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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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