Synthesis and characterization of block comb-like copolymers P(A-MPEO)-block-PSt

Amphiphilic block comb-shaped copolymers, poly[poly(ethylene oxide) methyl ether acrylate]-block-polystyrene [P(A-MPEO)-block-PSt] with PSt as a handle, were successfully synthesized via a macromonomer technique. The reaction of MPEO with acryloyl chloride yielded a macromonomer, A-MPEO. The macroinitiator PSt capped with the dithiobenzoate group (PSt-SC(S)Ph) was prepared by reversible addition-fragmentation transfer (RAFT) polymerization of styrene in the presence of benzyl dithiobenzoate, and used as macroinitiator in the controlled radical block copolymerization of A-MPEO at room temperature under Co-60 irradiation. After the unreacted macromonomer A-MPEO had been removed by washing with hot saturated saline water, block comb-shaped copolymers were obtained. Their structure was characterized by H-1 NMR spectroscopy and gel permeation chromatography. The phase transition and self-assembling behaviour were investigated by atomic force microscope and differential scanning calorimetry. (C) 2004 Society of Chemical Industry.