Pan Xiaofeng, Wang Qinhua, Ning Dengwen, Dai Lei, Liu Kai, Ni Yonghao, Chen Lihui, Huang Liulian
College of Material Engineering, Fujian Agriculture and Forestry University, No. 15 Shangxiadian Road, Cangshan District, Fuzhou City, Fujian Province 350002, China.
College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
ACS Biomater Sci Eng. 2018 Sep 10;4(9):3397-3404. doi: 10.1021/acsbiomaterials.8b00657. Epub 2018 Aug 15.
Recently, flexible, injectable, and strain-sensitive hydrogels have attracted great research interest for application as electronic skin and wearable strain sensors. The synergistic integration of high flexibility, rapid self-healing, and antifreezing properties makes injectable, strain-sensitive, and self-healing guar gum hydrogels still a great challenge. Here, inspired by the strong hydrogen bonding of glycerol and water, the chelation cross-linking between glycerol and borax, we constructed a compact three-dimensional dynamic cross-linked net formed of glycerol-water-borax. Under stress, dynamic interactions of glycerol-water-borax net act as sacrificial bond energy for effective dissipation, which enables the hydrogel to achieve high flexibility, stretchability, and injectability. More importantly,because of the presence of glycerol, the antifreeze and moisturizing properties of the gel are improved. The hydrogel also exhibited an ultrafast self-healing ability of only 15 s. In addition, the results show that the hydrogel has self-adhesive properties and strain sensitivity. The hydrogels have the potential to be used to make flexible, wearable, and 3D-printable electronic skin and strain-sensitive sensors.
最近，柔性、可注射且对应变敏感的水凝胶作为电子皮肤和可穿戴应变传感器的应用引起了极大的研究兴趣。高柔韧性、快速自愈和抗冻性能的协同整合使得可注射、应变敏感且自愈的瓜尔胶水凝胶仍然面临巨大挑战。在此，受甘油与水之间强大氢键以及甘油与硼砂之间螯合交联的启发，我们构建了由甘油 - 水 - 硼砂形成的致密三维动态交联网络。在应力作用下，甘油 - 水 - 硼砂网络的动态相互作用充当牺牲键能量以实现有效耗散，这使得水凝胶能够实现高柔韧性、拉伸性和可注射性。更重要的是，由于甘油的存在，凝胶的抗冻和保湿性能得到改善。该水凝胶还表现出仅15秒的超快自愈能力。此外，结果表明该水凝胶具有自粘性和应变敏感性。这些水凝胶有潜力用于制造柔性、可穿戴和3D可打印的电子皮肤及应变敏感传感器。
