Stability of colloids and the Deryagin-Landau-Verwey-Overbeek theory of surface forces (DLVO)

The modern status of the theory of surface forces and the theory of stabili ty of colloids is reviewed. The role of B.V. Deryagin and his scientific sc hool in the development of this theory is considered. It is emphasized that the DLVO theory is not the theory of stability of colloids but the theory of surface forces acting between sol particles. The coagulation of sols inv olves aggregation-disaggregation processes, which lead to the formation of an equilibrium sol (with respect to these processes) with a lower concentra tion. Surface forces alone do not determine the stability of a system, beca use, depending on the concentration of particles in the dispersed phase, th e same depth of the potential well may correspond to stable and unstable sy stems.