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In this study, a composite membrane was prepared from recycled low-density polyethylene (R-LDPE), thus helping to lighten plastics' load on the environment, while the powder of alumina was used to enhance the membrane contact angle, its porosity, and its mechanical properties. The membrane preparation was made by means of the thermally induced phase separation method by using the butyl acetate as a solvent, hexane as a non-solvent, and the alumina as an additive. The membrane crystalline property was assessed via the Fourier-transform infrared spectroscopy. The membrane characteristics were then investigated in terms of thickness, contact angle, pore size, porosity, mechanical test, bubble point pressure, atomic force microscopy, and scanning electron microscopy analysis. The results revealed that the addition of alumina had an important role in improving membrane structure, properties and therefore its performance. The evaluation of the R-LDPE-alumina membrane showed that it has a good porosity, good hydrophobicity, and better mechanical properties. The obtained membranes were also applicated to the vacuum membrane distillation to test their performance. [ABSTRACT FROM AUTHOR]

Introduction: Once dispersed in water, plastic materials become promptly colonized by biofilm-forming microorganisms, commonly known as plastisphere. Methods: By combining DNA sequencing and Confocal Laser Scanning Microscopy (CLSM), we investigated the plastisphere colonization patterns following exposure to natural lake waters (up to 77 days) of either petrochemical or biodegradable plastic materials (low density polyethylene - LDPE, polyethylene terephthalate - PET, polylactic acid - PLA, and the starch-based MaterBi® - Mb) in comparison to planktonic community composition. Chemical composition, water wettability, and morphology of plastic surfaces were evaluated, through Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), and static contact angle analysis, to assess the possible effects of microbial colonization and biodegradation activity. Results and Discussion: The phylogenetic composition of plastisphere and planktonic communities was notably different. Pioneering microbial colonisers, likely selected from lake waters, were found associated with all plastic materials, along with a core of more than 30 abundant bacterial families associated with all polymers. The different plastic materials, either derived from petrochemical hydrocarbons (i.e., LDPE and PET) or biodegradable (PLA and Mb), were used by opportunistic aquatic microorganisms as adhesion surfaces rather than carbon sources. The Mb-associated microorganisms (i.e. mostly members of the family Burkholderiaceae) were likely able to degrade the starch residues on the polymer surfaces, although the Mb matrix maintained its original chemical structure and morphology. Overall, our findings provide insights into the complex interactions between aquatic microorganisms and plastic materials found in lake waters, highlighting the importance of understanding the plastisphere dynamics to better manage the fate of plastic debris in the environment. [ABSTRACT FROM AUTHOR]

The potential of ecofriendly biochar, a carbon-rich byproduct of biomass pyrolysis, as a low-cost solid lubricating filler for low-density polyethylene (LDPE) sustainable biocomposites is investigated in this work. Tensile strength, hardness, thermogravimetric analysis (TGA), melting flow index (MFI), tensile test, flexural test, and frictional tests were used to characterize the biocomposites' mechanical, thermal, and tribological properties. Energy-dispersive X-ray spectroscopy (EDS) was used to assess the chemical composition of the biochar, while field-emission scanning electron microscopy (FESEM) was used to capture the biochar morphology. The results showed that the incorporation of biochar in LDPE matrix increased the mechanical characteristics of the biocomposites and resulted in a significant increase in tensile strength, flexural strength, and hardness. More specifically, the LDPE+10 wt% composite outperformed the pure LDPE matrix by 1.9% in tensile strength and 47% in flexural strength. Furthermore, integrating biochar into LDPE composites enhances thermal stability, lowers the melt flow index (MFI), and boosts the hardness by 24.3% for the composite with 10% biochar content. Furthermore, biochar improves wear resistance and durability, with the LDPE10 composite exhibiting a friction coefficient that is 56.3% lower than pure LDPE. These findings indicate that biochar is a viable, cost-effective, and environmentally friendly filler for improving the performance of LDPE-based biocomposites for many varieties of applications. [ABSTRACT FROM AUTHOR]

There has been growing interest in the use of polyethylene (PE) in the asphalt industry as one way to mitigate the adverse environmental impact of waste plastics. The main goal of this study was to evaluate the potential use of low-density polyethylene (LDPE) as a modifier for use in asphalt mixtures. In addition, this study also explored the potential synergistic impact of using elastomeric polymers typically used with asphalt binders as a co-modifier along with LDPE. This study was based on a comprehensive evaluation of the rheological and performance-related properties of asphalt binder from two very different sources as well as asphalt mixtures produced using a subset of these binders. Typical methods that are standard practice in the industry and methods that are being developed to evaluate the performance metrics of asphalt binders and mixtures were used. The two chemically diverse base binders and redundancy in the evaluation process were introduced to ensure a more robust evaluation of the expected properties. Overall, results demonstrate that although the impact of LDPE on the expected performance of the binder may vary with the source of binder, LDPE can be successfully used to enhance the properties of the asphalt binder in most respects, particularly with the synergistic use of a conventional elastomeric modifier. [ABSTRACT FROM AUTHOR]

Radiation protection is crucial in the protection of humans from the harmful effects of ionizing radiation. One of the most reliable ways of reducing the risk of occupationally exposed workers and the public in dental radiology is the installation of an effective radiation shielding barrier at the facility. Concrete barriers are predominantly used for dental shielding, however there is need to consider the use of lighter, ready‐made, and lower half value layer (HVL) materials as shielding materials in dental radiology facilities. In this work, low‐density polyethylene‐molybdenum oxide polymer composites were prepared (85C2H4‐15MoO3, 90C2H4‐10MoO3, and 95C2H4‐5MoO3), and the radiation attenuation measurements were carried out experimentally. The composites displayed acceptable x‐ray absorbing capabilities. 85C2H4‐15MoO3 polymer composite (DT1) showed optimal shielding in comparison with concrete. DT1 has an approximate HVL like concrete while it is 54.3% lighter than concrete. 85C2H4‐15MoO3 polymer composite is 1.5%, 0.8%, and 6.3% higher in linear attenuation coefficient than concrete at 60, 70, and 80 kVps, respectively. This implies that DT1 can effectively replace concrete at dental diagnostic energies. [ABSTRACT FROM AUTHOR]

The in-series connections of multi-pipes involving steel and polymeric materials were identified as being an effective design tool to extenuate water-hammer surges induced into an existing steel-main pipe-based hydraulic system. Although this design measure significantly reduced the magnitude of pressure-wave surges, it was limited by the expansion of the period of pressure-wave oscillations. This study addressed a holistical exploration and comparison of the effectiveness of the in-series connections of multi-pipes design measure used to control water-hammer surges into an existing steel water distribution piping systems. The extended one-dimensional water-hammer model, including the Vitkovsky and Kelvin-Voigt formulations, was developed to describe the transient flow, together with the Method of Characteristics implemented for numerical computations. The comparison of the numerical solution with observed data, quoted in the literature, and the alternative numerical solution demonstrated the accuracy of the developed solver. The test case appraised the capability of a variety of in-series setups of steel and plastic main-pipes for a reservoir-pipe-valve – based hydraulic system. The high- and low-density polyethylene (HDPE and LDPE) plastic material types were considered in this investigation. Results showed that the hydraulic system setup built upon an (LDPE-steel-LDPE) provided a satisfactory tradeoff between the dampening of pressure-wave magnitude and the expansion of the period of pressure-wave oscillations [ABSTRACT FROM AUTHOR]

