Soft lubrication of model hydrocolloids

de Vicente, J., Stokes, J. R. and Spikes, H. A. (2006) Soft lubrication of model hydrocolloids. Food Hydrocolloids, 20 4: 483-491. doi:10.1016/j.foodhyd.2005.04.005

Author de Vicente, J.
Stokes, J. R.
Spikes, H. A.
Title Soft lubrication of model hydrocolloids
Journal name Food Hydrocolloids   Check publisher's open access policy
ISSN 0268-005X
Publication date 2006-01-01
Year available 2006
Sub-type Article (original research)
DOI 10.1016/j.foodhyd.2005.04.005
Open Access Status Not yet assessed
Volume 20
Issue 4
Start page 483
End page 491
Total pages 9
Place of publication Oxford
Publisher Elsevier
Language eng
Subject 09 Engineering
Abstract Many food products are highly structured, complex hydrocolloids that are characterized by either a gel-like or shear thinning behaviour and are thus strongly non-Newtonian systems. Their sensory perception during use is dependent on their behaviour in very thin film conditions at high shear rates. In order to better understand their behaviour in thin films, we have formulated two kinds of solution which are typically present in real systems. We examine the lubricating properties (i.e. tribology) of thin films of structured and non-structured fluids between a hard and soft surface ('soft-EHL' lubrication), when the film thickness is of a similar size to the microstructural elements. The present work involves relating the tribology of both shear thinning polymer solutions and swollen microgel suspensions to their theological and microstructural properties in thin films and at high shear rates in the boundary, mixed and fluid film lubrication regimes. We show that the polymer solutions are typically entrained into rubbing contacts to form mixed fluid/boundary lubricating films while model yield stress fluids generate only boundary lubricating films. Soft-EHL theory satisfactorily predicts friction measurements at high entrainment speeds in full film lubrication. The microgels are found to form a confined film which minimizes contact between the surfaces, causing a lowering of the friction coefficient in the boundary-regime, while the friction in the mixed-regime is also dependent on the high-shear viscosity. (c) 2005 Elsevier Ltd. All rights reserved.
Keyword Tribology
Soft contacts
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Unknown

Document type: Journal Article
Sub-type: Article (original research)
Collections: Excellence in Research Australia (ERA) - Collection
School of Chemical Engineering Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 73 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 90 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Thu, 02 Jul 2009, 02:04:18 EST