The Research Of Self-cleaning Fluorocarbon Coating

In recent years, fluorocarbon coating are widely used in many aeras such as agriculture, industry and national defense, etc. beause of their high corrosion-resisting, solvent resistance and abrasion resistance characteristics. Although the fluorocarbon coating have low surface energy and large contact angle, it still does not have self-cleaning characteristic,. This text reported the method to develop the self-cleaning fluorocarbon coating, which based on the super-spot and super-hydrophobic theories. The main research contents and conclusions are as follows:1. The TiO2sol、SiO2sol/TiO2sol and SiO2sol/TiO2sol are treated by microwave for4h, the as-prepared sol was characterized by XPS、XRD and UV-vis and its photocatalytic performance was investigated. And the experimental results show that after treating by microwave for4hours, the dried sol exhibits obvious anatase characteristic peak in XRD spectrum, the size of particle is10.8nano, when SiO2sol or SiO2is added the crystal grain of the anatase TiO2will decrease; XPS analysis indicates that when SiO2is added, there are some defect in TiO2and some titanium atoms exist in form of+3.And O element exists in three forms, one is O-H, one is O-Ti, another is O-Si; The show that the a small amount of silicon element into the crystal lattice of TiO2after the SiO2sol/TiO2sol microwaved. The rusults of UV-vis explain that the microwave causes wavelength of TiO2sol blue shift and the wavelengh is361nm. The microwaved sol has strong photocatalytic ability toward methyl orange under UV illumination. Decoloring efficiency could be up to94.7%with only15min of UV source lighting.2. Fluorocarbon coating are modified by anatase TiO2sol or microwaved TiO2/SiO2and we discuss the introduction of the anatase TiO2sol or the TiO2/SiO2has the effect on hardness, adhesion, photocatalytic, etc. The introduction of TiO2can improve the hardness and adhesion of the coating,the introduction of SiO2can reduce the adhesion but improve the hardness; whatever, the fluorocarbon coating modified by anatase TiO2sol or microwaved TiO2/SiO2has the photocatalytic capability and super hydrophilic,the stain resistance of modified fluorocarbon coating also improves and there are almost nothing influence on acidproof alkalescence and weather resistance; but the fluorocarbon coating are modified by microwaved TiO2/SiO2much better. The best introduction TiO2content is1.5wt%and SiO2content is0.3wt%.3. The uniform particle size of nano SiO2particles was synthesized via Stober method, then the SiO2particles was modified by KH550, the SiO2particles and the modified coating are characterized by FTIR、TG-DTA、XRD、TEM and interfacial tension measuring instrument, the result show that, the size of SiO2particlessynthesized by Stober method was10.8mn; the KH550had been grafted successfully on the surface of SiO2and grafting is5.19%; the modified SiO2particles was dispersed in the fluorocarbon resin. With the introduction of SiO2increasing, the contact angle with water also became larger,when the introduction of SiO2particles reached5wt%the coating contact angle with water was136°and had obvious self-cleaning function...