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There are many photovoltaic (PV) applications where lighter weight and/or bendable PV power would be beneficial. This includes the curved surfaces of buildings, buildings with weight limitations, boats, automobiles, or other portable applications. In many of these cases, the bending will be only a single occurrence at installation or the amount of bending, even if repeated, is not dramatic. This allows for crystalline silicon modules to be used. For flexible applications, the dominant material for the frontsheet is polyethylene tetrafluoroethylene (PETFE). As a fluoropolymer it resists soiling, is UV stable, and PETFE is a more mechanically durable fluoropolymer. However, in the interests of keeping costs down, less expensive alternative polymers are desirable. In this study, highly accelerated ultraviolet light and heat stresses are applied to candidate materials and the degradation kinetics are determined to provide information to evaluate their suitability for use in a PV application.

Radiative cooling without energy consumption and environmental pollution holds great promise as the next-generation cooling technology. To date, daytime radiative cooling performance is still slightly low, especially in humid areas. In this work, we demonstrated that nanoporous polyethylene (Nano PE) film can improve solar reflectivity from 96% to 99%, thus boosting radiative cooling performance. Moreover, the experimental results in humid areas indicate that Nano PE films can improve radiative cooling performance by ∼76% in a clear day and 120% in a day with few clouds. Additionally, compared with ordinary PE films, thin Nano PE films have significantly higher weather fastness and mechanical strength. More importantly, nano PE films can scatter part of visible light, thus suppressing the generation of light pollution in practical applications. Lastly, the modeling results reveal that with Nano PE films, more than 95% of China's areas can achieve daytime cooling performance. Our work can boost the development of radiative cooling technology with a very low cost.

This research explores a segment of the mechanical, thermal & physical characteristics of a polymer polypropylene (PP) mixture including low density polyethylene (LDPE). There were mixing syntheses (pure PP, 25 LDPE/75PP, 50LDPE/50PP, 75LDPE/25LDPE, pure PP) that were examined. As outcome, the expansion of LDPE to PP has decreased, with improved thickness, elasticity, bending efficiency, versatile modulus and hardness. In a (25LDPE/75PP) arrangement the prevailing elasticity was achieved while the (50LDPE/50PP) synthesis was attributed to ideal bent efficiency. High density polyethylene (HDPE) blowing in different proportions PP/polyethylene (PEs) can remove sorting course employed during even recycling course. PP has interesting features like outstanding process ability &tolerance to chemicals. Inadequate versatility, however, limits its usage in specific applications. Mixing PP with relative PEs may enhance its versatility. Universal kinetics of PP crystallization have been affected greatly by the existence of PEs of various structures of the ramifications. Existence of LDPE reduced overall summation ratio while HDPE increased the process of crystallization. No negative effect was observed in the studied parameter range on mechanical performance and the related crystallinity.

Co-pyrolysis of lignin and waste plastics, for example polyethylene (PE), has been studied, but related reports are basically on condition optimizations. This study revealed a new perspective on PE-promoted lignin pyrolysis to phenolic monomers with mass transfer and radical explanation. Lignin and PE were first pyrolyzed individually to identify pyrolysis characteristics, pyrolytic products, as well as the suitable co-pyrolysis temperature. Then, co-pyrolysis of blended lignin/PE with various ratios was investigated. Yields of lignin products reached the maximum under lignin/PE ratio of 1:1, but blended approach always inhibited the production of lignin phenols. This resulted from the poor mass transfer and interactions between lignin and PE, in which PE pyrolysates could easily escape from the particle gaps. While in layered approach, PE pyrolysates had to pass through the lignin layer which contributed to the good interactions with lignin pyrolysis intermediates, thus the yields of lignin-derived products were significantly improved. Interactions between lignin and PE (or their pyrolysates) were mainly radical quenching reactions, and X-ray photoelectron spectrum (XPS) and electron paramagnetic resonance (EPR) of pyrolytic chars were conducted to verify these interactions controlled by mass transfer. The percentage of C C (sp2) and concentration of organic stable radicals in layered lignin/PE char were both the lowest compared with those in blended lignin/PE and lignin char, indicating the stabilization of lignin-derived radicals by PE pyrolysates. Moreover, the spin concentration of radicals in the char from layered char/PE was lower than that in lignin char, which further affirmed the quenching of radicals by PE in the layered co-pyrolysis mode.

Canola meal is a low-value agricultural residue obtained after oil extraction from canola, the utilization of which requires further attention. On the other hand, plastic waste disposal is also another leading issue that creates severe environmental challenges. Supercritical water gasification is considered an environmentally friendly technology to produce hydrogen from plastic residues and organic wastes. This study deals with hydrothermal co-gasification of canola meal and plastic wastes (i.e., low-density polyethylene) while exploring the influence of temperature (375–525°C), residence time (15–60 min) and plastic-to-biomass ratio (0:100, 20:80, 50:50, 80:20 and 100:0) on hydrogen yield. Maximum hydrogen yield (8.1 mmol/g) and total gas yield (17.9 mmol/g) were obtained at optimal temperature and residence time of 525°C and 60 min, respectively. A change in the gas yield with variable plastic-to-biomass ratio showed synergistic effects between both feedstocks. The trend of catalytic performance towards improving hydrogen yield was in the following order: WO3–TiO2 (18.5 mmol/g) > KOH (16.9 mmol/g) > TiO2 (9.5 mmol/g) > ZrO2 (7.8 mmol/g) > WO3–ZrO2 (7.4 mmol/g).

A series of laboratory tests were conducted to investigate the interface transmissivity, θ, between a 1.5 mm thick high-density polyethylene geomembrane (GMB) and a multicomponent geosynthetic clay liner (GCL) when permeated with a simulated municipal solid waste landfill leachate under a range of applied stresses (10–150 kPa). The effect of three different prehydration fluids, a 4 mm diameter central coating defect, coating defect position, and the effect of coating orientation of the GCL were investigated. It was found that at an applied stress of less than 70 kPa, the effect of these factors on θ was largely masked by the variability in the initial interface contact condition between the GMB and GCL. At 100–150 kPa, the effects of initial variability were largely eliminated, but there was no notable effect of other factors for multicomponent GCLs on interface transmissivity.

