High Density Polyethylene Composites Research Articles

The impact of chemical treatment and gamma-ray irradiation on the okra hessian cloth reinforced high-density polyethylene composites

Okra hessian cloth-reinforced high-density polyethylene (HDPE) thermoplastic composites were prepared and characterized with both raw and alkali-treated fibers. The fiber contents were optimized for both the raw Okra thermoplastic composites and the alkali-treated Okra thermoplastic composites, and the optimum value of fiber content was 55 wt%. Samples that were alkali-treated and had 55 wt% fibers were subsequently exposed to gamma radiation at doses of 2.5, 5, and 7.5 kGy. Only the sample subjected to 5 kGy showed improved performance. Treated composites exhibited higher crystallinities than the untreated samples as observed by X-Ray diffraction analysis. The rupture surface micrographs of the composites exposed to 5 kGy gamma radiation revealed more compact than others. By using Fourier transform infrared spectroscopy analysis of composites, it was found that 5 kGy dose sample showed enhanced cross-linking between Okra fibers and HDPE matrix. The irradiated composite showed less water intake than the alkali-treated samples. Composites subjected to 5 kGy gamma rays showed improved tensile strength and Young’s modulus of values 66 MPa and 1925 MPa, respectively. Compared to raw and treated composites, the irradiated composites with a radiation dose of 5 kGy showed improved structural, mechanical, and thermal properties.

Tribological performance analysis of sustainable basalt micro-filler loaded bio-based polypropylene and high density polyethylene composites

The current research work involves the fabrication and tribological properties analysis of constant basalt filler reinforced (30 wt %) bio-based polypropylene (PP) and high density polyethylene (HDPE) thermoplastic composites. Compression molding technique is used after an internal mixing process in order to produce composite samples. The physical and hardness properties have been evaluated for both neat polymers and composite samples. In order to study the coefficient of friction (COF) and specific wear rate (SWR) of PP and HDPE composite samples, the Taguchi and Analysis of Variance (ANOVA) methodologies were applied. For PP samples, the optimum parameters in response to COF are found to be 0 wt% basalt (rank 3), 9 N load (rank 1), 200 r/min speed (rank 4), and 100 m distance (rank 2); for the SWR output, the optimum parameters are 30 wt% basalt (rank 1), 6 N load (rank 4), 100 r/min speed (rank 2), and 200 m distance (rank 3). For HDPE samples, the optimum parameters in response to COF are 0 wt% basalt (rank 1), 6 N load (rank 3), 100 r/min speed (rank 4), and 100 m distance (rank 2); for the SWR output, the optimum parameters are 30 wt% basalt (rank 1), 6 N load (rank 3), 100 r/min speed (rank 4), and 150 m distance (rank 2). Consistently, it has been shown that incorporating basalt fillers to PP and HDPE composites has more dramatically decreased SWR than COF. The depth of wear constantly rises according to increasing load, irrespective of the processing variables, as shown in 2D depth profiles. It is discovered that the confirmation tests carried out for the optimum parameters are within statistically acceptable bounds. The depth profile plots revealed that the worn track edges are found with polymer bumps because of deep grooves and softened polymer debris, which commonly observed more with HDPE samples due to low softening temperature. Moreover, the worn surfaces of the composites have plowed lines and cracks that are brought about by the micro-cutting and micro-plowing activity of the erosive asperities counterface. In addition to surface characteristics, the transfer films created during sliding also significantly influenced the mode of sample wear.

A case study on the rotomolding behavior of black tea waste and bio-based high-density polyethylene composites: Do active compounds in the filler degrade during processing?

