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Background: MWCNTs tend to form agglomerates in nonpolar polymers due to their small size and large surface area. A promising approach to facilitate their dispersion within the polymeric matrix is based on employing a compatibilizer agent. Objective: The current study aimed to investigate the effect of a compatibilizer agent based on maleic anhydride grafted HDPE (PE-g-MAH) on the electrical and morphological properties of highdensity polyethylene/multi-wall carbon nanotubes nanocomposites (HDPE/MWCNT/PE-g-MAH) prepared by solution mixing and hot compaction two-step approach. Methods: A two-step approach based on solvent mixing and hot compaction was used to prepare nanocomposites of HDPE/MWCNT/PE-g-MAH with different MWCNTs and PE-g-MAH contents. The electrical, morphological, and HDPE crystalline structure properties of the nanocomposites were characterized by impedance spectroscopy, high-resolution field emission scanning electron microscopy, and X-ray diffraction, respectively. Results: The results confirm the positive role of the PE-g-MAH compatibilizer in enhancing the dispersion of the MWCNTs and, in turn, the formation of more conductive pathways at low MWCNTs content in the nanocomposites. Adding 2 wt% of the compatibilizer to the nanocomposite of 1 wt% MWCNTs increases the electrical conductivity by more than three orders of magnitude. Increasing the MWCNTs concentration by more than 1 wt% leads to a limited enhancement in conductivity of the nanocomposite prepared using 2 wt% of PE-g-MAH compatibilizer. Meanwhile, the morphological characterization revealed that the limited increase in conductivity of nanocomposites with only 1 wt% compatibilizer is related to a substantial increase in the HDPE crystallinity (from 14.8 to 43.9%) induced by the enhanced nucleating effect of the dispersed MWCNTs. The excess HDPE crystalline regions suppress the formation of effective MWCNTs conducting pathways due to their confinement into smaller inter-crystallite regions in the nanocomposite. Conclusion: Therefore, a balanced role of the compatibilizer between the dispersion of the MWCNTs and the nucleation of more HDPE crystallites has to be achieved by carefully selecting the compatibilizer type and concentration.

This present research and explores the properties of concrete's structural and durability High-density polyethylene granules (HDPE) are partly replaced by the coarse aggregate. Five separate concrete mixtures of grade M30 have been built to partially replace the coarse aggregate from 1% to 5%. The properties of strength and durability such as compressive strength, split tensile test, flexural test and durability test such as rapid chloride permeability test, acid test, alkaline test, sulphate test assault. In the acids, the samples will equate with control concrete after 190 days for durability test cubes. The experiment is conducted to evaluate how much the acid attacks on the concrete. The loads are determined by an average of 3 for the compressive strength, split tensile, flexural test.

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.

Found plastic materials, such as plastic jerrycans, make up a growing portion of contemporary African arts. West African artists, including Beninese Romuald Hazoum� and Ghanaian Serge Attukwei Clottey, are leading the way in incorporating these materials into their works, which often emulate or draw from more traditional imagery, forms, and ideas of their respective cultures. As these objects begin to enter museums and galleries, questions of their stability—intended or not—are being raised. For this research, seven different colors of jerrycans made from high-density polyethylene (HDPE), all from the manufacturer Scepter, were gathered for testing. In addition to characterization of the materials and their colorants, three primary tests were carried out: accelerated heat aging, accelerated light aging, and heat treatment where specimens were exposed to high heat and melted slightly, emulating techniques used by artists to manipulate their materials. Chemical and visual changes were tracked before, during, and after testing using photographic documentation, microscopy, Fourier-transform infrared (FTIR) spectroscopy, fiber optic reflectance spectroscopy (FORS), and color and gloss measurements. The goals of this research are to characterize the HDPE samples, investigate how these commercial materials age, and see how this compares to manipulations from the artists. Results indicate that these materials are not simply HDPE but can include additional layers such as ethylene vinyl alcohol copolymer (EVOH) as a hydrocarbon barrier, as well as stable and UV-resistant colorants. Further, these HDPE samples were resistant to heat aging, light aging, and heat treatment, with only the slightest evidence of chemical changes and almost no fading of the colorants. Aside from a few caveats discussed in the conclusion, artists may consider plastic jerrycans as a stable medium for use in art and sculpture.

Tensile strain development in high-density polyethylene (HDPE) geomembrane (GMB) liner systems in landfills was numerically investigated. A new constitutive model for municipal solid waste (MSW) that incorporates both mechanical creep and biodegradation was employed in the analyses. The MSW constitutive model is a Cam-Clay type of plasticity model and was implemented in the finite difference computer program FLAC™. The influence of the friction angle of the liner system interfaces, the biodegradation of MSW, and the MSW filling rate on tensile strains were investigated. Several design alternatives to reduce the maximum tensile strain under both short- and long-term waste settlement were evaluated. Results of the analyses indicate that landfill geometry, interface friction angles, and short- and long-term waste settlement are key factors in the development of tensile strains. The results show that long-term waste settlement can induce additional tensile strains after waste placement is complete. Using a HDPE GMB with a friction angle on its upper interface that is lower than the friction angle on the underlying interface, increasing the number of benches, and reducing the slope inclination are shown to mitigate the maximum tensile strain caused by waste placement and waste settlement.