Molecular dynamics simulations have been performed to explore the underlying synergistic mechanism of pillared graphene or non-covalent connected graphene and carbon nanotubes (CNTs) on the mechanical properties of polyethylene (PE) nanocomposites. By constructing the pillared graphene model and CNTs/graphene model, the effect of the structure, arrangement and dispersion of hybrid fillers on the tensile mechanical properties of PE nanocomposites was studied. The results show that the pillared graphene/PE nanocomposites exhibit higher Young’s modulus, tensile strength and elongation at break than non-covalent connected CNTs/graphene/PE nanocomposites. The pull-out simulations show that pillared graphene by CNTs has both large interfacial load and long displacement due to the mixed modes of shear separation and normal separation. Additionally, pillared graphene can not only inhibit agglomeration but also form a compact effective thickness (stiff layer), consistent with the adsorption behavior and improved interfacial energy between pillared graphene and PE matrix.

The analysis of microplastics (MP) becomes more difficult for smaller sizes, especially in complex matrices such as sediment of natural waters. In this work, we analyzed MPs in sediment using laser direct infrared (LDIR) imaging, a relatively new technique in environmental MP studies. Sediment samples were spiked with analytical surrogates (polyethylene spheres), and subjected to density separation, wet peroxide oxidation, calcite removal, and filtration. The extracted particles were coated on to a low-emissivity glass slide which was first examined on a stereomicroscope. Six slides (two sediment samples and four different blanks) were further analyzed using an Agilent LDIR system. Approximately 520 and 430 MP/g were found in the two samples, with diameter ranging 20–3384 μm and 84% being smaller than 100 μm. The increase in particle count with decreasing particle sizes followed a power law curve, suggesting that a large portion of the smaller MPs was generated by the breakdown of larger plastic pieces. Major polymers found in this work included polyamide, polyester, polytetrafluoroethylene, and polyacetal. Most MPs were fragments, while beads and fiber were also found. In the two sediment samples, 14% and 46% of the total particles, respectively, were composed of non-plastic micro-sized particles, including natural polyamide, cellulose, chitin, rubber, and “unknown”. Challenges, potential biases, and uncertainties are discussed. This work is the first application of LDIR imaging on MPs in natural sediment.

Gadolinium (III)-based T1 contrast agent have been widely used in clinical MRI. In this study, salicylic acid-gadolinium chelate was prepared via directly coordination reaction of gadolinium ion and salicylic acid. Then, three polyethylene glycols with different molecular weight were modified on the surface of salicylic acid-gadolinium by simple chemical coupling to construct three core-shell structural Gd based composites. The SEM and TEM characterization results show that the composite is a spherical particle with a diameter of about 100–200 nm. The longitudinal relaxation rate r1 of the Gal-PEG-2000 is 11.097 (mmol/L)–1/s, and the ratio of r2/r1 is as low as 2.53. The composite shows good liver and intestines MRI performances after being used in in vivo imaging, showing a good prospect of biological application.

The research on jute fiber reinforced polymer composites is an emergent concern with the development of new materials due to their significant properties like economical, partially biodegradable, and environment friendly. It is wondered that the hydrophilic nature of jute fiber negatively affects the interfacial interaction with hydrophobic polymeric materials in the composite, which then affects the resultant mechanical, microstructural and physico-chemical absorption properties. In order to overcome this fact, researchers have carried out some techniques for fiber surface chemical treatments. On the other hand, due to the low processing costs and design flexibility, thermoplastics deal many benefits over thermoset polymers, and polyethylene shows excellent processing behaviors such as low density, low cost, considerable flex life, outstanding surface hardness, scratch resistance and good electrical insulator. Besides the traditional thermoplastic and thermosetting polymers, montmorillonite nanoclay is also receiving attention to manufacturing fiber polymer nanocomposites for industrial and household applications as well. This review is considered to highlight the progress of jute fiber reinforced polymer nanocomposites. The study also focuses on the several features of jute polymer composites and nanocomposites as a function of fiber chemical treatments.

Droplet-based microfluidic technology can be utilized as a microreactor to prepare novel functional monodisperse microcapsules. In this study, a droplet-based microfluidic chip with surface modification, which allowed the one-step preparation of double emulsion microcapsules. An O/W/O double emulsion using polyethylene (glycol) diacrylate (PEGDA) solution as the intermediate water phase was prepared by regulating the hydrophilicity and hydrophobicity of the chip surface, with PEGDA microcapsules prepared using UV polymerization. And then anti-tumor drug paclitaxel and neurotoxin 6-OHDA were encapsulated in microcapsules for drug and toxicology evaluation, respectively. Compared to controls, drug-loaded microcapsules caused a significant increase in the death rate of PC12 cells. This indicates that the obtained drug-loaded microcapsules could be used in drug evaluation and potentially in drug screening and delivery.

The most straightforward and potentially ideal route to produce polar-functionalized polyethylene is direct copolymerization of ethylene with polar monomers. However, access to high-molecular-weigh...

Low density polyethylene (LDPE) and high density polyethylene (HDPE) are the principal plastics present in solid plastic waste and are found out as the main components of microplastics in marine and terrestrial environments. Currently, efforts have been made to develop new and effective methods to ensure the identification and separation of plastics in waste, ensuring the necessary purity to obtain quality and economically competitive recycled products. In this contribution, we investigated the usage of Fourier-Transform Infrared Spectroscopy in attenuated total reflection mode (ATR-FTIR) combined with Principal Component Analysis (PCA), Linear Partial Least Squares Regression by Intervals (iPLS-R) and Competitive Adaptive Weighted Sampling (CARS/PLS-R) as chemometric methods to classify and determine the compositional fraction of the pristine and recycled mixtures of HDPE and LDPE from plastic waste in São Paulo, Brazil. The 3D PCA plots do not make it possible to classify the different polyethylenes and their polymer blends using the three Principal Components (PC), except for the 2D PCA diagram using PC1 and PC3. The iPLS-R presents the best predictive ability than CARS/PLS-R to determine the LDPE content in HDPE/LDPE recycled blends. However, the presence of different contaminants (in 5 wt%), such as silicon dioxide (SiO2), calcium carbonate (CaCO3), recycled polypropylene (PP), and recycled poly(ethylene terephthalate) (PET), reduces the potential usage of the iPLS-R models as identification tools for LDPE and HDPE sorting in industrial recycling processes.