This study verified the possibility of using waste material from the food industry (black tea) as functional filler of rotomolded biobased high-density polyethylene-based composites. As part of the experimental work, the influence of the materials preparation, i.e., dry blending versus twin-screw extrusion, on the effectiveness of the stabilizing antioxidant effect of the black tea was analyzed. The aim of the work was to verify whether, despite the initial degradation of the structure of the lignocellulosic filler, it would be possible to keep its antioxidant capacity and the stabilizing effect on the polyethylene matrix. The research showed that the filler allowed to stabilize the polymeric matrix during the rotomolding process, despite the appearance of numerous defects in the form of pores and a reduction in mechanical properties, more significant for composites prepared by dry blending, obtaining elastic modulus drops of about 50 %. Furthermore, the pre-processing step by melt mixing results in a significant improvement of the composite's thermo-oxidation stability, with increases in the oxidation induction time (OIT), from 25 min for the HDPE to over 70 min for composites with 5 % black tea, and improved rheological behavior, preventing the crosslinking of the matrix, indicative of its thermo-oxidative degradation. The tea brewing process caused the decrease of antioxidant activity of the filler; however, it did not significantly affect the antioxidant behavior, maintaining its influence on the polymeric matrix when the material is prepared via twin-screw compounding, which was proved to provide better stability, increasing OIT by approximately 20 min later when compared to dry blending.

Enhanced Thermal Conductivity of High-Density Polyethylene Composites with Hybrid Fillers of Flaky and Spherical Boron Nitride Particles.

The synergistic effect between different fillers plays a crucial role in determining the performance of composites. In this work, spherical boron nitride (BN) and flaky BN are used as hybrid fillers to improve the thermal conductivity (TC) of high-density polyethylene (HDPE) composites. A series of HDPE composites were prepared by adjusting the mass ratio (1:0, 4:1, 2:1, 1:1, 1:2, 1:4, and 0:1) of spherical BN and flaky BN. The SEM results indicate that the spherical BN (with a particle size of 3 μm) effectively filled the gaps between the flaky BN (with a particle size of 30 μm), leading to the formation of more continuous heat conduction paths with the composite. Remarkably, when the mass ratio of spherical BN to flaky BN was set to 1:4 (with a total BN filling amount of 30 wt%), the TC of the composite could reach up to 1.648 Wm-1K-1, which is obviously higher than that of the composite containing a single filler, realizing the synergistic effect of the hybrid fillers. In addition, the synergistic effect of fillers also affects the thermal stability and crystallization behavior of composites. This work is of great significance for optimizing the application of hybrid BN fillers in the field of thermal management.

Molecular Dynamics Study of the Diffusion of Helium in High-Density Polyethylene Composites Reinforced with Monocrystalline and Bicrystalline Hexagonal Boron Nitride Nanosheets: Implications for Helium Storage

Molecular Dynamics Study of the Diffusion of Helium in High-Density Polyethylene Composites Reinforced with Monocrystalline and Bicrystalline Hexagonal Boron Nitride Nanosheets: Implications for Helium Storage

High-density polyethylene composites filled with micro- and nano-particles of nickel ferrite: magnetic, mechanical, and thermal properties.

With the increasing demand of new magnetic materials for modern technological application alternatives to conventional magnetic materials, the development of lightweight polymer magnetic composites has become a prominent research area. For this perspective, a new magnetic material was developed using 30 wt% nickel ferrite micro and nanoparticles as fillers for a high-density polyethylene matrix. The development process began with the synthesis of NF-micro and NF-nanoparticles using solid-state and co-precipitation techniques, respectively, followed by extrusion molding and injection molding. The success of the synthesis process and the purity of the spinel structure phase were confirmed. Additionally, using the extrusion process produced polymer magnetic composite materials with a good distribution of magnetic particles within the polymer matrix, resulting in good magnetic properties and enhanced mechanical properties of the polymer magnetic materials.

Ionizing Radiation Shielding Properties of Tantalum Pentoxide Doped High-Density Polyethylene Composites: A Theoretical Study

The rise in the utilization of radiation across various domains necessitates the advancement of next-generation radiation shielding materials that are devoid of lead. Due to their low weight and flexibility, polymer composites are considered as environmentally friendly alternative materials that can be used instead of toxic and high-weight lead for radiation shielding. From this point of view, the present study has focused on examining the radiation shielding performance of tantalum pentoxide doped high-density polyethylene (HDPE/Ta2O5) composites (including 5, 10, and 20 wt% Ta2O5) by using WinXCom software and MCNP6 simulation. The photon energies selected corresponded to the photons emitted from the Ba-133 (81 and 356 keV), Cs-137 (662 keV), and Co-60 (1173 and 1332 keV) radioactive sources that cover X-rays along with the low-and mid-energetic gamma-rays. The mass attenuation coefficient (/) of the composites has been calculated within the 81 keV-1332 keV photon range by utilizing WinXCom software and MCNP6 code. The other shielding parameters such as Half Value Layer (HVL), effective atomic number (Zeff), and effective electron density (Neff) have been determined. In the light of data, it has been revealed that gradual increase in Ta2O5 doping while improving the / coefficients, Zeff, and Neff parameters, decreasing the HVL length of HDPE considerably. Additionally, the parameters obtained by WinXCom and MCNP6 simulation are in good agreement. the. Ultimately, the best ionizing shielding performance among the composites has been determined for HDPE/20% Ta2O5 composite against 81 keV photons.

