JP2000230093A - Flame-retardant resin composition and molding made therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition excellent in impact resistance, heat resistance, fluidity, and light resistance by compounding a polystyrene resin with an aromatic phosphate and a silicone rubber and/or a silicone resin each having a specified or lower heating loss in air in a specified ratio. SOLUTION: This composition is prepared by compounding 100 pts.wt. polystyrene resin with 1-30 pts.wt. aromatic phosphate represented by formula I with 0.2-4 pts.wt. silicone rubber and/or silicone resin each having a heating loss of at most 50 wt.% at 800 deg.C in a heating test (rate of temperature rise of 40 deg.C/min) in air and desirably containing a silica filler. In the formula, R1 to R8 are each H or a 1-5C alkyl; Ar1 to Ar4 are each phenyl or a phenyl substituted with a halogen-free organic group; X is a group of any one of formulae II to IV; Y is a direct bond, O, S, SO2, C(CH3)2, CH2, or CHPh; Ph is phenyl; n is 0 or greater; k and m are each 0-2; and k+m=0-2. This composition is useful for electrical and electronic components, automotive components, machine components, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having excellent flame retardancy, impact resistance, heat resistance, fluidity and light resistance without impairing the original mechanical properties of the thermoplastic resin. .

[0002]

2. Description of the Related Art Plastics have excellent mechanical properties,
Due to its moldability and electrical insulation, it is used in a wide range of fields including home electric appliances, OA appliances, automobiles and other parts. However, most of plastics are flammable, and various techniques have been proposed for flame retardancy due to safety issues.

[0003] Generally, a method is employed in which a halogen-based flame retardant such as a bromine compound having a high flame-retardant efficiency and antimony oxide are blended with a resin to make the resin flame-retardant. However,
This method has problems such as a large amount of smoke generated during combustion.

[0004] Therefore, in order to overcome these drawbacks of halogen-based flame retardants, a flame-retardant resin containing no halogen has been strongly desired in recent years.

[0005] As a method of making a thermoplastic resin flame-retardant without using a chlorine or bromine-based flame retardant, ammonium polyphosphate and pentaerythritol are added to a rubber-reinforced polystyrene resin.
A method of blending a polyhydroxy compound such as benzene and a silane coupling agent (JP-A-5-140412),
A method of blending a melamine-coated ammonium polyphosphate and a specific nitrogen-containing organic compound with a thermoplastic resin (JP-A-6-34)
No. 0815) and a method of blending a small amount of a phenol resin and a flame retardant in a thermoplastic resin (Japanese Patent Application Laid-Open No. 7-53879).

[0006]

Problems to be Solved by the Invention
The composition described in Japanese Patent Publication No. 2 cannot obtain sufficient flame retardancy, and furthermore, when the mechanical properties are reduced or a polyhydric alcohol compound is used, mold contamination during molding or stickiness due to moisture absorption of the molded product occurs. Had problems. Also, JP-A-6-3408
No. 15 has a problem that sufficient flame retardancy cannot be obtained. Further, the composition described in JP-A-7-53879 has an effect of improving the flame retardancy in the flame retardancy evaluation specified in UL-94, but the test area such as a square plate has a small burning area and drip behavior. Therefore, there is a problem that sufficient flame retardancy cannot be obtained, and the flame retardancy varies depending on the test piece shape. Further, when a phenol resin is used, there are also problems such as coloring after dry heat treatment and light resistance being remarkably impaired.

[0007] The present invention solves the above-mentioned problems, and at the same time imparts high flame retardancy to a polystyrene resin, is excellent in impact resistance, heat resistance, fluidity, and light resistance and does not discolor even after dry heat treatment. The purpose is to provide things.

[0008]

Means for Solving the Problems According to the present invention, as a result of intensive studies to solve the above-mentioned problems, when a specific phosphorus compound and a silicone compound are used in combination with a polystyrene resin,
It has been found that, without impairing excellent mechanical properties, flame retardancy is imparted specifically, impact resistance and fluidity are improved, light resistance, and surface appearance after dry heat treatment are good. .

That is, according to the present invention, there are provided "(A) 100 parts by weight of a polystyrene resin, (B) the following general formula (1)
And 1 to 30 parts by weight of an aromatic phosphate represented by the formula: and (C) a silicone rubber whose weight loss at 800 ° C is 50% or less in a heating test (heating rate: 40 ° C / min) in air. Or a flame-retardant resin composition containing 0.2 to 4 parts by weight of a silicone resin.

[0010]

Embedded image (In the formula, R ¹ to R ⁸ represent identical or different hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The 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. Y is a direct bond, O, S, S
O ₂ , C (CH ₃ ) ₂ , CH ₂ , and CHPh, and Ph represents a phenyl group. Further, 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. )

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition of the present invention will be specifically described below.

The polystyrene resin of the present invention includes polystyrene, styrene / acrylonitrile copolymer, rubber-modified styrene resin, polymer blend of rubber-modified styrene resin and polyphenylene oxide (modified polyphenylene oxide resin) and the like. .

Here, the rubber-modified styrenic resin refers to a graft polymer in which a rubbery polymer is dispersed in a fine particle form in a matrix made of a vinyl aromatic polymer. By adding an aromatic vinyl monomer and, if necessary, a vinyl mixture copolymerizable therewith to the monomer mixture by known bulk polymerization, bulk suspension polymerization, solution polymerization, or emulsion polymerization. can get.

