Accession Number : ADA556178


Title :   Atomic-Oxygen Effects on POSS Polyimides in Low Earth Orbit


Descriptive Note : Journal article


Corporate Author : AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE


Personal Author(s) : Minton, Timothy K ; Wright, Michael E ; Tomczak, Sandra J ; Marquez, Sara A ; Shen, Linhan ; Brunsvold, Amy L ; Cooper, Russell ; Zhang, Jianming ; Vij, Vandana ; Guenthner, Andrew J ; Petteys, Brian J


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a556178.pdf


Report Date : 11 Jan 2012


Pagination or Media Count : 44


Abstract : Kapton polyimde is extensively used in solar arrays, spacecraft thermal blankets, and space inflatable structures. Upon exposure to atomic oxygen in low Earth orbit (LEO), Kapton is severely eroded. An effective approach to prevent this erosion is to incorporate polyhedral oligomeric silsesquioxane (POSS) into the polyimide matrix by copolymerizing POSS monomers with the polyimide precursor. The copolymerization of POSS provides Si and O in the polymer matrix on the nano level. During exposure of POSS polyimide to atomic oxygen, organic material is degraded and a silica passivation layer is formed. This silica layer protects the underlying polymer from further degradation. Laboratory and space-flight experiments have shown that POSS polyimides are highly resistant to atomic-oxygen attack, with erosion yields that may be as little as 1% those of Kapton. The results of all the studies indicate that POSS polyimide would be a space-survivable replacement for Kapton on spacecraft that operate in the LEO environment.


Descriptors :   *EARTH ORBITS , CHEMICAL PROPERTIES , ORGANIC MATERIALS , OXYGEN , POLYIMIDE RESINS , REPRINTS , THERMAL PROPERTIES


Subject Categories : Spacecraft Trajectories and Reentry


Distribution Statement : APPROVED FOR PUBLIC RELEASE