Disulfide bonds are commonly exploited as dynamic crosslinks to fabricate degradable self-healing hydrogels. However, the low energy dissipation capability and low density of disulfide crosslinks in the hydrogel networks give these hydrogels poor mechanical properties, slow and non-autonomous self-healing, and incomplete polymer degradation. This paper reports a strategy for synthesizing multifunctional hydrogels by copolymerizing 2,3-dimercapto-1-propanol and meso-2,3-dimercaptosuccinic acid, yielding a dynamic poly(disulfide) backbone and numerous rapidly reversible physical crosslinks (H-bonds and ionic interactions). The high-density disulfide bonds and multiphysical crosslinkers synergistically provide the hydrogels with extremely fast self-healing in air and underwater, extraordinary stretchability, and complete and fast degradability. The hydrogels show various functionalities including three-dimensional printability in air and underwater, good electrical conductivity, non-cytotoxicity and bio-tissue adhesion. This strategy opens a new route for exploiting degradable self-healing multifunctional hydrogels with extraordinary features for biomedical and engineering applications.

通常使用二硫键作为动态交联来制备可降解的自愈水凝胶。然而，水凝胶网络中的低能量耗散能力和低密度的二硫键交联使这些水凝胶的机械性能差，缓慢且非自主的自我修复以及聚合物降解不完全。本文报道了一种通过将2,3-二巯基-1-丙醇和meso-2,3-二巯基琥珀酸共聚来合成多功能水凝胶的策略，产生了动态的聚（二硫键）主链和许多快速可逆的物理交联键（H键和离子键）互动）。高密度的二硫键和多物理交联剂可协同作用，使水凝胶在空气和水下具有极快的自愈性，出色的可拉伸性以及完全而快速的降解性。水凝胶具有多种功能，包括在空气和水下的三维可印刷性，良好的导电性，无细胞毒性和生物组织粘附性。该策略为生物医学和工程应用中具有非凡功能的可降解自修复多功能水凝胶的开发开辟了一条新途径。