One-pot synthesis of poly(N-vinylcaprolactam)-based biocompatible block copolymers using a dual initiator for ROP and RAFT polymerization

• Published in: Polymer (Guilford) Vol. 54; no. 22; pp. 6119 - 6124
• Main Authors: Yu, Young Chang, Li, Guoxue, Kim, Jinsang, Youk, Ji Ho
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 18.10.2013; Elsevier
• Subjects: Applied sciences; biphenyl; body temperature; composite polymers; Dual initiator; Exact sciences and technology; hydrophobicity; One-pot synthesis; Organic polymers; Physicochemistry of polymers; polymerization; Polymers with particular properties; Preparation, kinetics, thermodynamics, mechanism and catalysts; PVCL-based biocompatible block copolymers; One-pot synthesis; PVCL-based biocompatible block copolymers; Dual initiator; Ring opening polymerization; One pot reaction; Vinyl derivative copolymer; Lactone copolymer; Composition effect; Experimental study; Cloud point; Free radical polymerization; Chain transfer; Caprolactone copolymer; Organic dithiocarbonate; Preparation; Diblock copolymer; Living copolymer; Aqueous solution; Micellar solution; Amphiphilic polymer; Successive reaction
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2013.09.013

Thermosensitive, biocompatible poly(ε-caprolactone)-b-poly(N-vinylcaprolactam) (PCL-b-PVCL), poly(δ-valerolactone)-b-PVCL, and poly(trimethylene carbonate)-b-PVCL block copolymers were synthesized at 30 °C using a hydroxyl-functionalized xanthate reversible addition-fragmentation chain transfer (RAFT) agent, 2-hydroxyethyl 2-(ethoxycarbonothioylthio)propanoate (HECP), as a dual initiator for ring-opening polymerization (ROP) and RAFT polymerization in a one-pot procedure. The hydrophobic blocks were first synthesized by the ROP of cyclic monomers using diphenyl phosphate (DPP) as a catalyst and the RAFT polymerization of the PVCL block was followed by adding N-vinylcaprolactam (VCL) and 2,2′-azobis(4-methoxy-2,4-dimethyl valeronitrile) (V-70) as an initiator to the reaction mixture. This novel one-pot process is convenient and powerful method for the synthesis of the PVCL-based biocompatible block copolymers. The lower critical solution temperature (LCST) of the PVCL-based biocompatible block copolymer can be readily tuned by controlling the hydrophobicity of the block copolymers. By copolymerizing a hydrophilic N-vinylpyrrolidone moiety to the PVCL blocks by RAFT copolymerization, the LCST of the copolymer was matched with the body temperature for its future biomedical applications. [Display omitted]