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Urban dumpsites are excellent sources of microbes which can biodegrade numerous materials present in waste. This study focused on the assessment of the mycodegradation potential of LDPE (Low-Density Polyethylene) by ascomycetous microfungi from urban dumpsites in Sri Lanka. Out of the collection obtained from five localities in Sri Lanka, eight species of ascomycetes, viz. Talaromyces purpureogenus (GF85), T. beijingensis (GGF03), Penicillium citrinum (GF89), Purpureocillium lilacinum (GF99), Aspergillus flavus (GF94), Aspergillus sp. (GF82), A. terreus (MMF08), and Fusarium falciforme (GF77), demonstrated mycodegradation potential based on the primary screening. All the isolates were accurately identified based on morphology, Sanger sequencing, and phylogenetic analysis of nuclear internal transcribed spacer region with 5.8 s ribosomal DNA (ITS). Among the isolates, T. purpureogenus GF85 showed a 13–17% weight reduction of LDPE. The same fungus showed evidence of remarkable ability to cause biodeterioration of LDPE by Fourier-transform infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). This study highlights the significance of extensive sampling, morphological, molecular characterisation, and comparative analysis of fungi from unexplored habitats towards developing sustainable solutions for the polyethylene waste crisis. [ABSTRACT FROM AUTHOR]

We introduce a systematic framework centered on superstructure optimization to identify the most efficient economic and environmentally friendly approach for managing plastic waste. Applying the proposed framework to low-density-polyethylene (LDPE) plastic waste, we determine that pyrolysis is the most profitable technology followed by hydroformylation to C4-C8 olefins, and the oligomerization of higher carbon olefins. Coupling the results with geographical information, the selected superstructure has the potential to improve the economics of plastic waste management by approximately $3 per kgLDPE in countries like the United States. On the other hand, the lowest CO2 emission plastic waste management uses solvent-based recycling only when there is significant degradation during mechanical recycling. When plastic waste can be recycled mechanically more than five times, the emissions in mechanical recycling are lower. These technologies collectively contribute to emissions reductions ranging from 1.5 and 3 kgCO2eq. per kgLDPE, for mechanical and solvent-based recycling, respectively. [ABSTRACT FROM AUTHOR]

Equilibrium passive sampling continues to find increasing use for performing in situ assessments and monitoring of hydrophobic organic compounds (HOCs). Although this method has been successfully used in several field studies including open surface waters and sediments, comparatively, their use in groundwater has been very limited. In this study, low-density polyethylene (LDPE) passive samplers were deployed for 80 days in three groundwater wells contaminated with polycyclic aromatic hydrocarbons (PAHs). Prior to deployment, LDPE was loaded with performance reference compounds (PRCs) consisting of deuterated PAHs and their release used to ascertain system equilibrium. Within the 80-day deployment period, LDPE-groundwater equilibrium was confirmed for PAHs with molecular weights (MWs) in the range of 178 to 228 (i.e. anthracene, chrysene). Measured freely dissolved concentrations (Cw) were between one to three orders of magnitude lower than the total filtered concentrations (Ctotal) in the studied wells. The sum of PAHs (ΣPAHs) measured based on Cw and Ctotal were 2.05, 0.07 and 29.2 μg L−1 and 197, 59.7 and 1010 μg L−1, at wells 1, 2 and 3, respectively. A separate dataset, comprising long-term (2010 to 2022) concentrations of PAHs in total (i.e., unfiltered) groundwater, is also presented to provide insight into PAH contamination levels at the assessed groundwater wells based on conventional measurement. Estimated in situ LDPE daily clearance volumes (2.34 to 27.56 Ld−1) for the target analytes were far less than the daily turnover of ground water (144 to 348 Ld−1) encountered in the wells eliminating the possibility of depletive sampling of the groundwater by the passive samplers. These results represent the first published study on the practical application of equilibrium passive sampling using LDPE for monitoring and quantitatively assessing PAHs in groundwater. Also, this work demonstrates that LDPEs are a useful tool for measuring the Cw of PAHs in groundwater, a critical contaminant in many ecological and human health risk assessments. [ABSTRACT FROM AUTHOR]

In order to suppress the damage of cable insulation caused by water tree structure formed by micro‐droplets at insulation defects in low density polyethylene (LDPE) materials under AC electric field. In this paper, the siloxane group is grafted onto LDPE by melt grafting method, and different content of comonomer styrene (St) is added to improve the grafting rate of siloxane group grafted polyethylene. The effect of St on the microscopic characteristics of LDPE grafted KH570 is studied. In order to verify the accuracy and timeliness of water tree self‐healing of grafted polymer insulation materials, the microstructure characteristics of LDPE ungrafted and grafted polymer samples are analyzed by Fourier transform infrared spectroscopy, gel content test, and differential scanning calorimeter. Second, the AC dielectric properties of LDPE ungrafted and grafted polymer samples are studied by AC breakdown experiment and space charge test. Finally, the water tree length, micropore defects, and self‐healing of the samples are observed by optical microscopy and polarization and depolarization current method, and the changes of chemical composition in the water tree area before and after aging are analyzed by infrared spectroscopy. The principle and mechanism of repairing water tree defects with grafted monomers are explained. This paper not only combines the previous research results of self‐healing materials, but also provides a new method for the preparation process of LDPE grafted polymer, which has a good research prospect in practical application. [ABSTRACT FROM AUTHOR]

The antibacterial activity of biomedical polymer materials is an important basis for their resistance to biofilm contamination as implantable medical devices. However, developing durable and stable antibacterial composites through a universal manufacturing method remains a challenge. Herein, based on an organic–inorganic synergistic antibacterial strategy, functional nanoparticles with high antibacterial performance and better polymer compatibility were prepared by combining zinc oxide nanoparticles (ZnO NPs) with quaternary ammonium compound 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (QAS), which containing siloxane group. The ZnO-QAS nanoparticles were then introduced to low-density polyethylene (LDPE) by simple melt blending to manufacture synergistic antibacterial composites. The organic–inorganic hybrid strategy significantly improved the antibacterial activity of the composites, the PE/ZnO-QAS composites possess satisfactory antibacterial efficiency of 99.9% and 99.75% against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively, and it could effectively inhibit biofilms. In addition, the functionalization of organic compound QAS provides excellent polymer compatibility for ZnO NPs, which is conducive to their uniform dispersion in LDPE, and comprehensively improves the thermal stability, mechanical properties, and crystallinity of the composites. This provides potential application value for the preparation of long-term stable antibacterial biomedical materials. [ABSTRACT FROM AUTHOR]

Biopolymer-based films are a promising alternative for the food packaging industry, in which petrochemical-based polymers like low-density polyethylene (LDPE) are commanding attention because of their high pollution levels. In this research, a biopolymer-based film made of chitosan (CS), gelatin (GEL), and glycerol (GLY) was designed. A Response Surface Methodology (RSM) analysis was performed to determine the chitosan, gelatin, and glycerol content that improved the mechanical properties selected as response variables (thickness, tensile strength (TS), and elongation at break (EAB). The content of CS (1.1% w/v), GEL (1.1% w/v), and GLY (0.4% w/v) in the film-forming solution guarantees an optimized film (OPT-F) with a 0.046 ± 0.003 mm thickness, 11.48 ± 1.42 mPa TS, and 2.6 ± 0.3% EAB. The OPT-F was characterized in terms of thermal, optical, and biodegradability properties compared to LDPE films. Thermogravimetric analysis (TGA) revealed that the OPT-F was thermally stable at temperatures below 300 °C, which is relevant to thermal processes in the food industry of packaging. The reduced water solubility (WS) (24.34 ± 2.47%) and the improved biodegradability properties (7.1%) compared with LDPE suggests that the biopolymer-based film obtained has potential applications in the food industry as a novel packaging material and can serve as a basis for the design of bioactive packaging. [ABSTRACT FROM AUTHOR]

