Adsorption Studies of Nonionic Surfactants onto Polyvinyltoluene Microlatexes in Aqueous Medium

Negatively charged polyvinyltoluene (PVT) microlatexes of various dimensions were prepared by polymerization of the corresponding vinyltoluene-in-water microemulsion precursors containing sodium dodecyl sulfate and n-pentanol. PVT microlatexes were used as adsorbents for adsorption of nonionic surfactants such as Tween 80, Tween 20, and Triton X-100. The extents of adsorption were known from the differences in the diffusion coefficient of the PVT microlatexes containing a solubilized suitable electro active probe. The surface excess (Gamma), equilibrium constant of adsorption (K(ads)), molecular cross-sectional surface area (sigma), intercalation ratio (kappa), etc., were determined for sodium dodecyl sulfate composition variation and ionic strength effects. A surface reconstruction model was proposed to rationalize the results. Copyright 2000 Academic Press.