Silazane to silica

Gale A. Harvey

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NASA NTRS · 19920018042

Silazane to silica

Gale A. Harvey

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Abstract

Thin film silica and/or methyl silicone were detected on most external surfaces of the retrieved LDEF. Known sources of silicone in or on the LDEF appear inadequate to explain the ubiquitous presence of the silica and silicone films. Hexamethyldisilazane (HMDS) was used as the Challenger tile waterproofing compound for the Challenger/LDEF deployment mission. HMDS releases NH3 which depolymerizes silicone RTV's. Polyurethanes were also attacked. Much of the silica/silicone contamination of LDEF resulted from HMDS.

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Gale A. Harvey. 1992-06-01. Silazane to silica. https://ntrs.nasa.gov/citations/19920018042

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