JPH11181212A - Flame-retardant styrene-based resin composition for molding compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition with excellent heat resistance and impact strength, having such characteristics as heat discoloration-proofness and dripping-proofness, by kneading a specific base resin with an aromatic polyphosphate and others. SOLUTION: This composition is obtained by including (A) a base resin comprising a rubber graft copolymer comprising rubber particles 0.5-10 μm in weight-average size prepared by bulk or solution copolymerization, a second rubber graft copolymer comprising rubber particles 0.05-0.8 μm in weight-average size, and a styrene-based copolymer, a styrene-based resin consisting of a styrene-based copolymer, and a polycarbonate-based resin, (B) an aromatic polyphosphate, (C) a tetrafluoroethylene polymer, and (D) a low-molecular weight maleic anhydride copolymer with a weight-average molecular weight of 800-25,000 made from maleic anhydride and an ethylene based monomer; wherein the rubber content of the component A is 3-40 wt.% based on the total rubber in the component A plus B, and the weight-average size of the rubber particles in this composition as a whole is 0.3-2 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant styrenic resin composition for a molding material, and more particularly to a base resin comprising a styrene-based resin and a polycarbonate-based resin. By kneading ethylene and a maleic anhydride copolymer,
The present invention relates to a styrene-based resin composition that has good heat resistance, prevents high degree of impact strength reduction, improves heat discoloration resistance and prevents dripping, and does not cause a plate-out phenomenon during injection molding. .

[0002]

2. Description of the Related Art Conventionally, a composition comprising a mixture of a styrene resin and a polycarbonate resin can improve disadvantages such as insufficient moldability, impact strength and heat resistance of each resin. Is widely used for products, home appliances, office electrical appliances, and other electrical components. Further, such a composition usually requires flame-retardant properties. Therefore, an attempt is made to achieve a flame-retardant effect by adding an appropriate flame retardant to the composition.

In order to obtain the flame retardant effect, generally, for example, tetrabromobisphenol A (Tetrabromobisphenol A) is used.
Although halogen-based flame retardants such as l-A) are used, the halogen-based flame retardants decompose at the time of molding to produce harmful toxic substances, and thus cause environmental problems such as health hazards and air pollution. In addition, for example, triphenyl phosphat
e), non-halogen flame retardants such as phosphate ester flame retardants such as tricresyl phosphate and diphenylcresyl phosphate can also be used,
Since the melting points of these flame retardants are low, the heat resistance of the molded article is reduced, and the flame retardant is easily transferred to the surface of the molded article at the time of injection molding, thereby causing a so-called "plate out" defect.

[0004]

SUMMARY OF THE INVENTION The present invention provides good heat resistance, high impact strength, prevention of reduction in strength, prevention of thermal discoloration, prevention of dripping, and the like. Another object of the present invention is to provide a flame-retardant styrenic resin composition which does not cause a plate-out phenomenon.

[0005]

Means for Solving the Problems The present inventors have eagerly considered that the above-mentioned drawbacks may occur if a wrong flame retardant is selected when kneading a styrene resin and a polycarbonate resin. As a result of the study, a specific base resin consisting of a styrene-based resin and a polycarbonate-based resin, a predetermined aromatic polyphosphate, polytetrafluoroethylene, and a maleic anhydride copolymer are kneaded to achieve an object. The inventors have found that an effect can be obtained, and have completed the present invention based on such findings.

That is, the present invention relates to (1) (1) 1 to 30 parts by weight of a bulk or solution rubber graft copolymer (A) containing rubber particles having a weight average particle diameter of 0.5 to 10 μm; Styrene resin 2 comprising 1 to 25 parts by weight of an emulsion rubber graft copolymer (B) containing rubber particles having a particle size of 0.05 to 0.8 μm and (3) 0 to 53 parts by weight of a styrene copolymer (C) ~ 55
100 parts by weight of a base resin comprising 45 to 98 parts by weight of a polycarbonate resin (D), 1 to 30 parts by weight of (2) an aromatic polyphosphate (E), and (3) a tetrafluoroethylene polymer (F) a low molecular weight maleic anhydride copolymer (G) composed of 0.02 to 2.0 parts by weight, (4) maleic anhydride having a weight average molecular weight of 800 to 25,000, maleic anhydride of 30 to 65% by weight, and an ethylene monomer. A) a flame-retardant styrenic resin composition for a molding material comprising 0.05 to 5.0 parts by weight, wherein the rubber content of the bulk or solution rubber graft copolymer (A) is in the form of a bulk or solution rubber graft copolymer; (A)
3 to 40% by weight based on the total amount of rubber in the emulsion rubber graft copolymer (B), and the weight average particle size of the rubber particles in the flame-retardant styrene resin composition Diameter
An object of the present invention is to provide a flame-retardant styrenic resin composition for a molding material, wherein the composition is 0.3 to 2 μm.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The rubber used as a raw material of the bulk or solution rubber graft copolymer and emulsion rubber copolymer of the present invention means a polymer having a glass transition temperature of 0 ° C. or lower.

In the present invention, the bulk or solution rubber graft copolymer (A) is 5 to 30 parts by weight of a rubbery polymer,
A total of 100 parts by weight of 95 to 70 parts by weight of the following monomer mixture is reacted by a bulk and / or solution polymerization method. The styrene-based monomer 90-50 in the monomer mixture
Parts by weight, 10 to 50 parts by weight of an acrylonitrile monomer and 0 to 40 parts by weight of a monomer copolymerizable therewith. When the conversion of the polymerization reaction reaches 40 to 95% by weight, the copolymer solution is subjected to a devolatilization treatment to remove unreacted monomers and other volatile components to obtain a rubber having a weight average particle size of 0.5 to 10 μm. A bulk or solution rubber graft copolymer (A) containing particles can be produced.

In the present invention, the bulk or solution rubber graft copolymer (A) is produced using a reactor which continuously performs a bulk or solution polymerization reaction. Examples of the reactor include a plug flow reactor (PRF), a complete mixing type reactor (CSTR), a static mixer type plug flow reactor, and the like. Preferably, a complete mixing type reactor is used. One may be used alone, and preferably two or more may be used in combination. When producing the bulk or solution rubber graft copolymer (A) of the present invention, a polymerization initiator may be added to the reaction system. Examples of the polymerization initiator include acyl peroxide, ester peroxide, ketal peroxide, carbonate peroxide, and an azo compound containing a nitrile group and a cyclohexyl group. The amount of the polymerization initiator to be added is usually 0.01 to 1.0% by weight based on 100 parts by weight of the monomer.

[0010] The reaction temperature of the reactor is controlled at 80 to 200 ° C, more preferably in the range of 90 to 160 ° C. Also,
The pressure in the reactor is controlled between 1 and 5 kg / cm ² , and the time during which the raw material solution stays in the reactor is 1 to 10 hours. For controlling the molecular weight of the polymer, for example, a chain transfer agent such as n-dodecyl mercaptan, t-dodecyl mercaptan, and terpinolene can be used.