In this study, impact of the port diameter and length changes of a solid fuel on its performance parameters was investigated to propose design considerations for the solid fuel for hydrogen peroxid...

Solvent resistant nanofiltration (SRNF) is now a powerful tool for addressing environmental issues. Hence, we report the fabrication of a thin film composite (TFC) membrane comprised of a novel HDPE support, a polydopamine (PDA)/Tannic acid-Fe(III) interlayer and a polyamide (PA) skin layer. In this respect, high density polyethylene(HDPE)-polystyrene(PS)-styrene-ethylene-butylene-styrene(SEBS) blends were formed with different compositions by mixing via a Brabender machine and making films by using a hot press instrument. Next, a solvent extraction technique was employed for extracting the dispersed phase and making the HDPE membranes. The support membrane with optimum properties was coated with a PDA interlayer. A tannic acid-Fe(III) interlayer was also formed on the as-prepared PDA layer so that the hydrophilicity of the support surface was enhanced to form a defect-free PA layer. The modified support was utilized for the fabrication of the PA top layer by using m-phenylene diamine (MPD) and trimesoyl chloride (TMC) monomers. The prepared TFC membrane provided a significant dye rejection ability (99.9% Direct Yellow, 99.7% Methyl Green, 99.2% Rhodamine B, and 96.1% Methyl Orange), extraordinary solvent resistance ability in harsh solvents, and good methanol (MeOH) Flux (2.25 L/m2.h.bar) in SRNF applications. The skin-substrate adhesion strength of the top layer was also evaluated by a back-ward flush operation. It was demonstrated that the interlayer and the skin layer had an excellent adhesion with the support membrane.

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.

The present work is to optimize the geometric parameters such as width (W), breath, total width (C), height (h), and crack length (a) of glass fiber woven mat reinforced thermoplastic laminate composite for Mode-I fracture analysis with compact tension testing mode. The laminated HDPE composites were prepared by hot compression molding with three layers of HDPE and two-layer of glass fiber woven mat. The design of experiments (L27 Orthogonal array) was prepared based on the Taguchi technique with four parameters and three levels. The mode-I fracture toughness and energy-releasing rate were calculated for all samples. The ANOVA and regression equation were used to find the effect of toughness and energy releasing rate of the laminate composites. The experimental and regression results are compared and predicted the error. Finally, the optimum shape to laminate composites is suggested for predicting fracture behaviors of various synthetic and natural fiber woven mat reinforced polymer composites in mode-I under compact tension mode.

Blending of ZnO nanostructures (e.g. nanoparticles, nanorods, moonflowers etc.) in thermoplastic matrix enables the functional composite formations. The electric conductivity, thermal conductivity, photo-catalytic properties, magnetic properties, mechanical properties, morphological properties of thermoplastic materials are some of the quantities those can modify by the blending of ZnO nanostructures. The previous studies have been reported for the reinforcement of ZnO nanostructures in polyvinylidene difluoride (PVDF), acrylonitrile butadiene styrene (ABS), high density polyethylene (HDPE), low density polyethylene (LDPE), Polyethylene terephthalate (PET), polylactic acid (PLA) etc. for different application prospective such as preparations of the bio/biomedical sensors, charge storage devices, shape memory materials, magnetic structures etc. This study is a state of the art review for exploring the functionalities and application of the ZnO nanostructures reinforced thermoplastic materials.

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.

Due to the increased socio-economic development, the manufacturing of different products based on various polymers for different applications such as space crafts, airplanes, automobiles, boats, and sports equipment are increasing continuously. This huge increase in solid polymer commodities is also creating the extravagant quantity of solid waste polymers (SWPs) due to their non-degradable characteristics. These SWPs, for example, high-density polyethylene (HDPE), polypropylene (PP), low-density polyethylene (LDPE), and nylon, etc., are used frequently in various applications and create new challenges to the industries, government, as well as end-users for systematic waste recycling/recovery in an eco-friendly manner. Moreover, in this modernisation era, almost all marble industries are also facing a huge problem as marble slurry (MS) yields a great burden not only due to its limited degradability characteristics but also wider environmental hazard towards water bodies, and rivers. Fine particles in the range size of 45-300 micron in the MS create air pollution which in turn increases breathing problems. Moreover, it also creates an ecological adverse impact on soil fertility and reduces the percolation rate of rain water which in turn reduces the recharging of groundwater. Therefore, keeping in view the above facts, the simultaneous recycling of HDPE, PP and marble slurry is adopted through single screw extrusion in order to reduce the burden on the environment. Moreover, the effect of various process parameters viz barrel temperature, screw speed (rpm), feed composition, and grain size of PP and HDPE on extrudate output was envisaged. It was found that the extrudate output increases steeply on increasing the average barrel temperature from 100 to 120°C and linearly with screw speed range from 65 to 85 rpm. The effect of grain size had shown decreasing trend in throughput whereas on increasing the polymer content in the feed, throughput was found to be enhanced. Additives such as HPMC were found to be effective when used in synergy with HDPE and PP along with MS. The extrudate throughput was found to be a maximum of 33.01 g/minute at 120°C, 85 screw rpm, 1.40-grain size underfeed with equal proportionate of HDPE/PP with 2% HPMC and 8% MS. This clearly opens the ways for proper utilization of HDPE, PP and MS waste by extrusion and provides the environmental protection solution by utilizing these polluted materials in the fabrication of value-added products through extrusion.

