Spinodal dewetting of thin liquid films at soft interfaces

A. Martin; O. Rossier; A. Buguin; P. Auroy; F. Brochard-Wyart

doi:doi:10.1007/s101890070004

2022 Impact factor 1.8

Soft Matter and Biological Physics

Eur. Phys. J. E 3, 337-341

Spinodal dewetting of thin liquid films at soft interfaces

A. Martin - O. Rossier - A. Buguin - P. Auroy - F. Brochard-Wyart

UMR 168, Institut Curie, Section de Recherche, PCC, 26 rue d'Ulm - 75248 Paris, Cedex 05, France
brochard@curie.fr

Received 11 February 2000 and Received in final form 22 May 2000

Abstract
We study theoretically the behavior of nanoscopic liquid films L (thickness e) intercalated between a solid S and a rubber R (elastic modulus $\mu$ ). Thickness modulations involve a healing length $\zeta_R$ , which results from a competition between elastic and disjoining pressure. With van der Waals interactions, $\zeta_R=e^4/(a^2h_0)$ , where a is a molecular size and h₀ the rubber capillary length ( $h_0=\gamma_LR/\mu$ , $\gamma_LR=L/R$ interfacial tension). If the Hamaker constant of the intercalated liquid is negative, the film dewets by amplification of peristaltic fluctuations ("spinodal dewetting''). The typical size of the S/R contacts is predicted to scale like $\zeta_R$ for films of thicknesses $e>\sqrt{h_0a}$ . The rise time $\tau$ of the fastest mode, predicted to scale like $\tau\approx e^9$ , should be very sensitive to the film thickness.