Experimental investigations on the influence of natural reinforcements on tribological performance of sustainable nanocomposites: A comparative study with polymer technology

Sustainable polymer-based nanocomposites are gaining consideration as a potential alternative to conventional composites in tribological applications. The research aimed to study the influence of reinforcements on the tribological response of sustainable polymer-based nanocomposites. In this work, nine different nanocomposites were developed by the recycling of waste plastics of three different types with incorporation of coconut fibers, jute fibers and nano-sized particles of rice husk ash. Three-body abrasive wear behaviour at five different conditions of loads and speeds were investigated. The wear of the composites increases invariably with the applied loads and speeds, and were in the ranges of 0.0154–0.2212 (cm3) and 0.02207–0.4398 (cm3), respectively. The comparative analysis of the three-body abrasive wear at the conditions of speeds has suggested the reinforcement of coconut fibers with low-density polyethylene for optimum tribological performance, whereas reinforcement of rice husk ash showed an excellent wear resistance for high-density polyethylene and polypropylene composites. The observations for three-body abrasive wear under the considered loads has suggested the incorporation of coconut fibers with low-density polyethene and polypropylene composites, whereas rice husk ash is a suitable reinforcement with high-density polyethene for optimum tribological performance. The rolling behaviour of the nanoparticles has considerably enabled the tribological performance of nanocomposites at extreme conditions of loads and speeds. The research indicated a great potential for natural reinforcement in nanocomposites and will promote the expansion of sustainable polymer-based nanocomposites for tribological applications.

The Functional and Biodegradation Characteristics of High-Density Poly-ethylene, Poly-caprolactone and Poly-ethylene Maleic Anhydride Composites

The goal of this research is to develop environmental friendly polymer composites in order to reduce the use of current polymers and promote global security. High density poly-ethylene (HDPE) and poly-caprolactone (PCL) composites were mixed with varying amounts of poly-ethylene joined maleic anhydride (PE-g-MA) as a strong compatibilizer. The different composites were prepared using the conventional infusion shaping approach. Mechanical properties were accounted for to have good increase for the diverse compositions and the strength and pliable strain% (stretching) rate at break were improved in comparison to unadulterated HDPE. Examining electron magnifying lens (SEM) morphology revealed that the expansion of PE-g-MA increased the compability and so aided in the achievement of a synergistic mix of superior qualities. The manure internment test yielded favorable bio-corruption results and demonstrated the fertilizer's ability to enable bio-debasement of various composites, allowing their utilization as key polymers in the assembly of single-use products and also protecting nature and acting as a decent waste administration of HDPE polymer.

Innovative HDPE Composites Enriched with UV Stabilizer and Diatomaceous Earth/Zinc Oxide for Enhanced Seafood Packaging and Antimicrobial Properties.

The fisheries industry encounters distinct packaging challenges, including the need to protect perishable seafood from rapid spoilage caused by UV radiation while allowing for reuse. This study tackles these issues by introducing advanced high-density polyethylene (HDPE) composites enhanced with a UV stabilizer and inorganic fillers, such as diatomaceous earth/zinc oxide (DZ). Our investigation explores the transformative effects of weathering on these pioneering composites, evaluating shifts in mechanical, physical, thermal properties, and sub-zero temperature stability. Incorporating a UV stabilizer alongside DZ within the HDPE matrix significantly enhances mechanical performance and weathering resilience. These enhancements extend the longevity of seafood packaging while preserving product quality. Moreover, our findings reveal a substantial breakthrough in antimicrobial properties. The inclusion of DZ, with or without a UV stabilizer, results in an impressive up to 99% enhancement in antibacterial activity against both Gram-positive and Gram-negative bacteria. This discovery not only bolsters the protective attributes of HDPE packaging but also presents a compelling case for the development of active packaging materials derived from DE/ZnO composites. This study bridges the gap between packaging and seafood quality, introducing advanced polymeric packaging technology for seafood products. It highlights the mutually beneficial link between packaging improvements and ensuring seafood quality, meeting industry needs while promoting sustainability.

