Rheology of wormlike micellar gels formed by long-chained zwitterionic surfactants.

Long-chained surfactant solutions have found widespread use in the oil and gas industry due to a host of attractive properties. In this paper, we characterize one such commercially used viscoelastic surfactant that forms a wormlike micellar gel at room temperature and a viscoelastic solution at higher temperatures. We probe both states by conducting linear and nonlinear rheological tests and analyze their behavior under the framework of micellar rheology. Our study outlines departure from behavior exhibited by more conventional micellar systems and uncovers interesting dynamics like shear-induced fracture and possible shear-banding in these materials. In doing so, we provide a detailed understanding of a novel class of wormlike micellar solutions. [ABSTRACT FROM AUTHOR]