JP2005105186A - Flame-retardant resin composition and molded article composed of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a flame-retardant resin composition comprising a rubber-reinforced styrene resin which exhibits high-degree flame retardancy without using a halogen-containing organic compound and exhibits excellent light resistance and transparency without detriment to excellent mechanical properties inherent in the rubber-reinforced styrene resin. <P>SOLUTION: The flame-retardant resin composition comprises (A) 100 pts. wt. of the rubber-reinforced styrene resin and, incorporated therewith, (B) 1-30 pts. wt. of a phosphorus flame-retardant and (C) 0.1-20 pts. wt. of an epoxy resin represented by general formula (1) (wherein R<SP>1</SP>-R<SP>9</SP>are the same or different and are each a hydrogen atom, a 1-8C alkyl group or an aryl group; and n is an average and is larger than 0 and at most 10), and has a total light transmittance of at least 60% at 23°C. The molded article is composed of the same. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a flame retardant resin composition excellent in flame retardancy, light resistance, and transparency, and a molded article comprising the same, without impairing the inherent mechanical properties of the rubber-reinforced styrene resin.

  Conventionally, rubber-reinforced styrene-based resins have been used in a wide range of fields such as home electric appliances, OA appliances, automobiles and the like due to their excellent mechanical properties and molding processability. However, depending on the application, flame retardancy is necessary from the viewpoint of safety, and various techniques have been proposed for this flame retardancy.

  In general, a method in which a flame retardant such as a bromine compound having high flame retardant efficiency and antimony oxide are mixed with a resin to make it flame retardant is employed. However, this method has problems such as a large amount of smoke generated during combustion.

  Therefore, as a non-halogen flame retardant, a typical phosphoric ester of a phosphorous flame retardant has been often used, and a technique for adding a phosphoric ester compound to a rubber-reinforced styrene resin with transparency is disclosed. (See Patent Document 1). However, the rubber-reinforced styrene-based resin imparted with transparency is further increased in combustibility because it is copolymerized with an unsaturated carboxylic acid alkyl ester. Therefore, the compatibility between flame retardancy and transparency could not be solved.

  Moreover, in order to improve a flame retardance, the method of adding a phosphorus flame retardant to a polycarbonate resin and a rubber reinforced styrene resin is disclosed (Patent Document 2). However, the transparency of the resulting composition was actually reduced.

  Addition of low-molecular-weight epoxy compound to rubber-reinforced styrene resin and phosphorous flame retardant with transparency as a technique to achieve both flame retardancy and transparency in rubber-reinforced styrene resin with transparency. (Patent Document 3) or a method of adding a modified phenolic resin (Patent Documents 4 and 5) is disclosed. However, in order to express flame retardancy in any case, a large amount of phosphate ester must be blended, and thus the problem that the mechanical properties deteriorate has not been solved.

Moreover, the method of adding the epoxy resin of a specific structure to a thermoplastic resin and a phosphorus flame retardant is disclosed (patent document 6). However, in the method of this patent document, transparency is not taken into consideration, and the disclosed technology does not provide a resin composition that achieves both flame retardancy and transparency.
JP 2000-344994 A JP 2002-194100 A JP 2002-138182 A JP 2002-201330 A JP 2002-206039 A JP 2003-138135 A

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue.

  Accordingly, an object of the present invention is to have a high flame resistance without using a halogen-based organic compound with respect to a rubber-reinforced styrene resin, and at the same time, without impairing the original excellent mechanical properties of the rubber-reinforced styrene resin. It is providing the flame-retardant resin composition excellent in property, and also transparency, and a molded article consisting thereof.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have high flame retardancy at the same time by blending a rubber-reinforced styrene resin with a phosphorus flame retardant and a specific epoxy resin. The present inventors have found that a flame-retardant resin composition having excellent light resistance and transparency can be obtained without impairing the mechanical properties inherent to rubber-reinforced styrene resins.

  That is, the flame retardant resin composition of the present invention is “(A) 1 to 30 parts by weight of a phosphorus-based flame retardant with respect to 100 parts by weight of a rubber-reinforced styrene resin, and (C) the following general formula ( A flame retardant resin composition containing 0.1 to 20 parts by weight of the epoxy resin represented by 1) and having a total light transmittance of 60% or more measured at 23 ° C. ”.

(In the above formula (1), X represents a group represented by the above general formula (2) or (3), and R1 to R9 are the same or different hydrogen atoms, alkyl groups having 1 to 8 carbon atoms, and aryl groups. (In addition, n represents an average value and is a value greater than 0 and 10 or less.)

