Research progress of high-strength self-healing polymer materials: Balance between mechanical strength and self-healing efficiency

In recent years, self-healing polymer materials, as novel and advanced materials, have garnered significant attention. Through physical and chemical methods, various advanced functions have been incorporated into them, sparking the curiosity of both the scientific community and industries. However, these materials usually suffer from relatively low mechanical strength, which significantly reduces their service life, reliability, and safety, while severely limiting their practical applications. This review comprehensively explores the underlying causes of the incompatibility between self-healing performance and mechanical strength in such materials. To overcome this problem, three design strategies for high-strength self-healing polymers are proposed: bionic design that mimics the self-healing mechanism of organisms; system design that constructs multiple networks based on molecular structures and balances performance; and composite strategy that utilizes the enhanced properties of nanomaterials and optimizes performance. These strategies address the incompatibility issue directly and are expected to achieve a balance between self-healing efficiency and mechanical strength. Finally, future challenges and prospects of high-strength self-healing polymer materials are outlined.