IGM Colloquium: Gel Mechanics, by Prof. Lallit Anand

There are numerous elastomeric materials which can absorb large quantities of suitable fluids without the essential skeletal network structure of the elastomer being disrupted by the action of the fluid. Such a polymer network, together with the fluid molecules, forms a swollen aggregate called an elastomeric gel.

We have formulated a continuum‐mechanical theory to describe the various coupled aspects of fluid permeation and large deformations (e.g., swelling and squeezing) of elastomeric gels. We have also numerically implemented our theory, and solved several interesting boundary‐value problems of engineering interest. If the concentration of the solvent or the deformation is increased to substantial levels, especially in the presence of flaws, then the gel may rupture. While, the understanding and modeling of the effects of fluid diffusion on the damage and fracture of polymeric gels is still in its infancy, I will also discuss a thermodynamically‐consistent theory for fracture of polymeric gels ‐‐‐ a theory which accounts for the coupled effects of fluid diffusion, large deformations, damage, and also the gradient effects of damage.