  The flame retardant resin composition of the present invention and a molded article comprising the same are excellent in flame retardancy, light resistance, and transparency, without impairing the original excellent mechanical properties of the rubber-reinforced styrene resin. A composition is obtained.

  Hereinafter, the flame retardant resin composition of the present invention and a molded product made thereof will be described in detail.

  The (A) rubber-reinforced styrene-based resin in the present invention includes a structure in which a (co) polymer containing a styrene monomer is grafted to a rubbery polymer, and a styrene monomer (co-polymer). ) A polymer having a structure in which a rubbery polymer is not grafted is included.

  Examples of such (A) rubber-reinforced styrene resin include impact-resistant polystyrene (HIPS), ABS resin (acrylonitrile-butadiene rubber-styrene copolymer), and AAS resin (acrylonitrile-acrylic rubber-styrene copolymer). ), And AES resin (acrylonitrile-ethylenepropylene rubber-styrene copolymer).

  Specifically, in the presence of a rubbery polymer, (a) an unsaturated carboxylic acid alkyl ester monomer, (b) an aromatic vinyl monomer, (c) a vinyl cyanide monomer, and (D) (A-1) graft copolymer obtained by copolymerizing a monomer mixture composed of other vinyl monomers copolymerizable with these, and (a) an unsaturated carboxylic acid alkyl ester monomer (B) aromatic vinyl monomer, (c) vinyl cyanide monomer, and (d) other vinyl monomers copolymerizable therewith. (A-2) vinyl copolymer It consists of a polymer.

  In the (A) rubber-reinforced styrene-based resin of the present invention, the rubbery polymer used for the (A-1) graft copolymer is not particularly limited, but diene rubber, acrylic rubber, ethylene rubber, etc. Can be used. Specific examples of these rubbery polymers include polybutadiene, styrene-butadiene copolymer, block copolymer of styrene-butadiene, acrylonitrile-butadiene copolymer, butyl acrylate-butadiene copolymer, polyisoprene, butadiene- Methyl methacrylate copolymer, butyl acrylate-methyl methacrylate copolymer, butadiene-ethyl acrylate copolymer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, ethylene-isoprene copolymer And ethylene-methyl acrylate copolymer. Among these rubber polymers, polybutadiene, styrene-butadiene copolymer, styrene-butadiene block copolymer and acrylonitrile-butadiene copolymer are particularly preferably used from the viewpoint of impact resistance.

  These rubbery polymers can be used in one kind or a mixture of two or more, but when used in a mixture of two or more, an Abbe refractometer is used from the viewpoint of transparency. It is preferable to select two or more rubbery polymers so that the measured refractive index difference is 0.03 or less.

  The weight average particle diameter of the rubbery polymer constituting the (A-1) graft copolymer in the present invention is not particularly limited, but is in the range of 0.1 to 0.5 μm, particularly 0.15 to 0.4 μm. It is preferable that By making the weight average particle diameter of the rubbery polymer in the range of 0.1 μm to less than 0.5 μm, it is possible to achieve both impact resistance and transparency.

  In addition, the weight average particle diameter of the rubbery polymer is a sodium alginate method described in “Rubber Age, Vol. 88, p. 484 to 490, (1960), by E. Schmidt, P. H. Biddison”. Using the fact that the diameter of the polybutadiene particles to be creamed differs depending on the concentration of sodium alginate, measure the particle size of 50% cumulative weight fraction from the creamed weight fraction and the cumulative weight fraction of sodium alginate concentration. Can do.

  The (a) unsaturated carboxylic acid alkyl ester monomer used for the (A-1) graft copolymer and (A-2) vinyl copolymer in the present invention is not particularly limited. Acrylic acid esters and / or methacrylic acid esters having 6 alkyl groups or substituted alkyl groups are preferred.

  Specific examples of (a) unsaturated carboxylic acid alkyl ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and n-butyl (meth) acrylate. T-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2- (meth) acrylic acid 2- Hydroxyethyl, 3-hydroxypropyl (meth) acrylate, 2,3,4,5,6-pentahydroxyhexyl (meth) acrylate and 2,3,4,5-tetrahydroxypentyl (meth) acrylate Among them, methyl methacrylate is most preferably used. These can be used alone or in combination of two or more thereof.

  The (b) aromatic vinyl monomer used in the (A-1) graft copolymer and (A-2) vinyl copolymer in the present invention is not particularly limited, and specific examples include styrene, α-methyl styrene, o-methyl styrene, p-methyl styrene, o-ethyl styrene, p-ethyl styrene, pt-butyl styrene and the like can be mentioned, among which styrene and α-methyl styrene are preferably used. These can use 1 type (s) or 2 or more types.

