Poly(vinylidene chloride)-Based Amphiphilic Block Copolymers

Abstract

The controlled/living free-radical copolymerization of vinylidene chloride (VDC) with methyl acrylate (MeA) or acrylic acid (AA) was studied by the reversible addition–fragmentation chain transfer (RAFT) technique using a trithiocarbonate RAFT agent. The reactions were performed in 1,4-dioxane solution at 30 °C and led to good control and high chain-end functionality. P(VDC- co -MeA)- b -PAA, PAA- b -P(VDC- co -MeA), and PAA- b -P(VDC- co -AA) amphiphilic block copolymers were then prepared in the same conditions, starting either from a hydrophobic P(VDC- co -MeA) macromolecular RAFT (macro-RAFT) agent or from a hydrophilic PAA one. The advantage of the first synthesis pathway relies on the very good transfer efficiency to trithiocarbonate-ended P(VDC- co -MeA) and on the rapid consumption of the latter even when low percentages (10 mol %) of MeA comonomer are incorporated in the macro-RAFT agent. In contrast, for the second approach a rapid consumption of the macro-RAFT agent is only reached with 30 mol % of MeA in the comonomer feed, whereas with 10 mol % of MeA the transfer constant was determined to be only close to 1. Finally, we demonstrated that PAA- b -P(VDC- co -AA) diblock copolymers might also be obtained with controlled features in a one-pot process.