Tribological and anticorrosion properties of polyvinyl butyral (PVB) coating reinforced with phenol formaldehyde resin (PF)

A series of environmental-friendly polyvinyl butyral/phenol formaldehyde resin (PVB/PF) composite coatings with various PF contents were prepared by solution blending method. The tribological and anticorrosion properties of composite coatings as well as the influence of PF content were systemically studied. The results showed that the addition of PF can significantly improve the wear resistance of the PVB coating, with the minimum wear track width being reduced from 301 μm (pure PVB coating) to 154 μm (PVB/PF composite coating) under dry friction condition. Besides, electrochemical impedance spectroscopy (EIS) results showed that the corrosion resistance of the composite coatings can also be significantly improved after immersing in 3.5 wt% NaCl aqueous solution for 30 days. The impedance modulus at low frequency (│Z│_0.01Hz) of 30 wt% PF reinforced composite coating is 2.41 × 10⁷ Ω cm² after immersed for 30 days, which is three orders of magnitude higher than that of pure PVB coating. The good tribological and anticorrosion properties of composite coating can ascribe to the uniform and dense structure formed by PVB and PF, which has good flexibility, high mechanical strength and excellent barrier properties.