This document describes a collection of patents related to elastomers and plastics. The patents cover a wide range of topics, including methods for enhancing bonding of thermoplastic composites, rubber compositions with carbon nanotubes, and manufacturing methods for low-density polyethylene. The document provides summaries of each patent, including information about the inventors and abstracts of the patents. [Extracted from the article]

Catalytic pyrolysis of waste HDPE and LDPE polyethylene was successfully carried out using a silica-alumina catalyst at 450 °C under N2 atmosphere. The synthesized silica-alumina is mesoporous and shows type IV isotherm. Thermal pyrolysis (without any catalyst) provided 47% waxlike hydrocarbons at 485 °C. On the other hand, more than 80% liquid yield was achieved using silica-alumina catalysts from waste HDPE and LDPE. The highest liquid yield was obtained from LDPE (87.69%) than HDPE (83.25%) at a catalyst-to-plastic ratio of 1:25. The 1H NMR shows that the liquid product does not contain any aromatic compound. The GCMS, 1H NMR, and FTIR confirmed that the liquid contains linear and branched alkanes and alkenes. [ABSTRACT FROM AUTHOR]

Plastics have quickly become one of the major pollutants in aquatic environments worldwide and solving the plastic pollution crisis is considered a central goal of modern society. In this study, 10 different plastic samples, including high‐ and low‐density polyethylene and polypropylene, were collected from a deeply polluted urban estuary in Brazil. By employing different isolation and analysis approaches to investigate plastic‐associated bacteria, a predominance of potentially pathogenic bacteria such as Acinetobacter, Aeromonas, and Vibrio was observed throughout all plastic samples. Bacteria typically found in the aquatic environment harboured clinically relevant genes encoding resistance to carbapenems (blaKPC) and colistin (such as mcr‐3 and mcr‐4), along with genetic determinants associated with potentially active gene mobilization. Whole genome sequencing and annotation of three plastic‐associated Vibrio strains further demonstrated the carriage of mobile genetic elements and antimicrobial resistance and virulence genes. On the other hand, bacteria isolated from the same samples were also able to produce esterases, lipases, and bioemulsifiers, thus highlighting that the plastisphere could also be of special interest from a biotechnological perspective. [ABSTRACT FROM AUTHOR]

Marine plastic pollution is a major concern worldwide, but the understanding of plastisphere dynamics remains limited in the southern hemisphere. To address this knowledge gap, we conducted a study in South Australia to investigate the prokaryotic community of the plastisphere and its temporal changes over 4 weeks. We submerged six plastic types (i.e., High‐Density Polyethylene [HDPE], Polyvinyl chloride [PVC], Low‐Density Polyethylene [LDPE], Polypropylene [PP], Polystyrene [PS] and the understudied textile, polyester [PET]) and wood in seawater and sampled them weekly to characterize the prokaryotic community using 16S rRNA gene metabarcoding. Our results showed that the plastisphere composition shifted significantly over short time scales (i.e., 4 weeks), and each plastic type had distinct groups of unique genera. In particular, the PVC plastisphere was dominated by Cellvibrionaceae taxa, distinguishing it from other plastics. Additionally, the textile polyester, which is rarely studied in plastisphere research, supported the growth of a unique group of 25 prokaryotic genera (which included the potential pathogenic Legionella genus). Overall, this study provides valuable insights into the colonization dynamics of the plastisphere over short time scales and contributes to narrowing the research gap on the southern hemisphere plastisphere. [ABSTRACT FROM AUTHOR]

It is proverbial that the rheological properties of low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) are disparate because of their different molecular microstructures due to the unlike methods of polymerization. In this work, multiple characterizations including Size-Exclusion Chromatography (SEC) coupled with low-angle light scattering and viscosmeter, 13C Nuclear Magnetic Resonance, Crystallization Elution Fractionation (CEF) and Differential Scanning Calorimetry (DSC) were conducted to get detailed information of branching on different LDPEs and LLDPEs. It was found that, in our case, LDPEs possessed higher molecular weight and greater amounts of long-chain branching (LCB) in comparison with LLDPEs. The Chemical Composition Distribution (CCD) of each LLDPE sample depends strongly on the catalyst used. LLDPE produced by Z-N catalyst exhibited broad short-chain branching (SCB) distribution (less uniform composition distribution), whereas LLDPE obtained by metallocene catalyst showed more uniform microstructure. Unlikely, the two LDPEs displayed wider but unimodal distribution corresponding to the free-radical polymerization mechanism. Both linear and nonlinear rheological results were strongly influenced by the presence of LCB. LDPEs in this work exhibited higher zero shear-viscosity, higher values of storage modulus, longer relaxation times, and higher activation energy comparing to LLDPEs. The presence of LCB leads to more pronounced strain hardening behavior in the elongational flow which is neglected in LLDPE. The molecular structures of linear and branched PEs were consistent with the rheological properties. [ABSTRACT FROM AUTHOR]

The current study proposes an efficient coating methodology for the development of low-density polyethylene (LDPE) films with prolonged bioactivity for food packaging applications. Three natural phenolic-based substances were incorporated at optimized concentrations in methyl-cellulose-based solutions and used as coatings on LDPE films. The amount of surfactant/emulsifier was optimized to control the entrapment of the bioactive substances, minimizing the loss of the substances during processing, and offering prolonged bioactivity. As a result, the growth of Escherichia coli was substantially inhibited after interaction with the coated films, while coated films presented excellent antioxidant activities and maintained their mechanical performance after coating. Considerable bioactivity was observed after up to 7 days of storage in sealed bags in the case of carvacrol- and thymol-coated films. Interestingly, films coated with olive-leaf extract maintained a high level of antimicrobial and antioxidant properties, at least for 40 days of storage. [ABSTRACT FROM AUTHOR]

Injection-molded polyethylene plates exhibit highly anisotropic mechanical behavior due to, e.g., the uneven orientation of the polymer chains during the molding process and the differential cooling, especially in the thickness direction. Elastoplastic finite element modeling of these plates in particular is used with isotropic yield criteria like von Mises, trading off accuracy in favor of simpler constitutive characterization and faster solution. This article studies three different anisotropic yield criteria, namely, Hill 1948, Barlat Yld91, and Barlat Yld2004-18P, for the finite element modeling of low-density polyethylene (LDPE) at large uniaxial tensile deformation and compares the accuracy and computation time with von Mises. A simplified calibration technique is investigated to identify the constitutive parameters of the studied Barlat group yield criteria. The calibration process is simplified in the sense that only uniaxial tensile tests with digital image correlation measurements are used for the calibration of all the yield criteria studied in this article, although a standard calibration procedure for the Barlat group yield criteria requires additional material testing using more demanding test setups. It is concluded that both Barlat Yld91 and Barlat Yld2004-18P yield criteria can be calibrated with only a few tensile tests and still capture anisotropy in deformation–stress–strain at different levels of accuracy. [ABSTRACT FROM AUTHOR]

