Synthesis of core–shell polystyrene nanoparticles by surfactant free emulsion polymerization using macro-RAFT agent

Abstract

Novel approach for the synthesis of core–shell polystyrene nanoparticles by living hydrophilic polymer consisting of thiocarbonyl thio end group is reported. The surfactant free emulsion polymerization of styrene in the presence of macro-RAFT (reversible addition fragmentation chain transfer) agent is carried out to synthesize stable latex particles with smaller particle size. A macro-RAFT agent is prepared by homopolymerization of sodium styrene sulfonate (NaSS) in aqueous phase by using dithioester as chain transfer agent. This synthesized polystyrene sulfonate–sodium (PSS–Na) based macro-RAFT agent, which is essentially water soluble macromolecular chain transfer agent used for the surfactant-free batch emulsion polymerization of styrene. Transmission electron microscopy (TEM) study of the synthesized colloids shows the narrow particle size distribution with core–shell morphology.