Study On Easily Deicing Weatherability Of Superhydrophobic Materials And Influence Of Surface Parameters On Icing Shear Strength

Icing problem has always been the focus of research in the industry.Icing problems,such as insulator ice-covering flashover,conductor ice-covering waving,and transmission tower toppling,seriously affect the safe and stable operation of power grid,and even cause incalculable economic losses and social impacts.In recent years,superhydrophobic materials have gradually become one of the research hotspots in the industry because of their good contact angle and droplet rolling characteristics.The anti-icing performance of superhydrophobic materials has also become a key issue of concern to researchers.It is of great engineering application value to explore the anti-icing performance of superhydrophobic materials.In this paper,HMDS(hexamethyldisilazane)modified superhydrophobic material was firstly prepared,and its icing shear strength was compared with RTV(room temperature sulfurized silicone rubber).The reduction coefficient of icing shear strength was analyzed theoretically and experimentally(at different freezing time and icing ambient temperature).By comparing the newly prepared fluorine-containing superhydrophobic material with HMDS modified superhydrophobic material,the easily deicing weatherability of the superhydrophobic material was investigated by simulating the harsh environment of power grid operation.Solidliquid contact area ratio and surface energy of two kinds of superhydrophobic materials were calculated theoretically.The effects of solid-liquid contact area ratio,surface energy,contact angle and rolling angle on icing shear strength were analyzed,and the function equation of icing shear strength was obtained by fitting.The main work is as follows:(1)Based on molecular modification method,HMDS modified superhydrophobic materials were prepared,and the surface microstructure and wetting characteristics were analyzed.The reduction coefficient of icing shear strength of HMDS modified superhydrophobic material compared with RTV material was analyzed from the angle of intermolecular electrostatic force.The icing shear strength of the two materials was compared by controlling the freezing time and icing ambient temperature.(2)The fluorine-containing superhydrophobic material was prepared based on molecular modification method.The fluorine-containing superhydrophobic material was compared with HMDS modified superhydrophobic material,and the easily deicing weatherability of the superhydrophobic material was investigated by simulating the harsh environment of power grid operation.The icing shear strength,contact angle and rolling angle of the two superhydrophobic materials were investigated after repeated icing/deicing,long time acid corrosion,long time salt corrosion and high temperature accelerated aging.The experimental results show that the fluorine-containing superhydrophobic material has lower icing shear strength and better easily deicing weatherability.The changes of surface microstructure of the two kinds of superhydrophobic materials were examined by scanning electron microscope.(3)For the two kinds of superhydrophobic materials under normal and harsh conditions,the ratio of solid-liquid contact area at 25.0 ℃ and-6.0 ℃ and surface energy were calculated according to the Cassie equation and the acid-base method.The results show that the fluorinecontaining superhydrophobic material has a lower ratio of solid-liquid contact area and surface energy in any case.The effects of the surface energy and ratio of solid-liquid contact area,contact angle,rolling angle at low and normal temperature on the icing shear strength were analyzed.According to the analysis results,the relationship function between the basic physical and chemical parameters of the material(ratio of solid-liquid contact area at low temperature,surface energy)and the icing shear strength was fitted.