Interactions of emulsion drops

summary We have describe three experimental methods using drops for the measurement of different aspects of the interactions between emulsion drops. The LSFA allows measurements of the capillary force and drop deformation of asized emulsion drop as it is pressed up to an oil-water interface. The forces and drop deformations are well described by theory using no adjustable parameters. The LSFA can also be used to determine disjoining pressure isotherms for film thickness 5 - 100 nm andvalues in the range 100 - 2000 Pa. The emulsion film contact angle method developed by Princen at al. can be used to determine the interaction energy per unit area for adhesive, non-coalescing drops.It has been successfully used to characterise a specific, salt induced interaction but could be extended to quantify other forces. disjoining pressure barrier to emulsion film rupture and drop coalescence. The different techniques yield complementary information and offer future promise to gain an increased quantitative and detailed understanding of the interactions of emulsion drops and their role in determining the emulsion stability.