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High density polyethylene (HDPE) has been used extensively in many sectors of the industry. The main reason for the frequent use of HDPE is its low cost, easy processing, and high performance. These sectors include household and garden products, packaging etc. In order to reduce the production cost of plastic products and to improve plastic's moldability and stability, one or more minerals are usually filled into the thermoplastics. The minerals commonly used as fillers in plastic molding compounds include calcium carbonate, talc, silica, wollastonite, clay, mica, glass beads, and alumina trihydrate. In this paper, diatomite (DA) filled HDPE composites were prepared with gelimat mixer and hot press molding technique. Thermal properties of the composites were studied by thermogravimetric analysis and dynamic mechanical analysis. The mechanical properties of the composites were determined by using universal testing machine. Morphology of the composites was investigated by scanning electron microscopy. With the addition of DA into HDPE, significant change in tensile and flexural strengths of HDPE was not observed. The loss and storage moduli increased with increasing weight fraction of DA. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop composites with high thermal conductivity by employing the thermophysical properties of aluminum nitride (AlN), hexagonal boron nitride (hBN), and synthetic graphite (SG). AlN, hBN, and SG filled polyamide 6 (PA) composites were prepared using a co-rotating twin-screw extruder and injection molding. Changes in thermal, mechanical, and electrical properties of the composites were investigated. The highest in-plane and through-plane thermal conductivity values were obtained with 50 wt.% SG and 50 wt.% AlN loadings, respectively. Mechanical strength of PA decreased for all filler loadings. Electrical conductivity results showed that AlN and hBN filled PA composites behave as electrical insulators. On the contrary, SG loading led to electrically conductive PA composites. [ABSTRACT FROM AUTHOR]

Over the last decades, automotive industries have investigated a variety of technological developments and design strategies. The reduction of vehicle weight has been proved to be a particularly effective way to meet automobile performance requirements in the areas of fuel economy and emissions. One major option in the vehicle weight reduction strategy is the use of lightweight materials, namely the carbon fiber reinforced polymers. However, poor adhesion between carbon fibers and polymer matrix could be an important issue for carbon fiber reinforced polymers. In this study, in order to increase interfacial bonding between carbon fibers and the polymer matrix, maleic anhydride grafted polypropylene at different weight contents was used as a compatibilizer for better polymer/fiber interpenetration. Recycled chopped carbon fiber reinforced polypropylene composites with maleic anhydride grafted polypropylene were prepared with high speed thermo kinetic mixing and hot press molding techniques. Thermal properties of the composites were studied by thermal gravimetric analysis and differential scanning calorimety. Morphology of the composites was observed by scanning electron microscopy. The tensile properties of these composites were investigated. Tensile strength values of recycled chopped carbon fiber reinforced polypropylene based composites increased with increasing compatibilizer content. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate mechanical and thermal properties of linear low density polyethylene (LLDPE)-based composite prepared with different almond shells powder (AS) contents. In this paper, AS (5, 10, 20, 30, and 40 wt%) filled LLDPE composites were prepared by compounding polyethylene and AS using a corotating twin screw extruder. All specimens for mechanical tests were molded using injection molding. 40 wt% AS filling into LLDPE has led to 100% increase in flexural strength of LLDPE. AS filling into LLDPE decreased the MFI value of LLDPE. AS filling into LLDPE at low weight fractions (5 and 10%) has not affected the un-notched impact strength of LLDPE. Thermal properties of the composite were studied by thermal gravimetric analysis (TGA). From TGA analysis, it is seen that degradation of AS within LLDPE started at about 200 °C [ABSTRACT FROM AUTHOR]

Abstract: The surfaces of jute fabrics have been oxygen plasma treated using low frequency (LF) and radio frequency (RF) plasma systems at different plasma powers (30, 60, and 90W) for 15min to improve the mechanical properties of jute fiber/HDPE (high density polyethylene) composites. The effect of oxygen plasma treatment on the functional groups of jute fibers was examined by X-ray photoelectron spectroscopy (XPS) analysis. Effects of oxygen plasma treatments on the mechanical properties of jute fiber/HDPE composites were investigated by means of tensile, flexure, and short-beam shear tests. Surface morphology of the fractured surfaces of composites was observed by using scanning electron microscopy (SEM). When RF plasma system was used, the interlaminar shear strength (ILSS) values of the composites increased with increasing plasma power. Similarly, in LF plasma system, ILSS values showed a tendency to increase at plasma powers of 30 and 60W. However, increasing of plasma power to 90W decreased the ILSS value of jute/HDPE composite. Also, tensile and flexure strengths of the composites showed similar trends. [Copyright &y& Elsevier]

The aim of this study is to investigate the filling properties of an agricultural waste, olive pomace powder (OP), for polypropylene (PP) matrix material. Different weight fractions of OP (from 10 to 40 wt %), which has a median particle size of 21.36 μm (D50) μm, were loaded into PP by high-speed thermo kinetic mixer. In this research, the effects of weight fraction of OP within PP on mechanical, viscoelastic, thermal, chemical, crystallographic, and morphological properties of PP composites were investigated by tensile and three point bending test, dynamic mechanic analysis, thermogravimetric analysis and differential scanning calorimetry, Fourier transform infrared analysis, X-ray diffraction analysis, and scanning electron microscopy. When 40 wt% OP filler was loaded into PP, the Young's modulus and flexural modulus of PP increased by about 62.5% and 19%, respectively. The storage modulus and thermal stability of PP were remarkably enhanced with increasing OP weight fraction. [ABSTRACT FROM AUTHOR]