Using Dispersion/Flocculation Phase Diagrams to Visualize Interactions of Associative Polymers, Latexes, and Surfactants

By Edward Kostansek

The colloidal interactions of associative polymers and latexes in the presence of surfactant are complex. This is because, in addition to good particle dispersion, both bridging and depletion flocculation can occur. Therefore, we have developed phase diagrams to help visualize these interactions. The various phases have a significant effect on coatings and applications properties.

Examples of phase diagrams are presented for a model HEUR nonionic associative polymer and latexes in the presence of sodium dodecylsulfate. The major variables affecting phase behavior were found to be associative polymer concentration, latex particle size, latex surface hydrophobicity, and electrolyte, cosolvent, and surfactant concentrations.