JP5183365B2 - Polyethylene resin material for non-crosslinked electric wires and electric wires and cables using the same - Google Patents

Description

  The present invention relates to a resin material for electric wires / cables for electric power transmission and electric wires / cables using the same, and more particularly, maintains a preferable allowable conductor temperature, has excellent durability, and is recycled in a non-crosslinked type. The present invention relates to a possible polyethylene resin material and an electric wire / cable (also referred to as a power cable) using the same as an insulator.

Conventionally, as a power cable, a cross-linked polyethylene cable using a cross-linked polyethylene obtained by cross-linking low-density polyethylene as an insulator is widely used. The purpose of using cross-linked polyethylene is to improve the heat resistance of low-density polyethylene and to improve the durability when stress is generated.By improving the heat resistance by cross-linking, the allowable temperature of the conductor can be increased and the transmission capacity can be increased. It is because it becomes advantageous.
General specifications of the above-mentioned crosslinked polyethylene cable, for example, a crosslinked polyethylene insulator defined in JIS C3605, 600V polyethylene cable, is specified to have a heat resistance of 120 ° C. × 30 minutes, a load of 10 N and a deformation of 40% or less. ing.

Moreover, in this polyethylene cable, F50 needs to have 1000 hr or more as durability in the environmental stress test (ESCR) prescribed | regulated to JISK6922.
Furthermore, when the surface of the electric wire is processed, unevenness on the surface affects transmission characteristics and wear resistance, so that melt fracture does not need to occur even at high shear rates. As one guideline, it is required that melt fracture does not occur even at a high speed molding such as 1000 sec ⁻¹ at 190 ° C.
In addition, these cross-linked polyethylene cables are often incinerated or landfilled because the insulator is cross-linked. As a result, in the air pollution and landfill caused by incineration, Increasing the environmental load, such as being left semi-permanently, has become a problem.

On the other hand, for power cables using non-crosslinked polyethylene as an insulator, for example, a copolymer of low-density polyethylene and dibasic acid anhydride obtained by high-pressure radical polymerization, or low-density polyethylene obtained by high-pressure radical polymerization In addition, a study has been made on a power cable which is a copolymer grafted with a dibasic acid anhydride and has an ethylene copolymer with a dibasic anhydride group content of 0.002 to 0.05% by weight as an insulator. Patent Document 1 and the like have been proposed.
The electric power cable proposed in Patent Document 1 can dramatically increase the electric insulation resistance without increasing the dielectric loss tangent, so that the power loss during high-voltage power transmission can be reduced without increasing the thickness of the insulating layer. It can be made to.
However, since low-density polyethylene, which is difficult to heat resistance, is used as the base polymer of the insulator, there is room for further improvement in order to increase the transmission capacity by increasing the high-temperature characteristics, particularly the allowable conductor temperature. Is left.

For example, Patent Documents 2 to 7 have been proposed as a composition of a high-density polyethylene resin and an ethylene / α-olefin copolymer produced by a single site catalyst.
In these patent documents, it is described that it is suitable mainly for the production of a film having excellent film appearance and transparency. However, as a power cable like the present invention, a cross fractionation chromatograph (hereinafter referred to as CFC) is described. However, it does not suggest or disclose the excellent durability due to the specific elution amount of the component, the necessity of the conductor allowable temperature, and the like.
Japanese Patent Laid-Open No. 05-205529 Japanese Patent Laid-Open No. 08-283477 Japanese Patent Laid-Open No. 08-291235 Japanese Patent Laid-Open No. 09-087439 JP 09-087440 A Japanese Patent Laid-Open No. 10-073538 JP-T-2004-501259

  In view of the above problems, an object of the present invention is a power cable using non-crosslinked polyethylene as an insulator, which significantly improves the allowable temperature of conductors based on conventional low-density polyethylene and maintains high-temperature dielectric breakdown characteristics. An object of the present invention is to provide a power cable that can be used for recycling an insulator when disposed as a removed power cable.

As a result of intensive studies to solve the above problems, the present inventors have found that the above-mentioned problems can be solved by using a specific non-crosslinked polyethylene instead of the above-mentioned crosslinked polyethylene. Is.
That is, medium density polyethylene or high density polyethylene having a high degree of crystallinity has heat resistance equivalent to that of the above-mentioned crosslinked polyethylene, and power cables using these medium density or high density polyethylene as insulators are conventional general-purpose cables. Even when compared with a conventional cross-linked polyethylene power cable, a conductor allowable temperature comparable to that of a conventional cross-linked polyethylene power cable is obtained, and when it is disposed as a removed cable, the insulator can be recycled.
However, when the degree of crystallinity is increased, the durability against stress generally deteriorates significantly, so that it has not been put into practical use, but by using a resin material in which a specific elution amount by CFC is in a specific range, It has become possible to solve this problem.
In particular, it has been found that the object of the present invention can be easily achieved by combining a specific high density polyethylene and a specific ultra-low density ethylene / α-olefin copolymer having a narrow molecular weight distribution. Based on these findings, the present inventors have completed the present invention.

That is, according to the first invention of the present invention, there is provided a polyethylene resin material (A) for non-crosslinked electric wires which satisfies at least the following requirements (a1) to (a3).
(A1) Melt flow rate (MFR) measured under condition D (temperature 190 ° C., load 21.18 N) based on the test method of JIS K6922-1 (1997) is 0.15 to 5.0 g / 10 min. ,
(A2) The density measured based on the test method of JIS K6922-1 (1997) is 0.925 to 0.945 g / cm ³ ,
(A3) Satisfy the following requirements (i) to (iii) measured by a cross-fractionation chromatograph (CFC).
(I) Elution amount of 40 ° C. or lower: 5 to 50% by weight
(Ii) Amount of components having a log molecular weight of 5.5 or more that elutes at 94 ° C. or less: greater than 0.1 and 5% by weight or less (iii) Amount of elution at 96 ° C. or less: 95% by weight or less

According to the second invention of the present invention, in the first invention, the polyethylene resin material (A) for non-crosslinked electric wire has (b1) MFR of 0.1 to 1.0 g / 10 min, (b2) High density polyethylene (B) having a density of 0.950 g / cm ³ or more, 60 to 85% by weight and (c1) MFR of 1.0 to 10.0 g / 10 min, and (c2) density of 0.860 to 0.910 g / cm ³ and (c3) an ethylene-α-olefin copolymer (C) having a molecular weight distribution (Mw / Mn) of 1.0 to 3.5 and 15 to 40% by weight. The characteristic polyethylene resin material (A) for non-crosslinked electric wires is provided.