All-solid-state lithium batteries (ASSLBs) employ high-capacity lithium (Li) metal as the anode and exhibit a higher energy density than that of conventional Li-ion batteries. However, the problems arose from the Li dendrites induce severely parasitic reaction between Li and electrolytes, leading to low coulombic efficiency (CE) and poor cyclic stability. Herein, a poly(vinylidene-co-hexafluoropropylene)/lithium nitrate (PVDF-HFP/LiNO3, marked as PFH/LN) artificial layer is employed to modified Li and achieve high CE ASSLBs with polyethylene oxide-Li6.4La3Zr1.4Ta0.6O12 (PEO-LLZTO) electrolyte. LN serves as a functionalized additive to facilitate the formation of a robust solid electrolyte interface (SEI), efficiently suppressing the formation of Li dendrites. Additionally, LN as a “binder” effectively links PFH with Li, providing good contact. PFH possesses high mechanical strength and moderate flexibility, which can not only physically inhibit the growth of Li dendrites, but also maintain the structural integrity of artificial layer over long-term cycles. Finally, Li/Li cells with such artificial layer demonstrate ultralong cycle life of 1800 and 1000 h under 0.2 and 0.4 mA cm–1, respectively. Furtherly, high CE can be achieved when applied in both LiFePO4 full cells and Li-Cu half cells. This work offers a facile and efficient strategy to greatly promote CE in PEO-based ASSLBs.

Aseptic loosening from implant-associated osteolysis in reverse shoulder arthroplasty (RSA) may contribute to premature implant failure. Although articular side polyethylene (PE) damage has been well documented in the literature, no studies to date have investigated backside wear in RSA. The aims of this investigation were to (1) document and compare the damage between the backside and articular surface in explanted RSA components, (2) assess whether certain quadrants have a greater propensity for damage, and (3) report the most common mode(s) of backside PE damage.Twenty-one RSA humeral liners retrieved during revision procedures between 2005 and 2014 were included for analysis. The mean time between implantation and extraction was 16 months (10 days-88 months). Diagnoses at the time of revision included dislocation (10), infection (4), mechanical failure (3), loosening (2), and unknown (2). Liners were examined under light microscopy (×10-30 magnification) and damage on the articular and backside of the liner surface was graded using the modified Hood score. The location and damage modality were compared between the articular side and backside of the implant.Damage was noted on the articular surfaces of all 21 liners and on the backside surface of 20 liners. The total damage in all the quadrants was higher on the articular surface than on the backside of the component, with a mean difference in total quadrant damage scores of 11.74 ± 3.53 (P.001). There was no difference in damage among the quadrants on the backside (P = .44) or the articular surface (P = .08). The articular side exhibited greater scratching, abrasion, and surface deformation than the backside (P.001).This short-term retrieval study demonstrated that backside PE damage occurs on the humeral component of RSA implants. There was greater damage to the articular side of the liner but wear to the backside was present in almost all liners. The clinical importance of backside wear in RSA and its overall contribution to PE particulate disease and osteolysis needs further investigation.

To increase the low yield and selectivity of aromatic hydrocarbons during the biomass pyrolysis process, we torrefied the biomass and then co-pyrolyzing with plastics such as high-density polyethylene (HDPE), polystyrene (PS), ethylene-vinyl acetate (EVA) and polypropylene (PP) and also single and dual catalyst layouts were investigated by Py-GC/MS. The results showed that non-catalytic fast pyrolysis (CFP) of raw bagasse (RBG) generated no aromatics. After torrefaction non-CFP of torrefied bagasse (TBG) generated low aromatic yield. Indicating that torrefaction would enhance the proportion of aromatics during the pyrolysis process. The CFP of TBG200°C and TBG240°C over ZSM-5 produced the total aromatic yield of 1.96 and 1.88 times higher, respectively, compared to non-CFP of TBG. Furthermore, the addition of plastic could increase H/Ceff. ratio of the mixture, consequently, increase the yield of aromatic compounds. Among the various torrefied-bagasse/plastic mixtures, the CFP of TBG/EVA (7:3 ratio) mixture generated the highest the total aromatic yield of 7.7 times more than the CFP of TBG alone. The dual catalyst layout could enhance the yield of aromatics hydrocarbons. The dual-catalytic co-pyrolysis of TBG200°C/plastic (1:1) ratio over USY/ZSM-5, improved the total aromatics yield by 4.33 times more than the catalytic pyrolysis of TBG200oC alone over ZSM-5 catalyst. The above results showed that the yield and selectivities of light aromatic hydrocarbons can be improved via catalytic co-pyrolysis and dual catalytic co-pyrolysis of torrefied-biomass with plastics.

A time-domain free-space technique has been proposed to extract relative permittivity (er) and effective conductivity (σe) of low-loss dielectric samples using their metal- and air-backed calibration-free reflected powers. Numerical computations and 3D electromagnetic simulations were performed to validate the method. A sensitivity analysis was carried out to examine its accuracy. Calibration-free time-domain free-space measurements over 1-12 GHz were conducted by VNA to extract er and σ e of polyethylene and polypropylene low-loss samples.

In this study, the catalytic co-pyrolysis (CCP) of wet-torrefied bamboo sawdust (TB) and linear low-density polyethylene (LLDPE) over zeolites was carried out using the thermogravimetric analyzer. The analysis was carried out at four different heating rates (5–40 °C min−1) and under an inert (Ar) atmosphere. Four degradation stages were observed in the CCP of TB and LLDPE blends, the first stage being moisture removal. The peak decomposition temperature of catalytic pyrolysis (CP) of LLDPE over FAU was reduced by 251 °C as compared to that over HZSM-5 and the enhancement can be attributed to the topology of HY. The activation energies were calculated using isoconversional models: Kissinger–Akahira–Sunose model (KAS), Ozawa–Flynn–Wall model (OFW), and Friedman model (FM). The average activation energies (Eα) of the blends TBL3:1, TBL1:1, and TBL1:3 (TBL: Blend of torrefied biomass and LLDPE) were 171, 128, and 117 kJ mol−1, respectively, using the KAS model. The Eα of the blends was much lower as compared to that of TB, indicating a clear synergism. A multistep mechanism was observed in both CP of individual samples and CCP of blends, as analyzed by Criado's master plot. For example, the CCP of TBL1:3 followed geometric (volume) contraction (R3) and first-order reaction models at low and high conversions, respectively.

