One-step synthesis of poly( N-vinylpyrrolidone)- b-poly( l-lactide) block copolymers using a dual initiator for RAFT polymerization and ROP.

ABSTRACT Amphiphilic, biocompatible poly( N-vinylpyrrolidone)- b-poly( l-lactide) (PVP- b-PLLA) block polymers were synthesized at 60 °C using a hydroxyl-functionalized N,N-diphenyldithiocarbamate reversible addition-fragmentation chain transfer (RAFT) agent, 2-hydroxyethyl 2-( N,N-diphenylcarbamothioylthio)propanoate (HDPCP), as a dual initiator for RAFT polymerization and ring-opening polymerization (ROP) in a one-step procedure. 4-Dimethylamino pyridine was used as the ROP catalyst for l-lactide. The two polymerization reactions proceeded in a controlled manner, but their polymerization rates were affected by the other polymerization process. This one-step procedure is believed to be the most convenient method for synthesizing PVP- b-PLLA block copolymers. HDPCP can also be used for the one-step synthesis of poly( N-vinylcarbazole)- b-PLLA block copolymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1607-1613 [ABSTRACT FROM AUTHOR]