Fabrication of robust and room-temperature curable superhydrophobic composite coatings with breathable and anti-icing performance

Abstract

Superhydrophobic surfaces show great application prospects in various fields, yet the tedious preparation process, sophisticated equipment, and poor durability restrict their large-scale practical applications. In this study, we proposed a simple and efficient approach to fabricating room-temperature curable superhydrophobic composite coatings by spraying the suspension composed of fluorinated silicon-based acrylic copolymer (FSC), amino-terminated polydimethylsiloxane (PDMS) and fluorinated SiO2 nanoparticles (SiO2-F) on various substrates. Due to the special molecular design, our prepared coatings can be cured at room temperature. The resultant FSC15/PDMS/SiO2-F nanocomposite coating containing 40 wt% SiO2-F exhibited excellent superhydrophobicity with a high WCA of 160.4° and a low SA of 1.5°. The prepared coating also displayed satisfactory breathability, preventing structural degradation of the superhydrophobic coatings used in architecture. More impressively, the composite coating can sustain its superior water repellency even after being subjected to harsh mechanical durability damage, including sandpaper abrasion, water dripping, tape peeling tests, and rigorous working conditions, such as corrosive liquid environment, UV illumination, extreme temperatures, and ultrahigh humidity. Besides, the water-freezing time on the coated concrete sample can be postponed to 1860 s at −15 ℃, and the ice adhesion strength was reduced to 56.7 kPa. The facility and universality of the composite coating ensured that it could be applied on diverse material surfaces, including ceramics, tinplate, wood, glass, sponge, fabric filter paper, and cotton, which indicates the potential for large-scale application in industry.