JP5163237B2 - Resin composition for electric wire coating or sheath, electric wire and cable - Google Patents

Description

  The present invention relates to a resin composition for covering an electric wire or a sheath, an electric wire and a cable.

  Resin compositions containing high-density polyethylene and low-density polyethylene are used for covering electric wires. For example, Patent Document 1 describes a blend polymer composition containing at least high-density polyethylene and low-density polyethylene. Patent Document 2 discloses a density, MFR, and fish eye obtained by copolymerizing ethylene and α-olefin by gas phase polymerization in the presence of a chromium-containing catalyst as a resin composition for wire coating or insulation. A composition of linear low density polyethylene with a number in a specific range and a polyolefin resin is described.

JP 2004-71250 A JP 2006-111668 A

However, the above resin composition is not sufficiently satisfactory in terms of kneading load or heat deformation.
Under such circumstances, the problem to be solved by the present invention is a resin composition containing an ethylene-α-olefin copolymer, which has a low kneading load during molding and is heated when formed into a molded body. An object of the present invention is to provide a resin composition for covering an electric wire or a sheath with small deformation.

That is, the first of the present invention is a resin composition for wire coating or sheath containing an ethylene-α-olefin copolymer, and for wire coating satisfying all of the following requirements (a1) to (a5). Or it is a thing concerning the resin composition for sheaths.
(A1) Melt flow rate (MFR (2.16)) is 0.2-2 g / 10 minutes (a2) Density is 920-940 kg / m ³
(A3) Melting component ratio (HL110) of 110 ° C. or lower is 30 to 75%
(A4) Flow activation energy (Ea) is 40 kJ / mol or more (a5) Molecular weight distribution (Mw / Mn) is 6 to 25

A second aspect of the present invention relates to an electric wire in which a conductor is coated with the resin composition.
A third aspect of the present invention is a cable in which an electric wire bundle in which a plurality of electric wires whose conductors are covered with a resin or a resin composition is bundled is covered with a sheath made of the resin composition. It depends on.

The resin composition containing the ethylene-α-olefin copolymer of the present invention has a low kneading load at the time of molding and a small heat deformation when formed into a molded body, and is suitably used for wire coating or sheathing. It is a resin composition.
The electric wire of the present invention has a low kneading load of the resin composition when the conductor is coated with a melt-kneaded resin composition, and the obtained electric wire is small in heat deformation.
When the cable of the present invention is produced by coating an electric wire with a resin composition obtained by melt-kneading, the load of kneading of the resin composition is low, and the resulting cable is small in heat deformation.

The resin composition of the present invention is an electric wire coating or sheath resin composition containing an ethylene-α-olefin copolymer, and satisfies the following requirements (a1) to (a5) or This is a resin composition for a sheath.
(A1) Melt flow rate (MFR (2.16)) is 0.2-2 g / 10 minutes (a2) Density is 920-940 kg / m ³
(A3) Melting component ratio (HL110) of 110 ° C. or lower is 30 to 75%
(A4) Flow activation energy (Ea) is 40 kJ / mol or more (a5) Molecular weight distribution (Mw / Mn) is 6 to 25
The melt flow rate (MFR) of the resin composition of the present invention is 0.2 to 2 g / 10 min (requirement (a1)). From the viewpoint of improving the impact strength of the electric wire or cable coated with the resin composition, the MFR is preferably 1.5 g / 10 min or less, more preferably 1 g / 10 min or less. Further, from the viewpoint of reducing the kneading load of the resin composition when the conductor or electric wire is coated with the melt-kneaded resin composition, the MFR is preferably 0.3 g / 10 min or more, more preferably 0.4 g / 10 min or more. The MFR is measured under the conditions of a load of 21.18 N and a temperature of 190 ° C. in the method defined in JIS K7210-1995.

The density of the resin composition of the present invention is 920 to 940 kg / m ³ (requirement (a2)). From the viewpoint of improving the flexibility of the electric wire or cable coated with the resin composition, the density of the resin composition is preferably 935 kg / m ³ or less, more preferably 930 kg / m ³ or less. Further, from the viewpoint of smaller heat deformation of the wire or cable coated with the resin composition, the density of the resin composition is preferably not 920 kg / m ³ or more, more preferably 926kg / m ³ or more is there. The density is measured according to a method defined in Method A of JIS K7112-1980 using a test piece subjected to annealing described in JIS K6760-1995.

  The ratio of heat of fusion at 110 ° C. or lower (HL110) of the resin composition of the present invention is 30 to 75% (requirement (a3)). From the viewpoint of further reducing the heat deformation of the electric wire or cable covered with the resin composition, the HL110 of the resin composition is preferably 72% or less, more preferably 70% or less. From the viewpoint of improving the impact strength of the electric wire or cable coated with the resin composition, the HL110 of the resin composition is preferably 40% or more, more preferably 50% or more. The heat of fusion rate of 110 ° C. or lower (HL110) is measured using DSC, and is expressed as a value obtained by dividing the heat of fusion due to the component melting at 110 ° C. or lower by the total heat of fusion.

  The flow activation energy (Ea) of the resin composition of the present invention is 40 kJ / mol or more (requirement (a4)). From the viewpoint of reducing the kneading load of the resin composition when the conductor or electric wire is coated with the melt-kneaded resin composition, Ea of the resin composition is preferably 45 kJ / mol or more, more preferably 50 kJ / mol. It is more than mol, More preferably, it is more than 60 kJ / mol. Further, from the viewpoint of increasing the impact strength of the electric wire or cable coated with the resin composition, the Ea of the resin composition is preferably 100 kJ / mol or less, more preferably 90 kJ / mol or less. The method for obtaining Ea will be described later.

  The resin composition of the present invention has a molecular weight distribution (Mw / Mn) of 6 to 25 (requirement (a5)). Mw / Mn of the resin composition is preferably 7 or more, more preferably 8 or more, from the viewpoint of reducing the kneading load of the resin composition when the conductor or electric wire is coated with the melt-kneaded resin composition. More preferably, it is 9 or more. Further, from the viewpoint of increasing the impact strength of the electric wire or cable coated with the resin composition, the Mw / Mn of the resin composition is preferably 20 or less, more preferably 17 or less. The value of the molecular weight distribution (Mw / Mn) is determined from the molecular weight distribution curve obtained by gel permeation chromatography method and the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene. , Mw is divided by Mn.

