JP2001167635A - Peelable, semi-conductive, water-crosslinkable resin composition for, outer semi-conductive layer of chemically crosslinked polyethylene insulating power cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition for use in an outer semi-conductive layer of a chemically cross-linked polyethylene insulating power cable having an excellent heat resistance and tensile strength, and a water-crosslinked polyethylene insulating power cable manufactured using the same. SOLUTION: Disclosed herein is a chemically cross-linked polyethylene insulating power cable in which an inner semi-conductive layer, a chemically cross- linked polyethylene insulating layer, an outer semi-conductive layer and a jacket layer are formed on a conductor in sequence. In this power cable, the outer semi-conductive layer is formed from a peelable, semi-conductive, water- crosslinkable resin composition, which comprises (a) at least one selected from specific ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers and ethylene-butyl acrylate copolymers, (b) specific polypropylenes (c) specific organopolysiloxane, (d) carbon blacks, (e) unsaturated alkoxysilanes, (f) organic peroxides, and (g) a silanol condensation solvent, the respective components being contained by a specific amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peelable semiconductive resin composition used as an outer semiconductive layer of a chemically crosslinked polyethylene insulated power cable, and a chemically crosslinked polyethylene insulation obtained by coating the composition on a chemically crosslinked polyethylene insulating layer. Regarding power cables.

[0002]

2. Description of the Related Art An ordinary chemically cross-linked polyethylene insulated power cable has a conductor, an inner semiconductive layer,
The outer semiconductive layer is composed of an insulating layer, an outer semiconductive layer, and a jacket layer. In order to prevent other insulation deterioration, the conductive material has a volume specific resistance of about 100 Ω · cm. To make the external semiconductive layer have the above-mentioned volume specific resistance value, and improve the adhesiveness with the chemically cross-linked polyethylene insulating layer, follow external bending or heat cycle, etc., to prevent the occurrence of partial peeling and voids A polymer that is flexible, has good adhesion to chemically cross-linked polyethylene, and does not reduce mechanical strength, elongation, flexibility, and processability despite the filling of a large amount of carbon black is required. As those, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ionomer,
Acid-modified polyethylene and the like have been used. However, when connecting chemically crosslinked polyethylene insulated power cables to each other, the outer semiconductive layer must be peeled off from the chemically crosslinked polyethylene insulated layer to facilitate the terminal treatment work. It must be an external semiconductive layer with good releasability.

[0003] The above-mentioned ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ionomer, acid-modified polyethylene and the like have good adhesiveness, but have poor peelability, heat resistance and high-temperature extrudability. It is enough. Therefore, the peelable semiconductive resin composition used for the outer semiconductive layer of the power cable by the conventional chemical crosslinking method is, for example,
JP-A-58-212007, JP-A-59-23020
5, JP-A-60-189110, JP-A-62-58
No. 518, JP-A-62-117202, JP-A-63-117202
89552, JP-A-3-29210, JP-A-3-2
Many proposals have been made in each of the publications of No. 47641. However, the releasability, heat resistance, high-temperature extrusion processability, etc. are insufficient, the mechanical strength, elongation, cold resistance, etc. are poor, or the external semiconductive layer has releasability and adhesion satisfying all conditions There was no resin composition for use and no power cable made therefrom.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a resin composition which satisfies the following conditions required as an outer semiconductive layer of a power cable in which an insulating layer is composed of chemically crosslinked polyethylene, and a chemically crosslinked polyethylene produced using the same. To provide an insulated power cable. (1) The resin composition for an external semiconductive layer is semiconductive and has a volume specific resistance of 100 Ω · cm or less. (2) When the power cable is bent or subjected to a heat cycle, the elongation percentage is 100% or more in order to maintain flexibility and elongation so as not to cause partial peeling or voids from the chemically crosslinked polyethylene insulating layer. . (3) The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer is smooth and has no fine protrusions. (4) When the outer semiconductive layer is peeled off, the outer semiconductive layer itself does not cut with a weak tensile force.
Pa or more. (5) Cold resistance. (6) When the outer semiconductive layer is peeled off from the chemically cross-linked polyethylene insulating layer, the outer semi-conductive layer is cut with a relatively weak force using a knife, so that the cutting operation can be easily performed without damaging the chemically cross-linked polyethylene layer. , And can be easily peeled off,
The peel strength between the interface with the chemically cross-linked polyethylene insulating layer is 4 kg / 0.5 inch or less so that no residue or scratch remains on the surface of the chemically cross-linked polyethylene layer after peeling. (7) Even if crosslinking with an organic peroxide is not performed, 120
Heat deformation rate at 120 ° C is 40% or less due to heat resistance against heat deformation at 0 ° C.

[0005]

Means for Solving the Problems The present inventors have filed a patent application of Japanese Patent Application No. 11-27261, which the inventor of the present invention has previously invented.
In order to further improve the heat resistance level of the peelable semiconductive resin composition for the outer semiconductive layer of the chemically crosslinked polyethylene insulated power cable disclosed in No. 5, the present invention was completed by applying a water crosslinking technique. Was. That is, the first invention of the present invention relates to a chemically crosslinked polyethylene insulated power cable in which an inner semiconductive layer, a chemically crosslinked polyethylene insulating layer, an outer semiconductive layer and a jacket layer are formed on a conductor from inside to outside. The following (a) used as an external semiconductive layer,
A releasable semiconductive water-crosslinkable resin composition comprising components (b), (c), (d), (e), (f) and (g). (A) (I) an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 50% by weight and a melt mass flow rate of 1.0 to 100.0 g / 10 minutes, and (II) an ethyl acrylate content of 10 to 50% by weight. Ethylene-ethyl acrylate copolymer having a melt mass flow rate of 1.0 to 100.0 g / 10 min, and (III) a butyl acrylate content of 10 to 50% by weight, and a melt mass flow rate of 1.0 to 100.0 g / 10 min. At least one selected from ethylene-butyl acrylate copolymers
00 parts by weight (b) Melt mass flow rate 0.5-30.0 g / 1
0 min, 5 to 50 parts by weight of polypropylene having a density of 0.900 to 0.920 g / cm ³ (c) The following formula (A)

[0006]

Embedded image (Wherein, R ¹ is an aliphatic unsaturated hydrocarbon group, R ² is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group,
0 ≦ x <1, 0.5 <y <3, 1 <x + y <3, 0 <a
≦ 1, 0.5 ≦ b ≦ 3. 0.5 to 50 parts by weight of an organopolysiloxane represented by the formula (d): 7.0 to 350 parts by weight of carbon black (e) 0.5 to 20.0 parts by weight of an unsaturated alkoxysilane (f) Organic peroxide 0 0.05 to 4.0 parts by weight (g) 0.01 to 20.0 parts by weight of a silanol condensation catalyst.

In a second aspect of the present invention, the component of the first aspect further comprises a component (h) having a melt mass flow rate of 0.1 to 30.0 g / 10 minutes and a density of 0.870 to
The following (a), (b), (c), and 0.944 g / cm ³ of a linear ethylene-α-olefin copolymer were added.
It is a peelable semiconductive water-crosslinkable resin composition comprising the components (d), (e), (f), (g) and (h). (A) (I) an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 50% by weight and a melt mass flow rate of 1.0 to 100.0 g / 10 minutes, and (II) an ethyl acrylate content of 10 to 50% by weight. Ethylene-ethyl acrylate copolymer having a melt mass flow rate of 1.0 to 100.0 g / 10 min, and (III) a butyl acrylate content of 10 to 50% by weight, and a melt mass flow rate of 1.0 to 100.0 g / 10 min. At least one selected from ethylene-butyl acrylate copolymers
00 parts by weight (b) Melt mass flow rate 0.5-30.0 g / 1
0 min, 5 to 50 parts by weight of polypropylene having a density of 0.900 to 0.920 g / cm ³ (c) The following formula (A)

[0008]

Embedded image (Wherein, R ¹ is an aliphatic unsaturated hydrocarbon group, R ² is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group,
0 ≦ x <1, 0.5 <y <3, 1 <x + y <3, 0 <a
≦ 1, 0.5 ≦ b ≦ 3. (D) carbon black 7.0 to 350 × (1 + Q / 1)
00) parts by weight (e) unsaturated alkoxysilane 0.5 to 20 × (1 + Q)
/ 100) parts by weight (f) Organic peroxide 0.05 to 4.0 × (1 + Q / 10
0) parts by weight (g) Silanol condensation catalyst 0.01-20 × (1 + Q /
100) parts by weight (h) Melt mass flow rate 0.1 to 30.0 g / 1
0 minutes, 0 to 200 parts by weight of a linear ethylene-α-olefin copolymer having a density of 0.870 to 0.944 g / cm ³ .
(However, Q is the amount (parts by weight) of the component (h).)

The third invention of the present invention is the first invention, wherein the resin composition comprising (a), (b) and (c) and the carbon black component of (d) are heated at 150 to 200 ° C. Heat kneading, and adding the unsaturated alkoxysilane (e),
The organic peroxide of (f) and the silanol condensation catalyst of (g) are blended, and then heated and kneaded at 200 to 250 ° C., and from the inside to the outside on a conductor made by grafting an unsaturated alkoxysilane to a resin component. A releasable semiconductive water-crosslinkable resin composition used as the outer semiconductive layer of a chemically crosslinked polyethylene insulated power cable in which an inner semiconductive layer, a chemically crosslinked polyethylene insulating layer, an outer semiconductive layer and a jacket layer are formed. is there.