In this research, high-density polyethylene rods were joined together using rotary friction-welding. The effects of nanoparticle reinforcement and weld surface shape on the welded joint strength were investigated. To this aim, high-density polyethylene rods with a length of 50 mm and a diameter of 22 mm were machined, and three weld surface shapes, that is, flat, step, and conic shapes (on male and female counterparts), were created. The high-density polyethylene rods were rotary friction-welded with the addition of ZnO and SiO2 nanoparticles. The bending strength of rotary friction-welded rods was assessed by conduction of three-point bending tests. The results showed that both the weld surface shape and nanoparticles influence the bending strength of the welded joints. It was found that the step sample welds have higher bending strength (average bending depth and force of 6.27 mm and 2027.8 N, respectively). Furthermore, except for the case of flat samples, the addition of the reinforcement nanoparticles resulted in the improvement of the bending strength of the rotary friction-welded rods.

Polyethylene materials are highly important polymers which are produced in the largest volume among all plastics. Due to the chemical inert property of saturated carbon-carbon bonds, the degradation of polyethylene is extremely challenging, which prevents them from efficient chemical recycling. Installing functional groups in the main chain of polyethylenes may facilitate the degradation and following chemical recycling of polyethylene materials. Here we report a highly selective approach for the synthesis of high-density polyethylenes bearing isolated in-chain carbonyls. Linear high-molecular weight polyethylene chains are synthesized via the palladium catalyzed copolymerization of ethylene with metal carbonyls. Different from traditional ethylene/CO copolymerization reactions, excellent non-alternating selectivity has been achieved. While the properties of polyethylene have been retained in the copolymer, faster degradation compared with that of polyethylene was observed upon UV light irradiation. The synthesized materials may therefore serve as more environmentally friendly alternative plastics than traditional polyethylene materials.

The plastic waste composite molding tool with coconut fiber is designed with the aim of converting HDPE plastic waste, especially drink bottle covers mixed with coconut fiber into a product in the form of a composite board (panel) that is more useful. The dimensions of the mold are 410 x 540 mm, the tool height is 850 mm, the width is 600 mm, the length is 600 mm, the temperature of the installed heating elements is around 200-250 degrees for 12 pieces, 220 V 1000 watts, while the press uses a 10 ton hydraulic jack. While the heating temperature for pressing the composite board is set in the range of 130 – 180 oC. From the results of the first printing press with iron plate material, the resulting product is sticky on the plate surface, the second test is coated with aluminum foil, the resulting product is less than perfect because the surface is uneven. , while the third test was coated with a stainless steel plate, the resulting product was better than the previous results. This research needs to be improved in order to assist the government in handling plastic waste. In addition, the results of products with this tool will help improve people's skills and improve the economy of the products of this tool.

Separators are one of the most critically important components of lithium-ion batteries to ensure the safe performance of the battery. Commercial polyolefin separators have high thermal shrinkage and low electrolyte uptake, which confines the application of the battery. By using the thermally induced phase separation (TIPS) method, we successfully prepared HDPE/sepiolite nanocomposite separators with high thermal stability and electrolyte wettability. The sepiolite nanofibers are modified with the Vinyltriethoxysilane (VTES) as a coupling agent for better dispersion and interaction in the HDPE matrix. The purpose of fabricating this separator is to decrease the thermal shrinkage and increasing electrolyte uptake of the HDPE separator. The separator electrolyte uptake increased from 86% for pure HDPE separator to 120% for HDPE/sepiolite separator. The thermal shrinkage results indicated that the sample with 3 wt% of sepiolite after remaining for 30 min at 150 °C had only 5% shrinkage compared with 93% of pure HDPE. The results of electrochemical performance showed that the ion conductivity of the separator increased from 0.36・10–3 S・cm–1 for the pure HDPE to 0.9・10–3 S・cm–1 for the nanocomposite separator. The results of cyclability and rate performance showed that the cell assembled with a separator having 3 wt% modified sepiolite has a higher discharge capacity than the cell assembled with a pure HDPE separator.

