Design,Preparation And Performance Evaluation Of Self-healing Superhydrophobic Materials

Superhydrophobic materials have unique wettability,and have broad application prospects in many fields such as self-cleaning and oil-water separation,which has attracted wide attention.However,when the superhydrophobic material is subjected to external impact or chemical damage,it is easy to lose the superhydrophobic performance,and the durability problem seriously hinders the application of superhydrophobic materials in practical situations.In this paper,three kinds of self-healing superhydrophobic coatings were prepared by combining self-healing and superhydrophobicity,and they were committed to the functional application of coatings,which could provide a new scheme for durable superhydrophobic materials.The following three tasks are specifically studied:(1)In this study,multi-walled carbon nanotubes(MWCNT)and micron carbon powder were deposited on the substrate with self-healing performance to construct a micro-nano rough structure,and a self-healing superhydrophobic coating with photothermal/electrothermal dual deicing performance was prepared.When the coating is scratched,the dynamic bond inside the substrate will migrate to promote the self-healing of the coating,and at the same time drive the surface superhydrophobic particles to move to the damage site,so as to restore the superhydrophobic performance.It should be noted that the entire self-repair process does not require external stimulation and can be completed at room temperature.In addition,due to the existence of MWCNT,the coating has good electrical conductivity and photothermal conversion performance,which makes the coating have the performance of photothermal/electrothermal double de-icing,and the de-icing efficiency is greatly improved.Moreover,the coating also has excellent wear resistance,and it still has superhydrophobicity after being worn on commercial sandpaper for 16 m with 500 g weight.(2)In this study,an efficient photothermal deicing and self-healing superhydrophobic coating was prepared by"semi-embedding"the candle ash on the self-healing substrate.Because the candle ash exhibits excellent light-to-heat conversion performance,it can melt a 5mm thick ice layer in a short time,and after repeated icing/deicing experiments,it can still maintain super-hydrophobic performance,indicating that the coating has good properties mechanical stability.In addition,the coating is simple to prepare,low in cost,and has stable self-cleaning and antifouling capabilities.(3)In this study,a self-healing superhydrophobic anti-corrosion coating was prepared by depositing nano-Si O₂ particles on the surface of the self-healing substrate.This coating has shown good anti-corrosion performance in 3.5 wt%Na Cl solution,PH=1 HCl solution and PH=13 Na OH solution.This is because the superhydrophobic coating effectively prevents the anticorrosive liquid from contacting with metal materials.when the coating is damaged,the material self-heals and restores the super-hydrophobic performance,thereby repairing the anti-corrosion performance and effectively extending the service life of the material.The coating showed excellent mechanical stability in both abrasion resistance experiment and tape sticking experiment.At the same time,the coating showed good chemical stability,indicating that the coating has good practical value.