Electron Beam Processing as a Promising Tool to Decontaminate Polymers Containing Brominated Flame Retardants

Molecules. 2023 Nov 24;28(23):7753. doi: 10.3390/molecules28237753.

Abstract

Electron Beam (EB) irradiation was utilized to decontaminate model systems of industrial polymers that contain a brominated flame retardant (BFR). Acrylonitrile-butadiene-styrene (ABS) and Polycarbonate (PC) are two types of polymers commonly found in Waste Electrical and Electronic Equipment (WEEE). In this study, these polymers were exposed to EB irradiation to degrade DecaBromoDiphenylEther (DBDE), one of the most toxic BFRs. Fourier-transform infrared spectroscopy analysis demonstrated an 87% degradation rate of DBDE for the ABS-DBDE system and 91% for the PC-DBDE system following an 1800 kGy irradiation dose. Thermal analysis using Differential Scanning Calorimetry revealed the presence of crosslinking in ABS and a minor reduction in the glass transition temperature of PC after EB processing. Polymers exhibited thermal stability after photolysis, as indicated by thermogravimetric analysis. In summary, EB irradiation had no impact on the overall thermal properties of both polymers. High-resolution mass spectrometry analysis has confirmed the debromination of both ABS-DBDE and PC-DBDE systems. Therefore, the results obtained are promising and could offer an alternative approach for removing bromine and other additives from plastic E-waste.

Keywords: acrylonitrile-butadiene-styrene; brominated flame retardants; e-waste; electron-beam processing; polycarbonate; recycling.

Grants and funding

This research was co-funded by the National Research Agency (EffPhob project 2021-2025) and the European Regional Development Fund (ERDF), in the framework of the INTERREG FWVL V program. The APC was funded by the University of Lille/France.