Degradation of Polymeric Brominated Flame Retardants: Development of an Analytical Approach Using PolyFR and UV Irradiation

Many well-established methods for studying the degradation of brominated flame retardants are not useful when working with polymeric and water insoluble species. An example for this specific class of flame retardants is PolyFR (polymeric flame retardant; CAS No 1195978-93-8), which is used as a substituent for hexabromocyclododecane. Although it has been on the market for two years now, almost no information is available about its long time behavior in the environment. Within this study, we focus on how to determine a possible degradation of both pure PolyFR as well as PolyFR in the final insulation product, expanded polystyrene foam. Therefore, we chose UV radiation followed by analyses of the total bromine content at different time points via ICP-MS and identified possible degradation products such as 2,4,6-tribromophenol through LC-MS. These results were then linked with measurements of the adsorbable organically bound bromine and total organic carbon in order to estimate their concentrations. With respect to the obtained ¹H NMR, GPC, and contact angle results, the possibility for further degradation was discussed, as UV irradiation can influence the decomposition of molecules in combination with other environmental factors like biodegradation.