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arXiv · cond-mat/0512100

Slow viscoelastic relaxation and aging in aqueous foam

S. Vincent-Bonnieu·R. Höhler·S. Cohen-Addad
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Abstract

Like emulsions, pastes and many other forms of soft condensed matter, aqueous foams present slow mechanical relaxations when subjected to a stress too small to induce any plastic flow. To identify the physical origin of this viscoelastic behaviour, we have simulated how dry disordered coarsening 2D foams respond to a small applied stress. We show that the mechanism of long time relaxation is driven by coarsening induced rearrangements of small bubble clusters. These findings are in full agreement with a scaling law previously derived from experimental creep data for 3D foams. Moreover, we find that the temporal statistics of coarsening induced bubble rearrangements are described by a Poisson process.

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S. Vincent-Bonnieu, R. Höhler, S. Cohen-Addad. 2005-12-05. Slow viscoelastic relaxation and aging in aqueous foam. https://doi.org/10.1209/epl%2Fi2005-10546-7

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