Aging and yielding in a sheared AOT/iso-octane/water lyotropic lamellar phase.
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.
Auffret
Y
Y
Laboratoire de Rhéologie UMR 5520, Domaine Universitaire, BP53, 38041, Grenoble Cedex 9, France. yann.auffret@ujf-grenoble.fr
Roux
D C D
DC
El Kissi
N
N
Caton
F
F
Pignot-Paintrand
I
I
Dunstan
D E
DE
Rochas
C
C
D004143:Dioctyl Sulfosuccinic Acid / Q000737:chemistry*; D009795:Octanes / Q000737:chemistry*; D044367:Phase Transition; D015203:Reproducibility of Results; D013997:Time Factors; D014867:Water / Q000737:chemistry*
D009795:Octanes; D014867:Water; D004143:Dioctyl Sulfosuccinic Acid; C026728:octane