After the polymerization step of the polymer is completed, the obtained rubber graft copolymer solution is heated by a preheater,
Unreacted monomers and other volatiles are removed by devolatilization. In general, in the devolatilization treatment, volatile components are removed using a devolatilization device such as a vacuum devolatilization tank or an extruder. And
The volatile matter removed by the condenser is recovered to be a recovered liquid, and the recovered liquid is used as a raw material solution again after removing the contained water as appropriate. The polymer melt from which the volatile components have been removed is extruded and pelletized to obtain pellets of the bulk or solution rubber graft copolymer (A) used in the present invention.

The rubbery polymer used for preparing the bulk or solution graft rubber copolymer (A) used in the present invention is preferably a diene-containing rubber such as butadiene rubber, isoprene rubber, chlorobutadiene rubber, ethylene-propylene. -Ethylidene norbornene rubber, butyl acrylate-dicyclopentenyl acrylate rubber and the like. Butadiene rubbers include types such as high cis (High-Cis) content and low cis (Low-Cis) content. In high cis butadiene rubber, cis (Cis) / vinyl
The typical weight percentage of (Vinyl) is 94-98% / 1-5%, the remaining composition is trans-structure, and the Mooney viscosity is 20-12
0, the molecular weight range is preferably from 100,000 to 800,000. On the other hand, the low cis butadiene rubber preferably has a typical cis / vinyl weight ratio of 20 to 40% / 1 to 20%, the remaining composition being a trans structure, and a Mooney viscosity of 20 to 120. Other rubber materials include acrylonitrile / butadiene rubber and styrene / butadiene rubber (usually "S
BR], or mixtures of the various rubbers mentioned above. In addition, the type of polymerization in the styrene / butadiene copolymer rubber of the present invention may be di-block.
Copolymerization, tri-block copolymerization, random (r
andom) copolymerization, star type copolymerization and the like are suitable. As the styrene / butadiene copolymer rubber, the weight ratio of styrene / butadiene ranges from 5/100 to 80/2.
0, usually 10/90 to 60/40, preferably with a molecular weight range of 5
It is preferably from 0,000 to 600,000. The rubber used in the present invention is preferably a butadiene-containing rubber, and more preferably a butadiene rubber alone or a combination of butadiene rubber and styrene / butadiene rubber.

The styrene monomer used for grafting to the rubber of the bulk or solution rubber graft copolymer of the present invention includes, for example, styrene, α-methylstyrene,
There are tertiary butyl styrene, p-methyl styrene, p-chloro styrene and the like, and it is particularly desirable to use styrene alone or styrene and α-methyl styrene in combination. Specific examples of the acrylonitrile monomer include acrylonitrile and α-methylacrylonitrile, and acrylonitrile is preferable. Further, monomers copolymerizable with styrene-based monomers and acrylonitrile-based monomers include, for example, methacrylate-based monomers, acrylate-based monomers, acrylic acid, methacrylic acid, and maleic anhydride. , N-substituted maleimides and the like. Examples of the methacrylate monomer include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, benzyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, 2-hydroxyethyl methacrylate, Glycidyl methacrylate, dimethylaminoethyl methacrylate, and acrylate-based monomers include methyl acrylate, butyl acrylate, N-phenylmaleimide, and the like; methyl methacrylate, butyl acrylate, N- Phenylmaleimide is preferred.

In the present invention, the bulk or solution rubber graft copolymer (A) is used in an amount of 1 to 30 parts by weight based on 100 parts by weight of the base resin.
Occupies part by weight. If it exceeds 30 parts by weight, the impact strength is poor, and if it is less than 1 part by weight, the flame retardancy becomes poor.

The emulsion rubber graft copolymer (B) of the present invention is a rubber latex 45 containing a diene monomer.
Styrene monomer 90-50% by weight in the presence of ~ 85 parts by weight
By graft polymerizing 55 to 15 parts by weight of a monomer mixture consisting of 10 to 50% by weight of an acrylonitrile monomer and 0 to 40% by weight of a monomer copolymerizable therewith, the weight average particle diameter is reduced. Emulsion rubber graft copolymer (B) containing rubber particles of 0.05 to 0.8 μm is obtained or latex of emulsion graft copolymer (B) having different average particle diameters of rubber is mixed to obtain a two-peak distribution. An emulsified rubber graft copolymer (B) is produced through coagulation, dehydration, drying and the like. As the diene-containing rubber latex, preferably a conjugated diene monomer 100
A homopolymer or a copolymer consisting of 0 to 60% by weight and 0 to 40% by weight of a copolymerizable unsaturated monomer.
er). The conjugated diene monomer is represented by the following formula.

[0016]

Embedded image

Wherein R is hydrogen, methyl or chlorine;
Examples of copolymerizable unsaturated monomers include styrene-based monomers, acrylonitrile-based monomers, methacrylate-based monomers, acrylate-based monomers, and mixtures thereof.

Representative rubber components of the conjugated diene rubber latex used in the present invention include polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, butadiene-methyl methacrylate copolymer, isoprene. -Butyl acrylate copolymer and the like. The conjugated diene rubber latex has a weight average particle diameter of 0.05 to 0.8 μm by direct polymerization with the monomer.
m, or may be polymerized into a rubber latex having a small particle size of 0.05 to 0.18 μm, and then further enlarged to a rubber latex of 0.2 to 0.8 μm by a known rubber enlarging method. Examples of the rubber enlargement method include a chemical enlargement method in which an organic acid, a metal salt or a polymer coagulant having a carboxylic acid group is added, a mechanical enlargement method by mechanical stirring, and a freeze enlargement method. As the polymer flocculant used in the chemical enlargement method, for example, butyl acrylate
There is a methacrylic acid copolymer.

As a method for producing the emulsion rubber graft copolymer (B), conventional graft polymerization means is commonly used. That is, a mixture of a styrene monomer, an acrylonitrile monomer, and a monomer copolymerizable therewith, if necessary, is subjected to a graft polymerization reaction in the presence of a rubbery polymer, and the grafted monomer is reacted. The styrene copolymer composed of the monomer is chemically bonded or grafted to the diene rubber. At this time, depending on the ratio of the monomer and the diene rubber and the polymerization conditions, the diene rubber is grafted, and
A styrenic copolymer with the desired graft thickness is obtained. Polymerization temperature in the graft polymerization reaction, type of initiator, physical or chemical properties of the rubbery polymer (for example,
Swelling index of rubber, copolymer composition and content of rubber),
Particle size, monomer addition speed, pre-impregnation degree of monomer and rubber, chain transfer agent, amount and type of emulsifier used, etc., all of the styrene copolymer grafted to diene rubber Affects graft thickness.

