Ab Initio Batch Emulsion RAFT Copolymerization of Styrene and Methyl Methacrylate Mediated by Poly[N-(4-vinylbenzyl)-N,N-Dibutylamine Hydrochloride] Trithiocarbonate: Effect of Monomer Component

Ab initio batch emulsion reversible addition-fragmentation chain transfer (RAFT) copolymerization of styrene and methyl methacrylate was investigated by employing poly[N-(4-vinylbenzyl)-N,N-dibutylamine hydrochloride] trithiocarbonate (PVBAH-TTC) both as surfactant and macro-RAFT agent. The effect of monomer component on the ab initio emulsion RAFT copolymerization was explored. It was found that the monomer composition had a great influence on the polymerization rate and well control of the polymerization. Enhanced St content in the monomer composition led to a fast polymerization rate and well controllability. The reason was attributed to the addition of the St, and the presence of styryl-terminated propagating radicals was more stable which improved the transfer reaction for the copolymerization and therefore the chain growth was well-controlled. Well-controlled polymerization with fast polymerization rate, high conversion and little coagulum was achieved under condition for the St monomer content above 30%. Generally, the polymerization led to formation of nano-sized core-shell poly[N-(4-vinylbenzyl)-N,N-dibutylamine]-b-poly(styrene-co-methyl methacrylate)-b-poly[N-(4-vinylbenzyl)-N, N-dibutylamine] (PVBA-b-P(St-co-MMA)-b-PVBA) triblock copolymer colloids, in which the hydrophilic P(St-co-MMA) blocks formed the shell and the hydrophobic PVBAH blocks formed the core.