JP2002338765A - Cross-linkable resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cabtyre cable which is covered with a covering material having characteristics, such as low-temperature softness and resistances to abrasion, flexing, and creep, equal to those of a cross-linked rubber composition and which can be produced at a low cost; and a resin composition used as the covering material meeting the above requirements. SOLUTION: An ionically cross-linkable polyvinyl chloride of 100 pts.wt., consisting of a copolymer of vinyl chloride and a free-radical-polymerizable unsaturated carboxylic acid having a free carboxy group and an ionic cross- linking agent, is compounded with 5-80 pts.wt. filler and 30-120 pts.wt. plasticizer, thus giving an ionically cross-linkable resin composition which meets the above requirements.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cabtire cable, particularly a cabtire cable for construction work temporary wiring and a crane having excellent bending resistance, abrasion resistance, creep resistance, etc., and its sheath and the like. The present invention relates to a crosslinkable resin composition constituting the material.

[0002]

2. Description of the Related Art Conventionally, a covering material such as an insulator or a sheath of a cabtire cable used for temporary wiring of construction work is a crosslinked rubber composition obtained by crosslinking (vulcanizing) rubber such as synthetic rubber and natural rubber. It is composed of this is,
This is because the crosslinked rubber composition has excellent wear resistance, flex life characteristics, creep resistance, low-temperature flexibility and the like, and can withstand extremely severe use conditions such as temporary wiring for construction work.

[0003] However, the crosslinked rubber composition has a disadvantage that the production cost is high because a crosslinking step with sulfur or an organic peroxide is required. Therefore, it is conceivable to use an inexpensive plasticized polyvinyl chloride composition as a covering material for this type of cabtire cable.

However, in a cabtire cable having a coating made of the plasticized polyvinyl chloride composition, the coating has a wear resistance, a bending resistance, a heat resistance, a creep resistance, etc., of a coating made of a crosslinked rubber composition. Significantly lower than the material,
There is a drawback that cannot withstand severe use. The reason for this is that the plasticized polyvinyl chloride composition is non-crosslinked, has low cohesive strength of the composition itself, and has little resistance to various external forces.

[0005]

Accordingly, an object of the present invention is to provide a coating material comprising a crosslinked rubber composition having properties such as abrasion resistance, flex resistance, creep resistance and low temperature flexibility, and An object of the present invention is to provide a cabtire cable which can be manufactured at a low cost and a resin composition forming a covering material for the cable.

[0006]

The object of the present invention is to provide an ion-crosslinkable polyvinyl chloride comprising 100 parts by weight of a copolymer of vinyl chloride and a radically polymerizable unsaturated carboxylic acid having a free carboxyl group and an ion-crosslinking agent. The problem can be solved by forming a covering material such as an insulator or a sheath of a cabtire cable with a crosslinkable resin composition containing 5 to 80 parts by weight of a filler and 30 to 120 parts by weight of a plasticizer.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
First, the ion-crosslinkable polyvinyl chloride as the base polymer of the crosslinkable resin composition of the present invention will be described. The ion-crosslinkable polyvinyl chloride is a copolymer obtained by copolymerizing a vinyl chloride monomer and a radically polymerizable unsaturated carboxylic acid having one free carboxyl group, and reacting with the copolymer to form an ion. Consisting of a crosslinking agent that crosslinks
It is a vinyl chloride polymer having ionic crosslinkability.

[0008] The radically polymerizable unsaturated carboxylic acid having a free carboxyl group, which constitutes the above copolymer, is a radically polymerizable unsaturated carboxylic acid having at least one free carboxyl group per molecule and having 3 to 8 carbon atoms. Acid is used,
Specifically, for example, unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, and cinnamic acid; maleic acid, itaconic acid, fumaric acid, citraconic acid, unsaturated dicarboxylic acids such as chloromaleic acid, and acids thereof. Anhydrides,
One or more monomers of unsaturated dicarboxylic acid monoesters such as monoalkyl maleate, monoalkyl fumarate and monoalkyl itaconate and derivatives thereof are used. Among these monomers, monoesters of unsaturated dicarboxylic acids such as monomethyl maleate, monobutyl maleate and monomethyl fumarate are particularly preferred.

The copolymerization of a vinyl chloride monomer and a radically polymerizable unsaturated carboxylic acid is carried out by radical polymerization using a conventional radical polymerization initiator, and a suspension polymerization method,
An emulsion polymerization method or the like can be employed. In addition to the above two monomers, other monomers such as ethylene, propylene, vinyl acetate, vinyl ether, acrylate, methacrylate, and styrene may be copolymerized in the copolymer.

The amount of the radically polymerizable unsaturated carboxylic acid in the copolymer is 0.2 to 30% by weight,
The amount of vinyl chloride is 70 to 99.8 wt%,
When another monomer is copolymerized, the amount of the monomer is set to 0 to 20% by weight. If the amount of the radically polymerizable unsaturated carboxylic acid is less than 0.2 wt%, improvement in creep properties at high temperatures cannot be obtained, and if it exceeds 30 wt%, the properties as polyvinyl chloride are impaired and a copolymer is obtained. Is difficult to manufacture.

