THE HUGGINS COEFFICIENT FOR THE SQUARE-WELL COLLOIDAL FLUID

The Huggins coefficient, which characterizes the exact, dilute limitin g viscosity of colloidal suspensions with square-well interactions, is calculated. An overview of the method and numerical results are prese nted for both monodisperse and bidisperse suspensions of spherical col loids. The results demonstrate that attractions increase the viscosity much more than repulsions of similar magnitude, Further, the viscosit y of polydisperse suspensions of these particles is very sensitive to the smaller size fraction. These calculations complement other theoret ical work on the equilibrium thermodynamic properties and colloidal di ffusion to provide a more complete reference state for analyzing the r ole of colloidal potentials on suspension properties.