  The resin composition of the present invention preferably contains an ethylene-α-olefin copolymer (I) and high-density polyethylene (II).

  The ethylene-α-olefin copolymer (I) in the present invention is an ethylene-α-olefin copolymer obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms. Examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4 -Methyl-1-pentene, 4-methyl-1-hexene and the like can be mentioned, and 1-butene, 1-hexene and 1-octene are preferable. Moreover, said C3-C20 alpha olefin may be used independently and may use 2 or more types together.

  Examples of the ethylene-α-olefin copolymer (I) include an ethylene-propylene copolymer, an ethylene-1-butene copolymer, an ethylene-1-hexene copolymer, an ethylene-1-octene copolymer, And ethylene-1-butene-1-hexene copolymer, and the like, preferably ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene-1- They are a butene-1-hexene copolymer and an ethylene-1-butene-1-octene copolymer.

  The content of the monomer unit based on ethylene in the ethylene-α-olefin copolymer (I) is usually 50 to 99% by weight, with the total weight of the ethylene-α-olefin copolymer being 100% by weight. . The content of the monomer unit based on the α-olefin is usually 1 to 50% by weight, where the total weight of the ethylene-α-olefin copolymer is 100% by weight.

  The melt flow rate (MFR) of the ethylene-α-olefin copolymer (I) is preferably 0.05 to 2 g / 10 minutes (requirement (b1)). From the viewpoint of improving the impact strength of the electric wire or cable coated with the resin composition, the MFR of the ethylene-α-olefin copolymer (I) is more preferably 1.5 g / 10 min or less, and still more preferably. 1 g / 10 min or less. Further, from the viewpoint of reducing the kneading load of the resin composition when the conductor or electric wire is coated with the melt-kneaded resin composition, the MFR of the ethylene-α-olefin copolymer (I) is more preferably 0. 0.1 g / 10 min or more, more preferably 0.15 g / 10 min or more. The MFR is measured under the conditions of a load of 21.18 N and a temperature of 190 ° C. in the method defined in JIS K7210-1995.

The density of the ethylene-α-olefin copolymer (I) is preferably 905 to 935 kg / m ³ (requirement (b2)). From the viewpoint of improving the flexibility of the electric wire or cable coated with the resin composition, the density of the ethylene-α-olefin copolymer (I) is more preferably 930 kg / m ³ or less, and further preferably 925 kg. / M ³ or less. Further, from the viewpoint of further reducing the heat deformation of the electric wire or cable coated with the resin composition, the density of the ethylene-α-olefin copolymer (I) is more preferably 910 kg / m ³ or more, and further preferably. Is 915 kg / m ³ or more. The density is measured according to a method defined in Method A of JIS K7112-1980 using a test piece subjected to annealing described in JIS K6760-1995.

  The ethylene-α-olefin copolymer (I) is an ethylene-α-olefin copolymer having a long chain branch, and the flow activation energy (Ea) of such an ethylene-α-olefin copolymer. ) Is preferably 40 kJ / mol or more (requirement (b3)). From the viewpoint of reducing the kneading load of the resin composition when the conductor or electric wire is coated with a melt-kneaded resin composition, the Ea of the ethylene-α-olefin copolymer (I) is more preferably 50 kJ / mol. It is above, More preferably, it is 60 kJ / mol or more. From the viewpoint of increasing the impact strength of the electric wire or cable coated with the resin composition, the ethylene-α-olefin copolymer (I) Ea is more preferably 100 kJ / mol or less, and still more preferably 90 kJ / mol. It is as follows.

The flow activation energy (Ea) is a master curve showing the dependence of the melt complex viscosity (unit: Pa · sec) at 190 ° C. on the angular frequency (unit: rad / sec) based on the temperature-time superposition principle. Is a numerical value calculated by the Arrhenius equation from the shift factor (a _T ) at the time of creating the value, and is a value obtained by the following method. That is, an ethylene-α-olefin copolymer at each temperature (T, unit: ° C.) for four temperatures including 190 ° C. among temperatures of 130 ° C., 150 ° C., 170 ° C., 190 ° C., and 210 ° C. The melt complex viscosity-angular frequency curve (melt melt viscosity unit is Pa · sec, angular frequency unit is rad / sec) based on the temperature-time superposition principle at each temperature (T). For each melt complex viscosity-angular frequency curve, the shift factor (a _T ) at each temperature (T) obtained when superimposed on the melt complex viscosity-angular frequency curve of the ethylene copolymer at 190 ° C. is obtained. , and each of the temperature (T), a first-order approximation of from shift factor and (a _T), by the method of least squares and [ln (a _T)] and [1 / (T + 273.16) ] at each temperature (T) Formula (Formula (I) below) is calculated. Next, Ea is obtained from the slope m of the linear expression and the following expression (II).
ln (aT) = m (1 / (T + 273.16)) + n (I)
Ea = | 0.008314 × m | (II)
a _T : Shift factor Ea: Activation energy of flow (unit: kJ / mol)
T: Temperature (unit: ° C)
For the calculation, commercially available calculation software may be used. As the calculation software, Rheos V. manufactured by Rheometrics is used. 4.4.4.
The shift factor (a _T ) is obtained by moving the logarithmic curve of the melt complex viscosity-angular frequency at each temperature (T) in the log (Y) = − log (X) axis direction (however, the Y axis Is the complex viscosity of the melt, and the X axis is the angular frequency.), And the amount of movement when superposed on the melt complex viscosity-angular frequency curve at 190 ° C., in the superposition, melting at each temperature (T) The logarithmic curve of complex viscosity-angular frequency moves the angular frequency aT times and the melt complex viscosity 1 / aT times.
In addition, when obtaining the linear approximation formula (I) obtained from the shift factors and temperatures at four temperatures including 190 ° C. from 130 ° C., 150 ° C., 170 ° C., 190 ° C., and 210 ° C. by the method of least squares. The correlation coefficient is usually 0.99 or more.

  The above-mentioned melt complex viscosity-angular frequency curve is measured using a viscoelasticity measuring apparatus (for example, Rheometrics Mechanical Spectrometer RMS-800 manufactured by Rheometrics). Usually, geometry: parallel plate, plate diameter: 25 mm, plate interval: It is performed under the conditions of 1.5 to 2 mm, strain: 5%, angular frequency: 0.1 to 100 rad / sec. The measurement is performed in a nitrogen atmosphere, and it is preferable that an appropriate amount of an antioxidant (for example, 1000 ppm) is blended in advance with the measurement sample.