This work is focused on the comparative study of in-situ processing temperature measurement during microwave-assisted compression molding (MACM) and conventionally compression molding (CCM) of fiber-reinforced thermoplastic matrix composite (FRTMC). In the present study, Kenaf reinforced high density polyethylene (HDPE) composite (volume fraction 20%) was chosen as the FRTMC. The processing temperature of the FRTMC was selected as per melting peak obtained from differential scanning calorimeter (DSC). The degradation temperature of FRTMC was obtained using thermogravimetric analysis (TGA). The fabrication time using MACM was found to be 84% less compared to CCM. In the MACM, temperature variation towards width and depth of specimen was found to be negligible. The thermal contours were used to observe temperature profiles during composite fabrication using CCM and MACM. Furthermore, the mechanical response of the MACM fabricated composite was better compared to CCM composite.

This paper describes non-catalytic and catalytic pyrolysis of plastic waste materials. Four types of waste plastics were used in study: high density polyethylene (PE), low density polypropylene (PP), polyethylene terephthalate (PET). Plastic waste was decomposed into three fractions under pyrolysis conditions: gas, liquid and solid residual. The use of vanadates MeVO4 and vanadites MeVO3 of REM (Me=La, Gd, Lu) as catalysts let to change the yield of the gas fraction and change the composition of the gaseous pyrolysis products. Catalytic decomposition increased the amount of the gaseous products by 15–20 %, reduced the condensate, and changed their composition with regard to the non-catalytic process at the same pyrolysis temperature. The total number of reaction products was determined in each fraction. The quantitative analysis of the composition of the gas fraction was performed by gas-liquid chromatography. The study of non-catalytic pyrolysis of plastics and thermogravimetric analysis let to determine the most favorable temperature conditions for the implementation of the catalytic pyrolysis. The catalytic pyrolysis of plastics was carried out in order to obtain the maximum yield of valuable gaseous products. The synthesized vanadites and vanadates of REM were used as catalysts. When using catalysts based on lanthanum and gadolinium compounds, a regular change in the amount of gaseous substances was observed without significant changes in their composition. The use of lutetium vanadate and lutetium vanadite demonstrated a phenomenal result that is associated with the cardinal change of structure of degradation products of PET. The syngas was obtained instead of acetaldehyde. This result is related to the structure of the used catalyst.

A catalytic reactive distillation reactor, previously described, was improved to increase the production of middle and heavy hydrocarbons, to be used as feedstock or fuel in the viewpoint of a Circular Economy of plastics. The thermal and catalytic pyrolysis experiments were run using high density polyethylene (HDPE) under several experimental conditions, with a 1 % (w/w) of HZSM-5 for catalytic pyrolysis. Three different temperatures were tested in each case and the influence of the reaction time was evaluated at 500 °C and 430 °C for thermal pyrolysis and catalytic pyrolysis, respectively. Thermal pyrolysis of HDPE produced the higher amount of solid products (80 %wt. or higher) under the form of a waxy cream-colored material (wax) for all the experimental sets. For catalytic pyrolysis, the major product fraction was always liquid. The analysis of the liquid products showed that, for both thermal and catalytic pyrolysis, the products obtained were within the range of C5 to C11, with a higher yield on C8 and C9 in the case of thermal pyrolysis and on C6 and C7 for catalytic pyrolysis. The aim of this study was the development of an integrated reactor/separation system to increase the middle olefin production. It is possible with this reactor design to direct the pyrolysis of HDPE to the production of middle olefins that can be reused in the petrochemistry industry, as chemical feedstock, including in the production of new plastics.

The recycled low density polyethylene (LDPE), recycled high density polyethylene (HDPE) and recycled polyethylene terephthalate G copolyester (PETG) as post-processed plastic wastes from extrusion blow molding process were modified with blending process to improve the properties of those plastic wastes and decrease the amount of plastic wastes in the plastic processing plants. The recycled PETG was blended with recycled LDPE and recycled HDPE in various concentration from 0 wt% to 100 wt% in increments of 10 wt% as referred to LDPE/PETG blends and HDPE/PETG blends respectively prepared by co-twin screw extruder. The addition of PETG in the blending of LDPE and HDPE improved the mechanical properties and MFI of those polymer blends but decreased thermal stability, storage modulus, loss modulus and complex viscosity as compared to those of neat LDPE and neat HDPE. LDPE/PETG blends illustrated better impact properties and flexibility than those of HDPE/PETG blends.

Recycling of plastic materials has become more environmentally important than recycling of other materials. The most important problem during recycling is the presence of oil, dirt, dust and metal particles that are mixed with plastic materials. These mixtures can change their its mechanical and physical properties and it is quite costly to remove them completely. Removing iron alloy particles from plastic is possible by using the magnetic method. However, removing non-metallic materials requires extra processing. In this study, the use of recycled High-Density Polyethylene (rHDPE) without an expensive cleaning processes has been investigated. Different amounts of aluminium oxide (Al2O3) were added to High Density Polyethylene (HDPE) to simulate the effect of non-metallic material involved. The effect of these contamination rates on the mechanical and physical properties of HDPE was examined in detail. For this purpose, recyclable materials were produced by mixing rHDPE with 1%, to 7% Al2O3 . The results show that up to 7% of the mixture has acceptable effects on the properties of HDPE. When the results of the experiments are examined, it is observed that there is a 3.74% change in the elastic modulus of the material. This means, that up to 7% non-metal contaminated rHDPE material can be used without any costly recycling process.

