Low-density Polyethylene Material Research Articles

Experimental characterization of aluminum/polymer/aluminum sandwich structures under various loading rates and temperatures: Establishing a constitutive relationship for LDPE

Composite sandwich structures, for example Alucobond, have appeared as auspicious materials in a diversity of engineering applications due to their lightweight, high strength to weight ratio and thermal insulation properties. Analyzing their mechanical behavior in different loading rates is critical to optimizing their performance. This study inspects the mechanical response of Alucobond sandwich composite structures under dynamic and quasi-static compression loadings. Dynamic compression tests, carried out at high strain rates, and quasi-static compression tests, carried out at lower strain rates and temperatures, were used to predict the behavior of the material under different loading conditions. In addition, the mechanical properties of the low-density polyethylene (LDPE) core layer were characterized under dynamic and quasi-static loading conditions, with varying strain rates and temperatures, leading to the establishment of a constitutive relationship for the LDPE material. The comparative study of Alucobond and LDPE highlights the influence of material composition and loading conditions on the mechanical behavior of the composite sandwich structures.

Analysis of Mechanical Properties and Structural Analysis According to the Multi-Layered Structure of Polyethylene-Based Self-Reinforced Composites.

In this research, a self-reinforced composite material was manufactured using a single polyethylene material, and this self-reinforced composite material has excellent recyclability and is environmentally friendly compared to composite materials composed of other types of material, such as glass fiber reinforced composites (GFRP) and carbon fiber reinforced composites (CFRP). In this research, the manufactured self-reinforced composite material consists of an outer layer and an inner layer. To manufacture the outer layer, low density polyethylene (LDPE) films were laminated on high density polyethylene (HDPE) fabrics and knitted fabrics, and composite materials were prepared at various temperatures using hot stamping. A 3D printing process was utilized to manufacture the inner layer. After designing a structure with a cross-sectional shape of a triangle, circle, or hexagon, the inner layer structure was manufactured by 3D printing high-density polyethylene material. As an adhesive film for bonding the outer layer and the inner layer, a polyethylene-based self-reinforced composite material was prepared using a low-density polyethylene material. Input data for simulation of self-reinforced composite materials were obtained through tensile property analysis using a universal testing machine (UTM, Shimadzu, Kyoto, Japan), and the physical property values derived as output data and actual experimental values were obtained. As a result of the comparison, the error rate between simulation data and experimental data was 5.4% when the shape of the inner layer of self-reinforced composite material was a hexagon, 3.6% when it was a circle, and 7.8% when a triangular shape showed the highest value. Simulation in a virtual space can reduce the time and cost required for actual research and can be important data for producing high-quality products.

Use of Panels Made from Plastic Waste in Thermal Insulation

The materials of the given article are devoted to the problem solution associated with one of the processing plastic waste methods by adding various fillers in order to obtain the final product for the thermal insulation materials manufacture. The researches were conducted using the UPR (unsaturated polyester resin) samples made of EPS (expanded polystyrene) plastic waste and crushed recycled polyethylene from greenhouse film waste with various types of wood waste from carpentry workshops. The tests have revealed that when EPS is added to the unsaturated polyester mixtures, the EPS thermal conductivity coefficient decreases with a slight decrease in density, which gives the wide opportunities to use EPS waste as an additive for UPR and expands the ways of its potential industrial application, and the addition of styrene to the compositions containing 10% of styropor causes a clear decrease in thermal conductivity characteristics and a slight decrease in the density of these mixtures. The values of the thermal conductivity coefficient and the density of the low-density polyethylene material increase with the wood powder percentage raising used as an organic filler.

Jute and kenaf carrier bags: an eco-friendly alternative to plastic bags in India.

