Evaluation of an ionic liquid-based epoxy after exposure on the MISSE-8 Carrier

Abstract

An ionic liquid-based epoxy was evaluated after more than two years of continual nadir space exposure on the MISSE-8 sample rack outside of the International Space Station. In addition to space radiation, atomic oxygen and vacuum space exposure the samples also experienced approximately 12,500 thermal cycles between ∼−40 °C and +40 °C. The returned samples exhibited no cracking or de-bonding from the aluminum discs to which the epoxy was initially applied; there was a slight change in color, and a miniscule variance in before-and-after weight was measured. Microscopic examination revealed some slight deformities, dimpling, and deposits on the exposed surfaces. These are put into the context of an on-going effort to develop viable carbon-fiber based composite tanks for, but not inclusively, cryogenic liquid containment. Keywords: MISSE, ISS, Ionic liquid, Epoxy