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Microscopy of Polyurea Grease

Published online by Cambridge University Press:  23 December 2020

Matthew A. Thorseth ,
Joseph D. Harris ,
Junsi Gu ,
John Cuthbert ,
Lauren Huffman ,
Kevin Capaldo  and
Zhe Jia
Matthew A. Thorseth*
Affiliation:
The Dow Chemical Company Analytical Sciences, 1897 Building, 633 Washington St, Midland, MI48640, USA
Joseph D. Harris
Affiliation:
The Dow Chemical Company Analytical Sciences, 1897 Building, 633 Washington St, Midland, MI48640, USA
Junsi Gu
Affiliation:
The Dow Chemical Company Analytical Sciences, Collegeville, PA19426, USA
John Cuthbert
Affiliation:
The Dow Chemical Company Industrial Solutions, Midland, MI48667, USA
Lauren Huffman
Affiliation:
The Dow Chemical Company Industrial Solutions, Midland, MI48667, USA
Kevin Capaldo
Affiliation:
The Dow Chemical Company Industrial Solutions, Midland, MI48667, USA
Zhe Jia
Affiliation:
The Dow Chemical Company Industrial Solutions, Lake Jackson, TX77566, USA
*
*Author for correspondence: Matthew A. Thorseth, E-mail: mathorseth@dow.com
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Abstract

Understanding the physical structure of greases can provide critical insight into improving the lubricating performance of a grease. Observation of the grease structure can be quite difficult depending on the type of grease and the length scale of the structure. Polyurea greases in previous reports have typically been examined by removal of the oil phase, which significantly changes the polyurea structure. This paper examines the effect of sample preparation conditions on the microstructure of polyurea greases. This study reveals new structures in the polyurea that have not been observed in the previous literature, including entangled fibers and nanotubes. Correlation is found between the observed polyurea microstructure coverage and grease stiffness.

Keywords

cryo-SEMgreasenanotubespolyureaTEMtomographyultramicrotomy
Type
Materials Science Applications
Information
Microscopy and Microanalysis , Volume 27 , Issue 1 , February 2021 , pp. 12 - 19
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Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press on behalf of the Microscopy Society of America

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References

Cyriac, F, Lugt, PM, Bosman, R, Padberg, CJ & Venner, CH (2016). Effect of thickener particle geometry and concentration on the grease EHL film thickness at medium speeds. Tribol Lett 61(2), 18.CrossRefGoogle Scholar
Delgado, MA, Valencia, C, Sánchez, MC, Franco, JM & Gallegos, C (2006). Influence of soap concentration and oil viscosity on the rheology and microstructure of lubricating greases. Ind Eng Chem Res 45(6), 1902–1910.CrossRefGoogle Scholar
Fan, X, Li, W, Li, H, Zhu, M, Xia, Y & Wang, J (2018). Probing the effect of thickener on tribological properties of lubricating greases. Tribol Int 118, 128–139.CrossRefGoogle Scholar
Liu, L & Sun, HW (2010). Impact of polyurea structure on grease properties. Lubr Sci 22(9), 405–413.CrossRefGoogle Scholar
Mansot, JL, Terech, P & Martin, JM (1989). Structural investigation of lubricating greases. Colloids Surf 39(4), 321–333.CrossRefGoogle Scholar
Muller, D, Matta, C, Thijssen, R, bin Yusof, MN, van Eijk, MCP & Chatra, S (2017). Novel polymer grease microstructure and its proposed lubrication mechanism in rolling/sliding contacts. Tribol Int 110, 278–290.CrossRefGoogle Scholar
Roman, C, Valencia, C & Franco, JM (2016). AFM and SEM assessment of lubricating grease microstructures: Influence of sample preparation protocol, frictional working conditions and composition. Tribol Lett 63(2), 20.CrossRefGoogle Scholar
Salomonsson, L, Stang, G & Zhmud, B (2007). Oil/thickener interactions and rheology of lubricating greases. Tribol Trans 50(3), 302–309.CrossRefGoogle Scholar
Sánchez, MC, Franco, JM, Valencia, C, Gallegos, C, Urquiola, F & Urchegui, R (2011). Atomic force microscopy and thermo-rheological characterisation of lubricating greases. Tribol Lett 41(2), 463–470.CrossRefGoogle Scholar
Shuff, PJ & Clarke, LJ (1991 a). Imaging of lubricating oil insolubles by electron microscopy. Tribol Int 24(6), 381–387.CrossRefGoogle Scholar
Shuff, PJ & Clarke, LJ (1991 b). The structure of grease via electron microscopy and image analysis. Lubr Sci 4(1), 35–50.CrossRefGoogle Scholar
Syed, R (2009). A Comprehensive Review of Lubricant Chemistry, Technology, Selection, and Design. West Conshohocken, PA: ASTM International.Google Scholar
Trent, JS, Scheinbeim, JI & Couchman, PR (1983). Ruthenium tetraoxide staining of polymers for electron microscopy. Macromolecules 16(4), 589–598.CrossRefGoogle Scholar
Walt, Svd, Schönberger, JL, Nunez-Iglesias, J, Boulogne, F, Warner, JD, Yager, N, Gouillart, E, Yu, T & scikit-image contributors (2014). scikit-image: Image processing in python. PeerJ 2, e453.CrossRefGoogle ScholarPubMed