JPH11181199A - Flame-retardant polyphenylene ether resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin compsn. which is effectively prevented from melt- dripping on burning by compounding a compsn. comprising a polyphenylene ether resin and a polystyrene resin with an organophsphorus compd. and microcapsuled ammonium polyphosphate particles. SOLUTION: This compsn. comprises 100 pts.wt. polyphenylane ether resin compd. as ingredient A comprising 10-90 pts.wt. polyphenylene ether resin and 90-10 pts.wt. polystyrene resin, 1-100 pts.wt. polystyrene resin with an organophosphorus compd. as ingredient B, and 0.5-50 pts.wt. microcapsulated ammonium polyphosphate particles as ingredient C. A pref. polyphenylene ether resin is e.g. poly(2,6-dimethyl-1,4-phenylene) ether. The polystyrene resin includes a polymer of an arom. vinyl compd. (e.g. styrene) or the like. An example of ingredient B is tricresyl phosphate. Ingredient C is microcapsules each microcapsule of which comprises a single ammonium polyphosphate particle enclosed in a synthetic resin (e.g. polycarbodiimide) microcapsule, and ingredient C may be a single kind of or a combination of two or more kinds of microcapsules.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixture of a polyphenylene ether resin, an organic phosphorus compound and ammonium polyphosphate microencapsulated with a synthetic resin. The present invention relates to a flame-retardant polyphenylene ether-based resin composition free from halogen and having good mechanical properties.

[0002]

2. Description of the Related Art Polyphenylene ether resins have properties such as excellent mechanical properties, electrical properties, acid resistance, alkali resistance, and heat resistance, as well as low water absorption and good dimensional stability. Although it is widely used as a material for housings and chassis of OA equipment such as computers and word processors, these materials often require a high degree of flame retardancy.

Although polyphenylene ether resins have excellent flame retardancy, they are generally used as alloys with styrene resins because of poor processability, and the flame retardancy is impaired. . Flame retardation by adding a flame retardant is indispensable for industrial use, and flame retardation in which an organic phosphate compound is blended as a flame retardant is conventionally known.

[0004] However, in recent years, fire safety requirements have been increasingly noticed, and the regulations of the UL (Underwriters Laboratory) vertical combustion test for home electric appliances, OA equipment, and the like have become stricter with the years. In addition, products and parts are becoming thinner in order to reduce weight and improve economical efficiency. As a result, the fire drops when burning, damaging other products and parts. In order to prevent this, a material without dripping of fire is desired. For example, in the field of OA equipment such as printers, personal computers, fax machines, copiers, etc., almost all of the housing and chassis materials are required to be flame-retardant materials that do not melt and drip. There is a demand for flame-retardant materials that do not melt and drip during combustion even for high-pressure parts and materials around power supplies.

As a technique for preventing dripping of molten metal during combustion,
Although a method of increasing the amount of the flame retardant is known, it is not economical to use a large amount of the originally expensive flame retardant, and it is not preferable because it promotes generation of gas and deterioration of mechanical properties.
As other techniques for preventing dripping, a resin composition composed of polyphenylene ether, a flame retardant, and polytetrafluoroethylene (US Pat. No. 4,355,126) and a resin composition composed of polystyrene, silicone, and a metal salt of a carboxylic acid group IIa group (Japanese Patent Publication No. 63-10184) Gazette) is disclosed. However, the above-mentioned resin composition has a long burning time and does not have sufficient dripping prevention properties, and remains a practical problem.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a flame-retardant polyphenylene ether-based resin composition which effectively prevents the molten dripping during combustion.

[0007]

In view of such a situation,
The present inventors have solved the problems of the prior art described above, and as a result of diligent studies to develop a flame-retardant polyphenylene ether-based resin composition having excellent anti-dripping properties during combustion, as a result, polyphenylene ether-based resin and organic phosphorus-based resin It has been found that by combining the compound with ammonium polyphosphate microencapsulated with a synthetic resin, the melt dripping during combustion is reduced and the object is achieved, and the present invention has been completed.

