Preparation,Structure,Properties,and Application Of Novel Bulk Continuous Superhydrophobic Materials

In recent years,due to the special wettability of superhydrophobic materials,researchers from all over the world have paid much attention to it.This special wettability not only could endow materials with excellent water repellency,but also has great application prospects in the fields of self-cleaning,anti-corrosion,anti-icing,and oil-water separation.However,the hierarchical rough structure and low surface energy component of superhydrophobic materials are very unstable.Generally,under the action of slight shear force,the hierarchical rough structure and low surface energy component are easy to be destroyed,resulting in the loss of superhydrophobicityand the reduction of the service life and practical value of materials.This has become the most serious problem hindering the practical application of superhydrophobic materials,which needs to be solved urgently.Although some researchers have proposed a variety of methods such as adding adhesive layers and introducing healing agents to prolong the service life of superhydrophobic materials,these researcheswere still in two dimensions,which have certainthinking limitations.Therefore,the existing problem has notbeen fundamentally solved.To solve the above-mentioned problem,novel bulk continuous superhydrophobicmaterials with durability and self-repairability were creatively prepared through the rapid and efficient construction of superhydrophobicity on the surface and bulk of materials.These novel materials have broken through some limitations of research thinking reported previously and could be seemed as three-dimensional materials.Herein,six kinds of novel bulk continuous superhydrophobic composite coatings with different characteristics were designed and prepared by the combination of photopolymerization and hydrolytic polycondensationusing four kinds of different organic polymers,including polyvinyl triethoxysilane?PVTES?,polydimethylsiloxane?PDMS?,polyurethane acrylate?PUA?and polyepoxy acrylate?PEA?,and the silica?Si O₂?inorganic filler.The effects of various organic polymers on the structure and properties of bulk continuous superhydrophobic composite coatings were systematically studied.By optimizing the preparation techniques,six kinds of composite coatings exhibitedsuperior superhydrophobic properties.The tape peeling results showed that the rough structure andchemical composition of the composite coating surface were similar to that of the bulk,indicating thatnot only the surface but also the bulk of the composite coating possessed superhydrophobic performances.Thus,these composite coatingsacquired the characteristics of bulk continuous superhydrophobicity.The sandpaper abrasion test showed that the superhydrophobic bulk of the composite coating would appear in the process of abrasion,which benefited for maintaining the superhydrophobic property so that this unique characteristic preventedthe composite coating from losing itssuperhydrophobicity.After etching by the vacuum plasma,the composite coating would lose the superhydrophobicity and even completely convert to asuperhydrophilic state.Taking advantage of the bulk continuous superhydrophobicity,the surface without superhydrophobic property could be removed by sandpaper polishing todisplay its superhydrophobic bulk,and then repair the superhydrophobicity of the composite coating.Thisself-repairableprocedurewasrapid and efficient.This novel material not only prolongs the service life but also improves the application value of superhydrophobic materials,effectively solving the existing problem of superhydrophobic materials.It is of great theoretical and practical significance to propose the new research idea and theoretical foundation for preparing superhydrophobic materials with environmentally friendly,durable,functional,and self-repairable properties.Additionally,based on the research of the bulk continuous superhydrophobic composite coating,the patterned composite coating with superhydrophobicity/superhydrophilicity composite surface was further prepared by an innovative combination of plasma etching and pattern manipulation,and then the application of it in underwater pattern display was studied.The results showed that,based on the underwater light reflection characteristics of superhydrophobic materials,when the patterned composite coatings were illuminated by the light source,various patterns were capable of displaying successfully,maintaining excellent light responsiveness and light sensitivity.This work provides the theoretical foundation and research basis for extending the application fields of superhydrophobic materials in the future,such as in the fields of ocean exploration,underwater transportation,and water surface decoration.