Preparation of SiO₂ solvent-free nanofluids for modification of commercial corrosion-resistant coatings

The development of a corrosion-resistance surface on a desired industrial coating is a challenge in several industries. In the aerospace industry, it is necessary to modify the corrosion-resistant coating to address the susceptibility of damage during flight for aviation applications. The present study tested three types of commercially available corrosion-resistant coatings for aviation, and the coating with the best overall performance was modified to enhance its mechanical properties to prevent coating damage due to impacts from raindrops and sand during flight. Silica (SiO₂) nanoparticles with an approximate particle size of 50 nm were prepared by the sol-gel method using tetraethyl orthosilicate (TEOS). The KH560 silane coupling agent, as the neck layer and the M2070 polyether amine as the crown layer, were covalently bonded and then grafted onto the surface of the nano-SiO₂ core to obtain a core-shell structure of the SiO₂ solvent-free nanofluid (SiO₂@KH560-M2070). The tensile property of the polyurethane coating was improved when a small amount of the SiO₂ solvent-free nanofluid was incorporated into the coating. The present study has theoretical and practical guiding significance for the selection and spraying of existing aircraft radome coatings.