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Natural fiber‐reinforced composites are gaining significant popularity for their biodegradability and eco‐friendliness. Fiber modifications and hybridization have been used to address issues like hydrophilicity and fiber inhomogeneity. However, efficient manufacturing is still a challenge for natural fiber‐reinforced polymer composites. The present study explores the potential of microwave processing of hybrid laminates composed of sisal and jute fibers. The laminates, consisting of linear low‐density polyethylene (LLDPE) as matrix and sisal and jute as reinforcement materials were subjected to microwave processing at specific power, time, frequency, and loads. Four types of laminates with different stacking sequences: sisal‐sisal‐sisal (SSS), sisal‐jute‐sisal (SJS), jute‐sisal‐jute (JSJ), and jute‐jute‐jute (JJJ) were developed. The developed composites showed ~3% void content, with the SJS and JSJ composite having the least and highest void content, respectively. The SJS composite showed the highest tensile and flexural strength of 15.27 and 20.40 MPa, respectively, out of all the configurations and an improvement of 42% and 85% over pure LLDPE. Hybrid composites having high‐strength fibers in the skin layer exhibited superior mechanical properties. Microscopic examination of the fractured specimens revealed that fiber pull‐out and fiber breakage were the primary failure mechanisms of failure. Lateral failure due to delamination between matrix and fiber was predominant with grip and gauge regions as frequent failure points. The incorporation of sisal and jute fiber reinforcement into the polymers doesn't change the thermal stability of the fabricated composites significantly. The above results show that microwave‐assisted processing is a promising method for producing natural fiber‐reinforced hybrid polymer composites. Highlights: Development of hybrid laminates using microwave energy at 2.45 GHz.The mechanism of microwave‐based processing of polymer composites has been discussed.Effect of layering sequence on mechanical and thermal properties of the developed composite.Assessment of tensile strength with morphology, flexural strength and thermo‐gravimetric analysis. [ABSTRACT FROM AUTHOR]

Background: Tomato (Lycopersicon esculentum), a valuable economic crop worldwide, often goes to waste due to improper packaging and handling. In the present study, three types of low-density polyethylene nanocomposite films containing 3% clay (Closite 20A), 3% TiO2 nanoparticles, and their combination were synthesized using melt blending method, and evaluated on the quality parameters of tomato fruit during 42 days of storage at 4 °C. Results: Transmission electron microscopy confirmed the degree of dispersion and exfoliation of the nanoparticles. The TiO2/clay-nanocomposite films exhibited notable enhancements in Young's modulus and tensile strength compared to conventional films. The addition of clay and TiO2 nanoparticles resulted in reduced permeability to CO2, O2, and water vapor. Fruits packed with clay/TiO2 nanocomposite films showed decreased ethylene production, mitigated weight loss, and maintained pH, titratable acidity, total soluble solids, and firmness. Furthermore, clay/TiO2 nanocomposite films enhanced membrane stability, decreased membrane lipid peroxidation, and enhanced catalase and ascorbate peroxidase enzyme activity in fruits. Conclusions: The relatively good exfoliation of clay nanoparticles and the proper dispersion of TiO2 nanoparticles, which were confirmed by TEM, led to an increase in mechanical and physical properties in the Clay/TiO2 nanocomposite. This film displayed more potential in maintaining the quality properties of tomato fruit during cold storage. Therefore, this film can be considered a practical solution for minimizing pathogen risks and contamination, and enhancing the overall quality of tomato fruit. [ABSTRACT FROM AUTHOR]

Polyesters, a highly promising class of circular polymers for achieving a closed‐loop sustainable plastic economy, inherently exhibit material stability defects, especially in thermal and hydrolytic instability. Here, we introduce a class of polyesters, P(4R‐BL) (R=Ph, Bu), featuring conformationally rigid 1,3‐cyclobutane rings in the backbone. These polyesters not only exhibit superior thermostability (Td,5%=376–380 °C) but also demonstrate exceptional hydrolytic resistance with good integrity even after 1 year in basic and acidic aqueous solutions, distinguishing themselves from typical counterparts. Tailoring the flexibility of the side group R enables the controlled thermal and mechanical performance of P(4Ph‐BL) and P(4Bu‐BL) to rival durable syndiotactic polystyrene (SPS) and low‐density polyethylene (LDPE), respectively. Significantly, despite their high stability, both polyesters can be effectively depolymerized into pristine monomers, establishing a circular life cycle. [ABSTRACT FROM AUTHOR]

Polyesters, a highly promising class of circular polymers for achieving a closed‐loop sustainable plastic economy, inherently exhibit material stability defects, especially in thermal and hydrolytic instability. Here, we introduce a class of polyesters, P(4R‐BL) (R=Ph, Bu), featuring conformationally rigid 1,3‐cyclobutane rings in the backbone. These polyesters not only exhibit superior thermostability (Td,5%=376–380 °C) but also demonstrate exceptional hydrolytic resistance with good integrity even after 1 year in basic and acidic aqueous solutions, distinguishing themselves from typical counterparts. Tailoring the flexibility of the side group R enables the controlled thermal and mechanical performance of P(4Ph‐BL) and P(4Bu‐BL) to rival durable syndiotactic polystyrene (SPS) and low‐density polyethylene (LDPE), respectively. Significantly, despite their high stability, both polyesters can be effectively depolymerized into pristine monomers, establishing a circular life cycle. [ABSTRACT FROM AUTHOR]

Crosslinked polyethylene (XLPE) is an important polyethylene modification material which is widely used in high-voltage direct current (HVDC) transmission systems. Low-density polyethylene (LDPE) was used as a matrix to improve the thermal and electrical properties of XLPE composites through the synergistic effect of a crosslinking agent and nanopore structure molecular sieve, TS-1. It was found that the electrical and thermal properties of the matrices were different due to the crosslinking degree and crosslinking efficiency, and the introduction of TS-1 enhanced the dielectric constants of the two matrices to 2.53 and 2.54, and the direct current (DC) resistivities were increased to 3 × 1012 and 4 × 1012 Ω·m, with the enhancement of the thermal conductivity at different temperatures. As the applied voltage increases, the DC breakdown field strength is enhanced from 318 to 363 kV/mm and 330 to 356 kV/mm. The unique nanopore structure of TS-1 itself can inhibit the injection and accumulation in the internal space of crosslinked polyethylene composites, and the pore size effect of the filler can limit the development of electron impact ionization, inhibit the electron avalanche breakdown, and improve the strength of the external applied electric field (breakdown field) that TS-1/XLPE nanocomposites can withstand. This provides a new method for the preparation of nanocomposite insulating dielectric materials for HVDC transmission systems with better performance. [ABSTRACT FROM AUTHOR]