Previous studies indicate that traditional asphalt mixtures lack the ability to withstand the stresses caused by heavy traffic volumes under high temperatures. To enhance the rutting resistance of flexible pavement under high levels of temperature and loading, extensive laboratory experiments were carried out. A 60/70 grade bitumen was used as a neat sample for comparison. The study introduced three distinct polymers, polypropylene (PP), low-density polyethylene (LDPE), and acrylonitrile butadiene styrene (ABS), at varying concentrations by weight into the neat bitumen. Initially, conventional tests were performed to evaluate the conventional properties of both the neat and modified bitumen, while aggregate tests assessed the mechanical properties of the aggregates. Subsequently, a Marshall mix design was performed to determine the optimum bitumen content (OBC) in the asphalt mixture. Finally, wheel-tracking tests were performed under a specific load and temperature to investigate the rutting behavior of the modified asphalt mixtures. The results of this comprehensive study revealed that the modified asphalt mixtures displayed improved resistance to rutting compared to the neat asphalt mixture. Furthermore, it was also observed that the LDPE exhibited a superior performance against rutting, followed by the PP and ABS. At polymer contents of 3%, 5%, and 7%, the LDPE achieved reductions in rut depth of 13%, 24%, and 33%, respectively, outperforming both PP- and ABS-modified asphalt. These findings not only enhance our understanding of asphalt behavior under diverse conditions but also highlight the potential of plastic-modified asphalt as an effective solution for mitigating rutting problems in road pavements. By incorporating plastic modifiers into asphalt mixtures, this approach aligns with the principles of sustainable construction by reducing plastic waste while improving pavement durability and performance. [ABSTRACT FROM AUTHOR]

Microplastic degradation by bacteria can degrade low-density polyethylene (LDPE). This study aimed to analyze the potential of Ambon Bay bacteria for microplastic degradation, the condition of microplastics after degradation, and identification of the potential for microplastic degradation. The results of isolation revealed as many as 20 bacterial isolates, which correlated with physicochemical conditions in the waters of Ambon Bay. Nine of them could degrade microplastics as indicated by the presence of a clear zone, namely KA1, KA2, KA3, KA4, KA5, KA9, KA10, KS6, and KS8. They were checked for biofilm formation, microplastic hydrophobicity, and percentage of microplastic weight reduction. Four isolates with the highest percentage of microplastic weight reduction on day 40 were KA1, KA2, KA3, and KA10 at 36.19%, 10.16%, 28.39%, and 17.07%, respectively. The results of LDPE microplastic degradation showed differences using field emission scanning electron microscopy-energy dispersive spectroscopy (FESEM/EDS), attenuated total reflection-fourier transform infrared (ATRFTIR), and X-ray diffraction (XRD). The bacterial isolates identified were KA1 (Bacillus cereus), KA2 (Bacillus toyonesis), KA3 (Bacillus paramycoides), and KA10 (Escherichia coli). Indigenous bacteria from the waters of Ambon Bay have the potential to degrade LDPE microplastics, which causes structural changes, decreased crystallinity, weight, and C=C groups in microplastics after degradation, with bacterial isolate KA1 identified as Bacillus cereus showing the best potential with degradation of LDPE microplastics by 36.19%. [ABSTRACT FROM AUTHOR]

Although crumb rubber (CR) modified bitumen has been widely used in bitumen pavement, the issue of storage stability has not been resolved. Waste low-density polyethylene (LDPE), a new modifier, has been introduced to improve the performance of CR-modified bitumen. However, the interaction behavior among LDPE with different ultraviolet (UV) aging degrees, crumb rubber, and bitumen is not clear, depending on the environment and source. In this study, virgin LDPE (LDPE-0)/CR blends, LDPE with 8 days UV aging (LDPE-8)/CR blends and LDPE with 64 days UV aging (LDPE-64)/CR blends were prepared by melt compounding using a twin-screw extruder and mixed with bitumen. The samples were evaluated by various tests such as dynamic shear rheometer (DSR) tests, storage stability, fluorescence microscopy, and scanning electron microscope (SEM). Then, molecular dynamics (MD) simulation was used to explore the interaction behavior between LDPE/CR blends with different UV aging degrees and bitumen. The virgin bitumen model was validated by density, radial distribution function (RDF), and glass transition temperature (Tg). The interaction behaviors were characterized based on diffusion coefficient and concentration distribution. The results showed that LDPE/CR blends were able to improve the rheological properties and storage stability, especially in LDPE-8/CR-modified bitumen. From the microscopic analysis, it was also observed that a network of LDPE/CR blends in the modified bitumen was well dispersed. Furthermore, the addition of LDPE/CR blends inhibited the aggregation behavior of the light component and slowed down the diffusion rate of bitumen molecules. The research findings provide insights for improving the storage stability of bitumen. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are one of the major substantial pollutants in the environment and are stored in sediments worldwide, especially in marine environments. This study shed light on the abundance, distribution, sources and chemical composition of MPs present in the surface sediments collected from the shelf part of the southeast coast of India, Bay of Bengal. A total of twenty-seven surface sediment samples were collected to study MPs pollution. The abundance and morphological characteristics of MPs were determined by counting using an Olympus SXZ7 stereo microscope. Raman spectroscopy analysis was used to identify the polymer type of the MPs. The average abundance of MPs in the study area is 460±275 MPs/kg in dry sediment. Regarding colour, transparent particles were predominant (46.42%), followed by blue, green, brown, etc. With respect to particle shape and size, fibres and 500-µm sized MPs are abundant. Polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polystyrene (PS) are the polymer types characterised in the study area. The higher abundance of MPs in the study area can be attenuated to human interruptions, viz., tourism, fishing and inappropriate sewage disposal in the marine environment. In addition to this, population density also plays an important role in providing MPs to the marine environment. This study provides the most valuable data to extrapolate the research for mitigating MP pollution in oceans. It also informs mankind about their disastrous activities on the marine environment, which is expected to recuperate quickly and negatively impact human health and the functionality of the marine system. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have distributed in agricultural soil. However, the effects of MPs on the growth of tobacco remain unclear. In this study, a pot experiment was conducted to evaluate the effects of linear low-density polyethylene (LLDPE) MPs at four different concentrations (0 mg·kg-1 as control, 10 mg·kg-1, 100 mg·kg-1, and 1000 mg·kg-1) on soil enzyme activity, physiological characteristics, and tobacco growth. The results showed that compared with the control, the treatments of 100 and 1000 mg·kg-1 significantly inhibited the activities of soil catalase (S-CAT) and soil sucrase (S-SC). Compared with the control, the 1000 mg·kg-1 treatment significantly altered root morphology, inhibited tobacco growth, and water content, resulting in a significant decrease in chlorophyll a content, catalase (CAT) and superoxide dismutase (SOD) activities in tobacco leaves, thereby incited a significant increase in malondialdehyde (MDA) content and peroxidase (POD) activity. Interestingly, the 10 mg·kg-1 treatment stimulated the activity of soil urease (S-UE) and root biomass. Overall, this study highlights the significant impact of MPs on soil enzymes, oxidative damage to tobacco, and inhibition of tobacco growth and development. It emphasizes the environmental risks of MPs pollution in soil, particularly for commercial crops like tobacco, and provides insights for controlling MPs abundance in the environment. Further research is needed to investigate the underlying mechanisms of MPs' effects on metabolism and genes in the soil-tobacco-microbial system. [ABSTRACT FROM AUTHOR]

