JPH06283030A - Nonflammable electric insulating composite and insulated wire - Google Patents

Abstract

PURPOSE:To improve the antiabrasive property by mixing a metal hydroxide subjected to surface treating by a silane coupling agent, to a blend of polyolefine and a polyolefine denaturated by an unsatulated carboxylic-acid or its derivative. CONSTITUTION:A silane coupling agent has a functional group reacting with an organic substance, and a group combining with an inorganic substance in its molecules. By subjecting a mixed metal hydroxide to surface treating with the silane coupling agent, the silane coupling agent is combined on the surface of the metal hydroxide. By reacting the functional group in the silane coupling agent combined on the surface with a polyolefine denatulated by an unsatulated carboxylic-acid or its derivative, the metal hydroxide and the polyolefine are combined integrally. As a result, the antiabrasive property can be improved. In this case, the mixing amount of the metal hydroxid is preferred where it is 30 to 150 pts.wt. to 100 pts.wt. of the total of the polyolefine and the polyolefine denaturated by the unsatulated carboxylic-acid or its derivative.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant electrical insulating composition having excellent abrasion resistance and an insulated wire.

[0002]

2. Description of the Related Art In recent years, high performance and high functionality have been rapidly promoted mainly in passenger cars, and along with this, electric and electronic circuits have increased and the enlargement of wire harness has become a problem. For this reason, countermeasures against bloating have been demanded, and as a part of this, the wire harness electric wires have been made thinner and thinner, and now polyvinyl chloride insulated wires are being made thinner and thinner by reducing the core wire diameter and insulating layer. Has become.

[0003]

However, recently, the preservation of the global environment has been attracting attention as a global issue, and recycling of resources and processed products and industrial waste treatment are being promoted globally in a wide range of fields including automobiles. It has come to be taken seriously at the level. For this reason, the generation of corrosive halogen gases during incineration is becoming a problem from the viewpoint of environmental pollution even for polyvinyl chloride used for wire harness wires for automobiles.

Due to such social trends, attention has been paid to non-halogen flame-retardant materials that do not generate halogen-based gas. However, non-halogen flame-retardant materials mixed with metal hydroxides have poor toughness and poor wear resistance as compared with conventional polyvinyl chloride, and are difficult to apply to small-diameter, thin-walled electric wires.

An object of the present invention is to provide a flame-retardant electrically insulating composition and an insulated wire, which are capable of solving the above-mentioned drawbacks of the prior art and greatly improving abrasion resistance.

[0006]

The gist of the present invention is to blend a blend of a polyolefin and a polyolefin modified with an unsaturated carboxylic acid or a derivative thereof with a metal hydroxide surface-treated with a silane coupling agent. is there. Further, 30 to 15 parts by weight of metal hydroxide surface-treated with a silane coupling agent is added to 100 parts by weight of the blend.
It is a flame-retardant electrical insulating composition mixed with 0 parts by weight, and is an insulated electric wire in which the conductor is coated.

[0007]

According to the above structure, the silane coupling agent is
It has a functional group that reacts with organic substances and a group that bonds with inorganic substances in its molecule.By surface-treating a miscible metal hydroxide with a silane coupling agent, silane coupling on the surface of metal hydroxide is possible. The agent is bound, and the functional group of the silane coupling agent bound to the surface of the agent reacts with the polyolefin modified with unsaturated carboxylic acid or its derivative, whereby the metal hydroxide and the polyolefin are bound together. As a result, the wear resistance is greatly improved.

In the present invention, examples of the polyolefin include low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene and polybutene, but polypropylene is preferable. These may be used alone or in combination of two or more.

In the present invention, the polyolefin modified with an unsaturated carboxylic acid or a derivative thereof is a polyolefin which is copolymerized or graft modified by reacting an unsaturated carboxylic acid or a derivative thereof with a polyolefin during or after the polymerization of the polyolefin. As the polyolefin, polyethylene, polypropylene, polybutene, ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer, ethylene methyl acrylate, ethylene propylene rubber, ethylene butene copolymer and the like are used.

Examples of the unsaturated carboxylic acid include acrylic acid, maleic acid, fumaric acid and the like, and derivatives of the unsaturated carboxylic acid include metal salts, amides, esters and anhydrides of the above unsaturated carboxylic acids. Most preferred is maleic anhydride.

In the present invention, the mixing ratio of the polyolefin and the polyolefin modified with the unsaturated carboxylic acid or its derivative is optional, but the weight ratio is 99/1 to 70/30.
Is preferred.

The present invention exhibits a synergistic effect by using a polyolefin modified with an unsaturated carboxylic acid or a derivative thereof and a metal hydroxide surface-treated with a silane coupling agent, and the abrasion resistance is remarkably improved. The present invention has been found out.

Examples of the metal hydroxide include aluminum hydroxide, magnesium hydroxide, hydrotalcite, calcium aluminate, calcium hydroxide, etc. Among them, magnesium hydroxide having the highest flame retarding effect is preferable.

The silane coupling agent for surface treatment is represented by the following chemical formula 1.

