Partial wetting of chemically patterned surfaces: The effect of drop size
Partial wetting of chemically patterned surfaces: The effect of drop size
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DOI：
10.1016/s0021-9797(03)00285-6
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发表时间：
2003-07-01
影响因子：
9.9
通讯作者：
Marmur, A
中科院分区：
文献类型：
--
作者：
Brandon, S;Haimovich, N;Marmur, A
部分润湿化学异质衬底进行了模拟。被认为是三维固着滴在平衡与光滑的表面支持有序的化学图案。作为改变液滴体积的结果，观察到显著特征。平衡液滴的数量被发现要么保持不变，或增加与增长的液滴体积。较大的液滴的形状似乎接近球形帽的形状，并且它们的三相接触线在较大的尺度上似乎比较小的液滴的形状更圆。此外，随着体积的增加，在相同体积的所有平衡形状的液滴中自由能最低的液滴的平均接触角似乎接近Cassie预测的角度。最后，与二维液滴获得的结果相反，在该系统中观察到的接触角滞后显示出一定程度的体积依赖性的前进和后退角。与这里考虑的两种不同的化学图案相关的润湿行为的定性差异，以及与二维和三维液滴获得的结果之间的差异，可能是由于不同的图案和系统的维数对液滴施加的约束水平的变化。(C)2003 Elsevier Science（美国）。All rights reserved.
Partial wetting of chemically heterogeneous substrates is simulated. Three-dimensional sessile drops in equilibrium with smooth surfaces supporting ordered chemical patterns are considered. Significant features are observed as a result of changing the drop volume. The number of equilibrated drops is found either to remain constant or to increase with growing drop volume. The shape of larger drops appears to approach that of a spherical cap and their three-phase contact line seems, on a larger scale, more circular in shape than that of smaller drops. In addition, as the volume is increased, the average contact angle of drops whose free energy is lowest among all equilibrium-shaped drops of the same volume appears to approach the angle predicted by Cassie. Finally, contrary to results obtained with two-dimensional drops, contact angle hysteresis observed in this system is shown to exhibit a degree of volume dependence in the advancing and receding angles. Qualitative differences in the wetting behavior associated with the two different chemical patterns considered here, as well as differences between results obtained with two-dimensional and three-dimensional drops, can possibly be attributed to variations in the level of constraint imposed on the drop by the different patterns and by the dimensionality of the system. (C) 2003 Elsevier Science (USA). All rights reserved.