Nano-plastics have been found in snow and evidence shows that they can act as nuclei. The aerosol water-uptake ability is an important property that will determine wet deposition, a potential main route for nano-plastics to fall to the ground. In this work, we measure the hygroscopicity of three nano-plastics: low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polyvinyl chloride (PVC), and a fourth compound, cellulose, with in-situ aerosol techniques via a cloud condensation nuclei counter. Cellulose is a high-molecular weight compound and a main component of commonly used paper products. Ultrafine nano-plastic particles in the range of 20 to 200 nm are explored. Nano-plastic materials LDPE, PET, and PVC form droplets more readily than cellulose nanoparticles. The high hygroscopicity of nano-plastics indicates that the nano-plastics are either oligomers or a polymer with properties for water adsorption. Furthermore, a single parameter hygroscopicity, κ, derived from different droplet activation models (Flory Huggins Köhler and Frenkel-Halsey-Hill adsorption theory) are reported. Moreover, the molecular weights of the leached oligomers are predicted by Flory Huggins Köhler theory assuming ideal polymer mixing. The observed intrinsic hygroscopicity is size-dependent, hence the adsorption-based hygroscopicity model could be applied. Nano-plastics can be incorporated into clouds, transported globally, and may also be removed from the atmosphere via wet deposition processes. The analysis of hygroscopicity help estimating the lifetime and transport of nano-plastic particles in the atmosphere. [ABSTRACT FROM AUTHOR]

In this work, the ability of calcium, magnesium, and zinc stearates to oxidative destruction of polyethylene was studied. For comparison, the samples of pure polyethylene and polyethylene with the commercial additive D2W were selected. Infrared spectroscopy data showed that samples with magnesium stearate accumulated double carbon bonds after 96 h of exposure in a climate chamber. In samples with zinc stearate, an asymmetric vibrations of COO groups disappear after 192 h of exposure in a climate chamber. All samples accumulated carbonyl groups resulting from polymer chain scission. After 96 h of aging, the sample with calcium stearate showed better oxidizing properties compared to other stearates. Mechanical test data also confirms the conclusion that the sample with calcium stearate is more susceptible to oxidative degradation among the studied stearates. [ABSTRACT FROM AUTHOR]

In the current study, a novel experimental approach was used to fabricate a biobased packaging film made of poly(butylene adipate-co-terephthalate) (PBAT) blended with cellulose (CL) and gallic acid (GA). By adding 1 wt%, 2 wt%, 3 wt%, and 5 wt% of GA to PBAT and cellulose in a 70/30 (w/w) ratio, PBAT composites have been produced using the solution casting method, with GA working as a crosslinking agent. With the use of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis/differential scanning calorimeter (TGA/DSC) analysis, the physicochemical properties of the PBAT film reinforced with CL and PBAT-CL/GA composite film were studied. Results depicted that increasing the level of GA enhanced the mechanical properties, resistance to oxygen and water vapor permeability, hydrophobicity, and antibacterial activity of the resulting films. The PBAT/CL film prepared with 5 wt% GA had higher tensile strength (33.1 MPa) in comparison to neat PBAT film (21.9 MPa). The addition of CL and GA significantly reduced the water contact angle values of the PBAT film. In addition, the PBAT composite films exhibited strong antibacterial activity, suggesting their potential application in food packaging. Food quality analysis revealed that PBAT-CL/GA film extends the shelf life of strawberries compared to the commercial low-density polyethylene film. Therefore, the use of these composite materials prolongs the freshness of perishable fruits. Current research has revealed that the PBAT-based composite film is an excellent material for food packaging. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are prevalent environmental pollutants due to their durable composition, extensive use, and improper disposal. Despite their widespread presence, rivers have received less attention in microplastic research than other water bodies. This study focused on investigating the origins, prevalence, spatial distribution, and physicochemical characteristics of microplastics in the surface waters of the Balu River, located in Dhaka, Bangladesh. Surface water samples were collected at six sampling sites of Balu River (each about 1–5 km apart) adjacent to the footwear industry, jute factory, textile mill, paper mill, agro and beverage factory, and cement plant. The study found that the average concentration of microplastics in the sampled water bodies was 102.5 ± 12.83 (items/l). Samples near the textile mill had the highest microplastic abundance (122 ± 18 items/l), while the cement plant had the lowest (58.5 ± 8 items/l). Analysis using a stereomicroscope revealed that fibers (29%), microplastics smaller than 100 µm (45%), and transparent microplastics (19%) were the most prevalent types observed in terms of shape, size, and color, respectively. Furthermore, scanning electron microscopy (SEM) observation suggested the potential for additional degradation of these microplastics into smaller particles, potentially reaching the nanoplastic scale. Additionally, Fourier transform infrared (FTIR) analysis identified 07 distinct polymer types among the microplastics: nylon (24%), polyvinyl chloride (19%), high-density polyethylene (17%), low-density polyethylene (14%), polystyrene (12%), polypropylene (7%), and nitrile (7%). The findings of this study serve as a crucial indicator of microplastic contamination, providing valuable insights into the sources and magnitude of microplastic pollution within the significant freshwater ecosystem of Balu River, Bangladesh, particularly focusing on its river systems. [ABSTRACT FROM AUTHOR]

The effect of the storage conditions of light (presence; absence) and relative humidity (50%; 75% RH) on the water content and colour of Porphyridium cruentum microalga powder was studied, then two packaging materials, low-density polyethylene (PE-LD) and metallised polyethylene terephthalate with polyethylene (PETmet/PE), were used to study their effect on the water content, colour, total carotenoids and chlorophylls contents, total phenolic content (TPC), and antioxidant activity (ABTS, DPPH, ORAC) of P. cruentum during storage at 23 °C and 50% RH. An atmosphere with 50% RH is recommended to minimise the water vapour absorption and lightness loss. In addition to the expected light protection, PETmet/PE material protected P. cruentum powder also against water absorption, contrary to PE material. There were no relevant colour changes of the microalga during storage in PETmet/PE. Regarding the total content of carotenoids and the antioxidant activity of the microalga, no significant differences were found between the biomasses stored in either packaging material. The TPC and DPPH values were practically constant during two months of storage, while ABTS and ORAC decreased more than 50% and 20%, respectively, during this time. [ABSTRACT FROM AUTHOR]

Plastic recycling facilities (PRF) are one of microplastic sources that may release into the environment. This study aims to identify the abundance and characteristics of microplastics potentially released from a PRF in Indonesia. Analysis of raw materials in the influent of the wastewater treatment plant (WWTP) showed a microplastic abundance of 485 particles/L. The dominant type of microplastic was the 2.5 μm - 5 mm size of fragmented highdensity polyethylene (HDPE). In the effluent of floating clarifier 3, the microplastic abundance detected was 98 particles/L, with low-density polyethylene (LDPE) as the dominant fragmented plastic ranging from 1.2-2.5 μm. Meanwhile, in the WWTP sludge, microplastics were identified with an abundance of 364.81 particles/kg. The microplastics found in the sludge were predominantly in the fragment form, composed of HDPE, with sizes ranging from 0.2-2.5 µm. This information is crucial for understanding the extent to which PRFs contribute to microplastic pollution in the environment. These findings emphasize the importance of implementing more effective wastewater management technologies in PRFs to reduce the release of microplastics into the environment. [ABSTRACT FROM AUTHOR]

This research investigates the microbial degradation of low-density polyethylene (LDPE) and high-density polyethylene (HDPE) plastics by Bacillus sp., Proteus sp., Pseudomonas sp., and Salmonella sp. The study employs a systematic approach, isolating microorganisms from plastic-contaminated soil and subjecting them to a series of biochemical tests for identification. The research evaluates the weight loss of LDPE and HDPE over two months, revealing varying degrees of degradation among the bacterial strains. Results suggest a potential greater susceptibility of HDPE to microbial degradation. Scanning Electron Microscopy (SEM) analysis provides high-resolution images of the plastic surface, indicating structural changes and biofilm formation during degradation. The findings highlight the unique enzymatic capabilities of each strain and underscore the significance of SEM in elucidating microbial interactions with plastics. The study prompts discussions on optimization, synergistic effects, and the identification of key enzymes in plastic degradation, emphasizing the importance of microbial strategies for waste management. Overall, this research contributes valuable insights into the potential of bacterial strains for addressing plastic pollution challenges. [ABSTRACT FROM AUTHOR]

