Super hydrophobic coating and oil-water separation based on modified titanium dioxide and glycerol ethers

Abstract

At present, the super hydrophobic surface is mostly constructed with siloxane colloid and fluoropolymer. The super hydrophobic surface can be broken by fine friction, and its acid-base resistance is poor. In this paper, firstly titanium dioxide (TiO2@GDE) was modified by ethylene glycol diglycyl ether (GDE). TiO2@GDE was mixed with dodecanoic acid (DA), perfluorodecyl triethoxysilane (PFTS) and GDE to make super hydrophobic mixture. By soaking in this mixture, the super hydrophobic surface of cotton cloth (SHC) was obtained. Among them, GDE is used as a cross-linking agent to cross-link PFTS, DA, TiO2@GDE and facial surface. PFTS and DA are used to reduce the surface energy, and TiO2@GDE is used to improve the surface roughness of cotton cloth. Secondly, the effects of construction condition parameters on the water contact angle and water rolling angle of SHC were explored. The results showed that the optimal mixture concentration was 20g/L, soaking time was 30min, drying temperature was 100oC, and drying time was 2h. Under the optimal conditions, the surface water contact angle (WCA) of the modified cotton cloth is 164±3o, and the water rolling angle is 9±3o. Finally, the obtained SHC is used for oil-water separation. Whether trichloromethane, or n-hexane and dichloromethane, separation efficiency can reach more than 99%. Whether it is the next oil-water separation directly after the completion of the last oil-water separation without drying, or the next oil-water separation after the completion of the last oil-water separation after drying, more than 10 times of oil-water separation can be carried out, and the separation efficiency can reach more than 98%. In addition, the self-cleaning property, durability, friction resistance and acid/alkali resistance of the SHC were tested, and the results were good. At the same time, the whiteness, thickness, gloss and CIELAB color are tested. The results show that the super hydrophobic coating constructed has little change in the physical properties of cotton cloth.