Compatibilization of titanium dioxide powders with non-polar media: Adsorption of anionic surfactants and its influence on dispersion stability

Abstract

The effect of the adsorption of an anionic surfactant (aerosol OT, sodium dodecyl sulfate, sodium dodecyl sulfonate, or sodium dodecyl benzene sulfonate) on the dispersion behavior of some types of titanium dioxide pigments has been studied. Surfactant adsorption isotherms and the kinetics of the adsorption process were linked using a full Langmuir model. Sedimentation experiments were used to assess the dispersibility of the powders in two non-polar dispersion media (nonane and cyclohexane). Surfactant-modified powders were found to be more dispersible than the untreated powders in these non-polar media. Experiments were also performed to assess the stability of the surfactant coating to elevated temperatures and exposure to organic solvents.