The amount of the polymerization initiator to be added to the graft polymerization reaction is usually in the range of 0.01 to 5.0 parts by weight, preferably 0.1 to 3.0 parts by weight, based on the monomer. The amount is determined according to the polymerization conditions.

The molecular weight of the graft copolymer is as follows:
It can be controlled by the temperature of the graft polymerization reaction and / or by adding a small proportion of known molecular weight regulators. Examples of the molecular weight regulator include a mercaptan compound, a halogen compound, a terpene compound and the like, and more specific examples include n-dodecyl mercaptan, tert-dodecyl mercaptan, and α-methylstyrene dimer.

The above-mentioned monomer mixture for graft polymerization is added all at once or batchwise or continuously. More preferably, the polymerization initiator is added simultaneously, continuously, batchwise or collectively. As the polymerization initiator, various known polymerization initiators for emulsifying radicals can be used, for example, peroxy compounds, azo compounds or persulfates, and as the peroxy compound, for example, dicumyl peroxide, tert-butyl peroxide, Benzoyl peroxide, cumene hydroperoxide, tert-butyl hydroperoxide and the like are suitable.

The polymerization reaction between the diene-containing rubber latex and the monomer mixture proceeds at a reaction temperature of 20 to 100 ° C. while stirring under an inert gas atmosphere.
Pressure may be applied up to PSIG. 90 monomers in the reaction system
%, Usually requires a polymerization time of 2 to 10 hours, preferably 3 to 8 hours.

In the present invention, the styrene-based monomer, acrylonitrile-based monomer and a monomer copolymerizable therewith are used in the above-mentioned bulky rubber-based graft copolymer (B). Alternatively, since it is the same as that exemplified for the solution rubber graft copolymer (A), the restatement is omitted.

According to the graft polymerization reaction, emulsified graft rubber particles having a weight-average particle size of 0.05 to 0.8 μm can be produced, and the particle size is distributed in a single mountain or a small particle size rubber latex before the enlargement is 0.05 to 0.18. μm and the expanded rubber latex having a larger particle size of 0.2 to 0.8 μm can be used as a rubber graft copolymer having a two-peak particle size distribution in an appropriate ratio, for example, 1: 1. .

The latex of the rubber graft copolymer having one or two peaks in the particle size distribution needs to be coagulated by adding an appropriate amount of a coagulant. In general, as the coagulant used, sulfuric acid, acids of acetic acid, alkaline earth metal salts, for example, calcium salts such as calcium chloride, magnesium chloride, magnesium salts such as magnesium sulfate,
There are aluminum salts such as aluminum sulfate, with alkaline earth metal salts being preferred. The coagulated polymer slurry is dewatered to remove water, and then dried to produce the emulsified rubber graft copolymer (B).

In the present invention, the emulsified rubber graft copolymer (B) accounts for 1 to 25 parts by weight based on 100 parts by weight of the base resin. If it exceeds 25 parts by weight, the impact strength is poor, and if it is less than 1 part by weight, the flame retardancy becomes poor.

The styrenic copolymer (C) in the present invention
Is obtained by polymerizing 89 to 20 parts by weight of a styrene monomer, 10 to 50 parts by weight of an acrylonitrile monomer, and 0 to 40 parts by weight of another copolymerizable monomer selected as necessary. Obtained. As the polymerization method, for example, lump, solution,
Examples include suspension or emulsification, and bulk or solution polymerization is preferred. The weight average molecular weight of the styrenic copolymer (C) is in the range of 60,000 to 400,000, and 80,000 to 300,000.
A range of 000 is preferred. Since the styrene-based monomer, acrylonitrile-based monomer and copolymerizable monomer are all the same as the monomers used for the bulk or solution rubber graft copolymer (A), Do not.

In the present invention, the styrenic copolymer (C)
Can be usually carried out in a continuous bulk or solution polymerization reactor. Examples of the reactor include a plug flow reactor, a complete mixing type reactor (CSTR), and a static mixer type plug flow reactor. Preferably, the reactor is a complete mixing type reactor. These can be used alone or in combination of one or more. In producing the styrenic copolymer (C) in the present invention, it may be carried out by thermal polymerization or by a catalytic polymerization method using a polymerization initiator. Examples of the polymerization initiator include acyl peroxide, ester peroxide, ketal peroxide, carbonate peroxide, and an azo compound having a nitrile group and a cyclohexyl group. The amount of the polymerization initiator is usually 0.01 to 1.0% by weight based on 100 parts by weight of the monomer.

The reaction temperature in the reactor is 80-200.
° C, preferably within the range of 90 to 160 ° C. Also,
Preferably, the pressure of the reactor is controlled between 1 and 5 kg / cm ^{2, and} the time during which the raw material solution stays in the reactor is controlled between 1 and 5 hours. In order to control the molecular weight of the polymer,
For example, a chain transfer agent such as n-dodecyl mercaptan, t-dodecyl mercaptan, and terpinolene may be used.

In the polymerization reaction, the conversion of the monomer is from 40 to 95.
%, The obtained copolymer solution is heated by a preheater, and an unreacted monomer and other volatile components are removed by devolatilization. The devolatilization process can usually use a devolatilizing device such as a vacuum degassing tank or an extruder. Volatile components are collected by a condenser to form a recovered liquid, and water in the recovered liquid is removed to re-use as a raw material solution. Can be used. If the polymer melt from which volatile components have been removed is extruded into particles, pellets of the styrene-based copolymer (C) used in the present invention can be obtained.

When the styrene copolymer (C) occupies 0 to 53 parts by weight based on 100 parts by weight of the base resin, it exhibits good properties as a resin composition. The total of the bulk or solution rubber graft copolymer, the emulsion rubber graft copolymer and the styrene copolymer, that is, the amount of the styrene resin is 2 to 55 parts by weight based on 100 parts by weight of the base resin.

In the present invention, the polycarbonate resin (D) is an aromatic polycarbonate, and may be any known homogeneous polycarbonate or polycarbonate copolymer, and may be linear or branched. The polycarbonate (D) can be produced by any known production method. For example, a polycondensation reaction (polycondensat
ion reaction) or transesterifica
option). These manufacturing processes,
Reactants, polymers, catalysts, solvents, reaction conditions and the like are conventionally known, and US Pat. No. 2,964,974, 29
No. 70137, No. 2999835, No. 3999846,
No. 3028365, No. 3153008, No. 3187065
No. 3215668 No. 3258414 No. 50101
No. 62. The polycarbonate (D)
The bisphenol which is a raw material of is, for example, dihydroxybiphenyl, bishydroxyphenylalkyl, bishydroxyphenyldialkyl, bishydroxyphenyl sulfide, bishydroxyphenyl ether, bishydroxyphenyl ketone, bishydroxyphenyl sulfoxide, bishydroxyphenyl sulfone, cyclohexyl It can be selected from bisphenols such as denbisphenols, core alkylated derivatives of these compounds, and mixtures thereof.

