JPH0116263B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a flame-retardant ethylene polymer composition having excellent heat resistance at high temperatures. Ethylene-based polymers have excellent electrical insulation properties, and can also be cross-linked by radiation, organic peroxide cross-linking,
It has excellent properties such as the ability to easily improve high-temperature thermal deformability by crosslinking methods such as silane crosslinking using a silane compound as disclosed in the invention described in Japanese Patent Publication No. 1711/1982, and is therefore widely used than before. Although it is used as an electrical insulating material, it has the disadvantage of being flammable. As a method to overcome this drawback, a combination system of a halogen compound as a flame retardant and a heavy metal compound such as antimony trioxide, which is a synergist thereof, has been mainly adopted. However, flame-retardant ethylene polymer compositions containing halogen compounds have the problem of lower heat aging properties compared to flame-retardant ethylene polymer compositions due to the high thermal decomposition properties of the halogen compounds. It was hot. Especially in recent years, in fields such as electrical equipment, vehicles, automobiles, and nuclear power plants, UL-94 V
Insulated wires are required to pass advanced flame retardant tests such as VW-1 of UL-62, but in order to provide such high flame retardancy, large amounts of halogen compounds are required. The heat aging properties of the resulting composition will then be markedly reduced. The present inventors conducted various studies to solve these drawbacks of flame-retardant ethylene polymer compositions, and as a result, as a flame retardant, the general formula: (wherein, m represents 3 or 4. n represents an integer from 1 to 6) and a 3,5-di-tert-butyl-4-hydroxyphenyl group with a molecular weight of 500 or more. When a combination system with an antioxidant having the above-mentioned compound is combined with an antioxidant other than the above-mentioned one, the heat aging resistance of the composition decreases as the amount of the halogen compound increases. In the case of a combination system of a fuel and the above-mentioned antioxidant having a 3,5-di-tert-butyl-4-hydroxyphenyl group with a molecular weight of 500 or more, the resultant composition showed a similar decrease. It has been discovered that the heat aging resistance is improved compared to when only an antioxidant is added, which is a completely new effect. The present invention was completed based on this new knowledge. Ethylene-based polymers here mean polymers whose main raw material is ethylene, such as polyethylene, ethylene/vinyl acetate copolymer, ethylene/ethyl acrylate copolymer, ethylene/propylene copolymer, etc. olefin copolymer,
and ethylene propylene diene terpolymer. In addition, the reason why the amount of the halogen compound represented by the above general formula used in the present invention is set to 5 to 90 parts by weight per 100 parts by weight of the ethylene polymer is that if the amount is less than 5 parts by weight, it will not affect the composition. This is because the effect of imparting flame retardancy is low, and if the amount is more than 90 parts by weight, the mechanical strength such as tensile strength and elongation of the resulting composition will be significantly reduced. Also, the reason why the amount of the antioxidant having a 3,5-di-tert-butyl-4-hydroxyphenyl group with a molecular weight of 500 or more was set at 0.1 to 10 parts by weight per 100 parts by weight of the ethylene polymer. This is because if the amount is less than 0.1 part by weight, the effect of imparting heat aging resistance to the composition is weak, and if it is 10 parts by weight or more, the effect of improving the heat aging resistance of the composition by increasing the amount is slow. General formula used in the present invention, (wherein, (m represents 3 or 4. n represents an integer from 1 to 6).
