WP6 Emerging Pollutants
Wednesday, 16 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall

(GOU-1117-830910) Emissions of volatile organic compounds from brominated flame retardant oligomers.

Gouteux, Bruno¹, Alaee, Mehran¹, Mabury, Scott², Muir, Derek¹, ¹ National Water Research Institute Environment Canada, Burlington, On, Canada² Dept of Chemistry University of Toronto, Toronto, On, Canada

ABSTRACT- Brominated flame retardants (BFR) oligomers are predicted to gain increasing market shares in the next future due mainly to their technical advantages such as heat-resistance or processing flexibility. From an environmental perspective, BFR oligomers are not likely to be released out of products like additive lower molecular weight BFR monomers since their larger structure will become more entangled in the final material. However, low molecular weight residuals, which can be monomers, by products, and/or impurities may be present in commercial BFR oligomers. Degradation products may also be formed during the complete life cycle of BFR oligomer. These compounds may have a high potential for blooming, especially under thermal stress. An experimental approach was developed to investigate this possibility for PBS-64, a brominated polystyrene oligomer; PPB-BA, a poly(pentabromobenzyl acrylate) oligomer, and BC-58, a phenoxy-terminated carbonate oligomer of tetrabromobisphenol A. BFR oligomers were heated up from ambient temperature to 100 °C in a glass flask under an inert atmosphere. The glass flask was then cooled down and rinsed with dichloromethane to collect organic compounds released by BFR oligomers. Several brominated compounds were shown to be present in sample extracts by monitoring bromide ions (m/z=79+81) using mass spectrometry in electron capture negative- ionization mode. To identify these unknown compounds, full-scan mass spectra using mass spectrometry in electron ionization mode were obtained and compared to reference mass spectra found either in the NIST MS library or in literature. For example, among the identified brominated organic compounds, di and tribromostyrene monomers were shown to be released from the PBS-64 oligomer.

Key words: BFR, polymer, thermal stress, release