Gelatin/PAM double network hydrogels with super-compressibility

• Published in: Polymer (Guilford) Vol. 210; p. 123021
• Main Authors: Lv, Baoqiang, Bu, Xiangqian, Da, Yinpeng, Duan, Penghui, Wang, Hao, Ren, Jingjing, Lyu, Bin, Gao, Dangge, Ma, Jianzhong
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2020; Elsevier BV
• Subjects: Cognitive ability; Compressibility; Compression; Compressive strength; Double network hydrogel; Gelatin; Gelatin/PAM; High mechanical toughness; Hydrogels; Mechanical properties; Shape memory; Shape memory hydrogels; Swelling ratio; Double network hydrogel; High mechanical toughness; Shape memory hydrogels; Gelatin/PAM
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2020.123021

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. [Display omitted] •A toughening mechanism of gelatin/PAM DN hydrogel was proposed.•Its mechanism mainly depends on the unwinding and reorganization of the three-stranded helical structure of gelatin.•Hydrogels have high dissipation energy, fatigue resistance and shape memory.