A fourth invention of the present invention is the invention according to the second invention, wherein the resin composition comprising (a), (b), (c) and (h) and the carbon black component of (d) are contained in 150 parts. ~
The mixture was heated and kneaded at 200 ° C, and the unsaturated alkoxysilane of (e), the organic peroxide of (f) and the silanol condensation catalyst of (g) were mixed therein, and then heated and kneaded at 200 to 250 ° C to obtain an unsaturated mixture. A chemically cross-linked polyethylene insulated power cable in which an inner semi-conductive layer, a chemically cross-linked polyethylene insulating layer, an outer semi-conductive layer and a jacket layer are formed from inside to outside on a conductor made by grafting an alkoxysilane to a resin component. It is a peelable semiconductive water-crosslinkable resin composition used as an external semiconductive layer. Further, the fifth invention of the present invention provides a resin composition for an internal semiconductive layer, a resin composition for a chemically crosslinkable polyethylene insulating layer on a conductor, and the peeling according to any one of the first to fourth inventions of the present invention. The step of sequentially coating the conductive semiconductive water-crosslinkable resin composition, the step of coating the internal semiconductive layer resin composition and the chemically crosslinkable polyethylene insulating layer resin composition is performed by a two-layer co-extrusion apparatus. And then a step of coating the releasable semiconductive water-crosslinkable resin composition with a chemically crosslinked polyethylene insulated power cable.

A sixth invention according to the present invention provides a resin composition for an internal semiconductive layer on a conductor, a resin composition for a chemically crosslinkable polyethylene insulating layer, and any one of the first to fourth inventions of the present invention. A method for producing a chemically crosslinked polyethylene insulated power cable, characterized in that the step of sequentially coating the releasable semiconductive water crosslinkable resin composition is performed by a three-layer coextrusion apparatus.

A seventh invention of the present invention is a chemically crosslinked polyethylene insulated power cable manufactured by the method of the fifth or sixth invention.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

1. Conductor and Internal Semi-Conducting Layer The conductor and the internal semi-conducting layer used in the present invention may be any as long as they are usually used in chemically crosslinked polyethylene insulated wires. Among them, as the conductor, for example, a conductor made of soft copper, semi-hard copper, hard copper, aluminum, or the like, a stranded conductor, or the like is preferable. Also, as the internal semiconductive layer,
For example, those obtained by blending carbon black or the like with a polyethylene copolymer such as an ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer are preferable. The reason polyethylene copolymers are preferred for the inner semiconductive layer is that a large amount of carbon black must be blended in order to make the inner semiconductive layer semiconductive. This is because they are superior in miscibility and dispersibility with carbon black and excellent in adhesion to conductors and insulating layers, as compared with the above resin. The role of the inner semiconductive layer is to improve the electric potential tendency and make the electric potential the same, thereby improving the withstand voltage performance. As a result, the life of the outdoor electric wire is prolonged.

As the carbon black to be blended for the inner semiconductive layer, conductive carbon blacks such as furnace black, acetylene black and Ketjen black can be used. The blending amount of carbon black is 8 to 100 parts by weight of carbon black with respect to 100 parts by weight of the polyethylene copolymer.
Parts by weight. If the blending amount of carbon black is less than 8 parts by weight, even if Ketjen black having good conductivity is used, the conductive performance is insufficient. On the other hand, if the blending amount of carbon black exceeds 100 parts by weight, economy is low. In addition, the extrudability and the surface properties are deteriorated, which is not desirable.

2. Chemically Crosslinked Polyethylene Insulation Layer The chemically crosslinked polyethylene insulation layer used in the present invention is a method in which a polyethylene resin, an organic peroxide, an antioxidant, and the like are charged into an insulating layer extruder (before the charge, the organic peroxide is added to the polyethylene resin. Or an antioxidant previously soaked, or a master batch of a polyethylene resin and an organic peroxide or an antioxidant may be added.), And heat-kneaded at 110 to 150 ° C. in an extruder. It is extruded from a die and heated to 200 to 300 ° C. in a crosslinked tube to form a chemically crosslinked polyethylene insulating layer.

The polyethylene resins include high-pressure low-density polyethylene, high-density polyethylene, medium-density polyethylene, linear low-density ethylene-α-olefin copolymer, and linear ultra-low-density ethylene-α-olefin copolymer. Polymer, ethylene-α- produced by metallocene catalyst
Olefin copolymers and the like can be mentioned.

Examples of the organic peroxide include dicumyl peroxide, di-t-butyl peroxide, 2,5
-Di (peroxybenzoate) hexin-3 and the like are used. The amount of organic peroxide used is polyethylene resin 1.
0.01 to 10.0 parts by weight based on 00 parts by weight is preferred.

Examples of the antioxidant include a phenolic antioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant and the like. About 0.001 to 5 parts by weight based on 100 parts by weight of the polyethylene resin. It is.

3. External semiconductive layer (1) Components of peelable semiconductive water crosslinkable resin composition The peelable semiconductive water crosslinkable resin composition for an external semiconductive layer of the present invention comprises the following (a) to (g). Consists of components. (A) (I) ethylene-vinyl acetate copolymer, (II)
Ethylene-ethyl acrylate copolymer, and (II)
I) One or more components selected from ethylene-butyl acrylate copolymer

(I) Ethylene-vinyl acetate copolymer The ethylene-vinyl acetate copolymer used in the present invention has a vinyl acetate content of 10 to 50% by weight, preferably 15 to 50% by weight.
% By weight, melt mass flow rate 1.0 to 100.0 g
/ 10 min. Vinyl acetate content is 10% by weight
If it is less than 1, peeling property, flexibility, elongation, carbon black filling property will be deteriorated, interface state, workability, etc. will be deteriorated, water tree and electric tree will be generated from the interface, and the life of the power cable will be shortened, which is not desirable. , More than 50% by weight, the tensile strength is weakened, the peeling operation is not successful, and the cable manufactured using this is not desirable because the surfaces stick together. Further, the melt mass flow rate is 1.0 g / 1.
If the time is less than 0 minutes, the workability, flexibility, elongation, etc. are insufficient, and if it exceeds 100.0 g / 10 minutes, the tensile strength, heat resistance, etc. deteriorate, which is not desirable.

(II) Ethylene-ethyl acrylate copolymer component The ethylene-ethyl acrylate copolymer used in the present invention has an ethyl acrylate content of 10 to 50% by weight, preferably 15 to 40% by weight, and a melt mass flow rate of 1.
It has a characteristic of 0 to 100.0 g / 10 minutes. When the content of ethyl acrylate is less than 10% by weight, the peeling property, flexibility, elongation, and carbon black filling property are deteriorated, the interface state, workability, etc. are deteriorated. However, the ethylene-ethyl acrylate copolymer exceeding 50% by weight has no physical problem, but is extremely difficult to produce. Further, if the melt mass flow rate is less than 1.0 g / 10 minutes, workability, flexibility, elongation, etc. are insufficient, and if it exceeds 100.0 g / 10 minutes, tensile strength, heat resistance, etc. become poor. Not desirable.

(III) Ethylene-butyl acrylate copolymer component The ethylene-butyl acrylate copolymer used in the present invention has a butyl acrylate content of 10 to 50% by weight, preferably 15 to 40% by weight, and a melt mass flow rate of 1.
It has a characteristic of 0 to 100.0 g / 10 minutes. When the butyl acrylate content is less than 10% by weight, the peeling property, flexibility, elongation, and carbon black filling property are deteriorated, the interface state, workability, and the like are deteriorated. The ethylene-butyl acrylate copolymer having an undesirably short life time and exceeding 50% by weight has no physical problem but is extremely difficult to produce. Further, if the melt mass flow rate is less than 1.0 g / 10 minutes, workability, flexibility, elongation, etc. are insufficient, and if it exceeds 100.0 g / 10 minutes, tensile strength, heat resistance, etc. become poor. Not desirable. Furthermore, (a) of the present invention
As the component, one or more selected from the above-mentioned (I) ethylene-vinyl acetate copolymer, (II) ethylene-ethyl acrylate copolymer and (III) ethylene-butyl acrylate copolymer are used. Can be used.

(B) Polypropylene Component The component (b) has a melt mass flow rate of 0.5 to 30.
0 g / 10 min, density 0.900 to 0.920 g / cm ³
Used to impart heat resistance and releasability to the outer semiconductive layer. If the melt mass flow rate of the component (b) is less than 0.5 g / 10 minutes, the processability is poor, and if it exceeds 30.0 g / 10 minutes, the tensile strength becomes weak, which is not desirable. If the density is less than 0.900 g / cm ³ , the heat resistance deteriorates, which is undesirable.
If it exceeds 0 g / cm ³ , the flexibility becomes poor, which is not desirable. Component (b) is used in an amount of 5 to 50 parts by weight, preferably 15 to 30 parts by weight, per 100 parts by weight of component (a). If the amount of the component (b) is less than 5 parts by weight, heat resistance and releasability will be insufficient. The polypropylene used in the present invention may be a propylene homopolymer or a copolymer of propylene and ethylene or another olefin as long as it has the above-mentioned physical properties.

(C) Organopolysiloxane Component The component (c) is represented by the following formula (A)

[0026]

Embedded image (Wherein, R ¹ is an aliphatic unsaturated hydrocarbon group, R ² is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group,
0 ≦ x <1, 0.5 <y <3, 1 <x + y <3, 0 <a
≦ 1, 0.5 ≦ b ≦ 3. ). In the organopolysiloxane represented by the formula (A), R ¹ is, for example, a vinyl group, an allyl group, an acryl group, a methacryl group, etc., and R ² is a methyl group, an ethyl group, a propyl group, etc. Alkyl group, phenyl group, aryl group such as tolyl group, cycloalkyl group such as cyclohexyl group and cyclobutyl group, and hydrogen partially bonded to carbon atom of these hydrocarbon groups such as halogen atom, cyano group, mercapto group, etc. And the like, and these may be the same or different combinations thereof. Also, a
When the value is 0, the reaction with the ethylene-based resin does not occur, which is not desirable. When it exceeds 1, the composition of the present invention becomes too hard, and the flexibility and processability decrease, which is not desirable. b is 0.
It is necessary to be 5 or more and 3 or less, preferably 1 or 2. If y is 0.5 or less, kneading of the composition of the present invention is difficult, resulting in poor processability. If y is 3 or more, the cable produced from the composition of the present invention becomes too hard, which is not desirable.

