Papers by Keyword: High Density Polyethylene (HDPE)

Abstract: In this paper, the catalytic co-gasification of rubber seed shell and high density polyethylene mixtures (0.2:0.8 weight ratio of HDPE:RSS) are investigated using a non-isothermal thermogravimetric analysis (TGA) system in a range of heating rates of 10, 20, 30 and 50 K/min within the temperature range of 323-1173 K. The argon gas is supplied at a flowrate of 100 ml/min and the steam is generated from superheater at 383 K. The steam is injected at flowrate of 300 μL/hour into the TGA system. A commercial nickel powder is used as the catalyst for the gasification process. The thermal decomposition behavior and synergistic effect of the HDPE/RSS mixture are investigated. The activation energy, E_A and pre-exponential factor, A are determined based on one step integral method.

Abstract: In metal injection molding, to identify the homogenous aluminum based feedstock is a challenging issues. In this study, a metal injection molding of aluminum feedstock which contains of high density polyethylene, stearic acid and paraffin wax as binder system was performed. The feedstock are used to produce tensile and gear shape green specimens using injection molding machine. The process ability of the metal injection molding feedstock depends on different parameters such as their binder composition and amount of metal powder used. From this study, the percentage of volume shrinkage experienced a sudden increase at the metal composition more than 50%. It also shown that, the paraffin wax content, affects the feedstock performances.

Abstract: In this paper, red phosphorous (RP) was coated by aluminum hydroxide to prepare modified RP (MRP). MPR was blended with high density polyethylene (HDPE) to obtain MRP/HDPE composites. And the properties of MRP/HDPE composites were investigated. The effects of MRP on the flame retardancy, thermal decomposition behavior and mechanical properties of HDPE were also discussed.

Abstract: Rapid industrial development causes serious problem all over the world such as depletion of natural aggregates and creates enormous amount of waste material from construction and demolition activities. Quantities of polymer wastes also have been increased these recent years due to the boost in industrialization and the rapid improvement in the standard of living. In Malaysia, most of polymer wastes is abandoned and not recycled. This situation causes serious problems such as wastage of natural resources and environmental pollution. Polymer products such as synthetic fibers, plastics and rubber belong to petrochemical compound and not easily biodegradable even after a long period. One of the ways to reduce this problem is to utilize waste materials in the production of concrete. Use of these materials not only helps in getting them utilize in cement, sand, aggregate, concrete and other construction materials, it helps in reducing the cost of concrete manufacturing, but also has numerous indirect benefits such as reduction in land-fill cost, saving in energy and protecting the environment from possible pollution effects. An experimental research is made on the utilization of plastic waste, High Density Polyethylene (HDPE) as coarse aggregates in concrete with a percentage replacement of 10 %, 20 % and 30 %. The laboratory tests include slump test, compressive strength and water absorption were conducted in this research. The samples content 10 % of HDPE has better performance in term of strength.

Abstract: In this dissertation, we studied the mechanical behaviors of HDPE fiber reinforced in cement mortar. One of our major concerns is to study the utilization of high strength high density polyethylene (HDPE) fibers obtained from different draw ratio melt spinning processing. Another major concern is to compare these fibers in term of mechanical behavior reinforced in cement mortar. We began with the material characterization, which mainly include different draw ratios with two sets of rollers through a glyceral bath set at 113°C. Draw ratio was calculated from the ratio of the speed of the follower to leader roller. The latter studies largely used three different fiber volumes fraction ratio tested mechanical properties of cement mortar by using the universal testing machine follow on ASTM standard testing. Subsequently, we studied the behaviors of HDPE fiber reinforced in cement mortar, which mainly include the flexural, tensile and compression strength. The development of mechanical strength of cement mortar when added with these fibers were presented characterize of cement mortar.

Abstract: The effect of vibration on the microstructure and mechanical properties of high-density polyethylene (HDPE) sheets, obtained through vibration plasticating extruder in low temperature, were studied systematically. Property Tests show that the tensile strength and the Vika temperature were much improved under the reciprocating axial vibration in low temperature. Differential scanning calorimetry , scanning electron microcopy and wide angle X-ray diffraction were executed to analyze the microstructure of the samples. The results indicate that the vibration extrudate in low temperature has higher crystallinity, perfect crystallite, and new crystal morphology formed , which account for enhancement of the mechanical properties and Vika temperature of sheets, compared to conventional static extrudate.

Abstract: The effective utilization of lignin waste has been a main concern in the bio-ethanol industry which uses straw and stalks as feedstock. In this study the lignin waste was incorporated into high density polyethylene (HDPE) to make composites by extruded pellet fabrication and thermoform process. With the increasing of the lignin content from 55% to 75%, the static flexural strength of the resulting blends was hardly influenced, but the tensile strength decreased 42%. The mechanical and dimensional stability tests both showed that the addition of 4% MAPE promoted the interfacial bonding between lignin and HDPE. The DSC analysis showed the presence of lignin scarcely influences the thermal behavior of pure HDPE and the composites.

Abstract: The thermal conductivity, electrical conductivity and mechanical properties such as tensile strength, elongation, modulus of elasticity, were experimentally investigated. Thermal and electrical conductivity measurements were performed up to filler concentration of 30 vol.%. The mechanical properties of high density polyethylene filled with up to 30 vol.% Cu particles were investigated. The tensile strength, elongation and toughness decreased with increasing Cu powder content. This was attributed to the introduction of discontinuities in the polymer structure in which modulus of elasticity increased with increasing the copper content.

Abstract: Nanocomposite films of ZnO/HDPE were prepared via melt blending and hot compression molding process. The morphology, DSC, mechanical and barrier properties of the films were investigated. The results showed that a better dispersion of modified nanoparticles at content of 0.5wt% in HDPE matrix occurred and the improvement of the HDPE films in tensile strength and tear strength was achieved by incorporating modified-ZnO nanoparticles up to 0.5wt% in contrast with the original nano-ZnO/HDPE composite films. It was also found that the addition of modified nano-ZnO to neat HDPE caused to increase crystallinity and enhance the barrier property of nano-ZnO/HDPE composite films against water vapor and oxygen.

Abstract: Extensional rheological properties of HDPE was measured and investigated by melt spinning techniques. It was observed that the melt strength of HDPE decreased with the rise of temperature. According to the slope of Arrhennius plots, melt strength activation energy was calculated. The curves of extensional stress and viscosity were plotted. Analysis of the results under different conditions indicated that with the rise of strain rate, the stress increased and the viscosity decreased, whereas higher temperatures yielded lower stress and viscosity. In addition, it was found that faster extrusion velocity caused lower level of extensional stress and viscosity during the experiment.