Improvement of corrosion resistant of waterborne polyurethane coatings by addition of modified graphene oxide

Abstract Traditional waterborne polyurethane (WPU) coatings are limited in use due to its low crosslink density and poor adhesive properties. In this study, four types of toluene diisocyanate-functionalized graphene oxide (TGO-1, TGO-2, TGO-3, and TGO-4) were prepared and used as fillers for anti-corrosion coatings to improve the anticorrosion performance of WPU coatings. Their structure were characterized by XRD, FT-IR, Raman, and SEM. Electrochemical tests indicated that the WPU coating containing 0.3 wt% TGO-2 exhibited the highest | Z | 0.01HZ and R t values and possessed the best anticorrosion performance. It was primarily attributed to the excellent physical barrier effect of graphene oxide which was grafted onto polypropylene, improving its dispersibility in coatings.