Studying the aging of Laponite suspensions using extensional rheology

Hayes, Matthew J.; Smith, M. I.

Abstract

The effect of aging on the break-up dynamics of Laponite suspensions was studied in an extensional geometry. It was found that samples of increased age undergo stronger necking at the midpoint. The thinning of samples, driven purely by motion of the plates, was compared with standard shear rheology to understand how the dynamics are related to the sample properties. The Laponite suspensions exhibit a growing stress overshoot with monotonically decreasing yield strain as they age. However, it is shown that the thinning curves in extension are only a good indicator of the sample’s static yield stress, being insensitive to its yield strain. These measurements suggest that following an initial linear visco-elastic regime, samples accumulate significant plastic deformations prior to the complete yielding of the sample. The implications of this for the importance of assessing changes to the ductile - brittle nature of samples are also discussed.

Citation

Hayes, M. J., & Smith, M. I. (2022). Studying the aging of Laponite suspensions using extensional rheology. European Physical Journal E, 45(11), Article 91. https://doi.org/10.1140/epje/s10189-022-00244-9

• Journal Article Type: Article
• Acceptance Date: Oct 31, 2022
• Online Publication Date: Nov 16, 2022
• Publication Date: Nov 16, 2022
• Deposit Date: Dec 20, 2022
• Publicly Available Date: Dec 21, 2022
• Journal: European Physical Journal E
• Print ISSN: 1292-8941
• Electronic ISSN: 1292-895X
• Peer Reviewed: Peer Reviewed
• Volume: 45
• Issue: 11
• Article Number: 91
• DOI: https://doi.org/10.1140/epje/s10189-022-00244-9
• Keywords: Yield stress, laponite, rheology, extension, ductile, brittle
• Public URL: https://nottingham-repository.worktribe.com/output/13451315
• Publisher URL: https://link.springer.com/article/10.1140/epje/s10189-022-00244-9