Peter Reeves Sperry

A simple quantitative model for the volume restriction flocculation of latex by water-soluble polymers

Abstract Previously reported results on the flocculation of polystyrene latex by hydroxyethyl cellulose under conditions of no adsorption are satisfactorily interpreted by classical colloid potential energy theory containing a hard sphere approximation for the volume restriction attractive force set forth by Asakura and Oosawa.

Morphology and mechanism in latex flocculated by volume restriction

Examination of the secondary minimum flocculation of charge stabilized latex by nonadsorbed soluble polymer is extended to include the effects of latex particle size and soluble polymer concentration. Flocculation concentrations are quite accurately predicted by the simple modified DLVO theory presented earlier [J. Colloid Interface Sci. 87, 375 (1982)]. Floc morphology ranges from liquid-like to rigid, and the latter from relatively amorphous to pseudocrystalline, according to particle size and polymer concentration, and thus embraces in one experimental set several of the floc morphologies that have been observed in prior investigations of “weak flocculation.” These results also can be rationalized by the DLVO model.