JPH10310712A - Rubber-plastic composition and electric wire and cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of realizing a molded product and an electric wire and cable excellent in water resistance by including a rubber or a plastic and an inorganic filler having the surface treated with a specific fluorine-based polymer therein. SOLUTION: This composition is obtained by including (A) a rubber or a plastic (e.g. a blend of 50-100 wt.% fluorine-based elastomer copolymer with 0-50 wt.% fluororesin) and (B) an inorganic filler (e.g. calcium carbonate) having the surface treated with a fluorine based polymer, having fluoroalkyl groups at both ends or the fluoroalkyl group at one terminal and containing at least one of carboxyl group, sulfone group, silanol group and hydroxy group in the structural formula thereof [e.g. a compound represented by formula I (RF is any of formulas II to IV)]. The component B is compounded in an amount of preferably 5-200 pts.wt. based on 100 pts.wt. component A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber / plastic composition and an electric wire / cable having a coating layer formed on the outer periphery of a conductor or an electric wire core using the composition. In particular, the present invention provides a rubber / plastic composition capable of realizing a molded article and an electric wire / cable excellent in water resistance.

[0002]

2. Description of the Related Art Various rubber materials and plastic materials are used as insulation coating materials for electric wires and cables.
Rubber materials include natural rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, styrene butadiene rubber, ethylene propylene diene rubber, silicone rubber, and the like.The plastic material is polyethylene,
Examples include polypropylene, polyvinyl chloride, and polyamide.

[0003] When an inorganic filler is mixed with these rubbers and plastics, the water resistance tends to be remarkably reduced. Further, if a large amount of the inorganic filler is mixed, the dispersibility of the inorganic filler is deteriorated, and the mechanical properties are significantly reduced.

[0004]

In order to improve water resistance and mechanical properties, it has been proposed to treat the surface of an inorganic filler with vinyl silane or the like. Is easy to hydrolyze and shows good water resistance and mechanical properties at the beginning of use,
As time goes by, the original performance will not be exhibited.

On the other hand, fluoroelastomer-based copolymers are excellent in flexibility, heat stability, heat aging resistance, electrical insulation, oil resistance, chemical resistance, flame retardancy, and the like. It has been used as an insulating coating material for cables. Also,
Fluorine-containing elastomeric copolymers have excellent heat resistance,
It is used for various applications such as gaskets, packings, diaphragms, hoses, etc., making use of oil resistance and chemical resistance.

The fluorine-containing elastomeric copolymer is expensive in itself, so it is economically advantageous to use a large amount of filler as far as the properties are not adversely affected. When a large amount of the agent is blended, the filler is difficult to be uniformly dispersed in the fluoroelastomer-based copolymer, and there is a problem that the mechanical properties of the molded article are significantly reduced.

Further, in the fields of electric equipment, automobiles, aircrafts, ships and the like in which the fluoroelastomer-based copolymer-coated electric wires / cables are used, excellent anti-heat softening properties, that is, high cut-through resistance are strongly required. When a large amount of filler is added to improve cut-through resistance, mechanical properties are reduced, and a problem that a dielectric breakdown voltage is significantly reduced is newly pointed out. It became so.

The present invention has been made in view of such a point, and an object of the present invention is to solve the above-mentioned disadvantages of the prior art and to provide a rubber / plastic composition containing a filler having excellent water resistance. Molded articles and electric wires and cables.

[0009]

The rubber / plastic composition of the present invention comprises a rubber or plastic and an inorganic filler, and the inorganic filler has a fluoroalkyl group at both ends or one end. It is characterized by being surface-treated with a system polymer.

