Type de document

Études primaires

Année de publication

2016

Langue

Anglais

Titre de la revue

Journal of Occupational and Environmental Hygiene

Première page

94

Dernière page

101

Résumé

Isocyanate thermal degradation characterization by liquid chromatography coupled with electrospray tandem mass spectrometry has been performed to elucidate the methylene diphenyl diisocyanate (MDI) thermal degradation structure emitted in a generation chamber using a temperature between 50°C and 180°C to produce MDI vapors. [M+H]+ ions containing an isocyanate functional group were studied by tandem mass spectrometry. The [M+H]+ ion analyses based on the combination of full scans and precursor ion scans were useful for identifying all structures. The compounds emitted were identified and validated as a mixture of compounds containing amine and isocyanate functions. Residual MDI, methylene diphenyl amino-isocyanate, and methylene diphenyl diamine were identified. Polymerized forms of these structures were also observed because amine and isocyanate chemical functions react rapidly to polymerize. These results must be used with special care by scientists establishing sensitization diagnostics and developing sampling devices using generation chambers as they must be related to MDI behavior in workplaces. Even if pure MDI is introduced in the generation chamber, several different compounds are generated when the MDI is heated at a high temperature. This can result in some misleading interpretations for non-specific isocyanate sampling device development and sensitization diagnostics as MDI is present in the chamber with other compounds with known adverse effects.

Mots-clés

Diisocyanate de méthylène, Methylene diisocyanate, CAS 4747904, Chromatographie en phase liquide, Liquid phase chromatography, Spectrométrie de masse, Mass spectrometry

Numéro de projet IRSST

0099-4240

Télécharger

Partager

COinS