High Strain Deformation of a Strain Stiffening Gel

In many applications swollen gels are subjected to high strain deformation. In this study we report high strain deformation behavior of a thermoreversible, strain stiffening polymer gel, consisting of a triblock copolymer, poly(methyl methacrylate)–poly(n-butyl acrylate)–poly(methylmethacrylate) (PMMA–PnBA–PMMA) in 2-ethyl-1-hexanol. Gels with different polymer volume fractions are investigated using shear and cavitation rheology experiments. Stress vs. strain responses from the large amplitude oscillatory shear (LAOS) experiments display distinct non-linear behavior. As observed in cavitation rheology experiments, these gels cavitate at a critical pressure to accommodate an elastic instability. Different constitutive models are investigated to obtain the mechanical properties of these gels from cavitation experiments.