SYMPOSIA PAPER Published: 01 January 1965
STP44598S

Effect of Some High-Energy Sources on Polymer-Thickened Lubricants

Source

Polymer-thickened hydraulic fluids and lubricants undergo a permanent viscosity loss with use in hydraulic and automotive equipment. Four high-energy sources, including high-temperature levels, ultrasonic irradiation, flow through a sharp-edged orifice, and gamma irradiation, have been used to produce permanent viscosity loss experimentally with fluids containing polyisobutylene, polymethacrylate, or polyester thickeners. The relative severity of these high-energy sources in producing viscosity decreases with the various polymer types is compared. Thermally induced viscosity decrease appears to differ in mechanism and relative order of severity from viscosity changes due to the other high-energy sources studied. Good correlation has been shown for the effects of mechanical shear, sonic irradiation, and gamma radiation on the relative values of viscosity loss for two polymethacrylate-thickened fluids. However, these three energy sources do not show good correlation for the polymers of different chemical structures. The possibilities of short-time mechanical shear tests are illustrated. The overall study tends to emphasize the importance of tailoring the laboratory and specification shear stability test to the severity level and type of shear involved in the end-use application.

Author Information

Klaus, E., E.
College of Engineering, Pennsylvania State University, University Park, Pa.
Tewksbury, E., J.
College of Engineering, Pennsylvania State University, University Park, Pa.
Jolie, R., M.
Socony Mobil Oil Co., Paulsboro, N. J.
Lloyd, W., A.
Cannon Instrument Co., State College, Pa.
Manning, R., E.
Cannon Instrument Co., State College, Pa.
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: D02
Pages: 45–56
DOI: 10.1520/STP44598S
ISBN-EB: 978-0-8031-6008-8
ISBN-13: 978-0-8031-6162-7