WO1998012258A1

WO1998012258A1 - Flame-retardant styrenic resin composition

Info

Publication number: WO1998012258A1
Application number: PCT/JP1997/003181
Authority: WO
Inventors: Kazuyoshi Sueoka; Masanao Kawabe; Kiichi Kometani
Original assignee: Nippon Steel Chemical Co., Ltd.
Priority date: 1996-09-19
Filing date: 1997-09-10
Publication date: 1998-03-26

Abstract

A styrenic resin composition comprising 100 parts by weight of a resin composed mainly of a rubber-modified styrenic resin and 1 to 10 parts by weight of a flame retardant free from a halogen atom, wherein the rubber-modified styrenic resin satisfies the following requirements 1) to 6): 1) 3 wt.% ≤RC≤16 wt.% (wherein RC: rubber content); 2) 0.3≤Dw≤0.9 (wherein Dw: weight average particle diameter of dispersed rubber particles, νm); 3) 5 % value and 95 % value of cumulative particle diameter distribution on a weight basis of dispersed rubber particles are respectively not more than 1.0 νm and not less than 0.20 νm; 4) the weight ratio of the toluene insoluble to the rubber content is (1.0 to 2.5) : 1; 5) the proportion of particles having a salami-like structure in all the dispersed rubber particles is not less than 80 %; and 6) the proportion of dispersed rubber particles, wherein the number of styrenic resin particles enclosed in the dispersed rubber particles is not more than 20, is not less than 70 % of all the dispersed rubber particles.

Description

Description Flame retardant styrenic resin composition Technical field

The present invention relates to a flame-retardant styrenic resin composition, and more particularly, to a U.S. UL standard having improved printing and coating properties by adding a small amount of an organic phosphate compound without using a halogen-based flame retardant. The present invention relates to a flame-retardant styrene-based resin composition of a drip-after-ignition type which conforms to 9 4 V-2. Background art

Styrene resins are used in a wide variety of fields, including home appliances and office automation equipment, because of their excellent moldability, dimensional stability, impact resistance, rigidity, and electrical insulation. There is a high demand for flame retardancy in these application fields, and flame retardant resins occupy a large position. Various methods have been devised for imparting flame retardancy to flammable resins such as styrene resins, but halogen-based flame retardants such as bromine compounds having high flame-retardant effects are generally used. , And if necessary, a method of adding antimony oxide to the resin. However, when a halogen-based flame retardant is used, decomposition of the halogen compound during combustion may generate a large amount of gas harmful to the human body, which is an environmental problem.

Therefore, as a flame retarding method that generally does not use a halogen-based flame retardant, an organic phosphatile compound is added to a styrene-based resin or a resin composition comprising the same and a polyphenylene ether-based resin. A method for performing this is known in Japanese Patent Application Laid-Open No. 55-16081, Japanese Patent Application Laid-Open No. 57-30737, and the like. However, none of the techniques disclosed in these publications pays attention to the structural factors of rubber-modified styrenic resins suitable for imparting flame retardancy conforming to the standards of the United States UL Standard 94V-2. In a composition of a rubber-modified styrene resin containing or not containing polyphenylene diene ether-based resin and an organic phosphate-based compound, a relatively large amount of an organic phosphate-based compound is used. Must be added, which is a problem in terms of increasing the cost, lowering the heat-resistant temperature, and lowering the physical strength in industrial practice. Furthermore, the resin composition consisting of a styrene resin and a volifenylene ether resin has insufficient polarity, so if a thermal cycle test is performed, poor phenomena such as peeling of printing and coating due to insufficient adhesive strength will occur. There is also a problem that is easy to occur.

On the other hand, Japanese Patent Application Laid-Open No. 8-120152 discloses that a resin composition obtained by adding an organic phosphatic compound to a rubber-modified styrenic resin having a specific structural factor is obtained by adding a polyphenylene ether-based resin. It is disclosed that at least a large flame retardancy improving effect is exhibited. The publication discloses a rubber-modified styrene-based resin having a specific structural element that exhibits flame retardancy that meets the requirements of the United States UL Standard 94 V-2 when an organic phosphate-based compound is added. Use of force ^ Synergistically with flame retardants Printing · No mention is made of the structural factor of the rubber-modified styrenic resin that improves paintability. That is, the publication does not solve the problem of the decrease in printability and paintability, and was not satisfactory in terms of mechanical properties. As described above, the techniques disclosed in the past had various problems that had to be improved in industrial practice.

In view of such circumstances, the problem to be solved by the present invention is to provide a flame retardant which can melt and drip a flame from a molded article at the time of combustion and use a small amount of addition without using a halogen-based flame retardant. Provide flame-retardant styrene-based resin compositions that have flame retardancy conforming to U.S. UL standard 94 V-2 and that have improved heat resistance, mechanical properties, printability and paintability, etc. It is in. Disclosure of the invention

The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, a specific structure The inventors have found that the above-mentioned problems can be solved by using a rubber-modified styrene-based resin having a forming factor as an essential main component, and have completed the present invention.