That is, the present invention relates to (A) 10 to 90 parts by weight of polyphenylene ether resin and 90 parts of polystyrene resin.
100 parts by weight of a composition of 10 to 10 parts by weight; (B) 1 to 100 parts by weight of an organic phosphorus compound; A flame-retardant polyphenylene ether-based resin composition comprising 50 parts by weight.

Hereinafter, the present invention will be described in detail. The polyphenylene ether resin used in the present invention is a homopolymer or a copolymer having a repeating unit represented by the following formula (1) and / or (2).

[0010]

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[0011]

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(Where R1, R2, R3, R4, R
5, R6 independently represent an alkyl group having 1 to 4 carbon atoms, an aryl group, halogen, or hydrogen. However, R5 and R6 are not simultaneously hydrogen. A typical example of the homopolymer of the polyphenylene ether resin is poly (2,6-dimethyl-1,4-phenylene).
Ether, poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4
-Phenylene) ether, poly (2-ethyl-6-n-)
Propyl-1,4-phenylene) ether, poly (2-
Methyl-6-n-butyl-1,4-phenylene) ether, poly (2-ethyl-6-isopropyl-1,4-phenylene) ether, poly (2-methyl-6-hydroxyethyl-1,4-phenylene) ) Ether, poly (2-
Methyl-6-chloroethyl-1,4-phenylene) ether and the like. Among these, poly (2,6-dimethyl-1,4-phenylene) ether is particularly preferred.

The copolymer of polyphenylene ether resin is a copolymer having a phenylene ether structure as a main unit. Examples thereof include copolymers of 2,6-dimethylphenol and 2,3,6-trimethylphenol,
Copolymer of 2,6-dimethylphenol and o-cresol or 2,6-dimethylphenol and 2,3,6
-Copolymers with trimethylphenol and o-cresol.

In the polyphenylene ether resin used in the present invention, various other phenylene ether units which have been proposed to be allowed to exist in the polyphenylene ether resin so far as they do not contradict the gist of the present invention have a partial structure. It may be included as. Japanese Patent Application Laid-Open (JP-A) No. 1-29
7-428 and JP-A-63-301222, 2- (dialkylaminomethyl) -6
-Methylphenylene ether unit, and 2- (N
-Alkyl-N-phenylaminomethyl) -6-methylphenylene ether unit. Further, the polyphenylene ether resin may include a resin in which diphenoquinone or the like is bonded in a small amount in the main chain. further,
Polyphenylene ether resin modified with a compound having a carbon-carbon double bond, for example, JP-A-2-2768
23, JP-A-63-108059, JP-A-59-59724, and the like.

The production method of the polyphenylene ether resin used in the present invention is not particularly limited. For example, according to the method described in Japanese Patent Publication No. 5-13966, a polyphenylene ether resin is prepared in the presence of a copper amine catalyst. , 6-xylenol by oxidative coupling polymerization. Further, the molecular weight and the molecular weight distribution are not particularly limited.

The polystyrene resin used in the present invention is:
Vinyl aromatic polymer, rubber-modified vinyl aromatic polymer, block copolymer composed of vinyl aromatic polymer block and conjugated diene polymer block, and part or all of conjugated diene polymer block were hydrogenated It refers to a block copolymer composed of a vinyl aromatic polymer block and a conjugated diene polymer block.

Examples of the vinyl aromatic polymer include styrene, o-methylstyrene, p-methylstyrene,
nuclear alkyl-substituted styrenes such as m-methylstyrene, 2,4-dimethylstyrene, ethylstyrene and p-tert-butylstyrene; α-alkyl-substituted styrenes such as α-methylstyrene and α-methyl-p-methylstyrene; Polymers, copolymers of one or more of these with at least one of other vinyl compounds, and copolymers of two or more of these. Examples of the compound copolymerizable with the vinyl aromatic compound include methyl methacrylate, methacrylic esters such as ethyl methacrylate, acrylonitrile, unsaturated nitrile compounds such as methacrylonitrile, and acid anhydrides such as maleic anhydride. .
Among these polymers, particularly preferred polymers are polystyrene and styrene-acrylonitrile copolymer (hereinafter referred to as A
(Abbreviated as S resin)).

