title: Structural signature of a brittle-to-ductile transition in self-assembled networks.
abstract: We study the nonlinear rheology of a novel class of transient networks, made of surfactant micelles of tunable morphology reversibly linked by block copolymers. We couple rheology and time-resolved structural measurements, using synchrotron radiation, to characterize the highly nonlinear viscoelastic regime. We propose the fluctuations of the degree of alignment of the micelles under shear as a probe to identify a fracture process. We show a clear signature of a brittle-to-ductile transition in transient gels, as the morphology of the micelles varies, and provide a parallel between the fracture of solids and the fracture under shear of viscoelastic fluids.
authors: Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095, Montpellier, France. laurence.ramos@univ-montp2.fr
authors: Laurence
authors: L
authors: Ramos
authors: Arnaud
authors: A
authors: Laperrousaz
authors: Philippe
authors: P
authors: Dieudonné
authors: Christian
authors: C
authors: Ligoure