As long as the molecular structure of the organopolysiloxane used in the present invention is within the range of the formula (A), it may be any of linear, branched, cyclic, network, and three-dimensional networks. Good, but a chain is preferred. Although the degree of polymerization of this organopolysiloxane is not particularly limited,
A degree of polymerization that does not hinder kneading with the ethylene resin is required, and a degree of polymerization of 250 or more is desirable. The organopolysiloxane used in the present invention includes, for example, a so-called silicone gum stock which is commercially available as a material for improving the tear strength of silicone rubber. The linear organopolysiloxane used in the present invention has the following formula (B)

[0028]

Embedded image (Wherein, R represents an unsubstituted or substituted monovalent hydrocarbon group,
n represents a number of 10 or more. ) And generally called silicone oil. R in the formula is a group selected from an alkyl group, an aryl group, and hydrogen;
Methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, phenyl group and hydrogen are typical, but all groups are the same group. Or a part of R may be another group, and a part of R may be a vinyl group or a hydroxyl group. n is 10-1
0000, and preferably 100 to 1000. If n is less than 10, kneading with polyethylene is difficult,
If n exceeds 10,000, molding becomes difficult, which is not desirable.

The viscosity at 23 ° C. of the organopolysiloxane polymer of the formula (B) used in the present invention is 10 c
St or more, preferably 1,000 to 1,000,000
The one of cSt is desirable. When the viscosity is less than 10 cSt, it is difficult to knead by heating, and the organopolysiloxane polymer may ooze out from the surface of the molded article. The amount of the organopolysiloxane used is 0.5 to 50 parts by weight, preferably 2.0 to 50 parts by weight, per 100 parts by weight of the component (a).
Parts by weight, more preferably 2.0 to 10 parts by weight.
If the amount of the organopolysiloxane is less than 0.5 parts by weight, no releasability will be exhibited, and if it exceeds 50 parts by weight, workability, tensile strength and the like will be reduced, which is not desirable.

(D) Carbon black component The component (d) is carbon black, for example, furnace black, acetylene black, Ketjen black, etc. Among them, Ketjen black is particularly desirable. Ketchen Black is a Dutch AKZO
A highly conductive carbon black developed by NOBEL. There are two types, Ketjen Black EC and Ketjen Black EC600JD. Ketjen Black EC is 1/2 to that of conventional conductive carbon black. Since equivalent conductivity can be obtained with 1/3 of the additive, the tensile strength, workability, flexibility,
It is possible to provide a semiconductive resin composition of good quality with little decrease in conductive performance due to kneading without greatly affecting physical properties such as elongation and smoothness at an interface. The amount of carbon black used is (a) in the case of the first invention of the present invention, 7.0 to 350 parts by weight, preferably 7.0 to 300 parts by weight, more preferably 40 parts by weight, per 100 parts by weight of the components. To 200 parts by weight, and in the case of the second invention of the present invention, 7.0 to 350 × (1 + Q / 100) parts by weight, preferably 7.0 to 300 × (1 + Q / 100) parts by weight, more preferably 40 to 200 × (1 + Q / 100) parts by weight. Here, Q indicates the amount (parts by weight) of the component (h) described below, and the same applies to the following. If the amount of carbon black used is less than 7.0 parts by weight, the volume resistivity required for the outer semiconductive layer of the power cable is 1
It is more than 00 Ω · cm, which is not desirable. On the other hand, if it exceeds the above upper limit, the interface semi-conductivity, tensile strength, workability, flexibility, elongation, etc. of the external semiconductive layer are undesirably reduced.

(E) Unsaturated alkoxysilane component The unsaturated alkoxysilane of the component (e) is generally
Formula: RR'SiY₂  (In the formula, R is free radical generated in the polyethylene resin.
An aliphatic unsaturated hydrocarbon group reactive with dical or
A hydrocarbonoxy group, Y is an alkoxy group, R 'is water
Monovalent carbon containing no carbon atoms or olefinically unsaturated groups
Represents a hydride group. The alkoxysilane compound represented by)
It is. In the formula, as the aliphatic unsaturated hydrocarbon group for R,
For example, vinyl group, allyl group, butenyl group, cyclohexene
A vinyl group or a cyclopentadienyl group;
Particularly preferred is a phenyl group. Y is, for example, a methoxy group, ethoxy,
And a butoxy or butoxy group. Suitable unsaturated al
Coxysilane is γ-methacryloyloxypropyl
Trimethoxysilane, vinyltriethoxysilane and
It is vinyltrimethoxysilane.

The amount of the unsaturated alkoxysilane used is:
In the case of the first invention of the present invention, it is 0.5 to 20 parts by weight, preferably 0.5 part by weight, per 100 parts by weight of the component (a).
To 5.0 parts by weight, and in the case of the second invention of the present invention,
It is 0.5 to 20 × (1 + Q / 100) parts by weight, preferably 0.5 to 5.0 × (1 + Q / 100) parts by weight. If the amount of the unsaturated alkoxysilane is less than 0.5 part by weight, the degree of crosslinking of the outer semiconductive layer will be low, and the heat resistance and tensile strength will be insufficient. On the other hand, even if a large amount is blended beyond the above upper limit, not only the improvement in the degree of crosslinking does not appear remarkably, but also gasification occurs between the insulating layer and the external semiconductive layer, voids are generated and the quality of the cable deteriorates. In addition, unsaturated alkoxysilanes are expensive, which increases the cost and is not desirable.

(F) Organic peroxide component The organic peroxide of the component (f) generates free radical sites in the resin component under heating reaction conditions, and has a half-life of less than 6 minutes at the reaction temperature. Any compound having a half-life of preferably less than 1 minute can be used. The following are typical examples of the organic peroxide. However, the number in parentheses is the decomposition temperature (° C.). Succinic peroxide (110), benzoyl peroxide (110), t-butylperoxy-2-ethylhexanoate (113), p-chlorobenzoyl peroxide (115), t-butylperoxyisobutyrate (115) ), T-butylperoxyisopropyl carbonate (135), t-butylperoxyurearate (140), 2,5-dimethyl-2,5-di (benzoylperoxy) hexane (140), t-butylperoxy Acetate (140), di-t-butyl diperoxyphthalate (140), t-butyl peroxybenzoate (145), dicumyl peroxide (15
0), 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (155), t-butylcumyl peroxide (155), t-butylhydroperoxide (1
58), di-t-butyl peroxide (160), 2,
5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 (170), di-isopropylbenzene hydroperoxide (170), p-menthane hydroperoxide (180), 2,5-dimethylhexane -2,5
-Dihydroperoxide (213), cumene hydroperoxide (149). Among them, dicumyl peroxide, 2,5-dimethyl-2,5 (t-butylperoxy) hexane, cumene hydroperoxide and the like are desirable. In the case of the first invention of the present invention, the amount of the organic peroxide to be used is 0.05 to 4.
0 parts by weight, preferably 0.05 to 2.0 parts by weight, and in the case of the second invention of the present invention, 0.05 to 4.0 ×
(1 + Q / 100) parts by weight, preferably 0.05-2.
0 × (1 + Q / 100) parts by weight. When the amount of the organic peroxide is less than 0.05 parts by weight, the rate of grafting the unsaturated alkoxysilane to the resin component becomes low, the degree of crosslinking becomes insufficient, and the heat resistance and the tensile strength of the external semiconductive layer are reduced. Will be insufficient. On the other hand, if a large amount is blended beyond the above upper limit, a gel is generated, an outer semiconductive layer having a smooth surface cannot be obtained, water trees and electric trees are generated from the interface, and the life of the power cable is shortened, which is desirable. Absent.

(G) Silanol condensation catalyst component The silanol condensation catalyst of component (g) is a catalyst that hydrolyzes unsaturated alkoxysilanes grafted on the resin component of the present invention to promote a dehydration condensation reaction. Examples include dibutyltin dilaurate, dibutyltin diacetate, dibutyltin diolate, stannous acetate, lead naphthenate, cobalt naphthenate, zinc caprylate, iron 2-ethylhexanoate, titanate, and tetrabutyl titanate. , Tetranonyl titanate, bis (acetylacetonitrile) di-isopropyltitanium-ethylamine, hexylamine, dibutylamine, pyridine and the like. The amount of this silanol condensation catalyst used is
In the case of the first invention of the present invention, 0.01 to 20.0 parts by weight, preferably 0.5 part by weight, per 100 parts by weight of the component (a).
To 3.0 parts by weight, in the case of the second invention of the present invention,
It is 0.01 to 20 × (1 + Q / 100) parts by weight, preferably 0.5 to 3.0 × (1 + Q / 100) parts by weight.
When the amount of the silanol condensation catalyst used is less than 0.01 parts by weight, the water crosslinking reaction is not promoted.On the other hand, even when the amount exceeds the above upper limit, the water crosslinking reaction is not significantly improved. Instead, it deteriorates the electrical characteristics of the outer semiconductive layer,
Not desirable.

