JPH07247402A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To obtain a flame-retardant resin composition which comprises a styrenic resin, red phosphorus, a blowing agent of high temperature decomposition type and a silane coupling agent, thus is useful in household appliances, OA appliances and automotive part items because it causes no generation of corrosive or toxic gas and has good balance between its fluidity and shock resistance. CONSTITUTION:This resin composition comprises (A) 100 pts.wt. of a styrenic resin such as HI polystyrene, ABS resin, (B) 10 to 55, preferably 15 to 40 pts.wt. of red phosphorus or a phosphorus flame retardant, (C) 0.2 to 10 pts.wt. preferably 1 to 5 pts.wt. of a high-temperature decomposition type foaming agent, preferably decomposing above 200 deg.C, for example, azodicarbon-amide, N,N'- dinitrosopentamethylenetetramine, 5,5'-bis-1H-tetrazole manganese salt and (D) 0.2 to 5 pts.wt., preferably 0.5 to 2 pts.wt. of a silane coupling agent (preferably having vinyl or methacryl groups, for example, vinyl trimethoxysilane, vinyl triethoxysilane, gamma-methacryloxy propyl methoxy silane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition which does not generate corrosive or toxic gases and has a good balance between fluidity and impact resistance.

[0002]

2. Description of the Related Art Styrenic resins such as HI polystyrene and ABS resins are widely used as housing materials in the fields of home electric appliances and office automation equipment. As a flame retardant for these styrene resins, a halogen flame retardant represented by decabromodiphenyl ether was blended. In recent years, a toxic gas problem caused by flame retardants has been raised, and improvement thereof is strongly demanded. As a method of solving this, for example, a method of compounding a water-containing inorganic compound such as magnesium hydroxide or aluminum hydroxide (JP-A-53-92855,
JP 54-29350 JP, JP 54-77658 JP, JP Sho
57-87462, JP-A-60-110738, etc.) or a method of using ammonium polyphosphate in combination with a nitrogen-containing compound or a polyhydric alcohol (JP-A-52-146452, JP-A-56-53151). Etc.) are proposed.

[0003]

However, in any of the above methods, it is necessary to add a large amount of a flame retardant in order to impart a high degree of flame retardancy, and as a result, moldability and mechanical strength decrease. There was a problem of doing.

The present invention has been made in view of such circumstances, and provides a flame-retardant resin composition which does not generate corrosive or toxic gases and has a good balance between fluidity and impact resistance. The purpose is to provide.

[0005]

As a result of intensive studies, the present inventors have found that the above object can be achieved by incorporating a specific foaming agent, and the present invention has been completed based on this finding. Came to do. That is, the present invention provides a flame-retardant resin composition comprising (A) styrene-based resin, (B) red phosphorus and / or phosphorus-based flame retardant, (C) high temperature decomposable foaming agent and (D) silane coupling agent. It is provided. Hereinafter, the present invention will be specifically described.

The styrene resin (A) in the present invention is
It is a resin obtained by grafting at least one kind of monomers such as styrene and acrylonitrile onto a rubber component such as polybutadiene. Specific examples of these are:
Examples include HI polystyrene, ABS resin, MBS resin, ACS resin, AAS resin and AES resin.

The red phosphorus and phosphorus-based flame retardants (B) of the present invention are widely used as flame retardants for synthetic resins. Specific examples of the phosphorus-based flame retardants include ammonium phosphate, ammonium polyphosphate, tricresyl phosphate (TCP), triethyl phosphate (TEP), tris (β-chloroethyl) phosphate (TCEP), trischloroethyl phosphate (CLP). ), Trisdichloropropyl phosphate (C
RP), cresyl diphenyl phosphate (CDP),
Examples include xylenyl diphenyl phosphate (XDP), acidic phosphoric acid esters, nitrogen-containing phosphorus compounds and the like. These flame retardants may be used alone or in combination of two or more.

The total amount of red phosphorus and / or phosphorus flame retardant compounded with 100 parts by weight of the styrene resin in the present invention is 10 to 55 parts by weight, preferably 15 to 55 parts by weight, more preferably 15 parts by weight. ~ 40 parts by weight. If the blending amount of the flame retardant is less than 10 parts by weight, the flame retardancy becomes insufficient. On the other hand, if it exceeds 55 parts by weight, mechanical strength such as impact strength is lowered.

