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The use of plastic has been increasing in various aspects of modern life, leading to a huge amount of plastic waste, which affects negatively the environment and humanity. In this paper, the effect of high density polyethylene (HDPE) and low density polyethylene (LDPE) wastes as a partial replacement of natural sand is studied and examined some mechanical properties of concrete. All specimens (60 specimens) were tested after 7 and 28 days. Concrete mixes containing minced polyethylene were prepared by using the replacement ratios partially (5, 10, 15, and 20) by volume of sand. The test results showed that the density of HDPE and LDPE decreased with the increased amount of polyethylene ratios. The values of compressive and splitting tensile strengths for the specimens containing HDPE were higher than the strengths of specimens containing LPED. The results also showed the specimens with 5% and 20% replacement ratios an increase in the strengths, while the specimens with 10% and 15% replacement ratios showed varying behavior of the strengths. [ABSTRACT FROM AUTHOR]

Degradation of isotactic polypropylene (PP) and high-density polyethylene (PE) occurs in an accelerated way during melt processing. Hence a study of the thermo-oxidative and thermomechanical stability was performed on a corotating twin-screw extruder. First, the origin and effects of degradation were studied. The effect of shear stresses and residence time during compounding on the chemical composition, rheological behavior and mechanical performance was examined. Next, the thermomechanical stability of PP was enhanced by adding HDPE to the PP matrix. Small amplitude oscillatory shear measurements indicated a significant decrease of PP's viscosity (-40%) after 1 compounding cycle. This was in contrast to PE where no change in viscosity was observed. The viscosity loss was more pronounced in the terminal regime, indicating a higher impact on the long chain molecules due to β-scission reactions. Fourier transform infrared measurements did not show any presence of secondary oxidation products. Thus, thermo-shear was expected to play a dominant role in PP's degradation mechanisms. The addition of a relatively small amount PE (<20 wt%) to the PP matrix could enhance thermo-shear stability without decreasing mechanical performance. Adding 10 wt% HDPE to PP recovered almost completely the viscosity loss caused by the extrusion processing. However, PE and PP remain two separated phases. Due to low interfacial tension and well-dispersed uniform particle size, no negative influence was observed in the mechanical properties. These results provide important insights into the thermo-shear stability of PP and PE during melt processing. Furthermore, the addition of a relatively small amount of PE to the PP matrix can counteract the thermo-mechanical degradation mechanisms that affect the properties of PP. In the end, these findings can create more opportunities to use PP recyclates in different types of applications. [ABSTRACT FROM AUTHOR]

Guardrails are common and important elements of the road safety system. Among the semi-rigid roadside barriers, steel w-beam guardrails are dominating, despite being susceptible to corrosion and incurring relatively high costs of maintenance. As an alternative, fiber-reinforced polymer materials, possessing such advantages as resistance to corrosion and fatigue, elastic deformation capacity, and low density, are being considered. Both thermoset and thermoplastic matrix composites have been studied for roadside restraint applications, the latter having the advantage of more ductile deformation response. Replacing the steel with a thermoplastic polymer composite as the guardrail material is likely to bring economic, environmental (e.g. the utilization of recycled plastic), and functional benefits. The aim of the present study was developing of an efficient production technology of E-glass fiber/low density polyethylene (LDPE) guardrail. A laboratory-scale rolling and thermoforming line has been developed allowing continuous feeding of LDPE sheets with glass-fiber yarn reinforcement located between them. In the rolling machine, LDPE sheets are subjected to a short-term heating by hot air blowers causing partial melting of the sheets and penetration of the polymer into the yarns. The in-plane mechanical properties of the composite produced were characterized by tensile and compressive tests along the reinforcement direction, transverse tensile tests, and compact tension tests. Quasi-static validation tests of prototype guardrail elements have been performed to reveal their load-bearing capacity. [ABSTRACT FROM AUTHOR]

Currently, an organic filler like RH (RH) is widely used in polymer matrix composite (in the filler such as light weight, low cost and environmentally friendly. However, the compatibility of the materials is low due to poor interfacial adhesion of matrix which is low density polyethylene (LDPE) and fibre. To overcome this issue, heat treatment on RH as an alternative to replacing chemical modification of chemical treatment has been used. Heat treatment on the fibre will eliminate the vulnerable components in RH structure and further increase the thermal stability of RH. This project focus on the effect of different filler loading of RH on the mechanical properties and morphology studies of polymer matrix composites (PMC). Two different fillers loading where 10wt% and 20wt% were used using twin screw extruder for compounding of matrix and fibre with addition of maleic anhydride polyethylene (MAPE) as compatibilizer. RH were undergoing heat treatment at three different temperatures which are 180°C, 200°C and 220°C before compounding process. Then, extruded composites were injected using injection molding machine to obtain dumbbell and rectangular shapes for tensile and flexural testing. From the testing, results showed that the properties of tensile and flexural were improved PMC due to variety of benefits contained with increasing of fibre loading. Furthermore, results obtained showed that heat treatment on 20wt% of RH at temperature 180°C exhibited better mechanical properties and interfacial bonding compared to oter compositions. Fourier-transform infrared spectroscopy (FTIR) was applied to determine the functional group of heat treated and untreated composites. In term of application, this composites could fit in packaging product like eco-friendly food packaging and biodegradable straw. [ABSTRACT FROM AUTHOR]

