Dip-Coating Method of Preparation of a Silicon-Modified Acrylic Resin Hydrophobic Coating with Corrosion Resistance for Copper–Aluminum Composite

A fluorine-free environmentally friendly hydrophobic corrosion-resisting coating was synthesised by the cross-linking reaction of silicone, nano-SiO₂ modified acrylic resin and N3390. The coating was dip-coated on the surface of copper–aluminum composite. The morphology of the coating was characterised by SEM and AFM, the composition by EDS, XPS and FT-IR, and the mechanical properties and corrosion resistance by a sand impact test and a neutral salt spray accelerated test. The properties of the coating were characterised by electrochemical testing, water contact angle (WCA) and weight loss data. The results showed that the coating substrate was uniform and compact. The Si-O-Si structure in the coating the stability and the nano-SiO₂ particles structure improved the hydrophobicity of the coating (average WCA was 103.7°). The corrosion resistance of the coating was excellent in the atmospheric environment, and the corrosion inhibition efficiency of copper–aluminum composite was up to 98%.