Developing shape memory hydrogel strain sensors with both high mechanical property and stable electrical performance is a challenge. Here, a hydrogel based on gelatin was reported as a strain sensor. The hydrogel was developed by gelatin grafted polypyrrole, polyacrylamide and tannic acid. The gelatin moieties were exploited to form a water-soluble conductive polymer, endowing the hydrogel with shape memory behavior and addressing the challenge of low conductivity induced by structural inhomogeneity and aggregation of conductive nanomaterials. Tannic acid was introduced to provide hydrogen-bonding and π−π stacking interactions to promote hydrogel mechanical properties. The hydrogel achieved a maximum tensile strength of 1.44 ± 0.11 MPa, maximum toughness of 2581 ± 453 kJ/m³ and maximum conductivity of 0.58 ± 0.10 S/m. Results demonstrated that the hydrogel showed shape memory property and can respond to and discern different motions. This achievement offers an opportunity to facilitate significant shape memory conductive hydrogel strain sensor with both high mechanical property and stable electrical performance.

开发兼具高机械性能和稳定电性能的形状记忆水凝胶应变传感器是一项挑战。在这里，基于明胶的水凝胶被报道为应变传感器。该水凝胶由明胶接枝聚吡咯、聚丙烯酰胺和单宁酸开发而成。利用明胶部分形成水溶性导电聚合物，赋予水凝胶形状记忆行为，并解决由结构不均匀性和导电纳米材料聚集引起的低电导率的挑战。引入单宁酸以提供氢键和 π-π 堆积相互作用，以提高水凝胶的机械性能。水凝胶的最大拉伸强度为 1.44 ± 0.11 MPa，最大韧性为 2581 ± 453 kJ/m ³最大电导率为 0.58 ± 0.10 S/m。结果表明，水凝胶具有形状记忆特性，可以响应和辨别不同的运动。这一成就为促进具有高机械性能和稳定电性能的重要形状记忆导电水凝胶应变传感器提供了机会。