The crystallinity of Linear Low‐Density Polyethylene (LLDPE) is influenced significantly by short‐chain branches (SCBs) present in the backbone of the polymer. Despite the importance of this aspect, with only a few linear comonomers being currently used in the commercial production of LLDPE. It is found that by introducing branched comonomers, the melting point and crystallinity of LLDPE can be influenced to a greater extent than with linear comonomers. Since only a few linear comonomers are currently used in the production of LLDPE, the characterization of LLDPEs with branched comonomer has been often overlooked. By combining High‐Temperature‐Size‐Exclusion Chromatography (HT‐SEC), Nuclear Magnetic Resonance (NMR) spectroscopy, and Infrared (IR) spectroscopy, it is shown that standard HT‐SEC analysis using an IR detector is also applicable to polymers containing branched comonomers. [ABSTRACT FROM AUTHOR]

This study aimed to characterize edible films based on potato starch and fermented and non-fermented whey solutions by Lactobacillus rhamnosus and Lactobacillus acidophilus and applied the formulated edible films to cover Manchego-type cheese to evaluate their quality characteristics during the storage using two different secondary packages. The results indicated that among quality characteristics evaluated, thickness (0.15–0.25 mm) and tensile strength (0.19–0.30 MPa) were significantly higher (compared to control edible films) in edible films formulated with fermented whey, regardless of the lactic acid bacteria (LAB) used. After 14 days of storage, the moisture content, weight loss, and color characteristics of cheese were maintained by both edible films and linear low-density polyethylene (LLDPE) bags. The application of edible films with fermented whey increases (4.21–5.98 log CFU/g) the content of beneficial microorganisms in the cheese, which are maintained during the storage (> 7 log cycles) regardless of the conditions. Consumer judges did not notice the application of edible films based on fermented whey to the cheese at the beginning and after 14 days of storage (LLDPE packaging), showing scores between I like and I like much in all samples evaluated. This study demonstrated that the fermentation process of whey solution for film forming and the employment of LLDPE as secondary packaging maintain the quality characteristics of Manchego-type cheese during storage. [ABSTRACT FROM AUTHOR]

Packing supplies and storage requirements significantly influence the value and stability of phenolic compounds in stored-dried garlic. This experiment aimed to evaluate and assess the performance of packing materials at various temperatures and storage times. Concentrations of allicin and primary phenolic acids packed in dried garlic low-density polyethylene/nylon/low-density polyethylene (LDPE/Nylon/LDPE) and low-density polyethylene/aluminium foil/low-density polyethylene (LDPE/AL/LDPE) pouches and kept at 10, 30 and 50 °C for 120 days were monitored by ultra-high-performance liquid chromatography (UPLC) techniques. The percentage of allicin retention ranged between 1.72 to 17.24% and 1.72 to 9.48% was observed in stored-dried garlic packed in LDPE/Nylon/LDPE and LDPE/AL/LDPE pouches, respectively. The first-order reaction found the kinetic of non-enzymatic browning in dried garlic packed in different packaging materials during storage. The Arrhenius calculation might be employed to characterize the temperature dependency of reaction kinetics. The activation energies for non-enzymatic browning were 1.67 and 14.04 kJ/mol for dried garlic packed in LDPE/Nylon/LPDE and LDPE/AL/LPDE pouches, respectively. The combination of LDPE/AL/LDPE pouch and storage temperature of 30 °C provided promising packaging materials and storage conditions to preserve the quality and stability of bioactive compounds in dried garlic. [ABSTRACT FROM AUTHOR]

Safety concerns pertaining to PAHs occurrence in agri-food commodities have been a source of great concern. Concerns have been expressed about offering additional insights on screening agri-food commodities to benefit consumers, as evidence-based study knowledge on the health risks posed by ingestion of PAHs-contaminated food by people has increased. According to research, the majority of edible oil-yielding seeds are contaminated with PAHs. These toxins of PAHs can enter the human food chain through the consumption of edible oils. At present, the control of PAHs is mainly through the optimization of the production process, and the specificity is not strong. PAHs' contamination levels varied in different edible oils depending on the type of oil, production process and oilseeds' storage conditions. In this overview, we have decisively assessed the existing data on PAH incidence, main sources, and decontamination in assorted edible oils. This review seeks to provide a comprehensive overview of existing and emerging methods/technologies for PAH determination and elimination, in order to bridge information gaps toward ensuring a green and sustainable remedial approach for PAH-contaminated in edible plant-based oils. This work summarizes the very recently published works of the last years. Abbreviations: PAHs, Polycyclic aromatic hydrocarbons; HPAHs, high Polycyclic aromatic hydrocarbons; LPAHs, low Polycyclic aromatic hydrocarbons; Nap, naphthalene; Acy, acenaphthylene; Ace, acenaphthene; Flu, fluorine; Phe, phenanthrene; Ant, anthracene; Flt, fluoranthene; Pyr, pyrene; BaA, benz[a]anthracene; Chr, chrysene; BbF, benzo[b]fluoranthene; BkF, benzo[k]flouranthene; BaP, benzo[a]pyrene; DahA, dibenz[a,h]anthracene; BghiP, benzo[g,h,i] perylene; IcdP, indeno[1,2,3-cd]pyrene; 5MC, 5-methylchrysene; BjF, benzo[j]fluoranthene; DBaiP, dibenzo[a,i]pyrene; DalP, dibenzo[a,l]pyrene; DaeP, dibenzo[a,e]pyrene; DahP, dibenzo[a,h]pyrene; GC, gas chromatography; FLD, fluorescence detector; MS, mass spectrometry; SPE, solid-phase extraction; HACA, hydrogen abstraction acetylene addition; SPMD, short path molecular distillation; TP, tocopherol; TBHQ, tert-butyl hydroquinone; PET, polyethylene, HDPE, high-density polyethylene; LDPE, low-density polyethylene. [ABSTRACT FROM AUTHOR]

Adhesion and moisture damage are significant factors in the early failure of pavements. This study examined the adhesion and moisture resistance of three types of binders (40–50, 60–70, and 80–100 pen bitumen) modified with paraffin wax (PW), hydrated lime (HL), and low-density polyethylene (LDPE) at dosages of 1% and 2% by weight of the binder. The Bitumen Bond Strength (BBS) test was performed using the Pneumatic Adhesion Tensile Testing Instrument (PATTI) to measure Pull-Off Tensile Strength (POTS) and determine the type of failure following dry and wet conditioning. Additionally, the mixture was tested for moisture susceptibility using the Rolling Bottle Test (RBT). The RBT results showed that adding LDPE and HL to the control binder increased bitumen coverage, indicating greater resistance to moisture damage. In contrast, adding PW reduced bitumen coverage, indicating higher susceptibility to moisture damage. Based on the BBS test, LDPE and HL-modified bitumen developed greater bond strengths as POTS values increased, while PW-modified bitumen developed decreased bond strengths as POTS values decreased. [ABSTRACT FROM AUTHOR]