Linear Low-Density Polyethylene (LLDPE) has good mechanical properties, translucent, flexible, waterproof, and easily processed into thin sheets. Therefore, LLDPE is suitable for mulch film production. However, besides having advantages, LLDPE-based mulch film has some disadvantages when applied in the field. LLDPE mulch is easily degraded due to sunlight ultraviolet (UV) radiation and is also difficult to decompose in the soil after it's used. The addition of lignin or coconut coir powder that has high lignin content was intended to improve LLDPE mulch properties regarding UV resistance properties and biodegradability. In this preliminary study, the mechanical and thermal properties ofLLDPE mulch by adding lignin and coconut coir powder with high lignin content were studied. The mulch was in form of a thin sheet plastic composite. LLDPE and lignin or coconut coir powder were compounded with rheomixer at a temperature of 120 °C, and a rotor speed of 80 rpm for 6 minutes. The proportion of lignin or coconut coir powder was 1%, 5%, and 9% of the total weight. Thereafter, the compound produced was hot-pressed into a thin sheet of plastic. The plastic sheet's mechanical properties were characterized using Universal Testing Machine and the thermal properties were analyzed using Differential Scanning Calorimeter. The addition of 9% coconut coir powder resulted in the highest modulus of elasticity and tensile strength values, which were 0.202 GPa and 16.91 MPa, respectively. Thermal analysis of LLDPE with the addition of lignin showed melting points that were close to LLDPE or lignin. The addition oflignin slightly changed the LLDPE melting point. The crystallization temperature (Tc) of LLl (lignin 1%), LLS (lignin 5%), and LL9 (lignin 9%) were not much different; 106.22°C, 106.22°C, and 105.66°C, respectively. The addition of 5% lignin or coir powder increases the crystallinity of LLDE film compared to the addition of 1% lignin or coir powder. However, the addition of9% lignin or 9% coir powder decreases the mulch film's crystallinity, due to higher lignin or coir powder content loading into LLDPE which prevents the crystallization of LLDPE. Based on thermogravimetry analysis, LLDPE+lignin 9% film is more thermally stable than LLDPE+coir 9% film. Moreover, the temperature processing of coir powder while blended with thermoplastic should be below 209°C to avoid thermal degradation of the coir powder. [ABSTRACT FROM AUTHOR]

The purpose of this work was to investigate the effect of nickel-impregnated niobium oxide catalysts in the catalytic reforming of pyrolysis oils produced from low density polyethylene (LDPE) waste plastics. Wet impregnation was used to synthesize nickel-impregnated niobium oxide catalysts with varying amounts of Ni metal loading. SEM-EDS, XRD, and FT-IR were used to gain a better understanding of the catalyst characteristics such as crystallinity, surface topography, and functional groups. The LDPE pyrolysis oils were catalytically reformed in a fixed-tubular reactor with 2 mL/h flowrate of feed by using 0.5 g NiO/Nb2O5 catalysts at 450 °C with different loading of nickel onto catalysts (2%, 4%, 6%, 8%, and 10%wt), and N2 (99.9%) as the carrier gas. The highest yield of the improving oils from LDPE was reached by 67.33%. The products of the catalytic reforming process in terms of the chemical compounds were investigated by using GC-MS analysis. The GC-MS analysis shows that the improved oils mostly comprise aliphatic (straight, branched-chain of paraffin and olefin) and aromatic compounds. The carbon number of improved oils is mostly in the C6-C26 range, with the high hydrocarbon content of the gasoline at 76.46% (C5-C12). The characterization of improved oils, including viscosity, density, and calorific value, was examined to confirm the purpose of catalyst function and that it was within the fuel standard. The results confirm that the NiO/Nb2O5 catalyst has good performance in the catalytic reforming process of pyrolysis oil derived from LDPE waste plastics. [ABSTRACT FROM AUTHOR]

In the past one-decade 3D printing has been widely explored for the fabrication of energy storage devices (ESD) like batteries, capacitors, etc. Some studies have been reported on the use of polyvinylidene fluoride (PVDF) composite for smart battery applications through the melt processing route. But hitherto little has been reported on the charge capacity of PVDF composite matrix reinforced with low-density polyethylene (LDPE) and different chemicals/salts namely graphite, ZnCl2, and NH4Cl. This study highlights the charge capacity in terms of resistance offered by the 60%PVDF+40% LDPE (X) matrix reinforced with graphite, ZnCl2, and NH4Cl(in different weight proportions using melt processing route). The composite filaments were extruded using a twin-screw extruder (TSE) by considering the (screw temperature (T), screw speed (S), and load (L) on screws) as the input parameters. The results of the study suggest that 50% graphite, 50% ZnCl2, and 30% NH4Cl is suitable for minimizing the resistance and getting the best charge flow. Further, the results of mechanical, and morphological properties for different PVDF composites have been supported by scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). [ABSTRACT FROM AUTHOR]

These accumulations of used plastics like high-density polyethylene (HDPE) and low-density polyethylene (LDPE) cause environmental pollution in various way. Biological treating method can be an alternative of solution for reducing the accumulation of plastics in our environment. In this study, Plastic samples were pre-treated by placing under exposure of ultraviolet (320±10 nm) for 5 days continuously. Then, placed in the microalgae Anabaena sp. culture and Chlorococcum sp. culture for biological treatment for 21 days. FTIR and SEM been used and observed the functional group changes and surface changes on polyethylene. From the biological treatment between treated polyethylene and microalgae found that both microalgae shown well grown. In LDPE found greater growth of Chlorococcum sp. higher than Anabaena sp. HDPE does not shown any obvious changes in growth of microalgae. FTIR result shown the changes in mechanical structure of LDPE by reduction of ester groups -(C-C-O-C-C)- after biological treated with Chlorococcum sp. Visual changes as pattern of round rupture circle found on the surface of LDPE as compared HDPE which analyzed though FESEM result. [ABSTRACT FROM AUTHOR]