  The (c) vinyl cyanide monomer used in the (A-1) graft copolymer and (A-2) vinyl copolymer in the present invention is not particularly limited, and specific examples include acrylonitrile, methacrylo Nitrile and ethacrylonitrile are exemplified, and among these, acrylonitrile is preferably used. These can use 1 type (s) or 2 or more types.

  Further, (a) an unsaturated carboxylic acid alkyl ester monomer constituting the (A-1) graft copolymer and (A-2) vinyl copolymer in the present invention, and (b) an aromatic vinyl monomer. There are no particular restrictions on the monomer and (c) other vinyl monomers that can be copolymerized with the vinyl cyanide monomer. Specific examples include (meth) acrylic acid and (meth) acrylic. Glycidyl acid, glycidyl itaconate, allyl glycidyl ether, styrene-p-glycidyl ether, p-glycidyl styrene, maleic acid, maleic anhydride, monoethyl maleate, itaconic acid, itaconic anhydride, phthalic acid, N-methylmaleimide N-ethylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, acrylamide, methacrylamide, N-methyla Rilamide, butoxymethylacrylamide, N-propylmethacrylamide, aminoethyl acrylate, propylaminoethyl acrylate, dimethylaminoethyl methacrylate, ethylaminopropyl methacrylate, phenylaminoethyl methacrylate, cyclohexylaminoethyl methacrylate, N-vinyl Examples include diethylamine, N-acetylvinylamine, allylamine, methallylamine, N-methylallylamine, p-aminostyrene, 2-isopropenyl-oxazoline, 2-vinyl-oxazoline, 2-acryloyl-oxazoline and 2-styryl-oxazoline. These can be used alone or in combination of two or more.

  In the present invention, the (A-1) graft copolymer is a monomer in the presence of 10 to 80 parts by weight, preferably 20 to 70 parts by weight, more preferably 30 to 60 parts by weight of a rubbery polymer. It is obtained by copolymerizing 20 to 90 parts by weight of the mixture, preferably 30 to 80 parts by weight, more preferably 40 to 70 parts by weight. Even if the ratio of the rubbery polymer is less than the above range or exceeds the above range, the impact strength and the surface appearance may be deteriorated.

  Moreover, the preferable ratio of the monomer mixture used for the (A-1) graft copolymer and the (A-2) vinyl copolymer is such that (a) the unsaturated carboxylic acid alkyl ester monomer is 50 to 50%. 90% by weight, more preferably 60-80% by weight, (b) 9-49% by weight of aromatic vinyl monomer, more preferably 17-37% by weight, (c) vinyl cyanide monomer 1 to 30% by weight, more preferably 3 to 10% by weight. (D) By using other vinyl monomers copolymerizable with these at 30% by weight or less, good transparency, Impact properties and moldability can be obtained.

  The (A-1) graft copolymer may contain a non-grafted copolymer that is produced when the monomer mixture is graft copolymerized with the rubber polymer. However, the graft ratio is preferably 10 to 100% from the viewpoint of impact strength. Here, the graft ratio is the weight ratio of the grafted monomer mixture to the rubbery polymer. In addition, the intrinsic viscosity measured at 30 ° C. in a methyl ethyl ketone solvent of the ungrafted copolymer is not particularly limited, but 0.1 to 0.6 dl / g is a balance between impact strength and moldability. From the viewpoint of, it is preferably used.

  The intrinsic viscosity measured at 30 ° C. in the methyl ethyl ketone solvent of the (A-2) vinyl copolymer in the present invention is not particularly limited, but is 0.2 to 1.0 dl / g, particularly 0.3 to 0.00. 7 dl / g is preferably used from the viewpoint of the balance between impact strength and moldability.

  There are no particular limitations on the method for producing the (A-1) graft copolymer and (A-2) vinyl copolymer in the present invention, and known heavy polymers such as bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization can be used. It can be obtained by law.

  The mixing ratio of the (A-1) graft copolymer and the (A-2) vinyl copolymer constituting the rubber-reinforced styrene resin of the present invention is (A-1) 10 to 100 weights of the graft copolymer. Parts, preferably 20 to 60 parts by weight, and (A-2) vinyl copolymer 0 to 90 parts by weight, preferably 40 to 80 parts by weight. (A-1) If the graft copolymer is less than the above range, sufficient impact resistance cannot be obtained.

  Furthermore, the content of the rubbery polymer contained in the rubber-reinforced styrene resin of the present invention is 5 to 30% by weight, preferably 10 to 20% by weight. By setting the content of the rubbery polymer in the range of 5 to 30% by weight, impact resistance and molding processability can be sufficiently satisfied.

