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Evaporation rate and vapor pressure of selected polymeric lubricating oils.A recently developed ultrahigh-vacuum quartz spring mass sorption microbalance has been utilized to measure the evaporation rates of several low-volatility polymeric lubricating oils at various temperatures. The evaporation rates are used to calculate the vapor pressures by the Langmuir equation. A method is presented to accurately estimate extended temperature range evaporation rate and vapor pressure data for polymeric oils, incorporating appropriate corrections for the increases in molecular weight and the change in volatility of the progressively evaporating polymer fractions. The logarithms of the calculated data appear to follow linear relationships within the test temperature ranges, when plotted versus 1000/T. These functions and the observed effusion characteristics of the fluids on progressive volatilization are useful in estimating evaporation rate and vapor pressure changes on evaporative depletion.
Document ID
19730050176
Document Type
Conference Paper
Authors
Gardos, M. N. (Hughes Aircraft Co. Culver City, Calif., United States)
Date Acquired
August 7, 2013
Publication Date
April 1, 1973
Subject Category
MATERIALS, NONMETALLIC
Report/Patent Number
ASLE PREPRINT 73AM-1A-3
Meeting Information
Annual Meeting(Chicago, IL)
Funding Number(s)
CONTRACT_GRANT: NAS8-25318
Distribution Limits
Public
Copyright
Other