The paper evaluates SI engine performance in various blended fuels by adding up to 30% of plastic pyrolysis oil (PPO) from low-density polyethylene (LDPE). The production of PPO was referred to that carried out by another researcher. The investigation was realized by using a single-cylinder engine test-bed with a speed ranging from 1000-4000 rpm. As a baseline, the first experiment applied pure gasoline to have the brake torque (BT) and brake specific fuel consumption (BSFC) at various engine speeds. The next step is pure gasoline was blended with PPO by adding 10% and 30%, the result in a new mixture of fuel called PPO10 and PPO30, respectively. At the same procedure, using both of them was carefully investigated to advance analysis. Performance testing of the SI engine showed that the maximum of brake torque PPO10 type is lower by 1.7% (1.011 Nm at 2722 rpm), and the PPO30 lower by 7.3% (0.953 Nm at 2722 rpm) when compared to gasoline fuel at 1.029 Nm at 2722 rpm. Maximum brake power is 0.286 kW at 2722 rpm for the use of PPO10, and PPO30 is 0.27 kW at 2722, where this value is 3.3% and 8.6% lower than gasoline (0.296 kW at 2722 rpm). Other results showed that using both blended fuels is more efficient in fuel consumption than gasoline. [ABSTRACT FROM AUTHOR]

Today's Environmental condition attracts every researcher to address the issues causing problems in it. One such issue is waste plastics in solid waste disposal, due to its non-degradable nature and long shelf life. Replacement for these plastics is quite difficult in the era in which everything depends on it due to its unique properties. Instead of avoiding it, one must work towards its proper utilization and finding solution for the already produced "one time use" plastics. Many works has been carried out to solve waste plastic reduction from disposal such as Methanolysis, Hydrolysis, Glycolysis, Gasification and Pyrolysis. Among these except pyrolysis all other process need homogeneous and complex condition for operation. Pyrolysis gaining importance as it is converting waste plastics into value added product like, light oil, gasoline and fuel grade hydrocarbon by heating the plastics in absence of air in defined condition. These hydrocarbon obtained can be directly used in energy sector as alternative fuel to meet the requirement. To improve the quality and quantity of yield obtained by pyrolysis process, many catalysts were used. Some of them are acid catalysts, HZSM-5, HY and Hb-zeolite-based catalysts, the solid super acid catalysts ZrO2/SO4, and Pt-stabilized ZrO2/SO4, ECat-1, Aluminum oxide γ-Al2O3. These catalysts reduce the problem associated with thermal pyrolysis like high temperature and high reaction time but are difficult to maintain due to large amount of carbon deposition andis economically not feasible to use in industrial scale. Current work is focusing on using alumina-silicates composition catalyst like montmorillonite clays for converting waste plastics into fuel grade hydrocarbon. These catalysts are low cost and effective in liquid conversion of waste plastics. In this paper, the process of converting waste Low Density Polyethylene (LDPE) and Polypropylene (PP) using Na-Montmorillonite clay catalyst at 400-440 °C into diesel grade oil with 60-70% yield is discussed. Theseresults were compared with fuel sample obtained using zeolite catalyst. [ABSTRACT FROM AUTHOR]

Polymer fibers made of low-crystalline polymers such as polyamide and low-density polyethylene have negative thermal expansion coefficient along the fiber axis and positive thermal expansion coefficient along the radial axis. Thus, as the temperature increases, the length of the fiber shrinks, and the diameter of the fiber expands. This thermal shrinkage is reversible to temperature changes in sufficiently heat-treated fibers. In 2014, Haines et al. published an efficient actuator that utilizes this reversible thermal shrinkage of fibers. This study aimed to clarify the mechanism of the anisotropic thermal expansion of polyamide fibers. The change in crystal orientation and birefringence due to thermal shrinkage were determined by wide-angle X-ray diffraction and polarizing microscopy. The change of amorphous orientation due to thermal shrinkage was calculated from those data and fiber crystallinity measured by DSC. Therefore, the slope of the amorphous orientation with respect to the reversible thermal shrinkage along the fiber axis was 4.1 for polyamide 6 and 2.49 for polyamide 610. This slope was significantly larger than that expected from the assumption of affine deformation. This suggests that the change of amorphous orientation was not the driving force for the thermal shrinkage of the fibers. Considering the thermal shrinkage of various polyamide fibers, the origin of the unique thermal expansion of the fibers was expected that the conversion of restricted axial thermal expansion of amorphous part to radial thermal expansion by fiber structure. [ABSTRACT FROM AUTHOR]

One of the key parameters of a country's socio-economic achievement is the construction of roads and highways. The technology for road construction has always been improved particularly in terms of quality and environmental aspects, for which the idea of using plastic emerged recently. Plastic roads are an auspicious strategy for lowering the quantity of land filled plastic, minimizing the dependency on depleted bituminous materials, and enhancing asphalt pavement performance. Assessing the environmental and human health aspects of the modified asphalt mixtures estimates the safety level of the product when exposed to the ecosystem. The objective of this study is to assess the preliminary environmental and human health hazards of our polypropylene (PP), high-density polyethylene (HDPE), and low-density polyethylene (LDPE) microplastics modified asphalt mixtures using fluorescence microscopy technique and polymer risk index. The mixtures were prepared by wet mixing the asphalt binder with different proportions of powdered microplastic polymers. The asphalt mixture that contained 100% HDPE had the highest crystal formation. Combining at least 5g of PP, reduced the risk index of the asphalt mixture. All the plastic polymers used in our study are ranked as the least environmentally hazardous chemicals. [ABSTRACT FROM AUTHOR]

