Abstract: A phenomenological mode! for dispersed systems which exhibit complex theological behaviour such as shear and time-dependent viscosity, yield stress, and elastici'y is proposed. The model extends the Quemeda model to describe the viscosity function with a structural parameter A which varies according t'o different kinetic orders of particle aggregation and segregation. The transient stress response is obtained by solving on instantaneous Maxwell model with an assumed shear modulus function G of the same form...