  The molecular weight distribution (Mw / Mn) of the ethylene-α-olefin copolymer (I) is preferably 6 to 25 (requirement (b4)). Mw / Mn of the ethylene-α-olefin copolymer (I) is more preferably from the viewpoint of lowering the kneading load of the resin composition when the conductor or electric wire is coated with the melt-kneaded resin composition. It is 7 or more, more preferably 8 or more, and most preferably 9 or more. Further, from the viewpoint of increasing the impact strength of the electric wire or cable coated with the resin composition, the Mw / Mn of the ethylene-α-olefin copolymer (I) is more preferably 20 or less, and even more preferably 17 or less. It is. The value of the molecular weight distribution (Mw / Mn) is determined from the molecular weight distribution curve obtained by gel permeation chromatography method and the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene. , Mw is divided by Mn.

  Examples of the method for producing the ethylene-α-olefin copolymer (I) include solid particles obtained by supporting a promoter compound such as an organoaluminum compound, an organoaluminum oxy compound, a boron compound, and an organozinc compound on a particulate compound. And a ligand having a structure in which two cyclopentadienyl type anion skeletons are bonded to each other by a cross-linking group such as an alkylene group or a silylene group. Examples thereof include a method in which ethylene and an α-olefin are copolymerized in the presence of a polymerization catalyst using a transition metal compound (hereinafter referred to as component (b)) as a catalyst component.

  Examples of the component (a) include a component in which methylalumoxane is mixed with porous silica, a component in which diethyl zinc, water, and fluorinated phenol are mixed with porous silica.

More specific examples of component (a) include component (a) diethylzinc, component (b) fluorinated phenol, component (c) water, component (d) porous silica and component (e) 1,1,1, Examples include a promoter component (hereinafter referred to as component (I) -2) obtained by contacting 3,3,3-hexamethyldisilazane (((CH ₃ ) ₃ Si) ₂ NH).

  Examples of the fluorinated phenol of component (b) include pentafluorophenol, 3,5-difluorophenol, 3,4,5-trifluorophenol, 2,4,6-trifluorophenol and the like. From the viewpoint of increasing the flow activation energy (Ea) and molecular weight distribution (Mw / Mn) of the ethylene-α-olefin copolymer of the present invention, it is preferable to use two types of fluorinated phenols having different numbers of fluorines. The molar ratio of phenol having a large number of fluorines to phenol having a small number of fluorines is usually 20/80 to 80/20, and a higher molar ratio of phenol having a small number of fluorines is preferred.

The amount of component (a), component (b) and component (c) used is the molar ratio of the amount of each component used: component (a): component (b): component (c) = 1: y: z Then, it is preferable that y and z satisfy the following formula.
| 2-y-2z | ≦ 1
Y in the above formula is preferably a number of 0.01 to 1.99, more preferably a number of 0.10 to 1.80, and still more preferably a number of 0.20 to 1.50. Most preferably, the number is 0.30 to 1.00.

  The amount of the component (d) used relative to the component (a) is such that the number of moles of zinc atoms contained in the particles obtained by contacting the component (a) and the component (d) is 0.00 per gram of the particles. The amount is preferably 1 mmol or more, and more preferably 0.5 to 20 mmol. The amount of the component (e) to be used with respect to the component (d) is preferably an amount that makes the component (e) 0.1 mmol or more per 1 g of the component (d), and an amount that becomes 0.5 to 20 mmol. More preferably.

  The component (b) includes a zirconocene complex in which two indenyl groups are bonded by a crosslinking group such as an ethylene group, a dimethylmethylene group, and a dimethylsilylene group; Zirconocene complex in which a methylindenyl group is bonded (bridged bisindenylzirconium complex); Zirconocene complex in which two methylcyclopentadienyl groups are bonded by a crosslinking group such as ethylene, dimethylmethylene, and dimethylsilylene; And a zirconocene complex in which two dimethylcyclopentadienyl groups are bonded by a bridging group such as a dimethylmethylene group and a dimethylsilylene group. Moreover, as a metal atom of a component (b), a zirconium and hafnium are preferable, and also as a remaining substituent which a metal atom has, a diphenoxy group and a dialkoxy group are preferable. As the component (b), from the viewpoint of increasing the flow activation energy (Ea) of the ethylene-α-olefin copolymer of the present invention, a cross-linked bisindenyl zirconium complex is preferable, and ethylene bis (1- Indenyl) zirconium diphenoxide.

  In the polymerization catalyst comprising the above component (a) and component (b), an organoaluminum compound may be used as a co-catalyst component as appropriate. Examples of the organoaluminum compound include triisobutylaluminum, trinormal Examples include octyl aluminum.

The amount of the component (b) used is preferably 5 × 10 ^{−6 to} 5 × 10 ⁻⁴ mol per 1 g of the component (b). The amount of the organoaluminum compound used is preferably such that the aluminum atom of the organoaluminum compound is 1 to 2000 mol per mol of the metal atom of the metallocene complex.

  In addition, in the polymerization catalyst comprising the above component (a) and component (b), an electron donating compound may be used as a catalyst component as appropriate. Examples of the electron donating compound include triethylamine, Examples thereof include normal octylamine.

  When two types of fluorinated phenols having different numbers of fluorine are used as the component (b) fluorinated phenol, it is preferable to use an electron donating compound.

  The amount of the electron-donating compound used is usually 0.1 to 10 mol% with respect to the number of moles of aluminum atoms in the organoaluminum compound used as the promoter component, and increases the molecular weight distribution (Mw / Mn). From the viewpoint, the amount used is preferably higher.

  More specifically, the method for producing an ethylene-α-olefin copolymer of the present invention includes the presence of a catalyst obtained by contacting the component (ii) -2, a crosslinked bisindenylzirconium complex and an organoaluminum compound. Below, the method of copolymerizing ethylene and a C3-C20 alpha olefin is mention | raise | lifted.

