The development of conductive hydrogels with outstanding mechanical properties, robust adhesion, and high sensitivity is still a major challenge. This study successfully addresses this issue by a multi-functional ionic conductive hydrogel based on a highly entangled double network (DN) structure with excellent mechanical properties, strong adhesion, high sensitivity and self-healing ability. Polyacrylic acid (PAAc)/chitosan (CS) constructed the Double Network with physical entanglement as the main effective crosslinking. The sliding entanglement points made the hydrogel show a more uniform directional network structure during stretching, and the energy dissipation was greatly reduced. Active chemically reactive polydopamine (PDA), CS, and PAAc are complexed with aluminum ions (Al) respectively (building appropriate chemical crosslinking networks), and Al acts as a “bridge” to build a hierarchical porous networks through multiple reversible coordination bond mediated interactions, alternating rigid and elastic domains, thereby improving the comprehensive performance of hydrogels. The tensile strength of PAAc/PDA/CS (ADC) was 173.4 kPa and the elongation at break was 921.9%, both of which were improved simultaneously. Moreover, ADC composite hydrogels exhibit excellent self-healing and adhesion properties, which can be attributed to the rich reversible/irreversible interactions brought about by PDA, with an impressive adhesion strength of 85.2 kPa on pig skin, further enhancing its practicality. Additionally, the ionic hydrogel demonstrates high strain sensitivity to tension, making it an ideal material for stable sensor signal output. The sensitivity coefficient (GF) reaches an impressive 11.24, highlighting the importance of this hydrogel in ensuring consistent and precise data collection. This innovative approach expands the idea and provides data support for the molecular structure design of high-performance wearable hydrogel sensors.

中文翻译：

---

用于运动检测的机械强度高、附着力强、自修复、导电的离子水凝胶

开发具有出色机械性能、强大粘附力和高灵敏度的导电水凝胶仍然是一个重大挑战。本研究通过基于高度纠缠双网络（DN）结构的多功能离子导电水凝胶成功解决了这一问题，该水凝胶具有优异的机械性能、强粘附力、高灵敏度和自修复能力。聚丙烯酸(PAAc)/壳聚糖(CS)构建了以物理缠结为主要有效交联的双网络。滑动缠结点使得水凝胶在拉伸过程中呈现出更加均匀的定向网络结构，能量耗散大大降低。活性化学反应性聚多巴胺（PDA）、CS和PAAc分别与铝离子（Al）络合（构建适当的化学交联网络），Al作为“桥梁”通过多个可逆配位键介导的相互作用构建分层多孔网络，交替刚性域和弹性域，从而提高水凝胶的综合性能。 PAAc/PDA/CS(ADC)的拉伸强度为173.4 kPa，断裂伸长率为921.9%，二者同时提高。此外，ADC复合水凝胶表现出优异的自修复和粘附性能，这得益于PDA带来的丰富的可逆/不可逆相互作用，在猪皮肤上的粘附强度高达85.2 kPa，进一步增强了其实用性。此外，离子水凝胶对张力表现出高应变敏感性，使其成为稳定传感器信号输出的理想材料。灵敏度系数 (GF) 达到令人印象深刻的 11.24，凸显了这种水凝胶在确保一致和精确的数据收集方面的重要性。这种创新方法拓展了这一思路，为高性能可穿戴水凝胶传感器的分子结构设计提供了数据支持。