2018 Impact factor 1.686
Soft Matter and Biological Physics

Eur. Phys. J. E 1, 249-262

Stability of droplets and channels on homogeneous and structured surfaces

P. Lenz - R. Lipowsky

Max-Planck-Institut für Kolloid- und Grenzflächenforschung, 14424 Potsdam, Germany
lenz@cmtql.harvard.edu, lipowsky@mpikg-golm.mpg.de

Received 4 August 1999

Abstract
Wetting of structured or imprinted surfaces which leads to a variety of different morphologies such as droplets, channels or thin films is studied theoretically using the general framework of surface or interface thermodynamics. The first variation of the interfacial free energy leads to the well-known Laplace equation and a generalized Young equation which involves spatially dependent interfacial tensions. Furthermore, we perform the second variation of the free energy for arbitrary surface patterns and arbitrary shape of the wetting morphology in order to derive a new and general stability criterion. The latter criterion is then applied to cylindrical segments or channels on homogeneous and structured surfaces.

PACS
68.45.Gd Wetting - 68.10.Cr Surface energy (surface tension, interface tension, angle of contact, etc.) - 47.20.Dr Surface-tension-driven instability

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