As the ionic crosslinking agent, a monovalent or divalent metal ion compound is used, and Li, Na, K, C
oxides, hydroxides, acetates, propionates, octylates, caprates, stearates, naphthenates and other carboxylates of metals such as s, Mg, Ca, Ba, Zn, etc., thiocarboxylic acids Salts, sulfonates, phosphates and complex salts of the above metals with acetylacetone and the like are used. These may be used alone or in combination of two or more. As the ionic cross-linking agent, a water-insoluble one is preferable because it has low hygroscopicity and can prevent foaming in a subsequent step.

In this ionically crosslinkable polyvinyl chloride, the ionically crosslinkable agent ionically bonds to the free carboxyl group in the copolymer, thereby ionically crosslinking the copolymer.
This ionic cross-link takes a three-dimensional cross-link structure at normal temperature,
At a high temperature of 120 ° C. or higher, ionic bonds are dissociated and crosslinking is eliminated, and ionic crosslinkable polyvinyl chloride behaves as a thermoplastic polymer.

The amount of the ionic cross-linking agent to be added is 0.1 to 3 times the molar equivalent of the amount of free carboxyl groups in the copolymer. Even if the molar equivalent exceeds 3 times, ionic crosslinking does not proceed any further.

The reaction between the copolymer and the ionic crosslinking agent is as follows:
It is possible by mixing and kneading both,
After blending a plasticizer and a filler, which will be described later, they may be reacted by collectively kneading them.

The filler used in the present invention includes calcium carbonate, talc, clay, antimony compounds, metal hydrates, zinc borate, zirconium compounds, phosphorus compounds, bromine compounds, silica, wollastonite, One or a mixture of two or more of zeolites, metal oxides and the like, and those obtained by subjecting them to a surface treatment are used.

Among these fillers, antimony compounds, metal hydrates, zinc borate, zirconium compounds,
Phosphorus compounds, bromine-based compounds, silica, etc. also serve as a flame retardant at the same time, and provide the mechanical properties required for the crosslinkable resin composition, such as trauma resistance, abrasion resistance, creep resistance, and flame retardancy. Things.

The amount of the filler is from 5 to 80 parts by weight, preferably from 10 to 60 parts by weight, based on 100 parts by weight of the ion-crosslinkable polyvinyl chloride. If it exceeds 80 parts by weight, the physical properties are greatly reduced.

As the plasticizer used in the present invention, those used for ordinary polyvinyl chloride can be used, and phthalic acid derivatives, isophthalic acid derivatives, tetrahydrophthalic acid derivatives, adipic acid derivatives, azelaic acid derivatives, Sebacic acid derivative, dodecane-2-acid derivative, maleic acid derivative, fumaric acid derivative, trimellitic acid derivative, pyromellitic acid derivative, citric acid derivative, itaconic acid derivative, oleic acid derivative, ricinoleic acid derivative, stearic acid derivative, phosphorus An acid derivative, a glutaric acid derivative, a paraffin derivative, a glycerin derivative, an epoxy derivative, a polymerizable plasticizer, or the like is used alone or in combination of two or more.

More specifically, phthalic acid esters such as di-2-ethylhexyl phthalate, di-n-octyl phthalate, diisodecyl phthalate, dibutyl phthalate and dihexyl phthalate, dioctyl adipate,
Linear dibasic acid esters such as dioctyl sebacate, trimellitic acid esters, polyester polymer plasticizers, epoxy plasticizers such as epoxidized soybean oil, epoxidized linseed oil, and phosphorus such as triphenyl phosphate and tricresyl phosphate One or a mixture of two or more such as an acid ester-based plasticizer is used.

The amount of the plasticizer is 30 to 120 parts by weight based on 100 parts by weight of the ion-crosslinkable polyvinyl chloride.
Preferably it is 40 to 100 parts by weight. The blending amount is 30
If the amount is less than 10 parts by weight, flexibility becomes insufficient and the material becomes a hard material.
If the amount exceeds 0 parts by weight, deformation due to heat increases.

In the crosslinkable resin composition of the present invention, a stabilizer, a lubricant, an antioxidant, an ultraviolet absorber, a processing aid, a colorant, an impact resistance and the like are appropriately compounded in the same manner as in the ordinary polyvinyl chloride composition. can do. Stabilizers are important for ensuring the thermal stability of the above copolymers. Various stabilizers such as metallic soaps, organotins, lead and nonmetals are added to 100% by weight of ion-crosslinkable polyvinyl chloride. 2 to 10 parts
It is desirable to add about parts by weight.

The cabtire cable of the present invention has a covering material comprising the above-mentioned crosslinkable resin composition. Specifically, the cabtire cable covers an insulator extruded on a conductor or an insulated wire core having the insulator. In this case, a sheath or the like is formed from such a crosslinkable resin composition. The thickness of the insulator is 0.3
The sheath has a thickness of 1 to 10 mm.