Different ratios of wax/ethylene vinyl acetate (EVA) and wax/linear low-density polyethylene (LLDPE) blends were prepared using one-step extrusion process to investigate their potential as carrier vehicles for pattern material for investment casting. The thermal, mechanical and rheological properties were characterised. Thermal analysis was done by thermogravimetric analysis (TGA) and differential scanning calorimetry. Mechanical properties were characterised by three-point bending and thermomechanical analysis, whereas the rheological properties were characterised by oscillatory rheometry. The TGA analysis showed that the incorporation of EVA or LLDPE into wax matrix improved the thermal stability properties of the blend. This can be attributed to an enhanced phase adhesion. The melting and solidification behaviour of the blends had intermediate temperatures between wax and EVA. The EVA/wax blends displayed evident viscosity shifts as compared to the viscosity of wax. The incorporation of EVA into wax significantly altered its mechanical properties. Fourier transform infrared spectrometry for both wax/EVA and wax/LLDPE showed a predominant presence of CH2 and carbonyl group in the blend, and the mechanical properties of neat wax were improved when EVA and LLDPE were incorporated into wax. [ABSTRACT FROM AUTHOR]

Plastic pollution poses a significant threat to the environment and human health on a global level. This study aimed to investigate plastic pollution in the Harari region of Ethiopia. The result indicated that 62% of respondents demonstrated good knowledge about plastic waste, and 59% of them perceived plastic waste as harmful. Polyethylene terephthalate, high-density polyethylene, polyvinyl chloride, low-density polyethylene, polypropylene, polystyrene, and polycarbonates were the types of plastic waste identified. Being female (AOR = 1.82), aged 15–45 (AOR = 1.82), married (AOR = 1.83), and having families >3 (AOR = 2.15) were significantly positively associated with good plastic waste management practice. Being illiterate (AOR = 0.52), and having poor knowledge about plastic waste (AOR = 0.54) were significantly negatively associated with poor management practice. The findings indicated that the Harari region is prone to adverse health and environmental effects from plastic pollution. Policies restricting plastic use, training municipal waste collectors and health extension workers, and improving public awareness are indispensable. [ABSTRACT FROM AUTHOR]

This study aims to use beeswax, a readily available and cost-effective organic material, as a novel phase change material (PCM) within blends of low-density polyethylene (LDPE) and styrene-b-(ethylene-co-butylene)-b-styrene (SEBS). LDPE and SEBS act as support materials to prevent beeswax leakage. The physicochemical properties of new blended phase change materials (B-PCM) were determined using an X-ray diffractometer and an infrared spectrometer, confirming the absence of a chemical reaction within the materials. A scanning electron microscope was used for microstructural analysis, indicating that the interconnection of the structure allowed better thermal conductivity. Thermal gravimetric analysis revealed enhanced thermal stability for the B-PCM when combined with SEBS, especially within its operating temperature range. Analysis of phase change temperature and latent heat with differential scanning calorimetry showed no major difference in the melting point of the various PCM blends created. During the melting/solidification process, the B-PCMs possess excellent performance as characterized by W70/P30 (112.45 J.g−1) > W70/P20/S10 (94.28 J.g−1) > W70/P10/S20 (96.21 J.g−1) of latent heat storage. Additionally, the blends tend to reduce supercooling compared to pure beeswax. During heating and cooling cycles, the B-PCM exhibited minimal leakage and degradation, especially in blends containing SEBS. In comparison to the rapid temperature drop observed during the cooling process of W70/P30, the temperature decline of W70/P30 was slower and longer, as demonstrated by infrared thermography. The addition of LDPE to the PCM reduced melting time, indicating an improvement in the thermal energy storage reaction time to the demand. According to the obtained findings, increasing the SEBS concentration in the composite increased the thermal stability of the resulting PCM blends significantly. Despite the challenges mentioned earlier, SEBS proved to be an effective encapsulating material for beeswax, whereas LDPE served well as a supporting material. Leak tests were performed to find the ideal mass ratio, and weight loss was analyzed after multiple cycles of cooling and heating at 70 °C. The morphology, thermal characteristics, and chemical composition of the beeswax/LDPE/SEBS composite were all examined. Beeswax proves to be a highly effective phase change material for storing thermal energy within LDPE/SEBS blends. [ABSTRACT FROM AUTHOR]

In recent decades, plastic waste management has become one of the main environmental challenges for today's society. The excessive consumption of so-called single-use plastics causes continuous damage to ecosystems, and it is necessary to find alternatives to recycle these products. In this work, a mechanical and hygrothermal characterisation of novel plaster composites incorporating LDPE waste in their interior was carried out. Thus, prefabricated plasterboards have been designed with a partial replacement of the original raw material with recycled LDPE in percentages of 5–10–15% by volume. The results show how these new composites exceeded the 0.18 kN minimum breaking load in panels in all cases, while decreases in density and thermal conductivity of up to 15% and 21%, respectively, were obtained. In addition, an increase of 3.8%in thermal resistance was obtained by incorporating these new gypsum boards in lightweight façade walls through simulations. In this way, a new pathway was explored for the recovery of these wastes and their subsequent application in the construction sector. [ABSTRACT FROM AUTHOR]

In this paper, linear low-density polyethylene (LLDPE) fibers were stabilized by ultraviolet ray (UV) irradiation, which provided a new treatment method for fabricating carbon fiber precursors. LLDPE chips were blended with a photo-initiator 4-chlorobenzophenone (4-CBP) and a crosslinker 1,2-polybutadiene (1,2-PB) to obtain spun particles, and then they were melt spun into the fibers. Then, UV irradiation of the as-spun fibers was performed to obtain precursors. An orthogonal experimental design investigated the effects of the ingredient ratio LLDPE:1,2-PB and UV irradiation time on the fiber gelation. The results show that the factor's order of influence was: ingredient ratio > UV irradiation time. The fiber gelation reaches a maximum of 67.51% at a dosage ratio of LLDPE:1, 2-PB of 97:2, and a UV irradiation time of 30 min. The UV irradiation introduced the crosslinking structure of LLDPE fibers, and the melting temperature of UV-XLPE fibers shifts toward lower temperatures, and the crystal size of the fibers decreased with increasing UV irradiation time. However, longer irradiation time does not beneficially affect the gelation degree. The low cost and feasible crosslinking method in this study offer the possibility of wide application of low-cost polyethylene-based carbon fibers. [ABSTRACT FROM AUTHOR]

Fused filament fabrication (FFF) has been widely adopted due to its simplicity and cost‐effectiveness. But until now, its application materials are still limited. Polyolefin material is one of the most commonly used plastics. However, low‐density polyethylene (LDPE) is rarely used in FFF due to the inadequate strength of the filaments and the warpage of the printed parts. In this work, polystyrene (PS) is added to LDPE to obtain blend filaments. After that, the filaments are used to validate the possibility of in situ microfibrillation directly in the process. The results show that the addition of PS can significantly improve the bending strength, bending modulus, and hardness without affecting the heat resistance and crystal transition of the composite. Besides, the PS dispersed phase can form microfibers under the influence of the shear field. The formation of microfibers can significantly enhance the mechanical properties of composites. The tensile strength and Young's modulus increase by 140% and 221%, respectively. The warping deformation and surface morphology of printed parts are also improved. This study provides a new idea for utilizing low‐strength polyolefin in 3D printing and achieving performance enhancement. [ABSTRACT FROM AUTHOR]

Humans and animals encounter a summation of exposures during their lifetime (the exposome). In recent years, the scope of the exposome has begun to include microplastics. Microplastics (MPs) have increasingly been found in locations, including in animal gastrointestinal tracts, where there could be an interaction with Salmonella enterica serovar Typhimurium, one of the commonly isolated serovars from processed chicken. However, there is limited knowledge on how gut microbiomes are affected by microplastics and if an effect would be exacerbated by the presence of a pathogen. In this study, we aimed to determine if acute exposure to microplastics in vitro altered the gut microbiome membership and activity. The microbiota response to a 24 h co-exposure to Salmonella enterica serovar Typhimurium and/or low-density polyethylene (PE) microplastics in an in vitro broiler cecal model was determined using 16S rRNA amplicon sequencing (Illumina) and untargeted metabolomics. Community sequencing results indicated that PE fiber with and without S. Typhimurium yielded a lower Firmicutes/Bacteroides ratio compared with other treatment groups, which is associated with poor gut health, and overall had greater changes to the cecal microbial community composition. However, changes in the total metabolome were primarily driven by the presence of S. Typhimurium. Additionally, the co-exposure to PE fiber and S. Typhimurium caused greater cecal microbial community and metabolome changes than either exposure alone. Our results indicate that polymer shape is an important factor in effects resulting from exposure. It also demonstrates that microplastic-pathogen interactions cause metabolic alterations to the chicken cecal microbiome in an in vitro chicken cecal mesocosm. [ABSTRACT FROM AUTHOR]

