Superhydrophobic coatings have broad application prospects in various fields such as life, industry, and national defense due to their special wetting properties. Especially the promotion of waterproof chips and waterproof glass has made people growing aware of the importance of superhydrophobic coatings. And through years of in-depth research and exploration of superhydrophobic coatings, the functions of the superhydrophobic coatings have become increasingly extensive, and they haves gradually developed into multifunctional coatings with self-cleaning, anti-fogging, antibacterial, anti-icing, flame retardant, electromagnetic shielding, conductive and other properties. As the application fields of superhydrophobic coatings become wider, the role they can play in the future will also increase. However, in current life and production, superhydrophobic coatings have not yet been widely used. The main reason is that the superhydrophobic coatings prepared by most current methods are fragile, poorly durable and difficult to repair. Through in-depth research on superhydrophobic coatings and their durability, it is found that the main factors for superhydrophobic properties of coatings are the surface micro-nano rough structure and the low surface energy. The rougher the micro-nano structure and the lower the surface energy, the stronger the hydrophobicity of the coating. However, the micro-nano rough structure and low surface energy materials are very fragile. The micro-nano rough structure on the surface is easily to be destroyed by some mechanical external forces such as mechanical wear, object collision, sharp tool cutting, water impact, peeling, etc. Substances with low surface energy will also decompose and age due to ultraviolet radiation, high temperature, acid-base corrosion, electrochemical corrosion, etc. Both of these situations will cause the superhydrophobic coating to lose its hydrophobicity. To better solve this problem, this paper studied the coating's characteristics including wear resistance, adhesion, toughness, hardness, heat resistance, frost resistance, acid and alkali corrosion resistance, electrochemical corrosion resistance, pollution resistance and UV resistance. For each durability type, a variety of test methods were summarized, the control parameters corresponding to each test method were explained in detail. Detailed examples of different durability types and test methods were also given. This paper also summarized two types of methods to improve surface durability for the problem of poor durability of superhydrophobic coatings. one was to improve the mechanical stability of the superhydrophobic coating and the other was to give the coating a good self-healing ability. The methods to improve the mechanical durability of the coating included constructing a multi-level hierarchy, improving the bonding ability between the coating and the substrate, constructing a self-similar superhydrophobic surface and establishing an "armor" structure, etc. Self-healing ability included self-healing of rough structure, self-healing of low surface energy materials and overall self-healing. With strong mechanical stability, the superhydrophobic coatings have better resistance to damage, and with good self-healing ability, it can ensure that the coatings can still return to the superhydrophobic state after being damaged. Finally, the future development of superhydrophobic coatings is prospected: find a low-cost, mass-producible superhydrophobic surface preparation method that meets various durability requirements. © 2023 Chongqing Wujiu Periodicals Press. All rights reserved.