In this paper, the mechanical behavior of recycled Low-Density Polyethylene (LDPE) plastic in composite materials as a matrix with fiberglass as reinforcement is studied. The composite materials were prepared with three different volume fractions of fiberglass (0, 7.5 and 22.5%) using hand-lay up method at 150°C. Impact, bending and tensile tests were performed. The results showed that the change of volume fraction from 0 to 7.5% led to an increase in the impact strength, yield stress and ductility, although there was a slight, ineffective decrease in tensile strength and flexural strength. When the volume fraction was changed from 7.5 to 22.5%, lead to increases in the impact strength, flexural strength, tensile strength, yield stress, modulus of elasticity and ductility. [ABSTRACT FROM AUTHOR]

In this research, a comparison between the Linear support vector machine (LSVM) and Quadratic support vector machine (QSVM) technique for estimating fouling layer thickness in Low density polyethylene (LDPE) tubular reactor process is performed. In practice, fouling is a form of polymer layer deposited inside the reactor wall, which is caused during thermodynamically driven phase separation of polymer (i.e., LDPE) and monomer (i.e., ethylene). The formation of fouling can reduce the heat transfer through the reactor's wall due to the low thermal conductivity of the deposited material. Thus, fouling can reduce the LDPE tubular reactor productivity by affecting the final polymer quality. However, the study of fouling formation for the LDPE tubular reactor process is hardly reported in the literature since it is hard to measure. Therefore, a machine learning technique, namely SVM, has been selected as soft sensor model to estimate the fouling thickness build-up inside LDPE tubular reactor, specifically in the cooling zone. In order to develop the SVM model, a set of fouling data is generated from a combination of LDPE tubular reactor model simulation using Aspen Dynamic and fouling build-up equation. In order to improve the soft sensor model, input selection, the Pearson correlation coefficient (PCC) method is implemented. Based on PCC analysis, polymer density, heat transfer coefficient, and reactor temperature in the respective cooling zone were considered as inputs for the developed soft sensor model. Based on the modeling results, the QSVM model performed better (with an R2 of 0.99) than the LSVM model (with an R2 of 0.97). Thus, the application of soft sensor model is using QSVM for the LDPE tubular reactor process is justified. [ABSTRACT FROM AUTHOR]

In this research, the pyrolysis of high and low-density polyethylene (HDPE and LDPE) plastic waste has been carried out at a temperature of 450-550 ℃ with a heating flow rate of 15 °C/min. The application of different temperatures is intended to determine the quality of the resulting fuel oil fraction so that the physical and chemical characteristics of the resulting liquid can be known. Parameters of the fuel oil quality were observed including density, viscosity, calorific value, and the amount of hydrocarbon compounds that is characterized using Gas Chromatography-Mass Spectrometry (GC-MS). As the results, this research showed the process of pyrolysis process at a temperature of 450 ℃ could not produce fuel oil, while at 550 ℃ it produced wax, so the analysis of the quality of the fuel oil was not carried out. LDPE fuel oil has a viscosity of 0.75-0.84 cP, a density of 0.750-0.764 g/ml, and a calorific value of 11,338-11,421 kcal/kg, while fuel oil from HDPE has a viscosity value of 0.631-0.765 cP, density 0.777-0.784 g/ml and calorific value 11,188-11,224 kcal/kg. The results of the GC-MS analysis show that the content of the gasoline fraction (C8-C12) for LDPE plastic waste is 60.6-81.3% and for HDPE plastic waste is 24.87 - 41.64%, while for the kerosene and diesel fraction (C13-C20) is 1.36-23.13% for LDPE plastic waste and 28.48 - 37.43% for HDPE plastic waste. The gasoline fraction (C5-C12) of LDPE and HDPE plastic waste showed more dominant results than the kerosene and diesel fraction. Therefore, LDPE and HDPE types of plastic waste can be produced into alternative fuel types of gasoline. [ABSTRACT FROM AUTHOR]

Pigments are widely used industrially, and it is known that they can act as nucleation agents in semicrystalline polymers, leading to changes in shrinkage and warpage. Variations in nucleation behaviour between different pigments can cause dimensional problems when parts are manufactured in a range of colours. It is widely known that some organic pigments such as reds and blue results in particularly high levels of nucleation and shrinkage. Previous studies have investigated the relationship between the effect of pigments addition on nucleation and the resulting shrinkage for a range of neat pigments using DSC (Differential scanning calorimetry). However, the effect of using masterbatch pigments with semicrystalline polymers is not fully understood. Masterbatch pigments are used much more widely than neat pigments due to the handling issues associated with liquids and powders. To understand the effect of masterbatch pigments on the crystallinity and shrinkage of semicrystalline polymers, 9 masterbatch pigments from a range of suppliers were added via injection moulding to LDPE (Low density polyethylene). The samples were analysed using DSC (Differential scanning calorimetry), XRD (X-Ray diffraction), FTIR (Fourier transform infrared spectroscopy) and tensile testing. DSC testing showed that adding pigment caused an increase in the onset temperature of crystallisation, and it was found that the magnitude of this nucleation effect was correlated with increased shrinkage. A correlation was also observed between the percentage crystallinity measured via DSC, XRD and FTIR and the measured shrinkage. It was observed that the orange, purple and lavender samples showed the largest changes in crystallinity and highest shrinkage. These results will be of interest to both polymer processors and companies involved in developing new masterbatch formulations. [ABSTRACT FROM AUTHOR]

