Hydrogels are flexible materials that have high potential for use in various applications due to their unique properties. However, their applications are greatly restricted by the low mechanical performance caused by high water content and inhomogeneous networks. This paper reports a universal strategy for easily preparing hydrogels that are tough and stretchable without any special structures or complicated processes. Our strategy involves tuning the polymerization conditions to form networks with many polymer chain entanglements to achieve energy dissipation. Tough and stretchable hydrogels can be prepared by free radical polymerization with a high monomer concentration and low cross-linker content to optimize the balance between physical and chemical cross-links by entanglements and covalent bonds, respectively. The strategy of using polymer chain entanglements for energy dissipation allows us to overcome the limitation of low mechanical performance, which leads to the wide practical use of hydrogels.

水凝胶是柔性材料，由于其独特的性能而具有在各种应用中使用的高潜力。但是，它们的应用受到高含水量和不均匀网络导致的低机械性能的极大限制。本文报告了一种通用策略，可轻松制备坚韧且可拉伸的水凝胶，而无需任何特殊结构或复杂过程。我们的策略涉及调整聚合条件，以形成具有许多聚合物链缠结的网络，以实现能量消散。可以通过具有高单体浓度和低交联剂含量的自由基聚合反应来制备坚韧且可拉伸的水凝胶，以分别通过缠结和共价键来优化物理和化学交联之间的平衡。