JP2014122283A - Flame-retardant thermoplastic resin composition and resin molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant thermoplastic resin composition excellent in not only fire resistance, but also weather resistance, shock resistance, flowability and color development.SOLUTION: A flame-retardant thermoplastic resin composition is manufactured by blending a fire retardant (C) to a resin composition containing a graft copolymer (A) and a copolymer (B). The graft copolymer (A) is obtained by graft polymerizing an aromatic vinyl-based monomer, vinyl cyanide monomer-based monomer, and other vinyl-based monomer which can be copolymerized therewith to a diene-based rubber-like polymer. The copolymer (B) is obtained by copolymerizing the aromatic vinyl-based monomer and the vinyl cyanide-based monomer.

Description

  The present invention relates to a flame retardant thermoplastic resin composition excellent not only in flame retardancy but also in weather resistance, impact resistance, fluidity and color developability, and a molded article obtained from the resin composition.

  ABS resin is a resin with an excellent balance between impact resistance and workability, and is used in a wide range of fields such as interior and exterior parts for vehicles such as automobiles, housings for various home appliances and OA equipment, and other miscellaneous goods. . However, the ABS resin has a disadvantage that the weather resistance is inferior because the butadiene rubber polymer used as the rubber component is easily decomposed by ultraviolet rays or the like. Then, the ASA resin which improved the weather resistance by substituting the rubber component in ABS resin for acrylic rubber is put into practical use. However, although ASA resin is excellent in weather resistance, it has a disadvantage that it is inferior in impact resistance and color development.

  In addition, ASA resin is flammable, and the demand for flame retardancy is increasing due to safety issues, and various flame retarding techniques have been proposed. Patent Document 1 uses a rubber-reinforced styrene-based resin, an organic phosphorus compound, and a composite rubber-based graft copolymer as a thermoplastic resin composition with improved flame retardancy, impact resistance, light resistance, and moldability. Flame retardant thermoplastic resin compositions have been proposed. However, there is a problem that the color developability is insufficient.

JP 2000-212385 A

  An object of the present invention is to provide a graft copolymer constituting a flame retardant thermoplastic resin composition excellent not only in flame retardancy but also in weather resistance, impact resistance, fluidity and color developability, and the graft copolymer. It is in providing the flame-retardant thermoplastic resin composition used.

  As a result of diligent studies to solve the problems of the prior art, the present inventors have found that a composite rubber having a specific polymer configuration includes a single monomer such as a vinyl cyanide monomer or an aromatic vinyl monomer. The inventors have found that the above object can be achieved by using a graft copolymer obtained by polymerizing a body mixture, and have reached the present invention.

  That is, the present invention is a flame retardant thermoplastic in which 1 to 40 parts by weight of a flame retardant (C) is blended with 100 parts by weight of a resin composition containing a graft copolymer (A) and a copolymer (B). It is a resin composition, and the graft copolymer (A) is a composite rubber composed of 5 to 50% by weight of a conjugated diene rubbery polymer and 50 to 95% by weight of a crosslinked acrylate polymer. 20 to 90 parts by weight of at least one monomer selected from aromatic vinyl monomers, vinyl cyanide monomers and other vinyl monomers copolymerizable therewith With respect to the composite rubber obtained by polymerization and existing in the graft copolymer, the number of particles of the composite rubber having a circle equivalent particle diameter of 150 nm or less is 50% or less of the total composite rubber particles. A polymer, a copolymer (B) It is a copolymer obtained by copolymerizing an aromatic vinyl monomer, a vinyl cyanide monomer, and other vinyl monomers that can be copolymerized if necessary. The present invention relates to a flame retardant thermoplastic resin composition and a resin molded product obtained from the resin composition.

  According to the present invention, a graft copolymer constituting a flame retardant thermoplastic resin composition excellent in not only flame retardancy but also weather resistance, impact resistance, fluidity and color developability and the graft copolymer are used. A flame retardant thermoplastic resin composition can be provided.

The present invention will be described in detail below.
The flame retardant thermoplastic resin composition of the present invention contains 1 to 40 parts by weight of the flame retardant (C) with respect to 100 parts by weight of the resin composition containing the graft copolymer (A) and the copolymer (B). The flame retardant thermoplastic resin composition.

  The graft copolymer (A) used in the present invention comprises an aromatic vinyl monomer, cyanide in the presence of a composite rubber composed of a conjugated diene rubber-like polymer and a crosslinked acrylate ester polymer. A graft copolymer obtained by graft polymerization of at least one monomer selected from vinyl monomers and other vinyl monomers copolymerizable therewith.

  Examples of the conjugated diene rubber-like polymer constituting the composite rubber used in the present invention include polybutadiene rubber, styrene-butadiene rubber (SBR), styrene-butadiene-styrene (SBS) block copolymer, and styrene- (ethylene-butadiene). -Styrene (SEBS) block copolymer, acrylonitrile-butadiene rubber (NBR), methyl methacrylate-butadiene rubber. In particular, polybutadiene rubber and styrene-butadiene rubber are preferable.