Specific examples of the bisphenol include 4,4'-dihydroxybiphenyl, 2,2-bis- (4-hydroxyphenyl) propane, and 2,4-bis- (4-hydroxyphenyl) -2. -Methylbutane,
1,1-bis- (4-hydroxyphenyl) cyclohexane, α, α-bis- (4-hydroxyphenyl) diisopropylbenzene, 2,2-bis- (3-methyl-4
-Hydroxyphenyl) -propane, 2,2-bis-
(3-chloro-4-hydroxyphenyl) -propane,
2,2-bis- (3,5-dimethyl-4-hydroxyphenyl) -propane, bis- (3,5-dimethyl-4-
(Hydroxyphenyl) -sulfone, 2,4-bis-
(3,5-dimethyl-4-hydroxyphenyl) -methylbutane, 1,1-bis- (3,5-dimethyl-4-hydroxyphenyl) -cyclohexane, α, α-bis-
(3,5-dimethyl-4-hydroxyphenyl) -paradiisopropylbenzene, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 2,2
-Bis- (3,5-dibromo-4-hydroxyphenyl) -propane and the like, and generally known as 2,2-bis- (4-hydroxyphenyl) -propane of bisphenol A is preferable. In addition, triphenol can be used for branching. The bisphenol is phosgene (pho
sgene) to obtain an aromatic polycarbonate, or by the production method and others disclosed in JP-A-1-158033, bisphenol and diphenyl carbonate were previously polymerized to a low molecular weight polymer. The polycarbonate can then be produced by reacting in the melt or by solid-state polymerization in a crystallization process.

The amount of the polycarbonate resin (D) used is 45 to 98 parts by weight with respect to 100 parts by weight of the base resin. When the amount is less than 45 parts by weight, the impact resistance is greatly reduced and the flame retardancy is reduced. Is also inferior.

In the present invention, aromatic polyphosphate (aromatic polyphosphate) added to the flame-retardant styrenic resin composition is used.
(E) can be represented by the following general formula.

[0037]

Embedded image

(Provided that R ¹ and R ² are the same or different lower alkyl or hydrogen, R ³ is hydrogen or lower alkyl or hydroxy, R ⁴ is hydrogen or lower alkyl, Y is a single bond, —C
H _2- , -C (CH ₃ ) _2- , -S-, -SO _2- , -CO-, -O- or -N =
N-, k represents 0 or 1, m represents an integer of 0 to 4, n represents an integer of 1, 2, 3, 4 or 5, and in the case of a mixture, an average of 0.5 to 4 In the case where R ¹ , R ² , and R ³ in the above general formula are lower alkyl groups,
C ₄ or less alkyl group, specific examples include methyl,
Ethyl and tert-butyl.

In the present invention, the amount of the aromatic polyphosphate (E) is from 1 to 30 parts by weight based on 100 parts by weight of the base resin.
Parts by weight. By using the aromatic polyphosphate (E), not only the flame retardancy is improved, but also a resin composition having good heat resistance and impact strength is obtained. Does not find any deposits and does not cause the "plate out" phenomenon. When other phosphorus-based flame retardants such as triphenyl phosphite, tolyl phosphate and diphenyl tolyl phosphate are used in place of the aromatic polyphosphate (E), heat resistance deteriorates, In addition, a plate-out phenomenon occurs during molding.

In the present invention, the so-called weight average particle size of the rubber particles refers to the term “microtom” from the resin composition.
e) After dyeing the thin film prepared in the above, about 200 to 1,00 in the enlarged photograph taken with a transmission electron microscope at a magnification of 10,000 times.
The particle size is measured for each of the 0 rubber dispersed particles, and the weight average particle size is determined by the following equation. Here, the particle size is a value obtained by dividing the sum of the maximum length and the minimum length of the rubber particles by two.

[0041]

(Equation 1)

[0042] (where, n _i = rubber particle size indicates the number of rubber particles D _i.).

In the present invention, it is necessary to add a tetrafluoroethylene polymer (F). Tetrafluoroethylene polymers (F) suitable for use according to the invention are
Polymers having a fluorine content of 65 to 76% by weight, preferably 70 to 76% by weight. Examples of such polymers are polytetrafluoroethylene, tetrafluoroethylene-hexafluoroethylene copolymers or tetrafluoroethylene copolymers containing small amounts of fluorine-free copolymerizable ethylenically unsaturated monomers. is there. These polymers are known substances and can be prepared in a known manner, for example from 7 to 71 kg / cm ^{2 in} an aqueous medium of tetrafluoroethylene using, for example, a free-radical forming catalyst such as sodium, potassium or ammonium persulfate. 0 to 200 under pressure
It can be prepared by polymerization at a temperature of 0.degree. C., preferably at a temperature of 20 to 100.degree. C. (more specifically, see, for example, US Pat. No. 2,393,967). These substances are
Density of 1.2 to 2.3 g / cm ³ and 0.05 depending on the shape used
And an average particle size of 1,000 μm.

The preferred tetrafluoroethylene polymer (F) according to the present invention has a thickness of 0.05 to 20 μm, preferably 0.1 to 0.2 μm.
Average particle size of 08 to 10 μm and 1.2 to 1.9 g / cm ³
Is used in the form of an agglomerated mixture of an emulsion of the tetrafluoroethylene polymer (F) and an emulsion of the emulsified rubber graft copolymer (B).

Suitable tetrafluoroethylene polymers (F) which can be used in powder form are, for example, from 100 to 1,000 μm.
m and a density of 2.0 g / cm ³ to 2.3 g / cm ³ . In the prior art, tetrafluoroethylene polymers are used as anti-dripping agents. UL (Underwri
For applications requiring a level of V-0 in the ter Laboratory standard, 0.02 to 2.0 parts by weight of the tetrafluoroethylene polymer (F) is used based on 100 parts by weight of the base resin. As an appropriate product, for example, the product name is Du Pont6CJ (Du
Polytetrafluoroethylene manufactured by Pont (USA), which is added in the form of a powder or in the form of an emulsion or by other methods during kneading.

The maleic anhydride copolymer (G) used in the present invention is effective for preventing thermal discoloration and preventing a decrease in strength. Maleic anhydride of 30 to 65% by weight of maleic anhydride and ethylene monomer are used. Is a low molecular weight copolymer. In this case, olefins such as 1-hexene, 1-nonene, 1-octadecene, etc.
Examples include styrene and alkyl vinyl ether, and styrene is particularly preferred. The weight average molecular weight of such a low molecular weight maleic anhydride copolymer is 800 to 25,000 and 1,200 to
22,000 is preferred, and a copolymer of 35-60% by weight of maleic anhydride and 65-40% by weight of styrene is preferred. The addition amount of the low molecular weight maleic anhydride copolymer (G) is 0.05 to 5.0 parts by weight, preferably 0.1 to 2.0 parts by weight, based on 100 parts by weight of the base resin in the present invention.