  In addition, (A-1) the component excluding the rubber of the graft polymer and (A-2) the refractive index of the vinyl copolymer, and (A-1) the refraction of the rubbery polymer used in the graft polymer. From the viewpoint of transparency, it is preferable to adjust the composition ratio of the monomers so that the difference from the rate is 0.03 or less, more preferably 0.02 or less. A plurality of such (A-1) graft polymers and (A-2) vinyl copolymers may be used.

  The (B) phosphorus flame retardant used in the present invention is not particularly limited as long as it is an organic or inorganic compound containing phosphorus, such as ammonium polyphosphate, polyphosphazene, phosphate, phosphonate, phosphinate, and phosphine oxide. Is mentioned. Of these, polyphosphazenes and phosphates are preferable, and aromatic phosphates can be particularly preferably used.

  Of the phosphoric flame retardant (B) used in the present invention, the aromatic phosphate is represented by the following general formula (4).

  First, the structure of the flame retardant represented by the above formula (4) will be described.

In said formula (4), n is an integer greater than or equal to 0, and the mixture of different n may be sufficient. K and m are each an integer of 0 or more and 2 or less, and (k + m) is an integer of 0 or more and 2 or less, preferably k or m is an integer of 0 or more and 1 or less, particularly preferably k. , M are each 1. Moreover, in said formula (4), Y represents group shown by the said general formula (5), (6) or (7), R10-R17 is the same or different hydrogen atom or carbon number 1-5. Represents an alkyl group. Specific examples of the alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group. A hydrogen atom, a methyl group, and an ethyl group are preferable, and hydrogen is particularly preferable. Z represents a direct bond, O, S, SO ₂ , C (CH ₃ ) ₂ , CH ₂ , or CHPh, and Ph represents a phenyl group. Ar ¹ , Ar ² , Ar ³ and Ar ⁴ represent the same or different phenyl groups or phenyl groups substituted with halogen-free organic residues. Specific examples include phenyl group, tolyl group, xylyl group, cumenyl group, mesityl group, naphthyl group, indenyl group, anthryl group, etc., but phenyl group, tolyl group, xylyl group, cumenyl group, naphthyl group are preferable. In particular, a phenyl group, a tolyl group, and a xylyl group are preferable.

  The amount of the (B) phosphorus flame retardant used is 1 to 30 parts by weight, preferably 2 to 20 parts by weight, based on 100 parts by weight of the (A) rubber-reinforced styrene resin.

  (B) If the addition amount of the phosphorus-based flame retardant is less than the above range, a high flame retardancy imparting effect cannot be obtained, and if it exceeds the above range, the impact resistance is reduced and the surface appearance of the molded product is deteriorated. It tends to lose.

The (C) epoxy resin used in the present invention is represented by the above general formula (1).
In said formula (1), X represents the said general formula (2) or (3), R1-R9 represents either the same or different hydrogen atom, a C1-C8 alkyl group, and an aryl group. Specific examples of the alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, and a tert-butyl group. A hydrogen atom and a methyl group are preferable. N represents an average value and is a value greater than 0 and 10 or less.

  Examples of the method for obtaining the epoxy resin (C) used in the present invention include the following methods. First, the following formula (8)

(Wherein W represents a halogen atom, a hydroxyl group or a lower alkoxy group. R ⁸ and R ⁹ have the same meaning as in formula (3) above) or two or more vinyl groups. Polyphenols are obtained by a condensation reaction of any of the aromatic compounds and phenols in the presence of an acid catalyst. Next, the target epoxy resin is obtained by carrying out the reaction between the polyphenols and epihalohydrin in the presence of an alkali metal hydroxide.

  Preferred examples of the halogen atom represented by W in the formula (8) include a chlorine atom and a bromine atom, and examples of the lower alkoxy group include a methoxy group and an ethoxy group. These may be used alone or in combination of two or more.

  Examples of the aromatic compound having two or more vinyl groups include divinylbenzene, alkyldivinylbenzene, diallyl phthalate, and the like, and divinylbenzene is preferable in terms of reactivity and workability. These may be used alone or in combination of two or more.

  Examples of phenols include aromatic compounds having one phenolic hydroxyl group in one molecule. Specific examples include phenol, cresol, ethylphenol, n-propylphenol, isobutylphenol, t-butylphenol, xylenol, and methyl. Various o-, m-, and p-isomers of alkylphenols such as butylphenol and di-t-butylphenol, or various o-, m-, and p-isomers of vinylphenol, allylphenol, propenylphenol, and ethynylphenol, or cyclopentyl Examples thereof include cycloalkylphenols such as phenol, cyclohexylphenol and cyclohexylresole, and substituted phenols such as phenylphenol. These phenols can be used alone or in combination of two or more.