  Although there is no restriction | limiting in particular in the weight average particle diameter of the conjugated diene type rubber-like polymer which comprises a composite rubber, From a viewpoint of a physical-property balance, it is preferable that it is 0.1-1.0 micrometer, 0.2-0.5 micrometer. It is more preferable that The weight average particle diameter of the conjugated diene rubber-like polymer can be adjusted by a known method, but the purpose is to produce a conjugated diene rubber-like polymer having a relatively small particle diameter in advance and agglomerate it. It is also possible to use an agglomerated enlarged conjugated diene rubbery polymer having a weight average particle diameter of

  The crosslinked acrylate polymer constituting the composite rubber used in the present invention is an acrylate monomer having an alkyl group having 1 to 16 carbon atoms in the presence of a crosslinking agent, such as methyl acrylate or ethyl acrylate. , Butyl acrylate, 2-ethylhexyl acrylate, or the like, or, if necessary, other copolymerizable monomers such as styrene, acrylonitrile, methyl methacrylate, etc. The resulting polymer.

  Examples of the crosslinking agent used in the crosslinked acrylic acid ester polymer constituting the composite rubber include divinylbenzene, allyl (meth) acrylate, ethylene glycol di (meth) acrylate, diallyl phthalate, dicyclopentadiene di (meth) acrylate, Trimethylolpropane tri (meth) acrylate, pentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, triallyl cyanurate, triallyl isocyanurate Etc.

  The composite rubber used in the present invention can be obtained by emulsion polymerization of a monomer (mixture) constituting a crosslinked acrylate polymer in the presence of a conjugated diene rubber-like polymer. That is, the composite rubber of the present invention has a core-shell structure in which the conjugated diene rubber-like polymer is the core and the crosslinked acrylate polymer is the shell.

  The ratio of the conjugated diene rubbery polymer to the crosslinked acrylate polymer constituting the composite rubber used in the present invention is 5 to 50% by weight of the conjugated diene rubbery polymer, and the crosslinked acrylate polymer weight. The blend needs to be 50 to 95% by weight, but the conjugated diene rubber-like polymer is preferably 7 to 40% by weight, more preferably 10 to 30% by weight from the viewpoint of balance of physical properties. .

  The composite rubber used in the present invention is a conjugated diene rubber-like polymer core as described above, and is characterized by having a core-shell structure in which the cross-linked acrylate polymer is a shell. Not all acrylate-based polymers are polymerized into conjugated diene rubber-like polymers, and some may exist as single particles of crosslinked acrylate-based polymers. Thereafter, the conjugated diene rubber-like polymer and the cross-linked acrylic acid ester polymer include not only the composite rubber having a core-shell structure but also the cross-linked acrylic acid ester polymer present alone. Even so, it is called composite rubber.

  In the present invention, regarding the composite rubber present in the graft copolymer (A), the number of composite rubber particles having an equivalent circle particle diameter of 150 nm or less needs to be 50% or less of the total composite rubber particles. If the number of particles of the composite rubber having an equivalent circle particle diameter of 150 nm or less is more than 50%, the resulting thermoplastic resin composition is inferior in impact resistance and flame retardancy. The number of particles having a circle-equivalent particle diameter of 150 nm or less is preferably 40% or less, and more preferably 20% or less.

  The composite rubber present in the graft copolymer (A) and having an equivalent circle particle diameter of 150 nm or less is often a single particle of the above-mentioned crosslinked acrylate polymer, and the single particle is thermoplastic. This is a main factor that adversely affects the impact resistance and flame retardancy of the resin composition. Therefore, in order to reduce particles having an equivalent circle particle diameter of 150 nm or less, it is necessary to prevent the generation of single particles of a crosslinked acrylate ester polymer as much as possible during the production of the composite rubber.

  Further, even if the composite rubber having a core-shell structure has an adverse effect on impact resistance and flame retardancy as long as the equivalent-circle particle diameter is 150 nm or less, the present invention provides a crosslinked acrylate polymer. With respect to the composite rubber containing single particles, the number of particles having an equivalent circle particle size of 150 nm or less is required to be 50% or less.

  Any method may be used as a method of not producing single particles of the crosslinked acrylic ester polymer at the time of polymerization of the composite rubber used in the present invention. For example, a method of changing an emulsifier amount, a monomer addition rate, etc. It is done.

  When polymerizing the composite rubber, the polymerization initiator used is a water-soluble polymerization initiator such as potassium persulfate, sodium persulfate, ammonium persulfate, cumene hydroperoxide, benzoyl peroxide, t-butyl hydroperoxide, acetyl Oil-soluble polymerization initiators such as peroxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide can be appropriately used. Furthermore, specific examples of the reducing agent preferably used include ferrous sulfate heptahydrate, sulfite, bisulfite, pyrosulfite, nitrite, nithionate, thiosulfate, formaldehyde sulfonate, Examples thereof include benzaldehyde sulfonate, carboxylic acids such as L-ascorbic acid, tartaric acid and citric acid, further reducing sugars such as lactose, dextrose and saccharose, and amines such as dimethylaniline and triethanolamine. Examples of the chelating agent include tetrasodium pyrophosphate and sodium ethylenediaminetetraacetate.