In the present invention, the rubber content of the bulk or solution rubber graft copolymer (A) in the flame-retardant styrenic resin composition is determined by the bulk or solution rubber graft copolymer (A).
3 to 40% by weight based on the total amount of the rubber in the emulsion rubber graft copolymer (B) and the content of the rubber in the emulsion rubber graft copolymer (B).
If the amount is more than 3% by weight, the impact strength of the resin is inferior, and the flame retardancy is also reduced.

The weight average particle size of the rubber particles in the flame-retardant styrenic resin composition is 0.3 to 2.0 μm, preferably 0.32 to 1.
When the average particle size is more than 2.0 μm, the impact strength of the resin is inferior, and the flame retardancy is reduced.
If it is less than μm, the impact resistance of the resin is significantly reduced.

Representative examples of the mixing step for obtaining the resin composition of the present invention include dry blending with a generally used Henschel mixer, followed by, for example, an extruder,
Melting and kneading with a mixer such as a kneader or a Banbury mixer.

The flame-retardant styrenic resin composition of the present invention is used as a molding material, and is applied to, for example, injection molding, extrusion molding, compression molding, blow molding, pressure molding, vacuum molding and the like.

The styrenic resin composition of the present invention may contain, if necessary, other additives such as an antioxidant, a plasticizer,
Add processing aids, UV stabilizers, UV absorbers, fillers, reinforcing agents, coloring agents, lubricants, antistatic agents, flame retardants, flame retardant aids, heat stabilizers, coupling agents or other additives No problem. These additives can be added during or after the polymerization reaction, before aggregation, or during extrusion kneading.

Examples of the antioxidant include phenolic antioxidants, thioether antioxidants, phosphorus antioxidants, chelating agents and the like. The amount of the phenolic antioxidant to be added is preferably 0.005 to 2.0% by weight based on the resin composition of the present invention. A typical example is octadecyl (3,5-bis tertiary butyl-4-). (Hydroxyphenyl) propionate, triethylene glycol bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], tetra [methylene-3- (3,5-bisthiate) Tert-butyl-4-hydroxyphenyl) propionate] methane, 2-tert.
Tert-butyl-6- (3-tert-butyl-2-hydroxy-
6-methylbenzyl) -4-methylphenylacrylate, 2,2'-methylene-bis (4-methyl-6
-Tert-butylphenol), 2,2'-thiobis (4
-Methyl-6-tert-butylphenol), 2,2'-
Thio-diethylene-bis [3- (3,5-bis-tert-butyl-4-hydroxyphenyl) propionic acid ester], 2,2'-ethylenediamide-bis [ethyl-3
-(3,5-bis tertiary butyl-4-hydroxyphenyl) propionic acid ester], butylated p-cresol and dicyclopentadiene adduct (for example, Wingstay L (trade name, manufactured by Goodyear, USA)) , Screw (4-
Hydroxy-3,5-di-tert-butylphenylpropionyl) hydrazide (for example, trade name Ir manufactured by Ciba (Switzerland))
ganox MD-1024), 2.2'-oxamidbis [ethyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and the like.

The thioether-based antioxidant is preferably added in an amount of 0.005 to 2.0% by weight based on the weight of the resin composition of the present invention. Typical examples thereof include dioctadecylthiodipropionate and dihexadecylthiodipropionate. Acid esters, pentaerythritol-tetra- (β-dodecyl-thiopropionate), bisoctadecylthioether and the like.

The phosphorus-based antioxidant includes a phosphite-based antioxidant or a phosphinic-ester-based antioxidant, the amount of which is 0.015 to the resin composition of the present invention.
~ 2.0% by weight is preferred. Representative examples include tri (nonylphenyl) phosphite, dodecyl phosphite, cycloneopentanetetrahydronaphthylbis (octadecyl phosphite), 4,4'-butylbis (3-methyl-6- Tertiary butylphenyl-bistridecanoyl phosphite), tri (2,4-tertiary butylphenyl) phosphite, tetra (2,4-
4-tert-butylphenyl) phosphite, tetra (2,4-tert-butylphenyl) -4,4′-diphenylenephosphinate, 9,10-dihydro-9-
Oxa-10-phosphaphenanthrene-10-oxide and the like.

The addition amount of the chelating agent is preferably 0.001 to 2.0% by weight, and typical examples thereof include dibenzoylmethane and sodium salt of ethylenediaminetetraacetic acid.

The total amount of the antioxidant added is usually 0.03 to 5.0% by weight based on the total content of the flame-retardant styrenic resin.

Representative examples of the lubricant include metal soaps such as calcium stearate, magnesium stearate, and lithium stearate, ethylenebisstearylamide, methylenebisstearylamide, palmitic amide, butyl stearate, and cetyl stearate. , Polypropylene glycol monostearate, n-
Compounds such as docosanoic acid and stearic acid, polyethylene wax, octacosanoic acid wax, carnauba wax, petroleum wax and the like can be mentioned. The total amount of the lubricant is 0.03 to 5.0% by weight based on the flame retardant styrenic resin composition. Further, in order to improve the extrudability and thermoformability of the resin, a methyl methacrylate-based processing aid may be used. Representative examples of the ultraviolet absorber include, for example, a benzotriazole-based compound, a benzophenone-based compound, and a cyanoacrylate-based compound. Further, there is a hindered amine compound as an ultraviolet stabilizer. When an ultraviolet absorber and an ultraviolet stabilizer are used, the total amount thereof is 0.02 to 2.0% by weight based on the flame retardant styrenic resin composition.

In order to improve the weather resistance of the resin, discoloration due to irradiation with ultraviolet rays, and deterioration of physical properties, it is preferable to use both a hindered amine ultraviolet stabilizer and an ultraviolet absorber in combination. For example, BASF's uvinul 4050
H (0.02 to 1.0% by weight) / uvinul 3035 (0.02 to 1.0% by weight).

Typical examples of the antistatic agent include low molecular weight compounds such as tertiary amine compounds and quaternary ammonium salt compounds, or permanent antistatic polymers such as polyamide polyether and polyethylene oxide. Substances. The amount of the permanent antistatic agent is usually 3 to 30% by weight based on the resin composition of the present invention.

Representative examples of the filler include calcium carbonate, silica, mica and the like.

Representative examples of the reinforcing agent include, for example, glass fiber, carbon fiber, and various whiskers.

Representative examples of the coloring agent include, for example, titanium oxide, iron oxide, graphite, and phthalocyanine dye.