The plastic waste has suffered a dramatic increase and has become one of the biggest environmental problems nowadays. The chemical transformation of plastics by catalytic cracking under hydrogen atmosphere (hydrocracking) is one of the viable solutions to this problem since it can convert plastic residues into petrochemicals and fuels. In this work a thermogravimetric study of high-density polyethylene (HDPE) conversion under hydrogen atmosphere and in the presence of catalysts with different textural and chemical features is presented. The effect of distinct micro (H-ZSM-5, H-FER and H-MOR) and mesoporous (SBA-15 and MCM-41) catalysts is studied, both in terms of energy requirements and products distribution. Moreover, the effects of sample preparation method, catalyst amount, Si/Al ratio and incorporation of a metallic function (Ni and Pt) are also analyzed. The results show that when MCM-41 and SBA-15 mesoporous silicas are added to HDPE no significant changes are observed in terms of the degradation profile. On the contrary, the use of microporous materials decreases significantly the onset of HDPE degradation temperature. The accessibility and acidic content of the materials proved to be the most important factors influencing the HDPE degradation profiles. Moreover, the introduction of a metal function results in a further shift to lower degradation temperatures and favors the liquid products distribution, promoting the formation of gasoline and diesel.

Sustainability metrics have been established that cover the economic, social, and environmental aspects of human activities. Reduce, reuse, and recycle (3R) strategy targets solid waste management in the waste generation sectors. The purpose of this work is to study the possibility of using various plastic wastes containing high-density polyethylene (HDPE) and high-density polyethylene nanoclay (PMON) as polymer additives to modify lubricating oil. The structure of these additives was elucidated by Fourier transform infrared (FTIR) spectra, and the particle size of PMON was determined by dynamic light scattering (DLS). The thermal stability of HDPE and nanoclay HDPE (PMON) was studied, which showed higher thermal stability, and these additives completed degradation above 500 °C. The performance of HDPE and nanoclay HDPE (PMON) in lubricating oil was evaluated as pour point depressants by standard ASTM methods. The results showed that the efficiency of these additives increases with the decrease in the dose of these additives and lubricating oil treated with HDPE at 0.25% dosage lowers PPT to -30 °C, while lubricating oil treated with nanoclay HDPE (PMON7) at 0.25% dosage reduces PPT to -36 °C. Photomicrographic analysis was conducted to study accumulations and modifications in the wax crystal morphology in lube oil without and with HDPE and nanoclay HDPE (PMON7). Photomicrographs revealed that wax morphology changes due to effective pour point depressants on crystal growth.

Bu çalışmanın amacı termoplastik kompozitlerde atık çay odunu liflerinin kullanımı ve maleik anhidritle muamele edilmiş polietilenin etkisini araştırmaktır. Bu amaç doğrultusunda, matris olarak yüksek yoğunluklu polietilen (HDPE), lignoselülozik dolgu maddesi olarak atık çay odunu lifleri (WTWF) ve uyumlaştırıcı olarak da maleik anhidritle muamele edilmiş polietilen (MAPE) kullanılmıştır. Enjeksiyon kalıplama yöntemiyle %0-15-30 oranlarında WTWF dolgu maddesi ile MAPE’li ve MAPE’siz olmak üzere altı faklı kompozit üretilmiştir. Kompozit malzemelerin fiziksel, mekanik, termal ve morfolojik özellikleri belirlenmiştir. Sonuç olarak, termoplastik matriste WTWF oranını artması ile kompozitlerin çekme direnci, çekmede elastikiyet modülü, eğime direnci ve eğilmede elastikiyet modülü değerleri yükselmiştir. Fakat termoplastik matriste WTWF’in artması kompozitlerin kopmada uzama ve darbe direnci değerlerini azaltmıştır. Termoplastik matrise MAPE’nin eklenmesi ile kompozitlerin çekme direnci, eğilme direnci ve eğilmede elastikiyet modülü değerleri yükselmiştir. Termal özelliklere bakıldığında termoplastik matrise WTWF eklenmesi ile kompozitlerin kömür oranı artmıştır. Fakat başlangıç bozunma derecesi değişmemiştir. Atık çay odunu liflerinin HDPE bazlı termoplastik kompozitlerde dolgu maddesi olarak potansiyel bir kullanıma sahip olabileceği görülmektedir., The objective of this study was to investigate the utilization of waste tea wood fibers (WTWF) and effect of maleic anhydride treated polyethylene (MAPE) in thermoplastic composites. For this purpose, HDPE as matrix, WTWF as lignocellulosic filler and MAPE as coupling agent were used. Six different composites were produced by injection molding method; 0-15-30% WTWF filler ratio, with MAPE and without MAPE. The physical, mechanical, thermal and morphological properties of composite materials were determined. As a result, tensile strength, tensile modulus, flexural strength and flexural modulus of the composites were increased with the rise of the WTWF amount in the thermoplastic matrix. However, WTWF increase in the thermoplastic matrix reduced the elongation at break and impact strength of the produced composites. Addition of MAPE in thermoplastic matrix improved tensile strength, flexural strength and flexural modulus of manufactured composites. In the case of thermal properties, addition of WTWF into the thermoplastic matrix increased the char rate of the composites. However, the initial degradation did not change. It appears that waste tea wood fibers may have a potential usage as filler in the HDPE-based thermoplastic composites.

