JPH0995566A - Nonhalogen flame-retardant heat-resistant resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nonhalogen flame-retardant heat-resistant resin compsn. which does not emit a toxic gas when burned and is excellent in flame retardance and resistance to heat aging. SOLUTION: This resin compsn. contains 100 pts.wt. polyolefin, 50-200 pts.wt. metal hydroxide, up to 15 pts.wt. hindered phenol antioxidant, up to 5 pts.wt. bis[2-methyl-4- 3-n-alkyl-(12-14C)-thiopropionyloxy)-5-tert-butylphenyl]sulfide, and up to 5 pts.wt. decamethylenedicarboxylic acid disalicyloylhydrazide.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a non-halogen flame-retardant heat-resistant resin composition which can be used as an insulating material for flame-retardant electric wires / cables, etc. and does not generate a toxic halogen-based gas at the time of combustion, particularly flame retardancy. And a non-halogen flame-retardant heat-resistant resin composition excellent in heat aging resistance.

[0002]

2. Description of the Related Art Polyolefin resins are plastics having excellent electrical characteristics and are widely used especially for insulating materials, but they have a problem that their flame resistance is insufficient. Therefore, a method of mixing a halogen-containing compound as a flame retardant or a method of using a polyolefin resin containing a halogen element has been mainly adopted. These halogen-based flame-retardant compositions generate a large amount of non-combustible halogen-based gas or the like in the event of a fire, thereby blocking ambient oxygen to prevent combustion, and have sufficient flame-retardant properties. However, since a large amount of toxic halogen-based gas is generated, it may interfere with fire extinguishing activities and evacuation activities in the event of a fire, and may cause secondary damage such as corrosion of metal objects such as switchboards and adverse effects on the human body. is there. Therefore, a method is known in which, instead of the halogen-based flame retardant, a non-halogen metal hydroxide such as aluminum hydroxide or magnesium hydroxide is blended as the flame retardant.

[0003]

The flame-retardant resin composition containing the above metal hydroxide utilizes the endothermic action when the hydroxide releases water of crystallization as a flame-retardant effect. Yes, smoke, toxicity and corrosive problems are extremely few. However, since the metal hydroxide has a small flame retardant effect, a drip phenomenon of melting and dropping at the time of combustion is observed and it is difficult to impart a high degree of flame retardancy, simply by blending it in the resin composition. In addition, when a large amount of metal hydroxide is added to obtain a high degree of flame retardancy, there is a problem that the heat resistance is significantly reduced. Therefore, an object of the present invention is to provide a non-halogen flame-retardant heat-resistant resin composition which does not generate a toxic halogen-based gas during combustion and is excellent in flame retardancy and heat aging resistance.

[0004]

The above objects of the present invention are based on 100 parts by weight of a polyolefin, 50 to 200 parts by weight of a metal hydroxide, 15 parts by weight or less of a hindered phenolic antioxidant, 5 parts by weight. Parts of bis [2-methyl-
And characterized in that it contains 4- {3-n- alkyl (C ₁₂ ~C ₁₄₎ thio propionyloxy} -5-t-butylphenyl] sulfide and 5 parts by weight of decamethylene dicarboxylic acid disalicyloylhydrazide It has been found that this is achieved by a non-halogen flame-retardant heat-resistant resin composition.

According to the present invention, a polyolefin composition containing a specific amount of metal hydroxide as a flame retardant is added to the above-mentioned three kinds of compounds, namely, a hindered phenol-based antioxidant (hereinafter referred to as compound A), Bis [2-methyl-4-
{3-n-alkyl (C ₁₂ -C ₁₄₎ thio propionyloxy} (hereinafter referred to as Compound C) -5-t-butylphenyl] sulfide (hereinafter referred to as Compound B) and decamethylene dicarboxylic acid disalicyloylhydrazide By using the above in combination in a specific amount, a non-halogen flame-retardant polyolefin composition having significantly improved heat aging prevention performance and flame retardancy was obtained.