  The amount of the phenol used is 0.5 to 20 mol, preferably 2 to 1 mol of the compound represented by the above formula (8) and any one of the aromatic compounds having two or more vinyl groups. 15 moles.

  Various acid catalysts can be used for the condensation reaction to obtain polyphenols, but inorganic or organic acids such as hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, oxalic acid, boron trifluoride, anhydrous chloride Lewis acids such as aluminum and zinc chloride are preferable, and p-toluenesulfonic acid, hydrochloric acid, and sulfuric acid are particularly preferable. The amount of these acid catalysts to be used is not particularly limited, but with respect to 1 mol of the compound represented by the above formula (8) and the aromatic compound having two or more vinyl groups, 0.001-0.05 mol is preferable, More preferably, it is 0.002-0.02 mol.

  The condensation reaction for obtaining polyphenols can be carried out in the absence of a solvent or in the presence of an organic solvent. Specific examples in the case of using an organic solvent include toluene, xylene, methyl isobutyl ketone and the like. The amount of the organic solvent used is preferably 50 to 300% by weight, particularly preferably 100 to 250% by weight, based on the total weight of the charged raw materials. The reaction temperature is preferably 40 to 180 ° C., and the reaction time is preferably 1 to 15 hours.

  A known method can be employed for the reaction between the polyphenols obtained by the above condensation reaction and epihalohydrin. That is, after dissolving polyphenols in epihalohydrin, the target epoxy resin is obtained by reacting at a temperature of 20 to 120 ° C. in the presence of an alkali metal hydroxide.

  Further, a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide, trimethylammonium chloride or the like is added to a dissolved mixture of polyphenols and epihalohydrin as a catalyst, and the compound obtained by reacting at 50 to 150 ° C. with an alkali metal A method of adding a hydroxide and reacting again at a temperature of 20 to 120 ° C. can also be adopted.

  Usually, the amount of the alkali metal hydroxide used in the above reaction is 0.8 to 1.5 mol, preferably 0.9 to 1.1 mol, per 1 equivalent of the hydroxyl group of the polyphenol.

  The reaction product of these epoxidation reactions is washed with water or without washing with water, and the epihalohydrin and other added solvents are removed under reduced pressure. In addition, in order to obtain an epoxy resin having a lower hydrolyzable halogen content, the obtained epoxy resin is dissolved again in toluene, xylene, etc., reacted with an alkali metal hydroxide, and the resulting salt is filtered and washed with water. It may be removed by heating and drying under reduced pressure.

  The epoxy resin obtained above can be used singly or in combination as required.

  The addition amount of the (C) epoxy resin used in the present invention is 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the (A) rubber-reinforced styrene resin. . (C) When the addition amount of an epoxy resin is less than 0.1 weight part, since the high flame retardance provision effect is not seen, it is unpreferable. On the other hand, if it exceeds 20 parts by weight, not only the impact resistance is deteriorated and the surface appearance of the molded product is impaired, but also the transparency is remarkably lowered, which is not preferable.

  Thus, the flame retardant resin composition of the present invention comprising (A) a rubber-reinforced styrene resin, (B) an adjacent flame retardant, and (C) an epoxy resin in the above proportions was measured at 23 ° C. Light transmittance, in detail, using a direct reading haze meter manufactured by Toyo Seiki Co., Ltd., the total light transmittance value (%) measured at 23 ° C. for a 3 mm thick square plate is 60% or more, preferably 70% or more. It is desirable that it exhibits excellent transparency by satisfying such total light transmittance.

  Furthermore, for the flame retardant resin composition of the present invention, antioxidants and heat stabilizers such as hindered phenol-based, phosphorus-based, sulfur-based, and thioether-based antioxidants are within the range not impairing the object of the present invention. UV absorbers (for example, resorcinol, salicylate, benzotriazole, benzophenone, etc.), lubricants and mold release agents (such as montanic acid and salts thereof, esters thereof, half esters thereof, stearyl alcohol, stellar amide and ethylene wax), anti-coloring agents Flame retardants, nucleating agents, plasticizers, antistatic agents, and dyes / pigments that control the spread of fire and the amount of heat generated during combustion (such as phosphites and hypophosphites), fluororesins and silicone compounds Add one or more normal additives such as colorants containing cadmium sulfide (such as cadmium sulfide, phthalocyanine, titanium oxide) It can be.

  Moreover, the flame-retardant resin composition of the present invention is usually produced by a known method. For example, (A) rubber-reinforced styrene resin, (B) adjacent flame retardant, (C) epoxy resin and other necessary additives are supplied to an extruder or the like with or without premixing, and 150 It is prepared by sufficiently melt-kneading in a temperature range of from ℃ to 350 ℃. In this case, for example, a single-screw extruder, twin-screw or tri-screw extruder equipped with a “unimelt” type screw, a kneader type kneader, etc. can be used. It is preferable to use by inserting several or no insertion elements.

