Contact-line friction of liquid drops on self-assembled monolayers: chain-length effects.

Langmuir

Centre de Recherches en Modélisation Moléculaire, Université de Mons-Hainaut/Materia Nova, Parc Initialis, Av. Copernic, 1, B-7000 Mons, Belgium.

Published: April 2007

The static and dynamic wetting properties of self-assembled alkanethiol monolayers of increasing chain length were studied. The molecular-kinetic theory of wetting was used to interpret the dynamic contact angle data and evaluate the contact-line friction on the microscopic scale. Although the surfaces had a similar static wettability, the coefficient of contact-line friction zeta0 increased linearly with alkyl chain length. This result supports the hypothesis of energy dissipation due to a local deformation of the nanometer-thick layer at the contact line.

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http://dx.doi.org/10.1021/la062884rDOI Listing

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