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Durability of Intercalated Graphite Epoxy Composites in Low Earth OrbitThe electrical conductivity of graphite epoxy composites can be substantially increased by intercalating (inserting guest atoms or molecules between the graphene planes) the graphite fibers before composite formation. The resulting high strength, low density, electrically conducting composites have been proposed for EMI shielding in spacecraft. Questions have been raised, however, about their durability in the space environment, especially with respect to outgassing of the intercalates, which are corrosive species such as bromine. To answer those concerns, six samples of bromine intercalated graphite epoxy composites were included in the third Evaluation of Oxygen Interaction with Materials (EOIM-3) experiment flown on the Space Shuttle Discovery (STS-46). Changes in electrical conductivity, optical reflectance, surface texture, and mass loss for SiO2 protected and unprotected samples were measured after being exposed to the LEO environment for 42 hours. SiO2 protected samples showed no degradation, verifying conventional protection strategies are applicable to bromine intercalated composites. The unprotected samples showed that bromine intercalation does not alter the degradation of graphite-epoxy composites. No bromine was detected to have been released by the fibers allaying fears that outgassing could be disruptive to the sensitive electronics the EMI shield is meant to protect.
Document ID
Document Type
Technical Memorandum (TM)
Gaier, James R.
(NASA Lewis Research Center Cleveland,OH United States)
Davidson, Michelle L.
(Ohio State Univ. Cleveland,OH United States)
Shively, Rhonda
(Manchester Coll. North Manchester, IN United States)
Date Acquired
September 6, 2013
Publication Date
March 1, 1996
Subject Category
Composite Materials
Report/Patent Number
NAS 1.15:107157
Accession Number
Funding Number(s)
Distribution Limits
Work of the US Gov. Public Use Permitted.
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