Reversible addition-fragmentation chain-transfer polymerization for the synthesis of poly(4-acetoxystyrene) and poly(4-acetoxystyrene)-block-polystyrene by bulk, solution and emulsion techniques

The living radical polymerization of 4-acetoxystyrene via the RAFT process has been achieved employing bulk, solution and emulsion techniques. The rat e of polymerization was stated between 60 degreesC and 90 degreesC. Increas ing the temperature increases the rate of polymerization without affecting the polydispersity. Poly(4-acetoxystyrene) with narrow polydispersity (1.08 ) Was obtained. Various novel dithiocarboxylic esters and dithiocarbamates were screened as chain-transfer agents for the RAFT polymerization of 4-ace toxystyrene. The block copolymerization of poly(4-acetoxystyrene) with to p oly(4-acetoxystyrene)-block polystyrene confirmed the presence of active ch ant ends in the first block. The acetoxy polymers were hydrolyzed to the co rresponding hydroxy polymers under mild basic conditions.