Such rubber-modified styrene resins include, for example, impact-resistant polystyrene, ABS resin, AA
S resin (acrylonitrile-acryl rubber-styrene copolymer), AES resin (acrylonitrile-ethylene propylene rubber-styrene copolymer) and the like are exemplified.

As such a rubber-modified styrenic resin, one having a structure in which a (co) polymer containing a styrene monomer is grafted to a rubbery polymer, and another having a structure containing a styrene monomer (co) It includes those having a structure in which the polymer is not grafted to the rubbery polymer.

Specifically, 95 to 20 parts by weight of a monomer or monomer mixture containing 20% by weight or more of an aromatic vinyl monomer is graft-polymerized to 5 to 80 parts by weight of a rubbery polymer. The obtained (a) graft (co) polymer is obtained by polymerizing 5 to 100% by weight of a monomer or monomer mixture containing at least 20% by weight of an aromatic vinyl monomer and (b).
Those comprising from 0 to 95% by weight of a vinyl (co) polymer are preferred.

As the rubbery polymer, those having a glass transition temperature of 0 ° C. or less are suitable, and diene rubbers are preferably used. Specifically, polybutadiene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, styrene-butadiene block copolymer,
Examples include diene rubbers such as butyl acrylate-butadiene copolymer, acrylic rubbers such as polybutyl acrylate, polyisoprene, and ethylene-propylene-diene terpolymer. Among them, polybutadiene or butadiene copolymer is preferred.

The rubber particle diameter of the rubbery polymer is not particularly limited, but the weight average particle diameter of the rubber particles is 0.15 to 0.6.
μm, especially 0.2 to 0.55 μm, is preferable because of its excellent impact resistance. Among them, 0.20 to 0.25 μm and 0.5
The weight ratio to 0 to 0.65 μm is 90:10 to 60:40.
Is preferable because the impact resistance and falling weight impact of a thin molded product are remarkably excellent.

The average weight particle size of the rubber particles is "Ru
bber Age Vol. 88p. 484-490
(1960) by E.I. Schmidt, P .; H. B
sodium salt alginate method described in “Idison” (particles having a cumulative weight fraction of 50% from the cumulative weight fraction of the creamed weight ratio and the sodium alginate concentration utilizing the fact that the particle size of polybutadiene to be creamed varies depending on the concentration of sodium alginate) (Determining the diameter).

As the aromatic vinyl monomer, styrene,
Examples include α-methylstyrene, vinyltoluene, o-ethylstyrene, pt-butylstyrene, etc., with styrene being particularly preferred.

As monomers other than the aromatic vinyl monomers, vinyl cyanide monomers are used for the purpose of further improving impact resistance, and (meth) acrylic monomers are used for the purpose of improving toughness and color tone. Acid ester monomers are preferably used. Examples of the vinyl cyanide-based monomer include acrylonitrile, methacrylonitrile, ethacrylonitrile, and the like, and acrylonitrile is particularly preferable. Examples of the (meth) acrylate-based monomer include methyl and ethyl esters of acrylic acid and methacrylic acid with ethyl, propyl, n-butyl and i-butyl. Particularly, methyl methacrylate is preferred.

If necessary, other vinyl monomers,
For example, maleimide monomers such as maleimide, N-methylmaleimide, and N-phenylmaleimide can be used.

The monomer or monomer mixture used in the (a) graft (co) polymer is preferably at least 20% by weight of an aromatic vinyl monomer from the viewpoint of the impact resistance of the resin composition. It is preferably at least 50% by weight. When a vinyl cyanide monomer is mixed, the amount is preferably 60% by weight or less, and more preferably 50% by weight or less, from the viewpoint of moldability of the resin composition. When a (meth) acrylate monomer is mixed, the content is preferably 80% by weight or less, and more preferably 75% by weight or less, from the viewpoint of toughness and impact resistance. The total amount of the aromatic vinyl-based monomer, vinyl cyanide-based monomer and (meth) acrylate-based monomer in the monomer or monomer mixture is preferably 95 to 20% by weight, and Preferably 90 to
30% by weight.

(A) The ratio of the rubbery polymer to the monomer mixture in obtaining the graft (co) polymer is preferably at least 5 parts by weight of the rubbery polymer based on 100 parts by weight of the total graft copolymer. More preferably, the amount is 10 parts by weight or more, and 80 parts by weight or less, more preferably 70 parts by weight or less. The amount of the monomer or monomer mixture is preferably 95 parts by weight or less, more preferably 90 parts by weight or less, and 2 parts by weight or less.
It is preferably at least 0 parts by weight, more preferably at least 30 parts by weight. When the proportion of the rubbery polymer is less than 5 parts by weight, the impact resistance of the resin composition is reduced, and when it exceeds 80 parts by weight, the impact resistance of the resin composition and the appearance of a molded product may be impaired.

(A) The graft (co) polymer can be obtained by a known polymerization method. For example, it can be obtained by a method in which a mixture of a monomer and a chain transfer agent and a solution of a radical generator dissolved in an emulsifier are continuously supplied to a polymerization vessel in the presence of a rubbery polymer latex to carry out emulsion polymerization.

(A) The graft (co) polymer is a material containing a non-grafted copolymer in addition to a material having a structure in which a monomer or a monomer mixture is grafted on a rubbery polymer. It is. (A) The graft ratio of the graft (co) polymer is not particularly limited, but is preferably from 20 to 80% by weight, particularly preferably from 25 to 50% by weight in order to obtain a resin composition having excellent impact resistance and gloss. .

