Abstract: A polyethylene for an insulation layer of a power cable, of which the dissipation factor never increases even in a high-temperature, high electric field, and a crosslinked polyethylene insulated power cable which uses this polyethylene so that the high-temperature dielectric breakdown voltage is large enough for high-capacitance transmission. This polyethylene is a low-density polyethylene which is synthesized by high-pressure radical polymerization of ethylene, and has properties including: a melt flow rate of 0.1 to 10 g/10 minutes; a density of 0.915 to 0.935 g/cm.sup.3 ; an absorbance of 0.03 to 1.0 for a ketone-type carbonyl group, having a peak in a position corresponding to a wave-number of 1,725.+-.4 cm.sup.-1 in an infrared absorption spectrum, an absorbance of 1.0 or less for an ester-type carbonyl group, having a peak in a position corresponding to a wave-number of 1,743.+-.4 cm.sup.-1 and absorbances of less than 0.

Abstract: A crosslinkable polyethylene resin composition comprises, basically, (A) a copolymer of ethylene and an ethylenically unsaturated silane compound, wherein the content of the ethylenically unsaturated silane compound unit is 0.001 to 15 percent by weight, and (B) a silanol condensation. The copolymer may further comprise a monomer copolymerizable with the ethylene and the ethylenically unsaturated silane compound. The composition may be expandable, further comprising a foaming agent and may further comprise a polyolefin and a filler and may be in the form of a film or sheet.

Abstract: A conductor wire is extrusion coated with a polyethylene resin containing a copolymer comprising predominantly ethylene and an unsaturated silane compound having the formula R Si R'.sub.n Y.sub.3-n, wherein: R is an ethylenically unsaturated hydrocarbyl group or hydrocarbyloxy group; R' is an aliphatic saturated hydrocarbyl group; Y is a hydrolyzable organic group; and n is zero, 1, or 2, thereby to fabricate a coated wire which is then caused to contact water in the presence of a silanol condensation catalyst in a crosslinking process step.