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Published on: October 25, 2017
Microstructure of Sheared Entangled Solutions of Semiflexible Polymers
Marc Lämmel1, Evelin Jaschinski2, Rudolf Merkel3
1Institut für theoretische Physik, Universität Leipzig, Postfach 100920, 04009 Leipzig, Germany. marc.laemmel@itp.uni-leipzig.de.
Abstract:
We study the influence of finite shear deformations on the microstructure and rheology of solutions of entangled semiflexible polymers theoretically and by numerical simulations and experiments with filamentous actin. Based on the tube model of semiflexible polymers, we predict that large finite shear deformations strongly affect the average tube width and curvature, thereby exciting considerable restoring stresses. In contrast, the associated shear alignment is moderate, with little impact on the average tube parameters, and thus expected to be long-lived and detectable after cessation of shear. Similarly, topologically preserved hairpin configurations are predicted to leave a long-lived fingerprint in the shape of the distributions of tube widths and curvatures. Our numerical and experimental data support the theory.
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