Three different compatibilizers were used; namely: Fusabond (FSB) which is a maleic anhydride grafted polyethylene, montanic acid (E wax), and used engine oil (UEO) were incorporated into cellulose acetate/low density polyethylene (CA/LDPE) composites at three fiber contents: 5, 15 and 30 phr. Three series of samples consisting of treated composites using coupling agents were prepared, while one group was left untreated as a reference composite. To assess the performance of the composites, different testing techniques were used. These include attenuated total reflectance spectroscopy(FTIR-ATR), thermogravimetric analysis(TGA), differential scanning calorimetry(DSC), tensile test, dynamic mechanical thermal analysis(DMTA), and scanning electron microscopy(SEM). The presence of ethylene vinyl acetate (EVA) in LDPE enhanced the adhesion at the polymer/fiber interface, as reflected by the increase of Young's modulus by 75, 166, and 245% respectively compared to neat LDPE, an increase of the storage modulus and a reduction of the damping factor value. Incorporating Fusabond was also found to affect slightly the mechanical properties with high fiber contents compared to the composites without the coupling agent by 13%. On the other hand, the use of montanic acid and used engine oil affected the cellulose acetate fibers distribution within the matrix. The UEO enhanced the dispersion but acted as a plasticizer resulting in a slight reduction of the crystallinity. Moreover, the interaction between the LDPE matrix and the CA fibres was indicated by the resulting fracture surface morphology. The results obtained suggest that the CA/LDPE composites would be suitable for packaging or used in automotive applications. [ABSTRACT FROM AUTHOR]

The resiliency of plastic products against microbial degradation in natural environment often creates devastating changes for humans, plants, and animals on the earth's surface. Biodegradation of plastics using indigenous bacteria may serve as a critical approach to overcome this resulting environmental stress. In the present work, a polyethylene degrading bacterium Alcaligenesfaecalis strain ISJ128 (Accession No. MK968769) was isolated from partially degraded polyethylene film buried in the soil at plastic waste disposal site. The biodegradation studies were conducted by employing various methods such as hydrophobicity assessment of the strain ISJ128, measurement of viability and total protein content of bacterial biofilm attached to the polyethylene surface. The proliferation of bacterial cells on polyethylene film, as indicated by high growth response in terms of protein content (85.50 µg mL−1) and viability (1010 CFU mL−1), proposed reasonable suitability of our strain A.faecalis ISJ128 toward polyethylene degradation. The results of biodegradation assay revealed significant degradation (10.40%) of polyethylene film within a short period of time (i.e., 60 days), whereas no signs of degradation were seen in control PE film. A.faecalis strain ISJ128 also demonstrated a removal rate of 0.0018 day−1 along with half-life of 462 days. The scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectroscopy studies not only displayed changes on polyethylene surface but also altered level of intensity of functional groups and an increase in the carbonyl indexes justifying the degradation of polyethylene film due to bacterial activity. In addition, the secondary structure prediction (M fold software) of 16SrDNA proved the stable nature of the bacterial strain, thereby reflecting the profound scope of A.faecalis strain ISJ128 as a potential degrader for the eco-friendly disposal of polyethylene waste. Schematic representation of methodology [ABSTRACT FROM AUTHOR]

Large amounts of PET bottles are used worldwide as primary packaging for numerous liquids, including water and soft drinks. In many cases, between two and eight of such bottles are bundled for transport and sales using plastic collation shrink film. This study evaluates paper-based alternatives for plastic bundling material using a life cycle assessment (LCA) of four different types of bundle packaging: LDPE shrink film, recycled Low-Density Polyethylene (rLDPE) shrink film, Ecogrip (existing paper-based bundle packaging) and Ecobundle (new paper-based bundle packaging). The study focuses on the case of bundling six bottles of 1.5 L of sparkling water. The most environmentally friendly option is identified, taking into consideration the material usage, effects on human health and effects on the biosphere. It is concluded that the new corrugated board-based bundling method (Ecobundle) is very promising. Further optimization of the design, minimization of material, improved choice of materials and improved design of the production machinery may result in a corrugated board performing even better than rLDPE shrink film in terms of the global warming potential. [ABSTRACT FROM AUTHOR]

Linear low‐density polyethylene (LLDPE) combined with the piperazine pyrophosphate (PAPP) and melamine cyanurate (MCA) was adopted to prepare the flame retardant LLDPE composite by melt blending. The research results showed that the PAPP/MCA mixture with a mass ratio of 4:1 presented the optimal flame retardant effect. With the 25 wt% addition amount, the LLDPE composite passed the UL‐94 V‐0 level (1.6 mm), and the limiting oxygen index (LOI) reached 29.4%. The peak of heat release rate (PHRR) decreased by 78.9% from 877.5 to 185.0 kW/m2, which is attributed to the good synergistic effect between PAPP and MCA, forming the stable and compact char layer. Besides, the thermal behaviors were characterized through thermogravimetric (TG) analysis, and the synergistic mechanism was investigated by scanning electron microscopy (SEM), TG analysis‐infrared spectrometry (TG‐IR), and x‐ray photoelectron spectroscopy (XPS). The results indicate that the good synergistic flame retardant effect can enhance the flame retardancy of LLDPE materials, and with the addition of MCA and PAPP, a flame retardant LLDPE composite with good thermal stability and mechanical properties can be prepared with no molten droplets on combustion, which provides a feasible solution for the application of high‐performance halogen‐free flame retardant LLDPE materials. [ABSTRACT FROM AUTHOR]

The topic of environmental contamination is currently regarded as one of the most urgent and significant challenges in contemporary society. Several strategies must be implemented to mitigate the environmental impact caused by waste materials, such as to rice husks ash, plastic, and other materials. Low-density polyethylene is widely recognized in academic circles for its distinctive property of having a low melting point and demonstrating inferior thermal stability. However, the utilization of RHA has promise for augmenting the thermal LDPE. The inclusion of silica inside rice husk ash functions as a flame retardant, hence augmenting the material's capacity to resist combustion and thermal degradation. The objective of this study is to utilization of eco-friendly RHA waste as reinforcement in LDPE thermoplastics. RHA is produced by the coprecipitation process. Rheomixer is used to make thermoplastic composites by incorporate RHA into LDPE 0, 2, 4, 6, 8, and 10 wt.%. The micrograph of the failure surface of the composite material consisting of LDPE filled with reactive hot-melt adhesive RHA particles reveals significant variations in particle sizes. In adittion XRD graph showed a decrease in intensity when 6% wt and 8% wt RHA were added. The results of thermal analysis with DSC showed an increase in the melting point of the sample with RHA reinforcement from 108.96-109.21oC and 482.47-500.09oC. The incorporation of RHA as a reinforcement in LDPE holds promise for its utilization as a material possessing favorable thermal characteristics suitable for industrial applications such as pipes and protective coatings, which required enhanced thermal resistance. The utilization of rice husk ash (RHA) waste imposes both environmental and economic impacts. RHA has the potential to reduce environmental pollution caused by waste and decrease the costs involved in material production. [ABSTRACT FROM AUTHOR]

Fenugreek (Trigonella foenum-graecum L.) microgreens is an underutilized vegetable with limited shelf life having good source of antioxidants, carotenoid as well as vitamins. The study deals with nutritional quality and optimization of a suitable passive modified atmosphere packaging (MAP) for improving the shelf life of fenugreek microgreens in its minimally processed form (MPFM) at 8oC Semipermeable plastic films viz., low density polyethylene, polypropylene, Cryovac PD 961® and stretchable PVC cling film with varying thickness were evaluated as packaging materials to obtain different MAP composition inside MPFM packages. Packaging of MPFM in 40 µm thick polypropylene film resulted in development of in-pack equilibrium MA with 10-14% oxygen and 5-8% carbon dioxide during storage. This in-pack MA maintained 'fresh-like' sensory properties, biochemical and nutritional quality in MPFM till 15 days of storage. Significant loss of B vitamins was recorded in all packages during low temperature storage. Packaging in 40 µm thick polypropylene film retained B vitamins significantly better than other semipermeable films. Low temperature storage in modified atmosphere conditions enhanced vitamin E content in MPFM. The outcome of the study will benefit the entrepreneurs and retailers for distant transport and storage of fenugreek microgreens in commercial open chillers maintained in supermarkets in their ready-to-cook form. [ABSTRACT FROM AUTHOR]

