Functional group selective polymerization of (4-maleimidophenyl)oxirane as a new type of bifunctional monomer

Abstract

A novel bifunctional monomer, (4-maleimidophenyl)oxirane (MAPO), with very reactive maleimido and epoxy groups, was prepared through the selective oxidation of the two carbon–carbon double bonds of N-(4-vinylphenyl)maleimide. Either of the two different polymerizable groups (vinylene of the maleimide moiety and the mono-substituted epoxide) of MAPO was able to be selectively polymerized by choosing the polymerization method. For radical polymerization, MAPO gave poly{ p-[1,2-(epoxyethyl)phenyl]maleimide} (PEPM) with dense pendent epoxy groups in 76% yield without cross-linking. MAPO also gave poly(maleimidostyrene oxide) (PMSO) with dense pendent maleimido groups through cationic polymerization in 60% yield. On the other hand, anionic polymerization with an of MAPO produced only insoluble gel-like materials due to unselective polymerization of the two polymerizable groups ( Scheme 1). The vinylene group of the maleimide moiety in PMSO easily reacted with the mercapto group, and the ring-opening reaction of the epoxy groups in PEPM with amino groups took place.