Degradation of the Polymeric Brominated Flame Retardant “Polymeric FR” by Heat and UV Exposure

Monomeric brominated flame retardants often pose risks to the environment. The new group of polymeric flame retardants is claimed to be a safer alternative due to their high molecular weight and persistence by design. Within this publication, the degradation of a commercially widely applied example of this group-the polymer "Polymeric FR"-was studied during UV irradiation and long-term exposure to heat (60 °C) for up to 36 weeks. Both treatments led to a variety of degradation products, which might have potentially adverse environmental effects and an increased mobility compared to the mother polymer. Besides identifying some of the possible degradation products (including for instance 2,4,6-tribromo-3-hydroxybenzoic acid), the degradation via UV irradiation, which yields 75 different degradation products, and via heat, which led to significantly less products, was compared. In addition, further parameters like TOC and the concentration of free bromine were studied and it was demonstrated that the used type of water (distilled, reconstituted, and rainwater) does not influence the outcome of the degradation experiments.