Low-Energy Electron Effects on Tensile Modulus and Infrared Transmission Properties of a Polypyromellitimide Film.
Abstract
Infrared (IR) spectroscopy and tensile modulus testing have been used to evaluate the importance of experimental procedure on changes in properties of pyromellitic dianhydride-p,p'-oxydianiline film exposed to electron radiation. The radiation exposures were accelerated, approximate equivalents to the total dose expected for a 30-year mission in geosynchronous Earth orbit. The change in the tensile modulus depended more on the dose rate and the time interval between exposure and testing than on total dose. The IR data varied with both total dose and dose rate. A threshold dose rate existed below which reversible radiation effects on the IR spectra occurred. Above the threshold dose rate, irreversible effects occurred with the appearance of a new band. Postirradiation and in situ IR absorption bands were significantly different in that the latter were much smaller. This difference suggests that the electron radiation induced metastable, excited molecular states. jg p18
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1981
- Accession Number
- ADA303710
Entities
People
- Edward R. Long Jr.
- James E. Ferl
Organizations
- Langley Research Center