[0006]

The polyolefin used in the composition of the present invention includes ethylene, propylene and butene.
1, pentene-1, hexene-1, heptene-1, 3-
Homopolymers of olefinic hydrocarbon monomers such as methylbutene-1 and 4-methylpentene-1, and these 2
Copolymers of at least one kind of monomer (for example, ethylene-propylene copolymer, ethylene-butene-1 copolymer, etc.), and these olefinic hydrocarbon monomers and a small amount of vinyl ester-based monomers and (meth) acrylate-based monomers Examples thereof include copolymers with monomers (for example, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, etc.). These various polymers can be used alone or as a mixture of two or more kinds.

Examples of the metal hydroxide used as a flame retardant in the composition of the present invention include magnesium hydroxide, aluminum hydroxide, calcium hydroxide and the like. These are fatty acids, fatty acid metal salts, silane coupling agents,
It is preferable to use the one surface-treated with a titanate coupling agent or the like.

The metal hydroxide is used in a proportion of 50 to 200 parts by weight with respect to 100 parts by weight of the polyolefin.
If it is less than 50 parts by weight, the flame retardant properties of the composition are remarkably reduced, and if it exceeds 200 parts by weight, the flame retardant properties are saturated and the mechanical strength such as tensile strength and elongation and the heat aging resistance are remarkably lowered. Therefore, it is not preferable.

As the compound A used in the present invention, various hindered phenolic antioxidants known in the art can be used. For example, 1,3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl)
-S-triazine-2,4,6 (1H, 3H, 5H)-
Trione, tris- (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 4,4'-butylidenebis- (3-methyl-6-t-butylphenol), octadecyl-3- (3,5 -Di-t-butyl-
4-hydroxyphenyl) propionate, pentaerythrityl-tetrakis [4-methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, 2,6-di-t-butyl-4 -Methylphenol, 2,6-di-t-butylphenol, 4-hydroxymethyl-2,6-di-t-butylphenol,
2,4-dimethyl-6-t-butylphenol, 2,
2'-methylene-bis- (4-methyl-6-t-butylphenol), 4,4-butylidene-bis- (2,6-
Di-t-butyl-metacresol), 2,2'-thio-
Bis (4-methyl-6-t-butylphenol), bis (3-methyl-4-hydroxy-5-t-butylbenzyl) sulfide, 3,5-di-t-butyl-4-hydroxybenzyl ether, 1, 6-hexanediol-bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis (n-octylthio) -6- (4-hydroxy-3,5 -Di-t-
Butylanilino) -1,3,5-triazine, N, N '
-Hexamethylenebis (3,5-di-t-butyl-4-
Hydroxy-hydrozinnamamide), 1,3,5-trimethyl-2,4,6-tris- (3,5-di-t-butyl-4-hydroxybenzyl) benzene, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate and the like can be mentioned. .

Bis [2-methyl-4- {3-n-alkyl (C ₁₂ -C ₁₄ ) thiopropionyloxy} -5-t-
“Alkyl (C ₁₂ -C ₁₄ )” in butylphenyl] sulfide (Compound B) represents an alkyl group having 12 to 14 carbon atoms, and Compound B alone or a mixture thereof having an alkyl group having 12 to 14 carbon atoms. Either is fine. Specifically, ADEKA STAB AO-23 {Asahi Denka Kogyo Co., Ltd.
Manufactured} can be preferably used.

In the present invention, the amount of the compound A is 15 parts by weight or less, preferably 0.1, based on 100 parts by weight of the polyolefin.
-10 parts by weight, compound B is 5 parts by weight or less, preferably 0.
1 to 3 parts by weight, the compound C is 5 parts by weight or less, preferably 0.
Contains 1 to 3 parts by weight. When the three kinds of compounds A, B and C are used outside the above specified amount ranges, the synergistic effect of these three kinds of compounds is not sufficiently obtained, and excellent heat aging resistance and flame retardancy are obtained. Absent.

In the present invention, the polyolefin 100 is further included.
By adding 1 to 15 parts by weight, preferably 2 to 10 parts by weight of zinc oxide to parts by weight, the compound A,
The synergistic effect of B and C is exhibited more favorably, and a particularly excellent heat aging prevention function is exhibited. Here, when the content of zinc oxide exceeds 15 parts by weight, the heat aging performance reaches saturation,
It is not preferable because it lowers mechanical properties and other properties.

