The initial spinodal decomposition kinetics of colloidal systems under shear

Abstract The influence of a shear flow on the initial spinodal decomposition kinetics is described on the basis of “the Liouville equation for colloidal systems”, the Smoluchowski equation. With a well-founded “local equilibrium closure” for the pair-correlation function, a closed equation of motion for the one-particle density is obtained. Its solution predicts decomposition kinetics characteristics which are in complete agreement with experimental results on a binary liquid mixture. We also discuss the dependence of the location of the spinodal curve and the cloud-point curve on the shear-rate. Due to the fact that the pair-correlation function is regularly distorted for small distances but singularly distorted for large distances, the spinodal and cloud-point curve no longer coincide for systems under shear. This is confirmed by experiments on a polymer/polymer/solvent mixture.