New polymethylene-b-poly(styrene-co-2-hydroxyethyl methacrylate) and polymethylene-b-poly(styrene-co-2-hydroxyethyl methacrylate)-g-poly(ε-caprolactone)) copolymers: Synthesis, characterization and their application in the fabrication of highly ordered porous films

A series of new polymethylene-b-poly(styrene-co-2-hydroxyethyl methacrylate) (PM-b-P (St-co-HEMA)) and polymethylene-b-poly(styrene-co-2-hydroxyethyl methacrylate-g-poly (s-co-2-hydroxyethyl)) (PM-b-P(St-co-HEMA-g-PCL)) copolymers were successfully synthesized via a strategy combined polyhomologation of ylides, reversible addition-fragmentation chain transfer (RAFT) polymerization and ring-opening polymerization (ROP). Firstly, a hydroxyl terminated polymethylene (PM-OH) was obtained via polyhomologation of ylides followed by oxidation. Then, PM-OH was transformed to a macromolecular chain transfer agent (PM-CTA). Subsequently, RAFT copolymerizations of styrene (St) and 2-hydroxyethyl methacrylate (HEMA) were performed using PM-CIA as chain transfer agent, targeting the well-defined PM-b-P (St-co-HEMA) copolymers with controllable molecular weight and narrow molecular weight distribution. Finally, the ring-opening polymerization of e-caprolactone was carried out using PM-b-P(St-co-HEMA) copolymer as initiator to achieve PM-bP(St-co-HEMA-g-PCL) copolymer. The molecular weight and chain structure of the obtained copolymers were characterized by gel permeation chromatography (GPC), proton nuclear magnetic resonance (H-1 NMR) and Fourier Transform Infrared spectroscopy (FTIR). Moreover, the fabrication of highly ordered porous films using the amphiphilic PM-b-P(Stco-HEMA) copolymers via a static breath-figure process was investigated. (C) 2014 Elsevier Ltd. All rights reserved.