  The polymerization method is preferably a continuous polymerization method involving the formation of ethylene-α-olefin copolymer particles, for example, continuous gas phase polymerization, continuous slurry polymerization, continuous bulk polymerization, preferably continuous gas phase Polymerization. The gas phase polymerization reaction apparatus is usually an apparatus having a fluidized bed type reaction tank, and preferably an apparatus having a fluidized bed type reaction tank having an enlarged portion. A stirring blade may be installed in the reaction vessel.

  As a method of supplying each component of the polymerization catalyst used in the production of the ethylene-α-olefin copolymer of the present invention to the reaction vessel, usually using an inert gas such as nitrogen or argon, hydrogen, ethylene, etc., A method of supplying in a state free from moisture and a method of supplying each component in a solution or slurry after dissolving or diluting each component in a solvent are used. Each component of the polymerization catalyst may be supplied individually, or arbitrary components may be supplied in contact in advance in any order.

  Moreover, it is preferable to carry out prepolymerization before carrying out the main polymerization and to use the prepolymerized prepolymerized catalyst component as a catalyst component or catalyst for the main polymerization. In the main polymerization and the prepolymerization, the same α-olefin may be used or different α-olefins may be used. The α-olefin used for the prepolymerization is preferably an α-olefin having 4 to 12 carbon atoms, and more preferably an α-olefin having 6 to 8 carbon atoms.

  The polymerization temperature in gas phase polymerization or slurry polymerization is usually lower than the temperature at which the ethylene-α-olefin copolymer melts, preferably 0 to 150 ° C, more preferably 30 to 100 ° C, Preferably it is 50-90 degreeC. From the viewpoint of expanding the molecular weight distribution (Mw / Mn) of the ethylene-α-olefin copolymer, a higher polymerization temperature is preferable.

  The polymerization temperature in bulk polymerization is usually 150 to 300 ° C.

  The polymerization temperature in the solution polymerization is usually 150 to 300 ° C.

  The polymerization time is usually 1 to 20 hours (as an average residence time in the case of a continuous polymerization reaction). From the viewpoint of expanding the molecular weight distribution (Mw / Mn) of the ethylene-α-olefin copolymer, it is preferable that the polymerization time (average residence time) is long.

  Further, for the purpose of adjusting the melt fluidity of the copolymer, hydrogen may be added to the polymerization reaction gas as a molecular weight regulator, and an inert gas may be allowed to coexist in the polymerization reaction gas. The molar concentration of hydrogen in the polymerization reaction gas with respect to the molar concentration of ethylene in the polymerization reaction gas is usually 0.1 to 3 mol% as the molar concentration of ethylene in the polymerization reaction gas is 100 mol%. Moreover, from the viewpoint of widening the molecular weight distribution (Mw / Mn) of the ethylene-α-olefin copolymer, it is preferable that the molar concentration of hydrogen in the polymerization reaction gas is high.

  For the purpose of adjusting the density of the copolymer, the α-olefin concentration in the polymerization reaction gas can be adjusted. When the α-olefin concentration in the polymerization reaction gas is increased, the density of the obtained ethylene-α-olefin copolymer is decreased.

  The melt flow rate (MFR) of the high density polyethylene (II) in the present invention is preferably 0.2 to 20 g / 10 min (requirement (c1)). From the viewpoint of improving the impact strength of the electric wire or cable coated with the resin composition, the MFR of the high density polyethylene (II) is more preferably 10 g / 10 min or less, and further preferably 7 g / 10 min or less. . Further, from the viewpoint of reducing the kneading load of the resin composition when the conductor or electric wire is coated with the melt-kneaded resin composition, the MFR of the high-density polyethylene (II) is more preferably 0.7 g / 10 min. It is above, More preferably, it is 2 g / 10min or more. The MFR is measured under the conditions of a load of 21.18 N and a temperature of 190 ° C. in the method defined in JIS K7210-1995.

The density of the high density polyethylene (II) in the present invention is preferably 940 to 975 kg / m ³ (requirement (c2)). From the viewpoint of improving the coated wire or a flexible cable with a resin composition, density of high density polyethylene (II) is more preferably 970 kg / m ³ or less, more preferably 965 kg / m ³ or less is there. Further, from the viewpoint of reducing the heat deformation of the electric wire or cable coated with the resin composition, the density of the high-density polyethylene (II) is more preferably 950 kg / m ³ or more, and further preferably 955 kg / m ^3. That's it. The density is measured according to a method defined in Method A of JIS K7112-1980 using a test piece subjected to annealing described in JIS K6760-1995.

  As a method for producing high-density polyethylene, known olefin polymerization catalysts such as Ziegler-Natta catalysts, chromium catalysts, metallocene catalysts, solution polymerization methods, slurry polymerization methods, gas phase polymerization methods, high pressure ion polymerization methods are used. And the like, and a production method by a known polymerization method. The polymerization method may be either a batch polymerization method or a continuous polymerization method, and may be a multistage polymerization method having two or more stages.

Examples of the Ziegler-Natta catalyst include the following catalyst (1) or (2).
(1) A catalyst comprising a component in which at least one selected from the group consisting of titanium trichloride, vanadium trichloride, titanium tetrachloride and titanium haloalcolate is supported on a magnesium compound carrier, and an organometallic compound as a cocatalyst ( 2) A catalyst comprising an organometallic compound which is a coprecipitate of a magnesium compound and a titanium compound or a eutectic and a cocatalyst.

  Examples of the chromium catalyst include a catalyst composed of a component in which a chromium compound is supported on silica or silica-alumina, and an organometallic compound as a cocatalyst.

Examples of the metallocene catalyst include the following catalysts (1) to (4).
(1) A catalyst comprising a transition metal compound having a group having a cyclopentadiene skeleton and a component containing an alumoxane compound. (2) A component containing the transition metal compound, and ionic properties such as trityl borate and anilinium borate. catalyst comprising component containing a compound (3) said transition metal compound and component comprising a component containing an ionic compound, a catalyst (4) SiO ₂ the components of the consisting of components including an organic aluminum compound, Al ₂ Catalyst obtained by supporting or impregnating an inorganic particulate carrier such as O ₃ or a particulate polymer carrier such as an olefin polymer such as ethylene or styrene.

  As a method for producing high-density polyethylene, a production method using a Ziegler-Natta catalyst or a metallocene catalyst is preferred.

