Facile Preparation of Water-Dispersible Graphene Sheets Stabilized by Carboxylated Oligoanilines and Their Anticorrosion Coatings

Dispersion of graphene in solvents is of crucial importance toward its practical applications. In this study, using a water-soluble carboxylated aniline trimer derivative (CAT–) as a stabilizer, the commercial graphene can be stably dispersed in water at high concentration (>1 mg/mL) via strong π–π interaction that was proved by Raman and UV–vis spectra. Moreover, the CAT–-functionalized graphene sheets (G-CAT– hybrid) exhibited high conductivity (∼1.5 S/cm), good electroactivity and improved electrochemical stability. The addition of well-dispersed graphene into waterborne epoxy system (G-CAT–/epoxy) remarkably improved corrosion protection compared with pure waterborne epoxy coating, based on a series of electrochemical measurements performed under 3.5% NaCl solution. This significantly enhanced anticorrosion performance is mainly due to the improved water barrier properties derived from highly dispersed graphene nanosheets in the epoxy coating.