JPH0253846A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having excellent scratch resistance, abrasion resistance, etc., and suitable as a covering material for electric cable, etc., by compounding inorganic compound powder to a mixture of a polyolefin resin and a thermoplastic elastomer added with a specific dibasic acid. CONSTITUTION:The objective resin composition is produced by compounding (A) 100 pts.wt. of a resin mixture consisting of (i) 40-98 pts.wt. of a polyolefin resin (e.g., ethylene-alpha-olefin copolymer) and (ii) 2-60 pts.wt. of a thermoplastic elastomer added with maleic acid (anhydride) and/or phthalic acid (anhydride) (the amount of added dibasic acid is preferably 0.1-5wt.%) with (B) 1-200 pts.wt. of inorganic compound powder. A flame-retardant effect can be also attained by using magnesium hydroxide, aluminum hydroxide, magnesium carbonate, antimony trioxide, etc., as the component B.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a resin composition having excellent trauma resistance, abrasion resistance, tensile properties, etc., particularly as a coating material for electric wires, cables, etc.

[Conventional technology]

Conventionally, polyolefin resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-propylene copolymer are used as base polymers, and calcium carbonate, aluminum oxide, etc. BACKGROUND ART Resin compositions prepared by appropriately adding inorganic fillers are used as insulators for electric wires, cables, etc., and coating materials for sheaths and the like.

[Problem to be solved by the invention]

However, resin compositions using this polyolefin resin as a base polymer have disadvantages in that they are inferior in trauma resistance, abrasion resistance, and tensile properties.

In order to solve these drawbacks, tough polymers such as thermoplastic polyester elastomers have been developed in recent years, but these new polymers require high extrusion temperatures and have similar problems when inorganic fillers are added. However, it has disadvantages such as loss of its excellent LC trauma resistance, abrasion resistance, and tensile properties, and has not been put into practical use.

[Means to solve the problem]

In this invention, the base polymer is a resin mixture in which a polyolefin resin is mixed with a thermoplastic elastomer containing one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride in the molecule. I tried to solve the above problem.

The present invention will be explained in detail below.

The resin composition of this invention has a polyolefin resin of 40 to
A resin mixture consisting of 98 parts by weight and 2 to 60 parts of a thermoplastic elastomer to which one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride is added in the molecule is used as a base polymer, and this Base polymer 10
It is made by blending 1 to 200 parts of inorganic compound powder to 0 parts by weight.

In this invention, the polyolefin resins include homopolymers of A-refins such as polyethylene, polypropylene, poly-1-butene, polypropylene, and poly-4-methyl-1-pentene, and ethylene-edyl acrylate copolymers (EEA ), Eblene-vinyl acetate co-11 polymer (EVA), ethylene-propylene copolymer ([PR)
, ■ Diremp [1 pyrene-di-I-nin] ξ polymer (EP
DM), a copolymer containing an olefin monomer such as ethylene-butene-1 copolymer as a comonomer, and a mixture of two or more of these.

In addition, examples of thermoplastic exmers containing one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride in the molecule include styrene, ethylene,
A block polymer or random copolymer consisting of one polymer such as butylene or propylene/i is used, and one or more of these dibasic acids are added. G1901
Xj (product name, manufactured by Shell Chemical), “Toughtic M191
1°M1913. M1943. M1953J (Product name.

(manufactured by Fukkasei), Tafmer MA8510. Examples include Gutsdomar (manufactured by Mikata Petrochemical). The amount of dibasic acid such as maleic acid added is preferably about 0.1 to 5% by weight. Thermoplastic elastomers in which one of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride is added to the molecule are carbonyl groups of carboxylic acid residues branched from the molecular chain. The metal atoms in the inorganic compound powder form weak bonds such as hydrogen bonds, forming a type of crosslinked structure, and this pseudo-crosslinking increases the cohesive force of the base polymer itself, making it harder and more resistant to external damage. Abrasion resistance etc. are improved. In this crosslinked structure, the bonding strength decreases at n12 degrees when the resin is melted, the molten viscosity does not become high, and the extrusion processability does not deteriorate.

In addition, the blending ratio of polyolefin resin and thermoplastic elastomer with one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride added to the molecule is 40 to 98% of the polyolefin resin. 1 to 72 to 60 parts of the thermoplastic elastomer. If the amount of thermoplastic elastomer is less than 2 parts by weight, no blending effect will be obtained, and if it exceeds 60 parts by weight, processability will deteriorate, which is disadvantageous.