The composition of the present invention comprises a crosslinking aid, an antioxidant, a lubricant, an ultraviolet absorber, a metal deactivator, a colorant, a stabilizer, a rubber / plastic reinforcing agent, and an inorganic filler which are commonly used in this field. Agents, flame retardants and the like can be added.

The flame-retardant heat-resistant resin composition of the present invention appropriately uses a crosslinking method known in the art such as a method of heating in the presence of an organic peroxide and a method of irradiating with ionizing radiation such as an electron beam. And can be crosslinked.

[0015]

EXAMPLES The present invention will now be illustrated by examples.

Examples 1 to 6 and Comparative Examples 1 to 9 The resin compositions having the composition ratios shown in Table 1 were uniformly kneaded with an open roll at 150 ° C., and then the calculated cross-sectional area was measured using a small extruder. Thickness ± 0.5 mm ² (outer diameter 1.0 mm) on a copper conductor
It was extrusion-coated to 0.3 mm to obtain an insulated electric wire.

The materials used will be described below. LDPE: Low density polyethylene (Density: 0.924, M
I: 0.25) HDPE ... High-density polyethylene (Density: 0.949, M
I: 0.30) EEA ... Ethylene-ethyl acrylate copolymer (EA content: 15% by weight, MI: 0.75) Metal hydroxide ... Magnesium hydroxide Compound A ... ADEKA STAB AO-18 (trade name), Asahi Denka Kogyo ( Compound B: Adeka Stab AO-23 (trade name), Asahi Denka Co., Ltd. Compound C: decamethylenedicarboxylic acid disalicyloyl hydrazide lubricant: stearic acid

[0018]

[Table 1]

The characteristics of each of the obtained insulated wires were evaluated, and the results are also shown in Table 1. From the results shown in Table 1, when the addition amount of the metal hydroxide is smaller than the amount specified in the present invention as compared with Example 1 in which the metal hydroxide is contained within the range specified in the present invention (Comparative Example 1 It is understood that the flame retardancy is remarkably lowered in (), and the initial elongation is lowered and the heat aging resistance is remarkably inferior when the addition amount is large (Comparative Example 2). In addition, compound A,
When three kinds of B and C are not used together (Comparative Examples 3 to 8), the heat aging resistance is lowered. Further, when the compounds A, B and C are used in combination in the addition amount of the specific amount of the present invention or more (Comparative Example 9), the flame retardancy is lowered.

On the other hand, by using the compounds A, B and C together in an addition amount within the specified amount range of the present invention (Examples 1 to 6), both flame retardancy and heat resistance were excellent. An insulated wire is obtained. Particularly, by using zinc oxide together (Example 2), the heat aging resistance is further improved while the flame retardancy is sufficiently maintained.

[0021]

EFFECTS OF THE INVENTION By using the composition of the present invention, it is possible to obtain a flame-retardant product which is extremely excellent in flame retardancy and heat aging resistance and does not generate toxic halogen-based gas during combustion.
In particular, when used as an electric insulating material such as a wire coating, it is possible to obtain a flame-retardant electric wire / cable that can be continuously used at high temperature for a long period of time. Furthermore, by using zinc oxide together,
The heat aging resistance can be significantly improved while maintaining sufficient flame retardancy.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01B 7/34 H01B 7/34 B

Claims (2)

[Claims] 1. With respect to 100 parts by weight of polyolefin,
50 to 200 parts by weight of metal hydroxide, 15 parts by weight or less of the hindered phenolic antioxidant, 5 parts by weight or less of bis [2-methyl-4-{3-n-alkyl (C ₁₂ ~
A non-halogen flame-retardant heat-resistant resin composition comprising C ₁₄ ) thiopropionyloxy} -5-t-butylphenyl] sulfide and 5 parts by weight or less of decamethylenedicarboxylic acid disalicyloyl hydrazide. 2. The non-halogen flame-retardant heat-resistant resin composition according to claim 1, which further contains 1 to 15 parts by weight of zinc oxide.