An ESR study of the UV degradation of FEP

G. A. George; D. J. T. Hill; J. H. Odonnell; P. J. Pomery; F Rasoul

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NASA NTRS · 19920018044

An ESR study of the UV degradation of FEP

G. A. George·D. J. T. Hill·J. H. Odonnell·P. J. Pomery·F Rasoul

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Abstract

Spacecraft in low earth orbit are subjected to significant levels of high energy radiation, including ultraviolet (UV) and visible ultraviolet (VUV) wavelengths. The effects of UV radiation are enhanced over those at the surface of the earth, where the only incident wavelengths are greater than 290 nm. In low earth orbit the incident UV wavelengths extend below 290 nm into the VUV region, where the Lyman alpha-emissions of atomic hydrogen occur at 121 nm. In addition to electromagnetic radiation, in low earth orbit polymer materials may also be subjected to atomic oxygen particle radiation, which will result in direct oxidation of the polymer.

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G. A. George, D. J. T. Hill, J. H. Odonnell, P. J. Pomery, F Rasoul. 1992-06-01. An ESR study of the UV degradation of FEP. https://ntrs.nasa.gov/citations/19920018044

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