Tunable oil-free capillary suspensions from aqueous two-phase systems

Food pastes, paints, inks, industrial slurries, cosmetic and pharmaceutical products are all suitable examples of goods that are delivered or processed as suspensions. Either as intermediate or final products, these suspensions require the fine tuning of their flow properties to meet specific processing or consumer demands like the consistency of skincare creams or mouth feel of food pastes. In this context, the recently developed concept of capillary suspensions constitutes a new option to tune the flow properties of suspensions.

Capillary suspensions are suspensions in which the addition of small amount (less than 1% by volume) of a second immiscible liquid in the continuous phase induce the formation of a sample-spanning particle network, resulting in significant changes in their rheological properties. These changes include orders of magnitude increase in the yield stress and low-shear viscosity. In this project, we forward the first completely water-based capillary suspensions using biocompatible polymers to offer an easy way to tailor suspension rheology in food, cosmetic and biomedical products.