Polymer waste volumes have surged in recent years as a result of growing industrialization and fast improvements in living standards. In Malaysia, the majority of polymer waste is discarded rather than recycled. This circumstance results in major issues such as waste of natural resources and pollution of the environment. Polymer products, such as synthetic fibres, plastics, and rubber, are petrochemical compounds that disintegrate slowly in nature. Even after a long amount of time, plastic materials are not easily biodegradable. In reality, a wide range of waste materials can be used as a cement matrix inert. For the manufacture of the polymer concrete, trash bag plastics were employed as polymer wastes HDPE in this study (PC). The purpose of this research is to investigate the characteristics and characterisation of polymer HDPE as a coarse aggregate replacement in concrete. Temperatures of 160°C, 170°C, 180°C, 190°C, and 200°C were used in the heating procedure. By volumetric approach, five compositions of coarse aggregate with varied crushed stone: HDPE waste ratios of 0:100, 15:85, 30:70, 45:55, and 60:40 were utilised. The use of polymerwaste as coarse aggregate in traditional concrete was examined. With fresh and hardened concrete tests, the effects of polymer wastes on the workability and strength of the concrete were investigated. After 28 days, the compressive strength of the PCwas determined to be suitable for nonstructural use. The findings of the cost research revealed that the PC is more cost effective than traditional concrete. Keywords: Polymer Wastes HDPE; Coarse Aggregate; Compressive Strength; Properties

The study of the behavior of polymeric material used for insulators in the electrical system is extremely important in order to evaluate their lifetime as well as their performance when exposed to different environmental conditions. In the present work, the behavior of high-density polyethylene (HDPE) pin type insulators (15 kV), under accelerated aging conditions, was studied. Samples were exposed to aging, for 200 h, 1000 h, and 2000 h, in accelerated weathering chambers, according to two different methods. In Method 1, the parameters were established based on natural aging in location conditions, and in Method 2, ASTM G155 standard parameters were used. All samples were characterized by rheometry, Fourier-transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The accelerated aging conditions, used in Methods 1 and 2, affected the aging of HDPE pin type insulators samples differently, the changes being more intense in Method 1.

In this paper, multiwall carbon nanotube-ZnO (MWCNT/ZnO) was melt-blended with polyethylene (PE) by a Haake-Buchler Rheomixer. The mechanical properties, thermal stability and dispersion degree of the composite materials was characterized. Differential scanning calorimetry, X-ray diffraction analysis, thermogravimetry, tensile test and SEM were carried out. The results showed that with the addition of MWCNT/ZnO, the crystallinity and thermal degradation temperature of PE changed. 0.2phr MWCNT/ZnO/PE exhibited crystallinity that was 10% higher than PE. With the addition of MWCNT/ZnO, the tensile strength of PE decreased gradually, but the elongation at break increased first and then decreased. When MWCNT/ZnO content is 0.2phr, the elongation at break of the composite is close to 532.21%, which is 116% higher than that of pure PE.

High-density polyethylene (HDPE) is used as the matrix and attapulgite (ATT) is used as the reinforcing phase. HDPE/ATT nanocomposites are prepared by melt blending. The effect of ATT content on the mechanical properties, water absorption and morphology of HDPE/ATT composites was studied. The results show that adding a small amount of ATT can improve the mechanical properties of HDPE, but excessive addition will reduce the mechanical properties of HDPE. The water absorption and contact angle test results show that as the ATT content increases, the composite material becomes more and more hydrophilic. After joining ATT, the performance of HDPE / ATT composite material has a significant improvement effect, and it is believed that it will have broad application prospects in the future.

Enormous amounts of plastic wastes are generated worldwide and the approaches related to plastic recycling or reusing have become the research focus in the field of composite materials. In this study, green composites were prepared via melt-blending method using high-density polyethylene (HDPE) sourced from plastic bags as a matrix and sugarcane bagasse (SCB) fiber as reinforcing filler. The effects of fiber loading (5, 10 and 15 wt%) and fiber modification on the mechanical and dimensional stability (weight gain by water absorption) properties of the green composites were investigated. Results showed that the inclusion of SCB fiber into recycled HDPE matrix increased the composite stiffness but decreased the mechanical strength and resistance to water absorption. With the fiber modification through alkali treatment, the mechanical strength was remarkably improved, and the modulus and water absorption of the composites were found to be reduced. From the finding, it can be concluded that the prepared green composites free of coupling agent could add value to the plastic and agricultural wastes, and serve a potential candidate to replace some conventional petroleum-based composites.

