JPH04239043A - Flame-retardant styrenic resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. excellent in flame retardance, light resistance, heat resistance, and impact strength by compounding a rubber-modified vinylarom. resin, specific compds., and Sb2O3 each in a specified amt. CONSTITUTION:The title compsn. comprises 100 pts.wt. rubber-modified vinylarom. resin (A) (e.g. a polybutadiene-modified PS), 10-25 pts.wt. compd. (B) of formula I [wherein R is H or a group of formula II or III (wherein each R' is independently a lower alky group or a phenyl group optionally substd. by Br or Cl); X is Br or Cl; l is 1-4; and n is 0-30] having a wt.-average mol.wt. of 500-200O, 10-2 pts.wt. brominated organophosphorus compd. (C) of formula IV (wherein R is 1-15C hydrocarbon group; and n is 1-3), and 1-10 pts.wt. Sb2O3, provided that the sum of compds. B and C is 15-26 pts.wt.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a styrene resin composition, and more particularly, to a styrenic resin composition that has excellent flame retardancy, as well as light resistance, heat resistance, and impact resistance.

0002

BACKGROUND OF THE INVENTION In recent years, polymeric materials have been used in a wide variety of applications, taking advantage of their excellent moldability, mechanical properties, and electrical properties. However, since polymeric materials are generally flammable, they are subject to many restrictions on use as various regulations regarding flame retardancy are strengthened and mandated by UL standards and the like. In particular, these polymer materials are often used for office automation equipment, housings for home appliances, electrical and electronic parts, etc., but for this purpose, it is necessary to make the resin flame retardant, and various flame retardant materials are used. Measures are being considered to make this possible.

On the other hand, in the field of OA equipment, which has been growing rapidly in recent years, in addition to the above flame retardant regulations and the heat resistance and impact resistance generally required of styrene-based flame retardant resins, a high degree of light resistance is required. In particular, there is a need for a well-balanced styrenic flame retardant resin that satisfies all of these required performances.

0004

[Problems to be Solved by the Invention] In general, flame retardants such as halogen-containing epoxy polymers, bis(tribromophenoxy)ethane, and tetrabromobisphenol A (TBA) are used to make rubber-modified vinyl aromatic resins flame retardant. Adding a fuel agent is disclosed in Japanese Patent Application Laid-Open No. 62-4737, Japanese Patent Publication No. 54-44298, and Japanese Patent Application Laid-open No. 60-192.
This is shown in Publication No. 761, etc.

[0005] However, the above TBA has the disadvantage that when blended with a thermoplastic resin, the heat resistance is greatly reduced, and when it is blended with bis(tribromophenoxy)ethane, a similar decline in heat resistance is caused. There is a drawback. In addition, in order to prevent a decrease in heat resistance, the use of a high melting point halogen flame retardant such as decabromodiphenyl oxide (DBDPO) in combination with antimony trioxide is shown in JP-A-58-187450. ing. However, such flame retardants have drawbacks such as poor dispersibility of the flame retardant and deterioration of light resistance of molded products.

Furthermore, in order to solve the above problems, the combined use of brominated bisphenol A type epoxy resin and antimony trioxide as a flame retardant was disclosed in Japanese Patent Laid-Open No. 63-7.
2749. However, a drawback of this flame retardant is that when added in an amount that provides satisfactory flame retardancy, impact resistance is reduced.

[0007]

[Means for Solving the Problems] Therefore, the present inventors have solved the problems of the prior art described above, and have achieved not only flame retardancy but also heat resistance and
We conducted extensive research to develop a styrene resin composition with excellent impact resistance and light resistance. As a result, a specific halogen-based flame retardant, a halogenated phosphate flame retardant whose flame retardant mechanism differs from that of the halogen-based flame retardant, and a flame retardant auxiliary agent are combined and blended in a certain ratio into a rubber-modified vinyl aromatic resin. We have found that this purpose can be achieved. The present invention was completed based on this knowledge.

