Enhanced Stabilization of Emulsions Due to Surfactant-Induced Nanoparticle Flocculation

Abstract

We have shown recently (Binks, B. P.; Rodrigues, J. A.; Frith, W. J. Langmuir2007, 23, 3626) that, for mixtures of negatively charged silica nanoparticles and cationic surfactant, oil-in-water emulsions are most stable to creaming and coalescence at conditions of maximum flocculation of particles by surfactant in aqueous dispersions alone. Here, we extend the idea using positively charged silica particles in mixtures with anionic surfactant.