Degradation of Decabromodiphenyl Ether Dispersed in Poly (Acrylo-Butadiene-Styrene) Using a Rotatory Laboratory Pilot Under UV-Visible Irradiation.

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.

Emulsion liquid membrane technique for optimal separation of Ni (II) and Sm (III) using response surface methodology and Box-Behnken experimental setup.

This study evaluated the reliability of the emulsified liquid membrane (ELM) extraction technique for recovering and separating metals, focusing on Nickel (Ni(II)) and Samarium (Sm(III)), both used in electrochemical devices. Key contributions include determining optimal conditions for creating a stable water-in-oil (W/O) emulsion. The optimal conditions were found to be a 5-minute emulsification time, 4 wt.

New Series of Hydrogen-Bonded Liquid Crystal with High Birefringence and Conductivity.

Liquid crystals with high dielectric anisotropy, low operational thresholds, and significant birefringence (Δ) represent a key focus in soft matter research. This work introduces a novel series of hydrogen-bonded liquid crystals (HBLCs) derived from 4-n-alkoxybenzoic, 4-alkoxy-3-fluorobenzoic derivatives (nOBAF), 4-alkoxy-2,3-fluorobenzoic derivatives (nOBAFF), and 2-fluoro-4-nitrobenzoic acid. The HBLCs were characterized using Fourier transform infrared spectroscopy, and their thermal behavior was evaluated via differential scanning calorimetry.

Effect of Plasticization/Annealing on Thermal, Dynamic Mechanical, and Rheological Properties of Poly(Lactic Acid).

This study investigates the use of low molecular weight poly(ethylene glycol) (PEG) as a plasticizer for poly(lactic acid) (PLA). PLA/PEG blend films were prepared using the solvent casting method with varying mixing ratios. The films were analyzed using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and dynamic rheological analysis.

Degradation processes of brominated flame retardants dispersed in high impact polystyrene under UV-visible radiation.

In order to protect human health and the environment, several regulations have been introduced in recent years to reduce or even eliminate the use of some brominated flame retardants (BFRs) due to their toxicity, persistence and bioaccumulation. Dispersions of these BFRs in polymers are widely used for various applications. In this report, four different brominated molecules, decabromodiphenyl ether (DBDE), hexabromocyclododecane (HBCDD), decabromodiphenyl ethane (DBDPE) and tris(tribromophenoxy)triazine (TTBPT), were dispersed in the solid matrix of an industrial polymer, high impact polystyrene (HIPS).

Removal of Malachite Green by Poly(acrylamide-co-acrylic acid) Hydrogels: Analysis of Coulombic and Hydrogen Bond Donor-Acceptor Interactions.

Water pollution caused by dyes poses a significant threat to life on earth. Poly(acrylamide-co-acrylic acid) hydrogels are widely used to treat wastewater from various pollutants. This study aims to examine the removal of malachite green (MG), a harmful and persistent dye that could cause extensive environmental damage, from an aqueous solution by adjusting the initial concentration of acrylamide (AM) and the degree of copolymer crosslinking.

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

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.

Thermal Degradation Studies of Poly(2-ethyl hexyl acrylate) in the Presence of Nematic Liquid Crystals.

The thermal degradation behavior of Poly(2-ethyl hexyl hcrylate) (Poly(2-EHA)), blended with a commercially available nematic liquid crystal (LC) mixture, was investigated by thermal gravimetric analysis (TGA). Different heating rates, ranging from 5 to 200 °C/min, were applied under an inert atmosphere. Based on the TGA results, activation energies () at different conversion rates () were determined using three integral isoconversion methods: Flynn-Wall-Ozawa (FWO), Tang, and Kissinger-Akahira-Sunose (KAS).

Recycling of Plastics from E-Waste via Photodegradation in a Low-Pressure Reactor: The Case of Decabromodiphenyl Ether Dispersed in Poly(acrylonitrile-butadiene-styrene) and Poly(carbonate).

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.

Temperature Controlled Mechanical Reinforcement of Polyacrylate Films Containing Nematic Liquid Crystals.

This investigation reports on the thermomechanical properties of Poly-tripropyleneglycoldiacrylate (Poly-TPGDA)/liquid crystal (LC) blends, developed via free radical polymerization processes, which are induced by Electron Beam (EB) and Ultraviolet (UV) radiation. The EB-cured Poly-TPGDA network exhibits a higher glass transition temperature (), a higher tensile storage, and Young moduli than the corresponding UV-cured sample, indicating a lower elasticity and a shorter distance between the two adjacent crosslinking points. Above of Poly-TPGDA/LC blends, the LC behaves as a plasticizing agent, whereas, for EB-cured networks, at temperatures below , the LC shows a strong temperature dependence on the storage tensile modulus: the LC reinforces the polymer due to the presence of nano-sized phase separated glassy LC domains, confirmed by electron microscopy observations.