Here, the graft ratio is calculated by the following equation. Graft ratio (%) = <amount of vinyl copolymer graft-polymerized on rubbery polymer> / <rubber content of graft copolymer> × 100 The characteristics of the ungrafted (co) polymer are particularly limited. The intrinsic viscosity [η] (measured at 30 ° C.) of the methyl ethyl ketone soluble component is 0.25 to 0.6 dl /
g, especially in the range of 0.25 to 0.5 dl / g;
N-dimethylformamide solvent, 0.25 to 0.75 dl / g when measured at 30 ° C., particularly 0.35 to 0.7
Those having a dl / g range are preferably used because a resin composition having excellent impact resistance can be obtained.

(B) The vinyl (co) polymer is a copolymer essentially containing an aromatic vinyl monomer. Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, p-methylstyrene, t-butylstyrene, vinyltoluene, o-ethylstyrene, and the like, with styrene being particularly preferred. One or more of these can be used.

As a monomer other than the aromatic vinyl monomer, a vinyl cyanide monomer is preferably used for the purpose of further improving impact resistance. For the purpose of improving toughness and color tone, (meth) acrylate monomers are preferably used. Examples of the vinyl cyanide-based monomer include acrylonitrile, methacrylonitrile, ethacrylonitrile, and the like, and acrylonitrile is particularly preferable.
(Meth) acrylic ester monomers include acrylic acid and methacrylic acid methyl, ethyl, propyl, n
Examples thereof include an esterified product with -butyl and i-butyl, and methyl methacrylate is particularly preferable.

As other vinyl monomers copolymerizable therewith, maleimide monomers such as maleimide, N-methylmaleimide and N-phenylmaleimide can be used as required.

(B) From the viewpoint of the impact resistance of the resin composition, the proportion of the aromatic vinyl monomer as a constituent component of the vinyl (co) polymer is preferably at least 20% by weight based on all monomers. Preferably, it is more preferably at least 50% by weight. When a vinyl cyanide monomer is mixed, the content is preferably 60% by weight or less, more preferably 50% by weight or less, from the viewpoint of impact resistance and fluidity. When a (meth) acrylate monomer is mixed, the amount is preferably 80% by weight or less, more preferably 75% by weight or less from the viewpoint of toughness and impact resistance. When other vinyl monomers copolymerizable therewith are mixed, the content is preferably 60% by weight or less, more preferably 50% by weight or less.

Although the characteristics of the vinyl (co) polymer are not limited, the intrinsic viscosity [η] (methyl ethyl ketone solvent, 30 ° C.
Measurement) is 0.4 to 0.65 dl / g, especially 0.45 to
In the range of 0.55 dl / g, an N, N-dimethylformamide solvent, when measured at 30 ° C., 0.35 dl / g.
A resin composition in the range of from 0.85 dl / g to 0.45 dl / g, particularly from 0.45 to 0.7 dl / g, is preferred, since a resin composition having excellent impact resistance and moldability can be obtained.

The method for producing the vinyl (co) polymer is not particularly limited, and includes bulk polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization.
Conventional methods such as a suspension polymerization method and a solution-bulk polymerization method can be used.

In the present invention, a carboxyl group, a hydroxyl group, an epoxy group, an amino group,
A modified vinyl polymer containing at least one functional group selected from oxazoline groups (hereinafter abbreviated as a modified vinyl polymer) can also be used. The modified vinyl polymer has a structure obtained by polymerizing or copolymerizing one or more vinyl monomers, and has a carboxyl group, a hydroxyl group, an epoxy group,
It is a polymer containing at least one functional group selected from an amino group and an oxazoline group. The content of the compound containing these functional groups is not limited, but is preferably in the range of 0.01 to 20% by weight in the modified vinyl polymer.

The method for introducing a carboxyl group into the modified vinyl polymer is not particularly limited, but may be a carboxyl group such as acrylic acid, methacrylic acid, maleic acid, maleic acid monoethyl ester, maleic anhydride, phthalic acid and itaconic acid. Or a method of copolymerizing a vinyl monomer having an anhydrous carboxyl group with a predetermined vinyl monomer, γ, γ
Polymerization generators having a carboxyl group such as' -azobis (γ-cyanovaleic acid), α, α'-azobis (α-cyanoethyl) -p-benzoic acid and succinic acid peroxide and / or thioglycolic acid, α-mercapto Using a polymerization degree controlling agent having a carboxyl group such as propionic acid, β-mercaptopropionic acid, α-mercapto-isobutyric acid and 2,3 or 4-mercaptobenzoic acid, a predetermined vinyl monomer is (co) A method of polymerizing, and a copolymer of a (meth) acrylate monomer such as methyl methacrylate and methyl acrylate with an aromatic vinyl monomer and, if necessary, a vinyl cyanide monomer. A method of saponifying with an alkali or the like can be used.

The method for introducing a hydroxyl group is not particularly limited. For example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 3,4,5,6-pentahydroxyhexyl, 2,3,4,5,6-pentahydroxyhexyl methacrylate, 2,3,4,5-acrylic acid
Tetrahydroxypentyl, 2,3,4, methacrylic acid
5-tetrahydroxypentyl, 3-hydroxy-1-
Propene, 4-hydroxy-1-butene, cis-4-hydroxy-2-butene, trans-4-hydroxy-2
-Butene, 3-hydroxy-2-methyl-1-propene, cis-5-hydroxy-2-pentene, trans-
5-hydroxy-2-pentene, 4-dihydroxy-2
-A method of copolymerizing a vinyl monomer having a hydroxyl group such as butene with a predetermined vinyl monomer can be used.

