Atom Transfer Radical Copolymerization of Styrene and Poly(ethylene oxide)-alkyl Methacrylate Macromonomer

Abstract

The present paper focuses on the atom transfer radical copolymerization of styrene and an amphiphilic macromonomer poly(ethylene oxide)-alkyl methacrylate (PEOm) which contains a hydrophilic polyethylene oxide segment and a hydrophobic alkyl chain. These block-copolymers were prepared using CuBr/bipy (bipy:2,2'bipyridine) catalyst system in conjunction with ethyl 2-bromoisobutyrate, as initiator, using o-xylene as a solvent at 90 ºC. The number-average molecular weights of the resulting block copolymers increased in direct proportion to the monomer conversion and the molecular weight distributions (Mw/Mn) were as low as 1.45. Thus a novel type of block-polymacromonomers with controlled chain lengths for both the backbone and the side chain have been synthesized. The resulting copolymers were characterized by means of room temperature gel permeation chromatograph and ¹H NMR spectroscopy, FT-IR spectroscopy and differintial scanning calorimeter.