Leaching of halogen-free and brominated flame retardants from polymers - Influence of leaching parameters Submitted to Journal of Hazardous Materials

The ban and restrictions on some of the brominated flame retardants (BFRs) has led to an increase in use and production of alternatives such as halogenated free flame retardants (HFFRs). Limited information is available on the occurrence and fate of inorganic HFFRs. Inorganic HFFRs such as aluminum polyphosphinate (AlPi), melamine polyphosphate (MPP) and zincstannate (ZS), dissociate into ions in the environment and are difficult to trace back. Therefore, we studied the leachability of HFFRs from manufactured polymeric FR combinations in comparison with BFRs. Both HFFRs and BFRs leach from the polymers and may end up in the environment. Particle size, pH, porosity (adding synergist), surface structure, impact strength and strength of break are determining factors in the leaching behaviour of the FRs. Many of these parameters are related to the polymer type, which is the main parameter determining leaching behaviour. Differences in leaching behaviour between HFFRs and BFRs have been observed for the polymers polyamide (PA), polybutylene terephthalate (PBT) and epoxy resins (EPR). These polymer showed also the highest leaching properties. Almost no FRs leached from high impact polystyrene (HIPS)/polyphenylene ether (PPE/HIPS) and polycarbonate/acrylonitrile butadiene styrene (PC/ABS polymers). Therefore, no differences between HFFRs and BFRs were observed. This study contributes to a better understanding of the fate of inorganic HFFRs from polymers. In addition, it provides relevant information for reduction of the leaching of FRs from polymers.