Influence of wetting and adhesion on dynamic drying of a hydrogel disk

Hydrogels are elastic polymer-based materials that are highly water absorbent. While they are widely used in industry, e.g., to make contact lenses, microfluidic devices, or flexible electronics, their poroelastic behavior, and in particular their drying dynamics, is not well understood. Here, we investigate how different boundary conditions can lead to different compacting patterns of the skeletal polymer network and subsequent different drying dynamics over time. For example, by modifying only the boundary conditions, we are able to induce a growing, constant, or descending drying rate. We then use confocal microscopy measurements to develop a quantitative analytical model to predict drying under various environmental conditions.