Shear yield stress of partially flocculated colloidal suspensions

A general expression was derived for the shear yield stress of a flocculated suspension of particles that is able to describe the effect of particle-size distribution, solid loading, pH, and hence, electrokinetics of the suspension. The model builds on an earlier model by incorporating the effect of the repulsive interaction between particles. Scaling of the data to the maximum yield stress at a given volume fraction provides a means of removing particle-size- and volume-fraction-related effects. The scaling process establishes that to a high level of precision, concentrated dispersions act, in interparticle interaction terms, as the sum of two-body interactions.