Fabrication Of The Methyl Silicone Resin-based Superhydrophobic Coating And Its Property Study

The superhydrophobic surfaces represented by lotus leaves have attracted much attention due to their excellent performance and potential application value.In some application fields,such as solar panels,windshields,display screens,and optical devices,superhydrophobic surfaces are required to have high transparency.However,the hydrophobicity,transparency,and durability of superhydrophobic surfaces are mutually constrained,which greatly inhibits their practical and long-term use.In this thesis,the preparation of transparent superhydrophobic coatings for solar panels is the research object,and a highly transparent and wear-resistant superhydrophobic coating is prepared with silica nanoparticles as the filling material and resin as the binder and regulator.The main research content is as follows:Fluorinated SiO₂ nanoparticles were prepared by modifying hydrophilic SiO₂nanoparticles with（Heptadecafluoro-1,1,2,2-tetradecyl）trimethoxysilane（FAS-17）,and then mixed with methyl silicone resin（MSR）.γ-Aminopropyl triethoxysilane（KH550）is used as the coupling agent between SiO₂ nanoparticles in the coating and MSR,as well as between the coating and glass substrate.Fluorinated SiO₂-MSR transparent superhydrophobic coating was prepared on glass substrate by spraying method.The optimal ratio of fluorinated SiO₂ nanoparticles to MSR was investigated,and the properties of transparent superhydrophobic coatings were tested under the optimal ratio.The results show that when the mass ratio of fluorinated SiO₂nanoparticles to MSR is 20%,the transparent superhydrophobic coating prepared has a contact angle of 157°,a sliding angle of 5°,and a hardness of HB.It has excellent ultraviolet resistance and self-cleaning performance.Due to the agglomeration of nano SiO₂ particles,the transmittance of the superhydrophobic coating does not exceed 70%,the mechanical durability is poor,and the temperature resistance and chemical stability are also lacking.In order to improve the transparency of the superhydrophobic coating,in this thesis,tetraethyl orthosilicate（TEOS）was used as the raw material,and 1,1,1,3,3,3-hexamethyldisilazane（HMDS）was used as the catalyst and hydrophobic modifier at the same time.Hydrophobic SiO₂ nanoparticles with uniform size and good dispersion were obtained by the St?ber method,and then the transparent superhydrophobic coating was prepared on glass substrate by cross polymerization with MSR.The hydrophobic SiO₂ nanoparticles were characterized by scanning electron microscope（SEM）,X-ray diffraction（XRD）and fourier transform infrared spectrometer（FT-IR）.The influence of St?ber method preparation process and HMDS modifier dosage on the performance of hydrophobic silica sol coating was investigated,and the performance of the coating was tested.When the mass ratio of hydrophobic SiO₂ nanoparticles to MSR is 4:1,the contact angle of the superhydrophobic coating is 159°,the rolling angle is 3°,the hardness is H,and the transmittance is close to 90%.The coating also has a certain degree of resistance to acid,alkali,and salt,with strong resistance to ultraviolet radiation and good self-cleaning performance,but poor mechanical durability.In order to further improve the mechanical durability of the coating,bisphenol A epoxy acrylic resin（EPA）with high transparency,wear resistance and weather resistance was blended with methyl silicone resin（MSR）to prepare a composite resin.M-EPA-0.3 blend resin is selected as the base of the composite superhydrophobic coating,and hydrophobic SiO₂ nanoparticles prepared by the St?ber method are selected as the filling particles.When the content of hydrophobic SiO₂ nanoparticles is2 g,the contact angle of the composite superhydrophobic coating is 160°,the rolling angle is 3°,and the transmittance is more than 90%.Under different wear modes,the water contact angle on the surface of the composite superhydrophobic coating was greater than 150°,with sandpaper friction 45 times,tape peeling 50 times,and water flow impact reaching 5000 g.By measuring the contact angle after immersion in HCl solution with p H=5,5wt%Na OH and 5wt%Na Cl solution for 24 hours,the coating has good chemical stability.After 120 hours of ultraviolet radiation,the contact angle of the composite superhydrophobic coating decreased from 160°to 155°,still exhibiting superhydrophobicity.The superhydrophobic coating can maintain stability at-20℃-500℃,indicating that the composite superhydrophobic coating has excellent thermal stability and UV resistance.In addition,the coating also has excellent self-cleaning performance.This thesis has 57 figures,8 tables,and 119 references.