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arXiv · 0809.3041

Dynamics of polymers in elongational flow investigated by inelastic neutron scattering

Maikel C. Rheinstadter·Rainer Sattler·Wolfgang Haeussler·Christian Wagner
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Abstract

The nanoscale fluctuation dynamics of semi dilute high molecular weight polymer solutions of Polyethylenoxide (PEO) in D2O under non-equilibrium flow conditions were studied by the neutron spin-echo technique. The sample cell was in contraction flow geometry and provided a pressure driven flow with a high elongational component that stretched the polymers most efficiently. The experiments suggest that the mobility on the scale of a few monomers, comparable to the Kuhn segment length, becomes highly anisotropic and is enhanced perpendicular to the flow direction. Diffraction data show a weak structural correlation along the chains on a length scale of about 17 Angstroems, which might be related to the Kuhn length in this system.

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Maikel C. Rheinstadter, Rainer Sattler, Wolfgang Haeussler, Christian Wagner. 2008-09-18. Dynamics of polymers in elongational flow investigated by inelastic neutron scattering. https://doi.org/10.1016/j.physb.2010.05.067

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