That is, the flame-retardant styrenic resin composition of the present invention,

Component (A): A rubber-modified styrene-based resin occupies 50 to 100% by weight, and 100 parts by weight of the resin, and a component (B); A resin composition, wherein the rubber-modified styrene-based resin in the component (A) is in accordance with the following 1) to 6):

1) 3% by weight≤RC≤16% by weight (RC _: rubber content)

2) 0.3 ≤ Dw ≤ 0.9 (However _: weight average particle diameter of dispersed rubber particles (,

3) The 5% value of the weight-based cumulative particle size distribution of the dispersed rubber particles is 1. or less, the 95% value is 0.20 ini or more,

4) The ratio (weight) of the toluene insoluble matter to the rubber content is 1.0 to 2.5,

5) The proportion of particles having a salami structure in the total dispersed rubber particles is 80% or more,

6) The proportion of dispersed rubber particles in which the number of styrene resin particles included in the dispersed rubber particles is 20 or less is 70% or more of the total number of dispersed rubber particles,

Is satisfied.

In the present invention, the rubber-modified styrenic resin, which is the main component of the component (A), not only plays a role in maintaining the strength of the resin composition, but also acts synergistically with the component (B) to provide flame retardancy and printing. · A component that plays a role in imparting paintability. The component (B) is a component that imparts flame retardancy and printability / paintability to the component (A). As described above, in the present invention, the synergistic action of the component (A) and the component (B) having a specific structural factor is important. This synergistic action removes the flame from the article during combustion and produces an effective molten drop that can self-extinguish, resulting in compliance with U.S. UL Standard 94 V-2 with the addition of small amounts of phosphate compounds. It not only exhibits excellent flame retardancy, but also can exhibit high printing and painting properties. BEST MODE FOR CARRYING OUT THE INVENTION

The component (A) used in the present invention is a resin containing 50% by weight to 100% by weight of a rubber-modified styrene resin having a specific structural factor. In this case, the styrene-based resin containing no rubber component and the bolifenylene ether-based resin can be contained alone or in an arbitrary ratio of both, within a range of less than 50% by weight. Here, the rubber-modified styrenic resin used for the component (A) refers to a polymer in which a rubbery polymer is dispersed in a matrix in a matrix composed of an aromatic vinyl polymer. A monomer mixture obtained by adding an aromatic vinyl monomer and, if necessary, a vinyl monomer copolymerizable therewith in the presence of a rubber-like polymer, is subjected to a known bulk polymerization method and bulk suspension weight. It can be obtained by polymerization using a solution method, solution polymerization method, emulsion polymerization method or the like.

Here, examples of the aromatic vinyl monomer include styrene, methylstyrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, vinylethylbenzene, vinylxylene, and vinylnaphthalene. Vinyl monomers copolymerizable therewith include methyl methacrylate, ethyl methacrylate, methyl acrylate, methyl acrylate, acrylonitrile, methacrylonitrile, methacrylic acid, Examples include acrylic acid, maleic anhydride, phenyl maleimide, and a halogen-containing vinyl monomer. These copolymerizable monomers may be used singly or in combination of two or more types, but may be used for a wholly aromatic vinyl monomer including styrene. Usually, it is used in a proportion of 30% by weight or less, preferably 10% by weight or less.

Examples of the rubbery polymer used in the present invention include polybutadiene, styrene-butadiene copolymer, polyisoprene, butadiene-styrene-isoprene copolymer, and natural rubber. Regarding the microstructure of the polybutadiene portion, it may be a monocis polybutadiene rubber, a high cis polybutadiene rubber, or a mixture of a monocis polybutadiene rubber and a high cis polybutadiene rubber. Is also good. The structure of styrene-butadiene copolymer rubber is random Or a block type or a taper type. One of these rubbery polymers can be used alone, or two or more can be used in combination.

The content of the rubbery polymer in the rubber-modified styrenic resin of the present invention must be in the range of 3 to 16% by weight, preferably in the range of 7 to 15% by weight. . If it is less than 3% by weight, it will drip during combustion to form an effective molten drip that can remove flame from the molded article. Since the synergistic effect between component (A) and component (B) becomes small, In addition, a large amount of component (B) must be blended to achieve flame retardancy that meets the requirements of U.S. UL Standard 94 V-2, which is undesirable because it causes a decrease in heat resistance and mechanical properties. . If the content exceeds 16% by weight, the fluidity of the rubber-modified styrenic resin is remarkably deteriorated, so that it does not drop easily at the time of combustion, the component (B) must be incorporated in a large amount, and the cost rises. It is not preferable because the rigidity is reduced below a practical range.

The weight average particle diameter of the rubber-like polymer dispersed particles dispersed in the rubber-modified styrenic resin of the present invention needs to be in the range of 0.3 to 0.9 m, and 0.4 to 0.9 β It is preferably in the range of m. If the weight average particle diameter is less than 0.3 m, the impact resistance is insufficient. If it exceeds 0.9 m, the synergistic effect with the component (B) in flame retardancy and printability / paintability is reduced, and the gloss is reduced. Is also undesirably reduced.

