| Abstract
| - Slippage of Newtonian liquids in the presence of a solid substrate is a newly found phenomenon, the origin of whichis still under debate. In this article, we present a new analysis method to extract the slip length. Enhancing the slipof liquids is an important issue for microfluidic devices that demand for high throughput at low pumping power. Westudy the velocity of short-chained liquid polystyrene (PS) films dewetting from nonwettable solid substrates. Weshow how the dynamics of dewetting is influenced by slippage, and we compare the results of two types of substratesthat give rise to different slip lengths. As substrates, Si wafers that have been coated with octadecyltrichlorosilane(OTS) or dodecyltrichlorosilane (DTS) were used. Our results demonstrate that the dewetting velocity for PS filmson DTS is significantly larger than on OTS and that this difference originates from the different slip lengths of theliquid on top of the two surfaces. For PS films of thickness between 130 and 230 nm, we find slip lengths between400 nm and 6 μm, depending on substrate and temperature.
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