Papers by Keyword: High Density Polyethylene (HDPE)

Abstract: The objective of the current work is to analyze the influence of water cooling of high density polyethylene (HDPE) sheet welding by friction stir process (FSW) on mechanical strength, based on microhardness tests. In the present work, the process using the conventional tool (C-FSW) is presented with the new procedure developed for FSW for HDPE, called water conventional friction stir welding (W-FSW). Test results for water-cooled and non-cooled welded samples were compared. HDPE sheets were initially welded by FSW process, and intensive water cooling was performed to weld after the tool exceeded the initial welding position by 30mm. The tool rotation speed of 1100 rpm and welding speed of 26 mm/min was used. The results were compared and evaluated with the hardness tests. A decrease in the hardness was observed when the sheets were treated by quenching, especially in the weld cores. It was found that the average hardness was much lower than that of untreated welded plates. Additionally, there is a region outside the core that has more or less the same stiffness value. The use of intensive quenching and conventional tooling has proven to be of great importance in improving surface finish, reducing defects, and increasing the mechanical strength of welds. The resulting recrystallization modified the hardness and thus increased the efficiency of the joint. These findings indicate the welding quality of the studied polyethylene.

Abstract: Sawdust is a waste from furnitureindustry which is mostly left in the garbage or burn for landfill in hugequantities every year. Efforts to find utilization of this material haveresulted mostly in low value. However, sawdust waste can be considered as analternative to fabricate fiber reinforced polymer composites for furniturefunction. This study was undertaken to determine the physical and mechanicalproperties of wood plastic composites, which were made under laboratoryconditions by hot pressing of high-density polyethylene (HDPE) with teakwoodsawdust as filler. Seven levels of mixed flour, 10, 20, 30, 40, 50, 60 and 70%,based on the composition by weight was added to the HDPE powder with palm oilas coupling agent. A flat pressing technology, the simplest method for capableof large dimension wood plastic panel production, was used to manufacturetesting specimens in dimensions 5.8 x 7.3 cm². Investigation of themechanical property of the composites material, according to the Americansociety for testing and materials (ASTM) method, was done by impact strengthtester. The measurement results were found that impact strength was decreased uponthe increasing of the sawdust up to 30 % mixing then gradually increased. However,by increasing mixed flour content, water resistance of the panels wasnegatively influenced. The best appearance of composites material in comparisonwith the natural woods was ~30% sawdust powder mixing. The woodplastic panels were utilized for construction of a Thai spirithouse as an outdoor decoration.

Abstract: In this work, accelerated ultraviolet (UV) aging of high density polyethylene (HDPE) was prepared, and tensile tests, Shore D hardness test and small punch test (SPT) were carried out. The macroscopical morphology of tensile fracture and microscopical morphology of SPT have been observed successively. The result showed that HDPE aging significantly increased with the UV irradiation time, because of amount of microfiber dropping, the entanglement of molecular segments on the non-crystalline decreasing, and the difficulty degree of craze microfiber fracture reducing.After aging for over 504 hours, aged layer can be observed on specimens’ surface, meanwhile, polymer brittleness increased, tensile strength had no significant change, elongation at break declined 29.53%, and Shore hardness value increased 6.9%. SPT performed more susceptibly on aged HDPE, and the maximum load dropped more than 39%. This illustrated that SPT is more suitable for the assessment to aged HDPE, which could more focus on aged layer.

Abstract: To evaluate the aging behavior of high density polyethylene (HDPE) under an artificial accelerated environment, principal component analysis (PCA) was used to establish a non-dimensional expression Z from a data set of multiple degradation parameters of HDPE. In this study, HDPE samples were exposed to the accelerated thermal oxidative environment for different time intervals up to 64 days. The results showed that the combined evaluating parameter Z was characterized by three-stage changes. The combined evaluating parameter Z increased quickly in the first 16 days of exposure and then leveled off. After 40 days, it began to increase again. Among the 10 degradation parameters, branching degree, carbonyl index and hydroxyl index are strongly associated. The tensile modulus is highly correlated with the impact strength. The tensile strength, tensile modulus and impact strength are negatively correlated with the crystallinity.

