Li Chun, Deng Xiaobo, Zhou Xiaohu
College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
Polymers (Basel). 2020 Nov 12;12(11):2670. doi: 10.3390/polym12112670.
Organohydrogels with distinct antifreezing and antidehydration properties have aroused great interest among researchers, and various organohydrogels and organohydrogel-based applications have emerged recently. There are two popular synthesis strategies to prepare these antifreezing and antidehydration organohydrogels: the in-situ gelling and the solvent displacement strategies. Although both strategies have been widely applied, there is a lack of comparative study of these two strategies. In this work, to elucidate the comparative advantages of the two synthesis strategies, we studied and compared the mechanical and environmental tolerant properties of the organohydrogels synthesized from both strategies. The glycerol-based and ethylene glycol-based chemical polyacrylamide (PAAm) organohydrogel and the glycerol-based physical gelatin organohydrogel were synthesized and studied. Through the comparative study, we have found that the organohydrogels from different strategies with the same dispersion medium showed similar antifreezing and antidehydration properties but different mechanical properties. The mechanical properties of these organohydrogels are influenced by two opposite factors for each strategy: the enhanced physical interactions induced strengthening and solvent effect or swelling induced weakening. We hope this study may provide a better understanding of the synthesis strategies of organohydrogels and provide a valuable guide to choose the suitable synthesis strategy for each application.
具有独特抗冻和抗脱水性能的有机水凝胶引起了研究人员的极大兴趣，近年来出现了各种有机水凝胶及其相关应用。制备这些抗冻和抗脱水有机水凝胶有两种常用的合成策略：原位凝胶化和溶剂置换策略。尽管这两种策略都已得到广泛应用，但缺乏对这两种策略的比较研究。在这项工作中，为了阐明这两种合成策略的比较优势，我们研究并比较了通过这两种策略合成的有机水凝胶的力学性能和环境耐受性。合成并研究了基于甘油和乙二醇的化学聚丙烯酰胺（PAAm）有机水凝胶以及基于甘油的物理明胶有机水凝胶。通过比较研究，我们发现来自不同策略且具有相同分散介质的有机水凝胶表现出相似的抗冻和抗脱水性能，但力学性能不同。这些有机水凝胶的力学性能受每种策略中两个相反因素的影响：增强的物理相互作用导致强化以及溶剂效应或溶胀导致弱化。我们希望这项研究能够更好地理解有机水凝胶的合成策略，并为每种应用选择合适的合成策略提供有价值的指导。