Increasing demand for shopping and packaging carrier bags has given rise to various issues relating to its disposal as well as to the overall environmental footprint and sustainability of the packaging materials. This study assesses the carbon footprint and life cycle environmental impacts of the production, usage, and disposal of low density polyethylene (LDPE) and two natural fibre carrier bags (jute and kenaf). Life cycle assessment study was conducted of all inputs and outputs, aggregated in the form of resources used and environmental emissions, extending from the production of raw materials to the final disposal of the product. The carbon footprint and GHG emissions of jute and kenaf carrier bags were estimated using the CO2, N2O, and CH4 emissions coefficients of inputs. Research literature from life cycle impact assessment (LCIA) results was used to determine the effects of LDPE polyethylene packaging material. It was observed that the global warming potential (GWP) for the production of 1 kg of LDPE (100 micron) carrier bag (39.4 kg CO2eq) is more than 490 times higher than jute and kenaf carrier bags. In general, LDPE materials have the greatest impact on the carbon footprint and resource depletion. The LDPE material also has the highest impacts on indicators of terrestrial ecotoxicity, photochemical oxidation, acidification, and eutrophication as compared to jute and kenaf fibres. Since jute and kenaf are natural fibres, they sequester a substantial quantity of carbon during their agricultural stages. As a result, greenhouse gas (GHG) emission emissions of jute and kenaf were found to be negative. Popularising the use of jute and kenaf products as alternatives to plastic in industrialised countries would benefit the reduction of plastic waste and its negative environmental effects. Additional production of jute and kenaf fibre, which are already available in major bast fibre producing countries like India and Bangladesh, could meet the demand for fibre-based carrier bags.

Structure-property behavior of polyethylene nanocomposites containing Bi2O3 and WO3 as an eco-friendly additive for radiation shielding

A new polymer based on nanocomposites was prepared to examine its radiation-shielding properties for potential industrial applications. Bismuth oxide (Bi2O3) nanoparticles and flower tungsten oxide nanostructures (FL-WO3) was hydrothermal synthesized. The Bi2O3 nanoparticles and WO3 nanostructure formation were confirmed using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy (TEM). The Bi2O3 nanospheres had an average diameter of approximately 30–68 nm. The WO3 nanostructure and Bi2O3 nanoparticles were incorporated into low density polyethylene (LDPE) to fabricate a nanocomposite. The radiation-shielding performance of different nanocomposites was investigated. The results showed that LDPE loaded with WO3, WO3/Bi2O3, and Bi2O3 displayed higher tensile strength and thermal stability than unloaded LDPE. The results showed that the LDPE loaded with 3% Bi2O3 performed better gamma attenuation at 662, 1173, and 1332 keV. Additionally, WO3, WO3/Bi2O3, and Bi2O3 as ecofriendly additive-reinforced LDPE materials have a gamma-ray-shielding performance. The results indicate that LDPE containing Bi2O3 have higher gamma-ray-shielding properties than other nanocomposites.

Investigation of the Mechanical Behavior of a New Generation Wind Turbine Blade Technology

Wind turbine blades are one of the largest parts of wind power systems. It is a handicap that these large parts of numerous wind turbines will become scrap in the near future. To prevent this handicap, newly produced blades should be recyclable. In this study, a turbine blade, known as the new generation of turbine blade, was manufactured with reinforced carbon beams and recycled, low-density polyethylene materials. The manufacturing addressed in this study reveals two novelties: (1) it produces a heterogeneous turbine blade; and (2) it produces a recyclable blade. In addition, this study also covers mechanical tests using a digital image correlation (DIC) system and modeling investigations of the new generation blade. For the mechanical tests, displacement and strain data of both new generation and conventional commercial blades were measured by the DIC method. Instead of dealing with the modeling difficulty of the new generation blade’s heterogeneity we modeled the blade structural system as a whole using the moment–curvature method as part of the finite element method. Then, the behavior of both the new generation and commercial blades at varying wind speeds and different angles of attack were compared. Consequently, the data reveal that the new generation blades performed sufficiently well compared with commercial blades regarding their stiffness.

A novel synthesis of light transmission from upcycled polyethylene terephthalate polymer and low-density polyethylene for greenhouse design in tropical climate

Abstract To support the circular economy in Thai’s agriculture, the main interviewed challenges point to knowledge and knowhow for greenhouse structure and system boosting up productivities. One popular material that possibly affected productivity is transparent polymer film, which can be recycled based on material property and blowing machine condition. This paper investigates the light transmittance performance of transparent polyethylene terephthalate polymer (PET) and low-density polyethylene (LDPE) sheets for use in low-energy greenhouses in tropical climates. The aim of the study is to optimize the thermal performance and light transmittance of these materials to support plant growth and human comfort. The study focuses on seven stages of plant growth, each of which requires different light characteristics including 1) seed, 2) germinating, 3) young seedling, 4) older vine, 5) flowering, 6) fruit bearing and 7) harvesting and drying. Each stage requires different light characteristics, e.g. light intensity, red light, blue light, white light and ultraviolet (UV) and pulsed light (PL). The methodology involves selecting PET and LDPE materials, preparing samples for thermal property and lighting laboratory tests and analysing the results based on suitable criteria. The findings show that LDPE sheets have 28.78% lower light transmittance than PET sheets, making them suitable for supporting the seedling stage and older vines of plant growth. PET sheets, on the other hand, deliver a high intensity of red light, making them suitable for stimulating photosynthesis in older vines and during the harvesting process. The study highlights the importance of considering both thermal performance and light transmittance when selecting materials for low-energy greenhouses in tropical climates.

