Polymerization kinetics and modeling of a metallocene cyclic olefin copolymer system

Cyclic olefin copolymers (COCs) have received increasing attention owing to their unique properties and extensive applications, especially in biomedical and photo-optic areas. The applications of COCs depend on the glass transition temperature of the copolymers. The composition of a particular copolymer largely determines the glass transition temperature of such a copolymer. This study presents a polymerization mechanism and model for the ethylene-norbornene copolymerization. Effects of operating conditions such as ethylene pressure, catalyst concentration, and cocatalyst ratio on the product properties including molecular weight, copolymer composition and structure, and copolymer yields are discussed. The kinetic parameters were obtained by minimization of residues between calculated results and experiments conducted in a laboratory scale reactor. The proposed model can facilitate the design and the operation of polymerization reactors. (C) 2002 Elsevier Science Ltd. All rights reserved.