  The thermoplastic resin composition of the present invention is excellent not only in flame retardancy but also in mechanical properties, heat resistance, retention stability and molding processability, and can be melt-molded. Therefore, extrusion molding, injection molding, and press molding are possible. It can be used after being formed into a film, a tube, a rod, or a molded product having any desired shape and size.

  The molded product comprising the flame retardant resin composition of the present invention obtained in this way makes use of its excellent flame retardancy, heat resistance, mechanical properties, molding processability, and transparency, etc. -It can be used for various applications such as electronic parts, automobile parts, mechanical mechanism parts, OA equipment, home appliances and other housings, and parts thereof.

  Specific examples of the molded product of the present invention include, for example, various covers, various gears, various cases, sensors, LED lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable capacitor cases, optical pickups, and oscillations. Child, terminal board, transformer, plug, printed wiring board, tuner, speaker, microphone, headphones, small motor, magnetic head base, power module, housing, semiconductor, liquid crystal, FDD carriage, FDD chassis, motor brush holder, parabolic Parts or housings such as antennas, computers, VTRs, televisions, irons, hair dryers, rice cookers, microwave ovens, audio equipments, audio equipment parts such as audio, laser discs, compact discs, etc. Homes such as jing, lighting, refrigerator, air conditioner, typewriter, word processor, office electrical product parts or housing, office computer related, telephone related, facsimile related, copier related parts or housing, cleaning jig, Various bearings such as oil-less bearings, stern bearings, underwater bearings, motor-related parts such as motor parts, lighters and typewriters, optical equipment such as microscopes, binoculars, cameras and watches, precision machine-related parts Or housing, alternator terminal, alternator connector, IC regulator, various valves such as exhaust gas valve, fuel-related / exhaust system / intake system pipes, air intake nozzle snorkel, intake manifold, fuel pump, engine coolant Int, carburetor main body, carburetor spacer, exhaust gas sensor, cooling water sensor, oil temperature sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter, thermostat base for air conditioner, heating hot air flow control valve Brush holders for radiator motors, water pump impellers, turbine vanes, wiper motor parts, dust distributors, starter switches, starter relays, transmission wire harnesses, window washer nozzles, air conditioner panel switch boards, coils for fuel-related solenoid valves , Fuse connector, horn terminal, electrical component insulation plate, step motor rotor, Lamp sockets, lamp reflectors, lamp housings, brake pistons, solenoid bobbins, engine oil filters, ignition device cases, and the like, which are extremely useful for these various applications.

Hereinafter, the configuration and effects of the present invention will be described in more detail with reference to Examples and Comparative Examples.
[Reference Example 1] (A-1) Method for Producing Graft Copolymer The following materials were charged in a polymerization vessel and heated to 65 ° C while stirring.
Polybutadiene (weight average particle diameter 0.2 μm): 50 parts by weight (in terms of solid content)
Potassium oleate: 0.5 parts by weight Glucose: 0.5 parts by weight Sodium pyrophosphate: 0.5 parts by weight Ferrous sulfate: 0.005 parts by weight Deionized water: 120 parts by weight.

  The polymerization was started when the internal temperature reached 65 ° C., and 50 parts by weight of a mixture consisting of 70 parts by weight of methyl methacrylate, 25 parts by weight of styrene, 5 parts by weight of acrylonitrile and 0.3 parts by weight of t-dodecyl mercaptan was taken over 5 hours. And continuously dropped. In parallel, an aqueous solution consisting of 0.25 parts by weight of cumene hydroperoxide, 2.5 parts by weight of potassium oleate and 25 parts by weight of pure water was continuously added dropwise over 7 hours to complete the reaction. The obtained graft copolymer latex was coagulated with sulfuric acid, neutralized with caustic soda, washed, filtered and dried to obtain (A-1-1) a graft copolymer.

  Acetone is added to a predetermined amount (m) of this (A-1-1) graft copolymer and refluxed for 4 hours. The solution is centrifuged at 8,800 rpm (centrifugal force 10,000 G) for 40 minutes, and then insoluble. The minute was filtered. This insoluble matter was dried under reduced pressure at 70 ° C. for 5 hours, then the weight (n) was measured, and the graft ratio = [(n) − (m) × L] / [(m) × L] × 100 was calculated. The grafting rate was 45%. Here, L is the rubber content of the graft copolymer.