Linear low‐density polyethylene (LLDPE) and different concentrations (5‐20 wt%) of magnesium hydroxide (MAH) as a filler either with or without the addition of graphene nanoplatelets (GNPs) were peroxide cross‐linked using dicumyl peroxide as a cross‐linking agent in a twin‐screw extruder. The mechanical, thermal stability, flame retardancy, morphological, and rheological properties of the prepared samples were investigated. The mechanical properties of the peroxide cross‐linked LLDPE samples with higher MAH and GNP in the matrix were significantly improvement compared to neat LLDPE. This indicates that the addition of MAH and GNP to the peroxide cross‐linked LLDPE matrix could be suitable reinforcing fillers to achieve better and enhanced mechanical properties, particularly tensile strength. Conversely, a significant decrease in the elongation at break values was found for peroxide cross‐linked LLDPE samples compared to neat LLDPE. Similarly, results of thermogravimetric analysis revealed remarkable thermal stability enhancement in the peroxide cross‐linked LLDPE samples with higher MAH and GNP compared to neat LLDPE. The results from UL94 test demonstrated that the peroxide cross‐linked LLDPE samples comprising higher MAH with GNP exhibited improved V = 0 rating compared to poor no rating (NR) for neat LLDPE. Furthermore, the scanning electron microscope and digital images shown improved flame retardancy properties for these samples because of the formation of protective char layer on the sample surface. The complex viscosity for the peroxide cross‐linked LLDPE samples, at lower frequency, increased with increasing MAH loading and further addition of GNP compared to neat LLDPE. Highlights: Cross‐linked polyethylene with flame retardant (FR) and nanofiller were prepared.Effects of cross‐linking and FR on the final properties of the polymer were studied.20wt% FR with 3 phr nanofiller promoted the final properties of the polymer.Higher filler loading in the polymer improved flame retardancy and thermal stability.Combined effect of cross‐linking and FR has shown major improvement. [ABSTRACT FROM AUTHOR]

Microplastic pollution has become a global concern, with potential negative impacts on various ecosystems and wildlife species. Among these species, ducks (Anas platyrhynchos) are particularly vulnerable due to their feeding habits and proximity to aquatic environments contaminated with microplastics. The current study was designed to monitor microplastic (MP) pollutants in the freshwater ecosystem of the Panjkora River, Lower Dir, Pakistan. A total of twenty (20) duck samples were brought up for four months and 13 days on the banks of the river, with no food intake outside the river. When they reached an average weight of 2.41 ± 0.53 kg, all samples were sacrificed, dissected, and transported in an ice box to the laboratory for further analysis. After sample preparation, such as digestion with 10% potassium hydroxide (KOH), density separation, filtration, and identification, the MP content was counted. A total of 2033 MP particles were recovered from 20 ducks with a mean value of 44.6 ± 15.8 MPs/crop and 57.05 ± 18.7 MPs/gizzard. MPs detected in surface water were 31.2 ± 15.5 MPs/L. The major shape types of MPs recovered were fragments in crop (67%) and gizzard (58%) samples and fibers in surface water (56%). Other types of particles recovered were fibers, sheets, and foams. The majority of these detected MP particles were in the size range of 300–500 µm (63%) in crops, and 50–150 µm (55%) in gizzards, while in water samples the most detected particles were in the range of 150–300 µm (61%). Chemical characterization by FTIR found six types of polymers. Low-density polyethylene (LDPE) had the greatest polymer detection rate (39.2%), followed by polyvinyl chloride (PVC) (28.3%), high-density polyethylene (HDPE) (22.7%), polystyrene (6.6%), co-polymerized polypropylene (2.5%), and polypropylene homopolymer (0.7%). This study investigated the presence of microplastics in the crops and gizzards of ducks, as well as in river surface water. The results revealed the significant and pervasive occurrence of microplastics in both the avian digestive systems and the surrounding water environment. These findings highlight the potential threat of microplastic pollution to wildlife and ecosystems, emphasizing the need for further research and effective mitigation strategies to address this pressing environmental concern. [ABSTRACT FROM AUTHOR]

The pulse beetle Callosobruchus chinensis (L.) is a major pest of stored chickpea. In the present study, efficacy of neem (0.5 and 1.0%) and turmeric powders (0.5 and 1.0%) has been evaluated against this pest, in combination with mustard oil (0.3%), thermal treatment @ 60oC for 20 min and packing materials including open, PP (polypropylene) and LD (low density polyethylene). The results revealed increased efficacy with concentration of neem and turmeric powder. Use of neem oil @ 1.0%+ mustard oil @ 0.3% kept in open packing, proved to be significantly superior at four months of storage. Turmeric powder @ 0.5%+ mustard oil @ 0.3% treated grains showed a significantly better germination. Moisture content differed significantly with treated samples. The colour change and myroflora incidence were comparatively minimum with neem leaf powder @ 0.5%+ mustard oil @ 0.3% treated samples. Thermal treated grains proved superior compared to botanicals, whereas, colour change led to significantly lesser effect. Among the packings, PP and LD packed samples significantly influenced the infestation and germination irrespective of the botanicals. [ABSTRACT FROM AUTHOR]

The purpose of the present study is the estimation of the environmental degradation process of oxo-biodegradable polyethylene bags. The degradation process of polyethylene samples, with the addition of a d2w prodegradant, was studied under natural weathering, freshwater (pond), and water in laboratory condition for a period of 48 months. The impact of characteristic parameters of environments on the extent of degradation, monitored by weight changes, mechanical properties, and surface morphology, has been discussed. The degraded polymer samples were also analyzed by FTIR spectroscopy. It was established that the oxo-biodegradable polyethylene samples were hardly prone to degradation in natural freshwater, but more vulnerable to environmental weathering. Abiotic parameters (oxygen, temperature, solar radiation) played a more important role in the degradation process of oxo-biodegradable polyethylene than biotic parameters (microorganisms). Natural weathering led to first fragmentation of the polymeric samples after 18 months, weight loss to 81.6% after 39 months, and complete assimilation after 45 months. In the pond, 48 months incubation resulted in an increase in the weight of the samples (+19%) and a decrease in mechanical properties: tensile strength from 26.31 to 17.35 MPa and elongation at break from 304 to 31%. The biofilm formed on the polymer surface made it difficult for oxygen to reach the degraded material, so oxydegradation in the pond was slower. ATR-FTIR analysis and microscopic observations confirm the degradation taking place in natural environments. No visible degradation changes were observed in the oxo-biodegradable polyethylene after incubation under laboratory water, because of the lack of microorganisms and solar radiation. The degradation of oxo-biodegradable polyethylene in natural environments required a longer incubation time compared to the degradation time declared by the manufacturer. [ABSTRACT FROM AUTHOR]