Further, the cabtire cable of the present invention comprises:
When this cable is subjected to the abrasion test specified in JIS C-3327, the abrasion loss of the insulator or sheath after 400 rotations of the abrasion rotary plate is 1 mm or less. The amount of abrasion is a value indicating that the abrasion resistance of this crosslinkable resin composition is extremely excellent, and exhibits a wear resistance equal to or higher than that of a cabtire cable using a conventional crosslinked rubber composition. It is.

In such a crosslinkable resin composition, since the base polymer is made of ionically crosslinkable polyvinyl chloride,
At room temperature, it is ionically cross-linked, so it has abrasion resistance,
It has excellent bending resistance, creep resistance, heat resistance, and low-temperature flexibility. In addition, since an appropriate amount of a filler and a plasticizer are blended, it has characteristics such as high mechanical strength and sufficient flexibility. For this reason, the cabtire cable of the present invention can be used without being damaged for a long period of time even under extremely severe use conditions such as temporary wiring for construction work and cranes.

The following is a specific example. A composition having a composition (parts by weight) shown in Tables 1 and 2 was kneaded and extruded onto a copper stranded wire having an outer diameter of 2.4 mm to prepare an insulated wire core having an insulator having a thickness of 0.8 mm. . After three insulated wires were twisted, the same composition was extrusion-coated thereon to provide a sheath having a thickness of 1.9 mm, thereby producing a cabtire cable having a finish diameter of 12.4 mm. The cabtire cable was measured for a tensile test, an oil resistance test, a hot set test, a restoration rate, and a wear resistance test, which are described below, according to JIS C3312.

In the tensile test, hot set test and oil resistance test, a material cut out of the sheath was used as a test piece. In the tensile test, those satisfying the specified values of JIS C3312 were accepted. The test conditions for the hot set test were such that a weight having a load of 20 g / mm ² was hung on a test piece at 80 ° C. for 15 minutes, and the elongation between the marked lines was measured. After that, the weight was removed and the plate was left at room temperature for 5 minutes, and then the restoration rate was measured.

In the oil resistance test, the test pieces were immersed in machine oil at 70 ° C. for 4 hours, and those having a residual ratio of tensile strength of 90% or more were evaluated as ○, and those not so were evaluated as Δ. The wear resistance test is
This was performed according to JIS C-3327, and the abrasion amount of the sheath after 400 rotations was measured. The results are shown in Tables 1 and 2.

[0028]

[Table 1]

[0029]

[Table 2]

In Tables 1 and 2, "ion-crosslinkable polyvinyl chloride" refers to a product using a copolymer of vinyl chloride and monomethyl maleate as "plasticized polyvinyl chloride".
A composition obtained by mixing 50 parts by weight of calcium carbonate, 50 parts by weight of diisononyl phthalate, and 5 parts by weight of a lead stabilizer with 100 parts by weight of polyvinyl chloride having an average degree of polymerization of 1100 was used. “DINP” indicates diisononyl phthalate.

[0031]

As described above, the crosslinkable resin composition of the present invention comprises an ionic crosslinkable agent comprising a copolymer of vinyl chloride and a radically polymerizable unsaturated carboxylic acid having a free carboxyl group and an ionic crosslinker. Polyvinyl chloride 100
5 to 80 parts by weight of filler, 30 to plasticizer to parts by weight
120 parts by weight, the ion-crosslinkable polyvinyl chloride is ionically cross-linked at room temperature, so that it has abrasion resistance, flex resistance, creep resistance, heat resistance, and low-temperature flexibility. It will be excellent. In addition, since an appropriate amount of filler and plasticizer are blended, the mechanical strength is high,
Moreover, it has characteristics such as sufficient flexibility.

For this reason, the cabtire cable of the present invention has a very high strength of the insulator and the sheath, and can be used for a long time even under extremely severe use conditions such as a temporary power source for construction work and a crane. Becomes In addition, ionically crosslinkable polyvinyl chloride is
At a high temperature of not less than ° C., the material changes to thermoplasticity, so that it is possible to collect the discarded cabtire cable and reuse the coating material for recycling, which is advantageous in resource saving.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Katsuji Takahara 1440 Rokuzaki, Sakura-shi, Chiba F-term in Fujikura Sakura Works (reference) 4J002 BD051 BD081 BD091 CD162 CF002 CF022 DE056 DE076 DE086 DE096 DE106 DE237 DG036 DH046 DJ007 DJ017 DJ037 DJ047 DK007 EG036 EG046 EG056 EH048 EH148 EW048 FD017 FD028 FD137 FD146 GM00 GT00

Claims (3)

[Claims] 1. An ionic crosslinkable polyvinyl chloride 100 comprising a copolymer of vinyl chloride and a radically polymerizable unsaturated carboxylic acid having a free carboxyl group and an ionic crosslinker.
5 to 80 parts by weight of filler, 30 to plasticizer to parts by weight
A crosslinkable resin composition containing 120 parts by weight. 2. A cabtire cable using the crosslinkable resin composition according to claim 1 as a coating material. 3. The cabtire cable according to claim 2, wherein a wear amount after 400 rotations is 1 mm or less when a wear test specified in JIS C-3327 is performed.