Multilayered plastics are widely used in food packaging and other commercial applications due to their tailored functional properties. By layering different polymers, the multilayered composite material can have enhanced mechanical, thermal, and barrier properties compared to a single plastic. However, there is a significant need to recycle these multilayer plastics, but their complex structure offers significant challenges to their successful recycling. Ultimately, the use and recycling of these complex materials requires the ability to characterize the composition and purity as a means of quality control for both production and recycling processes. New advances and availability of low‐field benchtop 1H NMR spectrometers have led to increasing interest in its use for characterization of multicomponent polymers and polymer mixtures. Here, we demonstrate the capability of low‐field benchtop 1H NMR spectroscopy for characterization of three common polymers associated with multilayered packaging systems (low‐density polyethylene [LDPE], ethylene vinyl alcohol [EVOH], and Nylon) as well as their blends. Calibration curves are obtained for determining the unknown composition of EVOH and Nylon in multilayered packaging plastics using both the EVOH hydroxyl peak area and an observed peak shift, both yielding results in good agreement with the prepared sample compositions. Additionally, comparison of results extracted for the same samples characterized by our benchtop spectrometer and a 500‐MHz spectrometer found results to be consistent and within 2 wt% on average. Overall, low‐field benchtop 1H NMR spectroscopy is a reliable and accessible tool for characterization of these polymer systems. [ABSTRACT FROM AUTHOR]

The reliability of thermal regulation systems is crucial for ensuring the stability of condensed-mode gas-phase fluidized bed reactors (FBRs) used in the production of linear low-density polyethylene (LLDPE). However, studies reporting on the practical industrial control engineering of such reactors relying on thermal equilibrium mechanisms are scarce. This study presents a thorough analysis of a hot thermoregulating water (TRW) valve-jamming incident and interprets the related phenomena and parameter changes. The effect of the catalyst activity and variations in the liquid-phase quantities on the TRW valve action are investigated in depth, and a general explanation is provided by analyzing typical distributed control system data trends and proven deductive reasoning. Results indicate that the polymerization stability is maintained by two thermal pathways. The first pathway is related to the latent (condensate)/sensible heat (gas) extraction and polymerization heat of the materials, and the second is associated with the TRW system, specifically the cold and hot TRW branches. These pathways exhibited synergistic bidirectional effects. Finally, a series of innovative measures are proposed for internal and external operations to fully prevent and respond to TRW valve malfunctions and maintain overall polymerization stability. This study enhances the dependability of linear low-density polyethylene production through advanced process optimization utilizing the Unipol prototype and offers perspectives on system engineering for polyethylene production processes. [ABSTRACT FROM AUTHOR]

The modified atmosphere packaging films based on polyethylene nanocomposites reinforced with perlite nanoparticles were prepared using a blow molding machine. The perlite particles were first reduced to nano dimensions using an abrasive mill, then the porosity of nanoperlite was increased to improve their efficiency in absorbing ethylene gas. For this purpose, 6 normal sodium hydroxide solution at 50°C temperature was used. Finally, perlite nanoparticles were modified by polymethyl hydrogen siloxane silane compound. In each of the stages of grinding and modifying the perlite surface, the necessary tests including dynamic light diffraction test, nitrogen absorption test and ethylene gas absorption test were performed using gas chromatography method. The results showed that the size of perlite particles was reduced to 500 nm by using an abrasive mill, and the surface modification process increased the specific surface area of perlite by 10 times. Based on this, the amount of ethylene gas absorption in perlite nanoparticles with modified surface increased up to 3 times compared to normal perlite. The results of the gas chromatography test showed that the nanocomposite film based on polyethylene reinforced with 6% by weight of modified perlite nanoparticles has several times the efficiency in absorbing ethylene gas compared to the potassium permanganate sachets The results of the mechanical properties tests of nanocomposite film in comparison with pure polyethylene film showed that nanocomposite film has higher properties than pure polyethylene. The results of shelf-life tests of green tomatoes packed in nanocomposite film based on polyethylene reinforced with modified nanoperlite showed that green tomatoes can be stored for two months using the prepared modified atmosphere packaging. [ABSTRACT FROM AUTHOR]

Plastics have been consistently produced for their practicality and convenience; however, unmanaged plastics often end up in the ocean and decompose into nano-plastics through photolytic decomposition and weathering, negatively affecting marine life. This can eventually affect humans via the food chain, highlighting the need for effective solutions. Microbial biodegradation has been proposed as a solution to minimize the impact of nano-plastics on the environment, and degradation byproducts can be used in microbial metabolic pathways. In this study, 57 bacterial strains were isolated and identified from a waste treatment facility. Bacterial strains with lipase activity were selected on Tween80 agar plates. Additionally, strains capable of growing on minimal salt agar plates supplemented with low-density polyethylene (LDPE) beads were selected. Incubation in a minimal salt medium with LDPE beads as the sole carbon source led to the selection of Pseudomonas plecoglossicida SYp2123, which is capable of degrading LDPE. This strain was subjected to high cell density culture, and Fourier-transform infrared spectroscopy revealed chemical changes on the surface of LDPE beads. Additionally, field-emission scanning electron microscopy confirmed substantial biodegradation of the surface. P. plecoglossicida SYp2123 was able to degrade LDPE beads. This discovery shows that P. plecoglossicida can potentially be used as an environmentally friendly approach for tackling issues associated with polyethylene waste. [ABSTRACT FROM AUTHOR]

A multi-objective optimization (MOO) technique to produce a low-density polyethylene (LDPE) is applied to address these two problems: increasing conversion and reducing operating cost (as the first optimization problem, P1) and increasing productivity and reducing operating cost (as the second optimization problem, P2). ASPEN Plus software was utilized for the model-based optimization by executing the MOO algorithm using the tubular reactor model. The multi-objective optimization of multi-objective Bonobo optimisers (MOBO-I, MOBO-II and MOBO-III) are utilised to solve the optimization problem. The performance matrices, including hypervolume, pure diversity, and distance, are used to decide on the best MOO method. An inequality constraint was introduced on the temperature of the reactor to prevent run-away. According to the findings of the study, the MOBO-II for Problems 1 and 2 was the most effective MOO strategy. The reason is that the solution set found represents the most accurate, diversified, and acceptable distribution points alongside the Pareto Front (PF) in terms of homogeneity. The minimum operating cost, the maximum conversion and productivity obtained by MOBO-II are Mil. RM/year 114.3, 31.45 %, Mil. RM/year 545.3, respectively. [ABSTRACT FROM AUTHOR]

This study focuses on the Kadalundi estuary, Kerala's first community reserve, investigating the prevalence and impacts of microplastics on both the estuarine environment and selected fish species. This study presents the initial evidence indicating the consumption of microplastic particles by 12 commercially important edible fish species inhabiting the Kadalundi estuary. Analysis revealed significant accumulations of microplastic fibers within the surface water. In examining 12 fish species from demersal and pelagic habitats, microplastics were found in both the gastrointestinal tracts and gills. In the digestive tracts, microplastic fragments constituted the highest proportion (46%), while in the gills, microplastic fibers were dominant (52.4%). This study observed a prevalence of blue microplastics over other colors in both water and fish samples. Notably, demersal species showed a higher incidence of ingested microplastics. Polymer analysis identified Polypropylene (PP), Nylon, Low-Density Polyethylene (LDPE), Polyethylene (PE), Polypropylene isotactic (iPP), PE 1 Octene copolymer, and Rayon in water samples, while fish samples predominantly contained LDPE, PP, PE, and Nylon. Risk assessment utilizing the Polymer Hazard Index (PHI) categorized certain polymers as posing minor to moderate risks. Pollution Load Index (PLI) computations indicated moderate to high levels of microplastic contamination across various sampling sites in the estuary. Principal Component Analysis (PCA) revealed a lack of correlation between fish size and microplastic ingestion, underscoring environmental factors' influence on microplastic intake. The study emphasizes the implications of microplastic pollution on the fragile ecosystem of the Kadalundi estuary, posing potential risks to biodiversity and human health. [ABSTRACT FROM AUTHOR]

