高耐磨超疏水高分子复合涂层设计、制备和性能研究

发布时间：2018-12-26 11:26

【摘要】：疏水表面是指与水的接触角大于90°的表面,超疏水表面则是指与水的接触角大于150°、滚动角小于10°的表面。超疏水表面在自清洁、防水、防冰等方面具有广阔的应用前景。提高耐磨性是超疏水表面工程的研究热点和难点。针对大型风电叶片、飞机机翼等大型复合材料结构抗冰实际需求,研究耐磨性能好的超疏水涂层具有很重要的应用价值。本文采用耐磨性好、具有本征疏水特性的二氧化铈微纳粒子和氟硅丙改性聚氨酯树脂,设计新型超疏水涂层配方,采用工艺简单、条件易控的流延法和喷涂法在玻纤/环氧树脂复合材料基板上制备超疏水涂层。配方设计主要考虑不同粒径纳米粒子及其组合与树脂和稀释剂的配比优化问题。重点研究了10μm、1μm和100nm粒径的CeO_2粒子的不同含量以及微米和纳米粒子组合对超疏水涂层疏水性和耐磨性的影响,分析了超疏水涂层的微观结构特点,优化了超疏水涂层配方。首先,将不同粒径的CeO_2粒子分别与氟硅丙改性聚氨酯树脂和稀释剂按照不同的配比均匀混合,制成高分子复合涂料。采用流延法和喷涂法在基板上制备超疏水涂层,测试水珠接触角,找出最优配比。研究表明,喷涂法制备的复合涂层的接触角为148.88°,流延法制备的复合涂层的接触角为145.41°,均显示出良好的疏水性能。其次,在最优配比的基础上研究微米纳米组合粒径对超疏水涂层性能的影响。进一步优化涂层的超疏水性能之后,采用落沙法测试复合涂层的耐磨性。流延法制备的10μm粒子复合涂层的耐磨性最好,优于使用喷涂法工艺和其他粒径制备的复合涂层。最好的涂层配方为树脂与粒子和稀释剂之比为0.5:0.5:1.5。最后,采用扫描电镜对不同配方、不同工艺制备的复合涂层表面微观形貌进行观察与分析。所制备的复合涂层样品表面均能构筑微纳二元结构,具有较好的疏水性能。复合涂层在经过落沙冲击磨损后,包覆在粒子外面的表层树脂受到一定程度的破坏,粒子由树脂团里裸露出来,反而更好的构筑微纳二元结构,使得疏水性能进一步提升,涂层持续磨损后的接触角一直保持在150°以上。研究进一步发现,只要涂层未被磨穿则一直保持良好的超疏水效果,这个发现有利于通过涂层厚度来调控超疏水涂层的耐磨能力。
[Abstract]:The hydrophobic surface refers to the surface whose contact angle with water is greater than 90 掳, while the superhydrophobic surface refers to the surface whose contact angle with water is greater than 150 掳and whose rolling angle is less than 10 掳. Superhydrophobic surface has a broad application prospect in self-cleaning, waterproof, ice-proof and so on. Improving wear resistance is a hot and difficult point in superhydrophobic surface engineering. In order to meet the practical requirements of ice resistance of large composite structures such as large wind power blades and aircraft wings, it is of great value to study super hydrophobic coatings with good wear resistance. In this paper, a new type of super hydrophobic coating formula was designed by using cerium oxide micro-nano particles and fluorosilicone-acrylic modified polyurethane resin with good wear resistance and intrinsic hydrophobic properties. Superhydrophobic coatings were prepared on glass fiber / epoxy composite substrates by flow casting and spraying. The formulation design mainly considers the optimization of the ratio of different particle size and its combination with resin and diluent. The effects of different contents of 10 渭 m 1 渭 m and 100nm particle size on the hydrophobicity and wear resistance of superhydrophobic coatings were studied, and the microstructure of superhydrophobic coatings was analyzed. The formulation of superhydrophobic coating was optimized. Firstly, polymer composite coatings were prepared by mixing CeO_2 particles of different particle sizes with fluorosilicone-acrylic modified polyurethane resin and diluent according to different ratios. The superhydrophobic coating was prepared on the substrate by the method of casting and spraying, and the contact angle of the water droplets was measured to find out the optimum ratio. The results show that the contact angle of the composite coating prepared by spraying method is 148.88 掳, and the contact angle of the composite coating prepared by casting method is 145.41 掳, which shows good hydrophobic properties. Secondly, the effect of micron and nano particle size on the properties of superhydrophobic coatings was studied on the basis of the optimal ratio. After the superhydrophobicity of the coating was optimized, the wear resistance of the composite coating was tested by sand drop method. The wear resistance of 10 渭 m particle composite coating prepared by casting method is the best, which is superior to that of the composite coating prepared by spraying process and other particle sizes. The best coating formula is the ratio of resin to particle and diluent to 0.5: 0.5: 1.5. Finally, SEM was used to observe and analyze the surface morphology of the composite coatings prepared with different formulations and different processes. The surface of the composite coating has good hydrophobic properties, and the micro-nano binary structure can be constructed on the surface of the composite coating. After the impact wear of the composite coating, the resin coated on the surface of the particles is destroyed to a certain extent, and the particles are exposed from the resin cluster. Instead, the micro-nano binary structure is better constructed, so that the hydrophobicity can be further enhanced. The contact angle of the coating remained above 150 掳after continuous wear. It is further found that as long as the coating is not worn through, the superhydrophobic effect will be maintained, which is helpful to regulate the wear resistance of the superhydrophobic coating through the thickness of the coating.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB306

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