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The living free radical ring-opening polymerization of 2-methylene-4-phenyl-1,3-dioxolane (MPDO) in the presence of ethyl α-bromobutyrate/CuBr/2,2'-bipyridine at various temperatures has been investigated. In comparison with the conventional ring-opening polymerization of MPDO, a lower content of ring-opened unit in the polymer was found. The results of ln[M] 0 /[M]) against polymerization time, (M n ) th and (M n ) NMR vs conversion, and GPC of the polymers are strongly indicative of the living polymerization process. Initiator efficiency was measured. The mechanism of polymerization, and the effect of pyridine on the polymerization mechanism were discussed.

This paper reports on the decisive effect that solvent has on the atom transfer radical polymerization of methyl methacrylate (MMA) at low temperature. In butanone and in the presence of a copper(I)/bipyridine complex, the polymerization is controlled and the molecular weight distribution is narrow, at 0 °C and even lower. This control is maintained when e-caprolactone (CL) is substituted for butanone. The use of this polymerizable solvent together with a novel dual initiator, 2-hydroxyethyl, 2'- methyl-2'-bromopropionate, is an efficient strategy to prepare PMMA-b-PCL diblock polymers in a one-pot process.