"Tuliplike" scattering patterns in wormlike micelles under shear flow.

Abstract

Using small angle light scattering we report on the formation of a string phase in a semidilute solution of wormlike micelles (0.03M CTAB/0.24M NaSal) under simple shear flow. The string phase appears as a bright narrow streak in the scattering pattern normal to the flow direction. We also study the relaxation behavior after cessation of flow, and using the Brochard--de Gennes model we are able to estimate the stress relaxation time ${\ensuremath{\tau}}_{s}$ and diffusion coefficient ${D}_{c}$ of the dominant relaxation mode.