The method for introducing an epoxy group is not particularly limited. For example, glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, glycidyl itaconate, allyl glycidyl ether, styrene-p
-A method of copolymerizing a vinyl monomer having an epoxy group such as glycidyl ether or p-glycidyl styrene with a predetermined vinyl monomer can be used.

The method for introducing an amino group is not particularly limited. For example, acrylamide, methacrylamide, N-methylacrylamide, butoxymethylacrylamide, N-propylmethacrylamide, aminoethyl acrylate, propylaminoethyl acrylate, methacryl Dimethylaminoethyl acrylate, ethylaminopropyl methacrylate, phenylaminoethyl methacrylate, cyclohexylaminoethyl methacrylate, N-vinyldiethylamine, N-acetylvinylamine, allylamine, methallylamine, N-methylallylamine, p-
A method of copolymerizing a vinyl monomer having an amino group such as aminostyrene or a derivative thereof with a predetermined vinyl monomer can be used.

The method of introducing the oxazoline group is not particularly limited. For example, vinyl having an oxazoline group such as 2-isopropenyl-oxazoline, 2-vinyl-oxazoline, 2-acryloyl-oxazoline and 2-styryl-oxazoline. For example, a method of copolymerizing a monomer with a predetermined vinyl monomer can be used.

Although the properties of the modified vinyl polymer are not limited, the intrinsic viscosity [η] (methyl ethyl ketone solvent, 30 ° C.
Measurement) is 0.2 to 0.65 dl / g, especially 0.35 to
In the range of 0.6 dl / g, an N, N-dimethylformamide solvent at a temperature of 30 ° C.
A resin composition in the range of 0.9 dl / g, particularly 0.4 to 0.75 dl / g is preferable because excellent flame retardancy, impact resistance and moldability can be obtained.

The aromatic phosphate (B) used in the present invention is represented by the following formula (1).

[0042]

Embedded image First, the structure of the flame retardant represented by the formula (1) will be described. In the formula (1), 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. Preferably, k and m are each an integer of 0 or more and 1 or less, particularly preferably k or m. Is 1.

In the formula (1), R ^{1 to} R ⁸ represent the same or different hydrogen or an alkyl group having 1 to 5 carbon atoms. Here, specific examples of the alkyl group having 1 to 5 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-isopropyl, neopentyl , Tert-
Pentyl group, 2-isopropyl, neopentyl, ter
t-pentyl group, 3-isopropyl, neopentyl, t
tert-pentyl group, neoisopropyl, neopentyl, tert-pentyl group and the like.
A methyl group and an ethyl group are preferable, and hydrogen is particularly preferable.

Ar ¹ , Ar ² , Ar ³ and Ar ⁴ represent the same or different phenyl groups or phenyl groups substituted by halogen-free organic residues. Specific examples include a phenyl group, a tolyl group, a xylyl group, a cumenyl group,
Examples include a mesityl group, a naphthyl group, an indenyl group, an anthryl group, and the like. A phenyl group, a tolyl group, a xylyl group, a cumenyl group, and a naphthyl group are preferable, and a phenyl group, a tolyl group, and a xylyl group are particularly preferable.

Y is a direct bond, O, S, SO ₂ , C
(CH ₃ ) ₂ , CH ₂ , and CHPh, and Ph represents a phenyl group.

Such aromatic phosphates include:
More specifically, "PX-200" and "PX-200" manufactured by Daihachi Chemical Co., Ltd.
-201 "," CR-733S "," CR-741 ",
“CR747”, “TCP”, “TXP”, “CDP”
And "TPP" can be used.

In the present invention, a mixture of two or more aromatic phosphates may be used.

The amount of the aromatic phosphate used is 1 to 30 parts by weight, preferably 2 to 25 parts by weight, and more preferably 3 to 30 parts by weight based on 100 parts by weight of the polystyrene resin.
-20 parts by weight.

If the amount of the aromatic phosphate used is less than 1 part by weight, the effect of improving the flame retardancy is not recognized.
Exceeding 0 parts by weight is not preferred because the mechanical properties and heat resistance of the molded article are impaired.

The silicone rubber or silicone resin (C) used in the present invention is represented by the following general formulas (4) to (7)
Wherein R is a saturated or unsaturated monovalent hydrocarbon group, a hydrogen atom, a hydroxyl group, an alkoxyl group, an aryl group, a vinyl group. Or a group selected from allyl groups).) Or a polyorganosiloxane resin-like polymer or copolymer.

[0051]

Embedded image Further, such a polyorganosiloxane resin-like polymer or copolymer may further have an epoxy group, an acryloxy group, a methacryloxy group, a vinyl group, a phenyl group, an N-β- (N-
Those containing a vinylbenzylamino) ethyl-γ-aminoalkylhydrochloride group and a hydroxyl group can be used. Among them, those containing an epoxy group, an acryloxy group and a methacryloxy group can be preferably used. Particularly, those containing a methacryloxy group have excellent dispersibility in the polystyrene resin (A),
Since it exhibits a high flame retardant effect, it can be preferably used.

In the case of silicone rubber, a powdery or powdery rubber at room temperature is preferred, and in the case of a silicone resin, a powdery or flake-like one is preferred.