  As the emulsifier used when polymerizing the composite rubber, carboxylate, sulfate, sulfonate and the like can be used as appropriate. Furthermore, specific examples of emulsifiers preferably used include potassium oleate, dipotassium alkenyl succinate, sodium rosinate, sodium dodecylbenzenesulfonate, and the like.

  The gel content in the toluene solvent of the composite rubber used in the present invention is not particularly limited, but from the viewpoint of physical properties balance, the gel content of the composite rubber is preferably 90% or more, and 95% or more. It is more preferable.

  The graft copolymer (A) used in the present invention includes an aromatic vinyl monomer, a vinyl cyanide monomer, and other vinyls copolymerizable with these in the presence of the above composite rubber. It is a graft copolymer obtained by graft polymerization of at least one monomer selected from the system monomers.

  The graft copolymer (A) needs to contain 10 to 80 parts by weight of composite rubber in 100 parts by weight of the graft copolymer. If the composite rubber is less than 10 parts by weight, the impact resistance is poor, and if it exceeds 80 parts by weight, the fluidity is poor. The content of the composite rubber is preferably 30 to 70 parts by weight, and more preferably 40 to 60 parts by weight.

  Examples of the aromatic vinyl monomer constituting the graft copolymer (A) include styrene, α-methylstyrene, paramethylstyrene, bromostyrene, and the like, and one or more of them can be used. In particular, styrene and α-methylstyrene are preferable.

  Examples of the vinyl cyanide monomer constituting the graft copolymer (A) include acrylonitrile, methacrylonitrile, ethacrylonitrile, fumaronitrile and the like, and one or more of them can be used. Particularly preferred is acrylonitrile.

  Examples of other copolymerizable vinyl monomers constituting the graft copolymer (A) include (meth) acrylic acid ester monomers, maleimide monomers, amide monomers, and the like. 1 type, or 2 or more types can be used. (Meth) acrylic acid ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl acrylate, (meth) acrylic Examples include phenyl acid, 4-t-butylphenyl (meth) acrylate, (di) bromophenyl (meth) acrylic acid, chlorophenyl (meth) acrylate, and the maleimide monomer includes N-phenylmaleimide, N-cyclohexylmaleimide and the like can be exemplified, and examples of the amide monomer include acrylamide and methacrylamide.

  The composition ratio of the above-mentioned monomer graft-polymerized with the composite rubber is not particularly limited, but 60 to 90% by weight of aromatic vinyl monomer, 10 to 40% by weight of vinyl cyanide monomer, and copolymerizable Other vinyl monomer composition ratio of 0 to 30% by weight, aromatic vinyl monomer 30 to 80% by weight, (meth) acrylic acid ester monomer 20 to 70% by weight and copolymerizable Composition ratio of other vinyl monomers 0 to 50% by weight, aromatic vinyl monomers 20 to 70% by weight, (meth) acrylic acid ester monomers 20 to 70% by weight, vinyl cyanide monomer The composition ratio is preferably 10 to 60% by weight of the monomer and 0 to 30% by weight of another copolymerizable vinyl monomer.

  There is no restriction | limiting in particular in the method for superposing | polymerizing a graft copolymer (A), An emulsion polymerization method, suspension polymerization method, block polymerization method, etc. can be used. When the emulsion polymerization method is used, a latex of the graft copolymer (A) can be obtained by graft polymerization of the above-described monomer to the above-described composite rubber. The latex of the graft copolymer (A) is coagulated by a known method, and the powder of the graft copolymer (A) can be obtained through washing, dehydration, and drying steps.

  Graft ratio of graft copolymer (A) (determined from the amount of acetone soluble and insoluble components of the graft copolymer and the weight of the composite rubber of the graft copolymer), and the reduced viscosity of acetone soluble component (0.4 g) / 100 cc, N, N dimethylformamide solution measured at 30 ° C.) and any structure can be used depending on the required performance, but from the viewpoint of balance of physical properties, the graft ratio is 5 to 150%. The reduced viscosity is preferably 0.2 to 2.0 dl / g.

  The copolymer (B) used in the present invention is a copolymer of an aromatic vinyl monomer, a vinyl cyanide monomer, and other vinyl monomers that can be copolymerized as required. However, as each monomer constituting the copolymer (B), the same monomers as those used in the graft copolymer (A) can be used.

  The flame retardant thermoplastic resin composition of the present invention is characterized by containing a graft copolymer (A) and a copolymer (B), and the graft copolymer (A) and the copolymer (B) The composition ratio is not particularly limited and can be set to a desired composition ratio depending on the desired physical properties, but the physical property is that the content of the composite rubber in the flame-retardant thermoplastic resin composition is 3 to 50% by weight. From the viewpoint of balance, it is preferably 10 to 30% by weight.

  As the flame retardant (C) used in the present invention, a known flame retardant corresponding to the required flame retardant level can be appropriately used. For example, phosphorus compounds such as red phosphorus, polyphosphates, phosphate esters and phosphazenes, halogen compounds such as halogenated aromatic triazines and halogenated epoxy resins, silicone resins such as silicone resins, polyalkylsiloxanes and polyalkylphenylsiloxanes Compounds, nitrogen-containing compounds such as melamine, cyanuric acid and melamine cyanurate, metal oxides such as antimony oxide, bismuth oxide, zinc oxide and tin oxide, inorganic compounds such as aluminum hydroxide and magnesium hydroxide, other carbon fibers and glasses Examples thereof include fibers and expanded graphite. In particular, a phosphate ester flame retardant having a weight average molecular weight of 327 or more represented by the following chemical formula 1, a halogenated aromatic triazine compound represented by the following chemical formula 2, Use of halogenated organic compounds represented Preferably, they may be mixed these one or more.

