Eur. Phys. J. E (2009) 29: 51-60
https://doi.org/10.1140/epje/i2009-10450-6

Regular Article

Aging and yielding in a sheared AOT/iso-octane/water lyotropic lamellar phase

¹ Laboratoire de Rhéologie UMR 5520, Domaine Universitaire, BP53, 38041, Grenoble Cedex 9, France
² CERMAV UPR 5301, Domaine Universitaire, BP53, 38041, Grenoble Cedex 9, France
³ Department of Chemical and Biomolecular Engineering, The University of Melbourne, 3010, Victoria, Australia
⁴ Laboratoire de Spectrométrie Physique UMR 5588, 140 Av. de la Physique, BP87, 38042, st Martin d’Hères, France

^* e-mail: yann.auffret@ujf-grenoble.fr
^** e-mail: denis.roux@ujf-grenoble.fr

Received: 6 June 2008
Revised: 23 January 2009
Accepted: 6 March 2009
Published online: 3 May 2009

Abstract

We define a creep-flow-based measurement procedure to allow reliable and reproducible results on aging and yielding materials to be obtained. Investigation of the effects of different parameter such as the pre-shear time, the recovery time and the applied stress magnitude on the viscoelastic properties of a lyotropic liquid crystal phase is reported. Cryo-TEM observations indicate the formation of multiconnected bilayers at rest. Shearing the investigated material shows a propensity to acquire all the macroscopic properties of “soft jammed systems”. These properties are then interpreted in terms of shear-induced structural rearrangement on the basis of cryofracture observation obtained at different times after the preshear imposed.