Thermoresponsive polystyrene-<i style="">b</i>-poly(<i>N</i>-isopropylacrylamide) copolymers by atom transfer radical polymerization

Abstract

781-787Atom transfer radical polymerization has been employed for the polymerization of styrene initiated by ethyl-2-bromoisobutyrate in anisole at 100 °C with Cu(I)Br/PMDETA as the catalytic system. Kinetic investigations reveal that polymerization of styrene proceeds in a controlled manner with a first order plot of monomer consumption and with low polydispersity (Mw/Mn < 1.10). Well defined thermoresponsive diblock copolymer has been successfully synthesized using PS-Br macroinitiator. The amphilphilic behaviour of the diblock copolymers leads to phase separation resulting in two glass transition temperatures as detected by DSC. TGA analysis also shows the two-step decomposition