Anionic Hybrid Copolymerization of Cyclic and Vinyl Monomers without Transesterification

Abstract Anionic hybrid copolymerization (AHcP) of cyclic and vinyl monomers provides a powerful strategy to synthesize biodegradable heteropolymers. However, transesterification between comonomeric units often happens making the mechanism complex. Here, AHcP of N,N‐dimethylacrylamide (DMA) with ε‐caprolactone (CL) is investigated at 25 °C, where DMA does not have ester group so that no transesterification between DMA and CL units happens. Nuclear magnetic resonance (NMR) and matrix‐assisted laser desorption/ionization time of flight mass spectrometry measurements reveal that DMA and CL units are randomly distributed in the resulted polymer. Differential scanning calorimetry measurements show that the copolymer has only one glass transition temperature (Tg). Thermogravimetric analysis demonstrates the copolymer has a single‐stage decomposition from 255 to 425 °C, which is between those of the corresponding homopolymers. Thes facts further indicate that the copolymer is random. This study clearly demonstrates that AHcP takes place regardless of transesterification though it may have some effects.