Temperature modulated DSC for composition analysis of recycled polyolefin blends

Post-consumer plastic waste contains blends of numerous types of polyethylene (PE) and isotactic polypropylene (i-PP), whose recycling is challenging due to the complexity of this waste stream. A comprehensive knowledge of the composition of these recyclates is essential to understand the structure-property relationship of these systems and therefore upcycle them for high-value applications. To this aim, we used Temperature Modulated DSC (TM-DSC) to develop a quantitative method to evaluate PE and Low-density PE (LDPE) content in recycled polyolefin blends. TM-DSC was carried out on 29 virgin PE materials, spanning densities between 960 and 862 kg/m3, characterizing a wide range of PE microstructures. Moreover, several PE/i-PP model blends were prepared by selecting LDPE, High-density PE (HDPE) and Linear Low-density PE (LLDPE) materials to blend them with i-PP of three types: homopolymer (PP–H), block copolymer (PP–B) and random copolymer (PP-R), mimicking the composition of real recyclates. Results from the TM-DSC analysis of these blends allowed us to establish methods for quantifying the amount of overall PE content and also the LDPE fraction within recyclates. The developed methods were applied to real post-consumer recycled grades, and results were compared with the ones obtained from Cross-Fractionation Chromatography (CFC) analysis and Nuclear Magnetic Resonance (NMR) spectroscopy, displaying good agreement between the latter and the TM-DSC method.

Efficiency of halophilic biofilm producing bacteria towards the degradation of plastic materials at optimum temperature

The consumption of plastic has drastically increased leads to the plastic waste and became the global issue. In the present study, the screening of bacterial isolates from saline areas along with their microbial and biofilm efficiency in degradation of low-density polyethylene (LDPE), high density polyethylene (HDPE) and polypropylene plastic materials were estimated at two different temperatures (30°C and 37°C). The soil samples were collected from salt-affected lands for the isolation and characterization of bacterial isolates. The isolated strains were characterized by 16S rRNA. Two bacterial strains (Bacillus subtilis and Enterobacter cloacae) were identified through sequencing (BioEditor Sequence Builder) among the selected bacterial isolates. Effective degradation rate has been observed through B. subtilis towards LDPE, HDPE and polypropylene as 18%, 25% and 42% respectively through biofilm, while the degradation rate in TSA media were observed as 32%, 30% and 52% respectively, at 37°C. Similarly, E. cloacae degrades the LDPE, HDPE and polypropylene material at 12%, 15% and 30% through biofilm, however 19%, 18% and 38% degradation rate were observed at 37°C respectively. Therefore, both bacterial strains (MK2 B. subtilis and MK29 E. cloacae) isolated from salt-affected area showed potential to degrade the plastic materials at optimum temperature of 37°C.

Linear solvation energy relationships (LSERs) for robust prediction of partition coefficients between low density polyethylene and water. Part I: Experimental partition coefficients and model calibration

