Self‐healable and thiol–ene UV‐curable waterborne polyurethane for anticorrosion coating

Abstract

ABSTRACT Thiol–ene ultraviolet‐curable waterborne polyurethane (WPU) crosslinked networks capable of self‐healing of cracks were developed for anticorrosion coating application. The healing mechanism is attributed to the rearrangement of the crosslinked networks caused by triethylamine‐catalyzed thiol–disulfide exchange reaction proved by high‐performance liquid chromatography, gel permeation chromatography, and rheology tests. The crack remendability can be repeated for at least two times as demonstrated by visual inspection. Moreover, the self‐healing effect was further demonstrated in terms of corrosion and electrochemical tests. Comparatively, the control specimens without disulfide bonds were not self‐healable. The present study provides a simple way for achieving self‐healing WPU to conform to the trend of development of high performance and environmental friendly anticorrosive coatings. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47700.