JPS6261201A - Flame resisting electric insulation composition - 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 [Industrial Application Field] The present invention relates to a flame-retardant electrical insulating composition for obtaining an electrical insulating material that does not generate halogen gas upon combustion.

[Prior Art] For example, ethylene-based polymers, which have excellent extrusion processability and electrical insulation properties, have been widely used as insulating materials and sheath materials for electric wires and cables.

As a recent trend, there has been a strong demand for flame retardancy for electric wires and cables for nuclear power plants, electric wires for vehicles, and electric wires for wiring inside panels and machines.

The method of making this type of polymer flame retardant has been to mix it with halogen-containing compounds, but these compounds emit a large amount of smoke in the event of a fire, are harmful to the human body, and corrode switches in equipment. The problem is that large amounts of gas are generated.

In light of this situation, attention has been paid to a method of incorporating inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide, which have very low smoke-producing, anti-corrosive properties and low corrosive properties.

[Problems to be solved by the invention However, V T F = D (
In order to provide a high degree of flame retardancy that passes the vertical tray combustion test, it is necessary to add large amounts of these inorganic flame retardants. As a result, not only does this lead to a decrease in dispersion and tensile properties, but even if the oxygen index, which is a measure of the material's flame retardance, is increased, the ash content after combustion is soft and cannot retain its shape.
There is a serious problem of not being able to pass the exam.

The present invention was made in order to solve the above-mentioned problems of the prior art.
The object of the present invention is to provide a novel flame-retardant electrical insulation composition that can pass T.

The flame retardant resin composition of the present invention contains 30 to 30 parts of crystalline hydrated aluminosilicate per 100 parts by weight of polyolefin.
It is characterized by containing 300 parts by weight.

In the present invention, polyolefins include ethylene-propylene copolymer, ethylene-propylene-diene terpolymer, polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate-1~] polymer, and ethylene-butene copolymer. These can be used alone or in combination of two or more.

As hydrated aluminosilicate, Na20-Al103"2Si02-4cho0, K2O
・△1203・2SI02・4[''20, Ca0-A
l2o3' 23! 02 ・4t-(20, Ba0
-Al1 o 3 -2sio2 - 41120
, etc.

These have the effect of releasing the water held in the pores when burned, giving the resin flame retardancy and creating a strong shell that prevents the insulator from being directly exposed to fire. It is considered to have flame retardant properties and pass V.

The content of hydrated aluminosilicate is polyolefin 10
It is necessary to keep the amount in the range of 30 to 300 parts by weight relative to 0 parts by weight. If it is less than 30 parts by weight, sufficient flame retardance cannot be imparted, and if it exceeds 300 parts by weight, it will lead to a significant decrease in physical properties. Become.

In the present invention, in addition to the above components, antioxidants, lubricants, etc. may be added as necessary. Also, when crosslinking a 1q electrical insulator, heating crosslinking by adding 13x peroxide is used. Another example is irradiation crosslinking by irradiation with an electron beam or the like.

[Example] Various ingredients were blended as shown in Table 1, thoroughly kneaded in a 12-inch mold adjusted to 130°C, and then extruded at 40 m/m maintained at 150°C) (1/D = 20), various cables were produced by extrusion coating the outer periphery of three twisted crosslinked polyethylene insulated wire cores with an outer diameter of 3.0 mm to a thickness of 1.5 mm.

The evaluation of the cables obtained in each case is as indicated in each column of Table 1.

In addition, the evaluation is entered as follows:.

Tensile properties: After being left in a constant temperature room at 20'C for 1 day, dumbbell 3
200 mm / 200 mm with a cylindrical tension tester.
Measurements were made at a speed of 11 lin.

Flame retardant: Line up 8 cables 2.4 m long in a vertical lay at intervals of 1/2 the outer diameter, and use the lower end of the goople 60
2cm heat amount 70,000 BTU/hr flame
After 0 minutes of exposure, the burner was extinguished, and if the goople self-extinguished the flame, it passed, and if it burns to a height of 1.8 m or more, it failed.

As is clear from Table 1, in Examples 1 to 5, which fall within the scope of the present invention, sufficiently satisfactory results were obtained in all characteristics.

However, aluminum hydroxide and magnesium hydroxide
Comparative Example 1.2, in which approximately 0.00 parts by weight was blended, failed the VTFT test, and Comparative Example 3, in which the blended amount was increased to 200 parts by weight.
In this case, the tensile properties deteriorate. In Comparative Example 4, which contains hydrated aluminosilicate in an amount greater than the specified value of the present invention, the extrudability and tensile properties deteriorate significantly.

[Effects of the Invention] As explained above, according to the present invention, it is possible to obtain an electrical insulating material that has a high degree of flame retardancy that passes VTFT and does not generate toxic halogen gas when burned. Become.

Claims (1)

[Claims] (1) A flame-retardant electrical insulation composition characterized by containing 30 to 300 parts by weight of crystalline hydrated aluminosilicate per 100 parts by weight of polyolefin.