Dynamics of colloid particle interaction. Incomplete desorption relaxation

We present a novel approach to the stability of lyophobic colloids by considering transient double-layer disequilibration of interacting particles. Deviations from equilibrium are accounted for via perturbation theory. Incomplete equilibration is related to a retarded desorption of charge-determining ions, which, in turn, leads to an increment in the disjoining pressure. The theory is elaborated for two interacting spheres and it is shown that under realistic conditions the relaxation retardation may become substantial. Under conditions where the relaxation retardation dominates, the stability ratio becomes independent of particle size.