| The superhydrophobic surface is a special non-wetting surface,specifically a surface with a contact angle of more than 150° and a roll angle of less than 10°.In addition to its excellent water-repellent and waterproof function,it also has good self-cleaning,corrosion-resistance,and anti-icing properties,it has a wide application prospect.However,due to the complex preparation methods of artificial superhydrophobic surfaces,the high cost of preparation,and the most important point,the poor surface mechanical properties which lead to poor durability,resulting in the superhydrophobic surface is still limited to theoretical research,and has not been applied to real life.Therefore,it is necessary to find a simple and economical method for preparing superhydrophobic surfaces and to improve the mechanical properties of superhydrophobic surfaces.In this paper,some animals and plants with superhydrophobicity in nature,and the preparation methods and properties of superhydrophobic surfaces are introduced.The existing methods for improving the mechanical properties of superhydrophobic surfaces are briefly reviewed.Based on the research above,two new types of superhydrophobic surfaces are prepared,and their various properties are studied respectively in this study.Then two methods to improve their mechanical properties are proposed,and the feasibility of these two methods is verified by experiments.The main conclusions are as follows:(1)An immersion method was successfully used to prepare a robust micro-nanoscale flowerlike ZnO/ER superhydrophobic coating,the wettability test result shows that the water contact angle is 155 ± 2° and a sliding angle is less than 2°.A series of surface properties tests on super-hydrophobic surfaces show that the coating can be used on the surface of various common substrate materials such as glass,metal,and cloth.It maintains superhydrophobicity with temperatures ranging from 20 to 80 ℃ and over a pH range of 1-11.(2)The repeatability tests results of superhydrophobic surface shows that it loses superhydrophobicity after the friction process,but after using the retreatment process,the failure surface recovers the superhydrophobicity very well again.Then propose a method to improve the durability of superhydrophobic coatings:reuse the coating surface.This method is suitable for the surface of superhydrophobic coatings with simple and rapid preparation methods and strong mechanical properties of the coating itself.(3)The friction tests results of superhydrophobic surface shows:increasing the substrate roughness can improve the wear resistance of the superhydrophobic coating;and as the roughness of the substrate increases,the wear resistance of the superhydrophobic coating first increases and then decreases.Then,a method for improving the mechanical properties of the superhydrophobic coating is proposed:increasing the substrate roughness.The method is applicable to all superhydrophobic coatings and can be applied to other various base materials such as metal,wood and so on.(4)A new method for the preparation of superhydrophobic aluminum surface by the combination of drop-etching and high temperature soaking is proposed.The superhydrophobic aluminum surface has a contact angle above 156° and a sliding angle less than 2°.A series of surface properties tests on superhydrophobic surfaces show that the method proposed in this study for preparing superhydrophobic aluminum surfaces can ensure the integrity of the material.The superhydrophobic aluminum samples could maintain superhydrophobicity at temperatures ranging from 100 to 180 ℃,and it has good anticorrosion ability and antifouling ability.The mechanical performance verification test results show that the durability of the superhydrophobic aluminum surface can be improved by recycle,but the method of increasing the substrate roughness cannot improve the wear resistance. |