Inorganic compounds are used as base polymers made of such polyolefin resins and thermoplastic elastomers containing one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride in the molecule. Powder is blended. Examples of the inorganic compound powder include magnesium compounds such as magnesium oxide, magnesium hydroxide, and magnesium carbonate; aluminum compounds such as aluminum oxide, aluminum silicate, and aluminum hydroxide;
Calcium compounds such as calcium carbonate and calcium hydroxide, zinc compounds such as zinc oxide and zinc carbonate, lead compounds such as lead oxide and basic lead carbonate, molybdenum compounds such as molybdenum disulfide, butane oxide, potassium titanate, etc. A powdered inorganic compound containing a metal element such as a titanium compound, an antimony compound such as antimony dioxide, or a mixture of two or more is used.The amount of this inorganic compound powder is based on 100 parts by weight of the base polymer. 1
-200 parts by weight, and less than 1 part by weight of a thermoplastic elastomer containing at least one of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride in the molecule. If the amount exceeds 200 parts by weight, the tensile strength and elongation will be low, which is not preferable. This inorganic compound powder also exhibits a filling effect similar to that of ordinary inorganic fillers, and if magnesium hydroxide, aluminum hydroxide, magnesium carbonate, antimony trioxide, etc. are used, a flame retardant effect can also be obtained at the same time.

This resin composition is kneaded using a mixing device such as a high-speed mixer or various cross-mixing devices, and then molded into a desired shape using an extrusion molding machine or an injection molding machine, such as an insulator or a sheath.

In such resin compositions, despite the inclusion of a large amount of inorganic compounds, the composition itself becomes hard and has poor trauma resistance and
Improves wear resistance. Furthermore, since the above-mentioned pseudo-crosslinked structure is eliminated during melting, the melt viscosity does not increase, and it is not necessary to unnecessarily increase the extrusion temperature, etc., and molding can be easily carried out.

〔Example〕

A resin composition with a composition not shown in Table 1 was prepared, and a -C test piece was prepared by extrusion molding, and the four tensile strength, elongation at break, processability during extrusion molding, and trauma resistance were measured. The properties and abrasion resistance were evaluated.

In the trauma resistance test, as shown in Fig. 1, a steel regular pyramid 2 with an apex angle of 90 degrees was pressed against the cable sheath 1 made of the above resin composition with an outer diameter of 20 mm with a load of 1 kg. vinegar,
When the goople was pulled out at a speed of 50#/min, sheath 1
A case where the sheath 1 was not scraped and did not have any hangnails was marked as ○, and a case where sheath 1 was cut and a hangnail was marked was marked as ×.

In addition, the abrasion resistance test was carried out by first extrusion coating the above resin composition on a conductor with an outer diameter of 0.5 # to produce an electric wire 3 having an insulator with an outer diameter of 1.5 mm, and then As shown in the figure, this electric wire 3 is supported by its both capes, a fan-shaped pressing member 4 is pressed against one side of the electric wire 3 with a load of I kg, and a cylindrical pressing member 4 is pressed against the sacral side on the opposite side of the suppressing member 4. push the metal contact member 5;
t t noru. There is a roughness of 15 between the electric wire 3 and the contact member 5.
The No. 0 abrasion arc 6 is run at a speed of 1,500 mm/minute to wear out the insulator by 1 f.

The abrasion probe is provided with a large number of metal conductive parts 7 approximately 10 m long and spaced at 150 mm intervals.

The detector 8C detects electrical continuity between the conductor of the electric wire 3 and the contact member 5, and detects when the insulator is worn away by the abrasion tape and the conductor is exposed and comes into contact with the abrasion tape 6. Travel distance of wear Arp 6 up to the point (mm)'-
e Abrasion resistance was evaluated using the method. Therefore, the longer the mileage, the higher the wear resistance.

These results are also shown in Table 1.

As is clear from the results in Table 1, the resin composition of the present invention has excellent trauma resistance and abrasion resistance, as well as good extrusion processability.

〔Effect of the invention〕

As explained above, the flame retardant resin composition (3) of the present invention
1. (a) 40 to 98 parts by weight of polyolefin resin;
(1)) Thermoplastic with one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride added to the molecule] - Mixture consisting of 2 to 60 bow parts of the lastomer 100@i; part i In contrast, inorganic compound powder is 1.~20
Since the composition contains a large amount of inorganic compound powder, the composition itself has a high cohesive force, becomes hard, and has good trauma resistance and abrasion resistance. [It has effects such as good properties, and is suitable for insulators and sheaths for electric wires, cables, etc.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the external trauma resistance test method in the example, and FIG. 2 is an explanatory diagram showing the six methods of abrasion resistance test.

Claims (1)

Scope of Claims: (a) 40 to 98 parts by weight of a polyolefin resin; (b) A thermoplastic elastomer containing one or more of maleic acid, maleic anhydride, phthalic acid, and phthalic anhydride added to the molecule. Mixture 10 consisting of 2 to 60 parts by weight
A resin composition comprising 1 to 200 parts by weight of an inorganic compound powder per 0 parts by weight.