4,5,6-tetrabromophthalimide, 3,
4,5,6-tetrachlorophthalimide, 3,
4,5,6-tetrabromophthalimidoalkyl, 3,4,5,6-tetrachlorophthalimidoalkyl, N-(3,5-dimethyl-2,4,6
-tribromophenyl)-3,4,5,6-tetrabromophthalimide, N,N'-(1,2-ethylene)-bis[3,4,5,6-tetrabromophthalimide], N,N '-(1,2-ethylene)-bis[3,4,5,6-tetrachlorophthalimide], N,N'-(1,4 and 1,3-phenylene)
-bis[3,4,5,6-tetrabromophthalimide], N,N'-(1,4 and 1,3-phenylene)-bis[3,4,5,6-tetrachlorophthalimide], N, N'-(methylene-di-P-phenylene)-bis[3,4,5,6-tetrabromophthalimide], N,N'-(methylene-di-P-
phenylene)-bis[3,4,5,6-tetrachlorophthalimide], N,N'-oxy-di-P-
phenylene)-bis[3,4,5,6-tetrabromophthalimide], N,N'-(oxy-di-P
-phenylene)-bis[3,4,5,6-tetrachlorophthalimide], N,N'-(2,3,5,
6-tetrachloro-P-xylylene)-bis[3,
4,5,6-tetrachlorophthalimide], N,
N'-(2,4,5,6-tetrachloro-m-xylylene)-bis[3,4,5,6-tetrachlorothalimide], and the like. The compound having a molecular weight of 500 or more and a 3,5-di-t-butyl-4-hydroxyphenyl group used in the present invention includes 1,3,5-tri-methyl-
2,4,6-tris(3,5-di-t-butyl-
4-Hydroxy-benzyl)benzene (Ionox 330 molecular weight 761), hexamethylene glycol-bis[3,5-di-t-butyl-4-hydroxy-phenyl)propionate] (Irganox 259, molecular weight 639), 6-(4- Hydroxy-
3,5-di-t-butylanilino)-2,4-bis-octyl-thio-1,3,5-triazine (Irganox 565, molecular weight 525), tetrakis[methylene-3(3,5-di-t- Butyl-4-hydroxy-phenyl) propionate] methane (Irganox 1010, molecular weight 1177), 2,2-thio[diethyl-bis-3(3,5-di-t-butyl-4-hydroxy-phenyl) propionate] ( Irganox 1035, molecular weight 643), octadecyl-3(3,5-di-t-butyl-4-hydroxy-phenyl)propionate (Irganox 1076, molecular weight 531), N,N'-hexamethylene-bis(3,5- di-t-butyl-4-hydroxy-hydrocinnamamide) (Irganox
1098, molecular weight 637), bis(3,5-di-t-butyl-4-hydroxy-benzoyl phosphoric acid monoethyl ether nickel salt (Irgastav 2002, molecular weight 713), tris(3,5-di-t-butyl-4-hydroxy-benzoyl phosphoric acid monoethyl ether), -butyl-4-hydroxy-phenyl) isocyanurate (Gutudrite 3114, molecular weight 712),
Tris β-(3,5-di-t-butyl-4-hydroxy-phenyl)propionyl-oxyethyl] isocyanurate (Gutudrite 3125, molecular weight 1045), N,N'-bis-3(3,5-di-t −
Butyl-4-hydroxyphenyl) propionic acid hydrazide (molecular weight 553) is generally easily available and effective for improving heat resistance. The product name and molecular weight are written inside the cutlet. In addition, the ethylene polymer composition of the present invention can be produced using a radiation crosslinking method using ionizing radiation, a chemical crosslinking method using an organic peroxide, etc., and a silane polymer composition using a silane compound disclosed in the invention described in Japanese Patent Publication No. 1711/1983. Crosslinking by a crosslinking method such as a crosslinking method is also possible,
Thereby, it is possible to improve the heat deformability of the composition. The composition of the present invention may not only contain a heavy metal compound such as antimony trioxide as a flame retardant synergist, but may also be used in combination with other halogen compound flame retardants as long as the heat aging resistance of the composition is not significantly reduced. It is also possible to use a hydrous inorganic flame retardant such as aluminum hydroxide or magnesium hydroxide in combination within a range that does not reduce the mechanical strength. It is also possible to incorporate ultraviolet absorbers, metal deactivators, colorants, lubricants, stabilizers, reinforcing agents for rubber and plastics, fillers, flame retardants, and flame retardant promoters. Next, the present invention will be explained in detail with reference to Examples. N,N'-(1,4-phenylene)-bis(3,
Preparation of 4,5,6-tetrabromophthalimide) A flask is equipped with a heating mantle and a reflux condenser. In this flask, 10.00 g of tetrabromophthalic anhydride was completely dissolved in 0.5 ml of ethyl methyl ketone, followed by 1.179 phenylene diamine, previously dissolved in 50 ml of ethyl methyl ketone in a separate flask. The mixture was poured and reacted at 80° C. for 16 hours while stirring.
The generated precipitate was filtered and purified by dissolving unreacted substances twice in ethyl methyl ketone at 80°C. The precipitate was heated to 150° C. for 1 hour to complete the condensation reaction. The compound synthesized in this way is a dark brown powder, and its thermal properties do not have a melting point up to 450°C, and decomposition begins at 450°C. The yield was 46%. Examples 1 and 2 Comparative Examples 1 to 10 Compositions having the composition ratios shown in Table 1 were kneaded using an open roll at a material temperature of about 130°C.
