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The growing volume of plastics derived from electronic waste (e-waste) underscores the imperative for environmentally sustainable strategies for the management of this waste. In light of the paramount importance of this issue, a pilot demonstrator for the decontamination of polymers containing Brominated Flame Retardants (BFRs) has been developed. The objective is to investigate the potential for decontaminating BFR-containing polymers from e-waste via UV-visible irradiation using a rotatory laboratory pilot operating under primary vacuum conditions. This report focuses on binary model blends composed of 90 weight% (wt%) poly(Acrylo-Butadiene-Styrene) (ABS) pellets and 10 wt% Deca-Bromo-Diphenyl Ether (DBDE), which is one of the most toxic BFRs. The efficiency of the irradiation process was evaluated as a function of pellet diameter and irradiation time using Fourier Transform InfraRed spectroscopy (FTIR) and High-Resolution Laser Desorption/Ionization Mass Spectroscopy (HR-LDI-MS). As a consequence, ABS + DBDE achieved a decontamination efficiency of 97% when irradiated with pellets of less than 1 mm in diameter for a period of 4 h. Additionally, the thermal behavior of the irradiated samples was investigated through thermogravimetric analysis and differential scanning calorimetry. It was thus established that the application of UV-visible irradiation had no significant impact on the overall thermal properties of ABS. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Recycling of plastic waste from electrical and electronic equipment (EEE), containing brominated flame retardants (BFR) remains difficult due to the increasingly stringent regulations on their handling and recovery. This report deals with photodegradation in a low-pressure reactor applying UV-visible light on Decabromodiphenyl ether (DBDE or BDE-209) randomly dispersed in commercially available Poly(acrylonitrile-butadiene-styrene) (ABS) and Poly(carbonate) (PC). The aim of this study is to investigate the possibility of decomposing a BFR in plastic waste from EEE while maintaining the specifications of the polymeric materials in order to allow for their recycling. The photodegradation of the extracted BFR was monitored using infrared spectroscopy and gas chromatography coupled with mass spectroscopy. DBDE underwent rapid photodegradation during the first minutes of exposure to UV-visible light and reached degradation yields superior to 90% after 15 min of irradiation. The evaluation of polymer properties (ABS and PC) after irradiation revealed superficial crosslinking effects, which were slightly accelerated in the presence of DBDE. However, the use of a low-pressure reactor avoids large photooxidation and allowed to maintain the thermal and structural properties of the virgin polymers. [ABSTRACT FROM AUTHOR]

Decabromodiphenylether (DBDE) is a brominated flame retardant which belongs to the group of polybromodiphenylethers (PBDEs) often used as a fire resistant additive in various well known polymeric systems like polystyrene, poly(acrylonitrile-butadiene-styrene) (ABS), polypropylene, etc. This compound can be considered as a persistent organic pollutant and presents certain risks for the environment owing to the fact that it is bioaccumulable and not biodegradable. A detailed investigation, described here, was carried out on the effect of ultraviolet/visible radiation on DBDE in ABS with the aim to study the photolytic reactions of this molecule in the solid state, in order to improve the economic and ecological treatment of brominated plastic waste from waste electrical and electronic equipment (WEEE). This study presents new aspects of the photochemical degradation of DBDE/ABS systems in the solid state. The photodegradation of DBDE in ABS was followed by Fourier transform infrared spectroscopy (FTIR) as well as by thermogravimetrical analysis (TGA). Good agreement was obtained for the results of both analytical methods in terms of the overall photolysis of DBDE. [ABSTRACT FROM AUTHOR]

Decabromodiphenylether (DBDE) is a brominated flame retardant which belongs to the group of polybromodiphenylethers (PBDEs) often used as a fire resistant additive in various well known polymeric systems like polystyrene, poly(acrylonitrile-butadiene-styrene) (ABS), polypropylene, etc. This compound can be considered as a persistent organic pollutant and presents certain risks for the environment owing to the fact that it is bioaccumulable and not biodegradable. A detailed investigation, described here, was carried out on the effect of ultraviolet/visible radiation on DBDE in ABS with the aim to study the photolytic reactions of this molecule in the solid state, in order to improve the economic and ecological treatment of brominated plastic waste from waste electrical and electronic equipment (WEEE). This study presents new aspects of the photochemical degradation of DBDE/ABS systems in the solid state. The photodegradation of DBDE in ABS was followed by Fourier transform infrared spectroscopy (FTIR) as well as by thermogravimetrical analysis (TGA). Good agreement was obtained for the results of both analytical methods in terms of the overall photolysis of DBDE. [ABSTRACT FROM AUTHOR]

