2020/08/24 by Gavin J. Donley, P. Singh, Abhishek Shetty +1 · 5 citations
Agricultural and Biological Sciences · Chemical Engineering · Materials Science · #Polymer crystallization and properties #Polysaccharides Composition and Applications #Rheology and Fluid Dynamics Studies
paper · pdf · doi:10.1073/pnas.2003869117
openalex publication_date 2020/08/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/21
Materials that exhibit yielding behavior are used in many applications, from spreadable foods and cosmetics to direct write three-dimensional printing inks and filled rubbers. Their key design feature is the ability to transition behaviorally from solid to fluid under sufficient load or deformation. Despite its widespread applications, little is known about the dynamics of yielding in real processes, as the nonequilibrium nature of the transition impedes understanding. We demonstrate an iteratively punctuated rheological protocol that combines strain-controlled oscillatory shear with stress-controlled recovery tests. This technique provides an experimental decomposition of recoverable and unrecoverable strains, allowing for solid-like and fluid-like contributions to a yield stress material's behavior to be separated in a time-resolved manner. Using this protocol, we investigate the overshoot in loss modulus seen in materials that yield. We show that this phenomenon is caused by the transition from primarily solid-like, viscoelastic dissipation in the linear regime to primarily fluid-like, plastic flow at larger amplitudes. We compare and contrast this with a viscoelastic liquid with no yielding behavior, where the contribution to energy dissipation from viscous flow dominates over the entire range of amplitudes tested.