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arXiv · 2308.15933

Interfacial fluid rheology of soft particles

Maximilian M. Schmidt·José Ruiz-Franco·Steffen Bochenek·Fabrizio Camerin·Emanuela Zaccarelli·Andrea Scotti
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Abstract

In situ interfacial rheology and numerical simulations are used to investigate microgel monolayers in a wide range of packing fractions, $\zeta_{2D}$. The heterogeneous particle compressibility determines two flow regimes characterized by distinct master curves. To mimic the microgel architecture and reproduce experiments, an interaction potential combining a soft shoulder with the Hertzian model is introduced. In contrast to bulk conditions, the elastic moduli vary non-monotonically with $\zeta_{2D}$ at the interface, confirming long-sought predictions of reentrant behavior for Hertzian-like systems.

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Maximilian M. Schmidt, José Ruiz-Franco, Steffen Bochenek, Fabrizio Camerin, Emanuela Zaccarelli, Andrea Scotti. 2023-08-30. Interfacial fluid rheology of soft particles. https://doi.org/10.1103/physrevlett.131.258202

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