title: Thermal desorption gas chromatography with mass spectrometry study of outgassing from polymethacrylimide foam (Rohacell®).
abstract: Polymethacrylimide foams are used as light structural materials in outer-space devices; however, the foam closed cells contain volatile compounds that are outgassed even at low temperatures. These compounds ignite as plasmas under outer-space radiation and the intense radio-frequency fields used in communications. Since plasmas may cause spacecraft fatal events, the conditions in which they are ignited should be investigated. Therefore, qualitative and quantitative knowledge about polymethacrylimide foam outgassing should be established. Using thermogravimetric analysis, weight losses reached 3% at ca. 200°C. Thermal desorption gas chromatography with mass spectrometry detection was used to study the offgassed compounds. Using successive 4 min heating cycles at 125°C, each one corresponding to an injection, significant amounts of nitrogen (25.3%), water (2.6%), isobutylene (11.3%), tert-butanol (2.9%), 1-propanol (11.9%), hexane (25.3%), propyl methacrylate (1.4%), higher hydrocarbons (11.3%), fatty acids (2.2%) and their esters (1.3%), and other compounds were outgassed. Other compounds were observed during the main stage of thermal destruction (220-280°C). A similar study at 175°C revealed the extreme difficulty in fully outgassing polar compounds from polymethacrylimide foams by baking and showed the different compositions of the offgassed atmosphere that can be expected in the long term.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Valencia, Burjassot, Spain.
authors.forename: Enrique J
authors.initials: EJ
authors.lastname: Carrasco-Correa
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Valencia, Burjassot, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Herrero-Martínez
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Valencia, Burjassot, Spain.
authors.forename: Lina
authors.initials: L
authors.lastname: Consuegra
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, University of Valencia, Burjassot, Spain.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Ramis-Ramos
authors.affiliation: Department of Applied Physics-ICMUV, Faculty of Physics, University of Valencia, Burjassot, Valencia, Spain.
authors.forename: Rafael Mata
authors.initials: RM
authors.lastname: Sanz
authors.affiliation: Department of Applied Physics-ICMUV, Faculty of Physics, University of Valencia, Burjassot, Valencia, Spain.
authors.forename: Benito Gimeno
authors.initials: BG
authors.lastname: Martínez
authors.affiliation: Department of Communications-iTEAM, Polytechnic University of Valencia, Valencia, Spain.
authors.forename: Vicente E Boria
authors.initials: VE
authors.lastname: Esbert
authors.affiliation: European Space Agency, ESA/ESTEC, Noordwijk, The Netherlands.
authors.forename: David Raboso
authors.initials: DR
authors.lastname: García-Baquero
keywords: Outer-space materials; Outgassing; Polymethacrylimide foam; Rohacell®; Thermal desorption