Hexagonal boron nitride/poly(vinyl butyral) composite coatings for corrosion protection of copper

Hexagonal boron nitride (h-BN) fillers are incorporated into poly(vinyl butyral) (PVB) coatings to improve the corrosion protection performance of copper. It has been revealed that the h-BN fillers exhibit an excellent dispersiblility in PVB coating due to the non-covalent interactions between h-BN fillers and the PVB molecules. Electrochemical characterization reveals that the corrosion resistance of the BN-reinforced PVB (BN-P) coating is 5–6 orders of magnitude higher than that of the pristine PVB coating. Photographs and metallography show that the copper substrate beneath the BN-P coating does not suffer from corrosion after immersion for 2 months, indicating that the BN-P coating can provide a long-term protective barrier for the underlying copper substrate. Loading 0-0.25 g h-BN fillers in 2.0 g PVB, the corrosion protection performance increases with increasing the loading of h-BN fillers. The scratch test results suggest that h-BN fillers do not accelerate copper corrosion when the BN-P coating is damaged.