Effect of gamma irradiation on tensile, thermal and wettability properties of waste coffee grounds reinforced HDPE composites

Abstract This study investigates the impact of gamma irradiation on the properties of waste coffee grounds (WCG)/high-density polyethylene (HDPE) composites. The composites were manufactured with 20 wt% of unirradiated and irradiated WCG at 10 and 20 kGy doses of gamma radiation. Through the utilization of a two-roll mill followed by a hydraulic press. The properties of the composites were analyzed through several methods, including contact angle measurements, hardness and tensile tests, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), in order to understand the influence of gamma irradiation. The addition of WCG decreased the tensile strength of the composite. However, gamma irradiation at 10 and 20 kGy led to substantial improvements in thermal stability and tensile strength compared to unirradiated samples. The SEM images showed the alterations within the fiber-matrix interface that corroborated the enhanced tensile properties after the treatment. While FTIR spectra confirmed the changes in functional groups of WCG caused by the irradiation process, gamma irradiation treatment not only increases fiber-matrix adhesion but also significantly improves the water resistance of the composites. These results suggest that gamma irradiation can be used for the modification of agro-waste materials as a beneficial process and the fabrication of high-performance, environmentally friendly composites.

Thermal buckling behavior of 3D printed foams: Plain, graded, and sandwich variants

The present work focuses on the experimental investigation of the thermal buckling response of 3D printed functionally graded glass micro balloon (GMB) reinforced high density polyethylene (HDPE) composites and their respective sandwiches under non-uniform heating conditions. The influences of GMB loading and its graded composition on temperature distribution are analyzed. The reinforcement of hollow GMB rendered lower thermal conductivity due to enhanced thermal resistance with an increase in filler percentage. An increased thermal buckling strength is also observed. Due to their non-uniform thermal expansion, functionally graded sandwich beams exhibited less deflection than plain beams. Among the cases of three heating conditions (One end heating: case-1, Center heating: case-2, both end heating: case-3), maximum deflection is observed in case 2 while the minimum deflection is noted in case 1. These printed foams can be utilized for lightweight thermal insulating pipes.

Enhanced strength and synergistic flame retardancy of PE-base nanocomposites with coating-modified palygorskite clay

Polyethylene (PE) - base nanocomposites composed of high density polyethylene (HDPE) as matrix and coating-modified palygorskite clay (MAT) as functional filler and fire resistance was prepared by melt blending method. The MAT powder was prepared by solution heterogeneous precipitation method combined with spray drying processes. The microstructure observation shows that the particle size of the obtained MAT powder was concentrated and even. Both mechanical properties and thermal behaviors of the nanocomposites containing MAT were compared to those with commercial ceramic fillers (naming as S type flame retardants) at the same addition mass ratios level. The added MAT mass fractions in the composite were defined as 5 wt%, 10 wt%, 15 wt%, and 20 wt%, respectively. When the addition amount of MAT is 15 wt%, the impact toughness of MAT/HDPE composites approaches 13.41 kJ/m2, which is better than that with commercial fillers. The added fractions of MAT increases to 19.1 wt%, and the elongation at break of nanocomposite reaches 495%, which is much higher than that with S type flame retardants. The differential scanning calorimeter (DSC) test results show that MAT can enhance the melting point range of HDPE and improve the thermal stability of the composite. The LOI (limiting oxygen index) results confirm that MAT can effectively improve the flame retardancy of HDPE composites, and the LOI value increases with the MAT addition. The enhancement of mechanical and thermal properties of the PE-base composite is essentially originated from the uniform dispersion of MAT in polymer matrix and the strong interactions with inorganic – organic interface compatibility.

