Department of Mechanical and Aerospace Engineering, UCLA, Los Angeles, CA 90025, USA.
Department of Mechanical and Industrial Engineering, UMass Amherst, Amherst, MA 01003, USA.
J Colloid Interface Sci. 2018 Mar 1;513:658-665. doi: 10.1016/j.jcis.2017.11.075. Epub 2017 Dec 2.
Rough hydrophobic surfaces have many applications in industry and technology. An experimental study was done on the spreading dynamics of different concentrations of polyethylene glycol (PEG) solutions on rough Teflon plates with different roughness. The experiments were conducted using Wilhelmy plate method. The advancing dynamic contact angle was found to be weakly dependent of capillary number. However, the receding dynamic contact angle decreases with increasing capillary number. The degree of roughness on rough Teflon surface has an important role on dynamic contact angle. The dynamics of receding motion was found to follow the molecular-kinetic theory. A power law relation between the receding dynamic contact angle and the capillary number was also obtained.
粗糙的疏水面在工业和技术中有许多应用。本研究通过使用 Wilhelmy 板法对不同浓度的聚乙二醇（PEG）溶液在具有不同粗糙度的粗糙聚四氟乙烯（Teflon）板上的铺展动力学进行了实验研究。结果表明，前进动态接触角与毛细数的关系较弱。然而，后退动态接触角随毛细数的增加而减小。粗糙 Teflon 表面的粗糙度对动态接触角有重要作用。后退运动的动力学符合分子动力学理论。还得到了后退动态接触角与毛细数之间的幂律关系。