With the increasing concern for health and safety, it is crucial to investigate how antibacterial agents demonstrate high antibacterial activity in two-phase blend systems. In this study, we prepared antibacterial films comprising a low concentration (0.2%) zinc oxide/ethylene-octene copolymer (ZnO/POE) and ZnO/linear low-density polyethylene (LLDPE) with high antibacterial activity (99.9%) and an antibacterial property value (R) of 6.9. The addition of nanometer (nano) ZnO induces the crystallization of pure materials, increasing their crystallinity and long period and significantly reducing spherulite size. Using a two-phase blending process, we achieved an antibacterial activity of (ZnO/POE)/(ZnO/LLDPE) (0.2%) of 99.9% with an R-value of 6.9, superior to the single-phase blending of POE/(ZnO/LLDPE) (0.2%) (99.0%, R = 2.0). Significantly, this difference can be attributed to the fact that nano-ZnO promotes the compatibility of POE and LLDPE in the two-phase blending process. Additionally, the two-phase blending process enhances tear strength and light transmittance compared to single-phase blending. These findings are of great significance for developing nano-ZnO-based two-phase blend antibacterial materials with low concentration and high antibacterial activity. [ABSTRACT FROM AUTHOR]

In this work, the viability of obtaining a completed recycled composite with improved toughness by the addition of ground tire rubber (GTR) waste to a linear low-density polyethylene (LLDPE)/polypropylene (PP) blend is explored. The idea of maintaining additional processing steps as low as possible, thus reducing costs, prevailed. Thus, no treatment was performed on GTR particles, and direct blending was applied. Materials were evaluated by means of mechanical and fracture behavior, in relation to their microstructure and composition. Despite of different particle content and size incorporated, no changes in crystalline structure of LLDPE and PP were observed. Tensile behavior of composites became more ductile than the LLDPE/PP blend—decrease in stiffness around 30% and increase in elongation at break up to 280%—which is directly related to the elastomeric nature of rubber particles. However, there was no clear trend between tensile parameters and particles' sizes and percentages added. On the other side, fracture tests were very sensitive to changes induced by GTR. Even though there was no adhesion expected between thermoplastic matrix and GTR, the toughness initiation parameter increased with the content of particles added, indicating that interaction occurred between composites constituents. A large improvement in toughness—between 85 and 110%—was obtained when a homogeneous 3D network of GTR particles with no agglomerated structures was achieved. The synergistic effects of GTR particle debonding and cavitation-detachment of PP nodules, with subsequent void growth, were the main mechanisms of toughness improvement. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) is one of the established thermoplastics with inherent piezoelectric characteristics. In the past two decades, a lot of work has been reported on the use of virgin Polyvinylidene fluoride thermoplastics for sensing applications. But hitherto little has been reported on 3D printing of secondary (2°) recycled Polyvinylidene fluoride as a smart energy storage device (ESD). This work is focused on exploring the possibilities for 3D printing of smart energy storage device comprising of Polyvinylidene fluoride having (melt flow index (MFI) 30 g /(10 min) as per ASTM D 1238) reinforced with MnO2, graphite, ZnCl2, and N H 4 Cl in different weight proportions to form a feedstock filament for fused deposition modeling (FDM) in the first stage. The MFI of Polyvinylidene fluoride composites reinforced with MnO2, graphite, ZnCl2, and N H 4 Cl (34.095, 8.480, 42.982, 11.807 g /(10 min) respectively) was ascertained for possible 3D printing on FDM. The results suggest that even with an acceptable MFI of prepared 2° recycled Polyvinylidene fluoride, the same was not printable. Further for possible 3D printing on FDM, low-density polyethylene (LDPE) was blended in a Polyvinylidene fluoride matrix, and successful 3D printing-based energy storage device was prepared in the second stage. The study also highlights the mechanical, and morphological properties of Polyvinylidene fluoride composites have been improved after processing with a twin-screw extruder (TSE) by using different input parameters (screw temperature (T), screw speed (S), and load (L)). Overall, the study suggests that the proportion of LDPE, MnO2, graphite, ZnCl2, and N H 4 Cl has a significant effect on the rheological, mechanical, and morphological properties. The results have been supported with scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier-transformed infrared spectroscopy (FTIR) analysis. [ABSTRACT FROM AUTHOR]

Composites synthesized from natural waste and recycled plastic is quite a promising and interesting field for scientists and polymer industries. In the present study, bio-composites based on agriculture residue Sesamum indicum L. and recycled-low density polyethylene were synthesized by extrusion and injection molding technique at a fiber loading of 10–40 wt%. Additionally, 3% of maleic anhydride grafted low density polyethylene was used as a compatibilizer. The prepared composites were irradiated at 25 kGy, 75 kGy and 125 kGy doses of gamma rays. The effects of different fiber content and gamma doses on mechanical properties were studied statistically by Design Expert software. Response surface methodology was employed to depict the interaction among various factors and optimization was done by desirability index method. Findings indicated that composites having 30% Sesamum indicum L. irradiated at 125 kGy demonstrated best mechanical properties. A significant enhancement in tensile and flexural properties of irradiated composites can be explained effectively in terms of the cross-linking effect. The fiber–matrix adhesion and modifications in composite structure was characterized by fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and X-Ray diffraction (XRD) analysis. Furthermore, thermal stability of the composites was also found to be increased. In addition, gamma-irradiated composite exhibited the highest storage modulus and a decrease in mechanical loss factor was also observed. [ABSTRACT FROM AUTHOR]

Starch blended low‐density polyethylene (LDPE) has been extensively used to produce packaging film, but it has very low mechanical properties. This work emphasises the extraction of nanosilica from rice husk as a property‐enhancing filler for producing high‐quality packaging material. Nanosilica (200 nm) was obtained by chemical treatment followed by further size reduction through cryomill. The obtained nanomaterial was found to have a high surface area (189.64 m2/g) and pore volume (.462 cc/g) with high compatibility with the other materials in the matrix. The SEM and TEM analysis indicates the uniformity in particle size of the nanomaterial with an agglomerating tendency. The X‐ray diffractometer (XRD) and fourier transform infrared spectroscopy (FTIR) analysis reveals that the obtained material is amorphous in nature. The nanomaterial is dispersed in various proportions in LDPE/starch matrix, and it is observed that the highest tensile strength (9.62 MPa) can be obtained at 1.5% nanosilica content in the matrix. A continuous increase in Young's modulus and stiffness from 372.3 to 440.12 MPa and 20 243.2 to 28 559.42 N/m, respectively, when 1.5% of nanosilica is dispersed in the biodegradable matrix. Garden soil was a better degrading medium for the sample containing 20% of starch with weight loss of 10.32% and reduction of tensile strength and tear strength values to 5.987 MPa and 99.165 N/mm respectively, in 1 year. [ABSTRACT FROM AUTHOR]

The study focusses on a low‐density polyethylene/isotactic polybutene‐1 peel system with low‐density polyethylene as matrix and isotactic polybutene‐1 as peel component sealed against itself (cohesive peel system), and on an ethylene vinyl acetate/linear low‐density polyethylene peel system with ethylene vinyl acetate as matrix and linear low‐density polyethylene as peel component sealed against polyethylene terephthalate (adhesive peel system). Due to a new approach to estimate the true fracture surface using 3D reconstruction, it was possible to determine the true adhesive energy release rate, especially for cohesive peel systems. This enables a direct comparison of the fracture mechanics parameters determined from both types of peel systems. The results reveal that the recipe has a distinct influence on the peel behavior. An increasing amount of the used peel component leads in any case to a decrease of the peel force as well as of the energy release rate for both, sealed adhesive and cohesive peel systems. Using application engineering examples generalizable relationships between structure and properties of peel systems could be estimated and the structure sensitivity of the fracture mechanical parameters could be proven. [ABSTRACT FROM AUTHOR]