(H) Linear ethylene-α-olefin copolymer component (h) The component (h) is a component that is blended as required, and has a melt mass flow rate of 0.1 to 30.0 g / 10 min. 0.870 to 0.944 g / cm ³ of a linear ethylene-α-olefin copolymer. When the component (h) is blended, the resistance to heat deformation at 120 ° C. or higher further increases, and
This has the effect of further improving the extrusion of the outer semiconductive layer at high temperatures. (H) The melt mass flow rate of the component is 0.1
If it is less than g / 10 minutes, the processability will be poor, and 30.0%
If it exceeds g / 10 minutes, the tensile strength becomes weak, which is not desirable. Further, when the density is less than 0.870 g / cm ³ , the effect of improving the heat deformation resistance is lost, and 0.944 g / cm ³ is not obtained.
If it exceeds / cm ³ , flexibility is lost, which is not desirable.
Component (h) is used in an amount of 0 to 200 parts by weight, preferably 50 to 200 parts by weight, per 100 parts by weight of component (a). As the amount of the component (h) increases from 0 parts by weight, the resistance of the outer semiconductive layer to heat deformation at 120 ° C. improves, but if it exceeds 200 parts by weight, flexibility, elongation, and carbon black filling properties deteriorate. It is not desirable.

Examples of the linear ethylene-α-olefin copolymer of the component (h) include ethylene-α-olefin copolymers produced with a multi-site catalyst or a single-site catalyst. As the α-olefin, propylene, butene-1, hexene-1, 4-methyl-pentene-1, octene-1, nonene-1, decene-1 and the like are selectively used.

(I) Other components In the present invention, (a), (b), (c),
In addition to the components (d), (e), (f), (g) and (h), if necessary, (i) other components may be used depending on the purpose within a range that does not impair the characteristics of the present invention. , Crosslinking aid,
Anti-aging agents, processing aids, other polyolefin-based resins, thermoplastic elastomers, natural rubber, synthetic rubbers and the like may be used.

(2) Production of resin composition The above (a), (b), (c), (d), (e),
The components (f), (g) and, if necessary, the components (h) and (i) are, for example, in the following order and combination, a graft reaction, a compounding,
It can be manufactured by soaking or the like.

(A) a resin component selected from (a),
The resin component consisting of (b) and (c), (h) as an optional resin component, and carbon black (d) are heated and kneaded at 150 to 200 ° C. with an extruder or a Banbury, and the unsaturated alkoxysilane (e) is added thereto. , An organic peroxide (f) and a silanol condensation catalyst (g).
In which the unsaturated alkoxysilane is grafted to the resin component, and the carbon black (d) and the silanol condensation catalyst (g) are uniformly blended in the resin component.

(B) a resin component selected from (a),
(B) A resin component comprising (c), (h) as an optional resin component, carbon black (d) and a silanol condensation catalyst (g) are heated at 150 to 200 ° C. by an extruder or a Banbury.
And kneaded with heat, and the unsaturated alkoxysilane (e) and the organic peroxide (f) are added thereto.
A method in which the mixture is heated and kneaded at a temperature of 0 ° C., the unsaturated alkoxysilane is grafted to the resin component, and the carbon black (d) and the silanol condensation catalyst (g) are uniformly mixed in the resin component.

(C) a resin component selected from (a),
(B) The resin component comprising (c) and (h) as an optional resin component are heated and kneaded at 150 to 200 ° C. with an extruder or a Banbury, and the unsaturated alkoxysilane (e) and the organic peroxide ( f), then 200-250 ° C
To prepare a water-crosslinkable unsaturated alkoxysilane graft resin obtained by grafting the unsaturated alkoxysilane to the resin component. Meanwhile, a master batch of carbon black (d) and a master batch of silanol condensation catalyst (g) are prepared. When producing the outer semiconductive layer, the above three components are put into a hopper of an extruder for an outer semiconductive layer.

(D) a resin component selected from (a),
A resin component consisting of (b) and (c), (h) as an optional resin component, a resin component selected from a resin (a) soaked with unsaturated alkoxysilane (e), and an organic peroxide (f) Is kneaded with an extruder or Banbury at 200 to 250 ° C. to prepare a water-crosslinkable unsaturated alkoxysilane graft resin obtained by grafting an unsaturated alkoxysilane to a resin component. Meanwhile, a master batch of carbon black (d) and a master batch of silanol condensation catalyst (g) are prepared. When producing the outer semiconductive layer, the above three components are put into a hopper of an extruder for an outer semiconductive layer.

(E) a resin component selected from (a),
(B) a resin batch consisting of (c), (h) as an optional resin component, a masterbatch of carbon black (d),
The unsaturated alkoxysilane (e), the organic peroxide (f) and the silanol condensation catalyst (g) are simultaneously charged into a hopper of an extruder for an external semiconductive layer.

(F) The above (a), (b), (c),
In (d) and (e), other components are used as antioxidants (i) as they are, or as master batches, or as a mixture with unsaturated alkoxysilane (e) and organic peroxide (f). How to mix.

4. Jacket Layer The jacket layer of the chemically crosslinked polyethylene insulated power cable of the present invention is usually formed by extrusion-coating a polyvinyl chloride resin composition on an outer semiconductive layer. The jacket layer is formed by extruding the common semi-conductive layer, the chemically cross-linked polyethylene insulating layer and the external semi-conductive layer into three common layers, and then extruding and coating the polyvinyl chloride resin composition thereon.

5. Chemically crosslinked polyethylene insulated power cable The chemically crosslinked polyethylene insulated power cable of the present invention comprises a resin composition for an internal semiconductive layer, a resin composition for a chemically crosslinkable polyethylene insulating layer, and an external peelable semiconductive water crosslinkable resin on a conductor. It can be made by a step of sequentially coating the composition. To this, the resin composition for the internal semiconductive layer and the resin composition for a chemically crosslinkable polyethylene insulating layer are simultaneously extruded and coated in two layers by a two-layer coextrusion apparatus, and heated at 200 to 350 ° C. to chemically crosslink. A resin composition for the internal semiconductive layer, or a tandem method in which an external peelable semiconductive water-crosslinkable resin composition is coated, and water-crosslinked by contact with steam or hot water to form an external peelable semiconductive layer; The resin composition for the chemically crosslinkable polyethylene insulating layer and the externally peelable semiconductive water-crosslinkable resin composition are simultaneously extruded and coated in three layers by a three-layer simultaneous extrusion device, for example, sent to a cross-linking tube and heated using steam under heating conditions. Coating is carried out by heating at 200 to 350 ° C. to form a chemically crosslinked polyethylene insulating layer and a water crosslinkable externally peelable semiconductive resin layer. It made by.

[0047]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples. In addition, the test method in an Example is as follows. (1) Interface smoothness: The interface between the chemically crosslinked polyethylene insulating layer and the external semiconductive layer was visually judged. (2) Heat deformation ratio of outer semiconductive layer: 12 of outer semiconductive layer
The heat resistance at 0 ° C. was measured by the following method in accordance with the heating deformation test method of JISC3005. (A) Preparation of test piece The resin composition for an external semiconductive layer was heated and kneaded at 220 ° C., and the thickness was 2 mm, the length was 150 mm and the width was 180 by a hot press molding machine.
mm sheet, which is 15 mm wide and 30 m long
m was taken as a test specimen. (B) Measurement method A test piece was placed on a semicircular portion of a semicircular rod having a diameter of 5 mm, a parallel plate was placed on the test piece, and placed in an oven at 120 ° C. for 30 minutes.
After heating for 2 minutes, a pressure of 2 kg was applied from above the parallel plate to 3
After a lapse of 0 minutes, the thickness of the test piece was measured, and the rate of decrease in thickness was measured. (3) Peeling test of the outer semiconductive layer: It was carried out by the following method. (A) Preparation of test piece The chemically crosslinkable polyethylene resin composition was heated with a hot press machine (180 ° C., 30 minutes) to a thickness of 1.5 mm and a length of 150 m.
m, a chemically crosslinked sheet having a width of 180 mm was obtained. On the other hand, the resin composition for the external semiconductive layer is heated and kneaded at 180 ° C., and is 2.0 mm thick, 150 mm long and 180 mm wide by a hot press molding machine.
mm sheet was obtained. Both sheets were heated to 180 ° C, 15
At a pressure of MPa, a 3 mm sheet is formed.
Water crosslinking was performed at 24 ° C. in steam for 24 hours. A test piece having a width of 12.7 mm and a length of 120 mm was punched out of the two-layer sheet to obtain a test piece. (B) Test method Using a tensile tester, perform a peeling test at a pulling speed of 200 mm / min at 23 ° C. and determine the peel strength at which the external semiconductive layer is peeled at an angle of 180 ° C. with respect to the chemically crosslinked polyethylene layer. (Kg / 0.5 inch). (4) Tensile strength of the outer semiconductive layer: the resin composition for the outer semiconductive layer was heated and kneaded at 180 ° C, and a sheet having a thickness of 2.0 mm, a length of 150 mm, and a width of 180 mm was obtained with a hot press molding machine. Water-crosslinking was performed in water vapor at 80 ° C. for 24 hours to prepare a test piece, and the tensile strength was measured according to JIS K-6760. (5) Elongation of outer semiconductive layer: Elongation was measured according to JIS K-6760 using a test piece used for tensile strength. (6) Gel fraction of chemically crosslinked polyethylene insulating layer: A sample was taken from the chemically crosslinked polyethylene insulating layer, immersed in xylene at 110 ° C. for 24 hours, and the extraction residue was determined as the gel fraction. (7) Extrusion processability: The melt mass flow rate of the resin composition for the outer semiconductive layer was measured at a temperature of 190 using a melt indexer.
The melt mass flow rate was measured and evaluated under the conditions of ° C and a load of 21.6 kg (JIS K-6760). (8) Volume resistivity: The volume resistivity of the resin composition for an external semiconductive layer was measured by the method of JIS K-6723.