Further, the electric wire / cable according to the present invention is the electric wire / cable in which a coating layer made of a rubber / plastic composition containing rubber or plastic and an inorganic filler is formed on the outer periphery of a conductor or an electric wire core. The inorganic filler is one that is surface-treated with a fluoropolymer having a fluoroalkyl group at both terminals or one terminal.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, rubbers and plastics are not particularly specified, but include all. Examples of the rubber material include natural rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, styrene butadiene rubber, butadiene acrylonitrile copolymer, ethylene propylene diene rubber, butyl rubber,
Polyisoprene, silicone rubber, fluorine rubber, fluorine-containing elastomer copolymer (vinylidene fluoride-hexafluoropropene copolymer, vinylidene fluoride-hexafluoropropene-tetrafluoroethylene copolymer, vinylidene fluoride-pentafluoro Propene copolymer,
Vinylidene fluoride-chlorotrifluoroethylene-based copolymer, tetrafluoroethylene-propylene-based copolymer, tetrafluoroethylene-propylene-vinylidene fluoride-based copolymer, etc.). As plastic materials, polyethylene, polypropylene, ethylene-α-olefin copolymer, ethylene-vinyl acetate-vinyl chloride copolymer, ethylene-vinyl chloride copolymer, polyvinyl acetate, ethylene-vinyl acetate copolymer,
Ethylene-octene copolymer, polyvinyl chloride, chlorinated polyethylene, chlorinated polyethylene-acrylonitrile-styrene copolymer, chlorinated polyether, polyvinylidene chloride, modified polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene , Perfluoroalkoxy fluororesin, tetrafluoroethylene-hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, polychlorotrifluoroethylene, vinylidene fluoride-hexafluoropropene copolymer, 1-dihydroperfluoropropene Copolymer, tetrafluoroethylene-perfluoroalkylvinyl ether copolymer, ethylene-chlorotrifluoroethylene copolymer, polyvinyl fluoride, polyurethane, polyamide, polyamide Doimide, polyamide elastomer, polycarbonate, modified polycarbonate, polyether sulfone, polyphenylene sulfide, polyphenylene sulfone, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polysulfone, acrylate-styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, Methacrylate-butylene-styrene copolymer, methacryl-styrene copolymer, styrene-acrylonitrile copolymer, oxybenzoyl polyester, phenolic resin, polyacetal, methacrylic resin, epoxy resin, unsaturated polyester resin, silicone resin, and the like, These may be denatured ones, and may be used in combination as necessary. It is also possible.

In particular, when a fluorine-containing elastomer is used, it is preferable to blend a fluorine-containing resin with the fluorine-containing elastomer-based copolymer. Considering the mechanical strength and flexibility of the obtained molded article, the fluorine-containing elastomer is preferred. It is preferable to blend 50 to 100% by weight of the copolymer and 0 to 50% by weight of the fluororesin.

In the present invention, as the inorganic filler, general fillers such as clay, talc, calcium carbonate, hydrotalcite, channel black, furnace black (SAF, HAF, FEF, SRF, GP
E, ECF, etc.), oxides, hydroxides, carbonates, sulfides, nitrates, chlorides such as carbur blacks represented by thermal blacks (FT, MT, acetylene black, etc.), magnesium, aluminum, calcium, etc. And the like. Calcium carbonate is most preferred in that it has good thermal stability and, even when blended in large amounts, does not significantly reduce heat aging characteristics. When the particle size of the inorganic filler is too large, the dielectric breakdown voltage tends to decrease, and when it is too small, the heat resistance tends to decrease. Therefore, it is preferable to use one having a particle size of 4 μm or less, particularly 0.7 to 1.5 μm. .

The inorganic filler is rubber / plastic 100
It is preferable to mix 5 to 200 parts by weight with respect to parts by weight.
It is preferable to add 120 parts by weight. If the amount is less than 20 parts by weight, it is difficult to obtain the effect of improving the performance, and if it is more than 120 parts by weight, the mechanical properties tend to deteriorate.

In the present invention, by blending an inorganic filler surface-treated with a specific fluoropolymer into a rubber or plastic, the inorganic filler is easily dispersed uniformly in the rubber or plastic, and a large amount of the inorganic filler is blended. Even so, a decrease in mechanical properties can be suppressed. That is, when an untreated inorganic filler is blended in rubber / plastic,
Secondary aggregates of 30 μm or more were formed, causing a decrease in mechanical properties. However, when an inorganic filler surface-treated with a fluoropolymer was blended, the filler became 5%.
It was confirmed that the particles were micro-dispersed to a particle size of not more than μm, thereby suppressing a decrease in mechanical properties.