Pyrolysis behaviors of polypropylene (PP), low-density polyethylene (LDPE), and their mixtures are investigated by Thermal Gravimetric Analysis (TGA) under varying heating rates to research the co-pyrolysis kinetic and synergistic effect. Model-free methods (Flynn-Wall-Ozawa method, Kissinger-Akahira-Sunose method, and Starink method) and model-fitting techniques (Malek method, Coats-Redfern method) were utilized to determine key kinetic parameters. The average activation energy are 224.69–225.19 kJ/mol for PP, 186–188.5 kJ/mol for LDPE, 195.64–197.48 kJ/mol for PP/LDPE composites. Model-fitting analysis was employed to elucidate the thermal pyrolysis mechanisms. For PP and LDPE, the A3/2 mechanism was found to be the governing pathway, whereas the PP/LDPE blends exhibited the A1 mechanism. Subsequently, compensation effect equations were derived to elucidate the synergistic interactions between PP and LDPE during co-pyrolysis process. The co-pyrolysis of PP and LDPE mixtures exhibit a lower pyrolysis temperature compared to the individual materials. Furthermore, the activation energy and pre-exponential factor results indicate a promotion effect in the early stage and an inhibiting effect in the later stage of the pyrolysis process. [ABSTRACT FROM AUTHOR]

Bio-polybutylene succinate (PBS) is a biodegradable polymer obtained from renewable feedstock having physical–mechanical properties like traditional low-density polyethylene (LDPE). PBS is employed by many manufacturing sectors, from biomedical to agri-food and cosmetics. Although some studies have already evaluated the resistance of PBS to photodegradation caused by natural outdoor solar exposure (UVA-UVB), a systematic study on the resistance to degradation caused by exposure to UVC rays, which is the subject of this study, has not yet been carried out. PBS was exposed to UVC either neat or filled with 2% carbon black (CB). Mechanical and physical characterization (tensile, hardness, calorimetry, contact angle, morphology, and surface roughness analyses) indicates that the bulk and surface properties of the polymer matrix changes after exposure to UVC radiations, due to a severe degradation. However, the presence of carbon black compensates for the degradation phenomenon. Because UVC rays are used for the sterilization process, necessary in applications such as biomedical, cosmetic, pharmaceutical, food, and other products, a comparison of the protocol used in this paper with the literature's data has been reported and discussed. [ABSTRACT FROM AUTHOR]

A series of strategies are investigated, which allow internally plasticized polylactide (PLA)‐polyether block copolymers to be effectively melt‐processed through blown film extrusion in the semi‐technical scale. Among the strategies presented are the use of tris(nonylphenyl) phosphite (TNPP) as a chain extender during the ring opening polymerization (ROP) of lactide and the application of ε‐caprolactone (CL) as a plasticizing comonomer. The produced films have a significantly higher flexibility than pure PLA films and are in a comparable range to the flexibility of fossil‐based, film‐grade low‐density polyethylene (LDPE) films. [ABSTRACT FROM AUTHOR]

The present work explores the shear and extensional rheology of immiscible multi-micro/nanolayered systems comprising low-density polyethylene (LDPE) paired with polystyrene (PS) and polycarbonate (PC) obtained from forced-assembly multilayer coextrusion. Firstly, miscible multilayer references based on LDPE/LLDPE layers were prepared with their miscibility characterized by shear and elongational measurements. Their strain hardening behaviors were found to be intricately linked to the number of layers and confinement. Secondly, for immiscible LDPE/PS and LDPE/PC multilayers with symmetric (50/50) and asymmetric (10/90) compositions, negative deviation of complex viscosities from neat polymers was highlighted because of the heightened confinement of LDPE chains by PS or PC and reduced entanglements at polymer–polymer interfaces. Intriguingly, LDPE/PC systems exhibited no strain hardening irrespective of layer configuration, while the geometric confinement imposed by PS layers facilitated interactions between single chains with long-chain branching (LCB), leading to strain hardening under specific conditions. Furthermore, the extensional viscosities were predicted using the Macosko model (C.W. Macosko et al. Journal of Rheology. 63 2019), accurately describing the behavior of 1024 layered films for both asymmetric (10/90) LDPE/PS and LDPE/PC systems, but not for 32 layers due to a limited number of interfaces. This study provides insights into quantifying interfacial tension properties in micro/nano-layered systems with high mismatched viscoelastic polymers, shedding light on their strain hardening properties in the presence of increased interfacial area. [ABSTRACT FROM AUTHOR]

Plastic pollution is a rising environmental issue, with millions of tons of plastic debris collecting in the world's seas and on its shores. Hyperspectral imaging (HSI) has become increasingly widely used as a more precise approach that can identify targets in remote sensing aquatic missions. The interference from other beach materials, and the need for proper identification of litter types can make identifying dumped plastics on sand-surrounded beaches challenging. This study lays the groundwork for a physical laboratory setting for images captured by a hyperspectral (HS) imager. The suggested testing setup included the development of a fluorescence signature for the target theater of operations (low-density polyethylene (LD-PE) and wood surrounded by sand) for detecting polymers in a simulated beach environment using the laser-induced fluorescence (LIF) approach. Initially using broadband-spectrum light, strong sample diffuse reflectance contrast is observed in the imaging at wavelengths between 400 and 460 nm. Next, a dedicated LIF system for plastic litter discovery was developed using an ultraviolet (UV) laser source. Initial findings show that there is a distinct fluorescence signal for plastics at 450 nm and at 750 nm for wood. Our pilot studies support current efforts to determine the optimum spectral signature that these polymers will appear with clarity on shorelines using an inexpensive imagery combined with our UV LIF approach, which may have an impact on applications for the detection of beach pollution. The knowledge gained from this study can be used to construct reliable aerial conventional cameras for plastic waste environmental monitoring and management. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to produce a healthier, convenient and traditional ready-to-eat (RTE) snack option with increased nutritional value, using spent hen meat, dietary fibre (DF) and simple technological methods. The product was designed to be stable without refrigeration and be easily adoptable by local self-help groups, rural women and youth and entrepreneurs in urban and semi-urban areas. Design/methodology/approach: Conventional binder used for making snacks, i.e. rice flour was partially replaced by different sources of antioxidant DFs, i.e. oat flour (T1 – 10%), finger millet flour (T2 – 5%) and amaranth flour (T3 –15%) to prepare spent hen snack sticks (SHSS). The snacks were then packaged in low density polyethylene (LDPE) pouches and evaluated for their storage stability at ambient temperature for a period of 35 days. Their physico-chemical, sensory and microbiological quality was evaluated at a regular interval of 7 days. The proximate composition of developed SHSS was compared to commercially available snack products (chakli/murukku – snacks without meat). Findings: The fibre-enriched SHSS showed significant improvement in nutritive value, as they contained more fibre (p = 0.001) and protein (p = 0.029) than control SHSS. When compared to commercially available snack product SHSS showed three-fold significant increase in protein (p = 0.000) and ash content (p = 0.001) and only 11%–12% total fat as compared to 31% fat in the market-available product. The most acceptable treatment in terms of overall sensory quality and nutritional aspects was T3; however, T2 was more shelf-stable during the storage period. The study showed that fibre-enriched snacks can be stored at ambient temperature for up to 35 days without substantial loss in physico-chemical, sensory and microbial quality. Hence, substituting rice flour with DFs can lead to the development of products with better sensory attributes and improved functionality. Social implications: The simplicity of the product in terms of composition, machinery and low production costs makes it an easily adoptable one by small-scale entrepreneurs, especially those belonging to semi-urban areas. Originality/value: Incorporation of spent hen meat, a relatively cheap but abundant source of protein, in RTE products can serve as an effective way to alleviate protein malnutrition, whereas addition of fibre further improves the functionality of the product. The methodology can be easily taken up by small-scale entrepreneurs and create a market for snack-based functional meat products. [ABSTRACT FROM AUTHOR]

