Scaling properties of the morphological measures at the early and intermediate stages of the spinodal decomposition in homopolymer blends

The spinodal decomposition of the homopolymer blends has been studied by the numerical integration of the Cahn-Hilliard-Cook equation. We have investigated the time evolution of the morphological measures that characterize quantitatively the interface in the system. For symmetric blends we have found that the Euler characteristic of the interface is negative and increases with time as tau(0.75) (connectivity of the domains decreases) regardless of the final quench temperature. The homogeneity index of the interface is constant in this case. This suggests that at the level of the integral geometry quantities (Minkowski functionals), the dynamic scaling hypothesis holds for the evolution of the interface morphology in quenched critical systems. The nonuniversal morphological evolution of the asymmetric blends have been studied. Also, we have shown that the thermal fluctuations can modify significantly the curvature distribution. (C) 2000 American Institute of Physics. [S0021-9606(00)50113-5].