In order to achieve the object of the present invention, the average particle size of the rubbery polymer dispersed in the rubber-modified styrenic resin is determined, and the cumulative percentage based on weight when accumulated from the larger one becomes 5% of the whole The particle diameter (5% value of the cumulative particle size distribution) is 1. O ^ m or less, preferably 0.9 m or less, and the particle size (95% of the cumulative particle Value) should be 0.20 or more, preferably 0.25 m or more. It is indispensable to keep the 5% value of the cumulative particle size distribution below 1.0 m in order to obtain excellent printability and paintability by synergistic effect with the component (B). Further, since the rubber polymer particles having a particle size of 0.211 or less cannot be expected to have an impact absorbing effect, if the 95% value is less than 0.20 / m, the impact resistance decreases. In addition, in order to obtain the target in the balance of physical properties between flame retardancy and mechanical strength, it is necessary to control the dispersed rubber-like polymer particles in the rubber-modified styrene-based resin to a specific dispersion form. That is, it is necessary that the rubber-like polymer dispersed particles have a salami structure. Here, the dispersed particles having a salami structure are rubber-based polymer dispersed particles in which two or more aromatic vinyl polymer particles are included in the dispersed particles. It is necessary that the ratio of the dispersed particles having the salami structure to the inside is 80% by weight or more. If the proportion of the dispersed particles having a salami structure is less than 80% by weight, the flame retardancy and impact resistance are reduced.

In addition, dispersed particles in which the number of particles of the aromatic vinyl polymer included in the dispersed particles of the rubber-like polymer of the rubber-modified styrenic resin is 20 or less are 70% or more of the total number of dispersed particles, Preferably, it should be at least 80%. If the number of particles of the contained aromatic monovinyl polymer is less than 20 or less than 70% of the total number of dispersed particles, the synergistic effect with the component (B) will be small, and printing and painting The property is extremely reduced. In addition, the glossiness (the sharpness of the reflected image) of the molded product visually decreases extremely. When the number of the dispersed particles containing 20 or less aromatic monovinyl polymers is 70% or more of the total number of the dispersed particles, the coloring property is improved. Here, the contained aromatic vinyl-based polymer particles are defined as the rubbery weight in a photograph taken by an electron micrograph of a rubber-modified styrene-based resin by an ultra-thin section method and magnified 1000 times. Among the aromatic monovinyl polymer particles included in the coalesced dispersion particles, it means particles having a minor axis of 0.3 mm, that is, 0.03 m or more on a photograph.

Furthermore, in the present invention, in order to satisfy the balance of flame retardancy, printing, paintability, impact resistance, rigidity, and physical properties, toluene insoluble content (X% by weight) contained in the rubber-modified styrene resin is required. And the ratio (X / Y) of the rubber component (Y weight%) must be in the range of 1.0 to 2.5, and preferably in the range of 1.2 to 2.0. When the content is in the above range, the coloring property is also improved. When X / Y is less than 1.0, flame retardancy * Impact resistance is significantly reduced, and when it is more than 2.5, printability, paintability and rigidity are greatly reduced. Therefore, a satisfactory physical property balance cannot be obtained.

The silicone oil represented by the following general formula (I) can be added to the rubber-modified styrenic resin of the present invention.

I I

-(S i-0) x- (S i-0) y- (I)

R ₂ R 4

(However, R, R ₂ , R ₃ , and R ₄ represent organic groups such as an alkyl group, an aryl group, and an aralkyl group.)

The silicone oil used here has a surface tension at 25 ° C of 19.0 to 22. Odyne / cra, preferably 19.8 to 21.5 dyne / cm, more preferably 20.1-21.2 dyne. It is preferably in the range of / cm. By adjusting the amount of silicon oil added and the surface tension within this range, the impact resistance can be improved. The viscosity of the silicone oil is not particularly limited, but is preferably 10 to 1000 centistokes at 25 ° C.

Examples of the silicon oil used in the present invention include dimethyl silicon oil, methyl phenyl silicon oil, methyl ethyl silicon oil, and hydroxyl, fluorine, alkoxy groups at the terminal or in the molecular chain of these silicon oils. Examples include silicone oil into which an amino group, an epoxy group, a carboxyl group, an amide group, an ester group, and a vinyl group are introduced. These silicon oils may be used alone or as a mixture of two or more. Further, the content of silicon oil in the rubber-modified styrenic resin is from 0.005 to 0.5% by weight, preferably from 0.005 to 0.3% by weight, more preferably from 0.005 to 0.2% by weight. Range.

In order to add silicone oil to the rubber-modified styrenic resin of the present invention, it can be added at any stage of the production process. For example, rubber-modified styrenic resin May be added to the raw material before the polymerization is carried out, may be added to the polymerization solution during the polymerization, or may be added in the granulation step after the completion of the polymerization. Or in a molding machine. As a method of adding after polymerization is completed, for example, a master pellet having a high silicon oil concentration is produced using silicon oil and a styrene-based resin or a rubber-modified styrene-based resin. A method of mixing resins may be used.

The method for producing the rubber-modified styrenic resin having the above-mentioned specific structural factor used in the present invention is not particularly limited. For example, a continuous bulk mounting method may be used, and a completely mixed reactor and a plurality of In a polymerization apparatus having a series of reactors arranged in series, the first complete mixing reactor polymerizes to the extent that the rubbery polymer does not turn into dispersed particles, and subsequently polymerizes in a plug flow polymerization reactor to form a rubbery polymer. A method of increasing the degree of polymerization while dispersing the polymer into dispersed particles can be employed.