The aim of the study is to investigate the leaching of fluorescent dissolved organic matter (fDOM) from microplastics. In addition, this study identifies the connection between fDOM and microplastics in the aquatic environment. Three‐dimensional excitation–emission matrix identified five fluorophores, that is, peak A, M, T, Tuv, and Wuv, and the parallel factor analysis modeling identified five components, that is, tryptophan‐like, p‐hydroxy acetophenone, humic acid (C‐like), detergent‐like, and fulvic acid (M‐like) in the urban surface water. Mimic experiments using commonly used synthetic plastic (like microplastics) in Mili‐Q water under solar radiation and dark environments demonstrate the release of fDOM from plastic. Two fluorophore peaks were observed at Ex/Em = 250/302 nm and Ex/Em = 260/333 nm for the expanded polystyrene plastic polymer and one fluorophore peak at Ex/Em = 260/333 nm for the low‐density polyethylene. Fluorophore and component intensity exhibited notable associations with microplastics in the aquatic environment. These findings indicated that the characteristics and dynamics of fDOM in urban surface water are influenced by microplastics. Practitioner Points: Fluorescent dissolved organic matters were identified in urban surface waters.Expanded polystyrene (EPS) had shown two fluorophores at Em/Ex = 250/302 and Em/Ex = 260/333.Low‐density polyethylene (LDPE) had one fluorophore at Em/Ex = 260/333.Fluorophore and component intensity in the aquatic settings exhibited associations with microplastics. [ABSTRACT FROM AUTHOR]

Three polymeric materials; polystyrene (amorphous), low-density polyethylene (semi-crystalline), and poly(methyl methacrylate) (amorphous) were used to explore their behavior and properties during processing using a co-rotating twin-screw extruder. Injection molding and compression molding were used for preparing the test specimens. Screw speed and barrel set temperatures were considered as the main processing variables while observing the process energy consumption of the extruder. The tensile, thermal, and rheological properties of the extruded materials under different processing conditions were evaluated. Test results confirmed that the motor power of the extruder for processing polystyrene and low-density polyethylene increased with increasing screw speed and decreased with increasing barrel set temperatures. Motor power for processing poly(methyl methacrylate) increased significantly with increasing screw speed. The total power consumption of the barrel heaters for processing polystyrene and low-density polyethylene slightly increased with the barrel set temperatures. The tensile modulus of polystyrene decreased with increasing screw speed at higher barrel set temperatures, while low-density polyethylene showed no significant variation. The tensile modulus of poly(methyl methacrylate) did not exhibit a clear trend with the extruder process settings. The effect of process settings on the glass transition temperature and melting temperature of the polymers was not significant, and no evidence was found of any molecular degradation during processing. Rheological properties of poly(methyl methacrylate) showed a significant variation with increasing screw speed and barrel set temperatures, while those of polystyrene and low-density polyethylene did not exhibit a consistent variation. [ABSTRACT FROM AUTHOR]

In this study, hydrothermal co-liquefaction of restaurant waste for biocrude production was conducted. The feedstock was resembled using the organic fraction of restaurant waste and low-density polyethylene, polypropylene, polystyrene, and polyethylene terephthalate, four plastic types commonly present in municipal solid waste. Using design of experiment and a face-centered central composite design, three factors (feedstock plastic fraction, temperature, time) were varied at three levels each: feedstock plastic fraction (0, 0.25, 0.5), temperature (290 °C, 330 °C, 370 °C), and reaction time (0 min, 30 min, 60 min). The literature reports positive synergistic interactions in hydrothermal co-liquefaction of biomass and plastics; however, in this work, only negative synergistic interactions could be observed. A reason could be the high thermal stability of produced fatty acids that give little room for interactions with plastics. At the same time, mass might transfer to other product phases. [ABSTRACT FROM AUTHOR]

The production of hydrogen from plastic and biomass waste via processes powered by renewable electricity can be a pivotal contributor to an effective waste management system in a circular economy. Copyrolysis of plastic and biomass waste mixtures can be economically appealing, not only by eliminating the need for waste stream separation but also by potentially synergizing hydrogen production. In this study, we present evidence of such hydrogen production synergy in plasma copyrolysis of mixtures of low-density polyethylene (LDPE) and cellulose (CE) as plastic and biomass waste models, respectively. We treated samples made of mixtures of LDPE and CE powders at five different mass ratios, ranging from 100% LDPE to 100% CE. We used non-thermal nitrogen plasma and argon plasma in a Streamer Dielectric-Barrier Discharge (SDBD) configuration under atmospheric pressure conditions. Synergistic hydrogen production was observed when nitrogen was used as the working gas, but not with argon, resulting in up to 37% greater hydrogen production compared to non-synergistic expectations. This outcome is attributed to the nitrogen-doped oxygenated carbonaceous residues from CE pyrolysis catalyzing the dehydrogenation and reforming of light alkanes resulting from the decomposition of LDPE. [Display omitted] • Plasma copyrolysis of LDPE and cellulose using nitrogen leads to increased hydrogen yield. • Synergy leads to up to 37% increased hydrogen production. • The lowest energy cost of 1.5 MWh/kg-H 2 is achieved for 1:2 LDPE:cellulose mass ratio. • Synergy attributed to nitrogen doping of cellulose-derived carbonaceous residues. [ABSTRACT FROM AUTHOR]

The present study focuses on the effect of octylphenoxy poly(ethyleneoxy)ethanol (IGEPAL CA 630) on the environmental stress cracking resistance (ESCR) of blends of polypropylene (PP) and low-density polyethylene (LDPE) at different weight fractions without and with the addition of two compatibilizers, corresponding to styrene-ethylene-butylene-styrene (SEBS) copolymer and styrene-ethylene-butylene maleate (SEBS-g-MA). Compression molding was used after mixing the melt in a Brabender internal mixer to create the blends. ESCR of the blends was determined by exposing the blends to a solution of IGEPAL CA 630 the presence of stress. Mechanical (tensile) and thermal properties are extracted to evaluate the effect of adding the compatibilizers SEBS and SEBS-g-MA to the blend. In the environmental stress cracking (ESCR) tests, the time to failure increases with increasing PP content, despite PP's greater resistance to ESCR than LDPE. The addition of SEBS-g-MA to the blend significantly improves the flexibility and ESCR performance of PP/LDPE blends with specific weight fractions. [ABSTRACT FROM AUTHOR]

