds 20 parts by weight, flame retardancy and surface gloss are significantly reduced, which is not preferable.

The component (D) is a halogenated polyolefin, and examples thereof include chlorinated polyethylene, chlorinated polypropylene, brominated polyethylene, and chlorinated ethylene-propylene copolymer. Among these, chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, particularly chlorinated polyethylene, are preferable. The halogen content in these halogenated polyolefins is preferably 20 to 50% by weight, more preferably 25 to 4%.
It is 5% by weight. By using the component (D), flame retardancy and light resistance can be improved.

The weight average molecular weight of the halogenated polyolefin used in the present invention is preferably 100,000 to.
300,000, more preferably 150,000 to 25
It is 10,000. If the weight molecular weight is less than 100,000, sufficient resistance to chemical stress cracking cannot be obtained. 3
If it exceeds 0,000, the practical formability is deteriorated, which is not preferable. Further, the addition amount of the component (D) is 0.5 with respect to 100 parts by weight of the mixture composed of the components (A) and (B).
-20 parts by weight, preferably 3-10 parts by weight. If the addition amount is less than 0.5 parts by weight, the desired chemical stress cracking resistance cannot be obtained, while if it exceeds 20 parts by weight, practical moldability and molding heat stability are significantly reduced, which is not preferable.

The component (E) is a flame retardant and is mainly a halogenated organic compound. Examples thereof include tetrabromobisphenol A and tetrabromobisphenol S, and tetrabromobisphenol A is preferable.
The amount of component (E) added is 0 to 50 parts by weight, preferably 1 to 45 parts by weight, more preferably 5 to 40 parts by weight, relative to 100 parts by weight of the mixture consisting of components (A) and (B). It is particularly preferably 15 to 30 parts by weight. If the amount added exceeds 50 parts by weight, the molding thermal stability will be significantly reduced, which is not preferable.

The component (F) is an antimony compound,
Examples thereof include antimony trioxide, antimony tetraoxide, antimony pentoxide, sodium antimonate, and antimony phosphate, with antimony trioxide and sodium antimonate being preferred. When the component (F) is used,
Excellent flame retardancy is obtained in general. If the added amount of the component (F) exceeds 15 parts by weight with respect to 100 parts by weight of the mixture of the components (A) and (B), the impact resistance is significantly lowered, which is not preferable.

The components (A) and (B) of claim (2) are the same as those of claim (1). That is, the component (A) is a rubber-reinforced styrene resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of a rubbery polymer, and the component (B) is aromatic vinyl and vinyl cyanide. Is a copolymer consisting of (A) component 10 to 100% by weight
With respect to 100 parts by weight of a mixture consisting of 90 to 0% by weight of the component (B) and the component (C), the block copolymer and hydrogenated product thereof shown below are used as the component (C '). When the component (C ') is used, a composition having excellent resistance to chemical stress cracking can be obtained.

The component (C ') is a block copolymer having an aromatic vinyl compound content of 25 to 95% by weight, and has the general formula (AB) n and / or ABA and / or (AB) n X (wherein A is an aromatic vinyl compound monomer block, the total amount of A comprises 50 to 97% by weight of the aromatic vinyl compound, and B is a conjugated diene and an aromatic vinyl compound. A copolymer with a vinyl compound, B having 2 to 10 tapered blocks in which an aromatic vinyl compound gradually increases, n is an integer of 3 to 6,
X is a residue of a coupling agent) and is a block copolymer. In B in the above formula, the content of the aromatic vinyl compound constituting the chain in which one or four or less of the aromatic vinyl compound is a monomer unit is preferably 1 to 25% by weight of the whole aromatic vinyl compound, More preferably 2
-20% by weight, particularly preferably 5-20% by weight.
The composition ratio of the aromatic vinyl compound and the conjugated diene in B is preferably 3 to 15/97 to 85% by weight. Within this range, the chemical stress cracking resistance is excellent. On the other hand, the preferable number of tapered blocks is 2 to 7.
As the above aromatic vinyl compound, the aromatic vinyl compounds shown above can be used. Preferred is styrene. As the conjugated diene, those shown above can be used. Preferred are butadiene and isoprene.

The component (C ') can be produced, for example, by the following method. That is, an ether or a tertiary amine is added to a hydrocarbon solvent, an organic lithium compound is used as an initiator, an aromatic vinyl compound is first polymerized, and after the polymerization reaction is substantially completed, an aromatic vinyl compound is obtained. The mixture of the conjugated diene compound is added in two to ten times and polymerized, and if necessary, after that, the same amount of conjugated diene as one addition is added and polymerization is performed.

