JPS61252255A - Flame-retardant polyethylene resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which is non-dripping has excellent mechanical and electrical characteristics, can be injection-molded and is suitable for use as an electrical insulating material, consisting of PE, chlorinated PE, Sb2O3, a metal hydroxide, a stabilizer and optionally a chlorinated paraffin. CONSTITUTION:100pts.(wt.; the same applies hereinbelow) mixture of 40-60pts. high-density or medium-density PE having an MI of 5 or above, a tensile strength of 200kg/cm<2> or above and an elongation of 60% or above and 60-40pts. chlorinated PE having a chlorine content of 30% or above, a tensile strength of 120kg/cm<2> or above and an elongation of 500% or above, 10-25pts. Sb2O3, 20-35pts. hydroxide of Al, Mg, Zr or Co or mixture thereof, 1-6pts. a least one stabilizer selected from among lead stabilizers and metallic soaps and optionally, 5-15pts. chlorinated paraffin are blended in such a proportion as to give a compsn. having a chlorine content of 10-15%.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to injection moldable, non-dripping, flame-retardant polyethylene compositions having electrical insulation applications and having improved mechanical and electrical properties. BACKGROUND OF THE INVENTION Polyethylene is widely used as an electrically insulating resin because it has excellent properties such as processability and electrical properties. However, since polyethylene is flammable, it has been desired to develop a polyethylene composition that is flame retardant and does not impair the excellent mechanical and electrical properties inherent to polyethylene.

A method for obtaining a flame-retardant resin composition by mixing polyethylene with chlorinated polyethylene and antimony trioxide is known, but when trying to obtain sufficient flame retardance with this composition, not only does moldability deteriorate, but also However, the tracking resistance and mechanical properties were also deteriorated, making it unsuitable for electrical insulation purposes.

Problems to be Solved by the Invention The present invention seeks to provide a polyethylene resin composition that provides a high degree of flame retardancy at the V-O level in the UL94 vertical test and has excellent processability, mechanical properties, and electrical properties. It is something to do.

Means for Solving the Problems The present invention utilizes polyethylene and chlorinated polyethylene.
By blending 1 part by weight of 10 to 25 parts of antimony trioxide, 20 to 35 parts by weight of the metal hydroxide, and 1 to 6 parts by weight of the stabilizer to 100 parts by weight of the mixture of the two. We have succeeded in obtaining a polyethylene composition that satisfies the above properties.

The polyethylene used in the present invention is a high-density or medium-density polyethylene having properties of MI5 or higher, tensile strength of 200 kg/crn2 or higher, and elongation of 1600X or higher. In addition, as chlorinated polyethylene, the chlorine content is 30
% or more, tensile strength of 120 kg/cTL2 or more, and elongation of 45ooX or more.

Materials having these characteristics can be appropriately selected from commercially available products. Metal hydroxides include Al(QH)s, Kg
(OH)2, Z r (OH)4, Co(OH)t and mixtures of one or more of these can be used in predetermined amounts, but Al! Preferably, a mixture of (OH)s and Mg(OH)2 is used. The invention further uses stabilizers.

As stabilizers, stabilizers for vinyl chloride resin, lead-based stabilizers, metal soaps, organic tin compounds, epoxy compounds, etc., and mixtures of two or more of these can be used, but lead-based stabilizers, such as lead phthalate, can be used. It is effective to use one or a mixture of two or more of lead stearate, lead stearate, and the like.

In addition, antioxidants, ultraviolet absorbers, chlorinated paraffins, lubricants, pigments, etc. can be added to the composition of the present invention as required.

In the composition of the present invention, the chlorine content is 10 to 10% of the total weight of the composition.
Each component is blended so that the amount is 15%, preferably 18 to 14%. Thickness 2 if chlorine content is lower than this range
A non-drip flame retardant effect cannot be expected in the UL flame resistance test conducted in our home, and if the temperature is too high, sufficient tracking resistance cannot be obtained. If the chlorine content in the composition of the present invention cannot reach the desired value with chlorinated polyethylene alone, an appropriate amount of chlorinated paraffin can be blended.

The metal hydroxide is necessary to improve the flame retardancy of the resin composition and to impart anti-tracking properties. however,
If the amount of metal hydroxide is high, the mechanical properties of the resin composition will deteriorate.

In addition, stabilizers are necessary for stabilizing chlorine-containing components during heat processing of resin compositions, especially during molding, but if too much is used, the flame retardance and mechanical strength of the resin composition will be significantly reduced. Become.

The present invention achieves V-O in the UL94 vertical test by blending specific amounts of each component with polyethylene as described above.
To develop a resin composition for electrical insulation that not only has a high degree of flame retardancy, but also has sufficiently satisfactory mechanical properties such as tensile strength and electrical properties such as tracking resistance. It was very successful. The composition of the present invention is particularly suitable for use in high voltage insulating covers or construction protection pipes used for the purpose of insulating detent clamps, connectors, sleeves, terminals of insulated wires, etc. of high voltage overhead power lines, linear wires, Products for this purpose fully meet the flame retardancy, processability, mechanical properties, and electrical properties required for electrically insulating polyethylene resin compositions such as insulating protective equipment such as insulator covers and sheets. molded and used.

Examples of the present invention and comparative examples are shown in the table below.

The components shown in the same table are as follows.

Polyethylene 2PE Hi-Zex 20100J (Mitsui Oil) Chlorinated polyethylene: Chlorinated PE Elasthrene 5o3B (
Showa Denko) Chlorinated paraffin: Chlorinated paraffin Empara 70 (Ajinomoto) Antioxidant antioxidant Seenox 401P (Shipro Kasei) Antioxidant Seenox 412S (Shipro Kasei) Ultraviolet absorber: Ultraviolet absorber Ji-Sorb 102 ( Cipro Kasei) Ultraviolet absorber G-SOAP 703 (Cipro Kasei) Carbon: Carbon (Mitsubishi Kasei) Patent applicant Taito Denzai Co., Ltd. (5 others)

Claims (1)

[Scope of Claims] 1) Polyethylene and chlorinated polyethylene each containing 40 to 6
0 parts by weight, total 100 parts by weight, antimony trioxide 10~
A flame-retardant polyethylene resin composition comprising 25 parts by weight of a metal hydroxide, 20 to 35 parts by weight of a metal hydroxide, and 1 to 6 parts by weight of a stabilizer. 2) 40 to 6 each of polyethylene and chlorinated polyethylene
0 parts by weight, total 100 parts by weight, antimony trioxide 10~
25 parts by weight, metal hydroxide 20-35 parts by weight, stabilizer 1
~6 parts by weight and 5 to 15 parts by weight of chlorinated paraffin.