• Interaction of plastic and scrap tyre during co-pyrolysis is plastic-specific. • Mixing PP or LDPE with tyre can promote aliphatic hydrocarbon and suppress PAHs. • Mixing PS with tyre can suppress PAHs and enhance MAs production, especially BTEX. • 75 wt% LDPE or PS with tyre at 600 °C yields sulphur-free pyrolytic oil. • Tyre char can promote cracking reactions in LDPE thermal degradation. Fast co-pyrolysis offers a sustainable solution for upcycling polymer waste, including scrap tyre and plastics. Previous studies primarily focused on slow heating rates, neglecting synergistic mechanisms and sulphur transformation in co-pyrolysis with tyre. This research explored fast co-pyrolysis of scrap tyre with polypropylene (PP), low-density polyethylene (LDPE), and polystyrene (PS) to understand synergistic effects and sulphur transformation mechanisms. A pronounced synergy was observed between scrap tyre and plastics, with the nature of the synergy being plastic-type dependent. Remarkably, blending 75 wt% PS or LDPE with tyre effectively eliminated sulphur-bearing compounds in the liquid product. This reduction in sulphur content can substantially mitigate the release of hazardous materials into the environment, emphasizing the environmental significance of co-pyrolysis. The synergy between PP or LDPE and tyre amplified the production of lighter hydrocarbons, while PS's interaction led to the creation of monocyclic aromatics. These findings offer insights into the intricate chemistry of scrap tyre and plastic interactions and highlight the potential of co-pyrolysis in waste management. By converting potential pollutants into valuable products, this method can significantly reduce the release of hazardous materials into the environment. [ABSTRACT FROM AUTHOR]

Background: Plastics pollution and antimicrobial resistance (AMR) are two major environmental threats, but potential connections between plastic associated biofilms, the 'plastisphere', and dissemination of AMR genes are not well explored. Results: We conducted mesocosm experiments tracking microbial community changes on plastic surfaces transitioning from wastewater effluent to marine environments over 16 weeks. Commonly used plastics, polypropylene (PP), high density polyethylene (HDPE), low density polyethylene (LDPE) and polyethylene terephthalate (PET) incubated in wastewater effluent, river water, estuarine water, and in the seawater for 16 weeks, were analysed via 16S rRNA gene amplicon and shotgun metagenome sequencing. Within one week, plastic-colonizing communities shifted from wastewater effluent-associated microorganisms to marine taxa, some members of which (e.g. Oleibacter-Thalassolituus and Sphingomonas spp., on PET, Alcanivoracaceae on PET and PP, or Oleiphilaceae, on all polymers), were selectively enriched from levels undetectable in the starting communities. Remarkably, microbial biofilms were also susceptible to parasitism, with Saprospiraceae feeding on biofilms at late colonisation stages (from week 6 onwards), while Bdellovibrionaceae were prominently present on HDPE from week 2 and LDPE from day 1. Relative AMR gene abundance declined over time, and plastics did not become enriched for key AMR genes after wastewater exposure. Conclusion: Although some resistance genes occurred during the mesocosm transition on plastic substrata, those originated from the seawater organisms. Overall, plastic surfaces incubated in wastewater did not act as hotspots for AMR proliferation in simulated marine environments. [ABSTRACT FROM AUTHOR]

Transforming polyolefin waste into liquid alkanes through tandem cracking‐alkylation reactions catalyzed by Lewis‐acid chlorides offers an efficient route for single‐step plastic upcycling. Lewis acids in dichloromethane establish a polar environment that stabilizes carbenium ion intermediates and catalyzes hydride transfer, enabling breaking of polyethylene C−C bonds and forming C−C bonds in alkylation. Here, we show that efficient and selective deconstruction of low‐density polyethylene (LDPE) to liquid alkanes is achieved with anhydrous aluminum chloride (AlCl3) and gallium chloride (GaCl3). Already at 60 °C, complete LDPE conversion was achieved, while maintaining the selectivity for gasoline‐range liquid alkanes over 70 %. AlCl3 showed an exceptional conversion rate of 5000 gLDPEmolcat-1h-1 ${{{\rm g}}_{{\rm L}{\rm D}{\rm P}{\rm E}}{{\rm \ }{\rm m}{\rm o}{\rm l}}_{{\rm c}{\rm a}{\rm t}}^{-1}{{\rm \ }{\rm h}}^{-1}}$ , surpassing other Lewis acid catalysts by two orders of magnitude. Through kinetic and mechanistic studies, we show that the rates of LDPE conversion do not correlate directly with the intrinsic strength of the Lewis acids or steric constraints that may limit the polymer to access the Lewis acid sites. Instead, the rates for the tandem processes of cracking and alkylation are primarily governed by the rates of initiation of carbenium ions and the subsequent intermolecular hydride transfer. Both jointly control the relative rates of cracking and alkylation, thereby determining the overall conversion and selectivity. [ABSTRACT FROM AUTHOR]

Transforming polyolefin waste into liquid alkanes through tandem cracking‐alkylation reactions catalyzed by Lewis‐acid chlorides offers an efficient route for single‐step plastic upcycling. Lewis acids in dichloromethane establish a polar environment that stabilizes carbenium ion intermediates and catalyzes hydride transfer, enabling breaking of polyethylene C−C bonds and forming C−C bonds in alkylation. Here, we show that efficient and selective deconstruction of low‐density polyethylene (LDPE) to liquid alkanes is achieved with anhydrous aluminum chloride (AlCl3) and gallium chloride (GaCl3). Already at 60 °C, complete LDPE conversion was achieved, while maintaining the selectivity for gasoline‐range liquid alkanes over 70 %. AlCl3 showed an exceptional conversion rate of 5000 gLDPEmolcat-1h-1 ${{{\rm g}}_{{\rm L}{\rm D}{\rm P}{\rm E}}{{\rm \ }{\rm m}{\rm o}{\rm l}}_{{\rm c}{\rm a}{\rm t}}^{-1}{{\rm \ }{\rm h}}^{-1}}$ , surpassing other Lewis acid catalysts by two orders of magnitude. Through kinetic and mechanistic studies, we show that the rates of LDPE conversion do not correlate directly with the intrinsic strength of the Lewis acids or steric constraints that may limit the polymer to access the Lewis acid sites. Instead, the rates for the tandem processes of cracking and alkylation are primarily governed by the rates of initiation of carbenium ions and the subsequent intermolecular hydride transfer. Both jointly control the relative rates of cracking and alkylation, thereby determining the overall conversion and selectivity. [ABSTRACT FROM AUTHOR]

