Construction and Characteristics of the Mechanically Robust Superhydrophobic Wood Surface Based on SiO₂-PDMS Coating

Octadecyltrichlorosilane (OTS) was grafted on the SiO₂ microsphere surface by the methods of Stöber and solution self-assembly. Polydimethylsiloxane (PDMS) and SiO₂ coatings were fabricated on the wood surface by drop-coating method. The micro-topography, chemical composition and surface structures of the SiO₂-PDMS superhydrophobic wood were chartered by the scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The robust superamphiphobic properties was measured and evaluated by water contact angles and roll-off angles, sand abrasion tests. The results show that the -SiO₂-PDMS coating were deposited onto the wood surface, which eventually affected the wettability and the stability of the wood. The as-prepared SiO₂-PDMS superhydrophobic wood does not change the color-texture of wood, but has a low-adhesion superhydrophobic performance, with an contact angle of 158° and roll-off angle of 6°. The robust superhydrophobic performance of the SiO₂-PDMS superhydrophobic wood, indicating that SiO₂-PDMS superhydrophobic wood has good mechanical stability. The resulting surface not only exhibited superhydrophobic property but also had excellent robust performance under sand abrasion tests.