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arXiv · 2505.17539

Activity-enhanced shear thinning of flexible linear polar polymers

Arindam Panda·Roland G. Winkler·Sunil P. Singh
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Abstract

The rheological properties of tangentially propelled flexible polymers under linear shear flow are studied by computer simulations and are compared with analytical calculations. We find a significant impact of the coupled nonequilibrium active and shear forces on the polymer characteristics. The polar activity enhances shear-induced stretching along the flow direction, shrinkage in the transverse direction, and implies a strongly amplified shear-thinning behavior. The characteristic shear rate for the onset of these effects is determined by the activity. In the asymptotic limit of large activities, the shear-induced features become independent of activity, and for asymptotically large shear rates, shear dominates over activity with passive polymer behavior.

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Arindam Panda, Roland G. Winkler, Sunil P. Singh. 2025-05-23. Activity-enhanced shear thinning of flexible linear polar polymers. https://doi.org/10.1103/physreve.111.055413

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