Robust fluorine-free superhydrophobic coating on polyester fabrics by spraying commercial adhesive and hydrophobic fumed SiO2 nanoparticles

Superhydrophobic (SH) surfaces generally have weak mechanical stability which has seriously restricted their practical application. In this work, SH coatings with robust mechanical stability were prepared on polyester fabric by the orderly spraying of commercial adhesives and a suspension of fluoride-free hydrophobic fume SiO2 nanoparticles (NPs). A series of tests, including dry abrasion, hand-rubbing, tape peeling, knife-scratching, wet abrasion, brush washing, ultrasonic cleaning, and rotate-washing, all demonstrate that the as-prepared SH coatings have excellent mechanical stability. The strong adhesion between the SBR adhesive layer and fabric, as well as the adhesion between the substrate and hydrophobic SiO2 NPs, is most likely responsible for the excellent mechanical performance. The elastic property of the SBR adhesive layer absorbs friction energy, contributing to the coating's mechanical property. Furthermore, the SH surfaces have anti-fouling properties against slurry impacts from various heights and many types of liquids; the surfaces were not affected after 100 h immersion in simulated perspiration. We believe that such fluorine-free and robust SH coatings can be used in outdoor wear-resistant products, such as backpacks, shoes, etc.