修饰不同微结构对疏水性表面浸润性的影响

目的研究修饰微结构对疏水性材料表面浸润性的影响并指导制备超疏水表面。方法基于有限元软件建立了水滴在修饰不同微结构的疏水性表面的润湿模型,通过水滴表观接触角衡量分析了疏水材料表面修饰单一粗糙结构和复合粗糙结构对疏水性提升的效果,利用硅树脂掺杂微粒制备了不同粗糙度的疏水性涂层,涂层固化后测试其实际接触角大小,并与仿真结果对比。结果仿真结果显示,对水滴接触角为100°的表面修饰单一粗糙结构后,由于微结构形成的凹槽滞留空气,阻碍了水滴在表面铺展,使得水滴在表面的接触角增大至133°。在原微结构基础上修饰更小一级的微结构后,水滴在表面的接触角达168°,材料表面达到超疏水效果。实验中,随涂层表面粗糙度的提升,水滴在表面的接触角逐渐增大,掺混两种微粒的疏水涂层固化后,表面形成复合微观结构,水滴接触角达162°,与仿真结果拟合较好。结论在疏水性表面修饰微结构可显著提升其表面疏水性,修饰复合结构后可达到超疏水效果,此方法可用于实际工程制备超疏水表面。

Effects of Modification of Different Microstructures on Wettability of Hydrophobic Surface

The work aims to study the effects of microstructure modification on hydrophobic material surface, and provide guidance for preparation of superhydrophobic surface. Based on finite element software, a wettability model in which water droplets modify different microstructures of hydrophobic surface was established. The effects of single rough structure and composite rough structure modified with hydrophobic materials on improving hydrophobicity were measured and analyzed using apparent contact angle of water droplets. Hydrophobic coatings of different roughness were prepared using silicon resin-doped particles and then cured. Actual contact angle was tested and compared with simulation results. After single rough structure was modified for the surface with water droplet contact angle of 100°, contact angle of water droplet on the surface increased to 133° as groove formed by microstructure obstructed air and prevented water droplet from spreading on the surface. Then the contact angle reached 168° after smaller microstructure was modified on the original microstructure, which was similar to superhydrophobic surface. The contact angle of water droplet increased as surface roughness increased in the actual experiment, which reached 162° as composite microstructure formed on the surface after curing of the hydrophobic coating containing two kinds of particles. The experimental data fitted well with the simulation result. Modifying microstructure on hydrophobic surface can significantly improve surface hydrophobicity., The surface will be superhydrophobic after composite structure is modified, which can be used for preparing superhydrophobic surface in actual engineering.