(R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom or a monovalent organic group, but at least one of R ₁ , R ₂ , R ₃ and R ₄ is A monovalent organic group, X is a divalent organic group, k, l, m and n are each independently 0 or 1, and N is an integer of 0 to 10.

  In the above chemical formula 1, the monovalent organic group includes an optionally substituted alkyl group, aryl group, and cycloalkyl group. Examples of the substituent in the substituted case include an alkyl group, an alkoxy group, and an alkylthio group. , Aryl groups, aryloxy groups, arylthio groups, etc., and combinations of these substituents (arylalkoxyalkyl groups, etc.), or combinations of these substituents bonded by oxygen, sulfur, nitrogen atoms, etc. A group (such as an arylsulfonylaryl group) may be a substituent. Examples of the divalent organic group include an alkylene group, a phenylene group which may have a substituent, a polyhydric phenol, and a group derived from a polynuclear phenol (such as bisphenol). Particularly preferred divalent organic groups include hydroquinone, resorcinol, diphenylolmethane, diphenyloldimethylmethane, dihydroxydiphenyl, p, p'-dihydroxydiphenylsulfone, dihydroxynaphthalene and the like. These can be used alone or in combination of two or more.

  Specific examples of these phosphate ester flame retardants include tricresyl phosphate, trixylenyl phosphate, hydroxyphenyl diphenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, and various condensed phosphate esters. It is done.

(R1, R2, and R3 represent different or the same kind of halogenated alkyl group having 1 to 20 carbon atoms, halogenated aryl group, or halogenated alkylaryl group.)

  Although the usage-amount of a flame retardant (C) is decided according to a required flame retardance level, it is 1-40 with respect to a total of 100 weight part of a graft copolymer (A) and a copolymer (B). Parts by weight. If it is less than 1 part by weight, the necessary flame retardant effect is not exhibited. On the other hand, if it exceeds 40 parts by weight, the physical properties of the resin composition will be significantly reduced. From the viewpoint of flame retardancy and physical property balance, the amount is preferably 2 to 35 parts by weight, and more preferably 5 to 30 parts by weight.

  In addition, a flame retardant aid can be used in combination to enhance the flame retardant effect. Preferred flame retardant aids are compounds and oxides containing elements belonging to Group 15 in the Periodic Table of Elements, and specifically include nitrogen-containing compounds, phosphorus-containing compounds, antimony oxide, bismuth oxide, iron oxide, Metal oxides such as zinc oxide and tin oxide are also effective. Among these, a particularly preferred flame retardant aid is antimony oxide, and specific examples include antimony trioxide and antimony pentoxide. These flame retardant aids may be those subjected to surface treatment for the purpose of improving dispersion in the resin and for improving the thermal stability of the resin. The amount of the flame retardant aid used is preferably 0.5 to 20 parts by weight with respect to 100 parts by weight of the total of the graft copolymer (A) and the copolymer (B), and preferably 1 to 10 parts by weight. More preferably.

  The flame-retardant thermoplastic resin composition of the present invention includes hindered amine-based light stabilizers, hindered phenol-based, sulfur-containing organic compound-based, phosphorus-containing organic compound-based antioxidants, phenol-based, acrylate as necessary. -Based heat stabilizers, benzoate-based, benzotriazole-based, benzophenone-based, salicylate-based UV absorbers, organic nickel-based lubricants such as higher fatty acid amides, plasticizers such as phosphate esters, odor masking agents, carbon Black, titanium oxide, pigments, dyes, and the like can also be added. Furthermore, reinforcing agents and fillers such as talc, calcium carbonate, aluminum hydroxide, glass fiber, glass flake, glass bead, carbon fiber, and metal fiber can be added.

  The flame-retardant thermoplastic resin composition of the present invention can be obtained by mixing the above-described components. In order to mix, well-known kneading apparatuses, such as an extruder, a roll, a Banbury mixer, a kneader, can be used, for example.

  The flame-retardant thermoplastic resin composition of the present invention can be used by mixing with other thermoplastic resins within a range not impairing the purpose. Examples of such other thermoplastic resins include polycarbonate resins such as polycarbonate, acrylic resins such as polymethyl methacrylate, polybutylene terephthalate resins, polyethylene terephthalate resins, polyester resins such as polylactic acid, and polyamide resins. Can be used.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” and “%” are based on weight.

