Infinite-shear viscosity plateau of salt-free aqueous xanthan solutions

Dakhil H, Auhl D, Wierschem A (2019)

Publication Type: Journal article

Publication year: 2019

Journal

Journal of Rheology American Institute of Physics

Book Volume: 63

Pages Range: 63-69

Journal Issue: 1

DOI: 10.1122/1.5044732

Abstract

We study aqueous xanthan solutions at shear rates up to about 105 s-1. At these shear rates, the salt-free solutions show an infinite-shear viscosity plateau. Depending on the xanthan concentration, we find two different regimes with scaling laws well known for the zero-shear viscosity of dilute and semidilute solutions: The crossover concentration is considerably higher than in the first Newtonian branch, which can be related to the orientation of the polyelectrolytes. In the second regime, the normal stress differences increase with an exponent of about 1, indicating that the polymer solution behaves like nematic liquid crystals or rigid fiber suspensions. In the first regime, the exponent is smaller suggesting that the polyelectrolytes behave more flexible.

Authors with CRIS profile

Haider Dakhil Professur für Hochdruckthermofluiddynamik und Rheologie Andreas Wierschem Professur für Hochdruckthermofluiddynamik und Rheologie

Involved external institutions

Technische Universität Berlin DE Germany (DE)

How to cite

APA:

Dakhil, H., Auhl, D., & Wierschem, A. (2019). Infinite-shear viscosity plateau of salt-free aqueous xanthan solutions. Journal of Rheology, 63(1), 63-69. https://dx.doi.org/10.1122/1.5044732

MLA:

Dakhil, Haider, D. Auhl, and Andreas Wierschem. "Infinite-shear viscosity plateau of salt-free aqueous xanthan solutions." Journal of Rheology 63.1 (2019): 63-69.

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