Examples of the rubber used for the rubber-modified vinyl aromatic polymer include polybutadiene, styrene-butadiene copolymer, polyisoprene, butadiene-isoprene copolymer, natural rubber, ethylene-propylene copolymer and the like. And particularly preferred are polybutadiene and styrene-butadiene copolymer. As the rubber-modified vinyl aromatic polymer, rubber-modified polystyrene (hereinafter referred to as H
IPS) and a rubber-modified styrene-acrylonitrile copolymer (hereinafter, ABS resin) are preferable.

Examples of the block copolymer comprising a vinyl aromatic polymer block and a conjugated diene polymer block include a styrene-butadiene block copolymer and a styrene-isoprene block copolymer. Further, as an example of a block copolymer comprising a vinyl aromatic polymer block in which part or all of the conjugated diene polymer block is hydrogenated and a conjugated diene polymer block, a part or all of the butadiene portion is hydrogenated An added styrene-butadiene block copolymer, a styrene-isoprene block copolymer in which a part or all of an isoprene portion is hydrogenated, and the like can be given.

The organic phosphorus compounds used in the present invention are phosphate esters known as general phosphorus flame retardants, such as tricresyl phosphate, triphenyl phosphate, cresyl-diphenyl phosphate, and tris (β-
Naphthyl) phosphate, tris (2,3,6-trimethylphenyl) phosphate, and esters composed of bisphenol A and diphenyl phosphate. These organic phosphorus compounds can be used alone or in combination of two or more.

The proportion of the organophosphorus compound varies depending on the proportion of the resin component. If the proportion is too small, the flame retardancy is insufficient. If the proportion is too large, the heat resistance of the resin is impaired. Generally, the amount is 1 to 100 parts by weight, more preferably 3 to 50 parts by weight, and most preferably 5 to 30 parts by weight based on 100 parts by weight of the composition of the polyphenylene ether resin and the polystyrene resin.

The ammonium polyphosphate used in the present invention is a synthetic resin obtained by microencapsulating single ammonium polyphosphate particles. As used herein, the synthetic resin refers to polycarbodiimide, polyurethane, polyisocyanurate, polyurea, melamine / formaldehyde resin, and epoxide resin.

The ammonium polyphosphate is represented by the following formula (3). (NH4PO3) n (3) (where n is 200 to 1000) Ammonium polyphosphate microencapsulated with these synthetic resins can be used alone or in combination of two or more.

If the mixing ratio of the ammonium polyphosphate microencapsulated with the synthetic resin is too small, the dripping prevention during burning is insufficient, and if it is too large, the impact resistance of the resin is impaired. Generally, with respect to 100 parts by weight of a composition of a polyphenylene ether resin and a polystyrene-based resin, 0.5 to 50 parts by weight of ammonium polyphosphate microencapsulated with a synthetic resin is more preferable.
0.7 to 40 parts by weight, most preferably 1 to 3 parts by weight.
0 parts by weight.

The flame-retardant polyphenylene ether-based resin composition of the present invention may contain other additives within the range not impairing the effects of the present invention, for example, ethylene-propylene elastomer, styrene-grafted ethylene-propylene elastomer, thermoplastic polyester elastomer, and ionomer. Impact strength improvers such as resin, core-shell polymer consisting of rubber-like core and non-rubber-like shell, anti-dripping agents such as Teflon, plasticizers, other flame retardants, antioxidants, and stabilizers such as ultraviolet absorbers , A release agent, a dye or pigment, or a fibrous reinforcing agent such as glass fiber and carbon fiber, and a filler such as glass beads, calcium carbonate, and talc may be added.