Production of small particle size styrene-butadiene rubber latex After replacing the inside of a 10 liter pressure vessel with nitrogen, 95 parts by weight of 1,3-butadiene, 5 parts by weight of styrene, 0.5 parts by weight of n-dodecyl mercaptan, potassium persulfate 0.3 parts by weight, disproportionated sodium rosinate 1.8 parts by weight, sodium hydroxide 0.1 parts by weight, and deionized water 145 parts by weight were charged and reacted at 70 ° C. for 8 hours with stirring. Thereafter, 0.2 parts by weight of disproportionated sodium rosinate, 0.1 parts by weight of sodium hydroxide and 5 parts by weight of deionized water were added. Further, stirring was continued for 6 hours while maintaining the temperature at 70 ° C. to complete the reaction. Thereafter, the remaining 1,3-butadiene was removed under reduced pressure to obtain a styrene-butadiene rubber latex. The obtained styrene-butadiene rubber latex was dyed with osmium tetroxide (OsO ₄ ), dried, and photographed with a transmission electron microscope. Using an image analysis processor (apparatus name: IP-1000PC manufactured by Asahi Kasei Co., Ltd.), the area of 1000 rubber particles was measured, the circle equivalent diameter (diameter) was determined, and the weight average particle diameter of styrene-butadiene rubber As a result, the weight average particle size was 120 nm.

Production of agglomerated styrene-butadiene rubber latex 270 parts by weight of the styrene-butadiene rubber latex obtained above and 0.1 part by weight of sodium dodecylbenzenesulfonate were added to a 10-liter pressure vessel and stirred for 10 minutes. Thereafter, 20 parts by weight of 5% aqueous phosphoric acid solution was added over 10 minutes. Subsequently, 10 parts by weight of a 10% aqueous potassium hydroxide solution was added to obtain an agglomerated styrene-butadiene rubber latex (1).
As a result of calculating the weight average particle diameter of the agglomerated styrene-butadiene rubber by the above-described method, the weight average particle diameter was 330 nm.

To a 10 liter pressure vessel, 270 parts by weight of the styrene-butadiene rubber latex obtained above and 0.3 parts by weight of sodium dodecylbenzenesulfonate were added and stirred and mixed for 10 minutes, and then 20 parts by weight of 5% aqueous phosphoric acid solution. Was added over 10 minutes. Next, 10 parts by weight of a 10% aqueous potassium hydroxide solution was added to obtain an agglomerated styrene-butadiene rubber latex (2).
As a result of calculating the weight average particle size of the agglomerated styrene-butadiene rubber by the above-mentioned method, the weight average particle size was 250 nm.

Production of cross-linked butyl acrylate rubber latex In a nitrogen-replaced glass reactor, 180 parts by weight of deionized water, 15 parts by weight of butyl acrylate, 0.1 parts by weight of allyl methacrylate, 0.16 parts by weight of dipotassium alkenyl succinate (in terms of solid content) ), 0.15 part by weight of potassium persulfate was added and reacted at 65 ° C. for 1 hour. Thereafter, an emulsifier aqueous solution in which 0.64 parts by weight of dipotassium alkenyl succinate (in terms of solid content) was dissolved in 85 parts by weight of butyl acrylate and 0.53 parts by weight of allyl methacrylate and 20 parts by weight of deionized water was added for 3 hours. Over time. After dripping, it was kept for 3 hours to obtain a crosslinked butyl acrylate rubber latex.

The weight average particle diameter of the obtained crosslinked butyl acrylate rubber latex was calculated by the method described below. Graft copolymerization was performed using 15 parts (solid content) of the obtained crosslinked butyl acrylate rubber latex, 64 parts of styrene, and 21 parts of acrylonitrile to obtain a graft copolymer. The graft copolymer powder was melt-kneaded to obtain pellets. From the obtained pellet, an ultrathin section was cut out at −85 ° C. using a cryomicrotome, stained with ruthenium tetroxide (RuO ₄ ), and photographed with a transmission electron microscope (JEM-1400: manufactured by JEOL Ltd.). I took a picture. Using an image analyzer (Asahi Kasei IP-1000PC), the area of 1000 cross-linked butyl acrylate rubber particles was measured, the equivalent circle diameter (diameter) was determined, and the weight average particle diameter of the cross-linked butyl acrylate rubber latex was calculated. As a result, the weight average particle size was 200 nm.

Manufacture of composite rubber latex (a-1) A 10 L glass reactor is charged with 20 parts by weight (solid content) of the above-mentioned agglomerated styrene-butadiene rubber latex (1) and 160 parts by weight of deionized water, and nitrogen replacement is performed. went. After nitrogen substitution, when the temperature in the tank reached 45 ° C., 0.2 parts by weight of glucose, 0.03 part by weight of anhydrous sodium pyrophosphate and 0.001 part by weight of ferrous sulfate were added to 20 parts by weight of deionized water. Dissolved aqueous solution was added. Furthermore, 20 parts by weight of butyl acrylate and 0.1 parts by weight of allyl methacrylate were added. An aqueous solution in which 0.9 part by weight of dipotassium alkenyl succinate and 0.1 part by weight of tertiary butyl hydroperoxide are dissolved in 25 parts by weight of deionized water after the temperature in the tank reaches 50 ° C. 60 parts by weight of butyl acrylate and 0.4 parts by weight of allyl methacrylate were continuously added dropwise over 5 hours. After dropping, the mixture was held for 3 hours to obtain a composite rubber latex (a-1) composed of an enlarged styrene-butadiene rubber and a crosslinked butyl acrylate polymer.