Example 1 (A) Preparation of Resin Composition for Internal Semiconductive Layer High-pressure ethylene-vinyl acetate having a vinyl acetate content of 28% by weight, a melt mass flow rate of 20.0 g / 10 minutes and a melting point of 91 ° C. With respect to 100 parts by weight of the copolymer, tetrakis [methylene-3- (3,5-di-
[t-butyl-4-hydroxyphenyl) propionate] 0.5 part by weight of methane (Irganox 1010 manufactured by Ciba Specialty Chemicals) and 80 parts by weight of acetylene black were blended, and kneaded at 130 ° C. for 10 minutes. A cylindrical pellet having a diameter of 3 mm and a height of 3 mm was obtained. Then, 0.5 parts by weight of 2,5-dimethyl-2,5-di (t-butylperoxin) hexyne, which is an organic peroxide, was added to the pellets.
The organic peroxide was uniformly impregnated into the inside of the pellet by stirring slowly for a time to prepare a resin composition for an internal semiconductive layer.

(B) Preparation of Resin Composition for Chemically Crosslinkable Polyethylene Insulating Layer High-pressure low-density polyethylene (density 0.92 g / cm ³ ,
100 parts by weight of a melt mass flow rate (3.2 g / 10 min) were mixed with organic peroxide 2,5-dimethyl-2,5-di (t-
1.6 parts by weight of butylperoxy) hexine (Perhexin 25B, manufactured by NOF CORPORATION), 4,4′-thiobis (6-t-butyl-3-methylphenol, an antioxidant (SEENOX BC manufactured by Cipro Kasei Co., Ltd.)
S)) A polyethylene resin composition containing 0.18 parts by weight was prepared as a resin composition for an insulating layer.

(C) Water-crosslinkable resin composition for external semiconductive layer A water-crosslinkable resin composition for external semiconductive layer comprising the following (a) to (i) was prepared by the following method. Component (a): vinyl acetate content 28% by weight, melt mass flow rate 20 g / 10 min, density 0.938 g / cm
100 parts by weight of ethylene-vinyl acetate copolymer ³ ) Component (b): melt mass flow rate 0.9 g / 10
20 parts by weight of polypropylene having a density of 0.900 g / cm ^{3 and} a component (c) having a viscosity of 300,000 cS at 23 ° C.
t, 5 parts by weight of silicone gum stock having a methyl vinyl silicone content of 1.0% (d) Component: Ketjen Black EC (manufactured by Mitsubishi Chemical Corporation)
30 parts by weight (e) Component: 2 parts by weight of vinyltriethoxysilane (A-151 manufactured by Nippon Unicar) (f) Component: 2,5-dimethyl-2,5-di (t-butylperoxy) hexine (Japan) Perhexin 25B manufactured by Yushi Co., Ltd.) 0.3 parts by weight (g) Component: 0.2 parts by weight of dibutyltin dilaurate (i) Component: tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) ) Propionate] methane (Irganox 1010 manufactured by Ciba Specialty Chemicals) 0.3 parts by weight Preparation method: Components (a), (b), (c) and (d) are heated and kneaded with a Banbury mixer at 180 ° C. for 10 minutes. And (e), (f), (g) and (i) components are added thereto,
Further, the mixture was heated and kneaded at 230 ° C. for 5 minutes to graft vinyl triethoxysilane to the resin component. The components were uniformly blended to form a pellet having a length of 3 mm and a diameter of 3 mm. This pellet was used in the following step (E) immediately after preparation.

(D) Preparation of Common Three-Layer Extrusion Apparatus Three extruders having screen packs of 150 mesh, 250 mesh, and 120 mesh respectively provided on a die plate are prepared, and these are connected to form an internal semiconductive device. The extruder had a common three-layer crosshead which was sequentially arranged as a layer extruder, an insulating layer extruder and an external semiconductive layer extruder.

(E) Production of Chemically Crosslinked Polyethylene Insulated Power Cable The resin composition for the inner semiconductive layer, the chemically crosslinkable polyethylene resin composition and the water crosslinkable resin for the outer semiconductive layer prepared in the above (A) to (C) Each component of the composition was fed to an internal semiconductive layer extruder, a chemically crosslinked polyethylene layer extruder and an external semiconductive layer extruder of a three-layer common extruder. After heating and kneading each of these components at 130 ° C. for the internal semiconductive layer extruder, 130 ° C. for the chemically crosslinked polyethylene layer extruder, and 220 ° C. for the external semiconductive layer extruder, each of them is passed through a three-layer common crosshead die. Coating was performed simultaneously on the hard copper stranded conductor so that the thickness of the inner semiconductive layer was 1 mm, the thickness of the chemically crosslinked polyethylene insulating layer was 4 mm, and the thickness of the outer semiconductive layer was 1 mm. Next, the chemical cross-linking reaction is completed with a cross-linking tube heated to 300 ° C., cooled and then exposed to steam at 80 ° C. for 24 hours to complete the water cross-linking reaction. After drying, the polyvinyl chloride compound is coated to a thickness of 3 mm. Then, the chemically crosslinked polyethylene insulated power cable of the present invention was manufactured as a jacket layer.

The results of the performance evaluation of the chemically crosslinked polyethylene insulated power cable of the present invention are shown below. (1) Interface smoothness: The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer was smooth and no protrusion exceeding 300 μm in diameter was observed. (2) Deformation rate due to heating of the outer semiconductive layer: The rate of decrease in thickness is 0.
The heat resistance was 8%, which was sufficient. (3) Peel test of outer semiconductive layer: Peel strength is 1.2
kg / 0.5 inch, and the peelability was sufficient. (4) Tensile strength of outer semiconductive layer: tensile strength is 16.3
MPa, indicating that it was not torn when the external semiconductive layer was peeled off. (5) Elongation of outer semiconductive layer: elongation is 458%,
It was shown that when the cable was bent, it could follow the bending sufficiently. (6) Gel fraction of the chemically cross-linked polyethylene insulating layer: The gel fraction was 82%, which was sufficiently chemically cross-linked, and the heat resistance was sufficient. (7) Extrudability: melt mass flow rate is 67 g
/ 10 minutes, and the extrusion processability was sufficient. (8) Volume resistivity: Volume resistivity is 33Ω · c
m, which was an appropriate numerical value.

Example 2 (A) Preparation of Resin Composition for Internal Semiconductive Layer High-pressure ethylene-ethyl acrylate copolymer having an ethyl acrylate content of 23% by weight, a melt mass flow rate of 10 g / 10 minutes and a melting point of 98 ° C. The antioxidant tetrakis [methylene-3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] methane (Irganox 1010 manufactured by Ciba Specialty Chemicals) 0.5 part by weight,
80 parts by weight of acetylene black is blended and
After kneading at 10 ° C. for 10 minutes, a cylindrical pellet having a diameter of 3 mm and a height of 3 mm was obtained. Next, 0.5 parts by weight of 2,5-dimethyl-2,5-di (t-tert-butylperoxy) hexyne, which is an organic peroxide, is added to the pellet, and the mixture is slowly stirred at 70 ° C. for 5 hours. In this way, the organic peroxide was uniformly impregnated into the inside of the pellet to prepare a resin composition for the internal semiconductive layer.

(B) Preparation of Resin Composition for Chemically Crosslinkable Polyethylene Insulating Layer High Pressure Method Low Density Polyethylene (Density 0.920 g / c
m ³ , melt mass flow rate 3.2 g / 10 min) 10
1.6 parts by weight of organic peroxide 2,5-dimethyl-2,5-di (t-butylperoxy) hexine (Perhexin 25B manufactured by NOF Corporation) was added to 0 parts by weight, and the antioxidants 4,4 ′ were used.
-Thiobis (6-t-butyl-3-methylphenol (Seanox BCS manufactured by Cipro Kasei Co., Ltd.
BCS)) A polyethylene resin composition containing 0.18 parts by weight was prepared as a resin composition for an insulating layer.

(C) Water-crosslinkable resin composition for external semiconductive layer Water-crosslinkable resin for external semiconductive layer comprising the following (a) to (i)
A fat composition was prepared by the following method. Component (a): ethyl acrylate content 32% by weight,
Lutmus flow rate 10 g / 10 min, density 0.941
g / cm³Ethylene-ethyl acrylate copolymer 1
00 parts by weight (b) component: melt mass flow rate 2.5 g / 10
Min, density 0.90g / cm ³Containing 5% by weight of ethylene
Propylene-ethylene copolymer 40 parts by weight Component (c): viscosity at 23 ° C. of 150,000 cS
t, silicone with a methyl vinyl silicone content of 0.7%
45 parts by weight of gum gum stock (d) Ingredient: Furnace Black (MMM Carbon Co., Ltd.)
 ENSACO 250G) 130 parts by weight (e) Component: vinyltriethoxysilane (Nihon Unicar
(A-151) 3.0 parts by weight (f) Component: 2,5-dimethyl-2,5-di (t-butyl)
Luperoxy) hexine (Perhexin manufactured by NOF Corporation)
25B) 1.2 parts by weight (g) Component: 0.15 parts by weight of dibutyltin dilaurate (i) Component: tetrakis [methylene-3- (3,5-di)
-T-butyl-4-hydroxyphenyl) propione
G] Methane (Ciba Specialty Chemicals Co., Ltd.
Luganox 1010) 0.3 part by weight Preparation method: (a), (b), (c), (d) and (g)
Heat the ingredients at 180 ° C for 10 minutes using a Banbury mixer.
Kneading, and adding (e), (f) and (i) components thereto,
Further heat and knead at 230 ° C for 5 minutes, vinyl triethoxy
Graft silane onto resin component and blend each component uniformly
The pellets were 3 mm in length and 3 mm in diameter. This
Immediately after preparation, are used in the following step (E).
Was.

