A Conductive, Self-Healing Hybrid Hydrogel with Excellent Water-Retention and Thermal Stability by Introducing Ethylene Glycol as a Crystallization Inhibitor
A Conductive, Self-Healing Hybrid Hydrogel with Excellent Water-Retention and Thermal Stability by Introducing Ethylene Glycol as a Crystallization Inhibitor
复制标题
通过引入乙二醇作为结晶抑制剂，形成具有优异保水性和热稳定性的导电、自修复混合水凝胶
DOI：
10.1016/j.colsurfa.2020.125443
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发表时间：
2020-12-20
影响因子：
5.2
通讯作者：
Qiu, Xiaoyong
中科院分区：
文献类型：
--
作者：
Zhao, Yiming;Yan, Yonggan;Qiu, Xiaoyong
柔性电子学的快速发展促使人们设计和合成在恶劣环境下具有良好伸长性和导电性的稳定水凝胶。传统水凝胶的长期耐久性在高温下通常会失效。本工作通过将丙烯酰胺(AM)和超支化聚乙烯亚胺(PEI)在高盐度的乙二醇水溶液中进行紫外光固化，研制出一种具有良好的水锁和粘接性能的耐高温、自愈的杂化水凝胶。采用乙二醇作结晶抑制剂，大大提高了醋酸钠的溶解度。制备的水凝胶可以在100℃下保持75%的初始重量9小时，或在15%相对湿度(RH)的环境下保持88%的初始重量77小时。脱水凝胶在高温(例如100摄氏度)下长期储存后是柔软的(拉伸应变>；1700%)和导电性。此外，高盐度水凝胶在空气中表现出显著的吸水能力：在高温或低湿度条件下失水后可恢复到原来的重量。此外，分离出的水凝胶碎片可在30 S内愈合成一块，并且水凝胶对有机物质(猪皮6.2kPa，木材28kPa)和无机物质(玻璃111.9 kPa，铁135.5 kpa)具有至少5个循环的可逆粘附性。这项工作为获得可在高温下工作的多功能导电水凝胶提供了一种简便的方法，展示了工程应用的长期前景。
The rapid development of flexible electronics motivates the design and synthesis of stable hydrogels that possess good stretchability and conductivity under harsh environment. The long-term durability of traditional hydrogels generally fails at high temperatures. In this work, a high-temperature-tolerant, self-healable hybrid hydrogel showing excellent water-locking and adhesive properties was developed through ultraviolet curing of acrylamide (AM) and hyper-branched polyethyleneimine (PEI) in highly salted ethylene glycol-water solution. Ethylene glycol was used as a crystallization inhibitor and greatly enhanced the solubility of sodium acetate (NaAc). The fabricated hydrogel can retain 75 % of its initial weight for 9 hours at 100 degrees C or 88 % of its initial weight for 77 hours at 15 % relative humidity (RH) environment. The dehydrated gel was flexible (tensile strain > 1700 %) and conductive after storing at high temperatures (e.g. 100 degrees C) for a long term. Moreover, the highly salted hydrogel showed remarkable water adsorbing ability in the air: it can recover to its original weight after losing water at high temperature or low humidity conditions. In addition, the separated hydrogel fragments could heal into a single piece in 30 s, and the hydrogel showed reversible adhesiveness to both organic (6.2 kPa for pigskin, 28 kPa for wood) and inorganic (111.9 kPa for glass, 135.5 kPa for iron) substances for at least 5 cycles. This work provides a facile way of obtaining multi-functional conductive hydrogels that can work at high temperatures, demonstrating long-term prospects in engineering applications.