Build a bridge from polymeric structure design to engineering application of self-healing coatings: A review

• Published in: Progress in organic coatings 2022-06, Vol.167, p.106790, Article 106790
• Main Authors: Cheng, Meng, Fu, Qiang, Tan, Bin, Ma, Yue, Fang, Liang, Lu, Chunhua, Xu, Zhongzi
• Format: Article
• Language: English
• Subjects: Addition polymerization; Bridges; Coatings; Composites; Crack closure; Cracks; Dispersion; Fillers; High performance; Industrial engineering; Multi-functions; Polymer coatings; Polymers; Self healing materials; Self-healing; Structural design
• ISSN: 0300-9440; 1873-331X
• DOI: 10.1016/j.porgcoat.2022.106790

From civil to industrial engineering, coating can be found almost everywhere. In practical application, the change of external environment causes coating cracks, resulting in the deterioration of performance and/or functions. When damage occurs, it not only increases replacement cost, but involves safety issues as well. Although endowing coatings with self-healing capability can eliminate coating cracks, there is still a big gap between academic research and applications. In this review, we summarize research progress of intrinsic self-healing coatings in recent years, focusing on structural design of polymers, filler components and dispersion mechanism, to provide thoughts for the exploitation of potential applications of self-healing composite coatings with high performance and multi-functions. Intrinsic self-healing coatings can only be repaired after cracks are closed, that is, self-healing behavior consists of two stages: crack closure and healing. Therefore, closing and healing mechanisms of reported self-healing polymeric structures are introduced. In addition, the relationship between the choice of functional fillers and self-healing performance is focused for the creation of high performance and/or multi-functions self-healing composite coatings. The development prospect of remote healing composite coatings is prospected as well. Finally, the dispersion mechanism of fillers in coatings is discussed to construct self-healing composite coatings composed of polymers and fillers, which can realize the characteristics of high performance, multi-functions and self-healing. •The design and preparation of self-healing composite coatings is reviewed.•Closing mechanism, healing mechanism and their mutual relationship are introduced.•High-performance or multi-functions fillers for self-healing coatings are reviewed.•The dispersion mechanism of fillers in coatings is discussed.