METHOD FOR PRODUCING CYCLIC OLEFIN COPOLYMER

摘要

Provided is a method for producing a copolymer that makes it possible to obtain more of a cyclic olefin copolymer having excellent mechanical properties and a molecular weight suitable for ordinary molding by a smaller amount of catalyst. A method for producing a copolymer including a polymerization step for obtaining a copolymer by polymerizing at least a cyclic olefin monomer derived from norbornene (A) and an α-olefin monomer derived from a C4-C12 α-olefin (B) in the presence of an uncrosslinked ketimide-type half-titanocene catalyst and a cocatalyst made from alkyl aluminoxane; the amount of copolymer obtained in this polymerization step is 1000 g or higher per gram of this half-titanocene catalyst, and the number-average molecular weight of the copolymer is from 20,000 to 200,000.