INTERFERENCE OF PHASE-SEPARATION AND GELATION - A ZEROTH-ORDER KINETIC-MODEL

We propose a Ginzburg-Landau-type model to describe the kinetics of mi xtures undergoing a sol-gel transition (nonconserved order parameter) simultaneously with phase separation (conserved order parameter). We c ompute the temporal development of the structure factor and determine the wave vector q(max) at which the structure factor is maximal. We fi nd that after a certain time t(f), q(max) saturates at a final value q (f), and we calculate the temperature dependence of both t(f) and q(f) . The predictions of this zeroth-order model agree remarkably well wit h recent kinetic measurements in gelatin-water-methanol mixtures.