Modeling droplets swelling and escape in double emulsions using population balance equations

Monitoring the physical stability of double emulsions is considered in this work. A coupled population balance equation model for the inner and outer droplets is developed. The model involves a sub-model describing swelling of the inner, and so of the outer, droplets and a sub-model describing the escape of the inner droplets. The swelling phenomena is governed by the osmotic and Laplace pressures while the inner droplet escape rate is governed by the balance of the surface and viscous forces of the droplets. Experimental investigations demonstrate the usefulness of the model and its capability to describe the evolution of the inner and outer droplets size distributions and the release rate during storage of the double emulsions.