燃烧合成疏水BN粉体和超疏水涂层的制备及其性能表征

具有分级结构的BN纳米薄膜展现出优异的超疏水性, 但由于该薄膜的制备过程复杂、成本昂贵, 不适宜大规模的生产和应用。与之相比, 基于疏水BN粉体的超疏水涂层的应用会更为便捷。本研究采用镁热还原氮化燃烧合成法结合酸洗工艺制备了疏水的单相BN粉体, 水接触角为(144.6±2.4)°, 疏水性可以归因于BN粉体颗粒具有的微纳分级结构。在此基础上, 以这种燃烧合成的疏水BN粉体为填料制备的BN/氟硅树脂复合涂层进一步表现出超疏水性, 其中质量分数30% BN/FSi树脂涂层的水接触角为(151.2±0.7)°, 滚动角约为8°。该涂层与文献报道的通过CVD方法制备的BN纳米薄膜的性能相当, 但工艺更加简单。这是一种利用陶瓷粉体的疏水性来制备超疏水有机无机复合涂层的简便易行的新方法, 有望获得广泛的工程应用。

Hydrophobic BN Powders by Combustion Synthesis and Its Super-hydrophobic Coatings: Preparation and Property

BN nanofilms with hierarchical structure exhibite super-hydrophobicity, but they are not suitable for the large-scale production and application due to their complicated preparation process and expensive cost. Compared with common BN nanofilms, the application of super-hydrophobic coatings based on hydrophobic BN powders are more convenient. Herein, the hydrophobic single-phase BN powders were prepared by combustion synthesis method through magnesiothermic reduction reaction and acid washing, showing the water contact angle at (144.6±2.4)°. Their hydrophobic character lies in the micro-nano hierarchical structure of BN particles. The super-hydrophobic BN/fluorosilicone resin coatings were prepared using the combustion-synthesized hydrophobic BN powders as fillers. The water contact angle and sliding angle for 30% BN/fluorosilicone resin coatings (in mass) are (151.2±0.7)° and 8°, respectively, which are comparable to that of BN nanofilms fabricated by CVD method reported in the literature. This method is a convenient way to prepare super-hydrophobic organic-inorganic composite coatings by utilizing the hydrophobicity of ceramic powders. Therefore, hydrophobic BN powders and super-hydrophobic BN/fluorosilicone resin coatings are expected to have wide application.