KINETICS OF HETEROCOAGULATION .3. ANALYSIS OF EFFECTS CAUSING THE DISCREPANCY BETWEEN THE THEORY AND EXPERIMENT

The kinetics of heterocoagulation in mixed colloidal systems, consisting of pairs of uniform spherical particles of cerium (hydrous) oxide, silica, and polystyrene latex, was studied by a low angle light scattering technique. The experimentally determined initial rates disagreed with values calculated by the conventional theories for stability of lyophobic colloids. The effects of higher order aggregate formation, surface hydration, and discreteness of charge on the stability of mixed dispersions were evaluated in order to reconcile the observed discrepancies.