Effect of hydrophilic macro-RAFT agent in surfactant-free emulsion polymerization

Here we report, synthesis of different molecular weight poly (styrene sulfonate) based macro-RAFT agents and their use as shell material in surfactant-free emulsion polymerization of styrene. Concentration and molecular weight of hydrophilic macro-RAFT agent has an influence on colloidal stability, particle size distribution and self-assembly. Microscopic and zeta-potential studies of colloids reveal that, the macro-RAFT agents used with low molecular weight (Mn = 1200) are comparable more efficient than high molecular weight (Mn = 46,800 and 116,000) for imparting narrow particle size distribution with good colloidal stability.