The high temperature decomposition type foaming agent (C) in the present invention is a foaming agent having a decomposition temperature of 180 ° C. or higher, and particularly preferably 200 ° C. or higher. Preferred specific examples include azodicarbonamide (ADCA), N, N′-dinitrosopentamethylenetetramine (DPT), and a manganese salt of 5,5′-bis-1H tetrazole.

The blending ratio of the high temperature blowing agent to 100 parts by weight of the styrene resin in the present invention is 0.2 to 10 parts by weight, preferably 1 to 10 parts by weight, more preferably 1 to 5 parts by weight. If the blending amount of the high temperature foaming agent is less than 0.2 parts by weight, the flame retardant will bleed. On the other hand, if the amount exceeds 10 parts by weight, the flame retardancy decreases.

The silane coupling agent (D) in the present invention has a general formula of R-Si (OR ') ₃ or R ₂ -Si.
It is a silane compound represented by (OR ′) ₂ . (In the formula,
R represents a vinyl group, an epoxy group, an amino group or a methacryl group, and R'represents an alkyl group such as a methyl group, an ethyl group or a propyl group). Among these, those having a vinyl group or a methacrylic group are preferable. As a specific example,
Examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane.

The blending ratio of the silane coupling agent to 100 parts by weight of the styrene resin in the present invention is 0.2-.
It is 5 parts by weight, preferably 0.3 to 3 parts by weight, and more preferably 0.5 to 2 parts by weight. If the blending ratio of the silane coupling agent is less than 0.2 parts by weight, the flame retardant will bleed. On the other hand, if the amount exceeds 5 parts by weight, the flame retardancy decreases, which is not preferable.

Further, the resin composition of the present invention may optionally contain various conventional additives such as stabilizers, plasticizers, lubricants,
Pigments, fillers and the like can be added.

[0014]

EXAMPLES The present invention will now be described in more detail with reference to examples. The melt rate (hereinafter referred to as “MFR”) is in accordance with JIS K7210, and the temperature is 200 ° C.
It was measured under the condition of a load of 5 kg. Izod impact strength is A
According to STM D256, it was measured at a temperature of 23 ° C. and with a notch. Flame retardance complies with UL94 law, thickness 3m
m test pieces were used.

The styrene resin has an MFR of 1
3g / 10min HI polystyrene (Showa Denko KK,
Esbright 500A) was used. As red phosphorus, Hishigad Master (trade name, manufactured by Nippon Kagaku Kogyo Co., Ltd.)
M ”), Exorit 422 as a phosphorus-based flame retardant
A mixture of 3 parts (trade name, manufactured by Hoechst) and 2 parts pentalit (trade name, manufactured by Koei Chemical Co., Ltd.) (hereinafter referred to as “APE”), Hostflam AP745 (trade name, manufactured by Hoechst) (hereinafter “IFR”) Amguard NP (trade name, manufactured by Albright & Wilson Limited) (hereinafter referred to as “ENP”) and Amgard NK (trade name, manufactured by Albright & Wilson Limited) (hereinafter referred to as “EN”).
K ”) was used. Azodicarbonamide was used as a foaming agent, and γ-methacryloxypropyltrimethoxysilane was used as a silane coupling agent.

Examples 1 to 5 and Comparative Examples 1 to 5 Styrene-based resins whose types and amounts are shown in Table 1, red phosphorus, phosphorus-based flame retardants, foaming agents and silane coupling agents, and octadecyl as a stabilizer. -3-
0.2 parts by weight of (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate was mixed in a Henschel mixer, and then mixed with a twin screw extruder having a diameter of 30 mm to 190.
The mixture was kneaded at 0 ° C to form pellets. A test piece was prepared from each of the obtained pellets by using an injection molding machine. M for each test piece
FR, Izod impact strength and flame retardancy were measured. The results obtained are shown in Table 1.

[0017]

[Table 1]

[0018]

The flame-retardant resin composition of the present invention does not generate corrosive or toxic gases and has a good balance between fluidity and impact resistance. It is useful in fields such as automobile parts.

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Claims (2)

[Claims] 1. A flame-retardant resin composition comprising (A) styrene resin, (B) red phosphorus and / or phosphorus flame retardant, (C) high temperature decomposable foaming agent and (D) silane coupling agent. 2. The amount of (B) is 100 parts by weight of (A).
The flame-retardant resin composition according to claim 1, which comprises 10 to 55 parts by weight of the component, 0.2 to 10 parts by weight of the component (C) and 0.2 to 5 parts by weight of the component (D).