The disposal and management of waste lithium-ion batteries (LIBs) and low-density polyethylene (LDPE) plastics pose significant environmental challenges. Here we show a synergistic pyrolysis approach that employs spent lithium transition metal oxides and waste LDPE plastics in one sealed reactor to achieve the separation of Li and transition metal. Additionally, we demonstrate the preparation of nanoscale NiCo alloy@carbon nanotubes (CNTs) through co-pyrolysis of LiNi0.6Co0.2Mn0.2O2 and LDPE. The NiCo alloy@CNTs exhibits excellent catalytic activity (Eonset = ~0.85 V) and the selectivity (~90%) for H2O2 production through the electrochemical reduction of oxygen. This can be attributed to the NiCo nanoalloy core and the presence of CNTs with abundant oxygen-containing functional groups (e.g., –COOH and C–O–C), as confirmed by density function theory calculations. Overall, this work presents a straightforward and green approach for valorizing and upcycling various waste LIBs and LDPE plastics. Waste lithium-ion batteries and low-density polyethylene plastics present environmental issues. Herein, the authors demonstrate a synergistic pyrolysis approach for efficient and selective lithium extraction and upgrading of transition metal-carbon composites. [ABSTRACT FROM AUTHOR]

Microplastic pollution in soil poses a growing environmental threat with far-reaching implications for ecosystems and human health. This study systematically investigated the distribution of microplastics (MPs) across various soil depths in diverse mulched agricultural fields. Soil samples were meticulously collected at three depths (0–5, 5–10, and 10–15 cm) from five distinct agricultural regions in Bangladesh. The analysis of MPs was conducted using Fourier Transform Infrared Spectroscopy (FTIR) and a fluorescent microscope. Notably, the results unveiled no discernible depth-related trends in MP concentration, displaying ranges of 0.13 ± 0.35 to 3.53 ± 1.77; 0 to 5.53 ± 2.36; and 0 to 4.07 ± 2.28 MPs/g of soil in 0–5 cm, 5–10 cm, and 10–15 cm, respectively. The soil exhibited a spectrum of microplastic types, including High-Density Polyethylene (HDPE), Polyethylene terephthalate (PET), Polypropylene (PP), Low-Density Polyethylene (LDPE), Poly Vinyl chloride (PVC), Poly Vinyl Alcohol (PVA), Poly vinyl fluoride (PVF), and Polytetrafluoroethylene (PTFE), ranging from 0.04 ± 0.21–3.71 ± 2.36 MPs/g of soil. Particularly, the industrial agricultural area displayed the highest microplastic concentration (12.89/g of soil). Further, Principal Component Analysis identified plastic mulch and organic manure as potential sources. Despite the presence of microplastic, the estimated concentrations indicated low risks to the farming community in Bangladesh. This research provides valuable insights into microplastic distribution in agricultural soils, enhancing our understanding of this form of pollution. [ABSTRACT FROM AUTHOR]

The present study was proposed with the idea to screen and isolate efficient low-density polyethylene (LDPE) degrading novel bacterial strains from the plastic-contaminated dumping site. The identification of the bacterial isolate was performed with the help of microbiological and molecular characterization approaches. The screening of the best isolate was performed based on its growth in Bushnell-Hass broth supplemented with LDPE sheets as the sole carbon source. The molecular characterization revealed that the isolate WD4 showed a similarity with the Pseudomonas aeruginosa species. A comparative analysis of Pseudomonas aeruginosa WD4 identified in the current study with Pseudomonas putida MTCC 2445 strain was performed. The present study demonstrated that the bacterial isolate showed 9.2% degradation of LDPE films while Pseudomonas putida revealed a 6.5% weight reduction after 100 days of incubation at 37 °C. The end products of the LDPE degradation were analysed using Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC–MS). The LDPE degradation products eluted include fatty acids such as octadecanoic, hexadecanoic acid, dodecanal, and octyl palmitoleate, alkanes, and some of the unknown compounds after 100 days of microbial treatment with the isolated strain. The detailed analysis of the by-products generated in the current study indicates their contribution to the biochemical pathway of LDPE degradation. The profound scope lies in the scalability of these bacterial strains at the industrial level to combat the LDPE waste and similar plastic garbage problems, globally. [ABSTRACT FROM AUTHOR]

Featured Application: The findings from this research may have a specific and so far unique application in creating new packaged food products that are not traditionally distributed as such. The results show that the selection of proper packaging material with good thickness, transparency and permeability characteristics along with favorable storage conditions can help to preserve the antioxidant compounds of fresh-cut nettle leaves for 14 days. Green leafy vegetables are very challenging in terms of storage and preservation, while packaging in controlled conditions with the selection of appropriate polymer material is crucial for maintaining their nutritional value and quality. Various packaging materials have different gas and water vapor permeability as well as physicochemical properties that can create a specific environment inside the package, therefore affecting the chemical composition, sensory characteristics, and overall quality of packed leafy vegetables. Stinging nettle is an edible plant with a high antioxidant content, making it a valuable leafy vegetable. Therefore, this study aimed to evaluate the influence of four packaging materials (biaxially oriented polypropylene (BOPP), low-density polyethylene (LDPE), polyamide/polyethylene (PA/PE), and polylactic acid (PLA)) on the antioxidant content of packed fresh nettle leaves during 14-day storage. Ascorbic acid content was the highest after 6 days of storage, equally well preserved in all tested films, with an average of 86.74 mg/100 g fm (fresh mass). After 14 days of storage, the total phenolic content was best preserved when packed in LDPE. The content of caffeoylmalic and chlorogenic acids was the highest in LDPE after 6 days. In addition, leaves packed in LDPE after 6 days of storage had the highest content of all photosynthetic pigments. According to FRAP analysis, the antioxidant capacity was best maintained in LDPE (at the 14th day, the measured capacity was 43.61 µmol TE/g). This study shows that the type of packaging material (BOPP, LDPE, PA/PE, and PLA) and storage duration (6 and 14 days) have a great impact on the level of antioxidant compounds in the nettle leaves, where LDPE and BOPP can be highlighted as the most favorable for the preservation of total and individual phenolic compounds, photosynthetic pigments, and antioxidant capacity. [ABSTRACT FROM AUTHOR]

To fulfil the European Green Deal targets and implement a circular economy, there is an urgent need to increase recycling rates of packaging materials. However, before recycled materials can be used in food contact applications, they must meet high safety standards. According to the European Food Safety Authority (EFSA), a worst-case scenario must be applied and unknown substances must be evaluated as being potentially genotoxic. The Ames test, which detects direct DNA-reactive effects, together with chromatographic analysis is very promising to complement risk assessment. This study aims to evaluate the effectiveness of functional barriers in ten different samples, including virgin and recycled LDPE foils. FT-IR analysis did not show major differences between virgin and recycled films. Light microscopy revealed differences in quality and an increased number of particles. GC-MS analysis detected and quantified 35 substances, including eight unknowns. Using a miniaturized version of the Ames test, four of ten samples tested positive in two individual migrates up to a dilution of 12.5%. All virgin LDPE materials tested negative; however, recycled material F showed an increased mutagenic activity, with an n-fold induction up to 28. Samples with functional barriers lowered migration and reduced mutagenicity. Nonetheless, further investigations are needed to identify possible sources of contamination. [ABSTRACT FROM AUTHOR]

