(411e) Retraction Behavior of Highly Stretchable Hydrogels with Different Structures

High-modulus, stretchable, and resilient hydrogels have many potential uses, including prosthetic devices, artificial skin, electronic devices, and soft robotics. Elastomeric biopolymers, such as resilin, exhibit high stretchability and resilience, enabling power-amplified movement in many species necessary for feeding and defense mechanisms. We have synthesized highly stretchable polyacrylamide (PAAm) hydrogel with different volume fractions through UV curing. These gels are highly stretchable and retract quickly when released from a stretched state. We will also present results for a bioinspired hydrogel consisting of hydrophobic and hydrophilic components. These gels are synthesized via free radical polymerization of acrylic acid (AAc), methacrylamide (MAM), and poly (propylene glycol) diacrylate (PPGDA). The structures of these gels are complex compared to PAAm hydrogels because of the presence of the hydrophobic segment, PPGDA. We will compare the large strain mechanical responses and retraction behavior for PAAm and AAc/MAM/PPGDA hydrogels with different structures. Our findings will lead to a better understanding of hydrogel structure-property relationships, which are vital for their use in various applications.