Nowadays, increased food safety and decreased food waste are two of the major global interests. Self-healable active packaging materials are an attractive option to achieve such targets. This property is critical for the hygiene and the consumption appropriateness of the food. Polylactic acid is a very promising polymeric matrix that potentially could replace the widely used low-density polyethylene due to its biobased origin and its easy biodegradable nature. The main drawback of this polymeric matrix is its brittle, fragile nature. On the other hand, tetraethyl citrate is a biobased approved food additive which became an attractive option as a plasticizer for industries seeking alternative materials to replace the traditional petrochemically derived compounds. A novel biobased film exhibiting self-healing behavior suitable for food-active packaging was developed during this study. Polylactic acid's brittleness was reduced drastically by incorporating tetraethyl citrate, and a random cut on the original self-repairing film was fully healed after 120 s. The optimum concentration of tetraethyl citrate in the polylactic acid was around 15% v/w with a water/oxygen barrier close to the relevant of polylactic acid and low migration. According to the EC50 parameter, the antioxidant activity was 300% higher than the relevant of pure polylactic acid, while according to the thiobarbituric acid and heme iron parameters, the film resisted lipid oxidation and deterioration. Finally, the total viable count parameter indicates the strong antimicrobial activity of this sample. [ABSTRACT FROM AUTHOR]

In this work, a simplified comprehensive three-dimensional numerical model is developed to study the effect of hydrogen production on co-gasification of biomass and low-density polyethylene (LDPE). CFD software AVL Fire 2020 inbuilt algorithms were employed to develop the gas phase while the solid phase was developed by user-defined FORTRAN subroutines. Solid hydrodynamics, fuel conversion, homogenous and non-homogenous chemical reactions, and heat transfer, including radiation, subroutines were defined and incorporated into AVL FIRE explicitly. Species concentrations of the syngas were analyzed for co-gasification of Beechwood and LDPE for three distinct types of bed materials (silica sand, Na-Y zeolite, and ZSM-5 zeolite). Then, the model is validated with experiment results available in the literature for a lab-scale fluidized bed reactor. The highest hydrogen production was observed in Na-Y zeolite followed by ZSM-5 zeolite and silica in both numerical and experimental analysis for the co-gasification of Beechwood and LDPE, providing a reasonable agreement between the numerical and the experimental results. Therefore, the current model predicts the enhancement of the quality of hydrogen-rich syngas through the application of co-pyrolysis within a fluidized bed reactor, incorporating a catalytic bed material. [ABSTRACT FROM AUTHOR]

Plastic accumulation is a severe threat to the environment due to its resistivity to thermal, mechanical and biological processes. In recent years, microbial degradation of plastic waste disposal is of interest because of its eco-friendly nature. In this study, a total of 33 fungi were isolated from the plastisphere and out of which 28 fungal species showed halo zone of clearance in agarized LDPE media. The fungus showing highest zone of clearance was further used to evaluate its degradation potential. Based on morphological and molecular technique, the fungus was identified as Cladosporium sphaerospermum. The biodegradation of LDPE by C. sphaerospermum was evaluated by various methods. The exposure of LDPE with C. sphaerospermum resulted in weight loss (15.23%) in seven days, higher reduction rate (0.0224/day) and lower half-life (30.93 days). FTIR analysis showed changes in functional group and increased carbonyl index in LDPE treated with C. sphaerospermum. SEMimages evidenced the formation of pits, surface aberrations and grooves on the LDPE film treated with the fungus whereas the untreated control LDPE film showed no change. AFM analysis confirmed the surface changes and roughness in fungus treated LDPE film. This might be due to the extracellular lignolytic enzymes secreted by C. sphaerospermum grown on LDPE. The degradation of polyethylene by Short chain alkanes such as dodecane, hexasiloxane and silane were identified in the extract of fungus incubated with LDPE film through GC–MS analysis which might be due to the degradation of LDPE film by C. sphaerospermum. This was the first report on the LDPE degradation by C. sphaerospermum in very short duration which enables green scavenging of plastic wastes. [ABSTRACT FROM AUTHOR]

Due to the miniaturization, integration and multi‐functional development of contemporary electronic devices, there is a growing need for efficient thermal conductive composite materials. This study focuses on enhancing the dispersion of modified boron nitride (mBN) within a linear low‐density polyethylene (LLDPE) phase by incorporating LLDPE‐graft‐Aminomethylpyridine (LLDPE‐g‐Py) to non‐covalently modify BN. Additionally, polymethyl methacrylate (PMMA) and LLDPE polymers were introduced to create modified BN/LLDPE/PMMA (mBN/LLDPE/PMMA) composites with a double percolation structure. The co‐continuous structure of the polymer composites was observed by using scanning electron microscopy (SEM). By selectively locating the BN modified by LLDPE‐g‐Py within the LLDPE phase, the co‐continuous structure of the LLDPE/PMMA blend was upgraded to a double percolation structure. This double percolation structure establishes a dense and optimal heat transfer network within the polymer matrix. The thermal conductivity of the mBN/LLDPE/PMMA composite with BN loading of 40 wt% was significantly increased to 1.12 Wm−1 K−1, which was 350% higher than that of pure LLDPE, 38% higher than that of the BN/LLDPE composite, and 17% higher than that of the BN/LLDPE/PMMA composite. This study offers valuable insights into non‐covalent modification techniques for BN and the design of double percolation structures in thermal conductive polymer composites. Highlights: The double percolation structure was successfully constructed by simple melt blending method with LLDPE and PMMA as matrix and BN as thermal conductive filler. The double percolation structure can significantly promote the efficiency of heat transfer inside the thermal conductive composites.A novel non‐covalent modifier LLDPE‐g‐Py was prepared to modify the surface of BN, and the selective localization of modified BN (mBN) in the LLDPE phase was realized. [ABSTRACT FROM AUTHOR]

In recent years, the presence and migration of PAEs in packaging materials and consumer products has become a serious concern. Based on this concern, the aim of our study is to determine the possible migration potential and speed of PAEs in benthic fish stored in vacuum packaging, as well as to monitor the storage time and type as well as polyethylene (PE) polymer detection.As a result of the analysis performed by µ-Raman spectroscopy, 1 microplastic (MP) of 6 µm in size was determined on the 30th day of storage in whiting fish muscle and the polymer type was found to be Polyethylene (PE) (low density polyethylene: LDPE). Depending on the storage time of the packaging used in the vacuum packaging process, it has been determined that its chemical composition is affected by temperature and different types of polymers are formed. 10 types of PAEs were identified in the packaging material and stored flesh fish: DIBP, DBP, DPENP, DHEXP, BBP, DEHP, DCHP, DNOP, DINP and DDP. While the most dominant PAEs in the packaging material were determined as DEHP, the most dominant PAEs in fish meat were recorded as BBP and the lowest as DMP. The findings provide a motivating model for monitoring the presence and migration of PAEs in foods, while filling an important gap in maintaining a safe food chain. [ABSTRACT FROM AUTHOR]