Four-dimensional-printed smart materials have a wide range of applications in areas such as biomedicine, aerospace, and soft robotics. Among 3D printing technologies, fused deposition molding (FDM) is economical, simple, and apply to thermoplastics. Cross-linked polyethylene (XLPE) forms a stable chemical cross-linking structure and shows good shape-memory properties, but the sample is not soluble or fusible, which makes it hard to be applied in FDM printing. Therefore, in this work, a new idea of printing followed by irradiation was developed to prepare 4D-printed XLPE. First, low-density polyethylene (LDPE) was used to print the products using FDM technology and then cross-linked by gamma irradiation was used. The printing parameters were optimized, and the gel content, mechanical properties, and shape-memory behaviors were characterized. After gamma irradiation, the samples showed no new peak in FTIR spectra. And the samples exhibited good shape-memory capabilities. Increasing the irradiation dose increased the cross-linking degree and tensile strength and improved the shape-memory properties. However, it also decreased the elongation at break, and it did not affect the crystallization or melting behaviors of LDPE. With 120 kGy of irradiation, the shape recovery and fixity ratios (Rr and Rf) of the samples were 97.69% and 98.65%, respectively. After eight cycles, Rr and Rf remained at 96.30% and 97.76%, respectively, indicating excellent shape-memory performance. [ABSTRACT FROM AUTHOR]

Catalyst‐free, radical‐based reactive processing is used to transform low‐density polyethylene (LDPE) into polyethylene covalent adaptable networks (PE CANs) using a dialkylamino disulfide crosslinker, BiTEMPS methacrylate (BTMA). Two versions of BTMA are used, BTMA‐S2, with nearly exclusively disulfide bridges, and BTMA‐Sn, with a mixture of oligosulfide bridges, to produce S2 PE CAN and Sn PE CAN, respectively. The two PE CANs exhibit identical crosslink densities, but the S2 PE CAN manifests faster stress relaxation, with average relaxation times ∼4.5 times shorter than those of Sn PE CAN over a 130 to 160 °C temperature range. The more rapid dynamics of the S2 PE CAN translate into a shorter compression‐molding reprocessing time at 160 °C of only 5 min (vs 30 min for the Sn PE CAN) to achieve full recovery of crosslink density. Both PE CANs are melt‐extrudable and exhibit full recovery within experimental uncertainty of crosslink density after extrusion. Both PE CANs are self‐healable, with a crack fully repaired and the original tensile properties restored after 30 min for the S2 PE CAN or 60 min for the Sn PE CAN at a temperature slightly above the LDPE melting point and without the assistance of external forces. [ABSTRACT FROM AUTHOR]

This document is a corrigendum for an article titled "Plastic biodegradation by in vitro environmental microorganisms and in vivo gut microorganisms of insects." The corrigendum addresses errors in the article, including an error in a section title and incorrect information in Tables 2 and 3. The corrected information is provided, and the authors state that these errors do not change the scientific conclusions of the article. The corrigendum also includes a note from the publisher stating that the claims expressed in the article are solely those of the authors and do not necessarily represent the views of the publisher or affiliated organizations. The provided document is a list of references for various scientific studies on the biodegradation of plastic by different insect larvae. The studies explore the ability of larvae from species such as Tribolium confusum, Zophobas atratus, Tenebrio molitor, Galleria mellonella, and others to degrade different types of plastics, including polystyrene and polyethylene. The research examines the effects of plastic diets on the gut microbiota of the larvae and investigates the potential for complete digestion and biodegradation of plastics. The studies provide valuable insights into the role of insects in plastic waste management and offer potential solutions for plastic pollution. [Extracted from the article]

Pyrolysis is a promising technology for transforming waste plastics (WPs) into high-value products. In the near future it will play a key role in the circular economy, as a sustainable and environmentally friendly method of managing this waste. Although the literature reports on the pyrolysis of plastics, it is focused on pure polymers. On the other hand, the state-of-the-art knowledge about the pyrolysis of mixed and contaminated WPs is still scarce. Industrial waste processing usually uses polymer mixtures containing various impurities that influence the pyrolysis process during chemical WPs recycling. In the paper the pyrolysis of three types of WPs: low density polyethylene (LDPE), polyvinyl chloride (PVC) and polyvinyl butyral (PVB) from repeated mechanical recycling of plastics, as well as their binary and ternary mixtures, is considered. The influence of particular components on the pyrolysis process is analyzed. The aim is to determine synergistic behavior of the mixtures during the pyrolysis process, which is important for increasing the efficiency and quality of the obtained bioproducts. Methods such as thermogravimetric (TG/DTG) analysis coupled with Fourier transform infrared spectroscopy (FTIR) and mass spectroscopy (MS) are used. The variations in the initial and final temperature of pyrolysis, mass loss and mass loss rate are determined. The content of PVC significantly lowers the initial temperature and mass loss and increases the final temperature. The pyrolysis of the considered mixtures shows a noticeable synergism—in the initial stage of pyrolysis up to a temperature around 450 °C, the mass loss is accelerated compared to what is predicted by simple superposition. The inhomogeneity of the mixtures as well as the waste origin causes a significant variation in the activation energy. Three main conclusions are obtained: (i) if the waste does not contain PVC, the pyrolysis is nearly complete at a temperature around 500 °C at a heating rate of 10 °C/min, whereas PVC is not fully processed even at 995 °C; (ii) the synergistic effects affect significantly the pyrolysis process by accelerating some steps and lowering the activation energy; and (iii) the presence of PVC noticeably lowers the temperature of the first stage of PVB pyrolysis. The investigation results prove that chemical recycling of mixed LDPE, PVC and PVB waste can be an effective method of plastic waste management. [ABSTRACT FROM AUTHOR]

The co-pyrolysis of polyethylene terephthalate (PET) with low-density polyethylene (LDPE) and high-density polyethylene (HDPE) was carried out in a batch steel pyrolyzer in order to convert the PET into pyrolysis oil as its pyrolysis alone resulted in wax and gases. The study also aimed to increase the aromatic content of pyrolysis oil by the interaction of degradation fragments of linear chains of LDPE and HDPE with the benzene ring of PET during the pyrolysis. The reaction conditions were optimized for a higher yield of pyrolysis oil which were found to be 500 °C pyrolysis temperature with a heating rate of 0.5 °Cs−1, 1 h reaction time and 20 g of the initial mass of polymer mixture having 20% PET, 40% LDPE and 40% HDPE. Waste aluminium particles were applied as an economical catalyst in the process. The thermal co-pyrolysis yielded 8% pyrolysis oil, 32.3 wax, 39.7 wt% gases and 20% coke while the catalytic co-pyrolysis produced 30.2% pyrolysis oil, 4.2% wax, 53.6 wt% gases and 12% coke. The fractional distillation of catalytic oil resulted in 46% gasoline range oil, 31% kerosene range oil and 23% diesel range oil. These fractions resembled the standard fuels in terms of their fuel properties as well as FT-IR spectra. The GC-MS analysis revealed that the catalytic co-pyrolysis favoured the formation of relatively short-chain hydrocarbons with olefins and isoparaffins as major components while the thermal co-pyrolysis formed long-chain paraffins. The naphthenes and aromatics were also found in higher amounts in the catalytic oil compared with the thermal oil. [ABSTRACT FROM AUTHOR]

This study focused on the investigation microplastics (MPs) with a size of ≤1.0 mm in sand samples from Thanh Phu beach, Ben Tre, Vietnam. MPs in sand from the clam beach (from 39.67 ± 6.67 to 92.00 ± 12.93 items kg−1 dried sand) were higher than those from the bathing beach (from 21.33 ± 8.76 to 51.67 ± 16.11 items kg−1 dried sand), indicating a direct contribution of MPs from coastal aquaculture. For the clam beach, MPs in surface samples (0–4 cm) were lower than in deep samples (4–6 cm). In contrast, MPs in surface samples (0–2 cm) from the bathing beach were higher than deep samples (2–5 cm). A combination of microscopy and Fourier-transform infrared spectroscopy methods confirmed that 62.5% of the representative MPs samples or 18.9% of the suspected MPs samples were plastics. Low-density polyethylene, polypropylene and polyethylene terephthalate were the largest in abundance. Further studies are needed to assess the environmental risk of MPs accumulation. [ABSTRACT FROM AUTHOR]

