Kinetic study of swelling of rubbery poly(ethyl methacrylate) networks in 2-hexanone

The kinetics of the swelling of cross-linked poly(ethyl methacrylate) gels in 2-hexanone was studied at temperatures varying from 70.0 to 85.0 degrees C. The sorption curves exhibit the characteristic features of transport processes, apparently the Fickian diffusion of fast rates. The data were analyzed successfully by the contemporary model of Li and Tanaka, resulting in the cooperative diffusion coefficient, D-c, and the ratio of the shear modulus to the longitudinal osmotic modulus. It has been established empirically that the D-c is a composite function consisting of an Arrhenius expression and two simple power laws of the number-average molecular weight between cross-links and the equilibrium volume fraction of the gel. On the basis of the present findings, the quality of the swelling agent is discussed. (C) 1997 Elsevier Science Limited.