RAFT cryopolymerizations of acrylamides and acrylates in dioxane at −5 °C

Reversible addition-fragmentation chain transfer (RAFT) cryopolymerizations of acrylamides and acrylates were successfully carried out at −5 °C with cumene hydroperoxide/ascorbic acid as redox initiation couple and 2-dodecylsulfanyl- thiocarbonylsulfanyl-2-methylpropinoic acid as chain transfer agent. The cryopolymerization features of N,N-dimethylacrylamide (DMA) and tert-butyl acrylate (tBA) were investigated in view of kinetics, molecular weight and its distribution by proton nuclear magnetic resonance analysis and gel permeation chromatography. Furthermore, sequential block cryopolymerizations of N-isopropylacrylamide were performed with the obtained trithiocarbonate- functionalized PDMA or PtBA as macro-CTA and the corresponding block polymers were obtained. All the results demonstrated that these cryopolymerizations bear all the characteristics of controlled/living radical polymerizations.