3D打印制备各向异性超疏水功能表面的定向输送性能

Directional Transport Properties of Anisotropic Superhydrophobic Functional Surfaces Prepared by 3D Printing

目的在光敏树脂基底上制备各向异性超疏水功能表面,实现液滴的定向输送。方法采用光固化逐层成形3D打印法,在样品基底上制备具有不同形状和结构尺寸的超疏水结构阵列。通过扫描电子显微镜(SEM)、EDS能谱分析,对样品的表面形貌与化学成分变化进行表征。采用接触角检测系统、高速摄像机,通过液滴弹跳、各向异性润湿性与定向输送实验,分析与评价不同阵列表面的超疏水性能、各向异性润湿程度以及定向输送行为。结果液滴弹跳实验结果表明,液滴可在正方体及交错长方体阵列表面形成饼状弹跳,且后者超疏水性能最佳。各向异性润湿性实验结果表明,在圆柱体阵列中,各向异性润湿性程度随相邻圆柱体高度差Δh的增大而趋于显著,且Δh=1 mm时,各向异性润湿性最为显著;在长方体阵列中,长方体宽度w1及相邻长方体间距sp1对各向异性润湿性程度均有一定影响,w1=0.3 mm、sp1=1 mm时,各向异性润湿性最为显著。定向输送实验结果表明,Δh=1 mm的圆柱体阵列及w2=0.7 mm、sp2=0.7 mm的长方体阵列的定向输送性能最佳,液滴可按照设计的路线精准流动。结论3D打印所制备的光敏树脂基功能表面的超疏水性能、各向异性润湿程度以及定向输送行为由其表面形貌和结构尺寸所决定,所制备的样品可实现液滴的精准定向输送。

The work aims to prepare the anisotropic superhydrophobic functional surface on the photosensitive resin substrate and realize the directional transport of the droplet.Superhydrophobic arrays with different shapes and sizes were prepared on the substrate by stereo lithography appearance(SLA)method.The surface morphology and chemical composition of the sample were characterized by scanning electron microscopy(SEM)and EDS spectroscopy.The contact angle detection system and high-speed camera were used to analyze and evaluate the superhydrophobic properties,anisotropic wetting degree and directional transport behavior of different array surfaces through droplet bounce,anisotropic wettability and directional transport experiments.The results of droplet bounce experiments showed that the droplets could achieve a cake-like bounce on the cube and interlaced cuboid array,and the superhydrophobic performance of the latter was best.The experimental results of anisotropic wettability showed that the degree of anisotropic wettability tended to be significant with the increase of height differenceΔh of adjacent cylinders in the cylindrical array,and it was the most onΔh=1 mm.The cuboid width w1 and adjacent cuboid spacing sp1 of rectangular parallelepiped array also had an effect on anisotropic wettability,and the anisotropic wettability was the most on w1=0.3 mm and sp1=1 mm.The results of directional transport experiments showed that the directional transport performance of the cylindrical array withΔh=1mm and rectangular parallelepiped array with w2=0.7 mm and sp2=0.7 mm were the best,and the droplets could slide accurately along designed routes.The superhydrophobic property,anisotropic wetting degree and directional transport behavior of photosensitive resin-based functional surface prepared by 3D printing are determined by the surface morphology and structure size,and the prepared sample can realize the directional transport of the droplets precisely.