The component (A) of the present invention comprises, in addition to the rubber-modified styrenic resin described above, at least one resin selected from a styrene-based resin containing no rubber component and a boriphenylene ether-based resin in total amount. To less than 50% by weight. Here, the styrene resin containing no rubber component includes polystyrene (GP), a homopolymer of styrene monomer, acrylonitrile-styrene copolymer (AS), and methyl methacrylate-styrene copolymer. Polymer (MS) and the like. In the present invention, the flowability of the flame-retardant resin composition can be easily adjusted by adding the styrene resin containing no rubber component to the component (II). The polyphenylene ether resin is a homopolymer or a copolymer having a unit represented by the following general formula (II).

(In the formula, Q and -Q ₄ are each independently selected from the group consisting of hydrogen and a hydrocarbon group, and m represents an integer of 30 or more.)

Specific examples of such polyfuylene ether resins include poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-dimethyl-1,4-phenylene) ether, and poly ( 2,6-dipropyl-1,4-phenylene ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly (2-methyl-1-6-propyl-1,1,4-phenyl) Len) ether, poly (2-ethyl-1-6-propyl-1,4-phenylene) ether, (2,6_dimethyl-1,4-phenylene) ether and (2,3,6-trimethyl) Copolymers of (1,4-phenylene) ether with (2,6-dimethyl-1,4-phenylene) ether and (2,3,6-trimethyl-1,4-phenylene) ether Copolymer of (2,6-dimethyl-1,4-phenylene) ether and (2,3,6-trie) Copolymers with butyl-1,4-phenylene) ether. Particularly, poly (2,6-dimethyl-1,4-phenylene) ether is preferred.

Reduced viscosity (0.5 gZd, a measure of the molecular weight of polyphenylene ether resin)

1, black hole form solution, measured at 30 ° C) is preferably in the range of 0.2 to 0.7 dlZg, and more preferably in the range of 3 to 0.6 d1 / g. . When the reduced viscosity of the polyolefin diene ether resin is within the above range, the balance between flame retardancy, moldability and mechanical properties is excellent. Rubber-Modified Styrene Resin z The preferred distribution ratio of other styrene-based resin / polyethylene nitrene ether-based resin is determined according to required mechanical strength, moldability, and heat resistance. Specifically, the content of the other styrene-based resin in the component (A) is less than 50% by weight, and more desirably less than 35% by weight. If the content is 50% by weight or more, the impact strength and Z or printing / paintability are undesirably reduced. Further, the content of the polyphenylene ether resin in the component (A) is within 20% by weight, and preferably within 15% by weight. When the content exceeds 20% by weight, the fluidity of the flame-retardant resin composition is reduced, so that the effect of the present invention is to drop by melting at the time of combustion, to remove the flame from the molded article and self-extinguish the flame. This is not preferable because it becomes extremely difficult.

Next, examples of the flame retardant containing no halogen atom which constitutes the component (B) of the present invention include flame retardants generally used in resins and rubbers, such as phosphorus-containing compounds, nitrogen-containing compounds, and inorganic metal compounds. These can be appropriately selected and used. Here, examples of the phosphorus-containing compound include an organic phosphorus-containing compound, red phosphorus, a phosphazene-based compound, and ammonium polyphosphate. Among them, examples of the organic phosphorus-containing compound include organic phosphates typified by triphenyl phosphite and organic phosphites typified by triphenyl phosphite. Compounds having at least one of the structural units represented by the following general formulas (ΙΠ) to (VI) are preferred.

0

! 1

R “(〇) _qi — P— (0) _{q 3} — R ₃ (HI)

(?

R z

(Hydrocarbon residue containing no where the R i R s are each halogen, ^, ~ 3 ₃ represents 0 or is.) R -co) _q- (IV)

(

(Wherein, R, a hydrocarbon residue containing no to R Masorezore halogen, hydrocarbon residue R ₅ to R ₈ do not contain hydrogen atoms or halogen, _1-0 ₆ 0 or 1, n is the degree of polymerization Indicates the number from 1 to 30.)

(V)

(Wherein, R have R _2, R _4, R ₅ does not contain halogen are hydrocarbon residue, R ₃ is _{_{- C (CH 3) 2 -}} , - CH 2 -, - S0 2 -, - CO- And Z or —0—, R _{6 to} R ₁₃ are a hydrogen atom or a halogen-free hydrocarbon residue, Q! To ci ₇ are 0 or 1, and n is a number having a degree of polymerization of 1 to 30.)