  According to a third invention of the present invention, in the second invention, the ethylene-α-olefin copolymer (C) is polymerized using a single site catalyst, and is non-crosslinked. A polyethylene resin material (A) for electric wires is provided.

  According to a fourth invention of the present invention, in the third invention, the ethylene-α-olefin copolymer (C) is produced by a high-pressure ion polymerization method. A polyethylene resin material (A) is provided.

  According to a fifth invention of the present invention, in any one of the second to fourth inventions, the high-density polyethylene (B) is multi-stage polymerized using an ion polymerization catalyst, and is non-crosslinked A polyethylene resin material (A) for electric wires is provided.

  According to a sixth invention of the present invention, in the fifth invention, there is provided a polyethylene resin material (A) for non-crosslinked electric wires, wherein the ion polymerization catalyst is a Ziegler catalyst or a single site catalyst. Is done.

  According to a seventh aspect of the present invention, there is provided an electric wire or cable characterized in that the polyethylene resin material (A) for non-crosslinked electric wires according to any one of the first to sixth aspects is used as an insulator. The

The non-crosslinked electric wire cable made of the polyethylene resin material of the present invention has a specific MFR and density range, a specific elution amount by a specific CFC is in a specific range, and a specific medium density having a relatively high crystallinity. In addition, by using a resin material containing high-density polyethylene as an insulator, the heat resistance is improved and the durability at the time of stress generation is greatly improved.
In addition, since the fluidity of the insulating layer is almost the same as that of the initial material, the insulator can be recycled when disposed as a removed cable. Therefore, at present, cables that are crosslinked and in many cases have to be incinerated or disposed of in landfills are reused, and it is expected that the environmental load will be greatly reduced.
Moreover, since it has a moderate softness | flexibility and abrasion resistance improves, it has the advantage that the same workability as the present is maintained.

The present invention is for non-crosslinked electric wires having an MFR of 0.15 to 5.0 g / 10 min, a density of 0.925 to 0.945 g / cm ³ , and a specific elution amount by CFC in a specific range. This relates to the polyethylene resin material (A). Hereinafter, the polyethylene resin material (A) for non-crosslinked electric wires and cables of the present invention will be described in detail for each item.

I. Polyethylene resin material for non-cross-linked wires and cables (A)
1. Polyethylene resin material (A)
The polyethylene resin material (A) for a non-crosslinked electric wire / cable of the present invention is a non-crosslinked electric wire made of a polyethylene resin (A1) or a polyethylene resin composition (A2) that satisfies at least the following requirements (a1) to (a3): Polyethylene resin material.
The polyethylene resins (A1) and (A2) are copolymers of ethylene and α-olefin by an ion polymerization catalyst such as a Ziegler catalyst, a Phillips catalyst, a single site catalyst (including a metallocene catalyst), It includes a blend composition of high-density polyethylene and a specific ethylene / α-olefin copolymer, and a polymer obtained by a multistage polymerization method such as two-stage polymerization or three-stage polymerization.

[Polyethylene resin material for non-cross-linked wires and cables (A)]
(A1) Melt flow rate (MFR) measured under condition D (temperature 190 ° C., load 21.18 N) based on the test method of JIS K6922-1 (1997) is 0.15 to 5.0 g / 10 min. ,
(A2) The density measured based on the test method of JIS K6922-1 (1997) is 0.925 to 0.945 g / cm ³ ,
(A3) Satisfy the following requirements (i) to (iii) measured by a cross-fractionation chromatograph (CFC).
(I) Elution amount of 40 ° C. or lower: 5 to 50% by weight
(Ii) Amount of components having a log molecular weight of 5.5 or more that elutes at 94 ° C. or less: greater than 0.1 and 5% by weight or less (iii) Amount of elution at 96 ° C. or less: 95% by weight or less

(A1) Melt flow rate (MFR):
The melt flow rate (MFR) of the polyethylene resin material (A) of the present invention is based on the test method of JIS K6922-1 (1997) under the condition D (temperature 190 ° C., load 21.18 N (2.16 kg)). The measured melt flow rate (MFR) is 0.15 to 5.0 g / 10 min, preferably 0.2 to 2.0 g / 10 min, more preferably 0.3 to 1.5 g / 10 min. is there. When the MFR is less than 0.15 g / 10 min, melt fracture is likely to occur during the coating of the electric wire, and the motor load increases and extrusion may not be possible. On the other hand, if the MFR is larger than 5.0 g / 10 min, drawdown is likely to occur, the roundness of the molded product is impaired, and characteristics such as extremely good mechanical properties and product properties may be impaired. Occurs.
In general, the MFR can be adjusted by the concentration ratio of hydrogen and ethylene introduced as a molecular weight regulator when ethylene and another α-olefin are polymerized. In the case of multi-stage polymerization or a mixture, the mixing ratio of each component is appropriately adjusted and controlled, and a slight MFR is adjusted depending on temperature conditions.

(A2) Density:
The density of the polyethylene-based resin material (A) of the present invention is 0.925 to 0.945 g / cm ³ , preferably 0.928 to 0.005 as measured based on the test method of JIS K6922-1 (1997). It indicates 940 g / cm ³ , more preferably 0.930 to 0.938 g / cm ³ . If the density is less than 0.925 g / cm ³ , the heat resistance is impaired, and the power loss during high-voltage power transmission increases. On the other hand, when the density is larger than 0.945 g / cm ³ , characteristics such as good flexibility, impact strength, transparency, and ESCR are impaired.
In general, the density can be adjusted by a concentration ratio of ethylene and another α-olefin when ethylene and the other α-olefin are polymerized. In the case of multistage polymerization or a mixture, the mixing ratio of each component is appropriately adjusted and controlled.

(A3) Elution amount of cross fraction chromatograph (CFC):
The cross-fractionation chromatograph (CFC) of the polyethylene resin material (A) of the present invention is composed of a device: CFC-T102L manufactured by Dia Instruments Co., GPC column: AD-806MS manufactured by Showa Denko Co., Ltd., three connected in series. Amount: 0.5 mg / mL, solvent: orthodichlorobenzene (ODCB) containing BHT, sample concentration: 3 mg / mL, injection amount: 0.4 mL, crystallization rate: 10 ° C./hour, solvent flow rate: 1 mL / min Measured at conditions.

