School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, P. R. China.
State Key Laboratory for Marine Corrosion and Protection, Luoyang Ship Material Research Institute (LSMRI), Qingdao, 266237, P. R. China.
Chempluschem. 2020 Sep;85(9):2158-2165. doi: 10.1002/cplu.202000520.
Introducing self-healing properties into hydrogels can prolong their application lifetime. However, achieving mechanical strength without sacrificing self-healing properties is still a major challenge. We prepared a series of zwitterionic polymer hydrogels by random copolymerization of zwitterionic ionic monomer (SBMA), cationic monomer (DAC) and hydrophilic monomer (HEMA). The ionic bonds and hydrogen bonds formed in the hydrogels can efficiently dissipate energy and rebuild the network. The resulting hydrogels show high mechanical strength (289-396 KPa of fracture stress, 433-864 % of fracture stress) and have great fatigue resistance. The hydrogel with a 1 : 1 molar ratio of SBMA:DAC possesses the best self-healing properties (self-healing efficiency up to 96.5 % at room temperature for 10 h). The self-healing process is completely spontaneous and does not require external factors to assist. In addition, the hydrogel also possesses notch insensitivity with a fracture energy of 12000 J m . After combining the conductivity of RGO aerogel, the hydrogel/RGO composites show good strain sensitivity with high reliability and self-healing ability, which has certain significance in broadening the application of these zwitterionic hydrogels.
将自修复特性引入水凝胶中可以延长其应用寿命。然而，在不牺牲自修复性能的情况下实现机械强度仍然是一个主要挑战。我们通过将两性离子离子单体（SBMA）、阳离子单体（DAC）和亲水单体（HEMA）进行无规共聚制备了一系列两性离子聚合物水凝胶。水凝胶中形成的离子键和氢键可以有效地耗散能量并重建网络。得到的水凝胶具有较高的机械强度（断裂应力为 289-396 KPa，断裂应力为 433-864％）和优异的耐疲劳性能。SBMA:DAC 摩尔比为 1:1 的水凝胶具有最佳的自修复性能（在室温下 10 h 内自修复效率高达 96.5％）。自修复过程完全是自发的，不需要外部因素的辅助。此外，该水凝胶还具有切口不敏感性，断裂能为 12000 J m 。将 RGO 气凝胶的导电性结合起来，水凝胶/RGO 复合材料具有良好的应变敏感性和高可靠性以及自修复能力，这对于拓宽这些两性离子水凝胶的应用具有一定的意义。
