Papers by Keyword: Low Density Polyethylene (LDPE)

Abstract: The amount of plastic wastes and tire wastes were continuously increasing. The old tires and polymer which was low-density polyethylene (LDPE) were used to create polymer-modified pavement to get rid of plastic wastes and tire wastes replacing asphalt road. LDPE of 15 wt% was the main matrix material of the modified road pavement instead of asphalt; moreover, ground tire rubber (GTR) at various concentration of 3, 5, 7 and 10 phr was used as the additive mixed with mineral aggregates of 85 wt%. In this study, the Marshall method was used to prepare the sample. The properties of Marshall stability, Marshall flow, bulk specific gravity and voids of the polymer-modified pavement were studied for comparing to commercial asphalts. The results showed that the strength of the modified pavement increased which was higher than commercial asphalts although void concentration increased. The bulk specific gravity decreased as increasing amount of GTR. The percentage of water absorption increased as addition of GTR content. This study might be benefits in reduction of waste and valuable resources as bitumen, and also recovery an environment

Abstract: The presented article deals with the research of surface layer ́s micro-mechanical properties of modified LDPE by radiation cross-linking after temperature load. These micro-mechanical properties were measured by the DSI (Depth Sensing Indentation) method on samples which were non-irradiated and irradiated by different doses of the β – radiation and then were temperature loaded. The purpose of the article is to consider to what extent the irradiation process influences the resulting micro-mechanical properties measured by the DSI method. The LDPE tested showed significant changes of indentation hardness and modulus after temperature load.

Abstract: The experimental study deals with the effect of modification of the surface layer by irradiation cross-linking on the micromechanical properties of the low-density polyethylene (LDPE) tested using the instrumented nanohardness test. The surface layer of LDPE specimen made by injection technology was modified by irradiation cross-linking using beta irradiation, which significantly influences micromechanical properties of the surface layer. Compared to the heat and chemical-heat treatment of metal materials (e.g. hardening, nitridation, case hardening), cross-linking in polymers affects the surfaces in micro layers. These micromechanical changes of the surface layer are observed in the instrumented microhardness test. Our research confirms the comparable properties of surface layer of irradiated LDPE with highly efficient polymers. The subject of this research is the influence of irradiation dosage on the changes of micromechanical properties of surface layer of LDPE.

Abstract: This work presents the preparation of silver nanoparticles (AgNPs) with montmorillonite to produce a nanomaterial with bactericidal properties. The modified montmorillonite was characterized through the techniques of Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray diffraction (XRD). The FTIR and Raman spectrum’s showed specific bands of involving stretching silver. In the XRD analyses was observed the occurrence of the following crystallographic planes (111), (200) e (220) silver related. The nanocomposites of polyethylene with AgNPs did not show loss in mechanical properties, this fact was important and indicate that the nanomaterial can be inserted in this polymer matrix with considerable technological interest.

Abstract: Low density polyethylene (LDPE) and nanosilica (SiO₂) composites may offer many improved mechanical as well as electrical performance compared to a virgin LDPE. This study focuses on analyzing the partial discharge characteristic of LDPE nanocomposites. Different weight percentages (from 0 to 8wt%) of silica (SiO₂) nano particles were introduced as fillers into the LDPE base. The laboratory prepared nanocomposite samples were subjected to electrical stress or aging using the familiar CIGRE Method II setup. Partial discharge pulses were counted for both polarities for upto 60 minutes stress duration. The results show that the PD number of the samples is positively affected by the presence of nanosilica filler when the filler content is above 4wt%. The PD number of a virgin LDPE reduces to half when 8wt% of nanosilica filler is added irrespective of the PD polarities.

Abstract: This study was aimed to develop semi-biodegradable low density polyethylene (LDPE)/oil palm pressed fibre (PPF) composite film for agriculture applications such as nursery bag and plastic mulch. Biodegradability and water absorbency are among the properties need to be considered. Biocomposite plastic that rich with cellulose normally takes faster time to biodegrade as the fibres become the food source of microbes in soil. It also absorbs water easily due to hydrogen bonding formation between the cellulose and the water molecules. To have a balance between these properties is important to determine the service life of the film. Inorganic filler, stone powder with particle size of 37 micron was incorporated at 5, 10 and 15 phr into a mixture of LDPE/PPF, in order to improve both properties. The stone has undergone a catalytic transmuted process to produce fine powder using technology patented by Blapol Sdn Bhd. The mixture was compounded using twin screw extruder and palletized prior to blown into a sheet of film. The effects of stone powder onto water absorption and biodegradability were studied. The percentage of water absorption was decreased about 13 % with addition of 15 phr stone powder, which is thought due to the ability of stone powder to interfere the formation of hydrogen bonding between hydroxyl groups of cellulose and water molecules. Meanwhile, the weight loss in biodegradability test has been slow down, probably due to inorganic nature of stone powder that takes longer time to be digested by microbes in soil.

Abstract: This study analyzed nine polypropylene (PP) and low-density polyethylene (LDPE) blends where the mass concentrations of each sample were changed, proportionally. The aim was to investigate the tensile strength by means of these polymers best combination, before and after its exposal to gamma rays. The results showed that the 20/80 - PP/LDPE blend had a better performance concerning mechanical properties after irradiation, where the maximums tensile stress had an average increase of 30% in 30 and 50 kGy doses and 33% in the 200 kGy dose. On the other hand, it was verified that the higher blend's PP concentration, the higher its tensile strength will be (except for 100 kGy and 200 kGy doses which PP concentration over 70% can cause eventual degradation in the polymeric chains of the blend).

Abstract: This study investigates the properties of blends made from low density polyethylene (LDPE) with various levels of thermoplastic soya spent powder (SSP). The thermoplastic TPSSP content was varied from 5 to 20wt % whereas epoxidised natural rubber with 50 mol % (ENR 50) act as compatibilizer to improve the interfacial adhesion between low density polyethylene and thermoplastic TPSSP. The effect of the addition of ENR 50 on the LDPE/thermoplastic TPSSP was measured by using tensile test and thermal behaviour. The tensile strength and elongation at break (E_b) decreased with increasing TPSSP content. However, the addition of ENR 50 resulted in the increment of tensile strength and E_b LDPE/TPSSP blends.

Abstract: Sensitivity of the destructive doses of ionizing radiations, specifically radiolysis gaseous products to multipulse electric intensity of low-density polyethylene (LDPE) and a polymethyl-methacrylate (PMMA) was investigated. LDPE and PMMA were found to differ significantly depending on radiation resistance and gas permeability. The service life of the materials was basically determined by the intensity of the destruction processes at the molecular level, the macrodefects were developed at the last ageing stage . It was shown that microseconds impulses did not cause accumulation of volume charge in LDPE and PMMA. It was concluded that the ageing of polymer dielectrics affected by electric microseconds impulses did not relate to volume charge accumulation in the polymers.

Abstract: The spear grass content on the tensile properties, morphology of low-density polyethylene (LDPE)/spear grass was investigated. The compatibilising effect of epoxidised natural rubber (ENR 50) LDPE and spear grass was mixed by using twin screw extruder with various spear grass contents. The tensile properties were tested by using an Universal Testing Machine (UTM). The tensile strength and elongation at the break point were significantly improved by the addition of ENR 50, as evidenced by morphological analysis using scanning electron microscopy (SEM). On the other hand, the tensile modulus increased with spear grass content up to 10% and decreased thereafter.Keywords: Epoxidised Natural rubber (ENR), Low Density Polyethylene (LDPE), Spear Grass, Tensile Properties