Study On Self-healing Superhydrophobic F-CNTs/polymer Coating

Due to hierarchical micro/nano-structures and low surface energy,superhydrophobic materials have many valuable applications,such as anti-icing,self-cleaning,and drag-reducting,etc.Superhydrophobic coatings are vulnerable to scratches,abrasions,and solvent corrosion,etc,which impaired superhydrophobicity according to the damage of micro-nanoscale topography and the loss of chemical components.Fabrication of reparable superhydrophobic surfaces can effectively alleviate these problems and expand their service lifespan.In this paper,superhydrophobic materials were prepared by combining fluorinated carbon nanotubes(F-CNTs)with different polymers matrix.(1)Fluorosilane(T-FAS)with tetrabranched structures was synthetized using pentaerythritol tetra(3-mercaptopropionate),dodecafluoroheptyl methacrylate and 3-(trimethoxysilyl)propylmethacrylate at a molar ratio of 1: 3: 3 by click chemistry method.Fluorocarbon chains acted as low surface energy components,and trimethoxysilane group was capable of being grafted onto carbon nanotubes.Obtained F-CNTs showed good long-term storage stability,hydrophobicity and oleophobicity.(2)The superhydrophobic F-CNTs/polyurethane(PU)coatings were prepared with the mixture of F-CNTs and PU via dip-coating.When the content of F-CNTs was 45 %,the water contact angle increased to 152.0 ± 1.2° and the sliding angle decreased to 7.5°.Solvent immersion and Plasma experiments were carried out to investigate self-healing ability of component damage.The result showed that F-CNTs/PU coating revealed obvious repairable performance after solvent immersion and 7 times of Plasma cycles.The tape adhesive,sand abrasion and sand impact tests were used to evaluate the mechanical stability.The results indicated that F-CNTs/PU coating can ramain superhydrophobicity after tape adhesive tests,while F-CNTs/PU coating can restore superhydrophobicity after 130 ? treatment in 10 min.(3)F-CNTs/polydimethylsiloxane(PDMS)superhydrophobic films were prepared via vaccum-assisted assembly-transfer method.When the content of F-CNTs was 6 wt%,the water contact angle increased to 152.0 ± 1.2° and the sliding angle decreased to 7.5°.The repairable performance was evaluated by physical and chemical treatments.The results indicated that F-CNTs/PDMS films can restore superhydrophobicity at room temperature after immersed in acid,alkali,and toluene solvent for 10 h.Besides these,F-CNTs/PDMS films can also remain superhydrophobic after 180 times bending tests.