Facile Spray-Coating for Fabrication of Superhydrophobic SiO2/PVDF Nanocomposite Coating on Paper Surface

A facile and low-cost superhydrophobic nanocomposite coating on paper surface was fabricated through one-step simply spraying dispersion, using hydrophobic silica nanoparticles as a filter (SiNPs) and polyvinylidene fluoride (PVDF) as a film-forming material. Hydrophobic SiNPs were fabricated via co-hydropholysis and condensation of TEOS and long-chain alkyl silane based on a simple sol-gel process, and the surface chemical structure of SiNPs was characterized by Fourier transform infrared (FTIR) spectra. The wettability and morphology of the coating surface were measured by contact angle (CA) measurement and scanning electron microscope, respectively. The influence of the mass ratio of hydrophobic SiNPs to PVDF (M(SiNPs:PVDF)) on the superhydrophobicity of paper surface was studied. The results showed that when M(SiNPs:PVDF) was 3:1, the water CA was 156.0 ± 1.0° for the nanocomposite coating with micro/nano-hierarchical structure on paper surface. Further, such superhydrophobic nanocomposite coatings on paper surface showed little adhesive property with water. In addition, the prepared superhydrophobic nanocomposite coating could be applied in other substrates, such as wood, aluminum sheet, stainless steel, polytetrafluoroethylene (PTFE), etc.