JPH07109397A - Flame-retardant rubber-modified styrenic composition - Google Patents

Abstract

PURPOSE:To provide the composition comprising a rubber-modified styrenic resin, the ether derivative of a halogenated aromatic diol containing Na in an amount of >=10ppm, and antimony trioxide, useful for the housings of domestic electric appliances, etc., and excellent in flame resistance, heat resistance and impact resistance. CONSTITUTION:The flame-resistant rubber-modified styrenic composition comprises (A) a rubber-modified styrenic resin, (B) the ether derivative of a halogen-containing aromatic diol having a weight-average mol. wt. of 500-10000 and containing Na in an amount of >=10ppm and having a weight ratio of 500-10000, and (C) antimony trioxide. The component B is represented by the formula (R is H, CH2-CH-CH3, etc.; X is Br, Cl; i, j, k, l are independently 1-4; n is 0-30), and compounded in an amount of 10-25 pts.wt. per 100 pts.wt. of the component A. The component C is compounded in an amount of 1-10 pts.wt., preferably 3-7 pts.wt., per 100 pts.wt. of the component A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant rubber-modified styrene resin composition having excellent flame resistance, heat resistance and impact resistance.

[0002]

2. Description of the Related Art Styrenic resins are used in many fields because of their excellent moldability, mechanical properties and electrical properties. However, since it is easily flammable, it is necessary to make the resin flame-retardant when it is used for OA equipment, housings of home electric appliances and parts related to electricity and electronics. This flame retardancy is regulated by UL standards and the like, and various flame retardant means have been studied in recent years. Among them, in the housing field of home appliances, the above flame retardancy regulation and heat resistance,
Impact resistance and fluidity are required, and a well-balanced styrene-based resin satisfying all the required performances is required.

Ether derivatives of halogen-containing aromatic diols are used in many fields because of their excellent flame retardancy-providing ability. It is known that the ether derivative of a halogen-containing aromatic diol is a flame retardant effective for various polymer materials.
-27843 gazette etc. are shown.

Further, the combined use of a brominated bisphenol A type epoxy resin and antimony trioxide is disclosed in JP-A-63-72749. However, as a drawback of this flame retardant, there is a problem that the impact resistance and the heat resistance are remarkably lowered when the flame retardant is added in an amount that gives satisfactory flame retardancy.

[0005]

SUMMARY OF THE INVENTION The present invention provides a styrene-based flame retardant resin composition having excellent flame retardancy, heat resistance and impact resistance.

[0006]

That is, the present invention is as follows.
(A) rubber-modified styrenic resin, (B) sodium
Weight average molecular weight of 5 to 10 containing 0 ppm or more
000 Ether derivative of halogen-containing aromatic diol,
(C) A flame-retardant rubber-modified styrene resin composition comprising antimony trioxide.

The present invention will be described in detail below. The rubber-modified styrenic resin (A) used in the present invention is a polymer in which a rubber-like polymer is dispersed in particles in a matrix made of a styrene-based polymer. Monomer (and solution containing inert solvent)
It can be obtained by dissolving in, and stirring or performing bulk polymerization, bulk suspension polymerization, or solution polymerization to precipitate a rubber-like polymer and granulate it, but the polymerization method is not limited.

Examples of the styrene-based monomer include styrene, o-methylstyrene, p-methylstyrene,
Nuclear alkyl-substituted styrenes such as m-methyl styrene, 2,4-dimethyl styrene, ethyl styrene and p-tertiary butyl styrene, and α-alkyl substituted styrenes such as α-methyl styrene and α-methyl-p-methyl styrene. A typical example is styrene, which can be mentioned. These may be used in combination of two or more thereof.

The styrene-based polymer may be a copolymer of not only a styrene-based monomer but also another monomer, for example, an unsaturated nitrile monomer such as acrylonitrile or methacrylonitrile. The copolymer of is preferably used. Also, as the rubber-like polymer. Examples thereof include polybutadiene, styrene / butadiene copolymer, polyisoprene, butadiene / isoprene copolymer, natural rubber, and ethylene / propylene copolymer, but polybutadiene and styrene / butadiene copolymer are generally preferred. .

The ether derivative of the halogen-containing aromatic diol used in the present invention is generally represented by Chemical Formula 1.

