Deswelling Kinetics of a Porous Poly(N-isopropylacrylamide/methacrylic acid) Gel Prepared by Freeze-Drying

A linear correlation between the enthalpy of activation ((delta)H(not equal)) and the entropy of activation ((delta)S(not equal)) was observed for the deswelling process of porous poly(Nisopropylacrylamide/methacrylic acid) gels. The free energy of activation ((delta)G(not equal)) was nearly constant at +84 (plus-minus) 2 kJ mol^-1 irrespective of the methacrylic acid content and pH of the solutions.