It has also been confirmed that a reduction in water resistance can be suppressed by adding an inorganic filler surface-treated with a specific fluoropolymer to rubber / plastic.
When blended with rubber or plastic having low water resistance, the water resistance can be improved.

In the present invention, the fluoropolymer for surface-treating an inorganic filler has a fluoroalkyl group at both ends or one end and has a carboxyl group, a sulfone group, a silanol group, a hydroxy group in its structural formula. And at least one of the following groups.
To (8).

[0018]

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[0019]

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[0020]

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[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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The RF in Chemical Formulas 1 to 8 is any of the following Chemical Formulas 9 to 12.

[0027]

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[0028]

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[0029]

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[0030]

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The method for treating the surface of the inorganic filler with a fluoropolymer is not particularly limited, and for example, a wet blending slurry method, a dry blending Henschel mixer method, or the like can be used.

In the present invention, in addition to the inorganic filler, a crosslinking agent, a crosslinking aid, an antioxidant, a lubricant, a processing aid, a stabilizer,
Pigments, surface treatment agents, and the like can be appropriately compounded as needed as needed. When a crosslinking agent or a crosslinking aid is blended, crosslinking can be performed by heat crosslinking, ionizing radiation irradiation crosslinking, or the like. In addition, it may be non-crosslinked.

[0033]

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

<Example 1> 10 parts of an ethylene-propylene-diene copolymer (EP-1 manufactured by Nippon Synthetic Rubber Co., Ltd.)
0 parts by weight, 2 parts by weight of dicumyl peroxide as a crosslinking agent,
0.2 parts by weight of an antioxidant Irganox 1010 (trade name of Ciba Geigy), 1 part by weight of stearic acid as a lubricant, and a surface treatment by a dry blending method with a compound of formula 3 (RF is formula 10) as an inorganic filler. 80 parts by weight of the obtained calcium carbonate A having an average particle size of 1.0 μm were weighed, and each was charged into a small mixer having a capacity of 60 ml and kneaded at 120 ° C. to obtain a compound.

The above compound was pressure-crosslinked at 100 atm for 10 minutes using a press maintained at 180 ° C. to produce a crosslinked sheet having a thickness of 1 mm (10 cm × 10 cm).

Example 2 As an inorganic filler, an average particle diameter of 0.8 μm, which was surface-treated with a compound of formula 1 (RF is formula 9)
A crosslinked sheet was prepared in the same manner as in Example 1 except that 60 parts by weight of MISTRON Vapor Talc A was used.

Example 3 As an inorganic filler, an average particle diameter of 0.8 μm which was surface-treated with a compound of the formula (6) (RF is a chemical formula (12))
A crosslinked sheet was produced in the same manner as in Example 1 except that 60 parts by weight of the calcined clay of m was used.

<Example 4> In the same manner as in Example 1 except that an ethylene-vinyl acetate copolymer (manufactured by Mitsubishi Chemical Corporation, X-501) was used instead of the ethylene-propylene-diene copolymer. A crosslinked sheet was produced.

Example 5 An average particle diameter of 0.8 μm which was surface-treated with a compound of formula 1 (RF is formula 9) as an inorganic filler
A crosslinked sheet was produced in the same manner as in Example 4 except that 60 parts by weight of MISTRON Vapor Tack A was used.

Example 6 A crosslinked sheet was prepared in the same manner as in Example 1 except that low-density polyethylene (Jakeless LDW3000, manufactured by Nippon Polyolefin Co., Ltd.) was used instead of the ethylene-propylene-diene copolymer. did.

Example 7 As an inorganic filler, an average particle diameter of 0.8 μm which was surface-treated with a compound of formula 6 (RF is formula 12)
A crosslinked sheet was produced in the same manner as in Example 6, except that 60 parts by weight of the calcined clay of m was used.

Example 8 Chlorinated polyethylene (Eraslen 401A, manufactured by Showa Denko KK) was used in place of the ethylene-propylene-diene copolymer, and 5 parts by weight of tribasic lead sulfate was used as a stabilizer. A crosslinked sheet was produced in the same manner as in Example 1 except for the above.