When equilibrium of leaching is reached within a product's duty cycle, partition coefficients polymer/solution dictate the maximum accumulation of a leachable and thus, patient exposure by leachables. Yet, in the pharmaceutical and food industry, exposure estimates based on predictive modeling typically rely on coarse estimations of the partition coefficient, with accurate and robust models lacking. This first part of the study aimed to investigate linear solvation energy relationships (LSERs) as high performing models for the prediction of partition coefficients polymer/water. For this, partition coefficients between low density polyethylene (LDPE) and aqueous buffers for 159 compounds spanning a wide range of chemical diversity, molecular weight, vapor pressure, aqueous solubility and polarity (hydrophobicity) were determined and complimentary data collected from the literature (n=159, MW: 32 to 722, logKi,O/W: -0.72 to 8.61 and logKi,LDPE/W: -3.35 up to 8.36). The chemical space represented by this compounds set is considered indicative for the universe of compounds potentially leaching from plastics. Based on the dataset for the LDPE material purified by solvent extraction, a LSER model for partitioning between LDPE and water was calibrated to give:logKi,LDPE/W=−0.529+1.098Ei−1.557Si−2.991Ai−4.617Bi+3.886Vi. The model was proven accurate and precise (n = 156, R2 = 0.991, RMSE = 0.264). Further, it was demonstrated superior over a log-linear model fitted to the same data. Nonetheless, it could be shown that log-linear correlations against logKi,O/W can be of value for the estimation of partition coefficients for nonpolar compounds exhibiting low hydrogen-bonding donor and/or acceptor propensity. For nonpolar compounds, the log - linear model was found as: logKi,LDPE/W=1.18logKi,O/W−1.33 (n = 115, R2=0.985, RMSE=0.313). In contrast, with mono-/bipolar compounds included into the regression data set, an only weak correlation was observed (n= 156, R2 = 0.930, RMSE = 0.742) rendering the log-linear model of more limited value for polar compounds. Notably, sorption of polar compounds into pristine (non-purified) LDPE was found to be up to 0.3 log units lower than into purified LDPE. To identify maximum (i. e. worst-case) levels of leaching in support of chemical safety risk assessments on systems attaining equilibrium before end of shelf-life, it appears adequate to utilize LSER - calculated partition coefficients (in combination with solubility data) by ignoring any kinetical information.

Study of Mechanical Properties of Recycled Polyethylene of High and Low Density

High and low density polyethylene materials constitute about 48% of total weight of plastics waste in Europe, that depends on the frequent use of these materials in packaging applications. This paper analyze the recycling effect on the mechanical properties of high and low density polyethylene (HDPE and LDPE). A mechanical recycling process was tested for the plastics waste of high and low density polyethylene, then a tensile and impact tests were performed on different mixing ratios for each of the both materials ranging from 100% of the virgin material and up to 100% of the recycled material with a difference of 10% of the sample to the other. This paper discusses the tensile properties of tensile stress at the fracture, elongation and modulus of elasticity and the impact test results for HDPE and LDPE were compared with each other.

Composite Micro-Nanoarchitectonics of MMT-SiO2: Space Charge Characteristics under Tensile State.

Low density polyethylene (LDPE) is a good insulating material which is widely used in cable materials due to its excellent insulation and processability. However, in the DC high voltage environment, pure polyethylene materials still face many problems, the most serious of which is space charge accumulation. The cable will inevitably be subjected to tensile stress during production, installation and operation. Therefore, it is of great significance to study the effect of stretching on the microstructure and space charge characteristics for polymers and their composites. In this paper, MMT/LDPE micro-composites, SiO2/LDPE nano-composites and MMT-SiO2/LDPE micro-nano-composites were prepared by melt blending. Mechanical stretching was carried out on pure LDPE materials and the above three kinds of composite materials. Each material was stretched according to four stretching ratios, which are 0%, 5%, 10% and 20%. The crystal morphology was observed by polarizing microscope (PLM), the crystallization perfection was tested by differential scanning calorimetry (DSC), and the space charge distribution inside each sample was measured by pulsed electro-acoustic (PEA) method. At the same time, the average charge density and apparent charge mobility for samples during depolarization were calculated and analyzed. The experimental results show that when the pure low density polyethylene sample is not stretched, its crystal structure is loose. Tensile stress can make the loose molecular chains align in LDPE and improve its crystalline structure, which is helpful to restrain the accumulation of space charge inside the sample. For MMT/LDPE, SiO2/LDPE and MMT-SiO2/LDPE composites, their internal crystal structure is compact. Stretching will destroy their original crystal structure at first, and then disorder molecular chains inside the three composite materials. With the increase of stretching ratio, the molecular chains begin to orient along the direction of force, the crystallization tends to be perfect gradually, and the space charge accumulation in samples also decreases. From the calculation results of apparent charge mobility for each sample, with the increase of stretching ratio, the trap depth and trap density inside samples firstly increased and then decreased.

