Non-silicone inorganic polymers based coatings for atomic oxygen protection in leo

摘要

Conventional dimethylsiloxane polymers (silicones) have a high erosion rate in atomic oxygen which make them unsuitable for long term exposure in the Low Earth Orbit (LEO) environment. Advanced silicon-oxygen backbone polymers can exhibit much lower atomic oxygen with vacuum ultraviolet (AO/VUV) erosion rates. However, there is currently a lack of space-qualified polymer coating systems available that can withstand the requirements of 30-35 years exposure in LEO. there is a need for flexible coatings stable in the LEO environment. This paper describes the performance of proprietary non-dimethylsiloxane inorganic polymers as a coating system resistant to AO/VUV. These coatings may be suitale for the protection of orgnaic materials and composites in LEO. The inorganic polymer is soluble in common organic solvents and can be applied onto a variety of substrates by inexpensive spinning, spryaing, or dip coating techniques. Kapton~R polyimide is the primary substrate used in this work, although other materials such as graphite epoxy composite can also be coated. Performance data of the proprietary coating are presented including the erosion rate in terrestrial AO/VUV tests and surface morphology by AFM before and aft AO/VUV exposure.