It is of great significance to understand the diffusion rate of the volatile corrosion inhibitor (VCI) in the VCI films for corrosion inhibition. The diffusion behavior of 1,2,3-Benzotriazole (BTA) in pure low density polyethylene (LDPE) and VCIs/LDPE blends was investigated using molecular dynamics (MD) simulation at 310, 328 and 353 K temperatures. The temperature dependence and diffusion property of BTA in LDPE were revealed. Subsequently, the accuracy of the MD simulations was confirmed by comparing the diffusion coefficients obtained from the MD simulations with those obtained from the experiments. The fractional free volume, interaction energy between BTA and VCIs/LDPE, activation energy of BTA and the self-diffusion behavior of LDPE on the diffusion of BTA were explored, which illustrated the microscopic diffusion mechanism of BTA in LDPE. Results showed that the diffusion coefficients of BTA increased with increasing temperature, increasing free volume and the more flexible chain of LDPE, while the increase in the interaction energy between BTA and VCIs/LDPE slowed down the diffusion of BTA. It can be concluded that the increase in the interaction energy between BTA and the system, the activation energy of BTA and the formation of H-bonds due to the addition of other VCIs led to the decrease in the diffusion coefficients of BTA. The strong molecular interactions between BTA and VCIs were the main reason for the decrease in the BTA diffusion coefficients. Adjusting the formulation of the VCI films can provide new ideas for regulating the BTA diffusion rate, which is beneficial for extending the corrosion inhibition time of BTA. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites have recently been introduced as lead-free shielding materials for use in medical and industrial applications. In this work, novel shielding materials were developed using low-density polyethylene (LDPE) mixed with four different filler materials. These four materials are cement, cement with iron oxide, cement with aluminum oxide, and cement with bismuth oxide. Different weight percentages were used including 5%, 15%, and 50% of the cement filler with LDPE. Furthermore, different weight percentages of different combinations of the filler materials were used including 2.5%, 7.5%, and 25% (i.e., cement and iron oxide, cement and aluminum oxide, cement and bismuth oxide) with LDPE. Bismuth oxide was a nanocomposite, and the remaining oxides were micro-composites. Characterization included structural properties, physical features, mechanical and thermal properties, and radiation shielding efficiency for the prepared composites. The results show that a clear improvement in the shielding efficiency was observed when the filler materials were added to the LDPE. The best result out of all these composites was obtained for the composites of bismuth oxide (25 wt.%) cement (25 wt.%) and LDPE (50 wt.%) which have the lowest measured mean free path (MFP) compared with pure LDPE. The comparison shows that the average MFP obtained from the experiments for all the eight energies used in this work was six times lower than the one for pure LDPE, reaching up to twelve times lower for 60 keV energy. The best result among all developed composites was observed for the ones with bismuth oxide at the highest weight percent 25%, which can block up to 78% of an X-ray. [ABSTRACT FROM AUTHOR]

In accordance with the Circular Economy Package of the European directive, the Spanish government compels manufacturers of plastic bags to include into their products a minimum of 70% of polyethylene (PE) waste. Following this mandate can be challenging and requires a deep knowledge of the alterations produced by the recycling in the main components of a plastic bag film: lineal low-density polyethylene (LLDPE), the LLDPE recycled post-industry, generated as waste from an industrial process (rLLDPE) and the PE recycled from post-consumer use (rPE), that has been picked up, cleaned, and reprocessed. This study provides insight in the macro and microstructural changes produced by several cycles of recycling in these materials. Specimens in the form of film for supermarket bags formed with these polymers have been subjected to several recycling sequences. The process closely mimics industrial processes. Four cycles have been applied to the samples. The evolution of mechanical properties, including tensile strength, elongation at break, and tear and impact tests, shows an obvious decrease due to degradation that is not an impediment for practical use after the four cycles of recycling according to the main specifications defined by the producer. Colorimetric measurements reveal no significant variations in the color of the films. The results of the FTIR and TGA analysis show degradation phenomena and changes in crystallinity in branching and the apparition of crosslinking that are in consonance with the mechanical data. There is also a difference between both types of recycled PE. In general, rLLDPE is more affected by the recycling than rPE. According to our findings, the limiting property would be the tearing. By comparing these values with bags available in the market, manufactured from 70–80% recycled material, we can infer that while two reprocessing cycles can lead to good results, a maximum of four cycles of recycling is advisable. [ABSTRACT FROM AUTHOR]

With concern growing regarding the impact of microplastics (MPs) on terrestrial ecosystems, it is important to assess the role invertebrates may play in the fate of MPs within these ecosystems. Commonly, MPs enter these environments through improperly discarded waste or the application of treated biosolids and/or wastewater on agricultural soils. The present study investigated whether three species of terrestrial isopod (Porcellio scaber, Porcellio laevis, and Porcellionides pruinosus) ingest plastic debris and generate MPs during exposures varying from 24 h to 14 days and whether this may have an adverse effect on their health. Test vessels were designed to expose isopods to plastic fragments in the form of polyethylene plastic foam. Isopods were exposed to plastic that was either (1) pristine, or (2) weathered in a soil and water solution prior to incorporation in test vessels. When exposed to weathered polyethylene, all three species generated MPs (minimum–maximum size values for all durations inclusive: P. laevis = 114–1673 µm, P. scaber = 99–1635 µm, P. pruinosus = 85–1113 µm) through the consumption of macroplastic fragments with no observed impact on their health. In the shorter‐duration exposures, the number of MPs generated by the isopod species in the present study was highly variable between experimental vessels (minimum–maximum generated MPs for 14‐day exposure: P. laevis = 25–420, P. scaber = 50–583, P. pruinosus = 48–311). However, as the exposure durations increased, there was a clear trend of increasing MP generation, indicating that the isopods continued to consume the plastic fragments as long as the surface was weathered. A significant difference in the size of generated MPs was observed as well, with smaller isopod species generating smaller MP fragments on average. The results of the present study confirm that certain species of isopod can contribute to the generation of MPs, which constitutes an additional pathway of MP exposure to soil ecosystems. Environ Toxicol Chem 2024;43:784–792. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of storage conditions “relative humidity”, “temperature” and “light”, each one at two levels (high and low), on the weight and color of dried seedless barberry after 120 days' storage . The effect of conditions was statistically analyzed in a completely randomized design experiment based on factorial . After adjusting the moisture content barberry color were measured for both samples. The samples in weights of 100g in the bags made of low density polyethylene (LDPE), high density polyethylene (HDPE) and polypropylene cast (CPP) were packaged and coded. Then samples were placed in a given storage conditions. Based on the results, all the hue angle and a/b ratio have not changed in all the packaging samples of films in the condition of “high relative humidity, low temperature and darkness” and “high relative humidity, low temperature and brightness” after 120 days of storage . The lowest difference in weight was observed in both samples packaged in bags of LDPE and HDPE films, at the same conditions . Also, in all the packaging samples at the “high relative humidity × low temperature” state, the lowest hue angle, lowest chroma and highest a/b ratio were observed, whilst at the similar state, the lowest difference in weight in samples packaged in polypropylene cast film bags was observed. [ABSTRACT FROM AUTHOR]

