Protection of polymeric materials from atomic oxygen

The erosion of polymers and polymer-based materials (such as composites and paints) due to atomic oxygen (AO) present in the low Earth orbit (LEO) env ironment is described. Since many polymers are used extensively to fabricat e spacecraft structures and components, a method of protecting them from AO erosion was developed. This process involves surface activation of the pol ymer by UV radiation and subsequent silylation treatment to produce an oute r layer (not a coating) of silicon-dioxide based material. Experiments cond ucted in the UTIAS AO beam facility provide comparative test data for a wid e range of polymers, including composites and polyurethane paints. A predic tive model is also presented for estimating the AO erosion rates for hydroc arbon polymers based on their polymer repeat unit structure.