Multi-action self-healing coatings with simultaneous recovery of corrosion resistance and adhesion strength. (28th February 2022)

• Record Type: Journal Article
• Authors: Ren, Chenhao; Huang, Yao; Hao, Wenkui; Zhang, Dawei; Luo, Xiejing; Ma, Lingwei; Wang, Jinke; Chowwanonthapunya, Thee; Dong, Chaofang; Li, Xiaogang
• Is Part Of: Journal of materials science & technology. Volume 101(2022)
• Page Start: 18
• Page End: 27
• Publication Date: 2022-02-28
• Subjects: Self-healing coating -- Corrosion protection -- Adhesion strength -- Shape memory effect -- Bonding effect; Metals -- Periodicals; Materials science -- Periodicals; Materials science; Metals; Periodicals; 620.1105
• DOI: 10.1016/j.jmst.2021.05.070
• Languages: English
• ISSNs: 1005-0302

Abstract

Highlights: Ce(NO3 )3 -EVA microspheres were embedded into corrosion resistance coating to achieve the self-healing property. The coating could simultaneously recover the corrosion resistance and the adhesion strength. A semi-coherent network was formed in the coating by the fusion of Ce(NO3 )3 -EVA microspheres. Self-healing efficiency was improved by the shape memory effect of epoxy and the semi-coherent network of microspheres. Abstract: In this study, a new self-healing strategy that can simultaneously recover the corrosion resistance and the adhesion strength of coatings was introduced. The coating was based on a shape memory epoxy resin containing ethylene vinyl acetate (EVA) microspheres loaded with Ce(NO3 )3 inhibitors, and was cured at a relatively high temperature to facilitate the fusion of adjacent microspheres for a strengthened self-healing effect. The electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) results demonstrated that the shape memory effect of epoxy matrix, the filling of molten EVA microspheres as well as the release of Ce(NO3 )3 inhibitors contributed synergistically to suppress the corrosion reaction at the coating damage. After healing, the low frequency impedance modulus of the coatings containing Ce(NO3 )3 -EVA microspheres was three orders of magnitude higher than that of the blank epoxy coating. The adhesion strength of the coatings containing Ce(NO3 )3 -EVA microspheres on the metal substrate was also largely repaired thanks to the strong bonding effect of the EVA microspheres. Graphical abstract: Image, graphical abstract