In the present invention, it is important that the requirements by the CFC measurement satisfy the following (i) to (iii).
(I) Elution amount of 40 ° C. or lower: 5 to 50% by weight
(Ii) Amount of components having a log molecular weight of 5.5 or more that elutes at 94 ° C. or less: greater than 0.1 and 5% by weight or less (iii) Amount of elution at 96 ° C. or less: 95% by weight or less

The requirement (i) for CFC elution is that the elution amount at 40 ° C. or less satisfies 5 to 50% by weight, preferably 10 to 40% by weight, more preferably 20 to 35% by weight. When the amount of elution at 40 ° C. or less is less than 5% by weight, flexibility is impaired. On the other hand, if the elution amount of 40 ° C. or less is larger than 50% by weight, the heat resistance is impaired, and the power loss during voltage transmission increases.
In order to control these elution amounts, it is achieved by reducing the low crystalline component of the polyethylene resin material. As a method of reducing the low crystalline component, in the case of copolymerization of an ethylene-α / olefin copolymer, a low-density component or a high-density component α-olefin is catalyzed by multistage polymerization or the like. This is achieved by controlling the polymerization temperature and the like.
In addition, in the mixed composition of high-density polyethylene and ethylene-α-olefin copolymer, adjustment of the blending ratio of high-density polyethylene and ethylene-α-olefin copolymer, and especially the crystal of ethylene-α-olefin copolymer This is achieved by controlling the ingredients. For example, when a single-site catalyst is used, the composition distribution is narrower than that of an ethylene / α-olefin copolymer produced by an ion polymerization catalyst such as a conventional Ziegler catalyst, and low crystalline components should be reduced. Can do.

The requirement (ii) for the CFC elution is that the amount of a component having a log molecular weight of 5.5 or more eluting at 94 ° C. or lower is 0.1 to 5% by weight or less, preferably 0.2 to 3.5% by weight or more. Satisfies 1.0 to 3.0% by weight. If the elution amount is less than 0.1% by weight, the ESCR is impaired, and if it is greater than 5% by weight, the heat resistance is impaired, and the power loss during voltage transmission increases.
The “component having a log molecular weight of 5.5 or more” described here is a value obtained by taking the logarithm of the molecular weight calculated by CFC measurement: a high molecular weight component having a log (molecular weight) of 5.5 or more (approximately 320,000 or more (Molecular weight).
In order to control the amount of elution, a comonomer is selectively introduced into a high molecular weight component having a log molecular weight of 5.5 or more by multistage polymerization or the like.
In particular, by producing high-density polyethylene by a multistage polymerization method, a comonomer can be selectively introduced on the high molecular weight side.

The CFC elution requirement (iii) satisfies an elution amount of 96 ° C. or less of 95% by weight or less, preferably 50 to 93% by weight, more preferably 50 to 92% by weight. If the elution amount is greater than 95% by weight, the heat resistance is impaired, and the power loss during voltage transmission increases.
In order to control the amount of elution, it can be controlled by the amount of high density components by multistage polymerization of ethylene / α-olefin copolymer. In the case of blend, the density of high density polyethylene is 0.950 g / cm ^3. This is achieved by positively introducing the above components.

[Production method]
In the present invention, the production of the polyethylene-based resin material (A) is not particularly limited, but may be an ion polymerization method that is produced in the presence of an ion polymerization catalyst such as a Ziegler catalyst, a Philips catalyst, or a single site catalyst. It is preferably produced by an ion polymerization method produced in the presence of a Ziegler catalyst or a single site catalyst.
In particular, in order to satisfy the CFC elution amount conditions, a comonomer is selectively introduced to a log molecular weight of 5.5 or more of a high molecular weight component by a single-site catalyst using two kinds of catalyst species or multistage polymerization. By doing so, it can be manufactured. In particular, by a multistage polymerization method, a polymerization method such as selective introduction of a comonomer on the high molecular weight side, a catalyst, the amount of comonomer, and the like are produced using general techniques.

2. Resin composition (mixed composition)
Another embodiment of the polyethylene resin material (A) of the present invention is a resin composition (mixed composition) of high-density polyethylene (B) and a specific ethylene / α-olefin copolymer (C). .
Specifically, (b1) MFR is 0.1 to 1.0 g / 10 min, (b2) high density polyethylene (B) having a density of 0.950 g / cm ³ or more (B) 60 to 85% by weight, and (c1) Ethylene having an MFR of 1.0 to 10.0 g / 10 min, (c2) density of 0.860 to 0.910 g / cm ³ , and (c3) molecular weight distribution (Mw / Mn) of 1.0 to 3.5 The α-olefin copolymer (C) is composed of 15 to 40% by weight.

[High-density polyethylene (B)]
The high density polyethylene (B) used in the present invention is an ethylene homopolymer produced by an ion polymerization method such as a Ziegler catalyst, a Phillips catalyst or a single site catalyst, or a copolymer of ethylene and a small amount of α-olefin. A polymer including a polymer and having physical properties of (b1) MFR of 0.1 to 1.0 g / 10 min and (b2) density of 0.950 g / cm ³ or more is used.

(B1) MFR:
The high density polyethylene (B) used in the present invention has an MFR of 0.1 to 1.0 g / 10 min at 190 ° C. and a load of 2.16 kg (21.18 N), preferably 0.15 to 0.8 g / It indicates 10 minutes, more preferably 0.2 to 0.5 g / 10 minutes. When the MFR is less than 0.1 g / 10 min, melt fracture is likely to occur when the electric wire is covered. On the other hand, if the MFR is larger than 1.0 g / 10 min, drawdown is likely to occur, and the roundness of the molded product is impaired. Therefore, the content of high-density polyethylene is limited, and extremely good mechanical properties are obtained. Features such as product physical properties are impaired.

(B2) Density:
The high density polyethylene (B) used in the present invention has a density of 0.950 g / cm ³ or more, preferably 0.953 to 0.970 g / cm ³ , more preferably 0.954 to 0.965 g / cm ³ . It is shown. When the density is less than 0.950 g / cm ³ , the heat resistance is impaired, and the power loss during high-voltage power transmission increases. On the other hand, if the density is larger than 0.970 g / cm ³ , characteristics such as good flexibility, impact strength, transparency, and ESCR may be impaired. There are also concerns that cheap and economical production is difficult.

