Capillarity of soft amorphous solids: A microscopic model for surface stress

Joost H. Weijs, Jacco H. Snoeijer, Bruno Andreotti

Research output: Contribution to journalArticleAcademicpeer-review

17 Citations (Scopus)
29 Downloads (Pure)

Abstract

The elastic deformation of a soft solid induced by capillary forces crucially relies on the excess stress inside the solid-liquid interface. While for a liquid-liquid interface this "surface stress" is strictly identical to the "surface free energy," the thermodynamic Shuttleworth equation implies that this is no longer the case when one of the phases is elastic. Here we develop a microscopic model that incorporates enthalpic interactions and entropic elasticity, based on which we explicitly compute as the surface stress and surface free energy. It is found that the compressibility of the interfacial region, through the Poisson ratio near the interface, determines the difference between surface stress and surface energy. We highlight the consequence of this finding by comparing with recent experiments and simulations on partially wetted soft substrates.

Original languageEnglish
Article number042408
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Volume89
Issue number4
DOIs
Publication statusPublished - 28 Apr 2014

Fingerprint Dive into the research topics of 'Capillarity of soft amorphous solids: A microscopic model for surface stress'. Together they form a unique fingerprint.

  • Cite this