Manufacture of composite rubber latex (a-2) A 10-liter glass reactor is charged with 20 parts by weight (solid content) of the above-mentioned agglomerated styrene-butadiene rubber latex (2) and 160 parts by weight of deionized water, and nitrogen replacement is performed. went. After nitrogen substitution, when the temperature in the tank reached 45 ° C., 0.2 parts by weight of glucose, 0.03 part by weight of anhydrous sodium pyrophosphate and 0.001 part by weight of ferrous sulfate were added to 20 parts by weight of deionized water. Dissolved aqueous solution was added. Furthermore, 20 parts by weight of butyl acrylate and 0.1 parts by weight of allyl methacrylate were added. An aqueous solution in which 0.9 part by weight of dipotassium alkenyl succinate and 0.1 part by weight of tertiary butyl hydroperoxide are dissolved in 25 parts by weight of deionized water after the temperature in the tank reaches 50 ° C. 60 parts by weight of butyl acrylate and 0.4 parts by weight of allyl methacrylate were continuously added dropwise over 5 hours. After dropping, the mixture was held for 3 hours to obtain a composite rubber latex (a-2) composed of an enlarged styrene-butadiene rubber and a crosslinked butyl acrylate polymer.

Manufacture of composite rubber latex (a-3) A 10 L glass reactor was charged with 20 parts by weight (solid content) of the above-mentioned agglomerated styrene-butadiene rubber latex (1) and 160 parts by weight of deionized water, followed by nitrogen substitution. It was. After nitrogen substitution, when the temperature in the tank reached 45 ° C., 0.2 parts by weight of glucose, 0.03 part by weight of anhydrous sodium pyrophosphate and 0.001 part by weight of ferrous sulfate were added to 20 parts by weight of deionized water. Dissolved aqueous solution was added. Furthermore, 5% of an emulsifier solution prepared by dissolving 0.9 parts by weight of dipotassium alkenyl succinate and 0.1 parts by weight of tertiary butyl hydroperoxide in 25 parts by weight of deionized water, 16 parts by weight of butyl acrylate, 0% of allyl methacrylate .1 part by weight was added, and after the temperature in the tank reached 50 ° C., it was kept for 1 hour. It was dripped continuously. After dripping, it hold | maintained for 3 hours and obtained composite rubber latex (a-3) comprised from enlarged styrene-butadiene rubber and a crosslinked butyl acrylate polymer.

Manufacture of composite rubber latex (a-4) Into a 10 L glass reactor, 20 parts by weight (solid content) of the above-mentioned agglomerated styrene-butadiene rubber latex (1) and 160 parts by weight of deionized water were charged and replaced with nitrogen. It was. After nitrogen substitution, when the temperature in the tank reached 45 ° C., 0.2 parts by weight of glucose, 0.03 part by weight of anhydrous sodium pyrophosphate and 0.001 part by weight of ferrous sulfate were added to 20 parts by weight of deionized water. Dissolved aqueous solution was added. Furthermore, 20% of an emulsifier solution obtained by dissolving 0.9 parts by weight of dipotassium alkenyl succinate and 0.1 parts by weight of tertiary butyl hydroperoxide in 25 parts by weight of deionized water, 16 parts by weight of butyl acrylate, 0% of allyl methacrylate .1 part by weight was added, and the temperature in the tank reached 50 ° C., and held for 1 hour. The remaining emulsifier solution, 64 parts by weight of butyl acrylate, and 0.4 parts by weight of allyl methacrylate were added over 5 hours. It was dripped continuously. After dropping, the mixture was held for 3 hours to obtain a composite rubber latex (a-4) composed of an enlarged styrene-butadiene rubber and a crosslinked butyl acrylate polymer.

Manufacture of composite rubber latex (a-5) A 10 L glass reactor was charged with 20 parts by weight (solid content) of the above-mentioned agglomerated styrene-butadiene rubber latex (1) and 160 parts by weight of deionized water, followed by nitrogen substitution. It was. After nitrogen substitution, when the temperature in the tank reached 45 ° C., 0.2 parts by weight of glucose, 0.03 part by weight of anhydrous sodium pyrophosphate and 0.001 part by weight of ferrous sulfate were added to 20 parts by weight of deionized water. Dissolved aqueous solution was added. Furthermore, 40% of an emulsifier solution obtained by dissolving 0.9 parts by weight of dipotassium alkenyl succinate and 0.1 parts by weight of tertiary butyl hydroperoxide in 25 parts by weight of deionized water, 16 parts by weight of butyl acrylate, 0% of allyl methacrylate .1 part by weight was added, and the temperature in the tank reached 50 ° C., and held for 1 hour. The remaining emulsifier solution, 64 parts by weight of butyl acrylate, and 0.4 parts by weight of allyl methacrylate were added over 5 hours. It was dripped continuously. After dropping, the mixture was held for 3 hours to obtain a composite rubber latex (a-5) composed of an enlarged styrene-butadiene rubber and a crosslinked butyl acrylate polymer.