R Hiro (0 (VI)

(Wherein, RL to R ₆ each represent a hydrocarbon residue containing no halogen, R _{7 to} R ₉ represent a hydrogen atom or a hydrocarbon residue containing no halogen, and cn represents 0 or 1.) The phosphate system described above Specific examples of the compound are shown below, but the present invention is not limited thereto. For example, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, tris (2,6 —Dimethylphenyl) phosphate, bis (2,6-dimethylphenyl) phenyl phosphate, mono (2,6-dimethylphenyl) phosphate, bis (2,6-dimethylphenyl) 4-tert-butylphenyl phosphate , Bis (2,6-dimethylphenyl) 4-methylphenyl phosphate, bis (2,6-dimethylphenyl) 3-methylphenyl phosphate, bis (2,6-dimethylphenyl) 4-isopyrphenyl phosphate , Bis (2,6-dimethylphenyl) 2-isopyrphenylphosphitol, resorcinol bisphospho DOO, Bisufuenoru A Bisuhosufe DOO, human de Rokino Nbisuhosufe DOO, Application Benefits oxybenzene preparative Rihosufuwe one preparative etc. and these 混台 thereof. Preferably, it is at least one phosphatic compound selected from the group consisting of resorcinol bisphosphate, bisphenol-ru-A bisphosphat, hydroquinone bisphosphat, and trioxybenzentriphosphate.

These organic phosphorus-containing compounds may be used alone or in combination of two or more.

Examples of the nitrogen-containing compound as a flame retardant containing no halogen atom include melamine and melamine derivatives such as melamine cyanurate, melamine phosphate, and melamine borate.

Examples of the inorganic metal compound as a flame retardant containing no halogen atom include antimony trioxide, antimony tetroxide, antimony (colloidal) antimony, sodium antimonate and antimony phosphate such as antimony phosphate, and boric acid. Sub Examples include boric acid compounds such as lead and barium metaborate, molybdic acid compounds such as zinc molybdate and calcium molybdate, and metal hydroxides such as magnesium hydroxide.

When the component (B) is used in the present invention, the phosphorus-containing compound may be used alone, or two or more phosphorus-containing compounds and a nitrogen-containing compound or an inorganic metal compound may be used in combination. You can also. Among these components (B), an organic phosphate compound having a large synergistic effect with the component (A) is preferred in view of flame retardancy and printing / paintability. Particularly preferred examples are resorcin-bis (di-1,6-xylenyl phosphate), resorcin-bis (diphenyl phosphate), and triphenylphosphine in terms of printability, paintability and heat resistance. And bisphenol-A-bis (dicresyl phosphate).

The feature of the present invention is that the use of the component (B) enhances the flame retardancy of the composition due to a synergistic effect with the component (A) having a specific structural factor, and provides a high flame retardancy with a low flame retardant addition amount. It not only achieves the level, but also achieves high printability and paintability. That is, according to the present invention, a resin that imparts excellent flame retardancy without impairing the original performance and characteristics of the styrenic resin material (A) component, and further provides the above-described high-level printing and coating performance A composition can be obtained.

The organic phosphate compound used in the present invention can be produced by a known method. For example, a suitable phenol and Z or a polyhydric phenol can be reacted with a phosphorylating agent. Examples of the phosphorylating agent include phosphorus oxychloride and phosphorus pentachloride. The phosphorylation reaction can be performed in the presence of a catalyst such as aluminum chloride or magnesium chloride, or in the presence of an organic base such as pyridine. The phosphates can also be prepared by reacting sodium salts of phenols and / or polyhydric phenols with phosphorylating agents or by oxidizing the corresponding phosphites by known methods. In the present invention, the amount of the component (B) is 1 to 10 parts by weight based on 100 parts by weight of the component (A). It must be parts by weight. It is preferably from 2 to 7 parts by weight, more preferably from 3 to 7 parts by weight. If the amount of the component (B) is less than 1 part by weight, the effect of flame retardation of the resin cannot be achieved, which is not preferable. On the other hand, if the amount of the component (B) is more than 10 parts by weight, not only the inherent properties of the resin are lost, but also the cost increases and the heat resistance decreases.

In the present invention, a lubricant may be added to the resin composition comprising the component (A) and the component (B), if desired, to further enhance the synergistic effect of the component (A) and the component (B). . That is, by adding a lubricant, the dispersibility of the component (B) is improved while improving the fluidity of the resin composition comprising the components (A) and (B), thereby improving printing, coating properties and flame retardancy. Can be further improved. Examples of such lubricants that can be used in the present invention include polyolefin-based lubricants, metal stone-based lubricants, fatty acid ester-based lubricants, alcohol-based lubricants, fatty acid-based lubricants, polysiloxane-based lubricants, aromatic compound oligomers, and liquid paraffin. And mixtures thereof. The amount of the lubricant to be added is generally 10 parts by weight or less, preferably 5 parts by weight or less, based on 100 parts by weight of the component (A). If the amount of the lubricant exceeds 10 parts by weight, it is not preferable because the inherent properties of the resin are lost.

A thermoplastic resin and a thermosetting resin other than those described above can be added to the flame-retardant styrenic resin composition of the present invention, if desired, as long as the effects of the present invention are not impaired. Also, if necessary, ordinary additives, such as antistatic agents, antioxidants, UV absorbers, coloring agents, surface modifiers, dispersants, metal lithography, organotin compounds, light stabilizers, processing Auxiliary agents, foaming agents, inorganic fillers such as glass fiber and talc can be added. Specific examples of the flame-retardant styrenic resin composition comprising the above-mentioned components (A) and (B) in the present invention The production method is not particularly limited, but can be produced by a usual method, for example, a melt blend by kneading using an extruder. The resin composition of the present invention thus obtained is used with molding materials such as telephones, facsimile machines, housings for OA equipment, etc., which conform to the U.S. UL standard 94V-2. By using, for example, injection molding, extrusion molding or compression molding, a molded article excellent in required flame retardancy, mechanical properties and appearance characteristics can be obtained.

