| In order to explain better the role of solid particles in the stabilization of emulsions, understanding the placement and positioning of solid particles at liquid-liquid interfaces becomes pertinent. Using a model fluid system of silicone oil, and water with silica and glass beads as solid particles, the behaviour of a retracting drop of water/oil with particles at the interface was experimentally studied as a function of particle wettability, particle size, silicone oil viscosity and radius of the capillary introducing the drop. The behaviour of the particles and droplet was found to depend on the particle size, wettability, and the silicone oil viscosity while the droplet behaviour was not affected by the capillary diameter. One other factor that affects the positioning of particles at a fluid-fluid interface, which has often been neglected in emulsion studies, is the line tension acting at the three-phase contact line. In this study, we have also been able to improve the interpretation of line tension measurements from the capillary rise in a conical tube by including the effect of interface deformation due to gravity. |