The method for producing the flame-retardant polyphenylene ether-based resin composition of the present invention is not particularly limited, and may be produced by kneading using a kneading machine such as an extruder, a heating roll, a kneader, and a Banbury mixer. Can be.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. As the organic phosphorus compounds in the examples and comparative examples, the organic phosphorus compounds represented by the following formulas (4) and (5) were used.

[0028]

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[0029]

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In the following Examples and Comparative Examples, the properties of various flame-retarded polyphenylene ether resins were measured and evaluated by the following methods. (A) Flame retardancy: Underwriters Laboratories, Inc. (Underwriters)
Laboratories Inc. , U.S. S. 94A described in 7 to 10 items of "UL94 Safety Standard: Combustion Test of Plastic Materials for Equipment Parts" published by A)
The test was performed using a 1/16 inch test piece on the basis of -2, 94V-1, and 94V-0.

[0031]

Example 1 A polyphenylene ether resin having an intrinsic viscosity [η] of 0.47 as measured in chloroform at 30 ° C.
39 parts by weight of poly-2,6-dimethyl-1,4-phenylene ether (hereinafter abbreviated as PPE), and an impact-resistant polystyrene resin as HIPS [manufactured by Asahi Kasei Corporation:
Trade name: Asahi Kasei Polystyrene 492] 53 parts by weight, polystyrene resin (hereinafter abbreviated as GPPS) [manufactured by Asahi Kasei Kogyo Co., Ltd .: trade name Asahi Kasei Polystyrene 685] 8 parts by weight of a resin composition of 100 parts by weight, 14 parts by weight of the organic phosphorus compound represented by 4) and ammonium polyphosphate microencapsulated with a melamine resin [Hoechst Japan K.K.
462] 1 part by weight was mixed and melt-kneaded with a twin-screw extruder to obtain pellets. 1/16 using these pellets
Inch test specimens were injection molded and evaluated. The results are shown in Table 1.

[0032]

Example 2 Pellets were obtained, molded and evaluated in the same manner as in Example 1, except that 1 part by weight of ammonium polyphosphate microencapsulated with a melamine resin was changed to 5 parts by weight. The results are shown in Table 1.

[0033]

Example 3 Pellets were obtained, molded and evaluated in the same manner as in Example 1, except that the organophosphorus compound was changed to the triphenyl phosphate represented by the above formula (5). 1 is shown.

[0034]

Comparative Example 1 Example 1 was repeated except that ammonium polyphosphate microencapsulated with a melamine resin was changed to ammonium polyphosphate not microencapsulated (Hoechst Japan K.K., trade name: Hostafram AP422).
A pellet was obtained, molded, and evaluated in the same manner as described above, and the results are shown in Table 1.

[0035]

Comparative Example 2 Pellets were obtained and molded in the same manner as in Example 2 except that 5 parts by weight of ammonium polyphosphate microencapsulated with a melamine resin was changed to ammonium polyphosphate not microencapsulated, and evaluation was performed. Table 1 shows the results.

[0036]

Comparative Example 3 Pellets were obtained and molded in the same manner as in Example 1 except that 1 part by weight of ammonium polyphosphate microencapsulated with a melamine resin was changed to 0.3 part by weight.
The evaluation was performed, and the results are shown in Table 1.

[0037]

[Table 1]

[0038]

The flame-retardant polyphenylene ether-based resin composition of the present invention is a resin composition which is more excellent in dropping resistance than a conventional flame-retardant resin composition.

Claims (1)

[Claims] 1. A polyphenylene ether resin (A)
100 parts by weight of a composition of 90 parts by weight and 90 to 10 parts by weight of a polystyrene resin;
A flame-retardant polyphenylene ether-based resin composition comprising 100 parts by weight and 0.5 to 50 parts by weight of ammonium polyphosphate obtained by microencapsulating ammonium polyphosphate particles with (C) a synthetic resin.