This study investigates the effect of branching of linear low-density polyethylene (LLDPE) and POSS types on thermal, mechanical, and rheological properties and shapes memory behavior of crosslinked LLDPE/POSS composites using different concentrations of peroxide (PRX). Shape memory polymers (SMPs) are intelligent materials that can recall their original shape from the temporary shape by applying an external stimulus such as temperature and pH when they are deformed. In this work, polyethylene (PE) copolymers of 1-octene (LLDPE C8) and 1-hexene (LLDPE C6) were utilized as the PE types. Di-tert-butyl cumyl peroxide was used as peroxide in 0.5, 1, 2, and 3 phr ratios. Octavinyl POSS (OvPOSS) and Octaisobutyl POSS (OibPOSS) were used as potent co-agents. The composites were prepared in an Xplore micro-compounder. The crosslinking was carried out using a hot press. The composites were characterized by performing rheological, thermal, and shape memory tests. It was found that the viscosity, storage modulus, and crosslinking density of composites increased in the presence of OvPOSS than that of composites including OibPOSS; however, the gelation times decreased as PRX amount increased. Plasticizing effect of OibPOSS was obtained from rheology test results. It was observed from shape memory tests that OibPOSS decreased shape recovery ratio whereas OvPOSS increased. When the PE types were compared, the highest shape memory results were obtained with LLDPE C6. [ABSTRACT FROM AUTHOR]

Plastic waste in Indonesia in total reaches 189 kilograms tons/day. The types of plastic waste that are often found are low density polyethylene (LDPE), polystyrene (PS) and polyethylene terephthalate (PET). The aim of research are to describe the characteristic and to analyze the validation result of plastic simple recycler. The method used to treat LDPE, PS and PET plastic waste was pyrolysis. Plastic waste to be processed was cleaned and dried first to separate it from impurities. The time used in the experiment was 108 minutes with a temperature above 370°C. The results of LDPE and PET pyrolysis, can produce alternative energy. Based on the results of the validation tests, the mean rcount was 0.87 which indicates that the plastic simple recycler declared valid. The plastic simple recycler has six main component consist of a reactor, stove, the first and second alternative condensors, a basin, and a storage container. This plastic simple recycler has insteresting characteristics; easy to assembly and use, low cost and good pyrolysis performance. [ABSTRACT FROM AUTHOR]

As widely known, plastic has become an integral element of human culture. Despite posing a serious environmental hazard, plastic continuously used in a variety of domains ranging from industries to agriculture to our daily lives due to its lightness, sturdiness, inertness, and low cost. Low-Density Polyethylene (LDPE) is the thermoplastic that are commonly used to manufacture plastics bags and other plastic products. However, the excessive use of LDPE has caused a major environmental problem when they are accumulated in the environment. Currently, the physical and chemical methods of plastic degradation was proved to be inefficient and posed other environmental issues. As a result, eco-friendly methods like microbial plastic decomposition are being pursued as a better solution. This paper reports the potential ability of a Malaysian Rhodococci isolate obtained from Unisel Culture Collection (UCC), the Rhodococcus pyridinovoran strain UCC0018 in.LDPE biodegradation. The bacterium was cultured in nutrient broth supplemented with LDPE fine strips to evaluate the degradation of LDPE by weight reduction test. Results obtained demonstrated degradation activity where it reduced the weight of LDPE strips up to 5.2% after 24 hours of incubation. This result indicated the promising potential of Malaysian Rhodococcus in degrading LDPE. Based on this discovery, the initiative intends to cultivate the bacteria in large quantities, optimize the degradation activity, and work with the industry to turn the bacteria into a product that can be utilized to address Malaysia's plastic waste problem. [ABSTRACT FROM AUTHOR]

Plastic solid wastes such as bottled water bottles of the type of Polyethylene Terephthalate (PET) and food wrappers of plastic types Low-Density Polyethylene (LDPE) cause environmental problems. It is needed the processing methods that can overcome plastic waste. Thermal cracking or pyrolysis is one method of plastic waste treatment. All types of plastics were processed using a pyrolysis reactor at temperatures around 200 oC which successfully treated PET and LDPE plastic waste into liquid fuel and solid residuals. The quality of liquid fuel obtained was analyzed by GC-MS, caloric value, viscosity test, and density test. The oil produced from LDPE 100, PET: LDPE (10:90), and PET: LDPE (12.5: 87.5) had physical properties that were similar to gasoline, but based on the composition of hydrocarbons they were similar to solar (C9-C20). Meanwhile, liquid fuel obtained from PET: LDPE (15:85), had an abundance of aromatic compounds but paraffin was still identified. Therefore, this liquid fuel can be cracked to short-chain paraffin (C5-C10) to obtain gasoline. [ABSTRACT FROM AUTHOR]

The purpose of this study was to utilize residues of the plastic waste pyrolysis process and LDPE plastic as a substitute of cement in the manufacture of paving blocks. The residual pyrolysis process used was a pyrolysis residue of a mixture of polypropylene (PP) and low density polyethylene (LDPE) plastic waste with mass ratio of 100% PP, 75: 25%, 50: 50%, 40: 60%, 25: 75, and 100% LDPE. The mass ratio of LDPE plastic and pyrolysis residue were 70:30%, 60:40%, and 50:50%. The comparison of sand and residual pyrolysis of plastic waste used was 1: 1. The block paving obtained was characterized using SEM and quality tests were carried out with parameters of compressive strength and water absorption. The results of SEM analysis indicate the existence of a bond between sand and plastic pyrolysis residues. The variations in the type of plastic ratio in pyrolysis process indicate the varying of compressive strength and water absorption of the paving blocks. [ABSTRACT FROM AUTHOR]

