Gelatin/PAM double network hydrogels with super-compressibility

In this work, the gelatin/PAM double network (DN) hydrogels with super-compressibility was prepared by heating, initiator-induced polymerization and cooling, in which gelatin with triple helix structures was used as rigid part and PAM was used as flexible part. Swelling ratio, mechanical properties, and shape memory properties were studied. Studies have shown that gelatin/PAM DN hydrogels not only has excellent compression resistance, compression strength is 87.57 MPa, fracture strain is >90%, dissipation energy is 29.35 MJ/m3, but also great shape memory performance can restore shape within 20 s. A sudden increase in stress during gelatin/PAM DN hydrogels compression was observed. We hypothesized the spiral beam separation model to explain the mechanical properties of gelatin/PAM dual network hydrogels. This model can better explain why the DN hydrogel has excellent compression performance.