Mechanical and thermal behavior of plantain peel powder filled recycled polyethylene composites

Abstract In the arduous search for ways to clean up the environment and produce viable materials from waste plastics; plantain peel powder filled low density polyethylene wastes (wLDPE) were developed through melt mixing and compression moulding techniques. Optimum properties were determined at 15, 55 and 30 % formulation of plantain peel powder, and Kankara clay respectively. Composition with optimum properties has tensile strength of 55.5 MPa, flexural strength of 50.45 MPa and elastic modulus of 2.30 GPa with corresponding minimal water absorption of 0.95% after 30 days immersion period at room temperature. The thermal properties investigated by Dynamic Mechanical Analysis showed that the composite has better thermal stability at higher temperature than wLDPE. Similarly, through creep analysis, the composite was observed to have better load bearing capability at elevated temperature than waste low density polyethylene material. These results indicate that incorporation of treated plantain peel powder and Kankara clay into wLDPE enhanced the mechanical, thermal and creep resistance of wLDPE. This implies load bearing capability and potential suitability for different wall tiles applications.

LDPE Transformation by Exposure to Sequential Low-Pressure Plasma and TiO2/UV Photocatalysis.

Low-density polyethylene (LDPE) sheets (3.0 ± 0.1 cm) received sequential treatment, first by the action of direct-current low-pressure plasma (DC-LPP) with a 100% oxygen partial pressure, 3.0 × 10−2 mbar pressure, 600 V DC tension, 5.6 cm distance, 6-min treatment. Then, sheets were submitted to TiO2 photocatalysis at UV radiation at 254 nm (TiO2/UV) with a pH value of 4.5 ± 0.2 and a TiO2 concentration of 1 gL−1. We achieved a complementary effect on the transformation of LDPE films. With the first treatment, ablation was generated, which increased hydrophilicity. With the second treatment, the cavities appeared. The changes in the LDPE sheets’ hydrophobicity were measured using the static contact angle (SCA) technique. The photocatalytic degradation curve at 400 h revealed that the DC-LPP photocatalysis sequential process decreased SCA by 82°. This was achieved by the incorporation of polar groups, which increased hydrophilicity, roughness, and rigidity by 12 and 38%, respectively. These sequential processes could be employed for LDPE and other material biodegradation pretreatment.

Optimisation of Shrinkage and Strength on Thick Plate Part Using Recycled LDPE Materials.

Achieving good quality of products from plastic injection moulding processes is very challenging, since the process comprises many affecting parameters. Common defects such as warpage are hard to avoid, and the defective parts will eventually go to waste, leading to unnecessary costs to the manufacturer. The use of recycled material from postindustrial waste has been studied by a few researchers. However, the application of an optimisation method by which to optimise processing parameters to mould parts using recycled materials remains lacking. In this study, Response Surface Methodology (RSM) and Particle Swarm Optimisation (PSO) methods were conducted on thick plate parts moulded using virgin and recycled low-density polyethylene (LDPE) materials (100:0, 70:30, 60:40 and 50:50; virgin to recycle material ratios) to find the optimal input parameters for each of the material ratios. Shrinkage in the x and y directions increased in correlation with the recycled ratio, compared to virgin material. Meanwhile, the tensile strength of the thick plate part continued to decrease when the recycled ratio increased. R30 (70:30) had the optimum shrinkage in the x direction with respect to R0 (100:0) material where the shrinkage increased by 24.49% (RSM) and 33.20% (PSO). On the other hand, the shrinkage in the y direction for R30 material increased by 4.48% (RSM) and decreased by 2.67% (PSO), while the tensile strength of R30 (70:30) material decreased by 0.51% (RSM) and 2.68% (PSO) as compared to R0 (100:0) material. Validation tests indicated that the optimal setting of processing parameter suggested by PSO and RSM for R0 (100:0), R30 (70:30), R40 (60:40) and R50 (50:50) was less than 10%.

Modelling the conduction mechanisms in low density polyethylene material using finite element method

Polymers used as insulating materials are increasingly popular in many different fields. In electrical engineering - electronics, polymers are used in high-voltage transmission cables, capacitors, transformers, or as part of an embedded system in the IGBT module thanks to its superior thermal and electrical insulation properties. One of the disadvantages of polymers is the possible accumulation of space charge in the material volume for a long time, leading to an increase in the electric field compared to the original design value. Charge transport models in polymer materials have been increasingly developed to predict the conduction mechanisms under thermal-electrical stress. In this study, from a finite volume method (FVM), the authors developed a charge transport model in low density polyethylene (LDPE) based on the finite element method (FEM). The simulation results of this model are also compared to experimental results and to the FVM model under different electric fields for LDPE.