The silicone rubber and / or silicone resin (C) used in the present invention is a thermogravimetric / differential thermogravimeter (TG / DT, manufactured by Seiko Instruments Inc.) in air.
A-200), in a heating test performed in a temperature range of 100 to 900 ° C. at a rate of temperature increase of 40 ° C./min, 80
It is necessary that the weight loss at 0 ° C. is 50% or less, and particularly preferably 30% or less.

The (C) silicone rubber and / or silicone resin used in the present invention is 800 ° C.
There is no particular limitation as long as the weight loss is less than 50%, but within the scope of the present invention, those further blended with a silica filler can be used. In particular, when a silica filler is blended with the silicone rubber, the dispersibility of the silicone rubber in the resin composition is improved, and the synergistic effect of the silica filler and the silicone rubber reduces the weight loss at 800 ° C. and the flame retardancy is reduced. It is preferable because the heat resistance is improved by the reinforcing effect of the silica filler. In particular, it is more effective in the case of silicone rubber powder.

As a method of mixing the silicone rubber and the silica filler, a generally known method can be applied. Further, an alkoxysilane coupling agent can be blended with the composition comprising the silicone rubber and the silica filler.

Such silane coupling agents include at least one alkoxy group having 1 to 4 carbon atoms in the molecule, and further include an epoxy group, an acryloxy group, a methacryloxy group, a vinyl group, a phenyl group, an N-β- A silane coupling agent containing (N-vinylbenzylamino) ethyl-γ-aminoalkyl hydrochloride group and hydroxyl group can be used. Among them, a silane coupling agent containing epoxy group, acryloxy group and methacryloxy group can be used. An agent can be preferably used.

In order to obtain the effect of the present invention, it is necessary to use a silicone rubber and / or a silicone resin, and
It is important that the weight loss in ° C. is not more than 50%.

In the present invention, a silicone rubber and a silicone resin can be used in combination.
The weight loss at 00 ° C. may be 50% or less.

As the silicone rubber or silicone resin (C), those produced by a generally known method can be used.

The silicone rubber and / or silicone resin is added in an amount of 0.2 to 4 parts by weight, preferably 0.3 part by weight, per 100 parts by weight of the polystyrene resin.
To 3 parts by weight, more preferably 0.4 to 2 parts by weight.

By blending a small amount of the above-mentioned silicone rubber and / or silicone resin, which is characterized by weight loss with heating, with an aromatic phosphate in a polystyrene resin within the scope of the present invention, specific flame retardancy is imparted. It is possible to do.

Further, the resin composition of the present invention not only has improved flame retardancy, but also has improved impact resistance, fluidity and heat resistance, and is excellent in light resistance, and its surface appearance is changed even after dry heat treatment. And excellent heat stability.

On the other hand, when a silicone oil, a silicone rubber or a silicone resin whose weight loss on heating at 800 ° C. exceeds 50% is used, sufficient flame retardancy cannot be imparted and light resistance deteriorates. Not preferred.

The flame-retardant resin composition of the present invention further comprises (D)
By blending a phosphorus compound having a P—H bond in a molecule represented by the following general formula (2), dripping is specifically promoted during combustion, and high flame retardancy with reduced combustion time is imparted. It becomes possible.

[0065]

Embedded image (R ⁹ and R ¹⁰ are the same or different groups selected from an alkyl group, an aryl group, an alkoxy group and an allyloxy group, and R ¹ and R ² may form a ring with each other.) Specific examples of the phosphorus compound include the following.

[0066]

Embedded image Among them, a phosphorus compound represented by the following general formula (3) can be preferably used.

[0067]

Embedded image The amount of the phosphorus compound represented by the above general formula (2) is 0.1 to 5 parts by weight, preferably 0.2 to 4 parts by weight, more preferably 0 to 100 parts by weight of the polystyrene resin. 0.5 to 3 parts by weight.

The flame-retardant resin composition of the present invention can further impart a high flame-retardant property with a reduced burning time by blending a coloring agent (E), and also has excellent light resistance. Can be granted.

Here, the colorant is not particularly limited, and one or more known colorants can be used as needed, and examples thereof include organic pigments, inorganic pigments, and dyes. Organic pigments include, for example, azo pigments; acetoacetarylides, pyrazolones, 2,3-oxynaphthoylarylamides, palpitur oxygen, thioparpitur oxygen, 2,4,6-triamino-1,3
-Pyrimidine-based, 3-cyano-4-methylpyridone-based monoazo or disazo compounds and those selected from the group consisting of metal salts of azo compounds, and other organic pigments; copper phthalocyanine, ultramarine, and the like can be used. Examples of the inorganic pigment include Prussian blue, copper chromate, copper sulfochromate, titanium black, Ketjen black, carbon black, black iron oxide, red iron oxide, white titanium and the like. These colorants include those which have been surface-treated with a silane coupling agent, a surfactant, a lubricant, silicon oxide or the like in order to improve compatibility with the resin.

The amount of the colorant used is not particularly limited, but (A) 100 parts by weight of the polystyrene resin.
Usually, it is 0.1-5 parts by weight, preferably 0.5-5 parts by weight, more preferably 1-4 parts by weight.

Further, the flame-retardant resin composition of the present invention may contain, if necessary, a flame-retardant auxiliary such as a fluororesin or a phenolic resin, glass fiber, carbon fiber, metal fiber, aramid fiber,
Asbestos, potassium titanate whiskers, wollastenite, glass flakes, glass beads, talc, mica,
Fillers such as clay, calcium carbonate, barium sulfate, titanium oxide and aluminum oxide can be blended.