In order to meet the requirements of practical applications, the comprehensive performance of thermally conductive high‐voltage insulating composites is worth evaluating. Guided by the particle packing theory, spherical alumina particles with different particle size distributions were compounded and filled into low‐density polyethylene (LDPE), and the thermal conductivity (TC) and mechanical breakdown of different compound systems were systematically investigated. The results show that the particle grading design of small‐particle filled composites has better comprehensive properties than that of single‐scale or large‐particle filled composites, which proves the superiority and feasibility of particle grading design. The 110–40 wt.% composite has a higher TC (0.47 W/(m K)) compared with LDPE, while maintaining excellent insulation properties (227 kV/mm) and mechanical properties (tensile strength of 10 MPa and elongation at break of 720%). Finally, studies on the application of composite materials in the field of thermal management and ice melting of steel‐core aluminum insulated wires were applied, and both studies show good prospects for the applications of Al2O3/LDPE thermal conductive high‐voltage insulation composites. [ABSTRACT FROM AUTHOR]

Platforms are structures built by coypus for various purposes, such as reproduction, resting, and thermoregulation. In a coastal wetland of central Italy, during a study aimed at investigating the characteristics of coypu's platforms, it was recorded, for the first time worldwide, the presence of plastic in these structures. Through a transect survey, we censused 83 platforms, among which three (3.61%) were found with presence of macro- and megaplastics (polystyrene, polypropylene, and low-density polyethylene in film form; polyester, polyamide, and expanded polystyrene in fragments). Through the FTIR spectra, it was possible to highlight the degradation of the polymeric materials. To stimulate possible in-depth investigations at the level of the food chain (e.g., coypu predators, including canids) in wet habitats, we discussed possible causes and implications of plastic presence in coypus' nest structures. [ABSTRACT FROM AUTHOR]

A flexible and stretchable vitrimer was synthesized using exclusively biobased building blocks and following green chemistry principles. Epoxidized soybean oil (ESO), vanillin, the biobased diamine, Priamine®, and oleic acid were used to create a material that can replace fossil-derived, non-biodegradable packaging. Vanillin and Priamine® were used to develop a crosslinker that could react with the epoxide groups of ESO without the need for solvents, with a catalystfree synthesis that does not generate any waste or byproducts. Oleic acid was incorporated, to tune the properties of the final material, since it can react with ESO and control the crosslink density. The vitrimers produced in this work showed excellent reprocessability and recyclability. They possess the ability to be molded, and they can also strongly adhere on surfaces. Moreover, they exhibited oxygen and water vapor barrier comparable to low density polyethylene, while showing very low migration into food simulant, which position them as a promising material for flexible food and general packaging market. The vitrimers showed also the capability of biodegradation in seawater, providing a safe end of life in case of mismanagement [ABSTRACT FROM AUTHOR]

Polymer-modified bitumen undergoes phase separation during storage due to a lack of compatibility between the polymers and bitumen. However, phase separation can be minimized via the addition of various compatibilizers. This study investigated low-density polyethylene (LDPE)-modified bitumen blends at 3, 6, 9, and 12% concentration of LDPE sourced from waste plastic films. Furthermore, the combined compatibilizers (1% of maleic anhydride-grafted polyethylene (PE-g-MA) and 0.15% sulfur) were added to LDPE-modified blends. The combination of compatibilizers significantly improved the softening point and storage stability while subsequently increasing the compatibility between recycled plastics (LDPE) and bitumen. The addition of PE-g-MA and sulfur decreased the melting temperature of LDPE up to 10 °C due to the swelling of the polymers compared to blends prepared with LDPE only. Higher thermal stability was observed for LDPE blends with PE-g-MA and sulfur than for the blends with LDPE only. The major weight loss for LDPE–based blends and LDPE blends in the presence of PE-g-MA and sulfur occurred at 380–520 °C and 400–540 °C, respectively. LDPE blends in the presence of compatibilizers showed lower phase angle at higher temperatures than neat LDPE blends, suggesting that the compatibilizers tend to form a complete polymer–bitumen network. It was concluded that incorporation of both sulfur and PE-g-MA enhanced the compatibility, thermal characteristics, and rheological properties of waste plastic-modified bitumen. [ABSTRACT FROM AUTHOR]

A study was carried out on the luminescence excitation spectra and photoluminescence (PL) spectra as well as the luminescence kinetics of low-density polyethylene composites with different contents of CaGa2S4:Eu2+ phosphor filler. The phospholuminescence was attributed to the 4f65d → 4f7 transition of the Eu3+ ion and was greatest when the filler concentration was 7 vol.%. The dependence of the PL intensity on the excitation power density up to 0.3 W/cm2 was found to be linear, indicating that these phosphors can be used as visible radiation sources in various lighting systems. [ABSTRACT FROM AUTHOR]

Recently, plastic wastes are considered a main environmental problem, and many bacterial isolates were tested to biodegrade them. The low-density polyethylene (LDPE) plastic sheets were tested to be degraded by a marine bacterial consortium. The potent marine plastic degrading isolates were biochemically identified as Bacillus licheniformis, Bacillus subtilis, and Paenibacillus xylanilyticus using the BIOLOG identification system. The identification of the most potent plastic-degrading bacterium was confirmed as Bacillus licheniformis FMMA using the 16S rRNA gene sequence. This bacterial consortium was physiologically adjusted as follows: pH 7, temperature 35°C, inoculum size 4ml/ 100ml (1.0X107CFU/ ml), and an incubation period of 30 days. It led to 34.1% plastic loss of weight. The mechanical properties (maximum force and the elongation% at break) of these treated LDPE plastic sheets showed 7.49N and 112.2%, respectively, compared to that of B. licheniformis FMMA, which showed a 25.5% plastic weight loss, with maximum force and elongation% at a breakpoint of 8.9N and 114.2%, respectively. In addition, the plastic biodegradation was also estimated through a scanning electron microscopy and Fourier transform-infrared (FTIR) spectroscopy, were a great reduction in the intensity of the -CH2 peak appeared at 2900cm-1, and the disappearance of the -OH peak at 3500cm-1 was observed. [ABSTRACT FROM AUTHOR]

PE100 features excellent creep and slow crack resistance (SCG). It is common to add color masterbatch to the natural PE100 material to produce compound ready for pipe extrusion. The polyethylene base of the masterbatch is not usually PE100 and therefore can harm the creep and SCG resistance of the PE100. In this paper the effects of small contents of a linear low-density polyethylene (LLDPE) and a unimodal high-density polyethylene (uni-HDPE) on the physical and mechanical properties, specifically strain hardening modulus (SHM) and SCG resistance of a pipe grade bimodal high-density polyethylene (bi-HDPE, PE100) were investigated. Varying contents of 0, 2.5, 5, and 10 wt% of the LLDPE or uni-HDPE were blended with the bi-HDPE in either a lab single screw extruder or internal mixer to compare the effects of the mixing method. Strain hardening test, notched constant tensile load (NCTL) test, Pennsylvania notched test (PENT) were employed to study the SCG resistance. Tensile test, melt flow index (MFI), rheological measurements, scanning electron microscopy (SEM) were also used for characterizing the samples. The results showed that the addition of 2.5 and 5 wt% of LLDPE or uni-HDPE had no significant influence on the strain hardening modulus of bi-HDPE while adding 10 wt% of LLDPE or uni-HDPE resulted in 4.3 to 12.2% reduction in SHM. The blends prepared with the single screw extruder showed more deterioration in the SHM values of the final blends compared to those prepared in the internal mixer. NCTL and PENT confirmed the trend of SHM results. [ABSTRACT FROM AUTHOR]