  The amount of the ethylene-α-olefin copolymer (I) and the high-density polyethylene (II) in the resin composition of the present invention is the sum of the ethylene-α-olefin copolymer (I) and the high-density polyethylene (II). When the content is 100 parts by weight, preferably, the content of the ethylene-α-olefin copolymer (I) is 99 to 60 parts by weight and the content of the high-density polyethylene (II) is 1 to 40 parts by weight. . From the viewpoint of reducing the heat deformation of the electric wire or cable coated with the resin composition, when the ethylene-α-olefin copolymer (I) and the high-density polyethylene (II) are combined in 100 parts by weight, the density is high. The amount of polyethylene (II) is more preferably 5 parts by weight or more, and still more preferably 10 parts by weight or more. From the viewpoint of improving the impact strength of electric wires and cables coated with the resin composition, when the ethylene-α-olefin copolymer (I) and the high-density polyethylene (II) are combined in 100 parts by weight, the high-density polyethylene The amount of (I) is more preferably 30 parts by weight or less, and still more preferably 20 parts by weight or less.

  If necessary, the resin composition of the present invention may be added with an antioxidant, an additive for crosslinking, a flame retardant, a filler, a lubricant, an antistatic agent, a weathering stabilizer, a pigment, a processability improver, a metal soap, and the like. An additive may be blended, and two or more of these additives may be used in combination.

  As the antioxidant, generally used are a phenol-based antioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant, and the like.

  Examples of phenolic antioxidants include 2,6-di-t-butyl-4-methylphenol (BHT) and n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl). Propionate (trade name Irganox 1076, manufactured by Ciba Specialty Chemicals), pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (trade name Irganox 1010, manufactured by Ciba Specialty Chemicals) 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate (trade name Irganox 3114, manufactured by Ciba Specialty Chemicals), 1,3,5-trimethyl-2,4, 6-Tris (3,5-di-tert-butyl-4-hydroxybenzine ) Benzene, 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10- And tetraoxaspiro [5,5] undecane (trade name Sumilizer GA80, manufactured by Sumitomo Chemical Co., Ltd.).

  Examples of phosphorus antioxidants include distearyl pentaerythritol diphosphite (trade name ADK STAB PEP8), tris (2,4-di-tert-butylphenyl) phosphite (trade name Irgafos 168, manufactured by Ciba Specialty Chemicals). Bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, tetrakis (2,4-di-tert-butylphenyl) 4,4′-biphenylenediphosphonite (trade name Sandostab P-EPQ , Manufactured by Clariant Shapin Co., Ltd.), bis (2-t-butyl-4-methylphenyl) pentaerythritol diphosphite, and the like.

  As an antioxidant having both a phenol structure and a phosphate structure, for example, 6- [3- (3-tert-butyl-4-hydroxy-5-methyl) propoxy] -2,4,8,10 tetra-tert- And butyl dibenz [d, f] [1,3,2] -dioxaphosphabin (trade name Sumilizer GP, manufactured by Sumitomo Chemical Co., Ltd.).

  Examples of the sulfur-based antioxidant include 4,4′-thiobis (3-methyl-6-tert-butylphenol) (trade name Sumilizer WXR, manufactured by Sumitomo Chemical Co., Ltd.), 2,2-thiobis- (4-methyl- 6-tert-butylphenol) (trade name IRGANOX 1081, manufactured by Ciba Specialty Chemical Co., Ltd.).

  Examples of other antioxidants include vitamin E and vitamin A.

  Examples of the additive for crosslinking include an alkoxysilane compound having a double bond, a compound that accelerates condensation of the alkoxysilane compound, an organic peroxide, a crosslinking aid, and the like.

  Examples of the alkoxysilane compound having a double bond include vinyl alkoxysilane compounds and acrylic alkoxysilane compounds.

  Examples of vinyl alkoxysilane compounds include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltriisopropoxysilane, allyltrimethoxysilane, vinyltris (2-methoxyethoxy) silane, vinylmethyldimethoxysilane, and the like Can be raised

  Examples of the acrylic alkoxysilane compound include 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, and the like.

  From the viewpoint of the reactivity of the condensation reaction of alkoxysilane with moisture, vinyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, allyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxy Methoxysilane such as silane is preferred, and vinyltrimethoxylane is more preferred.

  These alkoxysilane compounds may be used alone or in combination of two or more.

  An alkoxysilane compound having a double bond is grafted onto a molecule such as an ethylene-α-olefin copolymer using an organic peroxide, and the alkoxysilane compound causes a condensation reaction with moisture, thereby producing an ethylene-α- Crosslinks molecules such as olefin copolymers.

  Examples of the compound for accelerating the condensation reaction between alkoxysilane compounds include organic tin compounds, such as tin tetraacetate, butyltin triacetate, butyltin tributylate, butyltin trihexylate, butyltin trioate. Octate, butyltin trilaurate, butyltin trimethyl maleate, octyltin triacetate, octyltin tributylate, octyltin trihexylate, octyltin trioctate, octyltin trilaurate Rate, octyltin trimethyl maleate, phenyltin tributylate, phenyltin trilaurate, dibutyltin diacetate, dibutyltin dibutyrate, dibutyltin dihexylate, dibutyltin dioctate , Dibutyltin dilaurate, dibutyltin diethyl Maleate, Dioctyltin diacetate, Dioctyltin dibutyrate, Dioctyltin dihexylate, Dioctyltin dioctate, Dioctyltin dilaurate, Dioctyltin diethyl maleate, Tributyltin acetate , Tributyltin butyrate, tributyltin hexylate, tributyltin octate, tributyltin laurate, tributyltin methylmaleate, trioctyltin acetate, trioctyltin butyrate, trioctyltin hex Examples thereof include silicate, trioctyltin octate, trioctyltin laurate, and trioctyltin methyl maleate.

  Examples of organic peroxides include di-t-butyl peroxide, t-butyl hydroperoxide, t-butyl-peroxy-2-ethylhexanate, dicumyl peroxide, t-butyl peroxyisopropyl carbonate, and t-butyl. Examples thereof include peroxybenzoate, di-t-amyl peroxide, cumyl hydroperoxide, t-butyl peroxybivalate, and the like.

  Examples of the crosslinking aid include triallyl cyanurate, triallyl isocyanurate, trimethylolpropane triacrylate, trimethylolpropane ethoxytriacrylate, polyether triacrylate, glycerin propoxytriacrylate, pentaerythritol triacrylate, and the like.

