Mussel-inspired hydrophobic modification of boron nitride nanosheets to enhance the dispersion and anticorrosive performance in polymeric coatings

Boron nitride nanosheets (BNNSs), a two-dimensional (2D) insulator material with outstanding barrier properties, are prone to aggregation owing to π-π interaction, which limits their use in heavy anti-corrosive coatings. In this work, urushiol (Ur), a cheap and easily available natural compound, was employed to modify BNNSs via interacting catechol groups of Ur with the surface of BNNSs inspired by mussel, which was proved by UV–vis, Raman, FTIR, and XPS. Synthesized [email protected] exhibited high hydrophobicity and dispersibility in solvents and epoxy coatings (EP), which enhanced the compatibility between the BNNSs and matrix. Electrochemical impedance spectroscopy (EIS) clearly manifested that the impedance at low frequency (|Z|f = 0.01 Hz) of the polymeric coating containing 0.75 wt% [email protected] was about two orders of magnitude higher than that of pure EP coating immersed in 3.5 wt% NaCl solution for 50 days. Characterization of corrosion products also evidenced that the modified BNNSs significantly enhanced the anticorrosive resistance of EP coatings via the improved barrier performance and corrosion inhibition effect of Ur, which is supposed to be extensively used as nano-reinforcing fillers in the field of corrosion protection.