Low- and high-density polyethylene (LDPE/HDPE) have been selectively depolymerized, without added H2, to C2–C20 + alkanes/alkenes via energy-efficient radio frequency induction heating, coupled with dual-functional heterogeneous Fe3O4 and Ni- or Pt-based catalysts. Fe3O4 was used to locally generate heat when exposed to magnetic fields. Initial results indicate that zeolite-based Ni catalysts are more selective to light olefins, while Ni supported on ceria catalysts are more selective to C7–C14 alkanes/alkenes. LDPE conversions up to 94% were obtained with minimal aromatic, coke, or methane formation which are typically observed with thermal heating. Two depolymerization mechanisms, a reverse Cossee–Arlman mechanism or a random cleavage process, were proposed to account for the different selectivities. The depolymerization process was also tested on commercial LDPE (grocery bags), polystyrene, and virgin HDPE using the Ni on Fe3O4 catalyst, with the LDPE resulting in similar product conversion (∼48%) and selectivity as for virgin LDPE.

High-density polyethylene (HDPE) pipes have become the preferred water pipes in nuclear power plants. Since the butt fusion–welded joint of HDPE pipes is a weak link of a piping system, it is essential to study the creep properties of the welded joint. In this study, the creep properties of the welded joint of HDPE pipes were studied using a nanoindentation creep test. The test results showed that the weakest creep resistance was not located in the weld center, but was a little away from the weld center. The power-law creep constitutive model was constructed at different locations of the welded joint based on the test results. In addition, the hardness of the welded joint was tested. The results showed that the hardness of the welded joint could reflect the creep resistance of the welded joint.

In this work, a natural fiber obtained from a water hyacinth (WH) plant was used as reinforcement in high-density polyethylene (HDPE) for the fabrication of WH/HDPE composite by the compression molding process. Fabrication parameters such as water hyacinth content, alkali treatment concentration, treatment time, and coupling agent amount were varied in three levels, and composites specimens were fabricated according to Taguchi’s L9 orthogonal array. Grey Relation Analysis was used to optimize the fabrication parameters. The results showed that the increase in WH fiber volume fraction, NaOH concentrations, and treatment time increased the tensile and flexural strength of the composite up to some point and after that, it decreased. However, the strength of the composite was found to decrease with the increase in NaOH concentration and decrease in coupling agent concentration. It was revealed that the water hyacinth particle content had the highest contribution to tensile and flexural strength, followed by coupling agent dosage, treatment time, and NaOH concentration in order. Mechanical properties were optimized when the WH/HDPE composite was fabricated with 30% water hyacinth fiber, treated with 5wt% NaOH concentration for 12 h, and mixed with a 15% coupling agent. The fabricated WH/HDP composite can be used as a viable alternative material for making furniture, ceiling, tile, and partition boards.

In this study, the effects of filler amounts were studied on the mechanical and thermal properties of high-density polyethylene (HDPE), polystyrene (PS) and polyoxymethylene (POM) polymers reinforced with short rape fibers. HDPE-rape, POM-rape and PS-rape fiber composite materials were prepared with different fiber contents and their tensile, flexural, Izod impact and TGA/DTA properties were examined. When tensile and Izod impact properties were compared, it was observed that an increase in the amount of filling in HDPE-based composites did not cause any significant changes in these peoperties, while they were decreased for POM- and PS-based composites. On the contrary to tensile and impact strengths, when the three-point flexural properties were examined, it was observed that the strength values of all these materials increased with increasing the amount of fillers. However, a pronounced increase was observed in the three-point flexural strength of the HDPE-based composite materials. The flexural strength of 30 wt% rape-reinforced HDPE composite was found to be twice that of the pure HDPE. The results of TGA and DTA analyses revealed that the reinforcement element started to burn before the matrix material and therefore burning was delayed in these thermoplastics. As a result, the mechanical properties of HDPE composite materials improved with rape reinforcement. In this way, by using approximately 30 wt% natural filling material in a polymeric matrix, an environmentally friendly material, as well as, significant advantages in cost can be obtained.