Further, as long as the object of the present invention is not impaired, an antioxidant such as a hindered phenol-based, phosphorus-based or sulfur-based antioxidant, a heat stabilizer, an ultraviolet ray, etc. may be added to the flame-retardant resin composition of the present invention. Absorbents (eg, resorcinol, salicylate, benzotriazole, benzophenone, etc.), lubricants and release agents (eg, montanic acid and its salts, esters, half-esters, stearyl alcohol, stella amide and ethylene wax), anti-coloring agents (eg, One or more conventional additives such as phosphates, hypophosphites, nucleating agents, plasticizers, and antistatic agents can be added.

The flame-retardant resin composition of the present invention is produced by a generally known method. For example, (A) a polystyrene resin, (B) an aromatic phosphate, (C) a silicone rubber and / or a silicone resin and other necessary additives are supplied to an extruder or the like with or without premixing, It is prepared by sufficiently melting and kneading in a temperature range of 150 ° C to 350 ° C. In this case, for example, a single screw extruder with a screw of the "Unimelt" type, a twin screw,
A triaxial extruder and a kneader-type kneader can be used. In particular, since the aspect ratio is controlled, it is preferable to use a screw by inserting several kneading elements or not inserting them.

The flame-retardant resin composition of the present invention is excellent not only in flame retardancy but also in mechanical properties, heat resistance, light resistance and molding processability.
Press molding is possible, and it can be formed into a film, a tube, a rod or a molded product having any desired shape and size. Furthermore, by utilizing the flame retardancy, it can be used for various applications such as housings for electric / electronic parts, automobile parts, mechanical mechanism parts, OA equipment, home electric appliances and the like and parts thereof.

For example, various gears, various cases, sensors, LEP lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors,
Variable condenser case, optical pickup, oscillator, various terminal boards, transformer, plug, printed wiring board, tuner, speaker, microphone, headphone, small motor, magnetic head base, power module, housing, semiconductor, liquid crystal, FDD carriage, FDD Chassis, motor brush holder, parabolic antenna,
Electrical and electronic parts such as computer-related parts; VTR parts, TV parts, irons, hair dryers, rice cooker parts, microwave parts, audio parts, audio equipment parts such as audio, laser disks, and compact disks, and lighting parts , Refrigerator parts, air conditioner parts, typewriter parts, word processor parts, home, office electrical product parts, office computer related parts, telephone related parts, facsimile related parts,
Copier-related parts, cleaning jigs, various bearings such as oilless bearings, stern bearings, underwater bearings, etc., motor parts, machine-related parts such as lighters, typewriters, microscopes, binoculars, cameras, watches, etc. Representative optical equipment and precision machinery related parts; alternator terminal, alternator connector, IC regulator, various valves such as exhaust gas valve, various fuel related / exhaust / intake system pipes, air intake nozzle snorkel, intake manifold, fuel pump, engine Cooling water joint, 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 Heater, air conditioner thermostat base, heating hot air flow control valve, radiator motor brush holder, water pump impeller, turbine vane, wiper motor related parts, dust distributor, starter switch, starter relay, transmission wire harness, window washer Nozzle, air conditioner panel switch board, fuel-related electromagnetic valve coil, fuse connector, horn terminal, electrical component insulation board, step motor rotor, lamp socket, lamp reflector, lamp housing, brake piston, solenoid bobbin, engine oil filter, ignition Useful for device cases and the like.

[0076]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples. In the examples, the number of parts and% indicate parts by weight and% by weight, respectively, and the unit "" means inches (1 inch = 2.54 cm). Reference Example 1 (A1) Preparation of graft copolymer A method for preparing a graft copolymer is described below. The graft ratio was determined by the following method. Acetone was added to a predetermined amount (m) of the graft copolymer and refluxed for 4 hours. The solution was centrifuged at 8000 rpm (centrifugal force: 10,000 G
0 × 10 3 m / s 2)) After 30 minutes of centrifugation, insolubles were filtered. This insoluble matter was dried under reduced pressure at 70 ° C. for 5 hours, and the weight (n) was measured.

Graft ratio = [(n)-(m) × L] /
[(M) × L] × 100 Here, L means the rubber content of the graft copolymer.

60 parts of polybutadiene latex (average rubber particle diameter 0.3 μm, gel content 85%) (in terms of solid content)
And 40 parts of a monomer mixture composed of 70% of styrene and 30% of acrylonitrile were added thereto to carry out emulsion polymerization. The obtained graft copolymer was coagulated with sulfuric acid, neutralized with caustic soda, washed, filtered and dried to prepare a powdery graft copolymer <A-1>.

The resulting graft copolymer <A-1> had a graft ratio of 36%. This graft copolymer <A
-1> is a non-grafting copolymer composed of 70% of styrene structural units and 30% of acrylonitrile 18.1
%. The intrinsic viscosity of the N, N-dimethylformamide-soluble component was 0.48 dl / g. Reference Example 2 <A-2> Preparation of vinyl copolymer A monomer mixture composed of 70% styrene and 30% acrylonitrile was subjected to suspension polymerization to prepare a vinyl copolymer <A-2>. The obtained vinyl copolymer <A-2> is N,
The intrinsic viscosity of the N-dimethylformamide-soluble component is 0.73
Met. Reference Example 3 (B) Aromatic phosphate <B-1> An aromatic bisphosphate "PX-200" (manufactured by Daihachi Chemical Co., Ltd.) represented by the following formula (8) was used.