[Production method]
The production of the high-density polyethylene (B) used in the present invention is not particularly limited, but may be an ion polymerization method produced in the presence of an ion polymerization catalyst such as a Ziegler catalyst, a Phillips catalyst, or a single site catalyst. A comonomer is selectively introduced into a high molecular weight component having a log molecular weight of 5.5 or more by multistage polymerization or the like, preferably by ionic polymerization produced in the presence of a Ziegler catalyst or a single site catalyst. It is desirable to do. In particular, by producing high-density polyethylene by a multistage polymerization method, a comonomer can be selectively introduced on the high molecular weight side.

[Ion polymerization catalyst]
Examples of the Ziegler catalyst used above include a Ziegler catalyst in which olefin polymerization proceeds by a coordinated anionic polymerization mechanism. Specifically, an initial Ziegler catalyst such as a crystalline TiCl ₃ -AlEt ₂ Cl system or MgCl Examples thereof include _2- supported TiCl ₄ catalyst and vanadium-based catalyst disclosed in JP 2000-319331 A. In this case, as disclosed in JP-A-5-320256 and the like, a method in which the polar group of the monomer of the repeating unit (B) and the organoaluminum compound are complexed and copolymerized is preferable.
Examples of the Cr catalyst include a combination of stearic acid Cr or Cr (acetylacetonate) ₃ and AlCl ₃ -AlEt ₂ Cl disclosed in JP-A-61-278508 and JP-A-2-120304. Can be illustrated.

  Examples of the single site catalyst (or metallocene catalyst) include, for example, component (A) described in JP-A-6-172447: Periodic Table IVB to VIB group transition having at least one conjugated five-membered ring A catalyst system in which a metal compound and a component (B): an organoaluminum oxy compound are combined can be exemplified, and the monomer of the repeating unit (B) is copolymerized after previously contacting with an equimolar amount or more of a trialkylaluminum compound. Is preferred. As the component (B), an ionic compound or Lewis acid capable of converting the component [a] into a cation, a solid acid, or a layered silicate can be used instead of the organoaluminum oxy compound.

  As another ion polymerization catalyst suitably used for obtaining the high-density polyethylene (B) according to the present invention, at least a nitrogen atom, a phosphorus atom, an oxygen atom, or a sulfur atom is directly coordinated with at least a group IVA to XA metal. And a non-metallocene bridged compound called a so-called postmetallocene complex (an example of a compound of a group 4 metal in the periodic table is an N-N type arrangement) characterized by having a bulky substituent at the atom. Bisamide compounds having ligands and salicylaldiminato compounds having N-O type ligands Examples of compounds of Group 8-10 metals in the periodic table include biimino compounds having N-N type ligands and N- Salicylaldiminato compounds having O-type ligands, bridged nonmetallocene compounds such as Ni and Pd described in the following chemical formula (A) described in JP-T-10-513289) , It can be exemplified.

Also, JP-A-10-298216, JP-A-11-315109, JP-A-2000-336110, JP-A-2001-515930, Chem. Commun. , 2002, pages 744-745, and various nonmetallocene compounds described in JP2007-46032A, JP2007-77395A, and the like.
These ion polymerization catalysts can be used as a supported catalyst using an inorganic oxide, a polymer or the like as a carrier.

As the polymerization mode, any mode can be adopted as long as the catalyst component and each monomer come into contact efficiently. Specifically, a slurry method using an inert solvent, a solution polymerization method, a bulk method using a monomer as a solvent without substantially using an inert solvent, or a gas in which each monomer is in a gaseous state without using a liquid solvent substantially. For example, a gas phase method can be used.
The polymerization method is applied to continuous polymerization and batch polymerization. In the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, toluene or the like is used alone or as a mixture as a polymerization solvent. Furthermore, halogenated hydrocarbon solvents such as methylene chloride and chlorobenzene can also be used. An oxygen-containing solvent such as THF or water can be used as long as the polymerization activity is not significantly impaired. In addition, a chain transfer agent such as hydrogen can be used as a molecular weight modifier.

[Polymerization temperature]
The method for producing the high-density polyethylene (B) according to the present invention by an ion polymerization method is, for example, in the presence of an ion polymerization catalyst such as a Ziegler catalyst, a temperature of −50 ° C. to 300 ° C., preferably 0 to 150 ° C. More preferably, the polymerization is performed in the range of 50 to 100 ° C. If the polymerization temperature is less than the above lower limit, there is a possibility that the yield may be reduced or a stable product may not be obtained.On the other hand, if the polymerization temperature exceeds the upper limit, the reaction may not be stable and a polymer having a large molecular weight may be obtained. It becomes difficult.

[Polymerization pressure]
Further, the polymerization pressure is a method of copolymerization in a range of greater than 0 to 100 MPa, preferably in the range of 0.1 MPa to 10 MPa, more preferably in the range of 0.2 MPa to 5 MPa.
When the polymerization pressure is less than the above lower limit, sufficient reaction does not occur and ethylene polymerization does not proceed sufficiently, and when the above upper limit is exceeded, the reaction is not stable or ethylene polymerization activity increases. Too much risk arises.

  The production process of the high-density polyethylene (B) used in the present invention is not particularly limited, such as solution polymerization, slurry polymerization method, etc., but by using multistage polymerization in which a low molecular weight component and a high molecular weight component are continuously polymerized, It can be selectively added to the molecular weight component, and the ESCR can be remarkably improved.

[Ethylene-α-olefin copolymer (C)]
As the ethylene-α-olefin copolymer (C) according to the present invention, it is important to use one having the following physical properties.
(C1) MFR is 1.0-10.0 g / 10 min,
(C2) the density is 0.860-0.910 g / cm ³ ,
(C3) The molecular weight distribution (Mw / Mn) is 1.0 to 3.5.

(C1) Melt flow rate (MFR):
The MFR (190 ° C., 2.16 kg load) of the ethylene-α-olefin copolymer (C) used in the present invention is 1.0 to 10.0 g / 10 minutes, preferably 3.0 to 9.0 g / It indicates 10 minutes, more preferably 5.0 to 8.5 g / 10 minutes. When the MFR is less than 1.0 g / 10 min, melt fracture is likely to occur when the electric wire is covered. On the other hand, if the MFR is greater than 10.0 g / 10 min, drawdown is likely to occur, and the roundness of the molded product is impaired, so the content of high-density polyethylene is limited and extremely good mechanical properties. Characteristics such as product physical properties are impaired.
Control of these MFRs is essentially the same as in the production of the polyethylene resin material (A). Generally, hydrogen and ethylene introduced as molecular weight modifiers are polymerized when ethylene and other α-olefins are polymerized. It is adjusted by the concentration ratio.

