盐度超敏感离子水凝胶的制备及其在可视化盐度检测和智能液体阀上的应用

Synthesis of salinity ultra-sensitive ionic hydrogels for visual salinity detection and usage as an intelligent liquid valve

对超低浓度盐溶液响应产生大尺度形变的功能水凝胶在海水渗透能收集、刺激响应分离材料、智能传感和致动器等方面具有广阔的应用前景.本文结合聚电解质和两性离子聚合物开发了一种盐度超敏感离子水凝胶.以稀盐作为分散介质时,水凝胶体积缩小为原来1/60.本文研究了盐响应水凝胶的溶胀、形态和力学性能,并基于拉曼光谱对聚合物网络盐响应重构行为进行了表征.此外,利用毛细管和盐响应水凝胶成功设计了一种可视化、便携离子检测计,可媲美商用水质监测计.同时开发了具有传感和致动功能的智能液阀,用于自动感应调节液体的流出和输送.该盐敏感水凝胶在淡水监测和调控、海水渗透能收集、刺激响应分离材料、智能软机器人和电子穿戴等方面具有很大的应用潜力.

Functional hydrogel materials with large-scale deformation induced by ultra-low salinity as an external sti-mulus have promising applications in seawater osmotic energy harvesting,stimulus-responsive separation materials,in-telligent sensors,and actuators.A salt-responsive hydrogel undergoing large volumetric changes(~1/60)with the use of dilute salt solution(0.01-0.6 wt%NaCl)is designed via facile random copolymerization of polyelectrolyte and zwitterionic polymer chains in this study.The salt-responsive swelling/deswelling properties,morphologies,and mechanical prop-erties of the prepared hydrogels are systematically examined.Internal reconfiguration of distinct polymeric networks is characterized by different salinity percentages via Raman spectroscopy.Subsequently,a portable ion-detection device comprising easy-to-access capillary tubes and salt-responsive hydrogel is successfully designed and compared with a com-mercial water quality monitoring device.Moreover,intelligent liquid valves with autosensing and actuating functions are developed for the regulation of liquid leakage and transport using the same salt-sensitive hydrogel.It is highly expected that these salinity ultra-sensitive ionic hydrogels would have great potential in monitoring and regulating freshwater re-sources,seawater osmotic energy harvesting,stimulus-re-sponsive separation materials,and intelligent soft robotics and electronics.