[0080]

Embedded image <B-2> Triphenyl phosphate "TPP" (manufactured by Daihachi Chemical Co., Ltd.) was used. Reference Example 4 (C) Silicone Compound The silicone rubber or silicone resin having a weight loss at 800 ° C. of 50% or less used in the examples is as follows. <C-1>"DC4-710" which is a silicone rubber powder having no reactive functional group and containing a silica filler.
5 "(manufactured by Dow Corning Toray Silicone Co., Ltd.) This silicone resin was used for simultaneous measurement of differential thermogravimetry (TG / DTA-200, manufactured by Seiko Instruments Inc.).
To a temperature range of 100 to 900 ° C in air by using
As a result of performing a heating test at a heating rate of 0 ° C./min, 800 ° C.
Was 26%. <C-2>"DC4-7081" which is a silicone rubber powder containing a methacryloxy group as a reactive functional group and blended with a silica filler (Dow Corning Toray Toray)
Silicone Co., Ltd.) was used. Weight loss at 800 ° C. was 26.9%. <C-3> containing an epoxy group as a reactive functional group,
In addition, “DC4-7051” (manufactured by Dow Corning Toray Silicone Co., Ltd.), which is a silicone rubber powder containing a silica filler, was used. Weight loss at 800 ° C is 2
It was 8.6%. <C-4>"Tospearl" 2000B (manufactured by Toshiba Silicone Co., Ltd.), which is a silicone resin powder having no reactive functional group, was used. 13. Weight loss at 800 ° C.
7%. <C-5> KMP590 (manufactured by Shin-Etsu Chemical Co., Ltd.), which is a silicone resin powder having no reactive functional group, was used. Weight loss at 800 ° C. was 12.9%.

The silicone oil and silicone rubber which are outside the scope of the present invention and used in the comparative examples are as follows. <C-6> “SH200” (manufactured by Dow Corning Toray Silicone Co., Ltd.), which is a silicone oil having no reactive functional group, was used. The silicone oil was subjected to a heating test in the same manner as described above. As a result, the weight loss at 800 ° C. was 77%. <C-7> KMP594 (manufactured by Shin-Etsu Chemical Co., Ltd.), which is a silicone rubber powder having no reactive functional group, was used. Weight loss at 800 ° C. was 55.2%. Reference Example 5 (D) Phosphorus compound having a P—H bond <D-1> The phosphorus compound “HCA” of the above formula (3) (manufactured by Sanko Chemical Co., Ltd.) was used. Reference Example 6 (E) Colorant <E-1> A gray colorant CN464 (manufactured by Nippon Pigment Corporation) containing titanium white as a main component was used. Reference Example 7 (F) Phenolic resin <F-1> PR531 which is a phenol novolak resin
95 (manufactured by Sumitomo Durez Corporation) was used. Examples 1 to 10, Comparative Examples 1 to 12 Table 1 shows (A) polystyrene resin, (B) aromatic phosphate, (C) silicone rubber, silicone resin and other necessary additives prepared in Reference Examples. The mixture was mixed at the mixing ratio described above, and a pellet-shaped polymer was produced by melt-kneading and extruding using a vented 30 mmφ twin-screw extruder (PCM-30, manufactured by Ikegai Iron Works Co., Ltd.). Next, injection molding machine (Promat 40/25, manufactured by Sumitomo Heavy Industries, Ltd.)
Each test piece was molded at an injection pressure of the lower limit pressure +1 MPa, and the physical properties were measured under the following conditions. (1) Flame retardancy (a) UL94: 1/4 "and 1/16" thickness flame retardancy test specimens (125 mm length x 13 mm width) obtained by injection molding are specified in UL94. Flame retardancy was evaluated according to the evaluation criteria. Flame retardant level is V-0
>V-1>V-2> HB. (B) Flame retardancy on square plate: 80 mm × obtained by injection molding
The center of the lower end of the square plate having a thickness of 80 mm x 2 mm is burned for 10 seconds with a flame of a burner defined in UL94, and thereafter,
It was evaluated whether the flame on the square plate extinguished within 30 seconds. Ten samples were evaluated for one sample.
The number of flames on the side of the zero square plate that extinguished within 30 seconds was shown. (2) 1/2 "Izod impact strength: ASTM D25
The impact resistance was evaluated according to 6-56A. (3) Deflection temperature under load: ASTM D648 (Load:
The heat resistance was evaluated according to 1.82 MPa). (4) Fluidity: Using a melt indexer (manufactured by Toyo Seiki Co., Ltd.), the outflow MI value (g / 10 minutes) at 220 ° C. for 10 minutes under a load of 10 kg was measured. The larger the MI value, the better the fluidity. (5) Surface appearance after dry heat treatment: The test piece of ASTM No. 1 dumbbell was subjected to dry heat treatment at 80 ° C. for 3 days in a gear oven, and the surface appearance was visually observed, and the thermal discoloration was determined by the following index.

：: No change from before the dry heat treatment. が あ る: Some parts have yellowed. ×: The whole molded article has yellowed. (6) Light fastness: Exposure using a test piece for evaluating flame retardancy Equipment (Atlas Co., Xenon Weather Meter Ci35
(Type), temperature 55 ° C., humidity 50% RH, irradiation illuminance 0.7 W / m ² (wavelength 420 nm), irradiation time 100 hours, and color difference (Δ) according to JIS K7105.
E) Measurement was performed. The smaller the value of ΔE, the better the light resistance.

The composition of each sample, flame retardancy, impact resistance,
Measurement results of heat resistance, fluidity, surface appearance after dry heat treatment, and light resistance are summarized in Tables 1 and 2.

