Preparation Of Super-Hydrophobic Surface And Anti-Icing Research By Atmospheric Pressure Plasma Chemical Vapor Deposition

Study of atmospheric pressure plasma technology has gained a quick development in the application. Preparation of super hydrophobic films by atmospheric pressure plasma technology in open environment has many advantages, including simple structure, low cost, low energy consumption, easy operation. The super hydrophobic surface has many special applications, such as self cleaning, anti-corrosion, anti icing. This paper used atmospheric pressure plasma chemical vapor deposition method for preparing superhydrophobic film, and studied the anti icing effect of super hydrophobic thin film at low temperature. This paper mainly includes the following contents:(1)The research background of this paper and a variety of traditional methods of anti icing were introduced. It was pointed out that the super hydrophobic surface was a potential effective method for the prevention of ice coating. The theoretical model and the influencing factors of the super hydrophobic surface were introduced. The "lotus effect" and other nature of the super hydrophobic state were briefly analyzed. It was concluded that the surface micro structure had great influence on the hydrophobic characteristics. The various methods of preparing super hydrophobic surface made brief introduction. And the reason that choosing the atmospheric pressure plasma chemical vapor deposition method prepared super hydrophobic surface made brief explanation.(2)A set of atmospheric pressure plasma chemical vapor deposition device was designed. Plasma jet source was composed of a simple needle tube dielectric barrier discharge structure. The super-hydrophobic films with contact angle over 160° and sliding angle below 3° were successfully prepared by the device. The higher performance super-hydrophobic films could be prepared by decreasing the nozzle-to-sample distance and applied voltage, and increasing monomer flow rate; At the same time, the characteristics of plasma discharge in gas phase deposition were analyzed, the volt-ampere characteristic and the power displayed that the discharge was stable in the deposition process; The radiation spectrum(OES) test showed that hexamethyldisilazane(HMDSN) monomer was cracked and reacted with oxygen in the air under the action of discharge, producing a large number of C-H, C-O and other groups deposited on the surface of the glass substrate; The substrate temperature was tested by thermal imaging instrument, and the results showed that the lower of the glass substrate temperature, the better of the film quality.(3)Surface morphology test showed that the prepared super hydrophobic film had a micro structure with similar micro nano structure of lotus leaf, and had a high roughness(two orders of magnitude compared with the common glass surface). Surface chemical composition test results showed that the super hydrophobic film contained a large number of low surface energy of the hydrophobic group,the film had a very low surface energy.(4)Self cleaning ability is an important performance evaluation criteria of super hydrophobic surface, water droplets in the super hydrophobic surface rolling process could carry away the pollution, to achieve the cleaning effect; At the same time, corrosion protection is another important performance evaluation criteria of the super hydrophobic surface, The experimental results showed that of preparation of super hydrophobic film could effectively prevent acid and alkali corrosive effect, protecting the substrate and achieving anti-corrosion effect.(5)At the end of this paper, based on the preparation of the super hydrophobic surface, the experimental study on the prevention of icing was carried out, finding that the super hydrophobic could effectively extend the static water droplet freezing time under the condition of low temperature. When the glass substrate was slightly inclined, drops of water easily slipped from the super hydrophobic surface under the action of gravity, significantly preventing the formation of surface ice. Further analysis revealed that icing prevention effect of the super hydrophobic surface was directly related to environmental temperature and the humidity. Under the condition of large humidity, the surface was prone to frost, causing the surface gradually froze.