Pattern formation by dewetting and evaporating sedimenting suspensions
Pattern formation by dewetting and evaporating sedimenting suspensions
复制标题
DOI：
10.1039/c2sm07201g
复制
发表时间：
2012-01-01
期刊：
影响因子：
3.4
通讯作者：
Bonn, Daniel
中科院分区：
文献类型：
--
作者：
Habibi, Mehdi;Moller, Peder;Bonn, Daniel
图案形成从干燥液滴含有沉淀颗粒和去湿薄膜的这种悬浮液进行了研究。去湿导致在接触线附近形成指状图案，其留下分支的存款。我们发现，显着低的速度去湿是由于高颗粒浓度的接触线区域，导致强烈增强的粘度。对于由干燥液滴（含有颗粒）形成图案，蒸发也会导致去湿。在这两种情况下，我们发现图案的大小和去湿速度之间存在类似的关系。该关系的系数给出了接触线处的有效粘度。我们提出了一个简单的模型，说明了这一点，并表明，在这两个问题中，颗粒的大小是相关的长度尺度。
Pattern formation from drying droplets containing sedimenting particles and dewetting of thin films of such suspensions was studied. The dewetting causes the formation of finger-like patterns near the contact line which leave behind a deposit of branches. We find that the strikingly low speed of dewetting is due to the high particle concentration in the contact line region, leading to a strongly enhanced viscosity. For pattern formation from drying droplets (containing particles), evaporation also causes dewetting. In both cases, we find a similar relationship between the size of the patterns and the dewetting speed. The coefficient of this relationship gives us the effective viscosity at the contact line. We present a simple model that accounts for this, and that shows that the size of the particles is the relevant length scale in both problems.