[0011]

[Chemical 1]

The ether derivative of the halogen-containing aromatic diol may be a mixture of ether derivatives of the halogen-containing aromatic diol having different n. Specific examples thereof include reaction products of halogen-containing bisphenol A and halogen-containing bisphenol A epoxy resin, those obtained by reacting halogen-containing bisphenol A with epichlorohydrin according to a conventional method, halogen-containing bisphenol A and halogen-containing bisphenol. A
By changing the reaction ratio of the epoxy resin to make the terminal an OH group, an epoxy group, or
It is also possible to use one as an OH group and the other as an epoxy group, and the reaction products thus obtained all give a suitable flame retardant resin composition. Further, an ether derivative obtained by reacting the terminal epoxy group with tribromophenol, pentabromophenol or trichlorophenol is also a flame retardant suitable for the purpose of the present invention. Specific examples of the halogen-containing bisphenol A include tetrabromobisphenol A, dichlorobisphenol A, tetrachlorobisphenol A and dibromobisphenol A. In addition, halogen-containing bisphenol A
Specific examples of the epoxy resin include tetrabromobisphenol A diglycidyl ether, tetrachlorobisphenol A diglycidyl ether, dichlorobisphenol A diglycidyl ether, and dibromobisphenol A diglycidyl ether.

Particularly preferred are a reaction product of tetrabromobisphenol A and a diglycidyl ether of tetrabromobisphenol A, and an ether derivative obtained by reacting tetrabromobisphenol A with epichlorohydrin. The ether derivative of the halogen-containing aromatic diol represented by Chemical Formula 1 in the present invention is 10 p
It is necessary to contain sodium of pm or more. If the sodium content is lower than 10 ppm, the flame retardancy that can be imparted by the ether derivative of the halogen-containing aromatic diol decreases, so if the addition amount that can impart the required flame retardancy is added, the heat resistance and impact resistance are reduced. Lower. Further, if it exceeds 1000 ppm, the thermal stability of the resin may be deteriorated, and it is preferably in the range of 10 to 100 ppm.

The sodium content of the ether derivative of the halogen-containing aromatic diol is measured by ion chromatography or atomic absorption spectrophotometry. A method of incorporating sodium into an ether derivative of a halogen-containing aromatic diol is generally a method using a catalyst system at the time of synthesis,
The method is not limited.

Further, the ether derivative of a halogen-containing aromatic diol containing sodium in an amount within the above range often contains the same amount or more of inorganic chlorine as sodium. The term "inorganic chlorine" used herein means that a halogen-containing aromatic diol ether derivative is dissolved in toluene, and chlorine ions in the halogen-containing aromatic diol ether derivative are non-aqueous by potentiometric titration using a fixed concentration of silver nitrate. Ask.

The molecular weight of the ether derivative of the halogen-containing aromatic diol represented by Chemical Formula 1 in the present invention is 500 to 10,000 in terms of weight average molecular weight. However, the ether derivative of these halogen-containing aromatic diols may be a mixture of ether derivatives of halogen-containing aromatic diols having different n. Weight average molecular weight is 500
If it is lower, the heat resistance of the molded product and the thermal stability at the time of molding will be poor, and sufficient flame retardance cannot be imparted. On the other hand, when the weight average molecular weight is higher than 10,000, the compatibility with the resin is lowered and the impact resistance is remarkably lowered.

The ether-derived compounding amount of the halogen-containing aromatic diol represented by Chemical Formula 1 in the present invention is based on 100 parts by weight of the rubber-modified styrene resin (A) and the Underwriters Laboratory in the United States.・ Incorporation (Underwriters Lo
laboratories Inc. , U. S. 94V-0 described in "UL94 Safety Standard: Combustion test of plastic materials for parts of equipment" (4th edition) published by A).
The addition amount for imparting flame retardancy corresponding to (hereinafter abbreviated as "V-0") is preferably 10 to 25 parts by weight.
If it exceeds 25 parts by weight, the impact resistance of the obtained resin composition will decrease, and if it is less than 10 parts by weight, the flame retardancy will decrease.

