Superhydrophobic Hexadecyltrimethoxysilane-Modified Fumed Silica Nanostructure/Poly(butyl methacrylate) Composite Thin Films via Aerosol-Assisted Deposition: Implications for Self-Cleaning Surfaces

Superhydrophobic coatings with their unique nanostructured surface properties have application in many industrially important technologies but are currently dominated by environmentally problematic fluorinated compounds. Here, we demonstrate the fabrication of fluorocarbon-free superhydrophobic coatings consisting of poly(butyl methacrylate) (PBMA) and nanostructured hexadecyltrimethoxysilane (HDTMS)-functionalized fumed SiO2/PBMA as self-cleaning surfaces via a facile ambient pressure aerosol deposition route. X-ray photoelectron and infrared spectroscopy measurements showed successful composite formation. The deposition temperature and HDTMS-SiO2:PBMA ratio was optimized to give films that had a water contact angle as high as 161 ± 1° and a sliding angle of 1°, owing to a hierarchical surface nano- and microstructure and a root-mean-square surface roughness of 592 nm. This work shows a high-throughput single-step route to environmentally friendly PBMA-based superhydrophobic coatings.