Bivalent monomer bearing styryl and five‐membered cyclic dithiocarbonate moieties for orthogonal radical and cationic ring‐opening polymerizations

Abstract

We synthesized a novel bivalent monomer 1 bearing 4‐vinylbenzyl group and five‐membered cyclic dithiocarbonate. This monomer 1 was polymerized orthogonally by free radical polymerization to afford polystyrene 1a bearing a five‐membered cyclic dithiocarbonate moiety in the side chain. On the other hand, cationic ring‐opening polymerization of five‐membered cyclic dithiocarbonate in the monomer 1 successfully proceeded, resulting in a narrow molecular weight distribution of polydithiocarbonate 1b bearing a 4‐vinylbenzyl group in the side chain. Furthermore, post‐polymerizations of 1a and 1b maintaining the polymerizable functionality were carried out respectively by suitable polymerization methods. The five‐membered cyclic dithiocarbonate of 1a underwent cationic ring‐opening polymerization with a high molar ratio of methyl trifluoromethanesulfonate at a high temperature compared to the case of monomer 1, whereas radical polymerization of the 4‐vinylbenzyl group of 1b successfully proceeded under the almost same conditions as the case of monomer 1. These post‐polymerizations achieved the synthesis of corresponding networked polymers 2a and 2b.