That is, the present invention provides that (A) 100 parts by weight of rubber-modified vinyl aromatic resin, (B) the general formula

[
0009

[Chemical formula 3]

(C) General formula

[C4]

[In the formula, R is a C1 to C15 hydrocarbon;
(B) by blending 10 to 2 parts by weight of tris (tribromoneopentyl) phosphate, etc., represented by [n is 1 to 3], and (D) 1 to 10 parts by weight of antimony trioxide.
, (C) and (D) in a total amount of 10 to 25 parts by weight.
The present invention provides a flame-retardant styrenic resin composition and a molded article thereof, which are characterized in that the amount is in parts by weight.

The present invention will be explained in detail below. The rubber-modified vinyl aromatic resin (A) used in the present invention refers to a polymer in which a rubber-like polymer is dispersed in the form of particles in a matrix made of a vinyl aromatic polymer, and is generally a rubber-like polymer. is dissolved in a vinyl aromatic monomer (and a liquid containing an inert solvent), and stirred or subjected to bulk polymerization, bulk suspension polymerization, or solution polymerization to precipitate a rubbery polymer and turn it into particles. However, it is not limited to the polymerization method.

In addition to styrene, examples of the vinyl aromatic monomers include o-methylstyrene, p-methylstyrene, m-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, p-tert-butylstyrene, etc. Nuclear alkyl-substituted styrenes such as styrene, α-methylstyrene, α-methyl-p-methylstyrene, etc. can be mentioned, and the representative one is styrene. Two or more of these may be used in combination.

[0014] Also, as the rubbery polymer. Examples include polybutadiene, styrene-butadiene copolymer, polyisoprene, butadiene-isoprene copolymer, natural rubber, and ethylene-propylene copolymer.
Generally, polybutadiene and styrene-butadiene copolymers are preferred. The weight average molecular weight of the matrix portion of the rubber-modified vinyl aromatic resin constituting the resin composition of the present invention is usually adjusted to a range of 15 x 104 or more from the viewpoint of strength. Declines rapidly.

There are no particular restrictions on the rubbery polymer content in the rubber-modified vinyl aromatic resin, but it is generally 4 to 4.
15% by weight, more preferably 6-12% by weight. Further, the average particle size of the rubber particles in the rubber-modified vinyl aromatic resin is controlled within the range of 0.5 to 6.0 microns. Further, the gel content (toluene-insoluble content) in the rubber-modified vinyl aromatic resin is adjusted to 15 to 40% by weight using a conventional method, and more preferably 20 to 35% by weight. Specific examples of the flame retardant (B) represented by the general formula (I) used in the present invention include a reaction product of halogen-containing bisphenol A and a halogen-containing bisphenol A epoxy resin, and a reaction product of halogen-containing bisphenol A and epichlorohydrin. By changing the reaction ratio of halogen-containing bisphenol A and halogen-containing bisphenol A epoxy resin,
It is also possible to have an OH group at the end, an epoxy group, or an OH group at one end and an epoxy group at the other, and the reaction product obtained in this way is a suitable flame retardant resin. Give the composition. Furthermore, ether derivatives obtained by reacting the terminal epoxy group with tribromophenol, pentabromophenol or trichlorophenol are also flame retardants suitable for the purpose of the present invention. Specific examples of halogen-containing bisphenol A include tetrabromobisphenol A, dichlorobisphenol A, tetrachlorobisphenol A, dibromobisphenol A, and the like. In addition, halogen-containing bisphenol A
Specific examples of the epoxy resins include tetrabromobisphenol A diglycidyl ether, tetrachlorobisphenol A diglycidyl ether, dichlorobisphenol A diglycidyl ether, dibromobisphenol A diglycidyl ether, and the like.

Particularly preferred are reaction products of tetrabromobisphenol A and diglycidyl ether of tetrabromobisphenol A, and ether derivatives obtained by reacting tetrabromobisphenol A with epichlorohydrin. The flame retardant (B) represented by the general formula (I) in the present invention has a weight average molecular weight of 500 to 20,000. If the weight average molecular weight is lower than 500, the heat resistance of the molded product and the thermal stability during molding will be poor, and sufficient flame retardance cannot be imparted. Moreover, when the weight average molecular weight is higher than 20,000, the compatibility with the resin decreases, and the impact resistance decreases significantly.