Example

Hereinafter, Examples and Comparative Examples which are embodiments of the present invention will be specifically described, but the present invention is not limited to these Examples and Comparative Examples. The examples and comparative examples of the present invention were evaluated based on the following evaluation method.

(1) toluene-insoluble matter

After dissolving a fixed amount (1 g) of the rubber-modified styrene resin in toluene (30 ml), sediment it by centrifugation, remove the supernatant, and separate the insoluble matter. After drying the insoluble matter to remove toluene, determine the weight of the insoluble matter.

Toluene-insoluble matter (% by weight) = (weight of toluene-insoluble matter / weight of resin) × l 00

(2) Rubber content

It was determined by the method of the disc.

(3) Measurement of 5% value and 95% value of rubber particle size distribution and cumulative particle size distribution

Resin is stained with osmium tetroxide, and electron micrographs are taken by ultra-thin section method. _{C In} a photograph magnified 10,000 times, particle diameters of 1000 or more dispersed rubber particles are measured, and the average particle diameter is determined by the following formula.

Average particle size = ∑ 11,0 ÷ ∑n ₁ D, ³

(Where n i is the number of rubbery polymer particles of particle diameter D)

In addition, the rubber particles are accumulated from the larger one, and the particle diameter at which the cumulative ratio on a weight basis is 5% of the total is 5% of the cumulative particle diameter distribution, and the particle diameter at which 95% is obtained is 9 δ of the cumulative particle diameter distribution.

% Value.

(4) Izod impact value

It was measured at 23 ° C by a method according to ASTM-D256 (V notch, 1Z4 inch test piece).

(5) Deflection temperature under load (DTUL) It was measured by a method according to AS TM-D 648 (1Z4 inch test piece).

(6) Melt flow rate (MF R)

The measurement was performed at 200 ° C and 5 kgf by a method according to ASTM-D246.

(7) Flammability

Evaluate according to the thickness of the test piece (1Z8 inch, 1Z12 inch and 1Z16 inch) by VB (Vertical Burning) method and HB (Horizontal Burning) method according to UL-94. V0, VI, V2 and HB grades were determined.

(8) Printing and paintability

Printing and paintability were evaluated based on the strength of the adhesion of silk screen printing after the thermal cycle test. First, silk screen printing was performed on a 16 mm × 16 mm × 3 mm plate made by injection molding using a printing ink for polystyrene, dried at 90 ° C for 1 hour, and then dried at room temperature for 1 hour. I left it. Thus created test piece 23 ^D C, placed in a 60 RH% (relative humidity) a humidistat which are set to the condition, after 1. the retention time in this condition, the 5 ° CZ min The temperature was reduced to 140 ° C at a rapid rate. After holding at 40 ° C for 2 hours, the temperature was raised to 60 ° C at a rate of 5 ° C / min. After maintaining at 60 ° C for 2 hours, the temperature was lowered to 23 at a rate of 5 ° C / min.

Then, the test piece was taken out from the constant temperature / humidity chamber, and then a grid-like scratch was made on the printing surface of this flat plate with a cutter, and a cellophane tape was applied. Thereafter, the printed surface was peeled off at once at an angle of 45 ° from the surface to evaluate the peeling state of the printed surface with an optical microscope and visually.

A: No peeling of the printed surface occurs.

〇: The printed surface does not peel off, but the peeling slightly occurs on the cutting edge by the cutter o

Δ: The printed surface slightly peels off. X: The printed surface peels over a wide area.

(9) Colorability

The coloring property was evaluated by visually observing the coloring property of a molded article obtained by adding 1 part by weight of a dark blue colorant to 100 parts by weight of the resin composition, and judging based on the following criteria.

：: Vivid dark blue color.

〇: dark blue.

Δ: Dark blue color with a slight whitish color.

X: Whiteish navy blue

(10) gloss

It was determined in accordance with JIS K7105.

(1 1) Image brightness

It was determined in accordance with JIS K7105.

Reference Example 1: Production of rubber-modified styrenic resin (HIPS-1-7)

To 100 parts by weight of a mixed solution of styrene and polybutadiene rubber, 20 parts by weight of ethylbenzene was added, and the raw material solution dissolved was added at a constant supply rate (22 parts by volume / hr). It is continuously supplied to a complete mixing tank type reactor (25 volumes by volume), heated and polymerized, and then a second plug-type reactor (60 volumes) with a stirrer. Was continuously charged in its entirety to carry out polymerization. At the outlet of the first reactor, the rubbery polymer has not yet been dispersed into particles, and as a result of polymerization while stirring in the second reactor, the polymerization liquid is dispersed at the outlet of the second reactor. The particle formation was completed.

Next, the entire amount of the above-mentioned polymerization solution was continuously charged into a third reactor comprising a plug flow type reactor (20 volume parts), and polymerization was continued. After the removal, the pellets were removed.