Next, press in a high-temperature press at 160℃ for 5 minutes to 1mm.
A thick sheet was obtained. Add a 1Mev electron beam to this
Crosslinking was performed by irradiating 30 Mrad. The properties of the crosslinked sheet thus obtained were evaluated. The evaluation results are also listed in Table 1. In the case of compositions containing ordinary flame retardants such as decabrom diphenyl ether and polyethylene chloride, 4,4'-thio-bis(3-methyl-6-t-butylphenol), which is used as an antioxidant in polyethylene, etc. ) and N,N'-di-β-naphthyl-P-phenylenediamine, which is widely used as an antioxidant for rubber, the heat aging properties are lower than that of the antioxidant alone. It is declining.
The antioxidant is 2,2'-thio[diethyl-bis-3
(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (trade name Irganox
1035), tetrakis [methylene-3(3,5-di-
t-Butyl-4-hydroxy-phenyl)propionate] methane (trade name Irganox 1010)
Even if things change, the situation will not change. On the other hand, N,
N'-(1,4-phenylene)-bis(3,4,5,
6-tetrabromophthalimide) and N,N'-
When using ethylene-bis(3,4,5,6-tetrabromophthalimide), 4,4'-thio-bis(3-methyl-6-t-butylphenol) and N,N'-di-β -When used in combination with naphthyl-P-phenylenediamine, the heat aging properties are lower than when the antioxidant is used alone, but if the antioxidant has a molecular weight of 500 or more,
In the case of Irganox 1035 and Irganox 1010, which have a 4-hydroxyphenyl group, a remarkable improvement in heat aging resistance is observed compared to the case of using only an antioxidant. Just in case, N,N'-(1,4-phenylene)-
bis(3,4,5,6-tetrabromophthalimide) and N,N'-ethylene-bis(3,4,5,
The antioxidant effect of 6-tetrabromophthalimide) was investigated, but no significant antioxidant effect was observed in these compounds. From these facts, the molecular weight
an antioxidant having 500 or more 3,5-di-tert-butyl-4-hydroxyphenyl groups;
N'-(1,4-phenylene)-bis(3,4,5,
A favorable synergistic effect is observed between the halogen compounds such as (6-tetrabromophthalimide),
It was found that the heat aging resistance of ethylene polymers was significantly improved. Example 3, Comparative Examples 13 to 17 Next, the present invention was confirmed on peroxide-crosslinked flame-retardant insulated wires. The compositions having the composition ratios shown in Table 2 were mixed at 5 Banbury. It was formed into a sheet using a roll and pelletized to obtain a pellet-like composition. This was extruded and coated onto a 14AWG copper conductor using a small extruder (30mmφ, L/D22). The material temperature at this time is 100~
It was 110℃. 200 pieces of insulated wire thus obtained
Potassium nitrate, sodium sulfite, sodium nitrate mixture (trade name: Toretsk Tokyo Ohka Co., Ltd.) at °C
The sample was immersed in a tank filled with molten salt and thermally crosslinked for 3 minutes under a nitrogen pressure of 3 kg/cm ² . Its characteristics are also listed in Table-2. This result shows that the favorable property-improving effect of the present invention is not diminished even when antimony trioxide is used in combination. The Example 3 product fully passed the UL-125℃ heat aging test standard, 158℃, 7 days, and also passed the UL-125℃ heat aging test standard.
-62 It has excellent properties that also pass the high flame retardant test VW-1. In other words, the present invention is excellent in that it improves the heat aging resistance of ethylene polymers, enables use at temperatures above 120°C, and also provides excellent flame retardancy, so it has extremely large industrial merits. .

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Claims (1)

[Claims] 1 General formula for 100 parts by weight of ethylene polymer, (wherein, m represents 3 or 4. n represents an integer from 1 to 6.) 5 to 90 parts by weight of a halogen compound represented by 4
- Compounds with hydroxyphenyl group from 0.1 to
A flame-retardant ethylene polymer composition characterized by containing 10 parts by weight. 2 The ethylene polymer is one or two selected from polyethylene, ethylene/vinyl acetate copolymer, ethylene/ethyl acrylate copolymer, ethylene/α-olefin copolymer, and ethylene/propylene/diene terpolymer. The flame-retardant ethylene polymer composition according to claim 1, which is a blend of the above.