| Nature has many biological structures with a waterproof phenomenon,which exhibits the super-hydrophobicity observed in various plants,insects and animals.Through biological design,the process of replicating adaptability and deriving from various natural environments is called"bionic creature".The development of a wide range of biomimetic organisms provides space for the development and manufacture of superhydrophobic surfaces.Surfaces with high apparent contact angle?>150°?and low contact angle hysteresis?<10°?are generally called superhydrophobic surfaces.There are two factors for the formation of superhydrophobicity.One is to use chemical modification to reduce the surface energy of the coating,and the low surface energy of the coating is used to reduce the adhesion of water;the second is to form a bionic structure such as a lotus leaf structure,etc.The effective area between the two,so as to achieve structural super-hydrophobic.These two factors are indispensable.In this paper,the two parts are developed,and both parts are formed by electrostatic adsorption to form a raspberry structure.The structure is hydrophobic by phase separation,and then the coating is modified with a silane coupling agent to meet the requirements of superhydrophobicity..The full text is divided into four chapters.The first chapter is a literature review.It briefly introduces the concept and mechanism of superhydrophobicity and the phenomenon of superhydrophobicity in nature.It highlights the current scientific research on the construction of super-hydrophobic coatings for the construction of double-sized raspberry structures,and explains Raspberry-like super-hydrophobic composite coatings are proposed.The second chapter mainly discusses the preparation method of super-hydrophobic polymethyl methacrylate coating by phase separation to construct raspberry structure.It is proposed that the raspberry structure is formed by electrostatic adsorption,and the existence of raspberry morphology can be directly observed by transmission electron microscopy?TEM?,and infrared spectroscopy?FT-IR?proves that SiO2 is enriched in polymethyl methacrylate microspheres PMMA)surface,which can prove the formation of raspberry structure?PMMA/SiO2?.The coating was formed by the knife coating method,the morphology of the coating was observed by a scanning electron microscope?SEM?and the static contact angle?CA?of the coating was measured using a contact angle measuring instrument to judge the surface wettability of the coating.Adjust the content and particle size of SiO2 to get the best hydrophobic coating.Using heptafluorodecyltrimethoxysilane to hydrophobize the prepared coating,thereby reducing the surface polarity of the coating,the static contact angle of the modified coating is 152.6°,the contact angle hysteresis is 4°Super hydrophobic performance meets the requirements of super hydrophobic.The third chapter is mainly to further improve the experiment,and the superhydrophobiceffect ofthe coatingisimproved.Using methacryloyloxyethyltrimethylammonium chloride?DMC?as cationic comonomer and divinylbenzene?DVB?as crosslinking agent,crosslinked monodisperse positively charged polystyrene was prepared by dispersion polymerization?PS?particles with a particle size of 900 nm.Through electrostatic adsorption and negatively charged silica?SiO2?to form polystyrene-silica?PS/SiO2?composite microspheres with raspberry structure to improve the roughness of the surface.The effects of SiO2 content and particle size changes on the structure and surface hydrophobic properties of raspberry particles were also explored.The hydrophobic coating was prepared by pulling the film,and the film was hydrophobized with heptafluorodecyltrimethoxysilane.After surface modification,the maximum static contact angle of the hydrophobic film was 158.1°.Contact The angular hysteresis is3°.The fourth chapter is a summary of the full text,that is,a systematic summary of the preparation of super-hydrophobic coating by constructing raspberry structure through phase separation. |
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