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arXiv · 0907.2113

Liquid Front Profiles Affected by Entanglement-induced Slippage

O. Baeumchen·R. Fetzer·K. Jacobs
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Abstract

Hydrodynamic slippage plays a crucial role in the flow dynamics of thin polymer films, as recently shown by the analysis of the profiles of liquid fronts. For long-chained polymer films it was reported that a deviation from a symmetric profile is a result of viscoelastic effects. In this Letter, however, evidence is given that merely a slip boundary condition at the solid/liquid interface can lead to an asymmetric profile. Dewetting experiments of entangled polymer melts on diverse substrates allow a direct comparison of rim morphologies. Variation of molecular weight Mw clearly reveals that slippage increases dramatically above a certain Mw and governs the shape of the rim. The results are in accordance with the theoretical description by de Gennes.

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O. Baeumchen, R. Fetzer, K. Jacobs. 2009-07-13. Liquid Front Profiles Affected by Entanglement-induced Slippage. https://arxiv.org/abs/0907.2113

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