| abstract |
A random copolymer is characterized in that (A) the copolymer comprises polymerized ethylene units and polymerized units of at least one cycloolefin, - (B) the mole ratio of the polymerized cycloolefin units to the polymerized ethylene units is from 3:97 to 60:40, (C) the cycloolefin is incorporated in the polymer chain without ring opening, (D) the copolymer has an intrinsic viscosity of 0.01 to 20 dl/g, (E) the copolymer has a molecular weight distribution ( M w/ M n) of not more than 4, and (F) the copolymer has a crystallinity of 0 to 10%. A monomer selected from (a) alpha, beta-unsaturated carboxylic acids and/or their derivatives, (b) styrenes, (c) organic silicon compounds having an olefinically unsaturated bond and a hydrolyzable group, or (d) unsaturated epoxy monomers may be grafted on to the random copolymer. The random copolymer is produced by continuously copolymerizing ethylene with at least one cycloolefin in a hydrocarbon medium in the presence of a catalyst formed from a soluble vanadium compound and an organoaluminum compound while maintaining the atom ratio of aluminum atoms to vanadium atoms in the reaction system, AI:V at 2 or more:1. |