  The filtrate of the acetone solution was concentrated with a rotary evaporator to obtain a precipitate (acetone soluble matter). This soluble matter was dried under reduced pressure at 70 ° C. for 5 hours, adjusted to 0.4 g / 100 ml (methyl ethyl ketone, 30 ° C.), and the intrinsic viscosity measured using an Ubbelohde viscometer was 0.26 dl / g.

  Further, in the same manner, by changing 70 parts by weight of methyl methacrylate, 25 parts by weight of styrene and 5 parts by weight of acrylonitrile to 70 parts by weight of styrene and 30 parts by weight of acrylonitrile, (A-1-2) graft copolymer Coalescence was obtained. The graft ratio at this time was 42%, and the intrinsic viscosity was 0.37 dl / g.

[Reference Example 2] (A-2) Production Method of Vinyl-Based Copolymer A stainless steel autoclave having a capacity of 20 L and equipped with a baffle and a foudra-type stirring blade is composed of 20% by weight methyl methacrylate and 80% by weight acrylamide. A solution obtained by dissolving 0.05 part of the copolymer in 165 parts of ion-exchanged water was stirred at 400 rpm, and the system was replaced with nitrogen gas. Next, the following mixed substances were added while stirring the reaction system, and the temperature was raised to 60 ° C. to initiate polymerization.
Methyl methacrylate: 70 parts by weight Styrene: 25 parts by weight Acrylonitrile: 5 parts by weight t-dodecyl mercaptan: 0.2 parts by weight 2,2′-azobisisobutyronitrile: 0.4 parts by weight

  After raising the reaction temperature to 65 ° C. over 15 minutes, the temperature was raised to 100 ° C. over 50 minutes. Thereafter, (A-2-1) vinyl copolymer was obtained by cooling the reaction system, separating the polymer, washing, and drying in accordance with ordinary methods. The intrinsic viscosity of this (A-2-1) vinyl copolymer was 0.35 dl / g.

  Further, in the same manner, by changing 70 parts by weight of methyl methacrylate, 25 parts by weight of styrene and 5 parts by weight of acrylonitrile to 70 parts by weight of styrene and 30 parts by weight of acrylonitrile, A polymer was obtained. The intrinsic viscosity of this (A-2-2) vinyl copolymer was 0.48 dl / g.

[Examples 1 to 4, Comparative Examples 1 to 9]
The formulation shown in Table 1 includes (A) the rubber-reinforced styrene-based resin and the following (B) adjacent flame retardant, (C) the epoxy resin and other necessary additives shown in Table 1 prepared in the above Reference Example. The mixture was mixed at a ratio, and a pellet-like polymer was produced by performing melt kneading and extrusion at 220 ° C. using a vented 30 mmφ twin-screw extruder (Ikegai Iron Works, PCM-30).

(B) Phosphorus flame retardant <B-1> Aromatic bisphosphate “PX-200” (manufactured by Daihachi Chemical Co., Ltd.) was used.
<B-2> Oligomer type aromatic bisphosphate “CR733S” (manufactured by Daihachi Chemical Co., Ltd.) was used.

(C) Epoxy resin (C-1) An epoxy resin “E-XLC-4L” (manufactured by Mitsui Chemicals) represented by the following formula (9) was used.
(C-2) An epoxy resin “NC-3000” (manufactured by Nippon Kayaku Co., Ltd.) represented by the following formula (10) was used.
(C-3) An epoxy resin “EPPN-201H” (manufactured by Nippon Kayaku Co., Ltd.) represented by the following formula (11) was used.
(C-4) An epoxy resin “EPPN-502H” (manufactured by Nippon Kayaku Co., Ltd.) represented by the following formula (12) was used.

(C-5) “Epicoat YL978” (manufactured by Yuka Shell Epoxy Co., Ltd.), which is a bisphenol A type epoxy resin, was used.

  Subsequently, each characteristic was evaluated with the following measuring methods about the test piece obtained by injection-molding on the conditions of molding temperature 230 degreeC and metal mold | die temperature 60 degreeC using Toshiba Machine IS55EPN injection molding machine.

[Flame retardance]:
About the test piece for flame retardance evaluation of 1.6 mm thickness obtained by injection molding, the flame retardance was evaluated about five test pieces according to the evaluation criteria defined in UL94. The flame retardancy level decreases in the order of V-0>V-1>V-2> HB.

[Impact resistance]:
Impact resistance was evaluated according to ASTM D256-56A.

[Heat-resistant]:
The heat resistance was evaluated according to ASTM D648 (load: 1.82 MPa).

