Radical copolymerization of alkyl cyclobutenecarboxylates fused with cycloaliphatic framework with alkyl (meth)acrylates


Correspondence to: E. Ihara (E-mail: ihara@ehime-u.ac.jp)


Radical copolymerization behavior of alkyl cyclobutenecarboxylate-derivatives 4-6 and related norbornene-derived compounds 7–9 is described. A variety of alkyl cyclobutenecarboxylates fused with cycloaliphatic framework (4–6) were prepared by [2 + 2] cycloaddition of five, six, and eight-membered cycloolefins with alkyl propiolates [alkyl = Me, 2-hydroxyethyl, and 3-γ-butyrolactonyl (γ-BL)]. The fused cyclobutenecarboxylates 4–6 were radically copolymerized with n-butyl acrylate (nBA) to afford random copolymers, and terpolymerized with alkyl methacrylates with bulky ester groups [alkyl = γ-BL and 3-(3-methyladamantyl)]. The cyclobutane-containing bicyclic framework incorporated in the resulting polymer backbone contributes to raising Tg of resulting copolymers. Similar results were obtained when a mixture of related norbornene-derived compounds were used as monomers with an apparently enhanced Tg-raising effect in the copolymerization with nBA. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2716–2724