Furthermore, the flame retardant represented by the general formula (I) (
For B), commercially available products can be used, for example, the product names of Hitachi Chemical Co., Ltd.; BR343, BR
340 and product name manufactured by Dainippon Ink and Chemicals Co., Ltd.; E
It is also possible to use C-20 and EC-36. Flame retardant (B) represented by the above general formula (I) in the present invention
The blending amount is 10 to 25 parts by weight per 100 parts by weight of the styrene resin (A). If it exceeds 25 parts by weight, the impact resistance of the resulting resin composition will decrease, and if it is less than 10 parts by weight, the flame retardance will decrease.

[0018] Furthermore, in the resin composition of the present invention, (C)
It is necessary to blend the bromine-containing organic phosphorus compound (C) represented by the above general formula (II) as a component. Examples of the bromine-containing organic phosphorus compounds include tris(tribromoneopentyl) phosphate, bis(tribromoneopentyl) dichloropropyl phosphate, and bis(tribromoneopentyl) dichloropropyl phosphate.
tribromoneopentyl) chloropropyl phosphate, bis(tribromoneopentyl) chloroethyl phosphate, bis(tribromoneopentyl) methyl phosphate, bis(tribromoneopentyl) ethyl phosphate, bis(tribromoneopentyl) phenyl phosphate, Bis(tribromoneopentyl) cresyl phosphate, bis(tribromoneopentyl) tribromophenyl phosphate, bis(dichloropropyl) tribromoneopentyl phosphate, bis(chloropropyl) tribromoneopentyl phosphate, bis(chloroethyl)tri These include bromoneopentyl phosphate, dimethyltribromoneopentyl phosphate, diethyltribromoneopentyl phosphate, diphenyltribromoneopentyl phosphate, dicresyl tribromoneopentyl phosphate, and bis(tribromophenyl)tribromoneopentyl phosphate.

[0019] The bromine-containing organic phosphorus compound (C) represented by the general formula (II) can be a commercially available product; It is also possible to use In the present invention, the blending amount of the bromine-containing organic phosphorus compound (C) represented by the general formula (II) is as follows: 1 of the styrenic resin (A)
00 parts by weight to 10 to 2 parts by weight. If it exceeds 10 parts by weight, the US Underwriters Laboratory
When the test is carried out according to UL-94, Inc.'s Flammability Test Standard for Plastic Materials, dripping occurs from the flammability test piece. Moreover, if it is less than 2 parts by weight, the effect of using the flame retardant in combination is lost, and the self-extinguishing performance in the above test decreases.

Further, in the present invention, the total amount of the flame retardant (B) represented by the general formula (I) and the bromine-containing organic phosphorus compound (C) represented by the general formula (II) is 15 parts by weight. It is necessary to adjust the amount so that the amount exceeds 26 parts by weight or less. If the total amount is less than 15 parts by weight, sufficient flame retardancy cannot be obtained, and if it exceeds 26 parts by weight, the mechanical properties such as impact resistance will be significantly reduced.

Furthermore, antimony trioxide, which is the component (D) of the resin composition of the present invention, acts as a flame retardant auxiliary agent, and usually a commercially available product may be used. Pyroguard AN600, a product made by Manufacturer, Inc., is used. The blending amount of this antimony trioxide is 1 to 10 parts per 100 parts by weight of the styrene resin (A),
Preferably it is 3 to 7 parts by weight. If it is less than 1 part by weight, flame retardancy cannot be imparted to the resulting composition, and if it exceeds 10 parts by weight, the impact resistance will be significantly reduced, which is not preferable.

The method for producing the flame retardant resin composition of the present invention involves blending each of these components in predetermined amounts. There are no particular restrictions on the blending method, and methods include Henschel mixer, tumbler mixer, super mixer, Banbury mixer, kneader, roll, single screw extruder, twin screw extruder, and the like. Other additives such as plasticizers, lubricants, stabilizers, ultraviolet absorbers, fillers, colorants, reinforcing agents, etc. can be added to the composition of the present invention, as necessary, within a range that does not impair the purpose of the present invention. .