Typical examples of the flame retardant or flame retardant auxiliary include brominated epoxy resin, monophosphate such as triphenyl phosphate, red phosphorus, antimony oxide, aluminum hydroxide, magnesium hydroxide, zinc borate. Melamine, melamine isocyanurate, silicone powder, expandable graphite and the like. When a monophosphate is used in combination, the content is preferably not more than 80% by weight, more preferably not more than 30% by weight of the aromatic polyphosphate.

Typical examples of the heat stabilizer include, for example,
Examples include dibutyltin maleate, basic magnesium, and aluminum hydroxycarbonate. The addition amount is usually 0.1 to 1.0 with respect to the styrene resin composition of the present invention.
% By weight.

Typical examples of the coupling agent include silane-based, titanate-based, and zirconate-based compounds.

The flame-retardant styrenic resin composition of the present invention may contain an appropriate amount of a polymer additive for modification. The polymer additive is a polymer produced by an appropriate method, for example, a styrene-N-phenylmaleimide copolymer, an N-phenylmaleimide content of 40% by weight.
Styrene-acrylonitrile-phenylmaleimide copolymer, high molecular weight styrene-maleic anhydride copolymer having a styrene content of 75% by weight or more and a weight average molecular weight of 50,000 to 400,000, and styrene imidized by reacting with aniline. Acrylonitrile-maleic anhydride copolymer, ungrafted crosslinked rubber, for example, acrylonitrile-butadiene rubber, polymethyl methacrylate, polyamide resin, polybutylene terephthalate, polybutylene terephthalate-based thermoplastic elastomer, polyphenylene ether,
Examples include a hydrogenated product of a maleic anhydride-modified styrene-butadiene-based thermoplastic elastic material, and various compatibilizers. These polymers are used in an amount of 3 to 200 parts by weight based on 100 parts by weight of the flame-retardant styrenic resin composition of the present invention.

[0067]

Next, the composition of the present invention will be described in more detail based on examples and physical property measurement data, but the present invention is not limited to these examples. In Examples, unless otherwise specified, "%" and "part" indicate "% by weight" and "part by weight", respectively.

[Production Example I-1] Preparation of solution rubber graft copolymer (A-1) 71% by weight of styrene, 23% by weight of acrylonitrile, and 6% by weight of polybutadiene rubber (ASADENE manufactured by Asahi Kasei Corporation)
55AS) was dissolved in a toluene solvent to form a feed solution, and then benzoyl peroxide and tertiary dodecylcaptan were pumped into each of the four polymerization tanks at a volume of 45 liters at temperatures of 97 ° C, 100 ° C, and 104 ° C, respectively. After the reaction is completed, the mixture is passed through a devolatilizer to remove volatile components, and the pelletized graft polymer is produced through extrusion granulation. . The graft polymer has a rubber content of 10.3% by weight, styrene
It is a solution rubber graft copolymer (A-1) comprising 68% by weight and acrylonitrile 22% by weight, and having a rubber particle weight average particle diameter of 1 μm.

[Production Example I-2] Production of Solution Rubber Graft Copolymer (A-2) The production method and composition were the same as those in Production Example I-1, except for the stirring speed of the polymerization reaction and other reaction conditions. Control
A solution rubber graft copolymer (A-2) having a weight average particle diameter of rubber particles of 6 μm is produced.

[0070] Production Example II-1] emulsified rubber graft copolymer (B-1) Preparation of Component Parts by weight of 1,3-butadiene 95.0 acrylonitrile 5.0 potassium persulfate 15.0 Sodium pyrophosphate 3.0 Potassium oleate 1.5 distilled water 140.0 Tertiary dodecyl mercaptan 0.2 When the combination of the above components is reacted at a reaction temperature of 65 ° C. for 12 hours, a synthetic rubber latex having a conversion of 94%, a solid content of about 40%, and a weight average particle size of about 0.1 μm is obtained. can get.

A polymer coagulant having a carboxyl group is prepared by the following components. Ingredients by weight n-butyl acrylate 85.0 acrylate 15.0 tertiary dodecyl mercaptan 0.3 potassium oleate 2.0 sodium dioctylsulfosuccinate 1.0 cumene hydroperoxide 0.4 sodium formaldehyde-modified sodium sulfate 0.3 distilled water 200.0 Reaction with the above composition The reaction was carried out at a temperature of 75 ° C. for 5 hours to obtain a carboxyl group-containing polymer flocculant having a conversion of 95% and a pH of 6.0.

Next, 100 parts by weight of the above synthetic rubber latex (solids) is enlarged by using 3 parts by weight of the polymer coagulant having a carboxyl group (solids) to obtain a pH 8.5 and a weight. An enlarged rubber latex having an average particle size of about 0.30 μm is produced.

Finally, using the enlarged rubber latex, a graft polymerization reaction is carried out according to the following formulation to produce an emulsified rubber graft copolymer (B-1). Ingredients by weight Inflated rubber latex (solid content) 100.0 Styrene 25.0 Acrylonitrile 8.3 Potassium oleate 1.2 Tertiary dodecyl mercaptan 0.2 Cumene hydroperoxide 0.5 Ferrous sulfate solution (0.2%) 3.0 Formaldehyde-modified sodium hyposulfate solution (10% 3.0) Sodium ethylenediaminetetraacetate solution (0.25%) 20.0 Distilled water 200.0.

Of the above blends, styrene / acrylonitrile was continuously supplied to the reaction system within 5 hours by a continuous addition method, and polymerization was carried out to obtain a rubber graft copolymer emulsion, which was then added with calcium chloride (CaCl ₂ ). Coagulation / dehydration and drying to a water content of 2% or less give a rubber graft copolymer (B-1) (rubber content 75% by weight) having a rubber particle weight average particle diameter of 0.3 μm.

[Production Example II-2] Production of Emulsion Rubber Graft Copolymer (B-2) Using the synthetic rubber latex produced in Production Example II-1, a graft polymerization reaction was directly carried out according to the following formulation. A graft rubber latex (B-2) having a rubber content of 50% was obtained. The weight average particle diameter of the rubber particles of the graft rubber latex (B-2) is 0.1 μm.

[0076] Component Parts by weight synthetic latex (solids) 100.0 styrene 75.0 acrylonitrile 25.0 potassium oleate 2.0 tertiary-dodecyl mercaptan 0.6 cumene hydroperoxide 1.4 sulfate ferrous solution (0.2%) 8.6 Formaldehyde reduction following sodium sulfate solution (10 %) 8.6 Sodium ethylenediaminetetraacetate solution (0.25%) 57.0 Distilled water 200.0.