Abstract: In recent years, Wood Plastic Composite (WPC) has found widespread applications in the field of construction, decoration and furniture. In this work, the effect of weathering on the mechanical properties of WPC made from high density polyethylene (HDPE) and rice straw particles (RS) has been studied. Different loading of composite (20, 35 and 50% RS) were tested. Polyethylene wax (PE-wax) and UV-stabilizer were also added to assess their effect on the WPC composite.

Abstract: In the present study, we attempt to use powder of glass spheres filler and reinforce material in HDPE to produce composite structure and then evaluate its mechanical properties to study the effect of welding parameters and filler content on mechanical properties of HDPE. The effect of welding parameters (tool rotational speed, the plunge depth and the dwell time) on friction stir spot welding properties of high density polyethylene/glass spheres (hollow) polymer composites sheets was studied.

Abstract: This paper aims to highlight the study of polymeric composite responsible development with the environment and with the growth of the recycling of materials, from the use of high density polyethylene (HDPE) with eucalyptus wood dust from the furniture manufacturing. The study started from a literature search where they were analyzed the factors involving the subject in question, highlighting the concept of polymer, synthetic fibers, wood powder presence, composites to identify and understand the problem in issue. The study was developed from mechanical, morphological and rheological testing of composites with concentrations of 0, 5, 10 and 20% wood in relation to the polymer matrix in order to characterize and compare the obtained materials. Based on this context, this study was developed based on material supplied by a sawmill, where we used wood dust to perform the necessary tests and experiments, thus aiming to analyze the possibility front the production of HDPE composite from the use of different fractions.

Abstract: The compatibilizer effect of ENR-50 on the tensile properties of high density polyethylene (HDPE)/recycled acrylonitrile butadiene rubber (NBRr)/banana skin powder (BSP)/ composites has been studies. HDPE/NBRr/BSP composites were prepared by melt mixing technique using twin-screw at 180 °C for 9 minutes at rotor speed 50 rpm. The six different composites studied were 100/0/5, 80/20/5, 70/30/5, 60/40/5, 50/50/5, and 40/60/5. As for compatibilized composite a fix 5 wt% of ENR-50 was evaluated. The specimens were analysed for tensile strength and elongation at break (E_b). The results showed that tensile strength and the elongation at break were decreases with the increasing of NBRr loading. However for ENR-50 compatibilized composites, higher tensile strength and elongation at break was recorded. The ENR-50 was found to be an excellent compatibilizer for HDPE/NBRr/BSP composites.

Abstract: The thermal degradation of high density polyethylene (HDPE)/ recycled acrylonitrile butadiene rubber (NBRr)/ banana skin powder (BSP) composites with and without ENR-50 are fabricated and studied. The thermal degradation of this composite was evaluated for 30 days oven ageing. The BSP with size of 150 – 300 μm was utilized in this work. All compounds were mixed using heated two roll mill at 180 °C. The compounds were molded in a hot press machine at 180 °C for 11 minutes to produce 1 mm thin sheet. Then the sheet were cut into dumbbell shape for the mechanical testing using universal testing machine. The tensile strength of high density polyethylene/ recycled acrylonitrile butadiene rubber/ banana skin powder composites showed the decreasing trend with the increasing NBRr loading for the composites with and without ENR-50. However, the result for the oven ageing showed lower tensile strength. This may due to the chain session of PP matrix at heat exposure duration of 30 days.

Abstract: In this study, high density polyethylene (HDPE) is reinforced by the combination of clay to form HDPE/clay composites by applying maleic anhydride grafted polyethylene (PE-g-MA) as a compatibilizer and a melt compounding method. The properties of composites are evaluated with a tensile strength test, a scanning electron microscope (SEM), and a differential scanning calorimetry (DSC). Next, such composites are laminated with glass fiber woven fabrics (GFW) to form HDPE/clay/GFW composites by using a thermal compression molding method. A tensile strength test and an SEM are used to measure the properties of the HDPE/clay/GFW composites. The test results show that the combination of clay in HDPE/clay composites does not provide their tensile strength with a distinct reinforcement. However, the dispersion of clay promotes the crystallization temperature of the HDPE/clay composites. In addition, using PE-g-MA as the compatibilizer results in a good adhesion of HDPE/clay composites to GFW, which in turn augments the tensile strength of the HDPE/clay/GFW composites.