The production of hydrogen (H2) from the pyrolysis–catalytic steam reforming of polyethylene, polystyrene (PS) and polyethylene terephthalate waste plastics was investigated using a two-stage reactor. The highest yield of hydrogen (125 mmol/gplastic) was obtained with PS at a catalyst temperature of 900°C and steam input weight hourly space velocity of 7.59 g/(h/gcatalyst) with a 10 wt% nickel/aluminium oxide (Ni/Al2O3) catalyst. Further investigation using PS showed that the process parameters of high catalyst temperature (900°C) and optimised steam input rate significantly increased the yield of hydrogen. Examination of several different catalysts (nickel/aluminium oxide, iron/aluminium oxide, copper/aluminium oxide, cobalt/aluminium oxide) showed that nickel/aluminium oxide had by far the highest catalytic activity and selectivity towards the yield of hydrogen.

An organic/inorganic hybrid coating consisting of molecular sieve (MS)/sulfonated melamine formaldehyde condensate (SMF) is fabricated on the polyethylene (PE) separator by a simple dip-coating process. The MS/SMF coating with high polarity enhances the electrolyte uptake of PE separator, and therefore favors higher ionic conductivity and Li+ transference number of separators. By regulating the ratio of MS/SMF, much higher Li+ transference number up to 0.5 can be obtained compared with the original PE separator (0.25). The PE separator possesses highest effective Li+ ionic conductivity when the ratio of MS/SMF is 3:1, which promotes more uniform Li+ deposition on the lithium metal surface for excellent lithium plating/stripping cycling stability up to 1000 h without any signs of short-circuit. Moreover, the functional PE separator possesses excellent H2O and HF capturing ability due to strong adsorption of MS and SMF for H2O and the scavenging of SMF for HF. The MS-SMF@PE separator-employed LiCoO2/Li unit cell shows superior C-rates capability and cycling performance, and no obvious lithium dendrite growth is found on the surface of lithium metal anode after cycling.

For side-chain liquid-crystalline polymers (SCLCPs) bearing calamitic mesogens, nematic and typical smectic (Sm) phases are expected. Here, using a precise polyethylene derivative with the biphenyl...

Polypropylene (PP) and polyethylene (PE) play central roles in our daily life. However, their immiscibility presents a major hurdle in both industry and academia when recycling them into alloys with favorable mechanical properties. Moreover, typical compatibilizer-enabled approaches are limited due to increased environmental concerns. Herein, inspired by a traditional Chinese technique, we report a facile, industry-scale methodology that produces a PP/PE binary blend with a highly ordered honeycomb nanostructure without any additives. Due to its nanostructure, the blend exhibits enhanced tensile properties in comparison with the parent components or with a sample prepared using an internal mixer. This approach has potential for applications not only in immiscible polymer blending, but also in non-sorting, compatibilizer-free waste plastics recycling. Through this technique, we expect that an environmentally friendly and sustainable plastic wastes recycling avenue can be found, and great economic benefits can be gained.

Recycling of plastic waste is an effective way that could prevent our planet from drowning in plastic pollution. The work presents chemical vapor deposition (CVD) growth of single-walled carbon nanotubes (SWNTs) from plastic polymers, including low-density polyethylene (LDPE) and polypropylene (PP). The successful synthesis of SWNTs from the polymers is attributed to the robustness of the designed cobalt catalyst supported by porous magnesia (Co-MgO), the porosity of which constrains the mobility of reduced Co nanoparticles, thus facilitating the nucleation of small diameter SWNTs. In addition, the approach is extended for catalyzing the production of SWNTs from plastic wastes, such as food packaging film and mask melt-blown filter. The proof-of-concept advance demonstrates the potential of plastic waste itself as feedstock for the production of high-value carbon nanomaterials.

Three groups of ultra-high-molecular-weight polyethylene (UHMWPE) with optimum hydrophilicity were obtained by halogenation modification. They were immersed in a 15% KBr solution for 30 h, a 10% NH...

In households, considerable costs are related to energy losses, which are a consequence of maintaining comfortable living temperatures. Improved isolation and utilization of energy harvesting devices is the key to reducing energy losses and the related costs. Polymeric solar absorbers are cost-effective solar energy harvesters that can significantly reduce the energy cost for individual households. One of the concerns related to polymers is their flammability. To mitigate the flammability risk, the present work explores the development of solar absorber paints with flame-retardant properties. Bridged 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivatives (NED and PHED) in concertation ranges of 10–15 wt% were used in a polyurethane-based matrix to demonstrate the effect of additives on the fire retardancy of the material. Additionally, the rheological and thermal properties of the composite materials were evaluated and described. Furthermore, aluminium and PPS (polyethylene sulphide) substrates were coated with solar absorber paint based on a 15% FR (fire retardant) additive formulation, for which the thermal stability at 150 °C for 655 h was evaluated. It was discovered that PHED is more compatible with the polyurethane matrix than NED, and as expected, a greater amount of FR additives resulted in improved flame retardancy. The long-term stability of absorber paint coatings on Al and PPS was also successfully confirmed by confirming stable solar absorptance and thermal emittance. In future prospects, we believe that the flame retardancy of polyurethane-based coatings could be further improved, and the utilization of covalently bonded FRs should also be considered.

A highly sought-after objective of Space Agencies is the development of additive manufacturing (AM) technologies and of multifunctional materials, key elements to future exploration and colonization of Moon and Mars. The 3D printing process via fused filament fabrication (FFF) is increasingly viewed as an interesting approach for the in-situ manufacturing of buildings and items using regolith as a feedstock material, enabling the necessary repair and recycling capabilities to ensure crew safety. In this work, we investigate the radiation shielding properties and the FFF 3D printing process of polyethylene-based composites filled with Martian regolith. The on-line tool for the assessment of radiation in space (OLTARIS) software developed by NASA was used to assess the radiation shielding effectiveness of polyethylene (PE)/regolith (RG) composites in the Martian radiation environment. A basalt powder with chemical composition similar to that of Mars soil was used as Martian regolith simulant in the 3D printing process. Differential scanning calorimetry (DSC) was used to determine the melting properties and crystallization degree of PE/RG composites at different RG concentrations, in order to analyze the effect of the simulant on the process parameters of filament extrusion and 3D printing. Low-impact Izod tests were also performed, with all PE/RG composites showing improved impact strength with respect to neat PE. Based on the DSC and Izod tests results, filaments of PE/RG composites were fabricated and used to 3D-print samples for tensile tests and 3-point bending tests. Results demonstrate the radiation shielding effectiveness of PE/RG composites and the capability of 3D-printers based on FFF to successfully manufacture components made of PE/RG composites starting from extruded filaments.

