Molecular Engineering by Cationic Polymerization Techniques

Understanding the mechanism of cationic olefin polymerization has led to the synthesis of various new materials of interesting and unusual physical properties. By elucidating details of initiation, various new graft and bigraft copolymers combining glassy/glassy, glassy/rubbery, and rubbery/rubbery sequences have been obtained. Recent research concerning fundamentals of alkylation and termination was exploited for the preparation of new block copolymers and terminally-functional block copolymers. Initiation by difunctional initiators has led to α,ω-difunctional polymers, e. g., !α,ω-diphenylpolyisobutylene. Cyclo-pentadienylation of lightly chlorinated polymers, e. g., chlorobutyl rubber, produced thermally reversible networks.