[Production Example II-3] Production of Emulsified Rubber Graft Copolymer (B-3) The production method was the same as that in Production Example II-1, except that the recipe for the graft polymerization reaction was as follows. Change. Ingredients by weight Component Emulsified rubber emulsion (solid content) 100.0 Styrene 100.0 Acrylonitrile 50.0 Potassium oleate 1.2 Tertiary dodecyl mercaptan 0.2 Cumene hydroperoxide 0.5 Ferrous sulfate solution (0.2%) 3.0 Sodium formaldehyde sodium sulfate Solution (10%) 3.0 Sodium ethylenediaminetetraacetate solution (0.25%) 20.0 Distilled water 200.0 The graft rubber latex obtained by the above blending is coagulated and dehydrated with calcium chloride (CaCl ₂ ), and the water content is 2
%, The emulsion rubber graft copolymer (B-3) (rubber content 40% by weight) expected by the present invention is obtained. The weight average particle size of the rubber particles here is
0.50 μm.

[Production Example III] Styrene copolymer (C)
Preparation of 76% styrene and 24% acrylonitrile as raw materials, 0.025% by weight of ethylene bisstearyl amide, tertiary dodecyl mercaptan, and a recovered liquid obtained by devolatilizing and condensing volatiles by a reaction described below. The feed solution was combined and fed to a continuous kettle reactor having an internal temperature of 145 ° C. and a polymerization tank capacity of 45 liters with a stirrer. The reaction solution always contained 15% of toluene in the reaction solution. Also, the polymerization rate is kept at 56%.

If the reaction solution passes through a devolatilizer to separate volatile components, a styrene copolymer is obtained. On the other hand, the separated and recovered volatiles are condensed by a condenser to become a recovered liquid, and are continuously combined with the raw material mixture and reused. By controlling the amount of tertiary dodecyl mercaptan added, a styrene copolymer (C) having a melt index of 1.0 was obtained.

Example 1 5 parts by weight of the solution rubber graft copolymer (A-1) and the emulsified rubber graft copolymer (B
-1) A base resin comprising 7.1 parts by weight, 12.9 parts by weight of a styrene copolymer (C), and 75 parts by weight of a polycarbonate resin (D) (Iupilon E-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd.) was obtained. 16.3 parts by weight of aromatic polyphosphate (E) per 100 parts by weight of base resin, polytetrafluoroethylene (abbreviated as "PTFE", manufactured by Du Pont Co., Ltd., trade name 6CJ, powder particle diameter 500) μ
m, ρ = 2.2 g / cm ³ ) 0.6 parts by weight, maleic anhydride-styrene copolymer (weight average molecular weight 8,000, maleic anhydride
0.15 parts by weight of 40 mol% and 60 mol% of styrene) and 1.0 part by weight of dibutyltin maleate as a heat stabilizer were dry-blended using a Henschel mixer, and the raw material tank temperature was set to 210 to 230 ° C and the die adapter temperature was set to 220 ° C. Using a twin-screw extruder with an exhaust port, a pellet-shaped flame-retardant resin composition was obtained. Next, when the resin composition was measured, the weight average particle diameter of the rubber particles was 0.3 μm.
The rubber content of the bulk or solution rubber graft copolymer (A) accounted for 8.6% by weight of the total rubber content of the flame-retardant styrenic resin composition. At the same time, each physical property of the composition was measured, and the results are shown in Table 1.

The measurement criteria for the physical properties of the resin compositions of Example 1 and Examples and Comparative Examples described below are as follows.

(I) Izod impact strength (IZOD): AST
It is measured according to MD-256, and the unit is expressed in kg · cm / cm 2. (Ii) Vicat Softening Temperatur
e): Measured according to ASTM D-1525, and the unit is expressed in ° C. (Iii) UL94 vertical burn measurement: Underwriter Labo, USA
If the measurement is performed in accordance with the vertical flame measurement rules defined by the ratory (UL) and the vertical combustion measurement is passed, "○"
On the other hand, when not passing, it is represented by "x". (Iv) Plate out: The flame-retardant styrenic resin composition was injected at an injection pressure of 1,000 kg / cm ^{2 at} a temperature of 250 ° C.
Injection machine (Shingo Co., Ltd.)
100 times repeatedly by using SM-90) to check whether there is any deposit on the mold surface. The case where only a little oil stain adheres to the mold surface is indicated by “NO”, and the case where considerable oil stain adheres to the mold surface is indicated by “YES”. (V) Thermal discoloration resistance: The injection temperature of the flame-retardant styrenic resin composition is 260 ° C, and the residence time is 0 min and 40 min, respectively.
And the hue of the molded product was measured, and the heat discoloration resistance was evaluated according to the following criteria. YI ₀ −YI ₄₀ > 10 ×× II ₀ −YI ₄₀ = 10 to 5 ΔYI ₀ −YI ₄₀ <5 ... (where YI ₀ : Yellow Index of a molded article with a stay of 0 min) YI ₄₀ : Residence time 40min).

[Examples 2 to 7] Under the same operating conditions as in Example 1, the physical properties of the formulations shown in Table 1 were measured, and the results are shown in Table 1.

[Comparative Examples 1 to 6] Under the same operating conditions as in Example 1, the physical properties of the formulations shown in Table 2 were measured, and the results are shown in Table 2.

[0085]

[Table 1]

[0086]

[Table 2]

(Notes) * 1 ArDP: Aromatic diphosphate
sphate) A flame retardant, PX-200 manufactured by Daihachi Chemical Co., Ltd.
The n value of the formula (I) is 1.0. * 2 Polycarbonate resin (D): Iupilon E-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd. * 3 PTFE: Polytetrafluroethylene (Du Pont, USA), trade name
6CJ.

As shown in Table 1, the test result of Comparative Example 1 shows that the rubber content of the bulk or solution rubber graft copolymer (A) was reduced to the total rubber content in the flame-retardant styrenic resin composition. On the other hand, when it is lower than 3% by weight and the weight average particle diameter of the rubber particles of the resin composition is less than 0.3 μm, it is found that the impact strength of the resin composition is significantly reduced. Indicates that if the resin composition does not contain the bulk or solution rubber graft copolymer (A), the flame retardancy is reduced and the composition cannot pass the vertical combustion test. When the content of the polycarbonate-based resin (D) is lower than 45% by weight, the impact strength of the resin composition is significantly reduced, the softening point is also reduced, and it cannot be passed to the vertical combustion measurement. Lump or solution rubber in resin composition The total rubber content of the rubber content of the resin composition of the raft copolymer (A) 40 wt%
If the weight average particle size of the rubber particles in the resin composition is larger than 2 μm, it is evident from Comparative Example 5 that the impact strength of the resin decreases and the resin cannot pass the vertical combustion test. It was found that the impact strength of the sample was lowered, and that it did not pass the vertical combustion test.
When PTFE is not added, dripping occurs, and it can be seen that a vertical combustion test cannot be passed.

On the other hand, from Examples 1 to 7, the ratio of each component and the amount used are limited to the ranges specified in the present invention, whereby the heat resistance is excellent, the impact strength is high, and the strength is prevented from decreasing. It can be seen that a flame-retardant styrenic resin composition for a molding material that has properties of improving heat discoloration resistance and preventing dripping and that does not cause a plate-out phenomenon during injection molding can be produced.

