Ribbon phase in a phase-separated lyotropic lamellar-sponge mixture under shear flow - art. no. 011505

We report the effect of shear flow on a phase-separated system composed of lyotropic lamellar (L-alpha) and sponge (L-3) phases in a mixture of brine, surfactant, and cosurfactant. Optical microscopy, small-angle light, and x -ray scattering measurements are consistent with the existence of a steady state made of multilamellar ribbonlike structures aligned in the flow direc tion. At high shear rates. these ribbonlike structures become unstable and break up into monodisperse droplets resulting in a shear-thickening transit ion.