Constructing conductive and mechanical strength self-healing hydrogel for flexible sensor

Flexible wearable sensors have profound research and development potential in fields such as intelligent wearable devices, electronic robots, and artificial intelligence. However, its failure due to mechanical damage caused by external reasons has become a significant obstacle to development. In this paper, poly(vinyl alcohol) (PVA) and 4-carboxylbenzaldehyde (CBA) were used to form a double network skeleton, and Polyaniline (PANI) was introduced to assemble a flexible sensor with excellent self-healing performance. The hydrophobic association of PVA and CBA guarantees the mechanical properties of the hydrogel sensor, and the introduction of PANI brings electrical properties to the hydrogel sensor. The flexible sensor prepared in this article has a sensitivity of 1.71 in the strain range of 0–300%, and a limit detection strain of less than 1%. The response time of the hydrogel sensor during stretching is 158 ms. In addition, the hydrogel sensor also has self-healing performance. At room temperature, after the hydrogel is cut, it only takes 1 min to complete the repair, and the self-healing rate is about 60%. Therefore, this kind of flexible, self-healing, conductive hydrogel sensor has broad research prospects in the future.