A multilayered ternary solid polymer electrolyte (TSPE) is presented. First, the influence of polyethylene oxide degradation on cell failure, development of subsequent volatile degradation products, and cell impedance is analyzed. The low electrochemical stability window/oxidative stability (≥3.8 V) results in side‐chain oxidation and loss of active material. Subsequently, electrolyte stability is improved and a thin‐film (≤50 μm) TSPE with three functional layers is developed to match the wide‐ranging electrolyte requirements toward Li metal anodes and different cathode materials like LiNi0.6Mn0.2Co0.2O2 and LiFePO4 (NCM622, LFP). The high‐voltage stability of ≥4.75 V makes the TSPE a promising candidate in high‐voltage applications. Because of high Coulombic efficiencies in NMC622‖Li metal (99.7%) and LFP‖Li metal (99.9%) cells, the presented electrolyte enables stable long‐term cycling with great capacity retention of 86% and 94%, respectively. The temperature stability of >300 °C and the capability to prevent high surface area Li and dendrite formation (even at an areal capacity utilization of >40 mAh cm−2) contribute to high safety under a wide range of conditions. [ABSTRACT FROM AUTHOR]

This paper aims to examine physical and mechanical performances of a Reclaimed asphalt pavement (RAP) material reinforced with 5 to 15 mm size sheets of plastic waste. The three types of plastic used in the study are: low density polyethylene (LDPE), high density polyethylene (HDPE) and polyethylene terephthalate (PET) with 1%, 1.5%, and 2% dosage by weight of aggregates. Obtained Duriez test results testify to a 9% to 30% improvement in moisture resistance for all types of plastic compared to virgin mixture while for LDPE waste plastic type workability test attests an acceptable compaction condition for RAP material with less than 1.5% of waste plastic. Nevertheless, it has been noticed an increase in void index and compaction difficulties starting from 1.5% dosage, resistance to rutting has also improved with the addition of waste plastic, an improvement in fatigue strength was also observed particularly at 2% dosage. [ABSTRACT FROM AUTHOR]

The blue crab Callinectes sapidus Rathbun, 1896 is native to the western coasts of the Atlantic Ocean and is currently considered an invasive species in the Mediterranean Sea. In this study, we examined the stomach contents of C. sapidus to determine the frequency of occurrence of microplastics (MPs) and microfibers (MFs) in the Balearic Islands archipelago in the western Mediterranean Sea. A total of 120 individuals were collected from six locations between 2017 and 2020. Overall, 65.8% of the individuals had MPs and/or MFs particles with an average of 1.4 ± 1.6 particles ind.−1 of which an average of 1.0 ± 1.3 items ind.−1 were MFs and an average of 0.4 ± 0.8 items ind.−1 were MPs. In terms of type, fragments were the dominant type of MPs and the most common size of items ranged from between 0.5 and 1 mm (40%) followed by 1–5 mm (31%). The most prevalent polymers were low-density polyethylene (39%) and high-density polyethylene (26%). In terms of links to human activities, MP ingestion was positively correlated with an increase in drain pipes, whereas MF ingestion was positively correlated with an increase in sewage pipelines, providing evidence of potential sources and the bioavailability of these particles in various environments. This study confirms the widespread presence of MP and MF particles, even in areas that are currently managed under different protection statuses, in the stomach contents of invasive blue crab species throughout coastal communities. [ABSTRACT FROM AUTHOR]

The variety of polymers utilized in medical devices demands for testing of extractables and leachables according to ISO 10993‐18:2020 in combination with ISO 10993‐1:2018. The extraction of the materials involves the use of organic solvents as well as aqueous buffers to cover a wide range of polarity and pH‐values, respectively. To estimate patient exposure to chemicals leaching from a polymer in direct body contact, simulating solvents are applied to best mimic the solubilization and partitioning behavior of the related tissue or body fluid. Here we apply linear solvation energy relationship (LSER) models to predict blood/water and adipose tissue/water partition coefficients. We suggest this predictive approach to project levels of potential leachables, design extraction experiments, and to identify the optimal composition of simulating extraction solvents. We compare our predictions to LSER predictions for commonly applied surrogates like ethanol/water mixtures, butanol, and octanol as well as olive oil, butanone, 1,4‐dioxane for blood and adipose tissue, respectively. We therefore selected a set of 26 experimentally determined blood/water partition coefficients and 33 adipose tissue/water partition coefficients, where we demonstrate that based on the root mean squared error rmse the LSER approach performs better than surrogates like octanol or butanol and equally well as 60:40 ethanol/water for blood. For adipose tissue/water partitioning, the experimentally determined octanol/water partition coefficient performs best but the rmse is at the same range as our LSER approach based on experimentally determined descriptors. Further, we applied our approach for 248 extractables where we calculated blood/low density polyethylene (LDPE) and adipose tissue/LDPE partition coefficients. By this approach, we successfully identified chemicals of potential interest to a toxicological evaluation based on the total risk score. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution in agricultural soils, resulting from the use of plastic mulch, compost, and sewage sludge, jeopardizes the soil microbial populations. However, the effects of MPs on soil chemical properties and microbial communities remain largely unknown. Here, we investigated the effects of different concentration levels (0, 0.1, 1, 3, 5, and 7%; w:w) of low-density polyethylene (LDPE) MPs on the chemical properties and bacterial communities of agricultural soil in an incubation study. The addition of LDPE MPs did not drastically change soil pH (ranging from 8.22 to 8.42). Electrical conductivity increased significantly when the LDPE MP concentrations were between 1 and 7%, whereas the total exchangeable cations (Na+, K+, Mg2+, and Ca2+) decreased significantly at higher LDPE MP concentrations (3–7%). The highest available phosphorus content (2.13 mg kg−1) was observed in 0.1% LDPE MP. Bacterial richness (Chao1 and Ace indices) was the lowest at 0.1% LDPE MP, and diversity indices (Shannon and Invsimpson) were higher at 0 and 1% LDPE MP than at other concentrations. The effect of LDPE MP concentrations on bacterial phyla remained unchanged, but the bacterial abundance varied. The relative abundance of Proteobacteria (25.8–33.0%) was the highest in all treatments. The abundance of Acidobacteria (15.8–17.2%) was also high, particularly in the 0, 0.1, and 1% LDPE MPs. With the increase in LDPE MP concentration, the abundance of Actinobacteria gradually increased from 7.80 to 31.8%. Our findings suggest that different MP concentration levels considerably alter soil chemical properties and microbial composition, which may potentially change the ecological functions of soil ecosystems. [ABSTRACT FROM AUTHOR]

Grafting a voltage stabilizer on molecular chains of cross‐linked polyethylene (XLPE) can effectively improve the materials' insulation properties. Four different samples (XLPE, XLPE grafted with the voltage stabilizer, low‐density polyethylene (LDPE) blended with the voltage stabilizer, and LDPE grafted with the voltage stabilizer) are prepared in this paper. Several physicochemical and dielectric tests are performed to investigate the properties of the samples. The results demonstrate that the m‐aminobenzoic acid is successfully grafted onto the XLPE molecular chain. Moreover, the crosslinking and grafting processes are equally important for enhancing the materials' performance of the XLPE. In addition, the grafted voltage stabilizer negligibly affects the gel content and thermal properties of XLPE. However, it increases the crystallinity but decreases the lamella thickness. Moreover, the XLPE grafted with a voltage stabilizer has lower direct current (DC) electrical conductivity, less aggregation of space charge, and higher DC breakdown strength. The trap distribution results indicate that the voltage stabilizer introduces shallow traps in the sample and the quantum chemical calculations describe that the material bandgap is decreased. Thus, the high‐energy charge carriers are buffered by the newly‐introduced traps and the functional groups, leading to the enhanced material properties of the XLPE. [ABSTRACT FROM AUTHOR]

