Intrinsic and extrinsic self-healing fiber-reinforced polymer composites: A review

With their high specific modulus, high specific strength and designability, fiber-reinforced polymer (FRP) composites have replaced or surpassed traditional metallic materials in a wide range of applications. However, the polymer matrix of commonly used FRP composites is usually a thermosetting polymer that is difficult to rework once formed, which implants a substantial challenge for the repair and recycling of composites. Self-repair, as an emerging method of repairing polymer-based materials, has the advantages of simplification, high efficiency and repeatability against traditional repair methods. Research on self-healing polymer materials is developing rapidly and becoming more systematic. With the development of self-healing polymer, polymer-based composites with self-healing capabilities are becoming possible. This paper reviews the current development of self-healing polymers in recent years, with specific emphasis on their applications in FRP composites. According to the difference in healing mechanisms, the self-healing polymer composites are split into two categories, intrinsic and extrinsic ones. The essential concepts and different types of intrinsic and extrinsic self-healing composites are first introduced. Then, their pros and cons are discussed, respectively. Finally, the perspectives of intrinsic as well as extrinsic self-healing FRP composites are put forward. HighlightsDevelopment of self-healing fiber-reinforced polymer composites.Extrinsic and intrinsic self-healing fiber-reinforced polymer composites.Pros and cons of self-healing fiber-reinforced polymer composites.Perspectives of self-healing fiber-reinforced polymer composites.