Cohen-Addad Sylvie, Höhler Reinhard, Khidas Yacine
L.P.M.D.I./U.M.R. 8108, C.N.R.S., Université de Marne-la-Vallée, 5 Boulevard Descartes, 77454 Marne-la-Vallée, France.
Phys Rev Lett. 2004 Jul 9;93(2):028302. doi: 10.1103/PhysRevLett.93.028302. Epub 2004 Jul 8.
We have studied the slow linear viscoelastic response of wet aqueous foams by macroscopic creep compliance measurements, combined to a diffusing-wave spectroscopy investigation of the local dynamics. The data strongly suggest that this rheological response arises from two distinct relaxation mechanisms: The first is due to the coarsening induced bubble rearrangements and governs the steady-state creep; the second results from the interplay between surface tension and surface viscosity of the gas-liquid interfaces and gives rise to a transient relaxation.