This study investigates the antimicrobial effectiveness of 405 nm light emitting diodes (LEDs) against pathogenic Escherichia coli O157:H7, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella Typhimurium, and Staphylococcus aureus, in thin liquid films (TLF) and on solid surfaces. Stainless steel (SS), high density polyethylene (HDPE), low density polyethylene (LDPE), and borosilicate glass were used as materials typically encountered in food processing, food service, and clinical environments. Anodic aluminum oxide (AAO) coupons with nanoscale topography were used, to evaluate the effect of topography on inactivation. The impact of surface roughness, hydrophobicity, and reflectivity on inactivation was assessed. A 48 h exposure to 405 nm led to reductions ranging from 1.3 (E. coli) to 5.7 (S. aureus) log CFU in TLF and 3.1 to 6.3 log CFU on different solid contact surfaces and packaging materials. All inactivation curves were nonlinear and followed Weibull kinetics, with better inactivation predictions on surfaces (0.89 ≤ R2 ≤ 1.0) compared to TLF (0.76 ≤ R2 ≤ 0.99). The fastest inactivation rate was observed on small nanopore AAO coupons inoculated with L. monocytogenes and S. aureus, indicating inactivation enhancing potential of these surfaces. These results demonstrate significant promise of 405 nm LEDs for antimicrobial applications in food processing and handling and the healthcare industry. [ABSTRACT FROM AUTHOR]

Metals are being replaced with high-performance and lightweight polymers, but their low thermal conductivity and poor electrostatic dissipative properties are significant problems. For the protection of sensitive electronic circuitry in automotive and aerospace parts, some device housing materials must provide electrostatic discharge and dissipate heat generated at higher rates as electronic circuits are increasingly miniaturized. Micro-texturing on the film surface can greatly enhance the heat dissipation area and was investigated in this study using low-cost graphite nanoplatelet (GNP)-filled LLDPE films. Micro-finned films (30 vol% GNP) having a 51 ± 10% larger heat-dissipation area were successfully produced using a continuous extrusion process. The through-thickness thermal conductivity of 30 vol% GNP-filled LLDPE was measured at 1.3 W/m·K, which represents a 200% improvement over that of pure LLDPE. For a GNP content of 30 vol%, the surface and volume electrical conductivity of the composite films also increased by 8 orders of magnitude (resistivity down from ≈1015 to 107 Ω·cm) and electrostatic decay time reduced to a below-resolution limit of 0.01 s, at par with military standard requirements. Thus, micro-fin textured GNP-LLDPE offers a unique combination of electrical and thermal transport desired for the protection of electronic encapsulation materials. [ABSTRACT FROM AUTHOR]

As a lifestyle habit, shoppers like to lick their fingers before opening the polyethylene (PE) shopping bag. In fact, this implies a scientific problem, that is, moisture has an impact on the friction behavior between the plastic bag and the surface of the finger skin. In this study, an experimental method was employed to measure skin friction at three different hydration levels. The high-density polyethylene (HDPE) and low-density polyethylene (LDPE) materials were performed, and photographs of fingertips touching PE films were recorded by a camera. The experimental results showed that the applied normal load is positively correlated with the friction force and negatively correlated with the friction coefficient. And moisture content will increase friction. Specifically, when the fingertip slides on the HDPE film, the friction coefficient of the water-soaked skin is 5.9 times that of the dry skin. It can be inferred that the decrease in modulus of elasticity, as well as volume expansion, leads to an increase in contact area when the skin is wetted with water. This is the main reason for the increase in finger friction. In addition, a negative power function model was established to describe the relationship between the coefficient and the friction conditions by considering the combined effects of hydration level, normal load and material. Abbreviations: CCD: Charge-coupled Device; COF: Coefficient of friction; HbA1C: Hemoglobin A1C; HDPE: High-density polyethylene; LDPE: Low-density polyethylene; PE: Polyethylene; SC: Stratum corneum; [ABSTRACT FROM AUTHOR]

Featured Application: This work is of particular interest in the design of products widely used in daily life, such as HDPE and LLDPE blend plastic bags. The aim of this study is to analyze how the main process parameters (BUR, TUR, and TR) affect the mechanical properties of this type of product, helping designers to adapt the production to customers' new requirements while maintaining the product properties. All the samples were manufactured on an industrial scale. The results are beneficial so that the highest tensile and impact properties can be obtained through minimal changes in the already mentioned process parameters, thus also reducing the amount of waste due to products manufactured outside the specification limits. Polyethylene plastic bags manufactured via blown film extrusion have different quality specifications depending on their intended use. It is known that the mechanical properties of a film depend on the process parameters established, but little is known concerning how they affect one another, even more so due to the variety of polyethylene materials and processing techniques. This study focuses on establishing a proper correspondence of important mechanical properties like the dart impact, tensile strength at break, and elongation at break with commonly used process parameters like the blow-up ratio, take-up ratio, thickness reduction, and neck height, for a high-density polyethylene hexene copolymer and a linear low-density polyethylene butene copolymer blend film. Because this polyethylene mixture is an anisotropic material, interesting R2 values equal to or higher than 0.90 were found: a BUR with elongation at break and tensile strength at break in the MD and TD, a TUR with elongation at break in the MD and tensile strength at break in the MD and TD, and a TR with elongation at break and tensile strength at break in the MD. Also, a relationship between the dart impact and both the neck height and thickness were found. [ABSTRACT FROM AUTHOR]

Polyethylenes endowed with low densities of in‐chain hydrolyzable and photocleavable groups can improve their circularity and potentially reduce their environmental persistency. We show with model polymers derived from acyclic diene metathesis polymerization that the simultaneous presence of both groups has no adverse effect on the polyethylene crystal structure and thermal properties. Post‐polymerization Baeyer–Villiger oxidation of keto‐polyethylenes from non‐alternating catalytic ethylene‐CO chain growth copolymerization yield high molecular weight in‐chain keto‐ester polyethylenes (Mn≈50.000 g mol−1). Oxidation can proceed without chain scission and consequently the desirable materials properties of HDPE are retained. At the same time we demonstrate the suitability of the in‐chain ester groups for chemical recycling by methanolysis, and show that photolytic degradation by extended exposure to simulated sunlight occurs via the keto groups. [ABSTRACT FROM AUTHOR]

With the concept of environmental protection is deeply popular, the power cables change from traditional thermosetting cross‐linked polyethylene (XLPE) cables to low‐carbon, environmentally friendly, recyclable polypropylene (PP) cables and the semi‐conductive shielding layer that matches the insulation layer for PP cables is highly valued. In this paper, LDPE is replaced with PP in the formulation of shielding layer of commercial XLPE cables. The physicochemical and electrical properties of PP/EVA/CB (PP‐based) and LDPE/EVA/CB (LDPE‐based) shielding layers were compared. The effect of interface matching characteristics on the electric field distortion was analyzed by finite element simulation software. The experimental results show that the volume resistivity of the shielding layers all tend to rise with the increasing temperature, but the resistivity of the PP‐based shielding layer has a smaller fluctuation. The PP‐based shielding layer has a smoother surface, while the space charge injected into the PP insulation layer is the lowest, about 0.433 × 10−7 C. Compared to the LDPE‐based shielding layer/insulation layer, the PP‐based shielding layer/insulation layer has a 50% reduction in interfacial electric field distortion rate. This work is an essential reference for the development for PP cables and their shielding layer selection. [ABSTRACT FROM AUTHOR]

