Pulsed glow discharge time of flight mass spectrometry for the screening of polymer-based coatings containing brominated flame retardants

There is an increasing concern regarding the toxicity, environmental distribution and impact of organic compounds employed today as flame retardants. Along these lines, the potential of radiofrequency pulsed glow discharge (rf-PGD) time-of-flight mass spectrometry for mass spectrometric fingerprinting and quantification of brominated flame retardants (BFRs) into polymers is investigated here. Tetrabromobisphenol A was chosen as a "model" BFR compound for system optimisation and analytical characterisation purposes. After optimisation of power and pressure operation conditions of the rf-PGD, 15 W forward power and 200 Pa were chosen with the aim of attaining good sensitivity for elemental and polyatomic ions and long-term signal stability. Then, analytical performance of micro- and milli-second GD pulse regimes was compared and better detection limits were obtained using the millisecond pulse regime (a higher number of polyatomic ions was observed as well). Under the selected optimum conditions, linear calibration graphs were obtained for elemental bromine as well as for several polymer fragments. Limits of detection well below 0.1% were obtained both for elemental bromine and for the fragments investigated. Finally, a comparison of the mass spectra obtained for some polymeric samples containing different BFR compounds was carried out. The signals of polyatomic ions, related to the BFRs, can be successfully applied to the identification and discrimination among the different polymers.