According to the above method, the average particle size of the rubber-like polymer dispersed particles is 0.30 ^ m to 1.0 μm, and the ratio of the toluene-insoluble component to the rubber component is in the range of 1.5 to 2.4 7 Kind of go Thus, a modified styrene resin was obtained. 0.05% by weight of silicone oil having a surface tension of 20.9 dyne / cm was added to the obtained rubber-modified styrenic resin, and the mixture was kneaded with an extruder. The rubber-modified styrenic resin (HIPS-1 to 7) used in the above was obtained as a pellet.

Reference Example-2: Production of rubber-modified styrenic resin (HIPS-8)

A 100% by weight mixture of styrene and polybutadiene rubber was added with 15 parts by weight of ethylbenzene, and the solution was dissolved at a constant feed rate (22 parts by volume / hr). It is continuously supplied to a tower-type plug-flow reactor (30 volume parts internal volume), heated and polymerized, and then the second reactor (60) is a tower-type plug-flow reactor with a stirrer. (Volume part), and the whole amount was continuously charged to carry out polymerization. Next, the entire amount of the above-mentioned polymerization solution was continuously charged into a third reactor (20 volume parts by volume) composed of a plug flow type reactor to continue polymerization, and the polymerization solution was evaporated under reduced pressure to remove volatile components. After removal, it was pelletized.

By the above method, a rubber-modified styrene resin having an average particle diameter of the rubber-like polymer dispersed particles of 0.601 and a ratio of a toluene component to a rubber component of 2.8 was obtained. The same silicone oil as in Reference Example 1 was added to the obtained rubber-modified styrene-based resin and kneaded with an extruder to obtain a rubber-modified styrene-based resin as shown in Table 1 used in Comparative Examples of the present invention.

(HIPS-8) was obtained.

Reference Example 1: Production of rubber-modified styrene resin (HIPS-9)

A rubber-modified styrene resin with an average particle diameter of 0.28 zm and a core-shell structure, obtained by polymerizing a styrene monomer with stirring in the presence of a styrene-butadiene block copolymer, has a surface tension of 20. A mixture of 9 dyne / cm silicone oil and 0.05% by weight of HIPS-3 obtained in Reference Example 11 was kneaded with an extruder to reduce the proportion of rubber particles having a salami structure to 52%. Thus, a rubber-modified styrene resin (HIPS-9) as shown in Table 1 was obtained.

Example 1 (A) 100 parts by weight of HIPS-1 as a component, (B) 4.0 parts by weight of resorcin-bis (di-2,6-xylenylphosphate) (phosphoryl_1) as a component, 1.0 part by weight of liquid paraffin (Lubricant-1) was blended as another component, and kneaded at a kneading temperature of 200 ° C using a 3 Omm02 screw extruder manufactured by Nippon Steel Works, Ltd. The obtained composition was evaluated for Izod impact value, DTUL, MFR, print / paintability, colorability, gloss, and image clarity. Table 2 shows the results.

Examples 2 to 16 and Comparative Examples 1 to 8

The same experiment as in Example 1 was repeated, except that the type of the rubber-modified styrenic resin (HIPS-2 to 9) and the type and amount of Z or the flame retardant and the lubricant were changed as follows. Tables 2 to 5 show the results.

Phosphate-1: Resorcin-bis (diphenylphosphate)

Phosphate-1 3: Triphenyl phosphate

Phosphate 4: Bisphenol-A-bis (dicresyl phosphate) Lubricant 1: Ethylene bisstearyl amide

Lubricant 1: Stearyl stearate

Note that NR in Tables 2 and 3 is an abbreviation of ot Rated, which means that the standard does not reach V-2.

Types of HIPS HIPS1 HIPS2 HIPS3 HIPS4 HIPS5 HIPs6 HIPs7 HIPs8 HIPs 9

¾J product i |) rubber ft Yes 1 3. 2 1 4.5 1 1. 5 9.2 1 2. 5 1 0.0 1 2. 0 1 3.0 1 2. 8

¥ Average rubber grain r- ½ (^ m) 0.59 0.43 0.64 0.70 0.30 1.00 0.7.5 0.60 0.3 0.3% distribution of 5% ω (.um) 0.75 0.62 0.82 0.95 0.45 1.50 1.1 0 0.95 0.82

'¾ 子 ¾' 95% of the cloth (m) 0.29 0.25 0.33 0.35 0.1 7 0.60 0.20 0.30 0.15

Lj (%) of comb abalone 96 90 95 97 8 8 98 90 96 5 2 Non-toluene component 1 Rubber composition 2.0 1.6 1.5 2.1 1.8 2.2 2.4 2.8 2.3 Included PS 2 Q pcs: lower (%) 94 88 8 3 90 90 65 7 4 87 93 Silicone Oinore ^ J 'dyne / cm) 20.9 20.9 20.9 20. 9 2 0. 9 20.9 20. 9 20. 9 20. 9 Silicone oil added ίιί (,!,!: 96) 0.05 0.05 0.05 0.05 0.05 0.05 0.05.0.0 5 0.05 0.05 Zot S ¾r Strong kg (kgf * cai / cni) 13.8 10.5 0.513.0 11.5 3.013.0 12.0 12.5 6.4

