Arresting Bubble Coarsening: Gelling from Liquid to Solid Foams – ABC2FOAM

The properties of aqueous foams are largely dictated by capillary effects as surface forces dominate their structure, ageing and rheology. The solidification of the continuous phase takes us into the world of solid mechanics with fixed structures, and very different evolution and mechanical properties. In between these two extremes lies a wide range of systems including aerated foods and materials processed for construction, in which both capillarity and the continuous phase mechanics play a role. This is the playground of ABC2FOAM.
We will create gelling and solidifying foams with varyingly stiff continuous phases. We will carry out a combined rheological and structural characterisation of these foams in time. This will allow us to delimit the region between capillary and solid foams. The role of walls is crucial in the study of foam rheology or flow and we will also quantify the impact of solid surfaces on the properties of the gelling foams.
The results will accelerate the use of foamy materials in applications where the use of bubbles is sought to create more ecological systems. In addition to clarifying the conditions of stability, we expect to create materials with unusual structures and novel properties, as hinted by recent structures observed during the coarsening of foams in elastic media.