The copolymerization of 1,5-cyclooctadiene and norbornene in the presence of an electrochemically generated WCl6-based catalyst was investigated. This copolymer was isolated and characterized by H-1, and C-13 NMR spectroscopy to analyse in detail the nature of homo- and heterodyad units and GPC analysis (Mn = 11200, PDI = 2.0). Homopolymerizations of 1,5-cyclooctadiene and norbornene were also studied and resulting polymers were characterized by spectroscopic methods to discuss with copolymers. Glass-transition temperatures of homo- and copolymers were determined by DSC. (C) 2004 Elsevier Ltd. All rights reserved.