[0015]

[Chemical 1]

In the chemical formula 1, R includes vinyl type, methacryloxy type, phenyl type, epoxy type, amino type, mercapto type, and the like, and the vinyl type and methacryloxy type surface treatment effects are particularly remarkable. Vinyl-based silane coupling agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy)
There are silanes and the like, and examples of the methacryloxy type include γ-methacryloxypropyltrimethoxysilane and γ-methacryloxypropyltriethoxysilane.

The amount of the silane coupling agent added is arbitrary, but it is preferably treated in the range of 0.5 to 3% by weight with respect to the metal hydroxide. The surface treatment method of this silane coupling agent is (1) direct addition during compounding. (2) There are two methods of treating the metal hydroxide surface, but the latter is more effective. When surface-treating a metal hydroxide, the silane coupling agent should be dissolved in an organic solvent such as alcohol or diluted with acetic acid water, and then sprayed on the metal hydroxide powder or added to the water slurry. Is common. The metal hydroxide thus surface-treated may be used in combination with another surface treatment, for example, one treated with a fatty acid or a phosphoric acid ester.

The amount of the above metal hydroxide mixed is 30 to 100 parts by weight of the total of the polyolefin and the polyolefin modified with the unsaturated carboxylic acid or its derivative.
It is necessary to use 150 parts by weight, and if the mixing amount is less than the specified value, the desired flame retardancy cannot be imparted, and if it exceeds the specified value, the wear resistance and cold resistance are significantly impaired.

In the present invention, in addition to the above components, a cross-linking agent, an antioxidant, a copper damage inhibitor, a lubricant, a pigment, a nucleating agent, etc. may be added as appropriate, and the composition composed of them is subjected to electron beam irradiation or the like. It may be crosslinked.

[0020]

EXAMPLES Preferred examples of the present invention will be described below together with comparative examples.

Table 1 shows Examples 1 to 6 and Comparative Examples 1 to 4.

[0022]

[Table 1]

According to the compounding ingredients shown in the columns of Examples 1 to 6 and Comparative Examples 1 to 4 in Table 1, 30 m was set at 220 ° C.
knead with a m2 shaft kneader, and then knead the mixture at 220 ° C for 4
A 0 mm extruder was used to extrusion-coat a copper conductor having a core wire outer diameter of 0.87φ with a thickness of 0.20 mm. At this time, the copper conductor was preheated to 130 ° C. with a gas burner.

The electric wires thus produced were evaluated as follows.

(1) Tensile Properties A tubular test piece from which the conductor was removed was measured at a temperature of 23 ° C. and a pulling speed of 200 mm / min.

(2) Abrasion resistance According to Japanese Automotive Standard (JASO) -D608-87,
A wear test by a reciprocating method using a blade under a load of 510 g was conducted at 5 points for each composition, and the number of conductor exposures was examined. Table 1
Shows the minimum value.

(3) Flame retardance According to JASO-D608-87, 300 mm of the sample was supported horizontally, and the afterflame time after applying a reducing flame of Bunsen burner for 10 seconds was measured. It was judged that the afterflame time was within 30 seconds and passed, and that after 30 seconds.

As shown in Table 1, Examples 1 to 1 according to the present invention
It can be seen that each of the samples of No. 6 has excellent wear resistance, tensile properties, and flame retardancy.

On the other hand, in Comparative Examples 1 and 2 in which the mixing amount of the metal hydroxide was out of the limit value, the flame retardancy, elongation and abrasion resistance were remarkably lowered. Further, in Comparative Example 3 in which the polyolefin modified with the unsaturated carboxylic acid or its derivative is not added and Comparative Example 4 in which the metal hydroxide treated with the silane coupling agent is not used, the abrasion resistance is significantly reduced.

[0030]

EFFECTS OF THE INVENTION According to the present invention, a small diameter having excellent wear resistance
This enables the production of thin-walled electric wires, and has the effect of not generating highly corrosive halogen-based gas when incinerated.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location C08L 23/02 LCG 7107-4J 23/26 LDA 7107-4J

Claims (6)

[Claims] 1. A flame-retardant electrical insulating composition comprising a blend of a polyolefin and a polyolefin modified with an unsaturated carboxylic acid or a derivative thereof, and a metal hydroxide surface-treated with a silane coupling agent. . 2. 30 to 30 parts of metal hydroxide surface-treated with a silane coupling agent is added to 100 parts by weight of the blend.
The flame-retardant electrical insulating composition according to claim 1, which is mixed in an amount of 150 parts by weight. 3. The flame-retardant electrical insulating composition according to claim 1, wherein the polyolefin is polypropylene and the unsaturated carboxylic acid or its derivative is maleic anhydride. 4. The flame-retardant electrical insulating composition according to claim 1, wherein the silane coupling agent has a vinyl group or a methacryloxy group in the molecule. 5. The flame-retardant electrical insulating composition according to claim 1, wherein the metal hydroxide is magnesium hydroxide. 6. A conductor is coated with an electrically insulating composition comprising a blend of a polyolefin and a polyolefin modified with an unsaturated carboxylic acid or a derivative thereof and a metal hydroxide surface-treated with a silane coupling agent. Characterized insulated wire.