Recent developments in self-healing composite materials: from autonomous repair to smart structural systems

Abstract

The self-healing feature of advanced types of intelligent materials reduces maintenance expenses and increases sustainability, along with improving durability and reliability. This review gives a comprehensive overview of the recent advancements made in the field of self-healing composite materials by considering their healing mechanisms, damage detection methods, new technologies, industrial applications, existing challenges, and future research perspectives. Along with the discussion about the extrinsic mechanisms, including the use of encapsulation, hollow fibers, and vascular systems, intrinsic healing mechanisms relying on dynamic covalent chemistry, supramolecular association, hydrogen bonding, metal–ligand coordination, and reversible polymer networks have been reviewed in this paper. Recent technological developments in relation to the design of intelligent material systems, additive manufacturing processes, multi-functional nanocomposites, vascular networks, and supramolecular polymers are critically analyzed. Moreover, real-time structural health monitoring technologies like electrical resistance sensors, electrical resistance tomography, as well as the effect of fiber volume fraction and fiber architecture on the electromechanical sensing technology, have been mentioned in the context of better damage detection and healing techniques. The aim of this study is to identify research gaps and suggest possible directions of future work in order to facilitate development and industrial applications of next-generation autonomous self-healing composites.