(D) Preparation of Common Three-Layer Extrusion Apparatus Three extruders having screen plates of 150 mesh, 250 mesh, and 120 mesh respectively installed on a die plate are prepared, and these are connected to form an internal semiconductive device. The extruder had a common three-layer crosshead which was sequentially arranged as a layer extruder, an insulating layer extruder and an external semiconductive layer extruder.

(E) Production of Chemically Crosslinked Polyethylene Insulated Power Cable The resin composition for the inner semiconductive layer, the chemically crosslinkable polyethylene resin composition and the water crosslinkable resin for the outer semiconductive layer prepared in the above (A) to (C) Each component of the composition was fed to an internal semiconductive layer extruder, a chemically crosslinked polyethylene layer extruder and an external semiconductive layer extruder of a three-layer common extruder. After heating and kneading each of these components at 130 ° C. for the internal semiconductive layer extruder, 130 ° C. for the chemically crosslinked polyethylene layer extruder, and 220 ° C. for the external semiconductive layer extruder, each of them is passed through a three-layer common crosshead die. Coating was performed simultaneously on the hard copper stranded conductor so that the thickness of the inner semiconductive layer was 1 mm, the thickness of the chemically crosslinked polyethylene insulating layer was 4 mm, and the thickness of the outer semiconductive layer was 1 mm. This was passed through a cross-linking tube heated to 300 ° C. to chemically cross-link. Next, 24 hours in steam at 80 ° C.
After exposure to water, the water crosslinking reaction was completed, and after drying, the polyvinyl chloride compound was coated to a thickness of 3 mm to form a jacket layer, and the chemically crosslinked polyethylene insulated power cable of the present invention was manufactured.

The results of the performance evaluation of the chemically crosslinked polyethylene insulated power cable of the present invention are shown below. (1) Interface smoothness: The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer was smooth and no protrusion exceeding 300 μm in diameter was observed. (2) Deformation rate due to heating of the outer semiconductive layer: The rate of decrease in thickness is 0.
The heat resistance was 7%, which was sufficient. (3) Peel test of outer semiconductive layer: Peel strength is 1.1
kg / 0.5 inch, and the peelability was sufficient. (4) Tensile strength of outer semiconductive layer: The tensile strength is 13.1
MPa, indicating that it was not torn when the external semiconductive layer was peeled off. (5) Elongation of outer semiconductive layer: elongation is 432%,
It was shown that when the cable was bent, it could follow the bending sufficiently. (6) Gel fraction of the chemically cross-linked polyethylene insulating layer: The gel fraction was 59%, the cross-link was sufficiently chemically cross-linked, and the heat resistance was sufficient. (7) Extrudability: melt mass flow rate is 49 g
/ 10 minutes, and the extrusion processability was sufficient. (8) Volume resistivity: Volume resistivity is 35Ω · c
m, which was an appropriate numerical value.

Example 3 The same experiment as in Example 1 was carried out except that the resin composition comprising the following (a) to (i) was used instead of the resin composition of the outer semiconductive layer of Example 1. Was. Component (a): butyl acrylate content 17% by weight, melt mass flow rate 5 g / 10 minutes, density 0.937 g
/ Cm ³ of ethylene-butyl acrylate copolymer 10
0 parts by weight (b) component: melt mass flow rate 1.2 g / 10
7 parts by weight of polypropylene having a density of 0.910 g / cm ^{3 and} a component (c) having a viscosity of 3,000 cSt at 23 ° C.
And 30 parts by weight of dimethylpolysiloxane oil containing 0.8% of methyl vinyl silicone (d) Component: Ketjen Black EC (manufactured by Mitsubishi Chemical Corporation)
20 parts by weight Component (e): 5 parts by weight of vinyltriethoxysilane (A-151 manufactured by Nippon Unicar) Component (f): 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne (Japan) 1.8 parts by weight of Perhexin 25B manufactured by Yushi Co., Ltd. (g) Component: 1.2 parts by weight of dibutyltin dilaurate (i) Component: tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) ) Propionate] methane (Irganox 1010 manufactured by Ciba Specialty Chemicals) 0.3 part by weight Preparation method: (a), (b), (c), (d) and (i)
The components were supplied to a hopper of a single screw extruder with L / D = 32, φ = 75 mm, and a cylinder (abbreviated as C for cylinder) which coaxially surrounds the outside of the screw was heated and kneaded with the screw. At that time, the cylinder is 5
And each part of the cylinder from the extruder inlet to the outlet is sequentially C ₁ , C ₂ , C ₃ ,
Abbreviated as C ₄ and C ₅ , C ₁ , C ₂ , C ₃ , C ₄ , C
The temperatures of the _five parts were 160 ° C, 180 ° C, and 200 ° C, respectively.
° C., 220 ° C., and 220 ° C., at _{C 2} moiety,
(E), (f) and (g) were supplied, vinyltriethoxysilane was grafted to the resin component, and the components were uniformly blended to form a pellet having a diameter of 3 mm and a diameter of 3 mm.

The results are shown below. (1) Interface smoothness: The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer was smooth and no protrusion having a diameter of 300 μm or more was observed. (2) Heat resistance of the external semiconductive layer: The reduction rate was 1.0%, and the heat resistance was sufficient. (3) Peeling test of outer semiconductive layer: Peeling strength is 1.7k
g / 0.5 inch, and the releasability was sufficient. (4) The tensile strength of the outer semiconductive layer was 11.7 MPa, which indicated that the outer semiconductive layer was not torn when peeled. (5) Elongation of the outer semiconductive layer: 485%, indicating that when the cable is bent, it can sufficiently follow the bending. (6) Gel fraction of chemically crosslinked polyethylene insulating layer: 82%
And the composition was sufficiently chemically crosslinked and had sufficient heat resistance. (7) Extrudability: melt mass flow rate (temperature 19)
(0 ° C., load 21.6 kg) was 82 g / 10 minutes, and the extrusion processability was sufficient. (8) Volume specific resistance: 45 Ω · cm, which was an appropriate value.

Example 4 In place of the water-crosslinkable resin composition for an outer semiconductive layer of Example 1,
Then, a resin composition comprising the following (a) to (i) was used.
Except for this, the same experiment as in Example 1 was performed. Component (a): vinyl acetate content 45% by weight, melt mass
Flow rate 20 g / 10 min, density 0.945 g / cm
³100 parts by weight of ethylene-vinyl acetate copolymer of (b) component: melt mass flow rate 10 g / 10 minutes,
Density 0.900g / cm ³10 parts by weight of polypropylene (c) component: the viscosity at 23 ° C. is 800,000 cS
t, silicone having a methylvinylsilicone content of 1.0%
5 parts by weight of gum gum stock (d) Ingredient: Ketjen Black EC (Mitsubishi Chemical Corporation)
40 parts by weight (e) component: vinyltriethoxysilane (Nihon Unicar
(A-151) 7 parts by weight Component (f): 2,5-dimethyl-2,5-di (t-butyl)
Luperoxy) hexine (Nippon Yushi Co., Ltd .: Perhexine)
25B) 4.3 parts by weight (g) Component: 5 parts by weight of dibutyltin dilaurate (h) Component: melt mass flow rate 0.8 g / 10
Min, density 0.922g / cm³Manufactured by gas-phase low-pressure method
180 weight of the prepared linear ethylene-butene-1 copolymer
Part (i) Component: tetrakis [methylene-3- (3,5-di
Tert-butyl-4-hydroxyphenyl) propionate
G] methane (Ciba Specialty Chemicals Il
Ganox 1010) 0.3 parts by weight Preparation method: (a), (b), (c), (d) and (h)
Heat the ingredients at 180 ° C for 10 minutes using a Banbury mixer.
Kneaded, and the components (e), (f), (g) and (i)
And kneaded by heating at 230 ° C for 5 minutes.
Ethoxysilane is grafted to resin components, and each component is homogenized
Into pellets with a length of 3 mm and a diameter of 3 mm
Was.

The results are shown below. (1) Interface smoothness: The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer was smooth and no protrusion having a diameter of 300 μm or more was observed. (2) Heat resistance of the outer semiconductive layer: The reduction rate was 0.5%, and the heat resistance was sufficient. (3) Peel test of outer semiconductive layer: Peel strength is 0.8k
g / 0.5 inch, and the releasability was sufficient. (4) The tensile strength of the outer semiconductive layer was 18.3 MPa, which indicated that the outer semiconductive layer was not torn when peeled. (5) Elongation of the outer semiconductive layer: 475%, indicating that when the cable is bent, it can sufficiently follow the bending. (6) Gel fraction of chemically crosslinked polyethylene insulating layer: 82%
And the composition was sufficiently chemically crosslinked and had sufficient heat resistance. (7) Extrudability: melt mass flow rate (temperature 19)
(0 ° C., load 21.6 kg) was 37 g / 10 minutes, and the extrusion processability was sufficient. (8) Volume resistivity: 41 Ω · cm, which was an appropriate value.

