SWELLING BEHAVIOR OF SUBMICRON GEL PARTICLES

We prepared submicron Poly(N-isopropylacrylamide) gel particles. Their swelling behavior was investigated by a photon correlation spectrosco py (PCS) technique. The swelling behavior of submicron gel particles s howed a continuous volume phase transition for various temperatures. W e combined the extended Flory-Huggins model for mixing solvent and net work with a modified Flory-Rehner theory for the elastic contribution. The proposed model agreed very well with swelling behaviors of both s ubmicron gel particles and bulk gels. A continuous volume phase transi tion behavior of submicron gel particles was predicted successfully by the proposed model. (C) 1998 John Wiley & Sons, Inc.