Fabrication of transparent and durable superhydrophobic polysiloxane/SiO2 coating on the wood surface

The bionic-superhydrophobic surface is widely used in the field of wood protection. In this work, a novel room temperature vulcanized silicone rubber (RTVSR) superhydrophobic coating was fabricated onto the wood surface with the aid of SiO2 nanoparticles. The RTVSR/SiO2 superhydrophobic coating was composed of poly(methylhydrogens)siloxane (PMHS), vinyl-terminated polydimethylsiloxane (Vi-PDMS) and SiO2 nanoparticles, in which PMHS and Vi-PDMS reacted with each other to form a continuous phase and SiO2 nanoparticles increased the roughness of the coatings on wood surface. PMHS played the key role in assembly of rough surface and hence the fabrication of stable superhydrophobic surface. The formation mechanism of RTVSR/SiO2 superhydrophobic coating was discussed in detail. As a result, the modified wood had a water contact angle (WCA) of 164.4° and a sliding angle (SA) of 5°. Moreover, the super-hydrophobic coating on the surface of wood has excellent resistance to both high and low temperature, UV radiation, water impact and possesses self-cleaning property. The water absorption rate decreased obviously from 45.9 to 28.1% after depositing RTVSR/SiO2 superhydrophobic coating on wood. RTVSR/SiO2 superhydrophobic coating will find a great application in protection of hydroxyl-containing substrates, especially wood, in outdoor environment.