Synthesis of well‐defined amphiphilic graft copolymer bearing poly(2‐acryloyloxyethyl ferrocenecarboxylate) side chains via successive SET‐LRP and ATRP

Abstract

Abstract A series of well‐defined ferrocene‐based amphiphilic graft copolymers, consisting of poly( N ‐isopropylacrylamide)‐ b ‐poly(ethyl acrylate) (PNIPAM‐ b ‐PEA) backbone and poly(2‐acryloyloxyethyl ferrocenecarboxylate) (PAEFC) side chains, were synthesized by the combination of single‐electron‐transfer living radical polymerization (SET‐LRP) and atom transfer radical polymerization (ATRP). A new ferrocene‐based monomer, 2‐(acryloyloxy)ethyl ferrocenecarboxylate (AEFC), was prepared first and it can be polymerized via ATRP in a controlled way using methyl 2‐bromopropionate as initiator and CuBr/PMDETA as catalytic system in DMF at 40 °C. PNIPAM‐ b ‐PEA backbone was synthesized by sequential SET‐LRP of NIPAM and HEA at 25 °C using CuCl/Me 6 TREN as catalytic system followed by the transformation into the macroinitiator by treating the pendant hydroxyls with α‐bromoisobutyryl bromide. The targeted well‐defined graft copolymers with narrow molecular weight distributions ( M w / M n < 1.20) were synthesized via ATRP of AEFC initiated by the macroinitiator. The electro‐chemical behaviors of PAEFC homopolymer and PNIPAM‐ b ‐(PEA‐ g ‐PAEFC) graft copolymer were studied by cyclic voltammetry. Micellar properties of PNIPAM‐ b ‐(PEA‐ g ‐PAEFC) were investigated by transmission electron microscopy and dynamic light scattering. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4346–4357, 2009