Shaping non-spherical Pickering droplets in yield stress fluid molds via arrest

P. Spicer, T. Atherton
UNSW Australia, AU

Keywords: soft matter, colloid and surface chemistry

Summary:

Particles with non-spherical shapes enhance the controlled uptake of pharmaceutical actives, alter thin film dynamics, and can be used to optimize granular flow behavior. Because of solubility requirements, however, many active ingredients must be delivered as liquid droplets and can not exploit advances in solid particle shape control. Our group is exploring various solutions to this problem by using fluid yield stress to preserve deformed liquid droplets in non-spherical shapes and then arrest their interface by colloidal adsorption. Careful adjustment of the relative rates of deformation, yielding, adsorption, relaxation, and arrest produces encapsulated droplets with stable, non-spherical shapes. The technique offers the potential for complex capsule shape production in a flowing system because of the flexibility of the liquid molds used.