A Novel Strategy to Synthesize Double Comb‐Shaped Water Soluble Copolymer by RAFT Polymerization

Summary: A double comb‐shaped water soluble copolymer, poly[poly(ethylene oxide) methyl ether methacrylate]‐block‐poly(N‐isopropylacrylamide)‐block‐poly[poly (ethylene oxide) methyl ether methacrylate], abbreviated as [P(MA‐MPEO)‐block‐PNIPAM‐block‐P(MA‐MPEO)], with a controlled molecular weight and narrow polydispersity was successively synthesized using a macromonomer technique. The 60Co γ irradiation polymerization of MA‐MPEO in the presence of dibenzyl trithiocarbonate (DBTTC) at room temperature afforded a polymer, P(MA‐MPEO)‐SC(S)S‐P(MA‐MPEO), which was subsequently used as a macro RAFT agent in the RAFT polymerization of N‐isopropylacrylamide, and water soluble double comb‐shaped copolymers, P(MA‐MPEO)‐block‐PNIPAM‐block‐P(MA‐MPEO), were successfully obtained. Structure of the double comb‐shaped copolymer. image Structure of the double comb‐shaped copolymer.