  Examples of the flame retardant include metal hydroxides, metal oxides, inorganic salts / inorganic hydrated compounds, silane compounds, phosphorus compounds, bromine compounds, and chlorine compounds.

  Examples of the metal hydroxide include magnesium hydroxide, aluminum hydroxide, calcium hydroxide, zirconium hydroxide, hydrotalcite and the like.

  Examples of the metal oxide include antimony pentoxide, antimony trioxide, zinc oxide, ferrocene, copper oxide, calcium oxide, nickel oxide, bismuth oxide, zinc stannate, and calcium aluminate.

  Examples of the inorganic salt / inorganic hydrated compound include calcium carbonate, barium metaborate, kaolin clay, wax stone clay, dosonite, calcium aluminate silicate, and the like.

  Examples of the silane compound include silicon oil, silicon gum, and those in which a functional group is introduced.

  Examples of phosphorus compounds include non-halogen phosphates such as triphenyl phosphate, tricresyl phosphate, and trixylenyl phosphate; trichloroethyl phosphate, trisdichloropropyl phosphate, tris β-chloropropyl phosphate, and the like. Examples thereof include halogenated phosphoric acid ester; polyphosphoric acid ammonium; polyphosphoric acid amide; polychlorophosphate; condensed phosphonic acid ester; aromatic condensed phosphoric acid ester;

  Examples of the bromine-based compound include decabromodiphenyl oxide, hexabromochlorodecane, ethylenebistetrabromophthalimide, hexapromobenzene, and the like.

  Examples of the chlorinated compound include perchlorocyclopentadecane, chlorinated paraffin, chlorinated polyolefin, and chlorinated polyethylene.

  As the flame retardant, the above compounds may be used alone or in combination.

  The resin composition of the present invention may be a blend of resin pellets or a composition obtained by melt-kneading a resin with a known kneading apparatus such as an extruder, a roll molding machine, or a kneader.

  Since the resin composition of the present invention has a low kneading load at the time of molding and is small in heat deformation when formed into a molded body, it is suitably used for wire coating or sheathing.

The electric wire of the present invention can be obtained by covering the conductor with a molten resin composition obtained by melt-kneading the resin composition.
Moreover, the cable of the present invention can be obtained by covering an electric wire bundle in which a plurality of electric wires whose conductors are coated with a resin or a resin composition are bundled with a sheath made of the above-described resin composition of the present invention. . As the resin or resin composition for covering the above-mentioned conductor, polyethylene-based resin, ethylene-acrylic acid ester-based resin, ethylene-methacrylic acid ester-based resin, ethylene-vinyl acetate-based resin, polyvinyl chloride, Olefin rubber such as ethylene propylene rubber, chloroprene rubber, butyl rubber, nitrile rubber, silicon rubber, styrene-butadiene rubber, natural rubber, ebonite, rubber, phenol resin, polyurethane resin, epoxy resin, polyamide resin, polyimide An insulating resin such as a resin or a resin composition, or an insulating paper impregnated with an insulating oil such as mineral oil, alkylbenzene, polybutene, alkylnaphthalene, or silicone oil can be used, and the resin composition of the present invention is suitable. Used for.
The electric wires and cables of the present invention described above are difficult to be heated and deformed.

Hereinafter, the present invention will be described with reference to examples and comparative examples.
The physical properties in Examples and Comparative Examples were measured according to the following methods.

(1) Melt flow rate (MFR, unit: g / 10 minutes)
In the method defined in JIS K7210-1995, the measurement was performed under the conditions of a load of 21.18 N and a temperature of 190 ° C.

(2) Density (Unit: kg / m ³ )
It measured according to the method prescribed | regulated to A method among JISK7112-1980. The measurement sample piece was annealed according to JIS K6760-1995 and used for measurement.

(3) Flow activation energy (Ea, unit: kJ / mol)
Using a viscoelasticity measuring device (Rheometrics Mechanical Spectrometer RMS-800 manufactured by Rheometrics), a melt complex viscosity-angular frequency curve at 130 ° C., 150 ° C., 170 ° C. and 190 ° C. was measured under the following measurement conditions. From the obtained melt complex viscosity-angular frequency curve, calculation software Rhios V. The activation energy (Ea) was determined using 4.4.4.
<Measurement conditions>
Geometry: Parallel plate Plate diameter: 25mm
Plate spacing: 1.2-2mm
Strain: 5%
Angular frequency: 0.1 to 100 rad / sec Measurement atmosphere: Under nitrogen

(4) Molecular weight distribution (Mw / Mn)
Using a gel permeation chromatograph (GPC) method, molecular weight distribution curves were measured under the following conditions (1) to (8). Next, the weight average molecular weight (Mw) in terms of polystyrene and the number average molecular weight (Mn) in terms of polystyrene were determined, and the molecular weight distribution (Mw / Mn) was calculated therefrom.
(1) Apparatus: Waters 150C manufactured by Water
(2) Separation column: TOSOH TSKgelGMH-HT
(3) Measurement temperature: 145 ° C
(4) Carrier: Orthodichlorobenzene (5) Flow rate: 1.0 mL / min (6) Injection volume: 500 μL
(7) Detector: differential refraction (8) Molecular weight standard: Standard polystyrene
(TSK STANDARD POLYSTYRNE made by Tosoh)

(5) Melting component ratio of 110 ° C. or lower (HL110; unit%)
Measurement was performed using a Diamond DSC manufactured by PerkinElmer. A sample amount of 4 to 10 mg was placed in an aluminum pan and used for measurement. The temperature program was held at 150 ° C. for 5 minutes, then cooled from 150 ° C. to 20 ° C. at a temperature drop rate of 5 ° C./minute, held at 20 ° C. for 2 minutes, and then heated at a rate of 5 ° C./minute at 20 ° C. The temperature was raised to 150 ° C., and the heat of fusion at the time of temperature rise was measured. The amount of heat of fusion from the baseline connecting the temperature at which the endotherm due to melting was no longer observed and became flat and 25 ° C. was defined as the total heat of fusion (W _{total melting} ). Using the same baseline as the total heat of fusion, the heat of fusion from 25 ° C. to 110 ° C. was defined as (W ₁₁₀ ). The melting component ratio (HL110) of 110 ° C. or lower was obtained from the following formula.