Example 5 The procedure of Example 1 was repeated, except that the water-crosslinkable resin composition for an external semiconductive layer was replaced.
Then, a resin composition comprising the following (a) to (i) was used.
Except for this, the same experiment as in Example 1 was performed. Component (a): ethyl acrylate content 35% by weight,
Lutmas flow rate 15 g / 10 min, density 0.941
g / cm³Ethylene-ethyl acrylate copolymer 1
00 parts by weight (b) component: melt mass flow rate 15 g / 10 minutes,
Density 0.900g / cm ³40 parts by weight of polypropylene (c) component: viscosity at 23 ° C. of 100,000 cS
t, silicone with 1.5% methylvinylsilicone content
45 parts by weight of gum gum stock (d) Ingredient: Ketjen Black EC (Mitsubishi Chemical Corporation)
200 parts by weight (e) component: vinyltrimethoxysilane (Nihon Unicar
A-171) 2 parts by weight (f) Component: 2,5-dimethyl-2,5-di (t-butyl)
Luperoxy) hexine (Perhexin manufactured by NOF Corporation)
25B) 1.3 parts by weight (g) component: 0.8 parts by weight of dibutyltin dilaurate (h) component: melt mass flow rate 10 g / 10 minutes,
Density 0.930g / cm ³Produced by metallocene catalyst
20 parts by weight of the obtained linear ethylene-octene-1 copolymer (i) Component: tetrakis [methylene-3- (3,5-di)
-T-butyl-4-hydroxyphenyl) propione
G] Methane (Ciba Specialty Chemicals Co., Ltd.
Luganox 1010) 0.3 part by weight Preparation method: (a), (b), (c), (d) and (h)
Heat the ingredients at 180 ° C for 10 minutes using a Banbury mixer.
Kneaded, and the components (e), (f), (g) and (i)
And kneaded by heating at 230 ° C for 5 minutes.
Ethoxysilane is grafted to resin components, and each component is homogenized
Into pellets with a length of 3 mm and a diameter of 3 mm
Was.

The results are shown below. (1) Interface smoothness: The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer was smooth and no protrusion having a diameter of 300 μm or more was observed. (2) Heat resistance of the outer semiconductive layer: The reduction rate was 0.9%, and the heat resistance was sufficient. (3) Peel test of outer semiconductive layer: Peel strength is 1.1k
g / 0.5 inch, and the releasability was sufficient. (4) The tensile strength of the outer semiconductive layer was 14.8 MPa, which indicated that the outer semiconductive layer was not torn when peeled. (5) Elongation of the outer semiconductive layer: 428%, indicating that when the cable is bent, it can sufficiently follow the bending. (6) Gel fraction of chemically crosslinked polyethylene insulating layer: 59%
And the composition was sufficiently chemically crosslinked and had sufficient heat resistance. (7) Extrudability: melt mass flow rate (temperature 19)
(0 ° C., load 21.6 kg) was 46 g / 10 minutes, and the extrusion processability was sufficient. (8) Volume resistivity: 46 Ω · cm, which was an appropriate value.

Example 6 In place of the water-crosslinkable resin composition for an external semiconductive layer of Example 1,
Then, a resin composition comprising the following (a) to (i) was used.
Except for this, the same experiment as in Example 1 was performed. Component (a): butyl acrylate content 17% by weight,
Lumber mass flow rate 7g / 10min, density 0.932g
/ Cm³Ethylene-butyl acrylate copolymer 10
0 parts by weight (b) component: melt mass flow rate 10 g / 10 minutes,
Density 0.900g / cm ³20 parts by weight of polypropylene (c) component: viscosity at 23 ° C. of 300,000 cS
t, silicone having a methyl vinyl silicone content of 1.2%
5 parts by weight of gum gum stock (d) Ingredient: Ketjen Black EC (Mitsubishi Chemical Corporation)
20 parts by weight (e) component: vinyltrimethoxysilane (Nihon Unicar
A-171) 3 parts by weight (f) Component: 2,5-dimethyl-2,5-di (t-butyl)
Luperoxy) hexine (Perhexin manufactured by NOF Corporation)
25B) 1.2 parts by weight (g) Component: 0.1 part by weight of dibutyltin dilaurate (h) Component: Melt mass flow rate 8 g / 10 minutes, dense
Produced by a metallocene catalyst having a degree of 0.920 g / ml.
5 parts by weight of a linear ethylene-hexene-1 copolymer (i) Component: tetrakis [methylene-3- (3,5-di
-T-butyl-4-hydroxyphenyl) propione
G] Methane (Ciba Specialty Chemicals Co., Ltd.
Luganox 1010) 0.3 part by weight Preparation method: (a), (b), (c), (d) and (h)
Heat the ingredients at 180 ° C for 10 minutes using a Banbury mixer.
Kneaded, and the components (e), (f), (g) and (i)
And kneaded by heating at 230 ° C for 5 minutes.
Ethoxysilane is grafted to resin components, and each component is homogenized
Into pellets with a length of 3 mm and a diameter of 3 mm
Was.

The results are shown below. (1) Interface smoothness: The interface between the chemically cross-linked polyethylene insulating layer and the outer semiconductive layer was smooth and no protrusion having a diameter of 300 μm or more was observed. (2) Heat resistance of the external semiconductive layer: The reduction rate was 1.2%, and the heat resistance was sufficient. (3) Peeling test of outer semiconductive layer: peeling strength is 1.2k
g / 0.5 inch, and the releasability was sufficient. (4) The tensile strength of the outer semiconductive layer was 13.6 MPa, which indicated that the outer semiconductive layer was not torn when peeled. (5) Elongation of the outer semiconductive layer: 483%, indicating that the cable can sufficiently follow the bending when bent. (6) Gel fraction of chemically crosslinked polyethylene insulating layer: 82%
And the composition was sufficiently chemically crosslinked and had sufficient heat resistance. (7) Extrudability: melt mass flow rate (temperature 19)
(0 ° C., load 21.6 kg) was 32 g / 10 minutes, and the extrusion processability was sufficient. (8) Volume resistivity: 65 Ω · cm, which was an appropriate value.

Comparative Example 1 An experiment was carried out in the same manner as in Example 1 except that the ethylene-vinyl acetate copolymer (EVA) in (a) was replaced with EVA having a vinyl acetate content of 8%. Where
The flexibility and elongation of the outer semiconductive layer deteriorated.

Comparative Example 2 The same experiment as in Example 1 was performed, except that the ethylene-vinyl acetate copolymer (EVA) of (a) was replaced with EVA having a vinyl acetate content of 55%. As a result, the tensile strength of the outer semiconductive layer was weakened, and the operation of peeling the outer semiconductive layer was not successful.

Comparative Example 3 In Example 1, the ethylene-vinyl acetate copolymer (EVA) of (a) was prepared by adding 0.8 g of a melt mass flow rate.
The same experiment as in Example 1 was performed except that EVA was replaced with EVA for / 10 minutes. As a result, the extrudability, flexibility, elongation, and the like of the outer semiconductive layer were insufficient.

Comparative Example 4 In Example 1, the ethylene-vinyl acetate copolymer (EVA) of (a) was melted at a melt mass flow rate of 120 g.
When an experiment similar to that of Example 1 was performed except that EVA was replaced with EVA of / 10 min, the tensile strength and heat resistance of the external semiconductive layer were insufficient.

Comparative Example 5 An experiment was carried out in the same manner as in Example 4 except that the ethylene-butene-1 copolymer (h) was replaced with one having a melt mass flow rate of 0.08 g / 10 min. The workability of the external semiconductive layer deteriorated.

Comparative Example 6 An experiment was carried out in the same manner as in Example 4 except that the ethylene-butene-1 copolymer (h) was replaced by one having a melt mass flow rate of 35.0 g / 10 minutes. Was performed, the tensile strength of the external semiconductive layer became weak.

Comparative Example 7 The same experiment as in Example 4 was performed, except that the ethylene-butene-1 copolymer (h) was replaced with one having a density of 0.850 g / cm ^3. As a result, the heat-deformation resistance of the outer semiconductive layer at 120 ° C. or higher deteriorated.

Comparative Example 8 An experiment was conducted in the same manner as in Example 4 except that the ethylene-butene-1 copolymer (h) was replaced with one having a density of 0.948 g / cm ^3. As a result, the flexibility of the external semiconductive layer deteriorated.

Comparative Example 9 Example 4 was repeated except that the amount of the ethylene-butene-1 copolymer (h) was changed to 220 parts by weight.
When the same experiment was performed, the adhesion of the external semiconductive layer was
Flexibility, elongation, and fillability of carbon black deteriorated.

Comparative Example 10 An experiment was carried out in the same manner as in Example 1 except that the polypropylene of (b) was replaced with one having a melt mass flow rate of 0.3 g / 10 min. The workability of the conductive layer deteriorated.

Comparative Example 11 An experiment was carried out in the same manner as in Example 1 except that the polypropylene of (b) was replaced with one having a melt mass flow rate of 33.0 g / 10 min. The tensile strength of the conductive layer became weak.

Comparative Example 12 In Example 1, the polypropylene of (b) was prepared by adding a melt mass flow rate of 2.0 g / 10 minutes and a density of 0.8.
When an experiment similar to that of Example 1 was performed except that the thickness of the external semiconductive layer was changed to 95 g / cm ³ , the heat deformation rate of the external semiconductive layer at 120 ° C. or more was deteriorated.

Comparative Example 13 The same procedure as in Example 1 was repeated except that the polypropylene of (b) was prepared by adding a melt mass flow rate of 5.4 g / 10 min and a density of 0.9.
The same experiment as in Example 1 was performed except that the thickness was changed to 25 g / cm ³ , and the flexibility of the external semiconductive layer was deteriorated.

Comparative Example 14 An experiment was conducted in the same manner as in Example 1 except that the amount of the polypropylene (b) was changed to 3 parts by weight. Peelability was insufficient.

Comparative Example 15 An experiment was conducted in the same manner as in Example 1 except that the amount of the polypropylene (b) was changed to 55 parts by weight. Sex deteriorated.