[Light resistance]:
Using a xenon light resistance tester Ci35W type (manufactured by Atlas Co., Ltd.), irradiation was performed for 100 hours under the conditions of 55 ° C., 0.7 W / m ² and a filter (inside: quartz, outside: soda lime). The hue before and after irradiation was measured with a hue color difference meter (manufactured by Suga Test Instruments Co., Ltd.) to determine ΔΔE * (ΔE * after irradiation−ΔE * before irradiation). The smaller ΔΔE *, the better the light resistance.

[transparency]:
Using a direct reading haze meter manufactured by Toyo Seiki Co., Ltd., the total light transmittance value (%) and haze value of a 3 mm thick square plate were measured at 23 ° C. A higher total light transmittance value and a lower haze value indicate better transparency.

  Tables 1 and 2 show the measurement results of flame retardancy, impact resistance, heat resistance, light resistance, total light transmittance, and haze value of each sample.

  As is clear from the measurement results of Examples 1 to 4, the epoxy resin <C-1> and / or the phosphorus-based flame retardant <B-1> or <B-2> with respect to the rubber-reinforced styrene resin. By adding <C-2>, flame retardancy is improved, and a flame retardant resin composition having good impact resistance, heat resistance, light resistance, and transparency is obtained.

  On the other hand, when the content of the graft copolymer is too lower than the range of the present invention as in Comparative Example 1, the balance of physical properties is significantly impaired in terms of impact properties and molding processability. Further, as in Comparative Example 2, when a rubber-reinforced styrene resin having a refractive index outside a specific range is used, the total light transmittance is less than 60%, and the transparency is significantly impaired.

  Further, when no phosphorus flame retardant is added as in Comparative Example 3, no flame retardancy is exhibited, and when an excessive phosphorus flame retardant is added as in Comparative Example 4, the composition itself As a result, the brittleness of the resin becomes remarkable, and a good molded product cannot be obtained.

  When no epoxy resin is added as in Comparative Example 5, flame retardancy is not manifested, and when excess epoxy resin is added as in Comparative Example 6, the flame retardancy is improved, but rubber-reinforced styrene. Not only deteriorates the mechanical properties and heat resistance inherent to the resin, but also decreases transparency.

  Furthermore, as in Comparative Examples 7 to 9, when an epoxy resin deviating from the scope of the present invention is used, the flame retardancy is insufficient.

  It can be used for various applications such as electrical / electronic parts, automobile parts, mechanical mechanism parts, OA equipment, home appliances and other housings, and parts thereof.

Claims (4)

(A) 1 to 30 parts by weight of a phosphorus-based flame retardant and (C) 0.1 to 20 parts by weight of an epoxy resin represented by the following general formula (1) with respect to 100 parts by weight of rubber-reinforced styrene resin A flame retardant resin composition characterized in that the total light transmittance measured at 23 ° C. is 60% or more.

(In the above formula (1), X represents a group represented by the above general formula (2) or (3), and R1 to R9 are the same or different hydrogen atoms, alkyl groups having 1 to 8 carbon atoms, and aryl groups. (In addition, n represents an average value and is a value greater than 0 and 10 or less.) In the presence of 10 to 80 parts by weight of the rubber-reinforced polymer (A) rubber-reinforced styrene resin, (a) an unsaturated carboxylic acid alkyl ester monomer, (b) an aromatic vinyl monomer, (A-1) Graft copolymer obtained by copolymerizing 20 to 90 parts by weight of a monomer mixture comprising (c) vinyl cyanide monomer and (d) another vinyl monomer copolymerizable therewith. 10 to 100 parts by weight of a polymer, (a) an unsaturated carboxylic acid alkyl ester monomer, (b) an aromatic vinyl monomer, (c) a vinyl cyanide monomer, and (d) these The flame retardant resin composition according to claim 1, comprising 0 to 90 parts by weight of (A-2) vinyl copolymer composed of another copolymerizable vinyl monomer. The flame retardant resin composition according to claim 1 or 2, wherein the (B) phosphorus-based flame retardant is an aromatic phosphate represented by the following general formula (4).

(In the above formula (4), Ar ¹ , Ar ² , Ar ³ , Ar ⁴ represent the same or different phenyl groups or phenyl groups substituted with an organic residue containing no halogen atom. Y represents the above general formula. Represents a group represented by formula (5), (6) or (7), R ^{10 to} R ¹⁷ represent the same or different hydrogen atoms or alkyl groups having 1 to 5 carbon atoms, and Z represents a direct bond. , O, S, SO ₂ , C (CH ₃ ) ₂ , CH ₂ , CHPh, Ph represents a phenyl group, and n is an integer of 0 or more, and may be a mixture of different n. K and m are each an integer of 0 or more and 2 or less, and k + m is an integer of 0 or more and 2 or less.) A molded article comprising the flame retardant resin composition according to any one of claims 1 to 3.