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arXiv · 1511.00837

Self-organization in suspensions of end-functionalized semiflexible polymers under shear flow

Jin Suk Myung·Roland G. Winkler·Gerhard Gompper
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Abstract

The nonequilibrium dynamical behavior and structure formation of end-functionalized semiflexible polymer suspensions under flow are investigated by mesoscale hydrodynamic simulations. The hybrid simulation approach combines the multiparticle collision dynamics method for the fluid, which accounts for hydrodynamic interactions, with molecular dynamics simulations for the semiflexible polymers. In equilibrium, various kinds of scaffold-like network structures are observed, depending on polymer flexibility and end-attraction strength. We investigate the flow behavior of the polymer networks under shear and analyze their nonequilibrium structural and rheological properties. The scaffold structure breaks up and densified aggregates are formed at low shear rates, while the structural integrity is completely lost at high shear rates. We provide a detailed analysis of the shear-rate-dependent flow-induced structures. The studies provide a deeper understanding of the formation and deformation of network structures in complex materials.

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Jin Suk Myung, Roland G. Winkler, Gerhard Gompper. 2015-11-03. Self-organization in suspensions of end-functionalized semiflexible polymers under shear flow. https://doi.org/10.1063/1.4933368

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