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Macromonomers by activated polymerization of oxiranes. Synthesis and polymerization
Authors:Tadeusz Biedron  Krystyna Brzezinska  Przemyslaw Kubisa  Stanislaw Penczek
Abstract:Macromonomers were obtained by cationic polymerization of propylene oxide and epichlorohydrin proceeding by the activated monomer mechanism with hydroxyethyl acrylate as initiator. Up to DP n ~ 15 for propylene oxide and DP n ~ 20 for epichlorohydrin, polymerization proceeds as a living process, giving with quantitative yields macromonomers with functionality equal to one, controlled molecular weight and narrow molecular weight distribution (M wM n<1.2) free of side products. In the higer molecular weight region, side reactions become increasingly noticeable. Propylene oxide macromonomers undergo radical homopolymerization. Homopolymerization of macromonomer with M n = 8×102 gives graft copolymers with M n up to 7.2×103 in copolymerization with styrene, completely soluble graft copolymers with M n ~ 2×104 were obtained. Radical copolymerization of epichlorohydrin macromonomers with styrene gives initially soluble products with M n ~ 6×104 were obtained. Radical copolymerization of epichlorohydrin macromonomers with styrene gives initially soluble products with Mn~ 6×104, which are converted in the later stages into insoluble gels, apparently due to the chain transfer to chloromethly groups of the polyepichlorohydrin chains.
Keywords:macromonomers  activated monomers  graft copolymers
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