Thin film breakage in oil--in--water emulsions, a multidisciplinary study

Abstract Coalescence is a critical phenomenon in separation and transport processes. An improved understanding of coalescence can enhance current models predicting emulsion stability and separation. We here report a combined experimental and simulation study to investigate the thin film prior to its rupture in a coalescence event. Optical tweezers measured the influence of ions and of surface-active agents on coalescence time and the forces acting between colliding oil droplets. Molecular simulation described the composition and constituent distribution of the thin films in systems comparable with the ones investigated via optical tweezers. We identify a potential relationship between the disruption of the electrical double layer and the formation of nanocrystals with the thin film breakage times and depletion forces.