Study On Preparation And Properties Of Inorganic/Organic Composite Superhydrophobic Wear-resistant Coatings

Superhydrophobic surface is a special functional material surface which contact angle is greater than 150°and sliding angle is less than 10°.In recent years,the preparation of wear-resistant superhydrophobic coatings has become one of the major trends in the superhydrophobic areas.By controlling the chemical composition and surface morphology of the material surface and introducing the binder,a superhydrophobic coating with excellent wear-resistant can be successfully prepared.In this paper,by a simple spray process,a superhydrophobic VTMS/SiO₂/UPR coating,a superhydrophobic APMS/SiO₂/ER coating and a superhydrophobic TiO₂/ER coating were prepared with SiO₂ and TiO₂ used as raw materials.The contact angle?CA?and sliding angle?SA?of the coating surface was tested by a contact angle tester.The surface morphology of the coating was observed with a scanning electron microscope?SEM?.The chemical composition of nanoparticles by Fourier Transform Infrared Spectroscopy?FT-IR?.The stability of the coatings and grafting density of modifier were investigated using a thermal gravimetric?TGA?.The abrasion resistance of the coatings was examined by rubbing of sandpapers.The details are as follows:?1?After mixing nano-silica?SiO₂?particles modified with vinyltrimethoxysilane?VTMS?and ethyl acetate solution of unsaturated resin?UPR?,the superhydrophobic coatings with micro-nano rough structures were successfully prepared by spraying process.The experiment results show that the greater particle size of the modified SiO₂,the better hydrophobicity of the coatings within the particle sizes range of the study,and when the average particle size reaches 170 nm,the coatings begin to have superhydrophobicity.When the mass ratio of modified SiO₂/UPR is between 5:5 and 5:3,the coatings can be made superhydrophobic.Under the same mass ratio of modified SiO₂/UPR,the hydrophobicity of the coating has been reduced when friction times increased.At the same time,the higher mass ratio of modified SiO₂/UPR,the more obvious the declining tendency of the superhydrophobicity coatings.?2?Aftermixingthenano-silica?SiO₂?particlesmodifiedwith aminopropyltrimethoxysilane?APMS?and the ethanol solution of epoxy resin?ER?,the hydrophobic coatings with micro-nano rough structures was prepared by spraying process.And finally embellished by octyltrimethoxysilane to obtain superhydrophobicity.The experiment results show that the better hydrophobicity of the coatings within the particle sizes range of the study,and when the average particle size reaches 57 nm,the coatings begin to have superhydrophobicity.When the mass ratio of modified SiO₂/ER is between4:5 and 5:3,the coatings can be made superhydrophobic.Under the same mass ratio of modified Si O₂/ER,the hydrophobicity of the coatings has been reduced when friction times increased.At the same time,the higher mass ratio of modified SiO₂/ER,the more obvious the declining tendency of the superhydrophobicity coatings.?3?After mixing nano-titania?TiO₂?particles prepared by hydrothermal method and the ethanol solution of epoxy resin?ER?,the hydrophobic coatings with micro-nano rough structures were successfully prepared by spraying process.And finally embellished by dichlorodiethylsilane to obtain superhydrophobicity.The experimental results show that with the increase of the average particle size of TiO₂,the hydrophobicity of the coatings increase in the particle size range of study.When the average particle size reaches about50nm,the coating begins to have superhydrophobicity.When the mass ratio of TiO₂/ER is between 4:4 and 4:3,the coating can achieve superhydrophobicity,and the contact angle of coatings reaches a maximum of 153.5°at the mass ratio of 4:4.The coating needs to be immersed in ethanol for at least 3.5 min to obtain superhydrophobicitythe coating is in ethanol.The hydrophobicity of coatings has been reduced when friction times increased.Due to the photosensitivity of TiO₂,the conversion between superhydrophobicity and hydrophilicity of coatings will be occurred under UV.?4?In this paper,three superhydrophobic coatings all have good self-cleaning properties under simulated contamination.After the anti-corrosion electrochemical study in 3.5%sodium chloride solution,three superhydrophobic coatings all show good corrosion resistance.Three superhydrophobic coatings have hydrophobic properties for various droplets of solvent,but have lipophilic properties for oily substances by examining the hydrophobicity of different droplets on the three superhydrophobic coatings.So the superhydrophobic coatings have a great application prospect in oil-water separation.