The extremely increasing amount of plastic waste due to the development of human society, economics and urbanization is an emergency task that must be urgently handled in order to reduce environmental problems. Although the plastic wastes can be converted to alternative liquid fuels through pyrolysis process, the compositions in the pyrolysis oil depended on the chemical structure of raw materials and pyrolysis condition affect its quality. Thus, this research aimed to comparatively investigate the production of alternative liquid fuels obtained from mixed plastics containing polystyrene (PS)/polyethylene terephthalate (PET)/polyethylene (PE)/polypropylene (PP) at 20/5/35/40 (w/w) via non-catalytic cracking (under N2 atmosphere), non-catalytic hydrocracking (under H2 atmosphere), and catalytic hydrocracking over 10 wt% Ni/SBA-15 catalyst conducted at an atmospheric pressure and 650 °C for 1 h. The product yields and chemical compositions (paraffins, olefins, aromatics and PAHs) in the liquid products generated from these processes were investigated and also compared to ones obtained from the non-catalytic processes of each plastic. Herein, the characteristics of 10 wt% Ni/SBA-15 catalyst was analyzed by N2-adsorption/desorption, X-ray diffraction (XRD), and H2-temperature programmed reduction (H2-TPR). The results indicated that the non-catalytic processes of PS provided the highest content of oil and wax product (ca. 92 wt%). Whereas, the non-catalytic hydrocracking of the mixed plastics gave the lowest one (ca. 69 wt%). However, the catalytic hydrocracking over 10 wt% Ni/SBA-15 catalyst (2.5 – 10.0 wt% based on the mixed plastics) could suppress the cracking and yielded the higher amount of oil and wax to ca. 76–80 wt%. To consider the chemical compositions in the liquid phase, the PAHs formation was relied on the aromatic structure in the feedstocks. The liquid product derived from the non-catalytic processes of PS contained the highest amount of PAHs compounds (2622–2926 ppm) followed by the mixed plastics. When the 10 wt% Ni/SBA-15 catalyst was applied to the catalytic hydrocracking of the mixed plastics, the amount of PAHs in the liquid product decreased from 1621 ppm to ca. 1000 ppm (30 – 40% PAHs reduction) without the reduction of heating value when compared to one obtained from the non-catalytic processes.

The establishment of a method of separation of materials from Tetra Pak waste to obtain products for use as raw material, fuel or other purposes was investigated in this study. First, the feasibility of hydrothermal treatment for the production of a solid fuel (hydrochar) and solid fraction formed by polyethylene and aluminum, called composite was analyzed. The results indicated that hydrothermal treatment performed at 240 ◦C yield the formation of hydrochar with good properties for its use as fuel and a composite of polyethylene and aluminum. The best conversion and separation of the cardboard and polyethylene/aluminum were obtained using 120 min as operating time. Then, the recovery of the aluminum fraction from the composite by using spent olive oil waste was studied. A partial separation of the composite layers (polyethylene and aluminum) was accomplished with improved aluminum purity for higher operating temperatures. Finally, the operating conditions of the pyrolysis process for the production of a solid (char) and high purity composite (aluminum) were optimized. The characterization results indicated that both char and aluminum resulting from the pyrolysis of the Tetra Pak at 400 ◦C still have a significant amount of polyethylene while higher purity levels of aluminum can be obtained at temperatures equal of higher than 500 ◦C.

A reliable and well-characterized dosimetry system which is traceable to the international measurement system, is the key element to quality assurance in radiation processing with cobalt-60 gamma rays, X-rays, and electron beam. This is specifically the case for health-regulated processes, such as the radiation sterilization of single use medical devices and food irradiation for preservation and disinfestation. Polyethylene is considered to possess a lot of interesting dosimetric characteristics. In this work, a detailed study has been performed to determine the dosimetric characteristics of a commercialized high-density polyethylene (HDPE) film using Fourier transformed infrared spectrometry (FTIR). Correlations have been established between the absorbed dose and radiation induced infrared absorption in polyethylene having a maximum at 965 cm−1 (transvinylene band) and 1716 cm −1 (ketone-carbonyl band). We have found that polyethylene dose-response is linear with dose for both bands up to1000 kGy. For transvinylene band, the dose-response is more sensitive if irradiations are made in helium. While, for ketone-carbonyl band, the dose-response is more sensitive when irradiations are carried out in air. The dose-rate effect has been found to be negligible when polyethylene samples are irradiated with electron beam high dose rates. The irradiated polyethylene is relatively stable for several weeks after irradiation.

In the present work the drying characteristics and proximate analysis of turkey berry (Solanum torvum) were analyzed under open sun drying and greenhouse drying with two different glazing materials (UV Polyethylene sheet and Drip lock sheet) under passive and active modes. The drying rate under different modes of drying are 18.73g/h in drip lock greenhouse active mode,12.50 g/h in UV polyethylene sheet greenhouse active mode,15.22 g/hin drip lock sheet greenhouse passive mode, 11.84 g/h in UV polyethylene sheet greenhouse passive mode and 10.65 g/h in open sun drying. Twelve mathematical models were chosen to determine the drying characteristics of Turkey berry. From the statistical analysis it is found that Modified Henderson and Pabis model is the best drying model describing thin layer drying characteristics of turkey berry in both open sun drying and green house drying. The goodness of the fit achieved is based on the values of coefficient of determination(R2), sum square error(SSE), root mean square error(RMSE) and reduced chi square (χ2).From the proximate analysis of dried turkey berry it is found that more amount of carbohydrate is retained in UV polyethylene greenhouse dryer under passive mode. In drip lock greenhouse dryer under passive mode the retention of vitamins such as protein, vitamin C and ash content showed a positive sign. In drip lock greenhouse dryer under active mode the retention of calcium, iron and dietary fibre is found to be high. Finally it is observed that more amounts of nutrients are retained in greenhouse drying than in open sun drying.

