Controlled Synthesis of Polyelectrolytes by 4-Cyanopentanoic Acid Dithiobenzoate Mediated RAFT Polymerization

We reported controlled synthesis of methacrylic acid, 2-(diethylamino) ethyl methacrylate and 2-acrylamido-2-methyl-1-propa- nesulfonic acid (three electrolyte-type monomers) via reversible addition-fragmentation chain transfer (RAFT) polymerization with the chain transfer agent (CTA) (4-cyanopentanoic acid)-4-dithiobenzoate and initiator (I) 4,4′-azobis(4-cyanovaleric acid) in homogeneous aqueous media. Three distinct [monomer]0: [I]0: [CTA]0 ratios (50:0.2:1, 100:0.2:1, 500:0.2:1) were conducted. The polymerizations exhibited the characteristics of a controlled/"living" polymerization which demonstrated well-controlled molecular weight and low molecular weight distribution. Finally, the results of this investigation were used as a guide for the preparation of a series of well-defined polyelectrolytes (DPn = 50–500, PDI = 1.08–1.17) in high yield.