title: Atomic oxygen effects on POSS polyimides in low earth orbit.
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.
authors.affiliation: Department of Chemistry and Biochemistry, Montana State University, 103 Chem/Biochem Building, Bozeman, Montana 59717, United States. tminton@montana.edu
authors.forename: Timothy K
authors.initials: TK
authors.lastname: Minton
authors.forename: Michael E
authors.initials: ME
authors.lastname: Wright
authors.forename: Sandra J
authors.initials: SJ
authors.lastname: Tomczak
authors.forename: Sara A
authors.initials: SA
authors.lastname: Marquez
authors.forename: Linhan
authors.initials: L
authors.lastname: Shen
authors.forename: Amy L
authors.initials: AL
authors.lastname: Brunsvold
authors.forename: Russell
authors.initials: R
authors.lastname: Cooper
authors.forename: Jianming
authors.initials: J
authors.lastname: Zhang
authors.forename: Vandana
authors.initials: V
authors.lastname: Vij
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Guenthner
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Petteys