Example 9 As an inorganic filler, an average particle diameter of 0.8 μm, which was surface-treated with a compound of formula 1 (RF is formula 9)
A crosslinked sheet was prepared in the same manner as in Example 8, except that 60 parts by weight of MISTRON Vapor Tack A was used.

Comparative Example 1 A crosslinked sheet was prepared in the same manner as in Example 1 except that 60 parts by weight of untreated calcium carbonate B having an average particle size of 1.0 μm was used as an inorganic filler.

Comparative Example 2 A crosslinked sheet was prepared in the same manner as in Example 4, except that 60 parts by weight of untreated calcium carbonate B having an average particle size of 1.0 μm was used as an inorganic filler.

<Comparative Example 3> As an inorganic filler, untreated Mythrone vapor talc B having an average particle size of 0.8 µm was used.
A crosslinked sheet was prepared in the same manner as in Example 6, except that 0 parts by weight was used.

Table 1 shows the compositions of Examples 1 to 9 and Comparative Examples 1 to 3. Table 1 also shows the evaluation results of the inorganic filler dispersibility and the water resistance of the crosslinked sheets of the above examples.

The dispersibility of the inorganic filler was determined by cutting the crosslinked sheet with a microtome and observing the cross section with a scanning electron microscope. △ × 10 μm or more ×
Was determined.

The water resistance was measured by measuring the water absorption (wt%) after immersion in warm water at 50 ° C. for 60 days, and showed the value.

[0050]

[Table 1]

Example 10 Vinylidene fluoride-propylene hexafluoride copolymer (Mouni viscosity ML _{1 + 10} (100
C): 50 parts by weight, 20 parts by weight of an ethylene-tetrafluoroethylene-chlorotrifluoroethylene copolymer (melting point: 225 ° C, melt index: 30), and 1 part by weight of a cross-linking aid, triallyl isocyanurate. Parts, 1 part by weight of barium stearate as a lubricant, and 70 parts by weight of calcium carbonate C having an average particle diameter of 1.0 μm and surface-treated by a dry blend method with a compound of formula 1 (RF is formula 9) as an inorganic filler. These were charged into a kneader having a capacity of 3 liters, and kneaded at 250 ° C. to obtain a fluorine-containing elastomer compound.

This fluorine-containing elastomer compound is
Head temperature 300 ° C, first cylinder temperature 250
° C, L / D with the second cylinder temperature set to 280 ° C
= 22, extruded and coated to a thickness of 0.4 mm on the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² , and then irradiated with an electron beam of 10 Mrad to perform crosslinking. A fluoroelastomer-coated electric wire was manufactured.

Example 11 Vinylidene fluoride-propylene hexafluoride copolymer (Mouni viscosity ML _{1 + 10} (100
C): 100 parts by weight of 50), 1 part by weight of triallyl isocyanurate as a crosslinking aid, 1 part by weight of barium stearate as a lubricant, and dry blending with a compound of formula 6 (RF is formula 9) as an inorganic filler. Average particle size surface-treated by
100 parts by weight of 0 μm calcium carbonate D were weighed, and these were charged into a kneader having a capacity of 3 liters.
The mixture was kneaded at 0 ° C. to obtain a fluorine-containing elastomer compound.

This fluorine-containing elastomer compound was extruded onto the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² to a thickness of 0.4 mm and crosslinked in the same manner as in Example 10 to form a fluorine-containing elastomer-coated wire. Was manufactured.

Example 12 Vinylidene fluoride-propylene hexafluoride copolymer (Mouni viscosity ML _{1 + 10} (100
° C): 50), 70 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1
30 parts by weight of a copolymer (melting point: 225 ° C.), 1 part by weight of triallyl isocyanurate as a cross-linking aid, 1 part by weight of barium stearate as a lubricant, and a compound of formula 6 as an inorganic filler (RF is ) 60 parts by weight of calcium carbonate E having an average particle size of 1.5 μm which has been surface-treated by dry blending in step (1) are weighed, put into a kneader having a capacity of 3 liters, and kneaded at 250 ° C. to obtain a fluorine-containing elastomer compound. Was.

This fluorine-containing elastomer compound is extruded and coated on the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² so as to have a thickness of 0.4 mm in the same manner as in Example 10, and is crosslinked to form a fluorine-containing elastomer-coated electric wire. Was manufactured.

