JPS5851415A - Flame resistant insulated wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flame-retardant insulated wire, and more particularly to a flame-retardant insulated wire coated with a flame-retardant insulating material suitable for preventing dripping during combustion. be.

Ethylene-based polymers, which have excellent electrical insulation properties, are mainly used as insulating materials for electric wires and cables.

However, in recent years, there has been a strong demand for high flame retardancy at the UL standard VW-I level for cables for nuclear power plants, electric wires for vehicles, motor cords, etc.

One way to make polymers flame retardant is to mix them with chlorine-based or bromine-based compounds, but simply mixing them with them will cause a drip phenomenon in which burning materials melt and fall during combustion, and the UL standard VW - It is difficult to impart a high degree of flame retardancy.

The present invention has been made in view of the above, and its object is to provide a flame-retardant insulated wire that does not cause drips in the insulating material during combustion and has a high degree of flame retardancy.

The present invention' is characterized by adding a small amount of flame retardant, at least 15 parts by weight of chlorine or bromine, to 100 parts by weight of the ethylene polymer, and further adding 0.3 to 1 parts by weight of silicic anhydride.
A conductor was coated with the mixture to which 5 parts by weight was added and then crosslinked to form an insulated wire.

Ethylene polymer, ethylene propylene copolymer,
Ethylene fluorene diene copolymer, polyethylene, ethylene butene copolymer, ethylene vinyl acetate copolymer,
Refers to ethylene ethyl acrylate copolymers, chlorinated polyethylene, etc. alone or in combination.

Examples of compounds containing chlorine or bromine include perchloropentacyclofurcane, hexabromodiphenyl, decabromodiphenyl ether, and the like. The reason why the amount of chlorine or the amount of bromine is set to 15 parts by weight or more is that if it is less than the limited value, it is not possible to provide a high degree of flame retardancy meeting the UL standard VW-Lebel.

Note that antimony trioxide may be used in combination to increase the flame retardant effect. The amount of silicic anhydride is 0.3 to 15
The reason why it is limited to 0.6 parts by weight or less is that dripping during combustion cannot be suppressed, and if it is 15 parts by weight or more, the viscosity of the mixture becomes extremely high and extrudability deteriorates. .

As a crosslinking agent, an organic peroxide represented by dicumyl peroxide is suitable, and it may be used alone or in combination with sulfur or the like as an auxiliary agent.

In addition, if it is necessary to further add an antioxidant, the antioxidant is N,1/-di-β-naphthyl-p-
Amine-based such as phenyl diamine and 4,4'-
Thio-bis-(3methyl-6-t-butylphenol)
and phenolic antioxidants such as 2,6-di-t-butyl-p-cresol. It goes without saying that other than these, lubricants, dispersants, etc. may be added as necessary.

Next, examples and comparative examples of the present invention will be described.

Table 1 shows the formulations and amounts of the flame-retardant insulators in Examples and Comparative Examples, so the amounts are expressed in parts by weight.

The first electric wire was manufactured by kneading the mixture with a 6-inch roll and then using a 40 m/m extruder (with a cylinder temperature of 120°C).
L/D=251 Needle A, copper wire with an outer diameter of 1.7 mm and a thickness of 1.
After coating to 0 m, steam at 16 atm (temperature approx.
5° C.) for 3 minutes.

Table 2 shows test results for flame retardancy and electrical properties of insulated wires using the insulating materials of the Examples and Comparative Examples shown in Table 1.

-4, no drips were observed during combustion,
It passes the tJL standard VW-1 and has a good extruded appearance.

On the other hand, Comparative Examples 5 and 6 did not meet the UL standards VW- and -1 because they did not contain silicic anhydride.

Furthermore, in Comparative Example 7, the amount of silicic anhydride was greater than the limit value of 15 parts by weight, so the flame retardance was passed, but the extrusion appearance was poor due to discoloration.

Note that almost the same effect can be obtained even if anhydrous silicic acid is replaced with hydrated silicic acid.

As described above, according to the embodiments of the present invention, it is possible to obtain an insulated wire that does not produce drips during combustion and has a high degree of flame retardancy that passes UL standard VW-1.
It is suitable as a cable and has extremely large industrial value.

As explained above, according to the present invention, the insulating material does not drip during combustion and has a high degree of flame retardancy.

Claims (1)

[Claims] 1. The conductor was coated with a mixture in which at least 15 parts by weight of chlorine or bromine of a flame retardant was added to 100 parts by weight of ethylene polymer, and 0.6 to 15 parts by weight of silicic anhydride was added. A flame-retardant insulated wire characterized by being post-crosslinked.