Adenine-mediated adhesive and tough hydrogel based on hybrid crosslinking

作者:Zhang, Qin; Liu, Xin; Ren, Xiuyan; Duan, Lijie*; Gao, Guanghui*
来源:European Polymer Journal, 2018, 106: 139-147.
DOI:10.1016/j.eurpolymj.2018.07.018

摘要

Adhesive hydrogels tend to exhibit poor mechanical property, therefore it's still challenging to integrate excellent adhesiveness and toughness in one hydrogel. In this work, we utilized a hybrid crosslinking strategy to design an adenine-mediated hydrogel by introducing adenine and N,N'-methylene bisacrylamide (MBA) into polyacrylamide hydrogel. The hybrid crosslinking hydrogel exhibited a tunable adhesive performance and mechanical strength, based on the balance of cohesion and adhesion through changing the contents of acrylated adenine (Aa) and MBA. The hydrogel can adhere to various solid substrate surfaces strongly as well as biological tissue. The hybrid crosslinking hydrogel also exhibited repeatable and durable adhesiveness, which still possessed robust adhesion on aluminum substrate after 20 peeling cycles. In addition, the synergistic effect of the physical and chemical crosslinking in the hydrogel network endowed hydrogel with superior mechanical properties. The hybrid crosslinking hydrogel could be stretched to over 2700% with fracture stress of 127 kPa and toughness of 931 kJ/m(3). Meanwhile, the hydrogel displayed excellent self-recover ability and fatigue resistance. The adenine-mediated hybrid crosslinking hydrogel shows potential as materials for tissue engineering.