Performance Study And Preparation Of Fluorine-Free Transparent Wear-Resistant Superhydrophobic Surface

The superhydrophobic surface prepared by various methods has broad application prospects in various fields,including high transparent superhydrophobic coatings applied to the surface of optical devices and multifunctional superhydrophobic sponges for oil-water separation.However,the applications of artificial superhydrophobic coatings on large-scale are still limited due to poor transparency,poor durability,substrate dependence and high costs.As for oil-water separation,superhydrophobic sponges have a relatively single function,which limits the range of applications of oil-water separation sponges in production and life.This paper attempts to solve the above problems with simple way,mainly including the following two aspects:First:High transparency,excellent durability and simple preparation process are the three main factors for practical application of superhydrophobic coatings.Herein,we prepared a superhydrophobic?SH?suspension composed of hydrophobic SiO₂ nanoparticles?about 10 nm?and fluorine-free resin.The superhydrophobic suspension was used to fabricate an SH coating with high transparency and durability via a simple spraying process.We found that the microscopic surface topography,water contact angle?WCA?and transmittance of the coating strongly depends on the ratio of the resin to nanoparticles.The optimum coating had a static WCA of 160°,a sliding angle?SA?less than 3°and a contact angle hysteresis?CAH?less than 8°.The average transmissivity of the coated glass in the visible light range?400-800 nm?reached 91.03%.Meanwhile,the coating has high impalement resistant and excellent flexibility?bending radius of 3.0 mm?.Simple spraying process and room temperature curable coating could be applied to various substrates and large-scale production.In addition,the coating can repel various mixed liquids and has good antifouling ability.These rapidly constructed coatings,without complicated modification and reaction may offer potential benefits for the fabrication of large-area,robust,superhydrophobic and self-cleaning surfaces.Second:The development of new multifunctional adsorbent sponge with superhydrophobicity,magnetic response,flame retardancy and efficient adsorption of high viscosity oils reveals attractive prospect for oil-water separation.In this work,the Fe₃O₄ nanoparticles with photothermal effect and magnetism were used to achieve solar-assisted efficient adsorption of high-viscosity oil and controlled magnetic drive adsorption and recovery.Using intrinsic flame-retardant melamine-formaldehyde?MF?sponge as the skeleton,the Fe₃O₄/PDMS coating successfully modified superhydrophilic sponges into superhydrophobic?WCA=158°?and superoleophilic?OCA=0°?sponges with excellent flame retardancy.Thanks to the low density,high porosity,chemical and mechanical stability,the prepared superhydrophobic sponge exhibits excellent oil and organic solvent adsorption properties and reusability.Owing to the excellent photothermal performance of Fe₃O₄/PDMS@MF sponge,the sponge was heated quickly with solar-assisted and reduced the viscosity of the high-viscosity oil,which enabled the high-viscosity oil was absorbed efficiently.At the same time,the Fe₃O₄/PDMS@MF sponge can be controlled by remote magnetic field and enters the special oil pollution area for oil adsorption and recovery.This superhydrophobic multifunctional sponge has great potential for high-viscosity oil adsorption,magnetic drive recovery and flame-retardant applications.