Development of a TiO/Sepiolite Photocatalyst for the Degradation of a Persistent Organic Pollutant in Aqueous Solution.

A clay-based TiO nanocomposite material was synthesized by a facile method, to investigate its structure and photocatalytic efficiency. The supported TiO nanoparticles were generated using a sol-gel method, and subsequently, mixed with a suspension of sepiolite. The material was recovered in powder form (Mc-80) and then calcined to properly arrange the crystal lattice of the TiO particles for use in heterogeneous photocatalysis (Mc-80-500).

A simple and reliable method for separation of mineral oil/polychlorobiphenyl mixtures.

Polychlorinated biphenyls (PCBs) were broadly applied worldwide as electrical insulators in transformers and power capacitors, due to their high dielectric constant and non-flammability. They were often added to mineral oils (MOs) and used as dielectric fluids, which are nowadays classified as hazardous waste. Indeed, the Stockholm Convention aims to eliminate the use of equipment with PCB content greater than 0.

Cleaning of Wastewater Using Crosslinked Poly(Acrylamide--Acrylic Acid) Hydrogels: Analysis of Rotatable Bonds, Binding Energy and Hydrogen Bonding.

The discharge of untreated wastewater, often contaminated by harmful substances, such as industrially used dyes, can provoke environmental and health risks. Among various techniques, the adsorption of dyes, using three-dimensional (3D) networks consisting of hydrophilic polymers (hydrogels), represents a low-cost, clean, and efficient remediation method. Three industrially used dyes, Methylene Blue, Eosin, and Rose Bengal, were selected as models of pollutants.

Dielectric Spectroscopy Analysis of Liquid Crystals Recovered from End-of-Life Liquid Crystal Displays.

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.

Extraction of indium-tin oxide from end-of-life LCD panels using ultrasound assisted acid leaching.

In this report, indium-tin-oxide (ITO)-layer extraction from end-of-life (EOL) Liquid Crystal Displays (LCDs) was discussed by sulfuric acid leaching with simultaneous application of ultrasonication on the ITO-side of glass/ITO panels, exhibiting various dimensions. Applying this technique presents several advantages compared to the traditional leaching process such as fast and controllable kinetics, high extraction yield of indium and tin, selective recovery of these two metals possible, and the opportunity to recycle the neat glass separately avoiding additional separation processes. ITO-dissolution kinetics from EOL LCD panels were investigated as function of leaching time and acidity of sulfuric acid.

Wettability modification of human tooth surface by water and UV and electron-beam radiation.

The wettability of the human tooth enamel and dentin was analyzed by measuring the contact angles of a drop of distilled water deposited on the surface. The samples were cut along the transverse and longitudinal directions, and their surfaces were subjected to metallographic mirror-finish polishing. Some samples were also acid etched until their microstructure became exposed.

Synthesis, antibacterial and QSAR evaluation of 5-oxo and 5-thio derivatives of 1,4-disubstituted tetrazoles.

A series of 1,4-disubstituted tetrazol-5-ones 3a, 5, 7, 12, 13 and 1,4-disubstituted tetrazol-5-thiones 3b, 9, 10 was synthesized and fully characterized by IR, MS, (1)H NMR and (13)C NMR. The series was evaluated for in vitro antibacterial activity against four Gram negative (Escherichia coli, Proteus mirabilis, Klebsiella pneumonia, and Pseudomonas aeruginosa) and three Gram positive (Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis) bacteria. The zone of inhibition was measured using the well-diffusion assay, and in vitro minimum inhibitory concentration (MIC) was determined by microbroth dilution assay.

Gelling and the collective dynamics in ferroelectric liquid crystals.

Dielectric spectroscopy has been applied to investigate the dynamic behaviour of a ferroelectric liquid crystal in the smectic C* and smectic A phases confined in gel matrices of a fibre like (1D) or platelet like (2D) structure. These gel matrices were obtained from semicarbazide or bis-acylurea derivatives, which self assemble because of their H-bonding motif. The confinement strongly influences the magnitude of the spontaneous polarization and the collective fluctuations of the director detected as the Goldstone-mode.

Phase diagrams of monomer and uv-cured difunctional-acrylate-nematic-liquid-crystal systems.

This paper deals with the thermal properties of systems made of the difunctional monomer 1,6-hexanedioldiacrylate (HDDA) and the low-molecular-weight liquid crystal E7. Experimental phase diagrams of uv-cured and uncured solutions of HDDA/E7 systems are established with a polarized optical microscope and a differential scanning calorimeter and the data analyzed within a theoretical formalism that combines the Flory-Huggins model of isotropic mixing and the Maier-Saupe model of nematic order. Ultraviolet-curing samples with a difunctional monomer such as HDDA leads to a crosslinked polymer network and consequently an elastic contribution to the free energy is introduced according to the Flory-Rehner theory of rubber elasticity.