A novel electrolytic-zwitterionic (EZ) monomer, Sodium N-(3-sulfopropyl)-3-(N,N-diallylamino)propanesulfonate, on homopolymerization in aqueous solution using tert-butylhydroperoxide, afforded the poly(electrolyte-zwitterions) (PEZ). The copolymer of the above monomer and sulfur dioxide was also synthesized in excellent yield. The EZ monomer as well as the PEZs contains structural features common to both polyzwitterions and conventional polyelectrolytes. The solution properties of these polymers were studied in detail. The PEZ, as the name implies, possess dual type of structural character and it is the electrolytic portion of the structure that dictates the solubility and viscosity behavior of the polymers. (C) 2003 Elsevier Ltd. All rights reserved.