Materials International Space Station Experiment 6 (MISSE-6) was an experiment designed to examine the consequences of the space environment on various materials used in space-component design. USU’s contribution was comprised of approximately 180 samples that were suspended from the side of the International Space Station (ISS) for 18 months and returned to allow for pre- and post-flight comparisons. The sample with the most evident changes was a thin film of polyethylene terephthalate (PET) MylarTM coated with Vapor Deposited Aluminum (VDA). The post-flight analysis showed evidence of atomic oxygen erosion of the VDA layer, UV-induced discoloration of the polymer, and a crater created by a micrometeoroid impact. This project includes an analysis of the UV-induced discoloration and the creation of laboratory tests to simulate this discoloration. The UV tests place MylarTM samples under vacuum and then expose them to varying intensities of UV radiation. Using an array of deuterium lamps and an elliptical reflector allows for a condensed time span and a quantification of the discoloration of the polymer through comparison of the UV/Vis/NIR reflection spectra. The results from the UV simulation are used to determine the approximate time period of the UV exposure for the VDA coated MylarTM sample and in turn the erosion rate of the VDA layer. This project also includes an analysis of the impact crater and ramifications of the micrometeoroid impact.
Peterson, Kelby T., "Degradation of Space Polymers: A Case Study" (2015). Senior Theses and Projects. Paper 36.