Due to their likeness in composition to natural tissues, synthetic hydroxyapatite (HA) nanoparticles have good biocompatibility, bioactivity, and osteoconductivity and have large applicability in a wide range of fields such as in tissue replacement, drug/gene delivery carriers, and biocompatible coatings. In this study, we synthesize hydroxyapatite by double decomposition method, we carried out the reactions in a water–ethanol medium at pH = 12 and room temperature. Its ceramization and the effect of sintering temperature and forming technique of this ceramic on the chemical and structural behavior, and compare it to natural hydroxyapatite extracted from bovine bones. According to the results obtained from the structural and morphological characterization techniques, the elaborate hydroxyapatite is similar to natural hydroxyapatite and can be used as a bone substitute. The HA powders obtained are modified by different levels of polyethylene. The characterization by different techniques (infrared; DRX; SEM, etc.). All the results of this work allow on the possibility of using these materials in the biomedical field such as in tissue replacement, drug/delivery carriers.

When utilised in arthroplasty applications, ultra-high-molecular-weight polyethylene (UHMWPE), the gold standard material for artificial joints, creates wear debris. The life of UHMWPE joints is generally restricted to 15–20 years due to unfavourable interactions of wear debris with surrounding tissues. Various attempts have been made in recent decades to enhance the material's wear resistance and performance. This study looks at the changes that have been made to increase its mechanical characteristics and wear resistance. Functionalization techniques, enhanced surface or bulk properties, and their various applications in medical implant fields (total hip arthroplasty, bone tissue engineering, joint implants) have all been extensively studied. A descriptive study of pure UHMWPE and its composite has been conducted in order to functionalize the features of medical implants.

In the present study, we investigated the possibility of value-added recycling of ultrafine ground tire rubber (uGTR) produced from water jet milling, with an average particle size of a few tens of microns. Our goal was to compare the properties of blends with different uGTR and conventional fine ground tire rubber (fGTR) contents prepared by blending with low-density polyethylene (LDPE). We also aimed to explore the property changes caused by the larger specific surface area due to the size effect. Samples were prepared with a hydraulic press after internal mixing. In the case of ground tire rubber (GTR) filled mixtures, the tensile properties showed rubber-like characteristics: with a significant decrease in modulus, elongation at break remained high, and tensile strength slightly decreased. The fracture surfaces of the samples were analyzed by scanning electron microscopy (SEM), wherein the case of materials made with uGTR showed better adhesion between the phases. In order to investigate the interfacial adhesion between the GTR and LDPE, we performed dynamic mechanical thermal analysis (DMTA). The glass transition peak of the uGTR shifted to a higher temperature and the storage modulus was higher than in the case of samples containing fGTR. Finally, we determined the Shore D hardness of the materials, which decreased with increasing GTR content, but hardness was greater in the case of uGTR samples. The better mechanical properties of blends containing uGTR were explained by better interfacial adhesion between the two phases due to the significantly higher specific surface area compared to fGTR.

The disposal of non-biodegradable materials like polyethylene, tetrapak etc have been a severe threat to the surrounding environment especially in developing/ under developing countries. Out of that, the polyethylene materials are commonly used to pack food and essential commodities like milk, curd, ghee, oil, snacks etc. After usage of these products, the polyethylene packs are left as solid wastes which was disposed either incineration or by dumping as landfills. An effort to find useful application of those polyethylene material wastes is on one side. In other side the existing pavements are not able to withstand the increase in traffic loads and thereby results to premature failure causing various pavement distress. In these aspects, to explore new suitable and sustainable alternative bituminous mix is a demanding need. In order to address both these issues, the present study investigated the suitability of polyethylene wastes in to the bitumen concrete mix. For this study, the polyethylene wastes of milk packets are shredded to a varying length of 1.5 cm, 3 cm, and 6 cm are mixed in dry pieces with the heated aggregates at temperature of 150–170 °C. Marshall specimen of bituminous concrete with and without shredded polyethylene wastes are prepared and tested as per the standard procedure. The Marshall characteristics like Marshall Stability, flow value, unit weight, air voids etc are determined. Based on the performance evaluation, all the Marshall characteristics of the mix are found to be satisfied for the utilization of shredded polyethylene waste strip 3.0 cm at 0.5% by weight of aggregate for both bitumen content 5% and 6%.

Biologically synthesized surfactant are commercially used in various biotechnology sectors as cosmetic, cleaning, and agriculture products. In this study, Bacillus paramycoides was isolated as new bacterial strain from plastic disposal site of Banasthali Vidyapith (Rajasthan) for producing lipopeptide biosurfactant. Surface tension, emulsification index, oil-displacement are some primary screening methods done to validate the production of biosurfactant. The emulsification analysis elucidated at 62.50% and reduction of surface tension noticed at 33.10 mN/m. The nano-encapsulation of this biosurfactant onto silver nanoparticles had efficiently improved its ability for biodegradation of polyethylene. UV sterilized polyethylene films were treated with biosurfactant mediated silver nanoparticles and its maximum degradation was observed within 70 days. The synthesized silver nanoparticles were characterized by UV spectrum, zeta size potential, scanning electron microscope analysis. The total weight loss of low-density polyethylene (cling films) and high-density polyethylene (grocery bags) was observed 36.30% and 31.11%, respectively after treatment with silver nanoparticles for these lipopeptide biosurfactant. The higher degree of biodegradation rate of LDPE and HDPE polyethylene after treating with silver nano-biosurfactant might be due to their high degree of biocompatibility and stability. These nano-biosurfactant could be effectively used for biodegradation of plastic pollutant at large scale.

Plastic waste is accumulated in recent years, causing environmental problems, particularly in developing nations. Recycling this waste as building materials is considered as a feasible solution to the environmental issue, but it is also a feasible solution to the issue of building economic design. This research aims to study the possibility of using plastic waste in the manufacture of unconventional bricks that are light in weight, environmentally friendly, inexpensive, and as an alternative to traditional bricks made from fossilized clays for use in the construction industries. In this paper, we use the remnants of medical syringes made of low-density polyethylene and two types of additives were added sawdust and sand in different proportions. The melting and moulding process was used in manufacturing. Testing has been conducted to identify hardness, density, water absorption, compressive strength and also to determine morphology properties by FTIR and SEM. The results showed that bricks made of plastic and sawdust gave a high compressive strength of 66Ϻpa at 20% of sawdust higher than bricks made of plastic and sand with a value of 61Ϻpa at 60% of sand. In both cases, they gave a higher compressive strength than ordinary bricks, as well as a very low absorption rate. The density was very low, especially with sawdust, where the highest value was 0.8985 g/cm3of pure polymer, and for sand, it was 1.4321 g/cm3 at 60% of sand and it gave good hardness values. The FTIR results showed that there is no chemical reaction, but only a physical reaction between the polymer and the additives, and through SEM, it was observed that there is homogeneity between the polymer and the additives. As a result, the study presents a new line of investigation into the sustainable recycling of the circular economy of waste thermoplastics.

