Capillary Rise and Flow of Complex Liquids in Nanopores

我们建议研究的整体，多孔硅玻璃和多孔硅（平均孔径d = 10 nm）的复杂液体的流动作为一个功能的大小和形状的积木的液体和所施加的剪切速率。特别地，我们想比较在膜流动装置中进行的流速测量与自发吸胀的测量，即由毛细力驱动的孔隙中的毛细上升。而流动装置的测量将允许我们确定的nanobolined液体的粘度，毛细管上升的填充过程至关重要地不仅取决于粘性阻力，而且还取决于作用在纳米孔中的毛细管压力。为了改变液体的复杂性，我们建议测量由链状（正烷烃）、棒状和盘状（液晶）分子构成的液体-所有这些分子的分子大小都与纳米孔的直径相当。实验研究将揭示这个问题，以延长连续的，宏观的流体行为是有效的到纳米尺度。

We propose to study the flow of complex liquids in monolithic, porous silica glasses and porous silicon (mean pore diameter d = 10nm) as a function of the size and shape of the building blocks of the liquids and the applied shear rates. In particular, we would like to compare flow rate measurements taken in a membrane flow apparatus with measurements on the spontaneous imbibition, that is the capillary rise in the pores driven by capillary forces. Whereas the flow apparatus measurements will allow us to determine the viscosities of the nanoconfined liquids, the filling process of the capillary rise crucially depends not only on the viscous drag but also on the capillary pressure acting in the nanopores. In order to vary the complexity of the liquids we suggest to measure liquids built out of chain-like (n-alkanes), rod-like and disc-like (liquid crystals) molecules - all of them with molecular sizes on the order of the diameter of the nanopores. The experimental study will shed light on the question to what extend continuum-like, macroscopic fluid behavior is valid down to nano-scopic lenght scales.