(C2) Density:
The density of the ethylene-α-olefin copolymer (C) used in the present invention is 0.860 to 0.910 g / cm ³ , preferably 0.870 to 0.905 g / cm ³ , and more preferably 0.875. ˜0.900 g / cm ³ . When the density is less than 0.860 g / cm ³ , the heat resistance is impaired, and the power loss during high-voltage power transmission increases. On the other hand, if the density is larger than 0.910 g / cm ³ , characteristics such as good flexibility, impact strength, transparency, ESCR, etc. are impaired.
These density controls are adjusted essentially in the same manner as described in the production of the polyethylene resin material (A).

(C3) Weight average molecular weight / number average molecular weight (Mw / Mn):
The ethylene-α-olefin copolymer (C) used in the present invention has an Mw / Mn measured by GPC method of 1.0 to 3.5, preferably 1.5 to 3.3, more preferably 1. .7 to 3.0. When Mw / Mn is less than 1.0, the molecular weight distribution becomes extremely narrow, so that even when a small amount is added to the high-density polyethylene (B), melt fracture and drawdown are likely to occur and workability is deteriorated. On the other hand, when Mw / Mn is greater than 3.5, characteristics such as good impact strength, ESCR, and transparency are impaired.

[Production method]
The production of the ethylene-α-olefin copolymer (C) used in the present invention is not particularly limited, but in the presence of an ion polymerization catalyst such as a Ziegler catalyst, a Philips catalyst, a vanadium catalyst, a single site catalyst or the like. It is preferably produced by a high pressure ion polymerization method in the presence of a vanadium catalyst or a single site catalyst.

  As the production method (C) of the above-mentioned ethylene-α-olefin copolymer, JP-A-58-19309, JP-A-59-95292, JP-A-60-35005, JP-A-60-35006, JP-A-60-35007, JP-A-60-35008, JP-A-60-35209, JP-A-61-130314, JP-A-3-16388, European Patent Application Publication No. 420,436 , U.S. Pat. No. 5,055,438, and International Publication No. WO09 / 04257, for example, single-site catalyst, metallocene / alumoxane catalyst, or, for example, International Publication It reacts with a metallocene compound as disclosed in the specification of the publication W092 / 07123 and the like and a single site catalyst described below to stabilize the reaction. Using a catalyst consisting of a compound to be a down, and a method of copolymerizing the α- olefin of the main component of ethylene and minor component of having from 3 to 18 carbon atoms and the like.

[Single-site catalyst]
The compound that reacts with the single-site catalyst and becomes stable ions is an ionic compound or electrophilic compound formed from an ion pair of a cation and an anion, and reacts with a metallocene compound to form stable ions. Thus, a polymerization active species is formed. Among these, an ionic compound is represented by the following formula (I).
[Q] m + [Y] m- (I)
(M is an integer of 1 or more)

  Q in the formula is a cation component of an ionic compound, and examples thereof include a carbonium cation, a tropylium cation, an ammonium cation, an oxonium cation, a sulfonium cation, and a phosphonium cation, and further a metal that itself is easily reduced. And cations of organic metals and the like.

These cations are not only cations that can give protons as disclosed in JP-A-1-501950, but also cations that do not give protons.
Specific examples of these cations include triphenylcarbonium, diphenylcarbonium, cycloheptatrienium, indenium, triethylammonium, tripropylammonium, tributylammonium, N, N-dimethylammonium, dipropylammonium, dicyclohexylammonium, tri Phenylphosphonium, trimethylphosphonium, tri (dimethylphenyl) phosphonium, tri (methylphenyl) phosphonium, triphenylsulfonium, triphenyloxonium, triethyloxonium, pyrylium, silver ion, gold ion, platinum ion, palladium ion, mercury Ion, ferrocenium ion, etc. are mentioned.

  Y in the above formula is an anion component of an ionic compound, which is a component that reacts with a metallocene compound to become a stable anion, and is an organoboron compound anion, an organoaluminum compound anion, an organogallium compound anion, an organophosphorus compound Examples include anions, organic arsenic compound anions, and organic antimony compound anions. Specifically, tetraphenylboron, tetrakis (3,4,5-trifluorophenyl) boron, tetrakis (3,5-di (trifluoromethyl) Phenyl) boron, tetrakis (3,5- (t-butyl) phenyl) boron, tetrakis (pentafluorophenyl) boron, tetraphenylaluminum, tetrakis (3,4,5-trifluorophenyl) aluminum, tetrakis (3,5 -Di (trifluoromethyl) fur Nyl) aluminum, tetrakis (3,5-di (t-butyl) phenyl) aluminum, tetrakis (pentafluorophenyl) aluminum, tetraphenylgallium, tetrakis (3,4,5-trifluorophenyl) gallium, tetrakis (3 5-di (trifluoromethyl) phenyl) gallium, tetrakis (3,5-di (t-butyl) phenyl) gallium, tetrakis (pentafluorophenyl) gallium, tetraphenylphosphorus, tetrakis (pentafluorophenyl) phosphorus, tetraphenyl Arsenic, tetrakis (pentafluorophenyl) arsenic, tetraphenylantimony, tetrakis (pentafluorophenyl) antimony, decaborate, undecaborate, carbadodecaborate, decachlorodecaborate, etc.

  Among the electrophilic compounds, among those known as Lewis acid compounds, they react with metallocene compounds to form stable ions to form polymerization active species, and various metal halide compounds and solid acids. And metal oxides known as. Specific examples include magnesium halides and Lewis acidic inorganic compounds.

[Α-olefin]
The α-olefin of the ethylene-α-olefin copolymer (C) is an α-olefin having 3 to 18 carbon atoms, specifically, propylene, 1-butene, 1-pentene, 1-hexene, 1- Examples include octene, 1-heptene, 4-methyl-pentene-1,4-methyl-hexene-1,4,4-dimethylpentene-1. Among these α-olefins, an α-olefin having 4 to 12 carbon atoms, particularly preferably 3 to 50% by weight of one or more α-olefins having 6 to 10 carbon atoms and 97 to 50% by weight of ethylene is preferable. %, Preferably 8 to 45% by weight of α-olefin and 92 to 55% by weight of ethylene, more preferably 12 to 40% by weight of α-olefin and 88 to 60% by weight of ethylene.