Further, the block copolymer of the general formula ABA can be obtained by subsequently polymerizing an aromatic vinyl compound. The block copolymer of the general formula (AB) n X is
After that, the coupling reaction is carried out using a conventionally known coupling agent such as tetrachlorosilane. The (AB) n type block copolymer may be prepared by first adding the conjugated diene and the aromatic vinyl compound at the same time in the production of the ABAA type. Further, in the production of the ABA type block copolymer, it is sufficient that the last aromatic vinyl compound is not polymerized. In the step of polymerizing the mixture of the aromatic vinyl compound and the conjugated diene in 2 to 10 times, it is preferable that the amount of the monomer used in each time is approximately the same, and as a method for adding the monomer, Alternatively, the method of adding the monomer mixture or the conjugated diene and the aromatic vinyl compound may be added separately at the same time.

The preferred amount of chain distribution of the aromatic vinyl compound in the block copolymer is 0.0 or 100 parts by weight of the ether or tertiary amine in the hydrocarbon solvent.
It is obtained by adding 05 to 5 parts by weight, preferably 0.005 to 0.5 parts by weight.

As the hydrocarbon solvent used for producing the block copolymer used in the present invention, cyclopentadiene, cyclohexane, benzene, xylene and mixtures thereof with pentahexane, heptane, butane and the like are used. Further, as the organic lithium compound, n-
Butyl lithium, sec-butyl lithium, tert-
Butyl lithium, n-hexyl lithium, iso-hexyl lithium, phenyl lithium, naphthyl lithium and the like are used.

The amount of the component (C ') added is 0.5 with respect to 100 parts by weight of the mixture of the components (A) and (B).
-20 parts by weight, preferably 3-10 parts by weight. If the amount added is less than 0.5 part by weight, the desired chemical stress cracking resistance cannot be obtained, while if it exceeds 20 parts by weight, flame retardancy and surface gloss are significantly reduced, which is not preferable. The component (E) and the component (F) of claim (2) are the same in the compounding amounts as in claim (1).

The flame-retardant resin composition of the present invention can be produced without any change from the known method for producing a resin composition. That is, the above components and other necessary additives can be produced by a commonly used Henschel mixer, mixing with a tumbler, etc., and melt mixing with a hot roll, an extruder, a Banbury mixer, etc. It is also possible to prepare a masterbatch with a high concentration of some of the components in advance, and mix this with an unblended component, which is a so-called masterbatch system.

The flame-retardant resin composition of the present invention is subsequently molded by extrusion molding, injection molding, compression molding or the like to obtain a molded article. These molded articles have mechanical properties as well as
It is excellent in flame retardancy, chemical stress cracking resistance, practical formability and impact resistance, and has a good surface appearance, so it is extremely useful as mechanical parts, electric parts and automobile parts.

[0032]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The parts and% in the examples are based on weight. The evaluation of the physical properties of the obtained composition is as follows. Chemical resistance To measure chemical stress cracking resistance, thickness 4
A test piece having a width of 0 mm and a width of 1.6 mm was fixed on a jig having a 1/4 ellipse, a plasticizer was applied thereto, and a critical strain was obtained and evaluated by a position of a crack generated after 48 hours. Combustion test According to UL95. Specimen; 1/8 "x 1/2" x 5 "and 1/12" x
½ ″ × 5 ″ surface gloss The glossiness (%) was measured by irradiating the sample with a light source at an incident angle of 45 ° using a gloss meter.

(A) Preparation of Graft Copolymer: Emulsion polymerization was carried out in the presence of polybutadiene latex using styrene, acrylonitrile and a polymerization chemical to obtain the graft copolymer shown in Table 1.

[Table 1] (B) Preparation of copolymer: Styrene, acrylonitrile and a polymerization chemical were used to obtain a copolymer of Table 2 by bulk polymerization.

[Table 2] (C) Preparation of block copolymer: Styrene, butadiene and an organolithium compound were used to obtain a block copolymer of Table 3 by bulk polymerization.

[Table 3] Preparation of component (D): As component (D), Daiso rack H135 (chlorine content 35%, weight average molecular weight 200,000) manufactured by Daiso Co., Ltd. was used. Preparation of component (E): Tetrabromobisphenol A (TBA) was used as the component (E). Preparation of component (F): Antimony trioxide was used as the component (F).

Examples 1 to 7 and Comparative Examples 1 to 4 The formulations shown in Table 4 were mixed using a Henschel mixer and melt-kneaded with a 50 mmφ single screw extruder to prepare pellets. Various physical properties were evaluated by using. The results are also shown in Table 4.