Production of Graft Copolymer (A-1) Into a glass reactor, 60 parts by weight (solid content) of the composite rubber latex (a-1) was charged and nitrogen substitution was performed. After nitrogen substitution, when the temperature inside the tank reached 60 ° C., 0.2 part by weight of glucose, 0.1 part by weight of anhydrous sodium pyrophosphate and 0.005 part by weight of ferrous sulfate were added by 10 parts by weight of deionized water. An aqueous solution dissolved in was added. After reaching 65 ° C., a mixture of 12 parts by weight of acrylonitrile, 28 parts by weight of styrene, 0.1 part by weight of tertiary decyl mercaptan, 0.3 part by weight of cumene hydroperoxide and 20 parts by weight of deionized water was mixed with potassium oleate. An aqueous emulsifier solution in which 0 part by weight was dissolved was continuously added dropwise over 5 hours. After dropping, the mixture was held for 3 hours to obtain a graft copolymer latex (A-1). Thereafter, salting out, dehydration, and drying were performed to obtain a powder of the graft polymer (A-1).

Production of Graft Copolymers (A-2) to (A-5) Graft copolymers (A- 1) except that the composite rubber latex (a-1) was changed to the composite rubber latex (a-2) to (a-5). It manufactured like A-1) and obtained graft copolymer latex (A-2)-(A-5). Thereafter, salting out, dehydration and drying were performed to obtain powders of graft polymers (A-2) to (A-5).

Production of Graft Copolymer (A-6) A glass reactor was charged with 60 parts by weight of the agglomerated and enlarged styrene-butadiene rubber latex (1) in terms of solid content, and was purged with nitrogen. After nitrogen substitution, when the temperature inside the tank reached 60 ° C., 0.2 part by weight of glucose, 0.1 part by weight of anhydrous sodium pyrophosphate and 0.005 part by weight of ferrous sulfate were added by 10 parts by weight of deionized water. After adding the aqueous solution dissolved in the solution, the temperature was raised to 65 ° C. Thereafter, 12 parts by weight of acrylonitrile, 28 parts by weight of styrene, 0.1 part of tertiary decyl mercaptan, 0.3 part by weight of cumene hydroperoxide and 20 parts by weight of deionized water were added with 1.0 part by weight of potassium oleate. The dissolved aqueous emulsifier solution was continuously added dropwise over 4 hours. After dropping, the mixture was held for 3 hours to obtain a graft copolymer latex (A-6). Thereafter, salting out, dehydration, and drying were performed to obtain a graft polymer (A-6) powder.

Production of Graft Copolymer (A-7) A glass reactor was charged with 15 parts by weight of a coagulated and enlarged styrene-butadiene rubber latex (1) in terms of solid content and 45 parts by weight of a crosslinked butyl acrylate rubber latex in terms of solid content. Nitrogen replacement was performed. After nitrogen substitution, when the temperature inside the tank reached 60 ° C., 0.2 part by weight of glucose, 0.1 part by weight of anhydrous sodium pyrophosphate and 0.005 part by weight of ferrous sulfate were added by 10 parts by weight of deionized water. After adding the aqueous solution dissolved in the solution, the temperature was raised to 65 ° C. Thereafter, 12 parts by weight of acrylonitrile, 28 parts by weight of styrene, 0.1 part of tertiary decyl mercaptan, 0.3 part by weight of cumene hydroperoxide and 20 parts by weight of deionized water were added with 1.0 part by weight of potassium oleate. The dissolved aqueous emulsifier solution was continuously added dropwise over 4 hours. After dropping, the mixture was held for 3 hours to obtain a graft copolymer latex (A-7). Thereafter, salting-out, dehydration and drying were performed to obtain a graft polymer (A-7) powder.

Production of copolymer (B) A copolymer (B) comprising 70 parts by weight of styrene and 30 parts by weight of acrylonitrile was obtained by a known bulk polymerization method. As a result of measuring the reduced viscosity of the obtained copolymer (B) by the above method, the reduced viscosity was 0.60 dl / g.

Flame retardant (C)
C-1: condensed phosphate ester (PX-200, manufactured by Daihachi Chemical Industry Co., Ltd.)
C-2: condensed phosphate ester (CR-741, manufactured by Daihachi Chemical Industry Co., Ltd.)
C-3: 2,4,6-tris (2,4,6-tribromophenoxy) -1,3,5-triazine (SR-245, manufactured by Dai-ichi FRF Co., Ltd., melting point 232 ° C., bromine content (Weight 67%)
C-4: Brominated modified epoxy resin (Puratherm EP-16 manufactured by DIC Corporation, softening point 116 ° C., bromine content 50% by weight)
C-5: Brominated modified epoxy resin (Puratherm EC-20 manufactured by DIC Corporation, softening point 115 ° C., bromine content 56% by weight)
C-6: Tetrabromobisphenol A (SAYTEX CP-2000, Albemarle Japan Co., Ltd., melting point 181 ° C., bromine content 59% by weight)

Additive (D)
Flame retardant aid: Patox-M (antimony trioxide) manufactured by Nippon Seiko Co., Ltd.
Light stabilizer: ADEKA Corporation ADK STAB LA77Y
UV absorber: Sumitomo 200 manufactured by Sumitomo Chemical Co., Ltd.

