A Dynamically Omniphobic Liquid-Like Coating with High Hardness and Flexibility

Abstract

Antifouling coatings with high hardness, flexibility, and dynamic omniphobicity have important applications in outdoor public facilities, automobiles, ships, flexible touch screens, etc. However, these required properties are difficult to co-exist in a single coating system, limiting the current practical applications of antifouling coatings. Herein, we prepared a fully hydrophobic antifouling coating with a wide range of surface tension liquids, high hardness, and high flexibility. The innovative material design utilizes hyperbranched epoxy resin (HBEP) combined with hexamethylene diisocyanate trimer (HDIT) to form a highly cross-linked hyperbranched oxazolidinone structure, endowing the coating with excellent hardness (8H) and flexibility. Hydrophobic groups from hydroxy-terminated polydimethylsiloxane (HO-PDMS) provide antifouling properties. The resulting coating exhibited excellent anti-graffiti, anti-adhesion, and self-cleaning properties with sliding angles of 8.7° and 1.8° for water (10 μL) and hexadecane (5 μL), respectively. Even after bending and friction aging tests, the coating maintained its excellent liquid repellency and mechanical properties. Furthermore, it exhibits superior thermal and chemical stability as compared to existing coatings. Finally, we expect that this coating would have great potential for providing antifouling properties and protection to substrates in harsh environments.

Keywords: dynamically omniphobic, liquid-like, high hardness, Flexibility, oxazolidinone