[Copolymerization]
The copolymer is preferably produced by a high pressure ionic polymerization method. The high-pressure ion polymerization method is a method described in JP-A-56-18607 and JP-A-58-225106. Specifically, the pressure is 300 to 3000 kg / cm ² , preferably 1100 to 2000 kg / cm ² , particularly preferably 1300 to 1800 kg / cm ² , and the temperature is 125 ° C. or higher, preferably 130 to 250 ° C., particularly preferably 150. It is the manufacturing method of the ethylene-type polymer performed on reaction conditions of -200 degreeC.

[Combination ratio]
The blending ratio of the high-density polyethylene (B) and the ethylene-α-olefin copolymer (C) is 85 to 60% by weight, preferably 80 to 65% by weight, more preferably 75 to 65% by weight, for the component (B). And component (C) is 15 to 40% by weight, preferably 20 to 35% by weight, more preferably 25 to 35% by weight. When the blending ratio of the component (B) exceeds 85% by weight and the component (C) is less than 40% by weight, melt fracture and drawdown are likely to occur during wire coating molding. Moreover, heat resistance is impaired, and power loss during high-voltage power transmission increases.
On the other hand, when the blending ratio of the component (B) is less than 60% by weight and the component (C) is more than 40% by weight, characteristics such as very good mechanical properties and product properties are not exhibited. As long as the component (B) and the component (C) satisfy the above ranges, each component may contain two or more types.

[Additives (optional ingredients)]
Various additives can be added to the polyethylene resin material (A) of the present invention as long as the effects of the invention are not impaired. Auxiliary additive components generally used for resin compositions, for example, antioxidants, heat stabilizers, antiblocking agents, slip agents, UV absorbers, neutralizers, antistatic agents, peroxides and other molecular weight modifiers , A coloring agent, a clearing nucleating agent, a filler, a foaming agent and the like may be contained.

  In addition, as a blending method of component (B) and component (C), mixing is performed by a method such as melt blending by Banbury mixer method, extrusion granulation method, dry blending by tumbler blender method, Henschel mixer method, V blender method or the like. it can.

II. Non-bridging electric wire / cable [Non-bridging electric wire cable]
The non-crosslinked electric wire cable of the present invention is not specified in any shape or structure except that the resin material of the present invention is used as an insulator and has a polyethylene resin having specific physical properties. It can be handled in exactly the same way as a cross-linked polyethylene insulated cable.
Therefore, the manufacture can also be manufactured by the same method as a conventional general power cable. Specifically, there are a method in which a semiconductive layer and an insulating layer made of the polyethylene resin material of the present invention are sequentially extruded on a conductor, or a method in which these multiple layers are formed by simultaneous extrusion.
In addition, the power cable of the present invention includes an external semiconductive layer, a reinforcing layer, a water shielding layer, an external metal shielding layer such as copper and aluminum, a corrosion protection layer made of plastic, and a submarine cable. An appropriate coating layer may be formed according to the purpose, such as an iron wire exterior of the specification.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.
In addition, the test methods, such as a physical property in a present Example, are as follows.

[I] Method for measuring physical properties (1) Density:
It measured based on the test method of JISK6922-1 (1997).

(2) Melt flow rate (MFR):
Based on the test method of JIS K6922-1 (1997), measurement was performed under condition D (temperature 190 ° C., load 21.18 N (2.16 kg)).

(3) Melting point:
In accordance with the method of JIS K7121 (1987), the melting peak temperature was measured using a DSC-7A DSC measuring apparatus manufactured by PerkinElmer.

(4) Weight average molecular weight (Mw / Mn):
Use c _o Tazu Inc. Model 150C, was measured under the following conditions to determine the weight average molecular weight.
Column: Shodex HT-G and HT-806M x 2 Solvent: 1,2,4-trichlorobenzene Temperature: 140 ° C
Flow rate: 1.0 ml / min Column calibration was performed using monodisperse polystyrene (S-7300, S-3900, S-1950, S-1460, S-1010, S-565, S-152, S-66 manufactured by Showa Denko. 0.0, S-28.5 and 0.25 mg / l solutions of S-5.05) were measured with a series of monodisperse standards with n-eicosane and n-tetracontane, and then fitted with a fourth-order polynomial. The relationship between the elution time and the logarithm of molecular weight was plotted.
The following formula was used for conversion to the molecular weight of polystyrene and polyethylene.
MPE = 0.468 × MPS

(5) Cross fractionation chromatograph (CFC):
The cross-fractionation chromatograph (CFC) is composed of a temperature rising elution fractionation (TREF) portion for performing crystalline fractionation and a gel permeation chromatography (GPC) portion for carrying out molecular weight fractionation.
The analysis using the CFC is performed as follows.
First, a polymer sample was completely dissolved in orthodichlorobenzene (ODCB) containing 0.5 mg / mL BHT at 140 ° C., and this solution was passed through a sample loop of the apparatus, and a TREF column (inert) maintained at 140 ° C. The polymer sample is crystallized by slowly cooling to a predetermined first elution temperature. After holding at 40 ° C. for 30 minutes, ODCB is passed through a TREF column, the elution components are injected into the GPC section, molecular weight separation is performed, and an infrared detector (MIRAN 1A IR detector manufactured by FOXBORO, measurement) A chromatogram is obtained with a wavelength of 3.42 μm). Meanwhile, in the TREF part, the temperature is raised to the next elution temperature, and after obtaining the chromatogram of the first elution temperature, the elution component at the second elution temperature is injected into the GPC part. Thereafter, the same operation is repeated to obtain a chromatogram of the eluted components at each elution temperature.

[Measurement condition]
Equipment: CFC-T102L manufactured by Dia Instruments
GPC column: Showa Denko AD-806MS (3 connected in series)
Solvent: ODCB
Sample concentration: 3 mg / mL
Injection volume: 0.4mL
Crystallization rate: 10 ° C./hour Solvent flow rate: 1 mL / min GPC measurement time: 34 minutes Stabilization time after GPC measurement: 5 minutes Elution temperature (° C.): 40, 70, 80, 83, 86, 88, 90, 92, 94, 96, 98, 100, 103, 110, 140

[Data analysis]
The chromatograms of the eluted components at each elution temperature obtained by the measurement are processed by a data processing program, and a standardized elution amount (proportional to the area of the chromatogram) is obtained so that the sum is 100%.
In addition, an integrated elution curve for the elution temperature is calculated. The integrated elution curve is differentiated with temperature to obtain a differential elution curve.
Moreover, molecular weight distribution is calculated | required by the following procedure from each chromatogram.
Conversion from the retention volume to the molecular weight is performed using a calibration curve prepared in advance with standard polystyrene.
The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000.