The recycling of high-density polyethylene plastic (HDPE) plays a crucial role in sustainable development. However, obstacles to the use of recycled HDPE remain because of the material and processing properties and odors of recycled HDPE. The odor of recycled detergent bottle plastic leads to rejection by most detergent manufacturers. Recently, some recycling enterprises have adapted recycling with odor reduction processes involving the use of solvents, antimicrobial additives, and odor extraction units in feeders and extruders. However, these processes may affect the quality and cost of recycled plastic. Most small and medium businesses (SMBs) may not favor these effects due to their limited models and resources. In addition, most SMBs are unwilling to replace their current recycling operation units. Hence, this study aimed to find alternative and economical ways for odor reduction in the recycling process. A modification of the recycling process was introduced in the pretreatment of plastic flakes before entry into the feeder of an extrusion unit. The effect of selected washing temperatures, i.e., 65℃, 75℃, 85℃, and 95℃, on the removal of odor from recycled HDPE was further studied. The addition of sodium bicarbonate, calcium carbonate, and citric acid into a heated water bath enhanced the deodorizing effect. The relationship of these three chemicals with the deodorization of HDPE plastics was investigated through sensory evaluation. Lastly, the potential of the deodorized recycled HDPE for resin pellet production and commercialization were investigated.

In this study, the composite materials based on high density polyethylene (HDPE) and yellow phosphorus slag (YPS, by-product of yellow phosphorus production) were prepared using melt blending metho...

In-situ synthesis of high-density polyethylene (HDPE) reinforced groundnut shell particulate (GSP) composite with treated GSP within the range of 10-30 wt% at 10 wt% has been achieved. The adopted technique used in the production of the composite is melt mixing and compounding using two roll mills with a compression moulding machine. Properties such as hardness, tensile strength, impact energy and water absorption analysis were examined. The result revealed that addition of GSP increases the hardness value from 22.3 to 87 Hv. However, the tensile strength progressively decreased as the GSP increases in the HDPE. This trend arises due to the interaction between neighbouring reinforced particulate which appears to influence the matrix flow, thereby inducing embrittlement of the polymer matrix. It was also observed that water absorption rate steadily increased with an increase in the exposure time and the absorbed amount of water increases by increasing the wt% of the GSP. Analysing the obtained results, it was concluded that there were improvements in the hardness, tensile strength, impact energy and water absorption properties of the HDPE-GSP polymer composite when compared to unreinforced HDPE. On these premises, GSP was found as a promising reinforcement which can positively influence the HDPE properties of modern composites.

This paper presents the results of an investigation of the influence of the aluminum-powder concentration on the thermomechanical characteristics of the composites based on the high-density polyethylene. We show that use of a compatibilizer—maleic anhydride–polyethylene graft copolymer—in a mixture with high-density polyethylene has an influence on the regularity of variation of the thermomechanical curves. We study the influence of various cross-linking agents (dicumyl peroxide and sulfur) on the thermomechanical properties of composites. At a particular dicumyl peroxide and sulfur concentration, the composites might reside in three physical states: solid, highly elastic, and viscous flow.

The annual worldwide production of coffee exceeds 10 million tons, and more than 90% of this production is waste, including the husk. On the other hand, plastic consumption increases every year, and sustainable alternatives are necessary to decrease it. This work arises to solve these two problems, and seeks to produce products at an industrial level from polyethylene/coffee husk eco-composites. Both Low Density Polyethylene and High Density Polyethylene were used, and the amounts of coffee husk added as filler were 20 and 40 wt%. The composites were characterized by different morphological, thermal and mechanical techniques. Scanning Electron Microscopy images showed husk particles embedded in the polymer matrix, but with some gaps between the polymer and the filler, because no compatibilizer agent was used. The addition of large amounts of natural filler negatively affected the tensile strength and elongation at break, but increases eco-composites crystallinity, and hence, their Young modulus and hardness. The industrial applicability of the eco-composites was verified through the production of five different consumer products by extrusion and injection processes, using mixtures with 40 wt% coffee husks. All products were obtained without significant defects. If only 3.25 wt% of the polyethylene products produced each year in Colombia did so with the eco-composites developed in this work, all the coffee husk produced in the country would be used, and the emission of about 5.390 million m3 of greenhouse gases would be avoided.

Polypropylene/epoxy/synthetic graphite (PP/EP/SG) and high-density polyethylene (HDPE/EP/SG) composites were prepared by melt mixing followed by compression molding. The immiscibility of the polyolefins with epoxy was confirmed by thermogravimetric analysis. Scanning electron microscopy (SEM) studies showed that HDPE/EP blend exhibits inferior interfacial adhesion between the component polymers compared to PP/EP blend. Also, the effect of SG content on flexural properties, density, moldability, water absorption, and porosity of the PP/EP/SG and HDPE/EP/SG composites was investigated. For both PP/EP/SG and HDPE/EP/SG composites, flexural modulus, density, and porosity increased with increase in SG content. For PP/EP/SG composites, the water absorption decreased from 0.154% at 30 wt% SG to 0.072% at 70 wt% SG. Further increase in SG content to 80 wt% caused an increase in water absorption. On the other hand, water absorption for HDPE/EP/SG increased with SG content all through. At the same filler loadings, PP/EP/SG composites showed lower density and porosity and performed better in terms of flexural modulus and water absorption compared to HDPE/EP/SG composites.