Example 13 A tetrafluoroethylene-propylene copolymer (Mooney viscosity ML _{1 + 10} (100
80 ° C.): 100 parts by weight, 20 parts by weight of an ethylene-tetrafluoroethylene-chlorotrifluoroethylene copolymer (melting point: 225 ° C., melt index: 30), and 1 part by weight of a cross-linking aid, triallyl isocyanurate. Parts, 1 part by weight of barium stearate as a lubricant, and 80 parts of talc having an average particle diameter of 0.8 μm, which was surface-treated with a compound of formula 2 (RF is formula 10) as an inorganic filler by dry blending.
Each part by weight was weighed, put into a kneader having a capacity of 3 liters, and kneaded at 250 ° C. to obtain a fluorine-containing elastomer compound.

This fluorine-containing elastomer compound was extruded onto the outer periphery of a copper stranded wire having a sectional area of 75 mm ² so as to have a thickness of 0.4 mm and crosslinked in the same manner as in Example 10 to form a fluorine-containing elastomer-coated wire. Was manufactured.

Example 14 Tetrafluoroethylene-propylene copolymer (Mooney viscosity ML _{1 + 10} (100
100 ° C.): 100 parts by weight, 1 part by weight of triallyl isocyanurate as a cross-linking aid, 1 part by weight of barium stearate as a lubricant, and a compound of formula (RF) as an inorganic filler.
100 parts by weight of calcined clay having an average particle size of 0.8 μm, surface-treated by dry blending method in Chemical formula 11), were weighed, placed in a kneader having a capacity of 3 liters, and kneaded at 250 ° C. to obtain a fluorine-containing elastomer compound. Was.

This fluorine-containing elastomer compound was extruded onto the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² so as to have a thickness of 0.4 mm and crosslinked in the same manner as in Example 10 to form a fluorine-containing elastomer-coated electric wire. Was manufactured.

Example 15 Vinylidene fluoride-propylene hexafluoride copolymer (Mouni viscosity ML _{1 + 10} (10
C): 50), 100 parts by weight, 2 parts by weight of dicumyl peroxide as a crosslinking agent, 1 part by weight of triallyl isocyanurate as a crosslinking aid, 1 part by weight of barium stearate as a lubricant, and carbonic acid as an inorganic filler. 100 parts by weight of calcium D were weighed, and each was charged into a kneader having a capacity of 3 liters, and kneaded at 150 ° C. to obtain a fluorine-containing elastomer compound.

This fluorine-containing elastomer compound was prepared by setting the head temperature to 100 ° C., the first cylinder temperature to 80 ° C., and the second cylinder temperature to 100 ° C. L / D = 22
Into a 40 mm extruder, and extruded and coated on the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² so as to have a thickness of 0.4 mm,
Then, it was exposed to a high-temperature steam pipe having a steam pressure of 18 atm for 1 minute to crosslink, thereby producing a fluorine-containing elastomer-coated electric wire.

Comparative Example 4 A copolymer of vinylidene fluoride and propylene hexafluoride (Mouni viscosity ML _{1 + 10} (100
C): 50), 100 parts by weight, 1 part by weight of triallyl isocyanurate as a cross-linking aid, 1 part by weight of barium stearate as a lubricant, carbonic acid having an average particle size of 1.0 μm, which was surface-treated with calcium stearate as an inorganic filler. Calcium F
Was weighed, and these were charged into a 3 liter kneader and kneaded at 250 ° C. to obtain a fluorine-containing elastomer compound.

This fluorine-containing elastomer compound was extruded and coated on the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² so as to have a thickness of 0.4 mm in the same manner as in Example 10, and then crosslinked to form a fluorine-containing elastomer-coated electric wire. Was manufactured.

Comparative Example 5 A vinylidene fluoride-propylene hexafluoride copolymer (Mouni viscosity ML _{1 + 10} (100
° C): 50), 70 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1
30 parts by weight of a copolymer (melting point: 225 ° C.), 1 part by weight of triallyl isocyanurate as a cross-linking aid, 1 part by weight of barium stearate as a lubricant, and an average particle diameter of 1 treated with aminosilane as an inorganic filler. 0.5 μm of calcium carbonate G (50 parts by weight) was weighed, and each was charged into a 3-liter kneader and kneaded at 250 ° C. to obtain a fluorine-containing elastomer compound.