Inject 0.4 mL of a solution dissolved in ODCB (containing 0.5 mg / mL BHT) so that each is 0.5 mg / mL, and create a calibration curve.
The calibration curve uses a cubic equation obtained by approximation by the least square method.
Conversion to molecular weight uses a general-purpose calibration curve with reference to “Size Exclusion Chromatography” written by Sadao Mori (Kyoritsu Shuppan).
The following numerical value is used for the viscosity formula [η] = K × M ^α used at that time.
PS: K = 1.38 × 10 ⁻⁴ , α = 0.7
PE: K = 3.92 × 10 ⁻⁴ , α = 0.733
In the chromatogram at the first elution temperature, the peak due to BHT added to the solvent may overlap with the low molecular weight side of the elution component. In this case, the baseline is drawn as shown in FIG. Define the desired section.
When linear high-density polyethylene (US Department of Commerce National Institute of Standards and Technology, SRM1475) was measured by this method, the elution amount and average molecular weight at each temperature were as shown in Table 1. It was.

(6) Melt tension (MT):
Using Toyo Seiki Capillograph 1C, capillary length 8.00 mm, inner diameter 2.095 mm, outer diameter 9.50 mm, test temperature 190 ° C., molten resin extrusion speed 1 cm / min, take-up speed 3.9 m / min The tension of was measured.

(7) Melt fracture generation shear rate:
Using a Capillograph 1C manufactured by Toyo Seiki Co., Ltd., a capillary length of 40.0 mm, an inner diameter of 1.00 mm, an inflow angle of 90 °, an outer diameter of 9.50 mm, a test temperature of 190 ° C., extruded at a predetermined shear rate, and melt melt melt fracture The shear rate was measured to begin to develop.

(8) Bending stiffness (Olsen):
It was measured by the method of JIS K7106.

(9) ESCR:
It was measured by the method of JIS K6922-2 (1997) 4.7 Constant Strain Environmental Stress Crack Test (ESCR).

(10) Heat deformation:
It was measured by the method of JIS C3005 (1993). The test temperature was 130 ° C. and the load was 1.4 kgf.

[II] Raw materials used and production in this example The raw materials used in this example are as follows.
[Production of polyethylene resin material (A)]
1. Catalyst Preparation of High Density Polyethylene (B) (Component B) The catalyst was prepared by mixing 115 g of Mg (OEt) ₂ , 151 g of Ti (OBU) ₃ Cl and 37 g of n-C ₄ H ₉ OH at 150 ° C. The mixture was mixed for time to homogenize, and after cooling, a predetermined amount of normal hexane was added to make a uniform solution. Next, 457 g of diethylaluminum monochloride (DCAC) was added dropwise at a predetermined temperature and stirred for 1 hour. Furthermore, the battlefield was repeated with normal hexane to obtain 220 g of a solid catalyst.

2. Polymerization of high-density polyethylene (B) (component B) A 24 L autoclave with induction stirring was charged with 10 L of normal hexane as a polymerization solvent, 100 mg of the above solid catalyst and 15 mg of the promoter shown in Table 2, and two-stage slurry polymerization was performed. As the first stage polymerization, ethylene homopolymerization was performed at 88 ° C. for 1 hour, and as the second stage polymerization, ethylene and 1-butene were copolymerized at 65 ° C. for 1 hour. The fraction (%) indicates the weight ratio of each stage polymer in the ethylene copolymer.
After completion of the reaction, high density polyethylene (HD-1) having an MFR of 0.15 g / 10 min and a density of 0.957 g / cm ³ was obtained. Similarly, other high density polyethylenes (HD-2 to HD-5) were produced.
Table 2 shows the polymerization conditions.

3. Catalyst Preparation of Ethylene-α-Olefin Copolymer (C) (Component C) The catalyst was prepared by the method described in JP 7-508545 A. That is, to the complex dimethylsilylene bis (4,5,6,7-tetrahydroindenyl) hafnium dimethyl 2.0 mmol, tripentafluorophenyl boron was added in an equimolar amount to the above complex, and diluted to 10 liters with toluene. Thus, a catalyst solution was prepared.

4). Polymerization of ethylene-α-olefin copolymer (C) (component C) A stirred autoclave type continuous reactor having an internal volume of 1.5 liters was maintained at a pressure of 130 MPa, and a mixture of ethylene and 1-hexene. Was continuously fed at a rate of 40 kg / h so that the composition of 1-hexene was 74% by weight. Further, the catalyst supply amount was adjusted so that the polymerization temperature was maintained at 135 ° C. The polymer production per hour was about 3.3 kg.
After completion of the reaction, an ethylene / 1-hexene copolymer (PE-1) having an MFR of 8 g / 10 min, a density of 0.880 g / cm ³ , and Mw / Mn of 2.3 was obtained.

[Example 1]
Production of polyethylene resin material (A) pellets:
HD-1 was used as Component B and PE-1 was used as Component C, and the mixture was uniformly mixed so that the weight ratio of B to C was 70:30. Irganox 1076 (manufactured by Ciba Geigy) and P-EPQ (manufactured by Sand) are blended with 100 parts by weight of the mixture and melt mixed at a cylinder temperature of 190 ° C. using a 30 mmφ single screw extruder. After granulation, polyethylene resin material (A) pellets composed of component B and component C were obtained.
The obtained polyethylene resin material (A) has an MFR of 0.5 g / 10 min, a density of 0.934 g / cm 3, a melting point of 132 ° C., and analyzed by a cross fractionation chromatograph (CFC). 32%, (2) 1.8% of the component having a log molecular weight of 5.5 or more eluted at 94 ° C. or lower, and (3) 90% of the eluted amount of 96 ° C. or lower.
The results of the obtained CFC data of Example 1 are shown in Table 3 and FIG.

When the melt tension and shear rate were measured using the polyethylene resin material (A), the melt tension was 4.9 cN, the melt fracture generation shear rate was 1000 cm ⁻¹ or more, and good extrusion in the production of electric cables and cables. And surface properties.
Further, the polyethylene resin material (A) pellet was melted at 180 ° C., pressed, cooled, a sheet having a predetermined thickness was prepared, and the physical properties were measured.
The bending stiffness was 430 MPa, the ESCR was not cracked at 1000 hr, the heat deformation was as low as 2.5%, and a material having flexibility and heat resistance and durability was obtained.
In addition, as an evaluation of recyclability using polyethylene resin material (A) pellets, assuming a wire coating process, the MFR of the sample was re-kneaded 5 times at a cylinder temperature of 190 ° C. using a 30 mmφ single screw extruder. As a result of evaluating the decrease, the MFR of the sample was 0.13 g / 10 min. Even after the cable was collected, it could be reused after being pulverized and pelletized. The results are shown in Table 4.

