Xu Chenggong, Xie Ao, Hu Haiyuan, Wang Zhengde, Feng Yange, Wang Daoai, Liu Weimin
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2025 Mar 16;16(1):2589. doi: 10.1038/s41467-025-57800-y.
Ultrastrong gels possess generally ultrahigh modulus and strength yet exhibit limited stretchability owing to hardening and embrittlement accompanied by reinforcement. This dilemma is overcome here by using hyperhysteresis-mediated mechanical training that hyperhysteresis allows structural retardation to prevent the structural recovery of network after training, resulting in simply single pre-stretching training. This training strategy introduces deep eutectic solvent into polyvinyl alcohol hydrogels to achieve hyperhysteresis via hydrogen bonding nanocrystals on molecular engineering, performs single pre-stretching training to produce hierarchical nanofibrils on structural engineering, and fabricates chemically cross-linked second network to enable stretchability. The resultant eutectogels display exceptional mechanical performances with enormous fracture strength (85.2 MPa), Young's modulus (98 MPa) and work of rupture (130.6 MJ m), which compare favorably to those of previous gels. The presented strategy is generalizable to other solvents and polymer for engineering ultrastrong organogels, and further inspires advanced fabrication technologies for force-induced self-reinforcement materials.
超强凝胶通常具有超高的模量和强度，但由于在增强过程中会出现硬化和脆化现象，其拉伸性有限。本文通过使用超滞后介导的机械训练克服了这一难题，超滞后使得结构迟缓，从而防止训练后网络结构的恢复，进而实现简单的单次预拉伸训练。这种训练策略将低共熔溶剂引入聚乙烯醇水凝胶中，通过分子工程上的氢键纳米晶体实现超滞后，在结构工程上进行单次预拉伸训练以产生分级纳米纤维，并制造化学交联的第二网络以实现拉伸性。所得的低共熔凝胶具有出色的力学性能，其断裂强度（85.2兆帕）、杨氏模量（98兆帕）和断裂功（130.6兆焦/平方米）都非常高，与之前的凝胶相比具有优势。所提出的策略可推广到其他溶剂和聚合物，用于制备超强有机凝胶，并进一步启发了力致自增强材料的先进制造技术。
