Finite deformation of fast-response thermo-sensitive hydrogels - A computational study

This computational study investigates three-dimensional, finite deformation of four common shapes - rod, disc, cube, and sphere - for fast-response, thermo-sensitive hydrogels. These hydrogels have an inherent advantage in their fast-response to stimuli, making them attractive components for a wide range of applications. Here, two basic hydrogels with varying compositions are considered: semi-interpenetrating-networked and macroporous poly(N-isopropylacrylamide). The predicted equilibrium swelling and deformation kinetics are calibrated and validated with their experimental counterparts. In short, the results suggest that the deformation kinetics of a hydrogel is significantly influenced by its geometry; however, the equilibrium swelling ratio of the hydrogels is found to be independent of their geometries. Within the mathematical framework one can also explore the stress distribution within the hydrogels as well as other related parameters. In addition, the model can be extended to account for other stimuli, such as glucose and alcohol.