title: Volatile organic compounds in headspace over electrical components at 75 to 200°C - part 1. identification of constituents and emission rates.
abstract: The identity and emission rates of volatile organic compounds (VOCs) in headspace vapors over electronic components were determined at temperatures from 75 to 200°C using gas chromatography/mass spectrometry. The emission of VOCs may provide a basis to detect the onset of the overheating of electronic components in confined atmospheres near electronic bays on airplanes and submarines before smoldering or ignition. VOCs found in headspace vapors over components, including resistors, capacitors, diodes, transistors, and insulation from wires of a transformer, were composed of simple mixtures of substances with 6 to 10 carbon number from chemical families including ketones, aldehydes, substituted benzenes, alcohols, and phenols. Composition of the vapors was characteristic but not exclusive of a particular electrical component, except for phenols and methylstyrene, which were found only in a single component. Emission rates were expressed as nanogram of chemical per gram of component per minute, and increased from a low of 0.001 ng/g-min for nonanal from transformer wire at 100°C to a maximum of 2.5 ng/g-min at 150°C for isophorone from a resistor. Patterns of persistence with repeated sampling of headspace for components at 200°C over 5 hr suggested that VOCs arose from impurities in plastics rather than from thermal decomposition of the polymer.
authors.affiliation: New Mexico State University, Las Cruces, New Mexico 88003-8001, USA.
authors.forename: N D
authors.initials: ND
authors.lastname: Paz
authors.forename: J E
authors.initials: JE
authors.lastname: Rodriguez
authors.forename: G A
authors.initials: GA
authors.lastname: Eiceman
mesh_terms: D055615:Electrical Equipment and Supplies; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D016273:Occupational Exposure / Q000032:analysis*; D013696:Temperature; D014173:Transistors, Electronic; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000737:chemistry
chemical_list: D055549:Volatile Organic Compounds