ABSTRACT
This chapter discusses the statistical thermodynamics of colloidal dispersions that consist of solid or fluid "particles" in a solvent. In colloidal dispersions there are two important lengths: the distance between colloidal particles and the size of the particles. Many industrial processes make use of colloidal dispersions of solid particles in fluids to tailor the hydrodynamic properties of the fluid or sometimes to produce a system with large amount of internal surface area for catalytic applications. While colloid stability is generally discussed in terms of nonequilibrium, irreversible flocculation, much of the underlying physics can be understood by focusing on the phase behavior of equilibrium ensembles of interacting particles. While an equilibrium solution of solutes that interact with surfaces usually results in an effective attractive interaction between the walls, nonequilibrium systems can show repulsive interactions. The chapter considers the balance of interactions for flat plates.
