Numerical Studies of Phase Separation in Models of Binary Alloys and Polymer Blends

We review some recent results concerning numerical studies of the Cahn-Hilliard equation in three dimensions to describe the phase separation process in a mixture after a quench within the coexistence curve. We focus on the late time behavior for two experimentally relevant systems: binary alloys and binary polymer blends. We find that, in both systems, dynamical scaling with a time dependent characteristic length R ( t ) holds at sufficiently late times and that the late-time behavior for R ( t ) can be described by a modified Lifschitz-Slyozov law: R ( t ) = c + dt n , where n = 1/3. For polymer mixtures, the independence of the growth law exponent n of the quench temperature is in contradiction with some recent experiments on polymer systems.