Zwitterionic Poly(betaine-N-isopropylacrylamide) Microgels: Properties and Applications

We report the synthesis of zwitterionic poly(N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl) ammonium betaine-isopropylacrylamide)) (poly(NIPAm-SPP)) microgels prepared by free-radical precipitation polymerization. We investigated the influence of the amount of SPP and the effect of the variations in temperature, pH, and electrolyte concentration on the microgel dimensions. In the range of the concentrations of SPP studied in the present work, no expected antipolyelectrolyte behavior of the microgels was observed and the particles showed polyelectrolyte properties. The zwitterionic properties of the microgels were used for in situ template-based synthesis of gold, silver, and bimetallic gold-silver nanoparticles.