Effect of Lubricant Viscosity on Dynamic Water Repellency and Durability of Lubricated Surfaces

Transmission lines icing has seriously threatened the safe operation of power grid. Slippery lubricant-infused porous surface (SLIPS) exhibits excellent antiicing performance, which is a potential candidate in anti-icing field for power transmission lines. However, different lubricant viscosities make the SLIPS exhibit different properties. Herein, the SLIPSs with different silicone oil viscosities were prepared to study the effect of viscosity on the dynamic water repellency and durability of the SLIPSs. The low-viscosity lubricant facilitates the droplet to bounce on the surface, and the droplet slides fast on the inclined surface. Especially, when the viscosity was 20 cSt, the droplet presented superhydrophobic-like bounce on the surface. Additionally, the increase of lubricant viscosity reduces the evaporation loss of SLIPS and improve the lubricant retention rate. When the viscosity was 1000 cSt, most of the lubricant film on the surface still existed after 35 days, and the lubricant retention rate was as high as 69%. Therefore, the low lubricant viscosity enhances the dynamic water repellency of the SLIPS, and high lubricant viscosity is beneficial to the durability of the SLIPS. In practical anti-icing application of lubricated surfaces, the dynamic water repellency and durability of SLIPS should be considered when selecting the lubricant viscosity.