抗冻水凝胶的研究进展

Research Progress of Anti-freezing Hydrogels

水凝胶在柔性电极及电池、柔性传感器和软体机器人等领域具有巨大的应用潜力。为了解决水凝胶在低温下的性能减弱和失效问题,研究者们设计和制备了一系列抗结冰的水凝胶材料。本文综述了近期抗冻水凝胶的制备、性能与应用,主要讨论了不同抗冻介质体系的抗冻水凝胶,并对该领域所面临的挑战进行了讨论。

Hydrogels possess great application potential in the fields of flexible electrodes and batteries, flexible sensors and soft robots. Usually, hydrogels freeze and become rigid, brittle, and non-conductive when the temperature decreases below the freezing point of water, severely limiting their use in this temperature range. To solve the weakening and failure of hydrogel at low temperature, the researchers designed and prepared a series of anti-freezing hydrogel materials through various methods. Ionic compounds and organic anti-freezing solvents play important roles in anti-freezing hydrogels system, ionic compounds could lower the freezing point of hydrogels and also provide the conductive capacity of hydrogels. A high concentration of solutes(e.g., ethylene glycol, glycerol) is introduced into hydrogels to depress the water freezing point, and the combination of ionic compounds and organic anti-freezing solvents is applied to produce anti-freezing hydrogel materials. The mechanical flexibility, conductivity of the prepared hydrogels at subzero temperature were studied and measured. The response function at subzero temperature of the resulting hydrogel-based flexible electronics, such as a capacitive sensor, a resistive sensor and an actuator, were explored and developed. Recent progress made in preparation, properties and applications of anti-freezing hydrogels is reviewed, the prepared method which includes various anti-freezing solvent media systems was discussed, and the challenges in anti-freezing hydrogels such as biocompatibility, toxicity of anti-freezing solvents will be expected to be met and resolved.