Table 2

Fue Example-1 Implemented Ryuichi 2 Example-3 Implemented ^-4 Ratio ¾ί Column 1 2

H I P S H I P S -1 H I P S -2 H I P S-3 Η [P S -4 H [P S -5 Η t P S -6

Addition of HIPS 100 parts by weight 100 parts by weight 100 parts by weight 100 parts by weight 100 parts by weight 100 parts by weight ffi part Flame retardantt'-to-1 phosphor 1 phos 7-to-1 * 4 parts by weight 4 parts by weight 4 Far parts 4 parts by weight 4 parts fi part 4 ffifi part Lubricant Lubricant-1 Lubricant-1 Lubricant-1 Lubricant-1 Lubricant-1 Lubricant-1 Lubricant Addition 1 Lubricant Part by weight 1 part by weight 1 SS part 1 ¾ 虽 part 1 S3 part Flammability (UL-94 1/8 "thickness) V-2 V-2 V-2 V-2 NR. R. Flammability (U-94 1 6 "thickness) V-2 V-2 V-2 V-2 NRNR Eye impact value (kgf ♦ cm / cm) 10. 2 9. 4 1 1. 0 8. 8 2. 5 7.2

D T U L (° C) 80 80 8 1 82 7 4 72

MFR (g / lOmin) 4. 9 1 2. 0 5. 6 6. 2 4. 5 1 6. 9 Printing and coating properties ◎ ◎ ◎ ◎ Amm Colorability ◎ ◎ ◎ ◎ Δ Δ %) 100 1 01 1 00 99 1 0 1 86 Image sharpness (! ¾) 90 95 84 8 3 95 42

Table 3

Comparative Example-3 Comparative Example-4 Comparative Example-5

HIP SHIPS-7H! P S -8 H I P S -9

Addition of HIPS Λ lOOffl part 100 parts by weight 100 IE parts tl Fuel-g-1.7 l-g-1 phos 7 g-1 m Addition amount of fuel 4 parts S-part Lubricant-1 Lubricant-1 Lubricant-1 Lubricant Addition amount lffi part 1 a_ part 1 part by weight Flammability (UL-94, 1/8 "thick) NRNRNR Flammability (U-94, 186" thick) NRNRNR Lightweight impact value (kgf-CE / cai) 1 0.2.9.4.4.3

DTUL CO 80 80 81

MFR (g / lOmin) 5. 3 4. 3 5. 6 Printing and coating properties Δ Δ Coloring properties Δ Δ Δ Hikarizawa (%) 98 98 99 Image W Brightness (%) 5 1 8 1 9 1

Table 4

¾ 5

Industrial applicability

According to the present invention, a small amount of flame retardant conforms to UL standard 94 V-2 of a melt-dropping type, has excellent heat resistance, mechanical properties, fluidity, and printability A styrene-based resin composition can be obtained, and this resin composition having excellent economic effects can be widely used for housings of OA equipment and other mechanical parts.

Claims

The scope of the claims

1. Component (A): Rubber-modified styrenic resin is 50 to 100% by weight.

Component (B): 1 to 10 parts by weight of a flame retardant containing no halogen atom

A styrene-based resin composition comprising the rubber-modified styrene-based resin in the above component (A), wherein the rubber-modified styrene-based resin has the following requirements 1) to 6)

1) 3% by weight ≤ RC 16% by weight (RC: rubber content)

. 2) 0. 3≤Dw≤0 9 (where _Dw: Weight average particle diameter of the dispersed rubber particles [,

3) The 5% value of the weight-based cumulative particle size distribution of the dispersed rubber particles is 1.0 / ra or less, the 95% value is 0.20 ^ ra or more,

A flame-retardant styrenic resin composition characterized by satisfying the following.

2. The component (A) comprises, in addition to the rubber-modified styrene resin, at least one resin selected from styrene-based resins and polyphenylene ether-based resins containing no rubber. 2. The flame-retardant styrenic resin composition according to 1.

3. The flame-retardant styrenic resin composition according to claim 1, wherein the component (B) is an organic phosphate compound.

4. The flame-retardant styrene according to claim 3, wherein the organic phosphine compound is at least one selected from organic phosphite compounds represented by the following general formulas (III) and (IV). -Based resin composition. RL— (〇) ■ (〇) R (III)

) _n „

R ₂

(Wherein, R! To R ₃ is a hydrocarbon residue containing no halogen respectively, _qi to q ₃ is 0 or is 1.)

(Wherein, R! To R hydrocarbon residues do not each contain halogen ₄ hydrocarbon residue R ₅ to R ₈ do not contain hydrogen atoms or halogen, q! Qs is 0 or 1, n is the degree of polymerization Indicates the number from 1 to 30.)

5. The flame-retardant styrenic resin composition according to claim 1, wherein 10 parts by weight or less of a lubricant is added to 100 parts by weight of the component (A).

6. The flame-retardant styrenic resin composition according to claim 1, wherein the component (B) is resorcin-bis (di-1,2,6-quinrenyl phosphite X).