Comparative Example 16 An experiment was conducted in the same manner as in Example 1 except that the amount of the silicone gum stock (c) was changed to 0.3 parts by weight. Plane smoothness and peelability were insufficient.

Comparative Example 17 An experiment was conducted in the same manner as in Example 1 except that the amount of the silicone gum stock (c) was changed to 55 parts by weight. The smoothness deteriorated and the tensile strength was insufficient.

Comparative Example 18 An experiment was carried out in the same manner as in Example 1 except that the amount of Ketjen black used in (d) was changed to 5 parts by weight. 200 resistance
Ω · cm.

Comparative Example 19 An experiment was conducted in the same manner as in Example 1 except that the amount of the vinyltriethoxysilane (e) was changed to 0.3 part by weight. Had insufficient heat resistance and tensile strength.

Comparative Example 20 An experiment was conducted in the same manner as in Example 1 except that the amount of vinyltriethoxysilane (e) was changed to 25 parts by weight. Many projections of 300 μm or more were generated, and the life of the power cable was shortened.

Comparative Example 21 In Example 1, the amount of the organic peroxide (f) was changed to 0.0
When an experiment similar to that of Example 1 was performed except that the amount was changed to 01 parts by weight, the heat resistance and the tensile strength of the outer semiconductive layer were insufficient.

Comparative Example 22 An experiment was conducted in the same manner as in Example 1 except that the amount of the organic peroxide (f) was changed to 5 parts by weight. Many projections were generated, and a smooth surface could not be obtained.

Comparative Example 23 An experiment was conducted in the same manner as in Example 1 except that the amount of dibutyltin dilaurate (g) was changed to 0.005 parts by weight. The properties and tensile strength were insufficient.

Comparative Example 24 An experiment was conducted in the same manner as in Example 1 except that the amount of dibutyltin dilaurate (g) was changed to 24 parts by weight. As a result, many projections of 300 μm or more were generated on the surface of the external semiconductive layer, and the life of the power cable was shortened.

[0092]

According to the present invention, there is provided a peelable semiconductive resin composition used as an outer semiconductive layer of a chemically crosslinked polyethylene insulated power cable, comprising a specific ethylene-vinyl acetate copolymer and ethylene-ethyl acrylate copolymer. Coalescing,
Ethylene copolymer selected from ethylene-butyl acrylate copolymer, etc., polypropylene, organopolysiloxane, ethylene-α-olefin copolymer as an optional component, etc. are used as resin components, and these resin components are unsaturated. Contains alkoxysilane, organic peroxide, carbon black, and silanol catalyst, so when coated as an external semiconductive layer, it is cross-linked with water and has appropriate semiconductivity, peelability, tensile strength, adhesion, and processing. Properties, surface smoothness,
Excellent in cold resistance, heat resistance, etc., and particularly superior in tensile strength and heat resistance compared to conventional products.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/5425 C08K 5/5425 C08L 23/08 C08L 23/08 23/12 23/12 83/04 83 / 04 H01B 9/02 H01B 9/02 B 13/14 13/14 A (72) Inventor Koji Ishihara 7-16-12 Ehara, Shinagawa-ku, Tokyo F-term (reference) 4J002 BB05Z BB06W BB07W BB12X BB14X BB15X CP03Y DA036 EG049 EK0008 EK028 EK038 EK048 EK058 EX017 FD116 FD148 FD207 FD209 GQ01 4J026 AA12 AA13 AB44 AC04 AC07 AC19 BA43 BB01 DB05 DB13 DB15 FA03 FA09 GA07 5G301 DA18 DA42 DA43 DA45 DD04 5G325 GA01 GC06 GC10

Claims (7)

[Claims] 1. Use as an outer semiconductive layer of a chemically crosslinked polyethylene insulated power cable in which an inner semiconductive layer, a chemically crosslinked polyethylene insulating layer, an outer semiconductive layer and a jacket layer are formed on a conductor from inside to outside. A releasable semiconductive water-crosslinkable resin composition comprising the following components (a), (b), (c), (d), (e), (f) and (g). (A) (I) an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 50% by weight and a melt mass flow rate of 1.0 to 100.0 g / 10 minutes, and (II) an ethyl acrylate content of 10 to 50% by weight. Ethylene-ethyl acrylate copolymer having a melt mass flow rate of 1.0 to 100.0 g / 10 min, and (III) a butyl acrylate content of 10 to 50% by weight, and a melt mass flow rate of 1.0 to 100.0 g / 10 min. At least one selected from ethylene-butyl acrylate copolymers
00 parts by weight (b) Melt mass flow rate 0.5-30.0 g / 1
0 min, 5 to 50 parts by weight of polypropylene having a density of 0.900 to 0.920 g / cm ³ (c) the following formula (A) (Wherein, R ¹ is an aliphatic unsaturated hydrocarbon group, R ² is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group,
0 ≦ x <1, 0.5 <y <3, 1 <x + y <3, 0 <a
≦ 1, 0.5 ≦ b ≦ 3. 0.5 to 50 parts by weight of an organopolysiloxane represented by the formula (d): 7.0 to 350 parts by weight of carbon black (e) 0.5 to 20.0 parts by weight of an unsaturated alkoxysilane (f) Organic peroxide 0 0.05 to 4.0 parts by weight (g) 0.01 to 20.0 parts by weight of a silanol condensation catalyst 2. Use as an outer semiconductive layer of a chemically crosslinked polyethylene insulated power cable having an inner semiconductive layer, a chemically crosslinked polyethylene insulating layer, an outer semiconductive layer and a jacket layer formed on a conductor from inside to outside. The following (a), (b), (c), (d), (e), (f),
A peelable semiconductive water-crosslinkable resin composition comprising the components (g) and (h). (A) (I) an ethylene-vinyl acetate copolymer having a vinyl acetate content of 10 to 50% by weight and a melt mass flow rate of 1.0 to 100.0 g / 10 minutes, and (II) an ethyl acrylate content of 10 to 50% by weight. Ethylene-ethyl acrylate copolymer having a melt mass flow rate of 1.0 to 100.0 g / 10 min, and (III) a butyl acrylate content of 10 to 50% by weight, and a melt mass flow rate of 1.0 to 100.0 g / 10 min. At least one selected from ethylene-butyl acrylate copolymers
00 parts by weight (b) Melt mass flow rate 0.5-30.0 g / 1
0 min, 5 to 50 parts by weight of polypropylene having a density of 0.900 to 0.920 g / cm ³ (c) the following formula (A): (Wherein, R ¹ is an aliphatic unsaturated hydrocarbon group, R ² is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group,
0 ≦ x <1, 0.5 <y <3, 1 <x + y <3, 0 <a
≦ 1, 0.5 ≦ b ≦ 3. (D) carbon black 7.0 to 350 × (1 + Q / 1)
00) parts by weight (e) unsaturated alkoxysilane 0.5 to 20 × (1 + Q)
/ 100) parts by weight (f) Organic peroxide 0.05 to 4.0 × (1 + Q / 10
0) parts by weight (g) Silanol condensation catalyst 0.01-20 × (1 + Q /
100) parts by weight (h) Melt mass flow rate 0.1 to 30.0 g / 1
0 minutes, 0 to 200 parts by weight of a linear ethylene-α-olefin copolymer having a density of 0.870 to 0.944 g / cm ³ .
(However, Q is the amount (parts by weight) of the component (h).) 3. The method according to claim 1, wherein the resin composition comprising (a), (b) and (c) and the carbon black component of (d) are 15
The mixture is heated and kneaded at 0 to 200 ° C., and the unsaturated alkoxysilane (e), the organic peroxide of (f) and the silanol condensation catalyst of (g) are blended therein, and then kneaded at 200 to 250 ° C. Chemically cross-linked polyethylene insulated power with an inner semi-conductive layer, chemically cross-linked polyethylene insulating layer, outer semi-conductive layer and jacket layer formed from inside to outside on a conductor made by grafting an unsaturated alkoxysilane to a resin component A peelable semiconductive water-crosslinkable resin composition used as an external semiconductive layer of a cable. 4. The resin composition comprising (a), (b), (c) and (h) of claim 2 and the carbon black component of (d) are heated and kneaded at 150 to 200 ° C. The unsaturated alkoxysilane of e), the organic peroxide of (f) and the silanol condensation catalyst of (g) are blended.
An internal semiconductive layer, a chemically crosslinked polyethylene insulating layer, an external semiconductive layer, and a jacket layer are formed from inside to outside on a conductor made by heating and kneading at ~ 250 ° C and grafting an unsaturated alkoxysilane to a resin component. A releasable semiconductive water-crosslinkable resin composition for use as an outer semiconductive layer of a chemically crosslinked polyethylene insulated power cable. 5. A resin composition for an internal semiconductive layer, a resin composition for a chemically crosslinkable polyethylene insulating layer on a conductor, and
5. The step of sequentially coating the releasable semiconductive water-crosslinkable resin composition according to any one of the above-described items 4, the step of coating the resin composition for an internal semiconductive layer and the resin composition for a chemically crosslinkable polyethylene insulating layer. Is carried out by a two-layer coextrusion apparatus, and then a step of coating the releasable semiconductive water-crosslinkable resin composition is carried out. 6. A resin composition for an inner semiconductive layer, a resin composition for a chemically crosslinkable polyethylene insulating layer on a conductor, and
5. A method for producing a chemically crosslinked polyethylene insulated power cable, wherein the step of sequentially coating the releasable semiconductive water crosslinkable resin composition according to any one of items 4 to 4 is performed by a three-layer coextrusion apparatus. 7. A chemically cross-linked polyethylene insulated power cable manufactured by the method of claim 5.