Fabrication of superhydrophobic fiber fabric/epoxy composites coating on aluminum substrate with long-lived wear resistance

Abstract

A superhydrophobic coating with long-lived wear resistance was successfully prepared by integrating the hydrophobization of cotton fiber fabric and the curing of epoxy composites consisting of polyurethane (PU), polyfluoroalkoxy (PFA) and hydrophobic SiO₂ nanoparticles. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) were employed to investigate the chemical compositions and morphologies of the modified cotton fiber fabric and the prepared coating. When the epoxy solution containing 35 wt% PFA and 25 wt% PU, the obtained coating exhibited superhydrophobic behavior with a water contact angle (WCA) of 153.5 ± 1°. Tribological tests indicated that this fiber fabric/epoxy composites coating had stable friction coefficient and excellent wear-resistance under the harsh conditions with the applied load of 2.8 MPa and the sliding velocity of 0.51 m s⁻¹. After 240 000 cycles of abrasion, the coating just showed the decrease in thickness of 80 μm without apparent damage and could retain high hydrophobicity with the WCA of 142°. Simultaneously, the coating was resistant to the acid or alkali solution. This wear-resistant superhydrophobic fiber fabric/epoxy composites coating may be a good candidate for the practical industrial applications under harsh working conditions.