JPH06228369A - Carbon dioxide resistant, flame-retardant composition and electric wire and cable produced therefrom - Google Patents

Abstract

PURPOSE:To provide a compsn. which is excellent in the resistance to carbon dioxide and does not release a hydrogen halide gas during burning, and to provide electric wire and cable produced therefrom. CONSTITUTION:The compsn. is prepd. by compounding 100 pts.wt. thermoplastic resin or rubber with 50-150 pts.wt. magnesium hydroxide surface-treated with a posphoric ester and 1-20 pts.wt. linear low-density polyethylene modified with maleic anhydride. Electric wire and cable with a covering layer comprising the compsn. is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant composition which has excellent carbonic acid resistance and does not generate hydrogen halide gas during combustion, and electric wires and cables using the flame-retardant composition.

[0002]

2. Description of the Related Art As an insulating material for electric wires, cables, and the like, various flame-retardant compositions having flame-retardant properties and not generating hydrogen halide during combustion have been developed. For example, Japanese Patent Laid-Open No. 3-
41132 discloses a flame-retardant composition obtained by adding 10 to 250 parts by weight of a hydrate of an inorganic metal compound surface-treated with a phosphate ester to 100 parts by weight of a polyolefin resin. This composition improves the carbonic acid resistance by surface-treating a hydrate of an inorganic metal compound with a phosphoric acid ester.

[0003]

In such a composition, surface-treated magnesium hydroxide is often used as a metal hydrate. Since magnesium hydroxide is a basic substance, if left in high-humidity air, magnesium carbonate that reacts with carbon dioxide gas in the air and magnesium hydroxide will precipitate on the surface of the material, or if immersed in an acidic solution, magnesium hydroxide will Surface treatment is applied due to the problem of elution, but when this composition is actually used, it is often used in a more harsh environment.In such a case, surface treated water is used. Even if magnesium oxide is used, there is a problem that magnesium carbonate or the like is deposited.

[0004]

The present invention solves the above problems and provides a carbonic acid resistant flame retardant composition having excellent carbonic acid resistance, and an electric wire and a cable using the same. The first feature is 100 parts by weight of thermoplastic resin or rubber, and magnesium hydroxide surface-treated with phosphate ester.
A carbonic acid resistant flame-retardant composition comprising 50 to 150 parts by weight and 1 to 20 parts by weight of maleic anhydride-modified linear low-density polyethylene. The second feature is to provide a coating layer of the composition. There are electric wires and cables on the wire.

[0005]

[Function] Although the mechanism is unknown, by adding maleic anhydride linear low-density polyethylene, the compatibility of the thermoplastic resin or rubber with magnesium hydroxide is improved, and the thermoplastic resin or rubber becomes water-soluble. It is thought that this is because the magnesium oxide comes to be wrapped up cleanly and the contact of magnesium hydroxide with the external atmosphere is cut off.

[0006]

[Examples] Various materials shown in Tables 1 and 2 were kneaded with an open roll for 15 minutes, and a sheet having a thickness of about 1 mm x 13 cm x 17 cm was pressure-molded at about 160 ° C for 10 minutes to prepare a sheet. As a sample to compare carbon dioxide resistance, width 2 cm x thickness 1 mm
A strip-shaped sample of 13 cm is punched out from the above sheet and the humidity is 90%.
% Carbon dioxide gas with a purity of 100% in a desiccator of 200% or more
It was poured at a rate of cc / min and the weight change after 48 hours was measured.

The flame retardancy was measured according to JIS K7201 oxygen index method. It is preferable that the index is 24 or more.
In addition, in order to measure the workability, the melt index is measured by JI.
According to SK6760, it was measured at 190 ° C. and 2160 g. The value is preferably 0.1 or more.

[0008]

[Table 1]

[0009]

[Table 2]

Examples 1 to 5 show the carbonic acid resistance and the increase in weight.
It was as low as 0.5 to 1.2% by weight, and the precipitation of white magnesium carbonate on the surface was small. Further, there was no problem in flame retardancy and processability.

In Comparative Example 1, maleic anhydride-modified linear low-density polyethylene was not added, but the weight increase was large and a large amount of white magnesium carbonate was deposited. In Comparative Example 2, 25 parts by weight of maleic anhydride-modified linear low-density polyethylene was added, and the carbonic acid resistance was good, but the processability was extremely poor. In Comparative Examples 3 and 4, magnesium hydroxide was added in an amount of 45 parts by weight and 155 parts by weight, respectively, but Comparative Example 3 was flame-retardant and Comparative Example 4 was poor in processability. In Comparative Examples 5 to 8, another maleic anhydride-modified substance was added in place of the maleic anhydride-modified linear low-density polyethylene, but all of them had very poor carbonic acid resistance.

The above shows the case where ethylene ethyl acrylate (EEA) is used as an example, but ethylene propylene rubber, acrylic rubber, ultra low density polyethylene, linear low density polyethylene, ethylene vinyl acetate, ethylene methacrylate, Equivalent effects were observed for rubber such as ethylene methyl methacrylate, plastic materials, and mixtures thereof, and these flame-retardant compositions to which maleic anhydride-modified linear low-density polyethylene was added have carbonic acid resistance. It turned out to be excellent.

[0013]

As described above, according to the present invention, it is possible to obtain a carbonic acid resistant flame retardant composition which is excellent in carbonic acid resistance and does not generate hydrogen halide gas during combustion.

Claims (2)

[Claims] 1. Magnesium hydroxide surface-treated with phosphoric acid ester per 100 parts by weight of thermoplastic resin or rubber
A carbonic acid resistant flame-retardant composition comprising 50 to 150 parts by weight and 1 to 20 parts by weight of maleic anhydride-modified linear low-density polyethylene. 2. An electric wire or cable comprising a coating layer of the carbonate resistant flame retardant composition according to claim 1.