Preparation of robust fluorine-free superhydrophobic coating using fly ash and its self-cleaning, anti-icing and anti-corrosion properties
Weitao Song, Huiping Song, Zhenlian Fan, Shuyan Cheng, Zhengjun Feng
Abstract
Superhydrophobic coatings have attracted extensive interest from researchers in recent years. An important future development direction involves utilizing zero-cost solid waste materials as structural components to create superhydrophobic coatings. In this article, fly ash(FA), a common solid waste, was used as the main material, epoxy resin (ER) and polydimethylsiloxane (PDMS) were used as the main film-forming substances. A multifunctional FA-superhydrophobic coating ER/FA@PDMS/SiO 2 was prepared by spraying method. FA-superhydrophobic coating exhibited a water contact angle (WCA) of 156.4° ± 0.8° and water sliding angle (WSA) of 4.5° ± 0.1°. ER/FA primer has an irregular porous structure, and the PDMS/SiO 2 penetrate into the porous structure. The porous ER/FA coating can store PDMS and SiO 2 , and the FA superhydrophobic coating has similar rough structure and low surface energy inside and on the surface. FA-superhydrophobic coating have strong mechanical stability, after the surface coating is destroyed, the internal structure of the coating can still maintain excellent performance. The corrosion current density of FA-superhydrophobic coating is about 9.392 × 10 −7 A/cm 2 , which is one order of magnitude lower than ER/FA coating. FA-superhydrophobic coating can delay icing by about 121.55 % under extremely cold conditions. This simple and low-cost superhydrophobic coating has great application value in self-cleaning, anti-icing and anti-corrosion.