The increase in mango fruit production is due to their high nutritional content, affordability, and relatively easy to find. However, like other horticultural crops, Mango can be easily bruised or damaged. The fruit damage can be caused by improper post-harvest handling, causing mango quality and short shelf life. The aim of this study to determine the shelf life and quality of Golek Mango stored in Zero Energy Cool Chamber (ZECC) using low-density polyethylene (LDPE) packaging and LDPE packaging with additional perforations. This research was conducted from January to March 2021 with two stages. The first stage was observing the physical quality of the fruit and then post-harvest treatment such as washing, packaging, and storing mangoes at ZECC temperature (±26 °C). The second stage was the mango quality test after storage. The analysis performed were weight loss, firmness, vitamin C, total acid, total dissolved solids, pH, water content, skin color, and sensory. The results obtained in this study were mangoes packed with LDPE and LDPE with perforations, respectively, 18 and 15 days. Mango packaged in LDPE packaging retained vitamin C, total acid, total dissolved solids, pH, the water content of L* color, b* color, organoleptic color, aroma, texture, and taste. Mangoes packed with perforated LDPE packaging can retain total dissolved solids, L* color, water content, b * color, organoleptic color, aroma, texture, and taste. [ABSTRACT FROM AUTHOR]

The continuous development of the 3D printing machines will bring a negative impact for the environment due to an increase in the amount of plastic waste that might occur. The production of 3D printing filament from recycled plastic material is one of the aLDPEropriate steps to overcome the problem of plastic waste, besides, this is also in line with the increasingly widespread use of 3D printing machines, especially with the FDM method. However, the right parameters are needed to process the filament from recycled plastic materials into printed product by considering the quality of the result. Therefore, this research was conducted with the aim to obtain the optimum process parameter toproduce the maximum product quality for 3D printing process with FDM technique using filaments from recycled plastic materials. This research uses a 3D Printing machine type FDM and recycled plastic filament of LDPE (Low Density Polyethylene)as printing material. The parameters are printing temperature, layer height and printing speed. The quality is measured by the dimensions which consist of length (x-axis) and width (y-axis), geometry which consist of perpendicularity and parallelism, and roughness of product surfaces. Data processing uses Taguchi method combined with PCR-TOPSIS. The results show that the optimum parameters for LDPE recycled filament are combination from printing temperature of 230 °C, 0.16 mm layer height and printing speed of 30 mm/s. The most decisive parameter to the quality of 3D printing products from recycled LDPE is printing speed. [ABSTRACT FROM AUTHOR]

Packaging can assist in preventing damage, protect materials from contamination and physical damage, and affect a material's shelf life. This study aimed to determine the shelf life of bakasang paste packaged using two types of packaging and evaluated using the accelerated shelf-life testing (ASLT) method. Bakasang paste (terasi) was made from the innards of skipjack or cakalang (Katsuwonus pelamis). The parameters evaluated in this study were water content, free fatty acid (FFA), and thiobarbituric acid (TBA). Bakasang paste was packaged using aluminum foil and low-density polyethylene (LDPE) and stored at 30°C, 40°C and 50°C for 0, 7, 14, 21, 28 days. The results indicated that Bakasang paste packaged in aluminum foil and stored at a temperature of 30°C had a shelf life of 758 days. [ABSTRACT FROM AUTHOR]

With the ever increasing demand of the construction materials due to unstoppable growth in the field of construction, there exists the need to go for substitutes of the natural resources. The resources that are apt fall in the line with sustainability and that enhances the properties of ultimate material. It has been observed that with the rapid growth in all directions there is a tremendous growth in the production of by products which are treated as waste and causes serious problems to the ecological system. With this perspective the stone crushers by product "prey dirt " and the menace to the society "waste low density polyethylene" has been the considered as the study material for studying the characterization properties. The microstructure characteristics of the materials which are treated as wastes will help to understand the compatibility with the concrete in terms of strength and durability. The constituents of the conventional concrete and the byproducts have been tested for x-ray crystallography and in order to test the longevity the controlled and modified concrete has been tested for rapid chloride penetration test. The dust has been taken in varying percentage from 0 to 100 % whereas the ldpe varies from 0 to 8 % as a modifier in concrete. It has been observed t from particle sizing that, the leanness of the prey dirt produced enhanced pore formation governing to impenetrable model. The petro graphical observation also showed absorbency of concrete specimen with natural sand mixes was on higher side which initiated cracking of matrix whereas with the inclusion of prey dirt and ldpe enhanced the pore structure model and the resistance improved to 20%. The research notifies that the long term conduct of concrete is governed by the formation of fine cleavages due to application of stress applied at initial stage which affects longevity and becomes vulnerable due to passage of water. [ABSTRACT FROM AUTHOR]