The application of low-density polyethylene (LDPE) has been confined to packaging applications due to its inadequate mechanical and tribological characteristics. We propose enhancing LDPE by integrating hard carbon spheres (CSs) to improve its strength, frictional characteristics, and wear resistance. LDPE/CS composites were created by blending LDPE with varying CS amounts (0.5–8 wt.%). Analysis using scanning electron microscopy and Raman spectroscopy confirmed CS presence in the LDPE matrix, with X-ray diffraction showing no microstructural changes post-blending. Thermal characterization exhibited notable improvements in thermal stability (~4%) and crystallinity (~7%). Mechanical properties such as hardness and Young's modulus were improved by up to 4% and 24%, respectively. Tribological studies on different composite samples with varying surface roughness under various load and speed conditions revealed the critical role of surface roughness in reducing friction by decreasing real contact area and adhesive interactions between asperities. Increased load and speed amplified shear stress on asperities, possibly leading to deformation and failure. Notably, integrating CSs into LDPE, starting at 1 wt.%, effectively reduced friction and wear. The composite with the highest loading (8 wt.%) displayed the most significant tribological enhancement, achieving a remarkable 75% friction reduction and a substantial 78% wear reduction. [ABSTRACT FROM AUTHOR]

Low‐density polyethylene (LDPE) is one of the most important plastics, which is produced unfortunately under extreme conditions. In addition, it consists of robust aliphatic C─C bonds which are challenging to cleave for plastic recycling. A low‐pressure and ‐temperature (pethylene = 2 bara, T = 70 °C) macromonomer‐based synthesis of long chain branched polyethylene is reported. The introduction of recycle points permits the polymerization (grafting to) of the macromonomers to form the long chain branched polyethylene and its depolymerization (branch cleavage). Coordinative chain transfer polymerization employing ethylene and co‐monomers is used for the synthesis of the macromonomers, permitting a high flexibility of their precise structure and efficient synthesis. The long chain branched polyethylene material matches key properties of low‐density polyethylene. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) mulching films have an important function in crop cultivation; at the end of their life, however, their removal and disposal become both an economic and environmental problem. One possible alternative to low-density polyethylene (LDPE) mulch is provided by certified soil-biodegradable mulch films, such as those produced by Novamont and commercially available under the trade name MaterBi®. MaterBi is a biodegradable thermoplastic material made with starch and a biodegradable copolyester based on proprietary technology. In this study, we compared two biodegradable MaterBi®-based films (commercial and experimental films) with bare soil and a low-density polyethylene to evaluate their effect on yield and on a number of qualitative characteristics (organoleptic and nutraceutical composition) of eggplant fruits (cv Mirabelle F1) grown in two different regions in Southern Italy (Sicily and Campania). In our study, the use of biodegradable MaterBi® films improved not only yield and production parameters, such as the number and average weight of fruits, but also lipophilic and hydrophilic antioxidant activity and phenolic and ascorbic acid content. For many parameters, responses differed according to the cultivation environment and, in particular, the site's pedoclimatic conditions. Our results suggest that biodegradable MaterBi®-based mulching films are a potentially valid alternative to traditional LDPEs, providing the production and quality benefits reported above and promoting environmental sustainability, thanks to their positive biodegradable properties. [ABSTRACT FROM AUTHOR]

Linear low-density polyethylene (LLDPE) is a type of plastic with a high percentage of solid waste and is hardly degradable. The characteristics of LLDPE such as high toughness and low density have the potential to be an alternative aggregate substitute for applications in non-structural mortar composites. The purpose of this study was to determine the suitable formulation of LLDPE aggregate substitution against silica sand for the application of non-structural adhesive mortar composites. Vinyl acetate/ethylene (VAE) surfactant (1.2 wt%) was used to improve the interface between LLDPE and the cement matrix. Mechanical testing; XRD and FTIR characterization; density measurements; compression, adhesion, and thermogravimetric test; and morphological observation were carried out in this experiment. The results showed that LLDPE substitution decreased physical properties and accelerated thermal degradation. Cracks occurred on higher amount of LLDPE composition due to big difference in polarity. Suitable LLDPE substitution composition for adhesive mortar is up to 50%. [ABSTRACT FROM AUTHOR]

This study evaluated the mechanical properties and the chemical and thermal characteristics of low-density polyethylene (LDPE) nanocomposites reinforced with graphene oxide for manufacturing via 3D printing. LDPE nanocomposites with different graphene oxide (GO) loadings (0.5% and 1.5%) were processed by a single-screw extruder. To characterize the pre-injected material, Fourier transform infrared spectroscopy (FTIR) and thermal characterization with thermogravimetry (TGA) were used. The injected material was also characterized with mechanical impact and traction tests. The results showed that incorporating GO into the polymeric matrix added hydroxyl groups to the matrix structure, with a 39.13% increase in Young's modulus for LDPE-1.5%wtGO samples. Mechanical tests of 3D printed samples showed that, with an increase in the amount of GO in the polymer matrix, the composite loses ductility, enabling its use in 3D printing technologies and thus encouraging new studies on printed materials for various applications. [ABSTRACT FROM AUTHOR]

Heat seal and mechanical properties of 1‐octene grafted low density polyethylene films containing various concentrations of Dicumyl peroxide as the initiator and 1‐octene grafting agent is investigated through using experimental measurements. The results of differential scanning calorimeter (DSC) measurements revealed that the melting temperature shifts to higher values and the peak of the DSC curve becomes wider with the increase of 1‐octene concentrations. Thermogravimetric analysis (TGA) revealed a higher thermal stability up to 20 °C for 1‐octene grafted PE compared with neat LDPE alloy. The results of stress–strain measurements revealed that the 1‐octene grafted PE alloys has higher tensile strength in comparison with neat PE alloy and samples containing only DCP initiator. The results of heat seal analysis indicated that both DCP initiator and 1‐octene tended to offer a moderate increase peel strength of PE alloy. DMTA measurements for various grafted PE alloys show a higher damping factor in comparison with neat LDPE alloy. Rheological measurements indicated a higher storage modulus up to 25% and higher complex viscosity for grafted PE samples containing 1‐octene comonomer. [ABSTRACT FROM AUTHOR]

The aim of the study is to understand and achieve storage stable, compatible plastic-modified asphalt binders. In view of global plastic accumulation, the potentiality of polymeric waste plastics is evaluated as an asphalt binder modifier; providing an alternate recycling option. However, due to phase separation issues between asphalt and plastic, the usage of waste plastic is preferred through dry mixing in asphalt mixture. In this study, the compatibility of polyethylene-modified asphalt binder was assessed along with appropriate parameters that can explain the actual phase separation occurring during storage stability testing. Two types of plastics including low-density polyethylene (LDPE) and high-density polyethylene (HDPE) were blended with a PG 58-28 neat binder after assessing their melting behavior along with polystyrene (PS) and polyethylene terephthalate (PET). The impacts of polyethylene size (2.36–1.18 mm, 0.6–0.3 mm, less than 0.3 mm), blending time (30, 60, 120, 180 min), hot storage duration (0, 24, 48 h), and compatibilizers (styrene-butadiene-styrene, nanosilica, corn oil, polyphosphoric acid) on the storage stability were assessed. G*/Sinδ was used as an initial measure to assess the separation index (SI) value. The results concluded that polyethylene is observed to be inert to asphalt and phase separation persists irrespective of size and compatibilizer. Nanosilica at a dosage of 0.5% was able to partially compatibilize (SI value improved from 5.4 to 1.87) PE with asphalt. Also, in the need for better parameters to better understand the phase separation, percentage recovery, fluorescence microscopy, and black space analysis were identified as proper tests to detect phase separation. [ABSTRACT FROM AUTHOR]