Synthesis and Properties of Poly(N‐isopropylacrylamide‐co‐acrylamide) Hydrogels

Abstract Poly (N‐isopropylacrylamide‐co‐acrylamide) [Poly(NIPAAm‐co‐AAm)] with different feed ratios were obtained by radiation polymerization using Co 60 γ‐rays. Swelling equilibrium data in various media: deionized water, aqueous NaCl solutions and different pH buffer solutions, were determined. It appeared that the lower critical transition temperature (LCST) of the hydrogels increased with an increasing acrylamide content and decreased with increasing ionic strength. Moreover, LCST was affected by pH.