Example 8 18 parts by weight of the solution rubber graft copolymer (A-1) and the emulsified rubber graft copolymer (B
-1) 4.5 parts by weight of an emulsified rubber graft copolymer (B-
2) 4.5 parts by weight, 73 parts by weight of a polycarbonate resin (D) (Jupilon E-2000, manufactured by Mitsubishi Gas Chemical Co., Ltd.), maleic anhydride-octadecene-1 copolymer (maleic anhydride 52 mol%, octadecene- 1 48 mol%, weight average molecular weight 15,000) 0.3 part by weight was dry-blended using a Henschel mixer, and the temperature of the raw material tank was 230 to 250
C., the die adapter temperature was 245.degree. C., and a pellet base resin was produced using a twin-screw extruder with an exhaust port. Then, 100 parts by weight of the above base resin, resorcinol bis (diphenyl phosphate) flame retardant [resorcinol bis-
(diphenyl phosphate), abbreviated as “RDP”, AKZO
(USA), product name "FYROFLEX RDP"]
14 parts by weight, triphenyl phosphite (triphenyl
phosphate, abbreviated as “TPP”, manufactured by FMC (USA)]
2 parts by weight (the average value of n in formula (I) of the flame retardant mixture obtained by mixing RDP and TPP is 0.91), PTFE (the above
DuPont 6CJ) 0.8 parts by weight and 1.0 part by weight of dibutyltin maleate as a heat stabilizer were dry-blended using a Henschel mixer, and the raw material tank temperature was 220 to 240 ° C and the die adapter temperature was 235 ° C. Using a twin-screw extruder with an exhaust port, a flame-retardant resin composition in the form of pellets was obtained. Further, when the resin composition was measured, the weight average particle diameter of the rubber particles was 0.42 μm, and the rubber content of the bulk or solution rubber graft copolymer (A) was that of the flame-retardant styrene resin composition. 25% by weight of total rubber content
Was occupied. At the same time, the results of measuring the physical properties of the composition were as follows: Izod impact strength (1/8 ") 66 kg · cm / c
m, softening point 99 ° C, UL94 vertical combustion test V-0 (1-16 ")
No heat-induced discoloration was observed, and the heat-resistant discoloration was good (the heat-resistant discoloration test rank is ○).

[Comparative Example 7] A processing method similar to that of Example 8 is employed. The difference is that maleic anhydride-octadecene-1 copolymer is not included. The physical properties of the obtained flame-retardant styrenic resin composition were measured. The results were as follows: Izod impact strength (1/8 ") 45 kg · cm / cm, softening point 98 ° C,
No pass and plate-out phenomena occur in the UL94 vertical burning test V-0 (1-16 "), but it cannot pass the measurement of heat discoloration resistance (the rank of the heat discoloration test is x).

The results of Example 8 and Comparative Example 7 show that when the maleic anhydride-ethylene copolymer (G) was not added, the impact strength of the resin was lowered and the resin could not pass the measurement of heat discoloration resistance. I understand.

Comparative Example 8 10 parts by weight of the solution rubber graft copolymer (A-1) and the emulsified rubber graft copolymer (B
-1) 6.4 parts by weight, 8.6 parts by weight of styrene copolymer, polycarbonate resin (D) (Mitsubishi Gas Chemical Co., Ltd., Ju
pilon E-2000) 75 parts by weight, maleic anhydride-styrene copolymer (maleic anhydride 40 mol%, styrene 60 mol%, weight average molecular weight 8,000) 0.15 parts by weight, TPP (the above-mentioned FPP TPP) 16.7 parts by weight Part, PTFE (Du described above)
Pont Co., Ltd. 6CJ) 0.6 parts by weight and 1.0 part by weight of dibutyltin maleate as a heat stabilizer were dry-blended using a Henschel mixer, and the temperature of the raw material bath was further reduced.
Using a twin-screw extruder equipped with an exhaust port at 220 to 240 ° C and a die adapter temperature of 235 ° C, a pellet-shaped flame-retardant resin composition was obtained. Furthermore, when the resin composition was measured, the weight average particle diameter of the rubber particles was 0.4 μm, and the rubber content of the solution rubber graft copolymer (A) was the total rubber content of the flame-retardant styrene resin composition. Accounted for 17.2% by weight of the amount. At the same time, each physical property of the composition was measured, and the results were Izod impact strength (1/8 ") 70 kg · cm / cm, UL94
It passes the vertical combustion test V-0 (1-16 ") and has good heat discoloration resistance. However, when the softening point is 95 ° C., it is greatly reduced and a plate-out phenomenon occurs.

[0094]

As is clear from the above examples, in the present invention, by limiting the ratio and the use amount of each component, excellent heat resistance, high impact strength, prevention of strength reduction,
Has the property of improving heat discoloration resistance and preventing dripping,
In addition, a flame-retardant styrene-based resin composition for a molding material that does not cause a plate-out phenomenon during injection molding can be produced. Therefore, the present invention is not only novel but also has great industrial application.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 27:18 35:00)

Claims (2)

[Claims] (1) 1 to 30 parts by weight of a bulk or solution rubber graft copolymer (A) containing rubber particles having a weight average particle diameter of 0.5 to 10 μm; and (2) a weight average particle diameter of 0.05 to 10 μm. 2 to 55 parts by weight of a styrene resin comprising 1 to 25 parts by weight of an emulsion rubber graft copolymer (B) containing 0.8 μm rubber particles and (3) 0 to 53 parts by weight of a styrene copolymer (C) 100 parts by weight of a base resin comprising 45 to 98 parts by weight of a polycarbonate resin (D), 1 to 30 parts by weight of (2) an aromatic polyphosphate (E), and (3) a tetrafluoroethylene polymer (F ) 0.02 to 2.0 parts by weight, and (4) a low molecular weight maleic anhydride copolymer (G) 0.05 comprising maleic anhydride and an ethylene monomer having a weight average molecular weight of 800 to 25,000 and maleic anhydride of 30 to 65% by weight. A flame-retardant styrenic resin composition for a molding material comprising: The rubber content of the bulk or solution rubber graft copolymer (A) is equal to the sum of the rubber amount in the bulk or solution rubber graft copolymer (A) and the rubber amount in the emulsion rubber graft copolymer (B). 3 to 40% by weight, and the weight average particle diameter of the rubber particles in the flame-retardant styrenic resin composition is 0.3 to 0.3% by weight.
A flame-retardant styrenic resin composition for a molding material, characterized by having a thickness of from 2 to 2 m. 2. The rubber composition according to claim 1, wherein the weight average particle diameter of the rubber particles in the flame-retardant styrenic resin composition is 0.32 to 1.2 μm.
3. The flame-retardant styrenic resin composition according to item 1.