Skip to main content
SHARE
Publication

The Determination of the Reaction Rates, Water Vapor Permeability, and Activation Energy for Thermal Oxidation of LDPE Films...

by Nouman Munir, Robert C Duckworth, Brian Hinderliter, Keith Lodge, Melissa Maurer-jones
Publication Type
Conference Paper
Book Title
Proceedings of 19th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors
Publication Date
Page Numbers
899 to 905
Volume
2343
Conference Name
19th International Conference on Environmental Degradation of Materials in Nuclear Power Systems - Water Reactors (EnvDeg 2019)
Conference Location
Boston, Massachusetts, United States of America
Conference Sponsor
The Mineral, Metals, & Materials Society, American Nuclear Society, Canadian Nuclear Society
Conference Date
-

To understand the mechanism of degradation of plastics under environmental degradation, thermal oxidation of LDPE thin film from a single manufacturer was studied. Oxidation was carried out in a pressure vessel with control at four temperatures( 22,50,70 and 80℃ and at 30 and 50psi oxygen pressures. Cup tests were done to determine the permeability of water vapor across the LDPE film at 60, 70, and 90⁰C. The extent of oxidation was monitored using ATR-FTIR and the carbonyl content calculated from the spectra. Bands centered at 1711 and 1735 cm-1 was determined resulted from the carbonyl stretches. A broad band at 3100-3600cm-1 is attributed to O-H stretching and the fingerprint region (<1400 cm-1) shows evidence of C-O stretches. The permeability and carbonyl content to water vapor increased with temperature, oxidation time, and oxygen pressure. We concluded the observed increase to the result of the disruption of the semi-crystalline structure of the film to produce amorphous regions within which the water vapor is more permeable. This study was a step in the direction for determining a reliable model for the degradation and eventual failure of medium-level power cables in nuclear power plants (NPPs).