[Display omitted] • A large number of End-Of-Life (EOL)-Liquid Crystals Displays (LCD) (65700) was used to extract the LCs mixtures. • Dielectric measurements were carried out over a wide range of frequencies (0.1 to 106 Hz) and temperatures (100 to −20 °C). • Dielectric and electrical properties of recycled nematic LC mixtures were determined. • The frequency and temperature evolution of the spectra recorded for recycled LCs were found comparable to those of commercial LCs. The dielectric behavior and the electrical conductivity response of recycled nematic Liquid Crystals (LCs) were studied over a wide range of frequencies (0.1 to 106 Hz) and temperatures (100 to −20 °C) with a broadband dielectric spectroscopy technique. These LC mixtures were extracted from a total of 65700 End-Of-Life (EOL)-Liquid Crystals Displays (LCD) such as computers, tablets and TVs of various sizes, brands, and production years. After a stage of purification, the recycled LC blends seemed to possess similar physical properties as conventional nematic LCs. In this report, two types of anchoring of LC molecules, obtained with homeotropic or homogeneous alignment cells, were investigated. All dielectric data were analyzed with adapted models: Havriliak-Negami and Almond West formalisms for the frequency dependence of the data, as well as Arrhenius and Vogel-Fulcher-Tammann models for their temperature dependence. In this article, it is demonstrated that despite the wide variety of EOL-LCD devices used leading to a large number of LC molecules, the frequency and temperature evolution of the recorded spectra are comparable to those of commercial LC mixtures as reported in the literature. Therefore, their future reuse could be envisaged for display applications. [ABSTRACT FROM AUTHOR]

In the present work, the dielectric properties of recycled liquid crystals (LCs) (non-purified, purified, and doped with diamond nanoparticles at 0.05, 0.1, and 0.2 wt%) were investigated. The studied LC mixtures were obtained from industrial recycling of end-of-life LC displays presenting mainly nematic phases. Dielectric measurements were carried out at room temperature on a frequency range from 0.1 to 106 Hz using an impedance analyzer. The amplitude of the oscillating voltage was fixed at 1 V using cells with homogeneous and homeotropic alignments. Results show that the dielectric anisotropy of all purified samples presents positive values and decreases after the addition of diamond nanoparticles to the LC mixtures. DC conductivity values were obtained by applying the universal law of dielectric response proposed by Jonscher. In addition, conductivity of the doped LC mixtures is lower than that of the undoped and non-purified LC. [ABSTRACT FROM AUTHOR]

The present investigation focuses on analysis of swelling behavior of systems composed of linear primary alcohols and photo-chemically crosslinked poly (butyl prop-2-enoate) (PABu). For this purpose, reactive blends composed of monofunctional (n-ABu) and difunctional (1-prop-2-enoyloxyhexyl prop-2-enoate) monomers as well as a standard photoinitiator were exposed to ultraviolet-visible (UV–vis) irradiation to induce free radical crosslinking polymerization. Experimental swelling studies of the obtained optically transparent PABu networks in methanol, ethanol, propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol and heptan-1-ol were performed by gravimetric sorption measurements. Among the various models available to rationalize the swelling kinetics of these PABu-alcohol systems, the second order approach was found to agree well with the experimental data. In particular it was observed that swelling properties strongly depend on the length of the linear alkyl chain of the primary alcohols. Swelling of PABu network at equilibrium increases from methanol to butan-1-ol where it reaches a maximum and subsequently decreases from butan-1-ol to heptan-1-ol. To understand this unusual behavior, polymer-solvent solubility parameters were considered, which could not account for the swelling maximum detected in the case of butan-1-ol. Molecular simulations performed on model systems composed of a linear primary alcohol molecule set and a reproduced PABu network revealed that their mutual interaction energy times the molar mass of the alcohol show a trend very similar to that of the observed swelling behavior. Unlabelled Image • Swelling analysis of crosslinked poly(n-butylacrylate) by linear primary alcohols • Experimental data were successfully described by second-order kinetics. • Strong dependence of the swelling properties on the alkyl chain length • Development of model systems taking into account mutual interactions • Molecular simulations successfully explain experimental swelling data. [ABSTRACT FROM AUTHOR]