[Example 2]
As the polyethylene resin material (A), a resin material obtained by blending 80% by weight of the high-density polyethylene of the component (B) of Example 1 and 20% by weight of the ethylene-α-olefin copolymer of the component (C) was used. Were evaluated in the same manner as in Example 1.
As in Example 1, all the performances were good. The results are shown in Table 4.

[Comparative Example 1]
Evaluation of physical properties of linear low-density polyethylene (MFR 0.7 g / 10 min, density 0.923 g / cm ³ , melting point 119 ° C., brand: UE320 made by Nippon Polyethylene) currently used for electric cables did. The results are shown in Table 4.
The resin has a melt tension of 6 cN and a melt fracture generation region of 1000 cm ⁻¹ or more, and has excellent extrudability and surface characteristics in the production of electric cables.
The physical properties of the press test piece were 230 MPa, the ESCR was not cracked at 1000 hr, and the flexibility and durability were good. However, under the heat deformation measurement conditions, it melted and could not be measured.

[Comparative Example 2]
Moreover, the silane cross-linked power cable provided with the heat resistance of the above-mentioned linear low density polyethylene (MFR 0.7 g / 10 min, density 0.923 g / cm ³ , melting point 119 ° C., brand: UE320 manufactured by Nippon Polyethylene Co., Ltd.) is recovered. However, after pulverization, an attempt was made to evaluate the recyclability, but it could not be melted and reused. The results are shown in Table 4.

[Comparative Examples 3 to 8]
Tables 5 and 6 show the measurement results of the compositions produced by changing the type of the resin of Component B, the blending amounts of Component B and Component C, and the like based on Example 1.
In Comparative Example 8, commercially available high-density polyethylene (MFR: 0.5 g / 10 min, density 0.961 g / cm ³ , brand: KL285A, manufactured by Nippon Polyethylene Co., Ltd.) was used as Component B.

From the evaluation results of Tables 4 to 6, in Comparative Example 3, the density of the polyethylene resin material (A) and the requirement (i) of the CFC are removed by deviating the mixing ratio of the component (B) and the component (C). Melt tension, fluidity, bending stiffness, heat deformation (heat resistance) and the like were all inferior.
In Comparative Example 4, in the production of the high-density polyethylene of component (B), no comonomer is used during the second stage polymerization, and the CFC requirement (ii) of the polyethylene resin material (A) is eluted at 94 ° C. or lower. The amount of components having a log molecular weight of 5.5 or more was as small as 0.09% by weight, and the ESCR was inferior.
In Comparative Example 5, in the production of the high-density polyethylene of component (B), a large amount of comonomer is used during the second stage polymerization, and the requirement (iii) of CFC increases to 97% by weight, Melt fracture occurred and the fluidity was poor. In the heat deformation test, some melting occurred.
In Comparative Example 6, since the high-density polyethylene of component (B) is a homopolymer product, the CFC requirement (ii) of the polyethylene resin material (A) is not satisfied, melt fracture occurs, and fluidity is inferior. It was a thing.
In Comparative Example 7, the MFR of the polyethylene resin material (A) was small, outside the scope of the present invention, melt fracture occurred, and fluidity was poor.
In Comparative Example 8, when commercially available high-density polyethylene was used as the component (B), the CFC requirement (ii) of the polyethylene resin material (A) was not satisfied, and the ESCR was inferior.

  The non-crosslinked electric wire cable made of the polyethylene resin material of the present invention has improved heat resistance and greatly improved durability at the time of stress generation, so there is no need to go through a crosslinking step when manufacturing the cable. Since the fluidity is almost the same as that of the initial material, when it is disposed as a removal cable, the insulator can be recycled, so that the industrial applicability is high.

It is a figure of the description of the base line of a chromatogram in GPC, and an area. It is a figure which shows the result of the CFC data of Example 1.

Claims (7)

A polyethylene resin material (A) for non-crosslinked electric wires, which satisfies at least the following requirements (a1) to (a3).
(A1) Melt flow rate (MFR) measured under condition D (temperature 190 ° C., load 21.18 N) based on the test method of JIS K6922-1 (1997) is 0.15 to 5.0 g / 10 min. ,
(A2) The density measured based on the test method of JIS K6922-1 (1997) is 0.925 to 0.945 g / cm ³ ,
(A3) Satisfy the following requirements (i) to (iii) measured by a cross-fractionation chromatograph (CFC).
(I) Elution amount of 40 ° C. or lower: 5 to 50% by weight
(Ii) Amount of components having a log molecular weight of 5.5 or more that elutes at 94 ° C. or less: greater than 0.1 and 5% by weight or less (iii) Amount of elution at 96 ° C. or less: 95% by weight or less The polyethylene resin material (A) for non-crosslinked electric wires is (b1) high density polyethylene (B) having an MFR of 0.1 to 1.0 g / 10 min and (b2) a density of 0.950 g / cm ³ or more. 60-85 wt% and (c1) MFR is 1.0 to 10.0 g / 10 min, (c2) a density of 0.860~0.910g / cm ^3, (c3) a molecular weight distribution (Mw / The polyethylene resin material for non-crosslinked electric wires according to claim 1, comprising 15 to 40% by weight of an ethylene-α-olefin copolymer (C) having a Mn) of 1.0 to 3.5. A).   The polyethylene resin material (A) for non-crosslinked electric wires according to claim 2, wherein the ethylene-α-olefin copolymer (C) is polymerized using a single site catalyst.   The polyethylene resin material (A) for non-crosslinked electric wires according to claim 3, wherein the ethylene-α-olefin copolymer (C) is produced by a high-pressure ion polymerization method.   The polyethylene resin material (A) for non-crosslinked electric wires according to any one of claims 2 to 4, wherein the high density polyethylene (B) is multi-stage polymerized using an ion polymerization catalyst.   The polyethylene resin material (A) for non-crosslinked electric wires according to claim 5, wherein the ion polymerization catalyst is a Ziegler catalyst or a single site catalyst.   An electric wire or cable using the polyethylene resin material (A) for non-crosslinked electric wires according to any one of claims 1 to 6 as at least an insulator.

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