Atom Transfer Radical Graft Copolymerization on a Poly(Epichlorohydrin-CO-Ethylene Oxide) (ECO) Elastomer

Abstract

Abstract Graft copolymerization by conventional radical polymerization leads to poor control in molecular weight and quite often gel formation because of several side reactions. In this investigation, PMMA was grafted on poly(epichlorohydrine-co-ethylene oxide) (ECO) elastomer by using ‘grafting from’ technique via atom transfer radical polymerization (ATRP), a very recently developed method of controlled radical polymerization. The pendant —Cl group in ECO rubber was activated by using CuBr catalyst and thus macromolecular chain in ECO rubber acted as macroinitiator. Grafting of PMMA on ECO was confirmed by FT-IR and NMR analyses. DSC traces showed two Tgs in PMMA grafted ECO rubbers indicating microphase separation of hard and glassy PMMA microdomains in the flexible elastomeric ECO matrix. Interestingly, there was large increase in tensile strength and tension set in the ECO-grafted-PMMA materials.