Recent advancements in self-healing materials: Mechanicals, performances and features

Abstract The material would inevitably suffer a series of damages in operation, including cracks, piercing and delamination, which would lead to a degradation of performance and even cause safety problems. Self-healing materials could partially or completely heal themselves after being damaged, so that the performance of materials could be restored to the original state. In this review, we focus on the self-healing materials in mechanicals, performances and features. We classified the self-healing materials based on the two strategies including extrinsic mechanism and intrinsic mechanism. The main difference between the two strategies is whether the healing agent is added during the self-healing process. The principles, preparation methods and self-healing properties of microcapsule technology, hollow fiber technology and microvascular technology based on extrinsic mechanism are reviewed. The mechanical properties and self-healing properties of intrinsic self-healing materials are discussed based on non-covalent bond interaction and covalent bond interaction. Several typical instances to outline the applications of self-healing materials, including wearable sensors, supercapacitors, batteries, and sensors, are provided. Finally, the future development and outlook of self-healing materials were discussed.