[Table 4]

Examples 1 to 9 are flame-retardant resin compositions of the present invention, and the objects of the present invention can be obtained. On the other hand, Comparative Example 1 is a block copolymer of the component (C),
In the case where neither the halogenated polyolefin as the component (D) was added, the chemical resistance was poor. In addition, Comparative Example 2 is a component (C),
This is an example without addition, and the chemical resistance is also inferior. In Comparative Example 3 in which only the component (D) was added over the range, the surface glossiness was poor. Comparative Example 4 is an example in which the component (C) is added in excess of the range and the component (D) is not added, and the flame retardancy and surface gloss are inferior. Comparative Example 5 is an example in which both the component (C) and the component (D) were added in excess of the range, and the flame retardancy and surface gloss were inferior.

[0036]

The flame-retardant resin composition of the present invention contains an aromatic vinyl-conjugated diene block copolymer and a chlorinated polyolefin compound, so that chemical stress resistance can be achieved without reducing surface gloss and practical moldability. The cracking property is significantly improved.

Since the conventional flame-retardant resin composition has poor chemical resistance, it has been a great obstacle to the development of new applications, but the flame-retardant resin composition of the present invention has excellent chemical resistance. Therefore, it can be expected to expand to new uses. Therefore, its industrial value is great.

[Procedure amendment]

[Submission date] May 20, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

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[Correction method] Change

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[0004]

The present invention relates to (A) 10 to 100% by weight of a rubber-reinforced styrenic resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of a rubbery polymer, and (B) ) A (C) aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product, based on 100 parts by weight of a mixture consisting of 0 to 90% by weight of a copolymer of aromatic vinyl and vinyl cyanide. : 0.5 to 20 parts by weight (D) Halogenated polyolefin: 0.5 to 20 parts by weight (E) Flame retardant: 0 to 50 parts by weight (F) Antimony compound: 0 to 15 parts by weight A flame-retardant thermoplastic resin composition, and (A) 10 to 100% by weight of a rubber-reinforced styrene resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of a rubber-like polymer; (B) 100 parts by weight of a mixture of 0 to 90% by weight of a copolymer of aromatic vinyl and vinyl cyanide, (C ') 0.5 of an aromatic vinyl conjugated diene block copolymer shown below. To 20 parts by weight (E) flame retardant: 0 to 50 parts by weight (F) antimony compound: 0 to 15 parts by weight Flame-retardant thermoplastic resin composition The above component (C ') is , Aromatic vinyl compound content is 25 ~
95% by weight of an aromatic vinyl compound-conjugated diene block copolymer, which is represented by the following general formula. (AB) n and / or ABAA and / or (AB) nX (wherein A is an aromatic vinyl compound polymer block, and the total amount of A at both ends is aromatic vinyl compound). 50 for all compounds
To 97% by weight, B is a copolymer of a conjugated diene and an aromatic vinyl compound, has 2 to 10 tapered blocks in which the aromatic vinyl compound gradually increases, and n is an integer of 3 to 6, X is the residue of the coupling agent. ) Is provided.

[Procedure Amendment 2]

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[Correction method] Change

[Correction content]

The component (D) is a halogenated polyolefin, and examples thereof include chlorinated polyethylene, chlorinated polypropylene, brominated polyethylene, and chlorinated ethylene-propylene copolymer. Among these, chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, particularly chlorinated polyethylene, are preferable. The halogen content in these halogenated polyolefins is preferably 20 to 50% by weight, more preferably 25 to 4%.
It is 5% by weight. By using the component (D),
Improves flame retardancy compared to using (E) component alone
And, like the component (C), drug-resistant stress
The racking property can be improved.

[Procedure 3]

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[Correction method] Change

[Correction content]

The weight average molecular weight of the halogenated polyolefin used in the present invention is preferably 100,000 to.
300,000, more preferably 150,000 to 25
It is 10,000. If the weight molecular weight is less than 100,000, sufficient resistance to chemical stress cracking cannot be obtained. 3
If it exceeds 0,000, the practical formability is deteriorated, which is not preferable. Further, the addition amount of the component (D) is 0.5 with respect to 100 parts by weight of the mixture composed of the components (A) and (B).
-20 parts by weight, preferably 3-10 parts by weight. If the addition amount is less than 0.5 part by weight, the desired chemical stress cracking resistance cannot be obtained, while if it exceeds 20 parts by weight , the chemical stress cracking resistance is improved, but the practical moldability and molding heat stability are improved . Is significantly reduced, which is not preferable.

