Oblon, Fisher, Spivak, McClelland & Maier
Ethylene copolymer
 An ethylene copolymer comprising an ethylene unit and an ester unit selected from ethylenically .alpha.,.beta.-unsaturated acid esters represented by the formula (I) or (II): ##STR1## wherein R.sup.1 represents a hydrogen atom or a methyl group; and R.sup.2 represents a halogenated alkyl group having from 1 to 15 carbon atoms; ##STR2## wherein R.sup.3 represents a hydrogen atom or a methyl group; and n represents 0 or 1, PA1 wherein said ester unit is present in a total amount of from 0.001 to 10 mol %. The copolymer has excellent dielectric breakdown characteristics, such as electricity treeing property, water treeing property, etc., and is useful as an insulating material for high-voltage cables. 
Mitsubishi Petrochemical Co., Ltd.
C C
C08F C08F
inventional inventional
Tsutomu Noriyuki Masaki Shuhei Iwao Takeo Akiyoshi
Isaka Okada Saito Doi Ishino Shimada Oonishi