Thermoformability study of wood flour–HDPE composites with variations in wood content under vacuum forming

Wood–plastic composites (WPCs) have emerged as sought-after substitutes for plastic. However, their use is restricted primarily to linear profiles owing to the lack of techniques for their three-dimensional (3D) forming. Thermoforming is a potential method for the 3D formation of WPCs. Accordingly, the aim of this study was to evaluate the thermoforming behaviour of extruded wood flour–high-density polyethylene composites with two different wood flour compositions (34 % and 54 %) under vacuum forming. This study examined the thermal behaviour of each structure during the forming process and the shape conformability, shape consistency, and surface quality of the formed samples. The findings suggest that increasing the quantity of plastic in composites can improve the obtained shape dimensions. Nevertheless, this improvement is accompanied by an increased level of inconsistency in the acquired profiles due to the distinct stretching rates of plastic and wood. Furthermore, the results reinforced the reliability of thermal analysis as a credible means of evaluating quality.

Electric Field Analysis of HDPE/NR Biocomposite Due to Moisture Content Condition

It is critical to develop new insulating materials that can improve the performance of next-generation high-voltage cables used in the construction of future electrical networks. The high electric field reduces solid insulation resistance and causes partial discharge through imperfections in a dielectric, causing the dielectric to age and eventually fail. Moisture is one of the most serious factors the effect the high voltage insulation status of High-Density Polyethylene (HDPE) composites. The main goal of this project is to investigate the electric field intensity of HDPE due to moisture content condition when mixed with 10g, 20g, and 30g of various bio-fillers such as coconut coir fibre, pineapple leaves fibre, and oil palm empty fruit bunch. This can be accomplished by using the Finite Element Method Magnetics (FEMM) 4.2 software to create a two-dimensional (2D) axisymmetric electrostatic model. When compared to unfilled HDPE, the inclusion of bio-filler in HDPE increased the maximum electric field intensity due to moisture content condition. The intensity of the electric field varied with the different percentages of biocomposite loading and their permittivity due to moisture content condition. The results showed, due to moisture content condition, the maximum electric field intensity was significantly lower when HDPE was added with a 10% loading of the oil palm empty fruit bunch (EFB). As a result, EFB bio-filler was the best composition because it tends to improve dielectric properties by having a lower maximum electric field intensity which is 4.214Mv/m due to moisture content condition at the top sphere electrode when compared to other compositions.

UV Radiation Effect in New Materials Developed for the Construction of Beehives.

In recent decades, there has been an increasing focus on the alarming decline in global bee populations, given their critical ecological contributions to natural pollination and biodiversity. This decline, marked by a substantial reduction in bee colonies in forested areas, has serious implications for sustainable beekeeping practices and poses a broader risk to ecological well-being. Addressing these pressing issues requires innovative solutions, one of which involves the development and fabrication of beehives crafted from composite materials that are ecologically compatible with bee biology. Importantly, these materials should also exhibit a high resistance to environmental factors, such as ultraviolet (UV) radiation, in order to maintain their mechanical integrity and longevity. To investigate this, we conducted accelerated UV degradation tests on a variety of composite materials to rapidly assess their susceptibility to UV-induced changes. High-density polyethylene (HDPE) served as the matrix material and was reinforced with natural fibers, specifically fique fibers (Furcraea bedinghausii), banana fibers, and goose feathers. Our findings indicate that UV radiation exposure results in a noticeable reduction in the tensile strength of these materials. For example, wood composites experienced a 48% decline in tensile strength over a 60-day period, a rate of deterioration notably higher than that of other tested composite materials. Conversely, HDPE composites fortified with banana fibers initially demonstrated tensile strengths exceeding 9 MPa and 10 MPa. Although these values gradually decreased over the observation period, the composites still displayed favorable stress-strain characteristics. This research underscores the substantial influence of UV radiation on the longevity and efficacy of beehive materials, which in turn affects the durability of natural wood hives exposed to these environmental factors. The resultant increased maintenance and replacement costs for beekeepers further emphasize the need for judicious material selection in beehive construction and point to the viability of the composite materials examined in this study.

