HARD-SPHERE COLLOIDAL SUSPENSION OF MACROPARTICLES IN A MULTICOMPONENT SOLVENT

Colloidal suspensions are represented as a mixture of macrospheres immersed in a multicomponent solvent of small spheres. The behavior of the macrospheres is analyzed on the basis of the Percu-Yevick theory when the ratios of the small to large sphere diameters go to zero at fixed packing fractions. Within the Baxter formalism the recent results of Biben and Hansen for the one component solvent are generalized. It is shown that the macrosphere suspension reduces to a one component system in which Baxter's function goes exactly over to that of a one component adhesive sphere fluid. The expression for the adhesiveness is exactly expressed in terms of the packing fractions of the solute and the solvent components. Such a model permits the interpretation of the flocculation phenomenon induced by the addition of free polymers in a colloidal suspension.