[0023]

[Examples] The present invention will be explained below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples in any way. In the following Examples and Comparative Examples, various properties of various flame-retardant rubber-modified vinyl aromatic resins were measured and evaluated by the following methods. (1) Izod impact strength: Measured according to ASTM D256 at 23°C using a notched test piece. (2) Flexural modulus: Measured according to ASTM D648. (3) Heat deformation temperature: Measured according to ASTM D648. (4) Light resistance: Visually judge the degree of discoloration of the test piece after 300 hours of irradiation with a xenon weather meter (5) Flammability: Underwriters Laboratory, Inc. (Underwrite)
rs Laboratories Inc. , U. S.
7-1 of “UL94 Safety Standard: Combustion Test of Plastic Materials for Equipment Parts” (3rd edition) published by A)
94V-2, 94V-1, 94V-0 (
Classification into categories (hereinafter abbreviated as "V-2", "V-1", and "V-0") was based on the following criteria.

(a) Materials certified as 94V-0 must meet the following conditions. A. All samples must not emit flame and burn for more than 10 seconds after each exposure. B. Each set of 5 samples shall be exposed to the flame 10 times in total, and the total time for emitting and burning the flame shall not exceed 50 seconds. C. All specimens shall not have flammable or flameless combustion reaching the support clamps.

D. All samples should not allow flaming drops to ignite dry surgical cotton 12 inches (305 mm) below the sample. E. All samples shall not continue to burn without flame for more than 30 seconds after the second flame is removed. (b) Materials certified as 94V-1 must meet the following conditions.

A. All samples were tested after each flame application.
Do not burn with flame for more than 30 seconds. B. Each set of 5 samples shall be exposed to the flame 10 times in total, and the total time for emitting and burning the flame shall not exceed 250 seconds. C. All specimens shall not have flammable or flameless combustion reaching the support clamps.

D. All samples should not allow flaming drops to ignite dry surgical cotton 12 inches (305 mm) below the sample. E. All samples shall not continue to burn flameless for more than 60 seconds after the second flame is removed. (c) Materials certified as 94V-2 must meet the following conditions.

A. All samples were tested after each flame application.
Do not burn with flame for more than 30 seconds. B. Each set of 5 samples shall be exposed to the flame 10 times in total, and the total time for emitting and burning the flame shall not exceed 250 seconds. C. All specimens shall not have flammable or flameless combustion reaching the support clamps.

D. All samples are allowed to ignite dry surgical cotton 12 inches (305 mm) below the sample with a flaming drop. E. All samples shall not continue to burn flameless for more than 60 seconds after the second flame is removed. Examples 1 to 5 and Comparative Examples 1 to 10 BR340 manufactured by Hitachi Chemical Co., Ltd., bromine-containing brominated biphenol A epoxy resin (having a tribromophenol group at the end) was added to 100 parts by weight of polybutadiene-modified polystyrene. As a phosphorus compound, CR900 antimony trioxide manufactured by Dai-Hachi Kagaku Kogyo Co., Ltd. was mixed in a predetermined amount at the ratio shown in the table, and melt-kneaded using a twin-screw extruder (
After setting the cylinder temperature to 220℃, injection molding is carried out.
A test piece was prepared.

Using this test piece, Izod impact strength, flexural modulus, heating deformation temperature, light resistance, and flammability were measured. The results are shown in Tables 1 to 3. Examples 6 to 8 A brominated biphenol A epoxy resin (having a tribromophenol group at the end) manufactured by Asahi Kasei Corporation
A test piece was prepared in the same manner as in the above example except that ER765 was used, and its physical properties were measured. The results are shown in Table 4.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3]

[0034]

[Table 4]

[0035]

[Effects of the Invention] As mentioned above, the resin composition of the present invention is a combination of styrene resin, two specific flame retardants, and antimony trioxide in a specific ratio. In addition to having excellent flame retardancy, it also has excellent heat resistance, impact resistance, and light resistance.

Therefore, the resin composition of the present invention is expected to be particularly useful in fields where flame retardancy is required, specifically in the housings of business machines, information equipment, and the like.

Claims (1)

[Claims] [Claim 1] (A) Rubber-modified vinyl aromatic resin 100
Based on parts by weight, (B) General formula [Formula 1] (C) General formula [Formula 2] [wherein R is a C1 to C15 hydrocarbon; n is 1 to 3]
It consists of 10 to 2 parts by weight of a bromine-containing organic phosphorus compound represented by (D) and 1 to 10 parts by weight of antimony trioxide, and the total amount of (B) and (C) is 15 to 2 parts by weight.
6 parts by weight of a flame-retardant styrenic resin composition.