The instability of silica sol in concentrated solutions of Triton X100

An excess of nonionic surfactant, Triton X100, in the continuous phase of silica sol has strong consequences on the stability of silica dispersions. Beyond full coverage, the surfactant may give rise to the formation of either fractal or dense aggregates. The structure of aggregates has been studied through SAXS. It has been demonstrated that hydration of the components is an essential ingredient which influences the interparticle interactions. Some comparisons with current theoretical models developed for depletion flocculation are made. (C) 1998 Academic Press.