[Procedure amendment 4]

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[0021] Component (E) is a flame retardant, mainly halogenated organic compound is not particularly limited, for example, tetrabromobisphenol A, Ru is like tetrabromobisphenol S. The amount of component (E) added is 0 to 50 parts by weight, preferably 1 to 45 parts by weight, more preferably 5 to 40 parts by weight, relative to 100 parts by weight of the mixture consisting of components (A) and (B). It is particularly preferably 15 to 30 parts by weight. If the amount added exceeds 50 parts by weight, the molding thermal stability will be significantly reduced, which is not preferable.

[Procedure Amendment 5]

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[Correction method] Change

[Correction content]

The component (C ') is a block copolymer having an aromatic vinyl compound content of 25 to 95% by weight, and has the general formula (AB) n and / or ABA and / or (AB) n X (wherein A is an aromatic vinyl compound monomer block, the total amount of A comprises 50 to 97% by weight of the aromatic vinyl compound, and B is a conjugated diene and an aromatic vinyl compound. A copolymer with a vinyl compound, B having 2 to 10 tapered blocks in which an aromatic vinyl compound gradually increases, n is an integer of 3 to 6,
X is a block copolymer you express a residue of a coupling agent). In B in the above formula, the content of the aromatic vinyl compound constituting the chain in which one or four or less of the aromatic vinyl compound is a monomer unit is preferably 1 to 25% by weight of the whole aromatic vinyl compound, It is more preferably 2 to 20% by weight, particularly preferably 5 to 20% by weight. The composition ratio of the aromatic vinyl compound and the conjugated diene in B is preferably 3 to 15/97 to 85% by weight. Within this range, the chemical stress cracking resistance is excellent.
On the other hand, the preferable number of tapered blocks is 2 to 7. As the above aromatic vinyl compound, the aromatic vinyl compounds shown above can be used. Preferred is styrene. As the conjugated diene, those shown above can be used. Preferred are butadiene and isoprene.

[Procedure Amendment 6]

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[Name of item to be corrected] 0032

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[Correction content]

[0032]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The parts and% in the examples are based on weight. The evaluation of the physical properties of the obtained composition is as follows. Chemical resistance To measure chemical stress cracking resistance, width 40
A test piece having a thickness of 1.6 mm and a thickness of 1.6 mm was fixed on a jig having a quarter ellipse, a plasticizer was applied thereto, and a critical strain was obtained and evaluated by the position of a crack generated after 48 hours. It was based on the combustion test UL94 . Specimen; 1/8 "x 1/2" x 5 "and 1/12" x
½ ″ × 5 ″ surface gloss The glossiness (%) was measured by irradiating the sample with a light source at an incident angle of 45 ° using a gloss meter.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C08L 25/12 LDX 9166-4J 51/04 LKY 7142-4J // (C08L 51/04 53:02 (23:28) (72) Inventor Takeki Furuyama 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd.

Claims (2)

[Claims] 1. A rubber-reinforced styrene resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of (A) a rubbery polymer, 10 to 100% by weight, and (B) aromatic vinyl and vinyl cyanide. (C) aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product thereof: 0.5 to 20 parts by weight, relative to 100 parts by weight of a mixture consisting of 0 to 90% by weight of the copolymer consisting of (D) Halogenated polyolefin: 0.5 to 20 parts by weight (E) Flame retardant: 0 to 50 parts by weight (F) Antimony compound: 0 to 15 parts by weight Flame-retardant thermoplastic resin characterized by containing Composition. 2. A rubber-reinforced styrene resin obtained by polymerizing aromatic vinyl and vinyl cyanide in the presence of (A) a rubber-like polymer, 10 to 100% by weight, and (B) aromatic vinyl and vinyl cyanide. (C ') 0.5 to 20 parts by weight of an aromatic vinyl-conjugated diene-based block copolymer shown below (C) to 100 parts by weight of a mixture of 0 to 90% by weight of a copolymer of (E) flame retardant: 0 to 50 parts by weight (F) Antimony compound: 0 to 15 parts by weight, A flame-retardant thermoplastic resin composition comprising: The above component (C ') has an aromatic vinyl compound content of 25 to
95% by weight of an aromatic vinyl compound-conjugated diene block copolymer, which is represented by the following general formula. (AB) n and / or ABAA and / or (AB) nX (wherein A is an aromatic vinyl compound polymer block, and the total amount of A at both ends is aromatic vinyl compound). 50 for all compounds
To 97% by weight, B is a copolymer of a conjugated diene and an aromatic vinyl compound, and has 2 to 10 tapered blocks in which the aromatic vinyl compound gradually increases, and n is 3 to 6
, X is the residue of the coupling agent. )