Catalytic C–H Oxidation Enhances Polyethylene Bonding

Selectively adding functionality to commodity plastics is an abiding challenge in polymer science. In this issue of Chem, Hartwig and co-workers describe a selective, catalytic oxidation of polyethylene C–H bonds by using high-valent ruthenium-oxo species. The transformation increases polyethylene’s adhesive properties without significantly modifying its thermal stability or mechanical strength.

THE EFFECTS OF HIGH DENSITY POLYETHYLENE ADDITION TO LOW DENSITY POLYETHYLENE POLYMER ON MECHANICAL, IMPACT AND PHYSICAL PROPERTIES

Polyethylene materials are the most widely used polymers which we encountered everywhere in our daily life. Some of the advantages of the polyethylenes are the diversity of production types, corrosion resistance, electrical insulation and recyclability. The main production methods are compression molding, transfer molding, rotational molding, injection molding, gas-assisted injection molding, extrusion and blown film extrusion techniques. It is possible to increase the mechanical properties of low density polyethylene materials by addition of high density polyethylene materials. Both polymer has same monomers but their chemical structure and bonding properties are different. Their physical properties can change with their chemical structure and bonding properties. In this study, 25%, 50% and 75% by weight of high density polyethylene were added to low density polyethylene. Granules were pre-mixed with a mechanical mixer before production of the samples. Plastic injection molding machine was used for specimen preparation. Density, hardness, tensile test, three-point bend test, compression test, tear test and Izod impact tests were performed. Densities and hardness values of the polymer blends decrease by the increasing amount of low density polyethylene. In general, it was observed that the mechanical properties of the polymer blends increase as the high density polyethylene content increase.

Competitive heavy metal adsorption onto new and aged polyethylene under various drinking water conditions

The study goal was to identify factors that influence copper (Cu), iron (Fe), lead (Pb), manganese (Mn), and zinc (Zn) loading on new and aged low-density polyethylene (LDPE) under various drinking water conditions. The applied aging procedure increased LDPE surface area, hydrophilicity and the number of oxygen containing functional groups. Aged LDPE adsorbed up to a 5 fold greater metals than the new LDPE: Cu > Pb, Zn > Mn. Water pH (5.5 to 10.5) significantly altered LDPE surface metal loading. The organic carbon leached from plastic pipes inhibited Cu adsorption (−43.8%), but other metals were less impacted (−5.7% to −9.1%). The addition of free chlorine and corrosion inhibitor retarded metal adsorption to suspended LDPE materials. Overall, by changing water conditions total metal loadings (i.e., Cu, Mn, Pb and Zn) were altered 20.1 to 35.4%. When Fe was present, Cu (−4.0%) and Pb (−4.5%) loadings were reduced, while lesser impacts were found for Mn and Zn. Cu2+, Pb2+ and Zn2+ hydroxides and oxides were identified as the major metal deposit forms on the LDPE surface by XPS. To better predict metal fate in plastic piping systems, plastic surface characteristics, dissolved organics, water pH, hydraulic conditions and microbial growth should be considered.

Space Charge Characteristics and Electrical Properties of Micro-Nano ZnO/LDPE Composites

The synergistic effects of zinc oxide (ZnO) Micro/Nano particles simultaneously filled in low-density polyethylene (LDPE) on the space charge characteristics and electrical properties has been investigated by melt blending micro-scale and nanoscale ZnO additive particles into LDPE matrix to prepare Micro-ZnO, Nano-ZnO, and Micro-Nano ZnO/LDPE composites. The morphological structures of composite samples are characterized by Polarizing Light Microscopy (PLM), and the space charge accumulations and insulation performances are correlated in the analyses with Pulse Electronic Acoustic (PEA), DC breakdown field strength, and conductance tests. It is indicated that both the micro and nano ZnO fillers can introduce plenty of heterogeneous nuclei into the LDPE matrix so as to impede the LDPE spherocrystal growth and regularize the crystalline grains in neatly-arranged morphology. By filling microparticles together with nanoparticles of ZnO additives, the space charge accumulations are significantly inhibited under an applied DC voltage and the minimum initial residual charges with the slowest charge decaying rate have been achieved after an electrode short connection. While the micro-nano ZnO/LDPE composites acquire the lowest conductivity, the breakdown strengths of the ZnO/LDPE nanocomposite and micro-nano composite are, respectively, 13.7% and 3.4% higher than that of the neat LDPE material.