[0084]

[Table 1]

[0085]

[Table 2] From the measurement results of Examples 1 to 10 and Comparative Examples 1 to 12, AB
When silicone rubber powders <C1> to <C3> or silicone resins <C-4> and <C-5> within the scope of the present invention are used in combination with the aromatic phosphate and the S resin, UL9 is obtained.
In the flame retardancy test of No. 4, both the thick molded product (1/8 ") and the thin molded product (1/16") have improved flame retardancy and also improved fluidity, impact resistance and heat resistance. I understand.
In addition, it is found that the resin composition has good light resistance and does not change the surface appearance even after the dry heat treatment.

In Example 10, silicone rubber powder <C-1> having a weight loss of 26% at 800 ° C. was added to 800 ° C.
Weight loss of 12.9% silicone resin powder <C-
5>. Even when a silicone rubber and a silicone resin exhibiting a weight loss within the range of the present invention are used in combination, both the thick molded product (1/8 ") and the thin molded product (1/16") in the UL94 flame retardancy test. It can be seen that the flame retardancy is improved and the fluidity, impact resistance and heat resistance are also improved. In addition, it is found that the resin composition has good light resistance and does not change the surface appearance even after the dry heat treatment.

Further, it can be seen that by further adding a phosphorus compound having a P—H bond, it is possible to impart a high degree of flame retardancy with a reduced burning time (Example 4,
5).

Further, from the comparison between Example 2 and Examples 6 to 9, the flame retardancy test was carried out on a square plate in which the flame spreads more easily than the flame retardancy evaluation of UL94 and flame retardancy is hardly obtained. Silicone rubber powder containing <C-
The samples using 1> to <C-3> have a large number of fire extinguishing flames on the square plate side, indicating that excellent flame retardancy can be obtained regardless of the shape of the test piece. Among them, it is found that the use of silicone rubber powder <C-2> containing a methacryloxy group as a reactive functional group shows the best flame retardancy (Example 6).

On the other hand, a resin composition containing an ABS resin containing only an aromatic phosphate and a phosphorus compound having a P—H bond has an effect of improving the flame retardancy in a thin molded product, but has an effect in a thick molded product. No flammability is obtained (Comparative Example 2,
9).

Further, even if silicone oil <C-6> which is out of the scope of the present invention is used together with aromatic phosphate, flame retardancy cannot be obtained (Comparative Example 5). When a phosphorus compound having a P—H bond is used here, an effect of improving flame retardancy is observed, but it is found that light resistance is significantly deteriorated (Comparative Example 10).

Further, even when a silicone rubber is used together with an aromatic phosphate, a silicone rubber <C-7> having a weight loss on heating outside the range of the present invention cannot be obtained (Comparative Example 12). .

Further, when the silicone rubber powder <C-1> is added in an amount outside the range of the present invention, flame retardancy cannot be obtained, and no improvement in fluidity, impact resistance and heat resistance can be observed. (Comparative Examples 3, 4, 6, and 7).

Further, when a phenolic resin is blended, the flame retardancy is improved, but the impact resistance and light resistance are remarkably reduced, and furthermore, the molded product turns yellow after the dry heat treatment and the thermal stability is poor ( Comparative Example 11).

[0094]

The resin composition of the present invention exhibits excellent flame retardancy, impact resistance, heat resistance, fluidity, thermal stability and light resistance without impairing the mechanical properties of the thermoplastic resin.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/5397 C08K 5/5397 C08L 51/04 C08L 51/04 55/02 55/02 // (C08L 25 / 02 83:04)

Claims (7)

[Claims] 1. A heating test in (B) 1 to 30 parts by weight of an aromatic phosphate represented by the following general formula (1) and (C) air in 100 parts by weight of a polystyrene resin. A flame-retardant resin composition comprising 0.2 to 4 parts by weight of a silicone rubber and / or a silicone resin having a weight loss at 800 ° C. of 50% or less at a heating rate of 40 ° C./min. Embedded image (In the formula, R ¹ to R ⁸ represent identical or different hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The 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. Y is a direct bond, O, S, S
O ₂ , C (CH ₃ ) ₂ , CH ₂ , and CHPh, and Ph represents a phenyl group. Further, 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. ) 2. The flame-retardant resin composition according to claim 1, wherein the silicone rubber (C) is a silicone rubber and / or a silicone resin containing a silica filler. 3. The silicone rubber and / or silicone resin (C) which contains a methacryloxy group as a reactive functional group in a molecule or at a molecular terminal, as the silicone rubber and / or the silicone resin.
The flame-retardant resin composition according to any one of the above. 4. The composition according to claim 1, further comprising (D) 0.1 to 5 parts by weight of a phosphorus compound represented by the following general formula (2) based on 100 parts by weight of the polystyrene resin (A). 3. The flame-retardant resin composition according to any one of 3. Embedded image (R ⁹ and R ¹⁰ are the same or different groups selected from an alkyl group, an aryl group, an alkoxy group and an aryloxy group, and R ¹ and R ² may form a ring with each other.) 5. The flame-retardant resin composition according to claim 4, wherein the phosphorus compound (D) has the following general formula (3). Embedded image 6. The flame-retardant resin according to claim 1, further comprising (E) 0.1 to 5 parts by weight of a coloring agent based on 100 parts by weight of the polystyrene resin (A). Composition. 7. A molded article comprising the flame-retardant resin composition according to claim 1.