<Examples 1-9 and Comparative Examples 1-5>
After mixing the graft copolymer (A), copolymer (B), flame retardant (C) and additive (D) in the proportions shown in Table 1, melt at 240 ° C. using a 40 mm twin screw extruder. It knead | mixed and the pellet of the flame-retardant thermoplastic resin composition was obtained. Various molded articles were molded using the obtained pellets, and physical properties were evaluated. The evaluation results are shown in Table 1. In addition, each evaluation method is shown below.

The obtained pellet was cut out at a low temperature of −85 ° C. using a cryomicrotome to obtain an ultrathin section. The obtained ultrathin sections were stained with ruthenium tetroxide (RuO ₄ ), and observed and photographed using a transmission electron microscope (JEM-1400: manufactured by JEOL Ltd.). The area of 1000 particles was measured using an image analysis apparatus (Asahi Kasei IP-1000PC), and the equivalent circle diameter (diameter) was determined to calculate the ratio of the number of composite rubber particles having a diameter of 150 nm or less.

Impact Resistance Various test pieces were molded according to ISO test method 294 using the pellets obtained in each Example and Comparative Example, and impact resistance was measured.
The impact resistance was in conformity with ISO 179, and a Charpy impact value with a notch was measured at a thickness of 4 mm. Unit: kJ / m ²

The pellets obtained in Examples and Comparative Examples fluidity, in compliance with ISO 1133, 220 ° C., was measured melt volume flow rate under the condition of 10kg load. Unit; ^cm 3/10 minutes

For evaluation of color developability, molding was performed with an injection molding machine (J-150EP, cylinder temperature: 230 ° C., mold temperature: 60 ° C., manufactured by Nippon Steel Works) using the pellets obtained in each example and comparative example. The formed product (60 mm × 60 mm × 2 mm) was used. The hue difference between the white background and the black background of the molded product obtained by hue measurement according to JIS-Z8729 was used as a measure of the color developability of the molded product (the larger the value, the better the color developability). The spectrophotometer used was CMS-35SP manufactured by Murakami Color Research Co., Ltd.

Weather resistance Colored pellets by mixing 1 part of titanium oxide (RTC-30) with 100 parts of pellets obtained in each Example and Comparative Example, and melt-kneading at 240 ° C using a 40 mm single screw extruder Got. Using the colored pellets, a molded product (90 mm × 55 mm × 2.5 mm) molded by an injection molding machine (Yamagi Seiki Seisakusho SAV-30-30 cylinder temperature: 210 ° C. mold temperature: 50 ° C.) was obtained. . Using the resulting molded product, an accelerated exposure test was conducted for 200 hours under conditions of 63 ° C and rain using a Sunshine Super Long Life Weather Meter, WEL-SUN-HCH-B manufactured by Suga Test Instruments Co., Ltd. It was. Thereafter, weather resistance was evaluated by measuring a color difference (ΔE) before and after exposure using a colorimeter.

Using the pellets obtained in each of the flame retardant Examples and Comparative Examples, a test piece having a thickness of 1.6 mm was prepared according to the UL94 standard. Flame retardancy was evaluated by performing a flammability test using the obtained test piece.

  As shown in Table 1, Examples 1 to 9 are examples of the flame retardant thermoplastic resin composition according to the present invention, and are excellent not only in flame retardancy but also in weather resistance, impact resistance, fluidity and color development. It was.

  As shown in Table 1, Comparative Examples 1 and 2 were inferior in impact resistance and weather resistance because the number of particles of the composite rubber having a circle equivalent particle diameter of 150 nm or less exceeded 50%. Moreover, since the comparative example 3 uses ABS resin as a graft copolymer, it was inferior to the weather resistance. In Comparative Example 4, the conjugated diene rubber-like polymer and the acrylate ester polymer were not present as the composite rubber, and thus the color developability and weather resistance were inferior. Comparative Example 5 was inferior in flame retardancy because the amount of flame retardant used was small.

  The flame-retardant thermoplastic resin composition of the present invention is excellent not only in flame retardancy but also in weather resistance, impact resistance, fluidity and color development, so that it can be used for exterior parts for vehicles and products used outdoors. High value.

Claims (2)

  A flame-retardant thermoplastic resin composition comprising 1 to 40 parts by weight of a flame retardant (C) based on 100 parts by weight of a resin composition containing a graft copolymer (A) and a copolymer (B). The graft copolymer (A) is an aromatic vinyl compound containing 10 to 80 parts by weight of a composite rubber composed of 5 to 50% by weight of a conjugated diene rubbery polymer and 50 to 95% by weight of a crosslinked acrylate polymer. Graft obtained by graft polymerization of 20 to 90 parts by weight of at least one monomer selected from a vinyl monomer, a vinyl cyanide monomer and other vinyl monomers copolymerizable therewith The number of particles of the composite rubber having a circle equivalent particle diameter of 150 nm or less with respect to the composite rubber existing in the graft copolymer is 50% or less of the total composite rubber particles. A polymer, a copolymer ( ) Is a copolymer obtained by copolymerizing aromatic vinyl monomers, vinyl cyanide monomers, and other vinyl monomers that can be copolymerized if necessary. A flame-retardant thermoplastic resin composition.   A resin molded product obtained by molding the flame retardant thermoplastic resin composition according to claim 1.