Plastic especially LDPE is the most common packaging bag in daily life because of its effective, light weight and low cost. LDPE is a material that so difficult to degrade in nature so it must be removed by the proper treatment. It is known that microorganisms have a role in the process of microplastic degradation. The aims of research to analyze the effect of the incubation period between microorganisms and microplastics (LDPE) in the biodegradation process based on analysis of morphological structures. The method is using scanning electron microscopy (SEM) to determine the changes of morphological structure that indicate the occurrence of the biodegradation process. The duration of incubation period was determined to be 10, 20, and 30 days with environmental temperatures set up at 25oC, 30oC, and 40oC. SEM analysis showed the changes of morphological structure in LDPE microplastics. The longest contact time of 30 days showed more significant morphological changes in LDPE. The environmental temperature also has an impact of biodegradation process, 30oC give the most changes of LDPE morphology structure. The implication of this research is finding the potential of microplastic biodegradation by analyzed the LDPE morphology change due to incubation period. Microplastic become a very serious problem for human health. Duration of incubation period is the important factor that effect the biodegradation process that need longer time to degrade. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the ability of 2 local bacteria (BPT1 and BPT6) isolated from a local dump soil in Pekanbaru Riau indegrading several types of plastic, namely conventional LDPE (Low-Density Polyethylene) plastic and oxo-biodegradable plastic, namely Oxium plastic. At the beginning of the test, morphological characterization and biochemical tests were carried out on both bacteria. The test of the ability of bacteria to degrade plastic was carried out by growing bacteria in a minimally synthetic medium (MSM) which was added to pieces of sterile plastic bags with a size of 10 x 3 cm. Incubation was carried out for 30 days using a shaker incubator at a speed of 150 rpm. The percentage of plastic degradation is calculated by measuring the initial weight and final weight of the plastic pieces. The results of the percentage degradation of BPT1 and BPT6 bacterial isolates for LDPE plastic were 0.33 ± 0.12%, 2.09 ± 1.76% and for oxium plastic were 1.71 ± 0.12%, 3.01 ± 1.11%. These results suggest that bacteria isolated from local dump soil may play an important role in overcoming the accumulation of plastic material in the soil. [ABSTRACT FROM AUTHOR]

Inverse fluidization is a type of fluidization process, in which a downward flow of a continuous liquid phase over a solid particle, whose density is lower than the density of the liquid. The parameters of hydrodynamics such as pressure drop, bed expansion, and minimum fluidization velocities were studied. In the present investigation, sodium Chloride (NaCl) and Sodium Carboxyl Methyl cellulose (SCMC) considered as a continuous liquid phase with low density particles of polyethylene (LDPE) and activated carbon from date seeds as a solid phase. Typical Pressure drop–superficial velocity plots and Bed expansion ratio - superficial velocity plots for different density variations using (5%, 10% and 15% NaCl solutions) and different viscosity variations using (0.1%, 0.3%, and 0.5% SCMC solutions) is shown and the bed expansion behavior is evaluated. [ABSTRACT FROM AUTHOR]

There have been various discussions concerning plastic items and their effects on the environment, with implications for business practices and public policies. However, making judgments without considering the trade-off circumstances between various plastic items may have a higher impact on other aspects of the life cycle. This study aimed to quantify the environmental impacts of various plastic jerry cans and choose which one to be used for student practice scenarios in Politeknik ATK Yogyakarta. Four different plastic jerry cans: polypropylene (PP), polyethylene terephthalate (PET), low-density polyethylene (LDPE), and high-density polyethylene (HDPE) were assessed from gate to gate approach in a comparative life cycle assessment (LCA). This study was performed using OpenLCA 1.10.3 and free European reference Life Cycle Database (ELCD) 3.2 Greendelta v2.18. The result showed that for CML-IA baseline method, LDPE jerry cans production has a better environmental performance among other plastic jerry cans in all impact categories (acidification, eutrophication, freshwater aquatic ecotoxicity, global warming, and human toxicity). It can be concluded that the practical needs of students in studying the production of plastic jerry cans are advised to use raw materials from LDPE granulates. Global warming has the highest impact result compared to other impact categories for each type of plastic. There are some improvement strategies to minimize the environmental impact, such as reducing the distance of LDPE transport, optimizing student practicum activities and ensuring the machinery operates efficiently, and substituting fossil-based plastics with eco-friendly plastics. [ABSTRACT FROM AUTHOR]

The development of polymer recycling is supported by research of degradation kinetics, pyrolysis products, and even reaction mechanisms. In this research, non-isothermal kinetic methods were used to estimate activation energies and to select the best fitting reaction models for high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), and polystyrene (PS). Pyrolysis is thermal heating of materials without oxygen and conversion into gas, liquid, and solid products. To perform an optimum pyrolysis, the degradation kinetics of plastic materials need to be studied. Fourier Transform Infra-Red Spectroscopy (FTIR) was used for characterization of initial materials and Thermogravimetry (TGA) was used to determine the degradation kinetics. Based on the results of the TGA, the optimal degradation temperature for plastic and mixed waste was determined from 380 to 500°C for each selected material. The kinetic method used is Coats-Redfern. From the results of the analysis, the activation energy range for thermal decomposition is 200–300 kJ/mol. This can indicate the minimum energy necessary for the pyrolysis process. [ABSTRACT FROM AUTHOR]

Low density polyethylene (LDPE) is a polymer material that is difficult to degrade in nature and causes waste to accumulate so that it can damage the environment. To overcome this, it is necessary to blend LDPE with poly(ε- caprolactone) (PCL), which is easily degraded. The PCL used in this research was obtained from ROP ε-CL using a bis(dibzm)2Zr catalyst. Meanwhile, the composition ratio of LDPE and PCL polyblend used is 10/4 (%w/w). Furthermore, the resulting LDPE/PCL polyblend plastic film was tested for biodegradation by using the fungus Aspergillus niger for 28 days. Aspergillus niger is a type of fungus that is able to decompose plastic waste. In general, the results of the biodegradation test showed that LDPE/PCL polyblend plastic films were more easily degraded compared to pure LDPE. [ABSTRACT FROM AUTHOR]