Natural fibres now a days replacing the conventional structural materials such as Aluminium, steel, wood etc. with their excellent weight to strength ratio and with their high mechanical properties. In this present investigation hybrid composites were fabricated using Hand layup process using the natural fibres such as Banana, Coconut, Jute and Cotton fibres reinforced with Polyethylene at different weight proportions of 5, 8, 10, 12, 15, 18, 20 wt%. Tests such as water absorption, flexural rigidity, tensile, hardness and few other mechanical tests were conducted on the hybrid natural fibre reinforced composites. Among the hybrid composites the coconut fibre with 20 wt% and banana fibre with 18% shows high tensile strength with 56.4 N/mm2 and 54 N/mm2 and flexural strength. Water absorption is less in the hybrid composite with coconut and cotton fibres as reinforcements and gains mass of 5gm and 7gm.

Curcumin and Fenugreek essential oil (FEO) were blended into the PLA matrix by solution casting technique to improve the functional properties of the composite film. Both fillers (curcumin and FEO) were properly combined and uniformly distributed in the polymer matrix to create a PLA-compatible composite evidenced by Scanning electron microscope (SEM) and Fourier Transform Infrared (FT-IR) results. The addition of FEO and curcumin to the composite film improved UV-blocking, surface color, tensile strength, flexibility, thickness, and Water contact angle (WCA). However, the inclusion of curcumin and FEO slightly diminish the Water vapor permeability (WVP) while maintaining its thermal stability. The PLA-based composite film exhibited good antibacterial and anti-oxidant properties. In addition, a food quality test was performed on strawberry, and the results were compared to the commercial (polyethylene) film.

In the recent decade, there has been an increase in global warming, environmental changes, and other issues. Environmentally friendly products, such as natural composite materials, are being developed by researchers and academics to protect life on the planet. The purpose of this research is to see if cellulose and cellulignin fibres obtained from sugarcane bagasse (SCB) waste may be used as reinforcing filler in a thermoplastic polymer matrix. The injection method was used to create the low density polyethylene (LDPE) and sugarcane bagasse (SCB) composites. Fiber loading was set to be varied from 10 to 30 wt%. To improve interfacial bonding, the fibres were chemically modified using an alkali treatment, and the effects on the fiber/matrix interaction were evaluated using scanning electron micrographs (SEM). Tensile, impact, and hardness were used to determine the mechanical properties and corrosion tests. The findings revealed that sugarcane bagasse fibers, like other natural fibers, strengthen polyethylene. It has been found that the tensile strength and tensile modulus of the treated SCB fibers have been improved significantly by about 13% and 196%, respectively, compared to neat LDPE. This was due to the observed enhancement in the interfacial adhesion between the fiber and matrix. The impact resistance and hardness of the composite enhanced by 55.28% and 26%, respectively, over neat LDPE. According to SEM analysis, the alkali treatment affected the morphology of fibers.

At present, there is a vital need for river water purification by developing new approaches to eliminate bacterial biofilms, textile dyes, and Low-Density Polyethylene (LDPE) plastics that pose severe threats to human and environmental health. The current work put forward the construction of an eco-friendly green strategy to synthesize zinc oxide nanoparticles (ZnO NPs) using areca nut (Areca catechu) extract and their application to tackle the challenges in water purification. Prepared biogenic NPs were characterized by X-ray diffraction analysis (XRD), Fourier Transform Infra-Red (FT-IR), Energy Diffraction Spectroscopy (EDS), Scanning Electronic Microscopy (SEM), Transmission Electron Microscopy (TEM) analysis, confirmed the spherical shape in 20 nm and UV–vis spectroscopy. The characteristic absorption band exhibited at 326 nm confirmed the formation of ZnO NPs using UV–vis spectroscopy. Among all the tested bacterial pathogens, the E. coli at 50 µg/mL concentration showed the highest inhibition of biofilm activity, followed by the highest growth curve, cellular leakage, and potassium ion efflux. The ZnO NPs observed with photo-degradation of Rhodamine-B (Rh-B), Methylene Blue (MB), and Nigrosine dyes under sunlight irradiation at different time intervals. Finally, the photocatalytic activity of LDPE-ZnO NPs nanocomposite film showed the highest degradation under solar light irradiation were confirmed through photo-induced weight loss, SEM, FTIR, and MALDI-TOF analysis. This study demonstrates ZnO NPs exhibit efficacy against biofilm formation, degradation of photocatalytic textile dyes, and low-density LDPE film under solar light irradiation, which can be a step forward in water purification.

Aims The aim of this study was to investigate whether wear and backside deformation of polyethylene (PE) tibial inserts may influence the cement cover of tibial trays of explanted total knee arthroplasties (TKAs). Methods At our retrieval centre, we measured changes in the wear and deformation of PE inserts using coordinate measuring machines and light microscopy. The amount of cement cover on the backside of tibial trays was quantified as a percentage of the total surface. The study involved data from the explanted fixed-bearing components of four widely used contemporary designs of TKA (Attune, NexGen, Press Fit Condylar (PFC), and Triathlon), revised for any indication, and we compared them with components that used previous generations of PE. Regression modelling was used to identify variables related to the amount of cement cover on the retrieved trays. Results A total of 114 explanted fixed-bearing TKAs were examined. This included 76 used with contemporary PE inserts which were compared with 15 used with older generation PEs. The Attune and NexGen (central locking) trays were found to have significantly less cement cover than Triathlon and PFC trays (peripheral locking group) (p = 0.001). The median planicity values of the PE inserts used with central locking trays were significantly greater than of those with peripheral locking inserts (205 vs 85 microns; p < 0.001). Attune and NexGen inserts had a characteristic pattern of backside deformation, with the outer edges of the PE deviating inferiorly, leaving the PE margins as the primary areas of articulation. Conclusion Explanted TKAs with central locking mechanisms were significantly more likely to debond from the cement mantle. The PE inserts of these designs showed characteristic patterns of deformation, which appeared to relate to the manufacturing process and may be exacerbated in vivo. This pattern of deformation was associated with PE wear occurring at the outer edges of the articulation, potentially increasing the frictional torque generated at this interface. Cite this article: Bone Joint J 2021;103-B(12):1791–1801.

