Recovery from applied strain in interpenetrating polymer network hydrogels with ionic and covalent cross-links

We have prepared an interpenetrating polymer network hydrogel based on the simultaneous formation of two polymer networks, gellan gum and poly(acrylamide). The gellan gum network is ionically cross-linked, while poly(acrylamide) network is covalently cross-linked. These gels can recover 53 ± 4% of the hysteresis of the first compressive cycle and 90 ± 9% of subsequent cycles.