This study reports that oleic acid monomer and benzoyl peroxide initiator have affected the thermal properties and morphological of linear low-density polyethylene (LLDPE) grafted with oleic acid (OA) in a solvent system. This study aimed to determine the effect of increasing the OA monomer and benzoyl peroxide (BPO) initiator concentration on the grafting degree and thermal properties of LLDPE grafted with OA (LLDPE-g-OA). This research was conducted by dissolving LLDPE in xylene via the reflux method at 140 ℃, then adding an OA monomer and BPO initiator. The purification process with acetone and methanol was carried out to obtain purified LLDPE-g-OA. The results showed that the addition OA monomer of 15% and BPO of 5% obtained the maximum grafting degree (GD) percentage of all variations. A small band at 1707.1 cm−1 is the carbonyl group of OA, indicating that OA has been grafted onto LLDPE. Thermal properties indicate that LLDPE-g-OA is a semi-crystalline compound with a melting point of 123.1 ℃ and a decomposition temperature of 475.4 ℃. The morphology of LLDPE-g-OA has resulted in changes in the surface structure after grafting with oleic acid. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) is a plastic that cannot be degraded naturally. Therefore, processing is needed to prevent pollution from this plastic waste. In this research, LDPE plastic was processed into activated carbon and then composited with magnetite nanoparticles using the coprecipitation method with variations in the ratio of activated carbon and magnetite by 1:1 (ACM1), 1:2 (ACM2), and 1:3 (ACM3). The synthesized composites were tested for their ability as gram-positive and gram-negative antibacterial agents. Activation of carbon was carried out chemically using phosphoric acid. SEM characterization showed average particle sizes of 22.6 µm, 40.8 nm, and 25.3 µm for activated carbon, magnetite, and composites, respectively. In the ACM2 spectrum, the peak in wave number 570-575 cm−1 indicates Fe-O vibration while the broad peak at the wave number 3300-3500 cm−1 shows the O-H vibration and the formation of hydrogen bonds. Based on XRD spectrum analysis, the synthesized composite had similar peaks to those of Fe3O4 (COD 1010369) and activated carbon (COD 1200017). Hematite impurities detected in ACM1, ACM2, and ACM3 were 4.0%, 1.4%. and 0%, respectively. Based on the antibacterial test, the composite ACM3 had the best antibacterial activity against gram-positive bacteria (Staphylococcus aureus) but possessed a weak activity against gram-negative bacteria (Escherichia coli). [ABSTRACT FROM AUTHOR]

In this project, extruded rice husk (RH) / low density polyethylene (LDPE) with and without maleic anhydride (MAPE) were thermally treated at temperatures of 105C and 125C. The duration of annealing was carried out to one and three hours before going through to the injection moulding to get the dumbbell shape for tensile testing. From the testing, the trend of results obtained where tensile and modulus of elasticity of RH/LDPE increase with temperature of 125 C which are 5 MPa and 261 MPa respectively. However, the elongation at break shows a reduction value where 105 C temperature is 12% while 125C is 8%. Results obtained for RH/LDPE with and without MAPE show the composites with added MAPE have better tensile strength and modulus of elasticity. Meanwhile, the elongation at break of composites with MAPE is lower than composites without MAPE. [ABSTRACT FROM AUTHOR]

Currently, there is a rapid increase in the consumption of polymer materials. Due to the huge growth in agricultural and horticultural production, a significant amount of plastic waste is generated as a result of crop production and the use of mulching films. The combination of natural additives with synthetic polymers allows to develop environmentally friendly materials with increased biodegradability. In this article, we investigated composite films based on low-density polyethylene with addition of natural rubber. It has been shown that, in the process of mixing with polyethylene, partially vulcanized natural rubber is completely cross-linked, representing a hard rubber. This prevents large deformations from occurring in the composition under mechanical stress. The study of physical and mechanical properties showed that the use of natural rubber as natural additive allows to maintain acceptable performance properties. Thus, the results of this study indicate the possibility of using compositions based on polyethylene and natural rubber as packaging and agricultural films. [ABSTRACT FROM AUTHOR]

Biodegradation behavior of commercial plastics including high density polyethylene based plastic (HDPE), low density polyethylene based plastic (LDPE), linear low polyethylene based plastic (LLDPE), and a mixture of HDPE and LLDPE based plastic (OXO), was studied. The degradation test was performed by soil burial for 12 months in controlled condition in the laboratory. The weight change and morphology by visual and microscopic investigation were collected every 3 months. The test was conducted at 28-30 oC and 70-90% RH. All samples showed a significant increase in brittleness and turbidity after 6 months of soil burial. Significant weight loss was observed for OXO sample after just 3 months and continued to decrease even through 12 months, while the majority weight loss for HDPE, LDPE, and LLDPE occurred after 6 months of soil burial. The morphology of the HDPE and OXO samples showed only traces of erosion and large holes after the first 6 months. However, after 12 months, significant surface damage was observed. From these findings, soil burial under controlled temperature and humidity conditions in the laboratory environment may be conducive for microorganism growth that are able to effectively degrade polyethylene based plastic products. [ABSTRACT FROM AUTHOR]

In this work, polymer composite materials based on linear low-density polyethylene and iron oxide nanoparticles were obtained. Nanoparticles of iron oxide were synthesized in plasma discharge under ultrasonic cavitation. When preparing composite materials, the concentration of nanoparticles was varied from 0.5 to 20 wt. %. Measurements of elastic modulus as well as dynamic tests revealed the strong dependence of mechanic properties on the nanoparticle concentration. [ABSTRACT FROM AUTHOR]

In this work, polymer composite materials based on linear low-density polyethylene and nanoparticles of copper oxide were characterized in view of their physical and mechanical properties. Various concentrations of nanosized CuO filler were tested. It was found, that physical and mechanical properties of resulting composite depend on the filler concentration. Mechanical parameters were studied in static and dynamical regimes as well as temperature dependence of dynamic behavior of composite samples was examined. [ABSTRACT FROM AUTHOR]