The surface structure of traditional superhydrophobic coatings is composed of a series of micro-nano structure bumps. Long-term friction will make the bumps smooth or even fail, which is the reason for the poor durability of traditional superhydrophobic coatings. How to balance the durability and hydrophobicity is the most important thing in the current research. Insects such as butterflies and moths can fly in the rain in nature, and the insect wings have very good hydrophobic characteristics. Inspired by this, through imitation of the surface structure of butterfly wings in nature, a processing technology combining femtosecond laser with the principle of near-field effect of microspheres was proposed to prepare micro/nano biomimetic structures on the surface of fluorinated silicone resin. When the laser pulse was applied to the silica microspheres, the energy was further concentrated and enhanced due to the near-field effect, resulting in a microporous pattern on the surface of the resin layer. This surface structure mimiced the surface structure of the butterfly wing and achieved air locking, which could lift the droplets more effectively and achieve the effect of superhydrophobicity. To imitate the scale and micro structure characteristics of butterfly wings, a thin film of silica microspheres was grown on the surface of a smooth fluorinated silicone resin with a certain hydrophobic property by the tensile method, and then a femtosecond laser was used to scan the surface of the film, so as to produce a densely arranged nanopore structure. In the experiment, the parameters such as laser power and scanning speed were mainly studied to explore the morphology and hydrophobicity, and the hydrophobic functional durability of the superhydrophobic coating and the bionic micro/nano surface was compared and analyzed. The self-assembly technology can be used to quickly fabricate large-area monolayer microsphere films, while the femtosecond laser has highly controllable parameters, concentrated energy, and the processing technology is very mature, which is an ideal tool for possibility of droplet immersion into micro-nanostructures, thus enabling further increase of hydrophobic stability of dynamic droplet impacts. At the same time, this microporous structure avoids the direct friction and wear of the material surface, which can greatly improve the durability. This biomimetic microporous structure can be combined with the surface microgroove structure in the later stage, which is conducive to the natural slide of the droplet, thus further enhancing its hydrophobicity and expanding its application in the field of drag reduction and preventing ice formation. The experimental results show that the parameters of laser scanning speed and power value have a great effect on the hydrophobic properties of the biomimetic surface. The best hydrophobic properties are obtained when the laser power is 9 mW, the scanning speed is 10 mm/s, and the processing pitch is 10 urn, and the contact angle is more than 150°. In the durability comparison experiment, after 200 to 1 000 times of friction, the decrease of the contact angle of the finished fluoro-silicone resin layer is significantly lower than that of the other two groups of experiments. The results show that the finished fluoro-silicone resin layer has excellent durability. © 2023 Chongqing Wujiu Periodicals Press. All rights reserved.
