Paper Number
VP17 

Session
Pre-recorded Flash Presentations (virtual)

Title
Elastic storage during flow of yield stress materials

Presentation Date and Time
All Week (Asynchronous) Any Time

Track / Room
Pre-recorded Presentation / Virtual

Authors (Click on name to view author profile)

  1. Marchand, Manon (Fribourg University, Physics Departmet)
  2. Caggioni, Marco (Procter & Gamble Company, Complex Fluid Microstructures)
  3. Trappe, Véronique (Fribourg University, Department of Physics)

Author and Affiliation Lines (in printed abstract book)
Manon Marchand1, Marco Caggioni2 and Véronique Trappe1
1Department of Physics, Fribourg University, Fribourg, Fribourg 1700, Switzerland; 2Complex Fluid Microstructures, Procter & Gamble Company, West Chester, OH 45069

Speaker / Presenter 
Marchand, Manon

Keywords
experimental methods; colloids; gels; non-Newtonian fluids; rheology methods

Text of Abstract
In a recent paper Caggioni et. al. [1] introduced a model to describe the shear rate dependent stress of yield stress fluids as a combination of elastic loading, plastic dissipation and viscous dissipation. This “three-component model” successfully describes data sets previously interpreted in terms of the Herschel-Bulkley [2] model, albeit maintaining physically meaningful fit parameters. Among others, it suggests that the shear rate dependent stress is characterized by two characteristic shear rates, the first denoting the onset to plastic dissipation and the second the onset to viscous dissipation.

In this contribution, we systematically probe the elastic strain recovered after applying a constant shear rate to dispersions of Carbopol microgels in propylene glycol. The recovered strain gives insight on the elastic energy stored at different shear rates, allowing us to identify the suggested transitions to respectively the plastic dissipation and viscous dissipation regimes.

These results corroborate the relevance of the three-component model, which we believe to be an interesting approach to further progress in the understanding of the flow behavior of yield stress fluids.

[1] Caggioni M., Trappe V., Spicer P.T., J. Rheol. 2020, 64:413
[2] Herschel, W.H., Bulkley, R. Kolloid-Zeitschrift 1926, 39, 291–300