The antimony trioxide, which is the component (C) of the resin composition of the present invention, is a substance that acts as a flame retardant auxiliary agent, and a commercially available product may be usually used, for example, Daiichi Kogyo Seiyaku Co., Ltd. Product name: Piroguard AN600 or the like is used. The compounding amount of this antimony trioxide is 1 to 1 with respect to 100 parts by weight of the rubber-modified styrene resin (A).
It is 0 part, preferably 3 to 7 parts by weight. If it is less than 1 part by weight, flame retardancy cannot be imparted to the obtained composition, and if it exceeds 10 parts by weight, impact resistance is significantly lowered, which is not preferable.

The method for producing the flame-retardant resin composition of the present invention comprises blending each of these components in a predetermined amount. The compounding method is not particularly limited, and there are methods such as a Henschel mixer, a tumbler mixer, a super mixer, a Banbury mixer, a kneader, a roll, a single screw extruder, and a twin screw extruder. If necessary, other additives such as a plasticizer, a lubricant, a stabilizer, an ultraviolet absorber, a filler, a coloring agent, a reinforcing agent and the like can be added to the composition of the present invention.

[0020]

EXAMPLES The evaluation methods used in Examples and Comparative Examples will be described. (1) Izod impact strength was measured according to ASTM D256 at 23 ° C. using notched test pieces. (2) Vicat softening point was measured by ASTM D1525.

(3) The melt flow rate is ISO R
1133 was measured using a granular sample. (4) Combustibility is based on Underwriters Laboratory Inc. (Underwriters)
Laboratories Inc. , U. S. A)
Based on the standard published in "UL94 Safety Standard: Combustion Test of Plastic Materials for Equipment Parts (4th Edition)", the flammability rank is 94V-2, 94V-1, 94.
It was classified into V-0 (hereinafter abbreviated as "V-2", "V-1", and "V-0").

(5) The content of the sodium ether derivative of a halogen-containing aromatic diol was measured by the atomic absorption spectrophotometry. Specifically, 1000 ppm for atomic absorption
Atomic absorption spectrophotometer (Shimadzu A
Create a calibration curve in A670). 2-5 g of an ether derivative of a halogen-containing aromatic diol is weighed and ashed at 550 ° C. in an electric furnace. After cooling to room temperature, 10 ml of a constant concentration of hydrochloric acid is added to dissolve the solid matter, and the concentration is measured with an atomic absorption spectrophotometer using a calibration curve.

Further, Table 1 shows the ether derivatives of the halogen-containing aromatic diols used in Examples and Comparative Examples.

[0024]

[Table 1]

[0025]

Example 1 100 parts of polybutadiene-modified polystyrene was used.
A twin-screw extruder is prepared by mixing an ether derivative of a halogen-containing aromatic diol containing 30 ppm of sodium (tribromophenol group-terminated) and antimony trioxide in a predetermined amount with respect to parts by weight in a ratio shown in the table. After melt-kneading at (cylinder setting temperature 200 ° C.), injection molding was performed to prepare a test piece.

Using this test piece, Izod impact strength, Vicat softening point, melt flow rate and flammability were measured. The results are shown in Table 2.

[0027]

[Table 2]

[0028]

Example 2 The Izod impact strength was the same as in Example 1 except that an ether derivative of a halogen-containing aromatic diol having a sodium content of 40 ppm was used.
The Vicat softening point, melt flow rate and flammability were measured and the results are shown in Table 2.

[0029]

[Comparative Examples 1 and 2] Izod impact strength, Vicat softening point, melt flow rate, flammability were the same as in Example 1 except that a halogen-containing aromatic diol ether derivative having a sodium content of 1 ppm or less was used. Was measured and the results are shown in Table 2.

[0030]

The resin composition of the present invention has excellent flame retardancy, heat resistance, impact resistance and economy. Therefore, it is expected to be effectively used in a field where flame retardancy is particularly required, specifically, home electric appliances, office machines, housings of information equipment, and the like.

Claims (1)

[Claims] 1. A rubber-modified styrene resin, (B)
Flame-retardant rubber-modified styrene-based resin composition comprising (C) antimony trioxide, an ether derivative of a halogen-containing aromatic diol having a weight average molecular weight of 500 to 10,000 containing sodium in an amount of 10 ppm or more.