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arXiv · 1203.0951

Structural Signature of a Brittle-to-Ductile Transition in Self-Assembled Networks

Laurence Ramos·Arnaud Laperrousaz·Philippe Dieudonne·Christian Ligoure
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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.

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Laurence Ramos, Arnaud Laperrousaz, Philippe Dieudonne, Christian Ligoure. 2012-03-05. Structural Signature of a Brittle-to-Ductile Transition in Self-Assembled Networks. https://doi.org/10.1103/physrevlett.107.148302

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