Manipulation of insect foraging may provide the basis for effective insect pest control strategies. Recent laboratory and small‐scale greenhouse experiments have shown that a blend of styrene and benzaldehyde is attractive to some Aphidius parasitoids, making it a good candidate for attracting and retaining these natural enemies in cropping systems. However, an appropriate dispenser type and appropriate dose for field application and its attraction range have yet to be identified. In this study, we performed experiments to determine an appropriate dispenser type – Omnilure® vs. low‐density polyethylene (LDPE) bags – and the most suitable dose to attract Aphidius colemani Viereck (Hymenoptera: Braconidae) under commercial greenhouse conditions and to determine the maximum distance of attraction. A mixture of 10 mg styrene and 100 μg benzaldehyde was the most attractive dose for A. colemani when provided by the dispensers under greenhouse conditions. The highest percentage of parasitoids was attracted when insects were released at a distance of 0.5 m from the Omnilure dispensers. Nevertheless, compared to the solvent control the blend of styrene and benzaldehyde remained attractive over a distance of up to 5 m. The potential application of these results in novel augmentation biocontrol strategies is discussed. [ABSTRACT FROM AUTHOR]

Bubble nucleation and growth were investigated in low density polyethylene (LDPE) using nitrogen (N2). The solubility and diffusivity of N2 in low density polyethylene were determined by a magnetic suspension balance (MSB) system. The bubble nucleation and growth during foaming was assessed using a visualization batch foaming system. It was observed that the increase in temperature and pressure decrement, decreased the bubble density, respectively. The bubble size during the foaming was also studied through numerical model and the effect of various simulation variables on the bubble growth was investigated. It was concluded that the numerical model could predict the foaming process. Moreover, according to the bubble pressure profile, the N2diffusion are formative factors in controlling the bubble growth. [ABSTRACT FROM AUTHOR]

The study investigates changes in the mechanical, thermal, morphological and physical properties of recycled low density polyethylene (LDPE) composites made with percentages (10 wt%, 20 wt%, 30 wt.%) of old newspaper fiber (ONF) and waste engine oil (WEO) (1 wt.%). The composites were manufactured by a single screw extruder. Adding WEO up to 20 wt% of ONF had a positive effect on the flexural properties, while the incorporation of WEO up to 10 wt % of ONF showed an affirmative effect on the tensile properties of the composites. The highest flexural strength was achieved in A3 (13.19 MPa) and B3 (12.3 MPa) samples for ONF added composites and ONF/WEO composites, respectively. Adding to the WEO decreased the water absorption values of the recycled low density polyethylene composites. Differential scanning calorimetry analysis showed that the addition of 1% WEO, the crystallinity of the composites decreased to about 30%. In the light of the results, the WEO could be successfully used with old newspaper in a polyethylene matrix. Highlights: The highest tensile strength was achieved in the B3 sample (with WEO).The highest flexural strength was achieved in the B3 sample (with WEO).The highest tensile was obtained from the A3 sample (without WEO).The highest flexural strength was obtained from the A3 sample (without WEO).The crystallinity of the composites decreased to about 30%. [ABSTRACT FROM AUTHOR]

This study investigated the compatibility of waste plastic, a serious environmental and recycling concern, with styrene-butadiene-styrene (SBS) in asphalt binders. An extensive storage stability analysis of binders modified with varying dosages of low-density polyethylene (LDPE) from postcommercial usage with SBS as a compatibilizer and the understanding of behaviors of each component was conducted in this study. Although SBS-LDPE blends were stable with separation index in terms of G*/sin δ , percent recovery from multiple stress creep recovery (MSCR) detected nonhomogeneity of polymer dispersion in the asphalt blend. To address this nonhomogeneity, waste cooking oil was used to pretreat LDPE to enhance the dispersion and reaction with the binder. Ultimately, 4.5% SBS + 1.5% oil-treated LDPE (TLDPE) was observed to yield a stable SBS-TLDPE blend with a top-bottom separation index ratio of 1.0 in terms of G*/sin δ and percent recovery difference of 3.5% and 1.4% at 0.1 and 3.2 kPa, respectively. The study identified that the presence of LDPE negatively influences the recovery and cracking performance of asphalt binders at low temperatures. From critical temperature differential (ΔTc), Glover-Rowe (G-R) parameter and Black space diagrams at different aging levels, it was concluded that unlike SBS, SBS + LDPE combination had resistance against extended long-term aging. [ABSTRACT FROM AUTHOR]

Annually, the disposal of low-density polyethylene (LDP) and waste ceramics have increased, which have a negative impact on environmental pollution. Thus, construction material sustainability can be achieved through the use of these wastes in manufacturing concrete. This experimental investigation aimed to assess the behaviour of self-compacting concrete (SCC) incorporating LDP. A total of six concrete mixes were designed with various volume percentages of 0, 6, 12, 18, 24 and 30% of LDP as fine aggregate and used waste ceramic powder 30% (by weight) as partial substitution of cement for all mixtures. The experimental parameters are composed of fresh properties (fresh density, segregation analysis, H2/H1 ratio, slump flow diameter, V-funnel and T500 slump flow time) and hardened properties of dry density, ultrasonic pulse velocity, compressive and flexural strengths. However, the samples were exposed to elevated temperatures at 25 and 800°C for 3 h to examine dry density and compressive strength. The results showed that the dry density and compressive strength with 30% LDP were decreased by 4.9 and 37.17%, respectively, after being exposed to 800°C. From the compressive strength results, it was determined that all the mixes before and after exposure to elevated temperatures were suitable for structural purposes. [ABSTRACT FROM AUTHOR]

This research work was carried out with the aim of obtaining the optimum combination of the novel linear low-density polyethylene/ethylene vinyl acetate (LLDPE/EVA)nanocomposites by incorporation reduced graphene oxide (rGO) as reinforcement andLLDPE-g-MA as compatibilizerwith the new solution method.Different samples were synthesized by various amounts of rGO from 0.1 phr to 1 phr, 80 phr LLDPE, 5 phrLLDPE-g-MA, and 20 phr EVA.Thermal, rheological, mechanical, and morphological properties were investigated. Results showed that the modulus, elongation-at-break, and tensile strength increased significantly with the increase of rGO content in the presence of LLDPE-g-MA. Transmission electron microscopy (TEM) images showed that LLDPE-g-MA can cause a better dispersion of rGO in the polymeric matrix by creating an interface between LLDPE, LLDPE-g-MA, and EVA. In addition, the field emission scanning electron microscopy (FESEM) images showed that with the increase in the amount of rGO, the particlediameter of the EVA dispersed phase decreased significantly, which is the result of the interactions between the carbonic nanofiller and the LLDPE-g-MA compatibilizer. [ABSTRACT FROM AUTHOR]