_{HL110 (%) = (W 110} ) / (W _{total melting)} × 100 (%)

(6) Impact strength (unit: kJ / m ² )
The impact strength was measured as follows. The composition was pressed using a hot press at 150 ° C. to prepare a 2 mm thick sheet. About this sheet | seat, what was punched in the S-type dumbbell shape of ASTM D1822-61T was used, and the tensile impact strength was measured at 23 degreeC according to ASTMD1822-61T.

(7) Heat deformation (unit:%)
The heat deformation was measured as follows based on the heat deformation described in JIS C3005.
The composition was pressed using a 150 ° C. hot press to prepare a 1 mm thick sheet, and a 35 × 15 × 1 mm test piece was cut out. After measuring the thickness of the test piece, the test piece was placed on a round bar having a radius of 1 mm and a length of 35 mm, preheated at 120 ° C. for 30 minutes, then added with 1 kg of load and allowed to elapse for 30 minutes. Heat deformation was calculated from the following equation.
Heat deformation (%) = (Thickness before heating−Thickness after heating) / (Thickness before heating) × 100 (%)

(8) Flexibility (unit: MPa)
Flexibility was measured using an Olsen bending tester according to ASTM D747-70. A sample obtained by annealing a sheet formed to a thickness of 1 mm at 150 ° C. with a hot press in boiling water at 100 ° C. for 1 hour was used for the measurement. A smaller value indicates flexibility.

(9) Kneading load (Nm)
Using a Brabender plastic coder from Brabender, kneading was performed at 160 ° C. and 60 rpm, and the torque value after 30 minutes was measured.
A smaller value indicates a smaller kneading load.

Example 1
(1) Preparation of cocatalyst component A solid product (hereinafter referred to as solid product (a-1) was prepared in the same manner as in component (A) of Example 10 (1) and (2) of JP-A No. 2003-171415. ).) Was obtained.

(2) Preparation of prepolymerization catalyst 80 liters of butane was charged into a reactor equipped with a stirrer having an internal volume of 210 liters, which had been purged with nitrogen in advance, under normal temperature conditions. Next, 89 mmol of racemic-ethylenebis (1-indenyl) zirconium diphenoxide was added. Thereafter, the temperature in the tank was adjusted to 30 ° C., 0.1 kg of ethylene was charged, and then 0.70 kg of solid product (a-1) was charged. After the system was stabilized, 263 mmol of triisobutylaluminum was added to initiate polymerization. After the start of polymerization, the polymerization temperature in the tank was operated at 35 ° C. for 0.5 hour, then the temperature was raised to 50 ° C. over 30 minutes, and then polymerization was performed at 50 ° C. For the first 0.5 hours, ethylene is supplied at 0.7 kg / hour, and from 0.5 hours after the start of polymerization, ethylene is 4.5 kg / hour, and hydrogen is at room temperature and normal pressure at a rate of 13.5 liters / hour. And prepolymerization was carried out for a total of 4 hours. After completion of the polymerization, the reactor internal pressure was purged to 0.5 MPaG, the slurry-like prepolymerized catalyst was transferred to a dryer, and nitrogen circulation drying was performed to obtain a prepolymerized catalyst. The prepolymerization amount of the ethylene polymer in the prepolymerization catalyst was 28.3 g per 1 g of the solid product (a-1).

(3) Copolymerization of ethylene, 1-butene and 1-hexene Using the above prepolymerization catalyst, copolymerization of ethylene, 1-butene and 1-hexene was carried out in a continuous fluidized bed gas phase polymerization apparatus. The polymerization conditions were as follows: temperature 80 ° C., total pressure 2 MPa, gas linear velocity 0.4 m / s, hydrogen molar ratio to ethylene 1.2%, 1-butene molar ratio to ethylene 1.9%, ethylene 1- The molar ratio of hexene was 0.8%, and ethylene, 1-butene, 1-hexene and hydrogen were continuously fed during the polymerization in order to keep the gas composition constant. Further, the pre-polymerization catalyst and triisobutylaluminum were continuously supplied at a constant ratio so that the total powder weight of the fluidized bed was maintained at 80 kg and the average polymerization time was 3.7 hours. By polymerization, a powder of ethylene-1 butene-1-hexene copolymer (hereinafter referred to as PE-1) was obtained at a production efficiency of 21.4 kg / hr.

(4) Granulation of ethylene-1-butene-1-hexene copolymer powder Using the LCM50 extruder manufactured by Kobe Steel, the PE-1 powder obtained above was fed at a feed rate of 50 kg / hr and screw rotation. PE-1 pellets were obtained by granulation under conditions of several 450 rpm, a gate opening of 4.2 mm, a suction pressure of 0.2 MPa, and a resin temperature of 200 to 230 ° C. The results of measuring physical properties of PE-1 pellets are shown in Table 1.

(5) Preparation of resin composition 80 parts by weight of PE-1 pellets and KEIYO polyethylene G2500 (made by Keiyo polyethylene; hereinafter referred to as HD-1; physical properties of HD-1 are shown in Table 2) 20 weights as high-density polyethylene Were mixed and extruded at 200 ° C. using a single screw extruder to obtain a resin composition. Table 3 shows the physical properties of the resin composition obtained.

Example 2
A resin composition was obtained in the same manner as in Example 1 except that 85 parts by weight of PE-1 pellets and 15 parts by weight of HD-1 pellets were used. Table 3 shows the physical properties of the resin composition obtained.

Example 3
A resin composition was obtained in the same manner as in Example 1 except that 90 parts by weight of PE-1 pellets and 10 parts by weight of HD-1 pellets were used. Table 3 shows the physical properties of the resin composition obtained.

Example 4
As high-density polyethylene, it was carried out in the same manner as in Example 1 except that Hi-Zex 3300F (manufactured by Mitsui Chemicals; hereinafter referred to as HD-2; the physical properties of HD-2 are shown in Table 2) instead of HD-1 pellets was used. A resin composition was obtained. Table 3 shows the physical properties of the resin composition obtained.