This fluoroelastomer compound was extruded onto the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² so as to have a thickness of 0.4 mm and crosslinked in the same manner as in Example 10 to form a fluoroelastomer-coated wire. Was manufactured.

Comparative Example 6 Tetrafluoroethylene-propylene copolymer (Mooney viscosity ML _{1 + 10} (100 ° C.):
100), 30 parts by weight of an ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 copolymer (melting point: 225 ° C.), 1 part by weight of a cross-linking aid, triallyl isocyanurate, 1 part by weight of barium stearate as a lubricant, and an average particle diameter of 1 as an inorganic filler.
80 parts by weight of 9 μm calcium carbonate H were weighed, and these were charged into a kneader having a capacity of 3 liters.
The mixture was kneaded at 0 ° C. to obtain a fluorine-containing elastomer compound.

This fluoroelastomer compound was extruded onto the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ^{2 in} a thickness of 0.4 mm and crosslinked in the same manner as in Example 10 to form a fluoroelastomer-coated electric wire. Was manufactured.

Comparative Example 7 Tetrafluoroethylene-propylene copolymer (Mooney viscosity ML _{1 + 10} (100 ° C.):
100), 50 parts by weight of an ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 copolymer (melting point: 225 ° C.), 1 part by weight of a cross-linking aid, triallyl isocyanurate, 1 part by weight of barium stearate as a lubricant and 150 parts by weight of an untreated clay having an average particle diameter of 0.8 μm as an inorganic filler were weighed, and these were charged into a kneader having a capacity of 3 liters.
The mixture was kneaded at 0 ° C. to obtain a fluorine-containing elastomer compound.

This fluorine-containing elastomer compound was extruded onto the outer periphery of a copper stranded wire having a cross-sectional area of 75 mm ² so as to have a thickness of 0.4 mm and crosslinked in the same manner as in Example 10 to form a fluorine-containing elastomer-coated electric wire. Was manufactured.

Table 2 shows Examples 10 to 15 and Comparative Examples 4 to
7 is a summary of the formulation.

[0072]

[Table 2]

Table 3 shows the evaluation results of the fluorine-containing elastomer-coated electric wires of the respective examples. The characteristic test was performed for the following four items.

Insulation breakdown voltage: A fluorine-containing elastomer-coated electric wire is cut into a length of 70 cm, the coating layers at both ends are peeled off, and both ends are joined. This was immersed in water, a voltage of 1.5 kV was applied between the test sample and water for 1 minute, and then the voltage was increased at a rate of 1 kV / min to obtain a dielectric breakdown voltage of the test sample.

Dispersibility of inorganic filler: A part of the covering of the fluorine-containing elastomer-coated electric wire was cut out, cut into a very thin section with a microtome, and the cross section was observed with a scanning electron microscope to determine the size of the aggregate of the inorganic filler. ○ 5 μm or less
A sample having a size of 10 μm to 10 μm was determined to be x, and a sample having a size of 10 μm or more was determined to be x.

Tensile properties: A tube obtained by extracting a copper stranded wire from a fluorine-containing elastomer-coated electric wire was subjected to a tensile test according to JISC3005.

Cut-through resistance: A fluorine-containing elastomer-coated electric wire is placed on a 90 ° edge, a predetermined load is applied to the electric wire, the wire is preheated at 200 ° C. for 5 minutes, then held for 10 minutes, and the load at the time of conduction is determined. Was.

[0078]

[Table 3]

As can be seen from Table 3, the fluorine-containing elastomer-coated electric wire of Comparative Example 4 has good cut-through resistance, but has a low dielectric breakdown voltage and poor mechanical properties due to poor dispersibility of the inorganic filler. bad. The fluorine-containing elastomer-coated electric wire of Comparative Example 5 also has a poor cut-through property and a poor dispersibility of the inorganic filler, so that the dielectric breakdown voltage is low and the mechanical properties are poor. The fluorine-containing elastomer-coated electric wire of Comparative Example 6 has a good cut-through property, but has a low dielectric breakdown voltage and poor mechanical properties due to poor dispersibility of the inorganic filler. The fluorine-containing elastomer-coated wire of Comparative Example 7 has good cut-through properties, but has a low dielectric breakdown voltage.

