Well-defined vinyl ketone-based polymers by reversible addition - Fragmentation chain transfer polymerization

Well-defined photodegradable poly(vinyl ketone)s with predictable molecular weights and low polydispersities (PDI = 1.16-1.21) were synthesized by RAFT homopolymerizations of vinyl ketone monomers using (S)-1-dodecyl-(S′)-(α,α′-dimethyl-α′′-acetic acid)trithiocarbonate as the RAFT agent and AIBN as the initiator at 70-75 °C in 2-butanone or 1,4-dioxane. The living characteristics of the RAFT processes were verified by excellent linearity agreement of polymer Mn values and monomer conversions to polymer. Further chain extension from these poly(vinyl ketone)s by subsequent RAFT polymerizations provided well-defined block copolymers. Confirmed by AFM characterization, a nanostructured film was prepared from a resulting diblock copolymer based on photodegradation of its poly(vinyl ketone) blocks.