Tensile Properties of Luffa Acutangula Reinforced Polymer Composite

In recent years, there has been a growing trend in the popularity of natural fiber-reinforced polymer composites (NFRPC). Numerous researchers have put forward various alternatives to synthetic fibers. Luffa is one of the many natural fibers can be integrated into NFRPCs. Luffa with its unique interconnecting branch (mat/mesh) is suitable for NFRPCs. In this study, luffa reinforced high-density polyethylene (Luffa/HDPE) composite was fabricated using compression molding machine. In the preparation of the fiber, Luffa were cylindrically cut-out and opened into sheets form. The fiber was then laminated with high-density polyethylene (HDPE) film using compression molding method. The proposed fabricated composite consisting of a fiber volume fraction (FVF) of 7%, 14%, 21%, 27% and 30%. Tensile properties of the Luffa/HDPE composite were determined. SEM was used to study the interlamination and delamination of the composite. Tensile test shows that the increase of FVF enhanced the tensile strength of Luffa/HDPE composite. Tensile strength has gradually increased from 7 % to 21 % FVF. Though, tensile strength declines after 21% FVF.

Palm oil mill effluent-derived biochar-filled high-density polyethylene composites: processability and physico-mechanical properties evaluation

Palm oil mill effluent-derived biochar-filled high-density polyethylene composites: processability and physico-mechanical properties evaluation

Friction and Wear Characteristics of Additive Manufactured CNT-Reinforced HDPE Composites in Dry Contact

The tribological properties of three-dimensional (3D) printed polymeric composites are often less explored due to the complexity involved related to their softness, poor mechanical properties, and lower thermal conductivities. Keeping this in view, this work reports the influence of carbon nanotubes (CNTs) on the tribological properties of high-density polyethylene (HDPE) composites. Fused deposition modeling was adopted to develop the composites with varying CNT contents from 0.5 wt% to 2 wt%. The tribological properties were studied by subjecting them to friction-on-wear test using a pin-on-disc setup. The tests were conducted with varying applied loads (5 to 20 N) and sliding speeds (0.262 to 1.048 m/s). A scanning electron microscope (SEM) was employed to study the morphology of the filaments and to analyze the worn surfaces after testing. The printed composite parts displayed a good dispersion of CNTs, showed a good print quality, and were free from warpage or shrinkage defects. With the increase in load and sliding velocity, both the wear rate and coefficient of friction of all the developed samples tend to increase. Out of all the developed samples, some showed poor wear resistance, while composites with the highest CNT contents of 2 wt% showed significant resistance to material loss, which is attributed to the reduced contact area and the CNT acting as an anchor to prevent the polymer chain from being detached. The worn surface analysis revealed adhesive wear as the dominant mechanism for pure HDPE, and abrasive wear as the primary mechanism for HDPE composites. Overall, this work showed that CNTs can be used as an effective filler for reducing the friction coefficient and increasing the wear resistance.

Morphology and Mechanical Properties of High Density Polyethylene and Ethylene-Methyl Acrylate Copolymer Blends with Organoclay

In this research, the effect of ethylene-methyl acrylate copolymer (EMAC or EMAC30) and clay surface modified with aminopropyltriethoxysilane 0.5-5 wt% and octadecylamine 15-35 wt% (Clay-ASO) on the morphological, mechanical, and thermal properties of high density polyethylene (HDPE) were investigated. The polymer blends and composites were prepared by an internal mixer and then samples were molded by compression molding. The morphology analysis showed that the presence of fibrous surface at the specimen fracture surface of HDPE/EMAC30 blends. The phase morphology of HDPE blends with Clay-ASO 3, 5 and 7 phr was observed the phase separation of EMAC30 and aggregate of Clay-ASO at high EMAC30 content. Young’s modulus of HDPE/Clay-ASO composites increased with increasing Clay-ASO composites. The presence of Clay-ASO did not improve Young’s modulus and tensile strength of HDPE/EMAC30/Clay-ASO composites. The strain at break of HDPE/EMAC30 blends increased with increasing EMAC30 content. The incorporation of EMAC30 and Clay-ASO had no effect on the melting temperature of HDPE blends and composites, respectively. The percent crystallinity of HDPE/EMAC30 and HDPE/EMAC30/Clay-ASO was lower than that of pure HDPE. The addition of EMAC30 and Clay-ASO decreased the degradation temperatures of HDPE/EMAC30 blends and composites.