On the other hand, Examples 10 to 15 of the present invention
All of the above-mentioned fluorine-containing elastomer-coated electric wires had good dispersibility of the inorganic filler, and as a result, showed excellent results with a dielectric breakdown voltage of 20 kV or more, and also had good cut-through properties of 500 g or more. In addition, the fluorine-containing elastomer-coated wire of the present invention does not show any test results, of course, but the inherent flexibility of the fluorine-containing elastomer itself, heat stability, heat aging resistance, electrical insulation, oil resistance, chemical resistance, It also has flame retardancy.

[0081]

The molded article made of the rubber / plastic composition of the present invention incorporates an inorganic filler treated with a specific fluoropolymer, and can realize a molded article excellent in water resistance and mechanical properties. . Further, when a specific fluororesin polymer is mixed with the fluoroelastomer composition, it has a high dielectric breakdown voltage value in addition to water resistance and mechanical properties, and also has good cut-through properties. In addition, it has excellent flexibility, thermal stability, heat aging resistance, electrical insulation, oil resistance, chemical resistance, flame retardancy, etc., as well as insulation materials and sheath materials for electric wires and cables, as well as sealing materials. It is industrially very useful, applicable to packings, gaskets, O-rings, rollers, roll covers, shaft seals, tubes, hoses and the like.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Watanabe 5-1-1, Hidaka-cho, Hitachi City, Ibaraki Prefecture Power Systems Research Laboratory, Hitachi Cable, Ltd. (72) Inventor Yoshihisa Kato 5 Hidaka-cho, Hitachi City, Ibaraki Prefecture 1-1-1 Hitachi Power Systems Co., Ltd. Power Systems Research Laboratories (72) Inventor Kenji Asano 5-1-1 Hidaka-cho, Hitachi City, Ibaraki Pref. Hitachi Power Systems Co., Ltd. Power Systems Research Labs (72) Inventor Hideki Yagyu Ibaraki Prefecture 5-1-1 Hidaka-cho, Hitachi City Hitachi Power Systems Co., Ltd. Power System Research Laboratories (72) Inventor Hideo Sawada 572-7 Yao, Taharahoncho, Isogi-gun, Nara Prefecture

Claims (8)

[Claims] 1. An inorganic filler comprising rubber or plastic and an inorganic filler, wherein the inorganic filler is surface-treated with a fluoropolymer having a fluoroalkyl group at both terminals or one terminal. Rubber and plastic composition. 2. The fluoropolymer has a fluoroalkyl group at both terminals or one terminal and has at least one of a carboxyl group, a sulfone group, a silanol group, and a hydroxy group in its structural formula. The rubber / plastic composition according to claim 1. 3. The rubber / plastic composition according to claim 1, wherein said rubber or plastic is a fluorine-containing elastomer. 4. The fluoroelastomer comprises 50 to 100% by weight of a fluoroelastomer-based copolymer and 0 to 50% by weight of a fluororesin.
The fluoroelastomer composition according to claim 3, which is a blend with 50% by weight. 5. An electric wire or cable in which a coating layer made of a rubber / plastic composition containing rubber or plastic and an inorganic filler is formed on the outer periphery of a conductor or an electric wire core, wherein the inorganic filler is at both ends or pieces. An electric wire or cable which has been surface-treated with a fluoropolymer having a fluoroalkyl group at a terminal. 6. The fluoropolymer has a fluoroalkyl group at both ends or one end, and contains at least one of a carboxyl group, a sulfone group, a silanol group, and a hydroxy group in its structural formula. An electric wire or cable according to claim 5. 7. An electric wire or cable according to claim 5, wherein said rubber or plastic is a fluorine-containing elastomer. 8. The fluoroelastomer comprises 50 to 100% by weight of a fluoroelastomer-based copolymer and 0 to 50% by weight of a fluororesin.
The electric wire / cable according to claim 7, which is a blend with 50% by weight.