| Superhydrophobic coatings inspired by nature have been widely used in self-cleaning,oil-water separation,antibacterial,metal corrosion protection and other fields because of their special non-wettability.In recent years,with the deepening of research on superhydrophobic coatings,more and more technologies have been applied in the preparation of superhydrophobic coatings.However,problems such as poor stability still exist,which seriously affect the application in real life.Hollow mesoporous silica nanoparticles(HMSNs)has the advantages of high specific surface area,cavity and easy surface modification.It can be grafted on the surface and stored in the interior with low surface energy substances.In this paper,it is applied to prepare a series of superhydrophobic coatings with good stability and special functions,and the specific work and conclusions are as follows:1.A kind of mesoporous nano-silica with hollow structure was synthesized by self-template method,and the hollow structure was determined by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Nitrogen adsorption and desorption test proved that it has mesoporous structure with a specific surface area of 773.34m2/g.The particle size was measured by the soffware Nano Measurer and the nano-particle potentiometer,which was about 350nm.Fluoride hydrophobicity and antibacterial properties of HMSNs were modified by vacuum method,and F-HMSNs and Q-HMSNs were respectively obtained.The modification of F-HMSNs and Q-HMSNs was proved by infrared spectroscopy,XPS spectrum,thermogravimetric analysis and other tests.Meanwhile,the modification amounts of hydrophobicity and antibacterial substances were quantitatively calculated.2.Based on the heat transfer characteristics of fluoroalkyl chain,hollow mesoporous silica nanoparticles(F-HMSNs)modified by 1H,1H,2H,2H-perfluorooctane triethoxysilane(FAS-13)was mixed with polydimethylsiloxane(PDMS),and self-healing superhydrophobic coating suitable for various substrates was prepared by spraying method.By exploring the preparation conditions of the coating,it was determined that the optimal effect was achieved when the content of F-HMSNs in the coating was 20%.At this time,the water contact angle of the coating was 156.8°,and the sliding angle was 4.5°.A series of tests have proved that the coating has excellent self-cleaning,chemical corrosion resistance and mechanical properties.After being damaged by O2 plasma,the surface of the coating changes from superhydrophobic state to superhydrophilic state.However,after heating at 100℃ for 30min,the superhydrophobic property of the coating can be recovered,and it can still recover after 15 cycles,showing good self-healing ability.3.The antibacterial super-hydrophobic fabric was prepared by dip-coating method with F-HMSNs and Q-HMSNs,and PDMS as adhesive.By exploring the coating preparation conditions,it was determined that when the ratio of F-HMSNs and Q-HMSNs was 4:2,the antibacterial superhydrophobic fabric had the best performance.At this time,the water contact angle of the fabric was 154.3° and the sliding angle was 4.58°.The antibacterial rate against Escherichia coli and Staphylococcus aureus were 99.98%and 99.52%,respectively.At the same time,anti-bacterial fabric has excellent anti-fouling performance,chemical corrosion resistance and universality.The breathable and moisture permeability test proved that the antibacterial fabrics don’t affect normal use.The washability test showed that after 30 times of washing,the water contact angle of the antibacterial superhydrophobic fabric was still greater than 150°,and the sliding angle was less than 10°,and the antibacterial rate against Escherichia coli and Staphylococcus aureus was also greater than 90%,showing good washability.4.The traditional anticorrosive coating and super hydrophobic coating were combined on 6061 aluminum alloy to prepare SiO2/F-HMSNs@EP coating with excellent anti-corrosion ability.The coating was composed of the bottom SiO2@EP coating and the top F-HMSNs@EP coating.Through the investigation of the preparation conditions,it was determined that the best preparation scheme of super-hydrophobic SiO2/F-HMSNS@EP coating was that the content of 20-30 nm SiO2 in the bottom SiO2@EP is 2%,the spraying amount is 2 mL,and the content of F-HMSNs in the top F-HMSNS@EP is 30%.At the time,the water contact angle and sliding angle of the coating were respectively 152.5° and 6.4°.A series of tests showed that the super-hydrophobic coating has good acid-base resistance and mechanical wear resistance.The results of electrochemical tests showed that the protective efficiency of the super-hydrophobic coating is 98.81%,and the protective efficiency can still reach 95%after soaking in 3.5 wt%NaCl solution for 5 days,it still had excellent corrosion resistance. |