Example 5
(1) Preparation of prepolymerization catalyst 80 liters of butane was charged into a reactor equipped with a stirrer with an internal volume of 210 liters, which had been purged with nitrogen in advance, under normal temperature conditions. Next, 66 mmol of racemic-ethylenebis (1-indenyl) zirconium diphenoxide was added. Thereafter, the temperature in the tank was adjusted to 35 ° C., 0.1 kg of ethylene was charged, and then 0.49 kg of the solid product (a-1) described in Example 1 was charged. After the system was stabilized, 190 mmol of triisobutylaluminum was added to initiate polymerization. After the start of polymerization, the polymerization temperature in the tank was operated at 35 ° C. for 0.5 hour, then the temperature was raised to 50 ° C. over 30 minutes, and then polymerization was performed at 50 ° C. For the first 0.5 hours, ethylene was supplied at 0.4 kg / hour, and from 0.5 hours after the start of polymerization, ethylene was 3.6 kg / hour, and hydrogen was normal temperature and normal pressure at a rate of 10.9 liters / hour. And prepolymerization was carried out for a total of 4 hours. After completion of the polymerization, the reactor internal pressure was purged to 0.5 MPaG, the slurry-like prepolymerized catalyst was transferred to a dryer, and nitrogen circulation drying was performed to obtain a prepolymerized catalyst. The prepolymerized amount of the ethylene polymer in the prepolymerized catalyst was 35.2 g per 1 g of the solid product (a-1).

(2) Copolymerization of ethylene, 1-butene and 1-hexene Using the above prepolymerization catalyst, copolymerization of ethylene, 1-butene and 1-hexene was carried out in a continuous fluidized bed gas phase polymerization apparatus. The polymerization conditions were a temperature of 85 ° C., a total pressure of 2 MPa, a gas linear velocity of 0.31 m / s, a hydrogen molar ratio to ethylene of 1.4%, a molar ratio of 1-butene to ethylene of 2.4%, and 1 to ethylene. The molar ratio of hexene was 0.7%, and ethylene, 1-butene, 1-hexene and hydrogen were continuously fed during the polymerization in order to keep the gas composition constant. Further, the total powder weight of the fluidized bed was maintained at 80 kg, and the prepolymerized catalyst and triisobutylaluminum were continuously supplied at a constant ratio so that the average polymerization time was 3.2 hours. By polymerization, a powder of ethylene-1 butene-1-hexene copolymer (hereinafter referred to as PE-2) was obtained with a production efficiency of 25.2 kg / hr.

(4) Granulation of ethylene-1-butene-1-hexene copolymer powder Using the LCM50 extruder manufactured by Kobe Steel, the PE-2 powder obtained above was fed at a feed rate of 50 kg / hr and screw rotation. PE-2 pellets were obtained by granulation under conditions of several 450 rpm, a gate opening of 4.2 mm, a suction pressure of 0.2 MPa, and a resin temperature of 200 to 230 ° C. The physical property measurement results of PE-2 pellets are shown in Table 1.

  A resin composition was obtained by the method described in Example 1 using PE-2 instead of PE-1 pellets. Table 3 shows the physical properties of the resin composition obtained.

Example 6
A resin composition was obtained by the method described in Example 4 using PE-2 instead of PE-1 pellets. Table 3 shows the physical properties of the resin composition obtained.

Example 7
A resin composition was obtained in the same manner as in Example 1 except that 55 parts by weight of PE-1 pellets and 45 parts by weight of HD-2 pellets were used. Table 3 shows the physical properties of the resin composition obtained.

Comparative Example 1
A resin composition was obtained in the same manner as in Example 4 except that 90 parts by weight of PE-1 pellets and 10 parts by weight of HD-2 pellets were used. The physical properties of the obtained resin composition are shown in Table 4.

Comparative Example 2
A resin composition was obtained in the same manner as in Example 5 except that 90 parts by weight of PE-2 pellets and 10 parts by weight of HD-1 pellets were used. The physical properties of the obtained resin composition are shown in Table 4.

Comparative Example 3
A resin composition was obtained in the same manner as in Example 6 except that 90 parts by weight of PE-2 pellets and 10 parts by weight of HD-2 pellets were used. The physical properties of the obtained resin composition are shown in Table 4.

Comparative Example 4
As the ethylene-α-olefin copolymer, pellets of NUC low-density polyethylene NUCG-7641 (manufactured by Nihon Unicar; hereinafter referred to as PE-3; the physical properties of PE-3 are shown in Table 1) were used instead of PE-1. Except for this, the same procedure as in Example 2 was performed to obtain a resin composition. The physical properties of the obtained resin composition are shown in Table 4.

Comparative Example 5
Example AFFINITY PF1140 (manufactured by Dow Chemical; hereinafter referred to as PE-4; the physical properties of PE-4 are shown in Table 1) was used as an ethylene-α-olefin copolymer instead of PE-1. 2 was performed to obtain a resin composition. The physical properties of the obtained resin composition are shown in Table 4.

Claims (3)

An ethylene-α-olefin copolymer (I) that satisfies all of the following requirements (b1) to (b4) and a high-density polyethylene (II) that satisfies the following requirements (c1) to (c2):
A resin composition for covering an electric wire or a sheath satisfying all of the following requirements (a1) to (a5) ,
The content of the ethylene-α-olefin copolymer is 99 to 60 parts by weight, and the content of the high-density polyethylene is 1 to 40 parts by weight (however, the total of the ethylene-α-olefin copolymer and the high-density polyethylene) A resin composition for covering an electric wire or a sheath .
(A1) Melt flow rate (MFR (2.16)) is 0.2-2 g / 10 min
(A2) Density is 920 to 940 kg / m ³
(A3) Melting component ratio (HL110) of 110 ° C. or lower is 30 to 75%
(A4) Flow activation energy (Ea) is 40 kJ / mol or more
(A5) Molecular weight distribution (Mw / Mn) is 6-25
Ethylene-α-olefin copolymer (I)
(B1) Melt flow rate (MFR) is 0.05-2 g / 10 min.
(B2) Density is 905 to 935 kg / m ³
(B3) Flow activation energy (Ea) is 40 kJ / mol or more
(B4) Molecular weight distribution (Mw / Mn) is 6-25
High density polyethylene (II)
(C1) Melt flow rate (MFR) is 0.2 to 20 g / 10 min.
(C2) Density is 940-975 kg / m ³   An electric wire wherein the conductor is coated with the resin composition according to claim 1.   A cable in which an electric wire bundle in which a plurality of electric wires whose conductors are covered with a resin or a resin composition is bundled is covered with a sheath made of the resin composition according to claim 1.