Solar-driven photocatalytic reduction of CO2 into value-added fuel is an exciting concept that can address serious global challenges such as greenhouse effect and energy crisis. However, the low sunlight utilization by the photocatalysts and their high production costs have greatly hindered their mass adoption. Herein, we proposed a facile and efficient approach to prepare the carbon nano-layer coated TiO2 as an efficient photocatalyst for the photocatalytic reduction of CO2 into CH4 and CO. By pyrolyzing linear low-density polyethylene, a carbon nano-layer was formed on the surface of TiO2. The obtained carbon nano-layer coated TiO2 was able to exhibit superior photocatalytic CO2 reduction activity as compared to its unmodified counterpart, whereby, a CH4 production rate of ~2.30 μmol · g−1 h−1 was achieved (prepared at a dwelling temperature of 600 °C). Meanwhile, a CO production rate of ~16.76 μmol · g−1 h−1 was recorded for the materials prepared at a dwelling temperature of 500 °C. The enhanced CH4 and CO production can be attributed to the elevated absorbance in the visible-light region, decreased band gap and effective restriction of photogenerated electron-hole pair recombination. Thus, based on the results, carbon nano-layer coated TiO2 can be a promising alternative for the photocatalytic reduction of CO2 into valuable fuel for large-scale application.

Bio-derived polyethylene furanoate (PEF) has recently gained attention as a sustainable alternative to polyethylene terephthalate (PET), amidst environmental concerns over fossil fuel depletion. He...

Solar-driven interfacial evaporation (SIE) is very promising to alleviate the freshwater scarcity issue. However, salt deposition on the sample surface will reduce evaporation performance, and compromised light absorption will result in a low water collection rate in conventional SIE apparatuses. Here, we report the design of a separated SIE system composed of a polypyrrole@Co3O4@aluminum sheet and a T-shaped superhydrophilic polyethylene/polypropylene nonwoven fabric right under the sheet. The photothermal surface exposed outside the closed SIE system is separated from the evaporation surface. Thus, salt fouling of solar evaporators is thoroughly avoided and the freshwater collection rate is greatly enhanced. Compared with conventional SIE systems, the separated SIE system has many advantages: simultaneous water and salt collection, a long-term stable evaporation rate even for concentrated brine (1.25 kg m-2 h-1 under 1 kW m-2 (1 sun) illumination, 15 wt % NaCl(aq), ≥120 h), high salt collection efficiency (≥97%), and a high water collection rate under natural sunlight, e.g., 0.72 kg m-2 h-1 in early spring (0.5-0.6 sun, 19-24 °C) and 0.33 kg m-2 h-1 in cold winter (0.3-0.4 sun, -6 to 4 °C). We foresee that the separated SIE system holds great potential for practical freshwater and salt collection from seawater.

Waste plastics recycling and oil/organics remediation are environmental issues of global concern. In this work, a protectant was introduced, for the first time, to make highly efficient catalysts for pyrolysis of waste plastics into carbon nanotubes (CNTs) with high yield. By using waste polyethylene, Co(NO3)2 and oleylamine respectively as carbon source, catalyst precursor and protectant, a yield as high as 59.0% was achieved. The CNTs exhibited a high adsorption capacity for methylene blue (up to 107.1 mg/g). Furthermore, by combining the CNTs with graphene oxide, a graphene-CNT aerogel with a low density of 8.2 mg/cm3 and high porosity of 96.0% was successfully prepared. It showed excellent hydrophobicity and mechanical stability, as well as high adsorption capacity of 289–410 g/g oil/organic solvent, which was much higher than most of these achieved by carbon-based three-dimensional materials reported previously, making the as-prepared aerogel a very promising adsorbent for oil/water separation.

The osteochondral lesions and osteoarthritis-related complications continue to be clinically relevant challenges to be addressed by the biomaterials community. Hydrogel-based scaffolds have been widely investigated to enhance osteochondral regeneration, but the inferior mechanical properties together with poor functional stability are the major constraints in their clinical translation. The development of osteochondral implants with natural tissue-mimicking mechanical properties remains largely unexplored. In this perspective, the present study demonstrates a strategy to develop a bilayer osteochondral implant with an elastically stiff composite (poly(vinylidene difluoride)-reinforced BaTiO

Geocells are three-dimensional expandable panels composed of polymers such as polyolefin polymers. Currently, geocells are being extensively used in various geotechnical engineering applications; however, its applications are limited because of the sizeable long-term deformation under constant loading and poor tensile strength. Owing to the rapid growth rate of geocells, it has become necessary to develop a polymer material with excellent creep resistance and tensile strength. To this end, a polymer-blend geocell (PBG) is developed in this study using a twin-screw extruder with high-density polyethylene (HDPE), polyamide 6, and compatibilizer. The polymer formula is determined by the tear fracture surface and scanning electron microscopy. The tensile properties of the blends with different formulas are studied in terms of yield strength, tensile strength, and elongation at break. Finally, three types of PBG and HDPE geocells are selected to study the long-term creep behavior using accelerated creep tests. The analysis results of raw creep data, master creep curve, and isochronous creep curves indicated that the PBG had a better creep resistance than the HDPE geocells.

Though fibres are being used in concrete structures for a couple of decades, the use of polymeric Synthetic Fibres (SyF) such as Polypropylene Fibre (PPF), Polyethylene Fibre (PEF) and Polyvinyl-alcohol Fibre (PVAF) found more rapid growth in recent years. The higher durability and physical properties of SyF increased its use in concrete despite there are some drawbacks in mechanical performances. However, the development of high modulus SyF and the use of hybrid Fibre Reinforced Concrete (FRC) systems helped to mitigate the mechanical performance drawbacks to produce superior Synthetic Fibre Reinforced Concrete (SyFRC) to use in structural elements. This paper presents the recent developments and applications of SyFRC in structural elements along with the material properties such as mechanical, fire and durability performances of SyFRC.

High-temperature thermal gradient interaction chromatography (HT-TGIC) can be used to measure the chemical composition distribution of ethylene/α-olefin copolymers using a column packed with porous...