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Han-seung Yang - One of the best experts on this subject based on the ideXlab platform.
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viscoelastic and thermal analysis of Lignocellulosic Material filled polypropylene bio composites
Journal of Thermal Analysis and Calorimetry, 2009Co-Authors: Han-seung Yang, Douglas J GardnerAbstract:In this study, we investigated the viscoelastic and thermal properties of Lignocellulosic Material filled polypropylene (PP) bio-composites. Lignocellulosic fillers are totally bio-degradable and PP is a thermoplastic polymer which has good stiffness, tenacity, flexural strength and thermal properties. The thermal and viscoelastic properties of the composites with different filler contents were examined using differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA), respectively. The effects of the compatibilizing agent were also evaluated. The glass transition (T g ) and melting (T m ) temperatures of the composites did not vary significantly with the filler content, because no chemical bonding occurred at the interface between the matrix and filler. However, the compatibility between the filler and PP matrix was increased by the incorporation of the compatibilizing agent. The storage modulus (E′) of the composites was higher than that of the neat PP, indicating that the incorporation of the natural filler increased their stiffness. The thermal properties of the composites should be considered as an important factor in the manufacturing process and the use of the final products.
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effect of different compatibilizing agents on the mechanical properties of Lignocellulosic Material filled polyethylene bio composites
Composite Structures, 2007Co-Authors: Han-seung Yang, Michael P. WolcottAbstract:The tensile and Izod impact strength properties of Lignocellulosic filler reinforced polyethylene bio-composites, made using low- and high-density polyethylene as the matrix polymer, rice-husk flour and wood flour as the reinforcing filler and different compatibilizing agents, were examined by assessing their mechanical properties and the morphological characteristics of their fracture surfaces. Test samples made with two different compatibilizing agents were injection molded, in order to determine their mechanical and morphological properties. The tensile strengths of the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were superior to those of the bio-composites fabricated using maleated polypropylene, due to the improved wetting of the former compatibilizing agent in the matrix polymer. Based on the results of the Izod impact strength tests, the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were also toughened. The SEM micrographs revealed a certain number of pulled-out traces on the fracture surfaces of the test samples fabricated using maleated polypropylene as the compatibilizing agent, but no pulled-out traces and many broken fillers on the fracture surfaces of the test samples fabricated using maleated polyethylene as the compatibilizing agent, due to the stronger interfacial bonding.
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Effect of different compatibilizing agents on the mechanical properties of Lignocellulosic Material filled polyethylene bio-composites
Composite Structures, 2007Co-Authors: Han-seung Yang, Sumin Kim, Hee Soo Kim, Michael P. Wolcott, Hyun-joong KimAbstract:The tensile and Izod impact strength properties of Lignocellulosic filler reinforced polyethylene bio-composites, made using low- and high-density polyethylene as the matrix polymer, rice-husk flour and wood flour as the reinforcing filler and different compatibilizing agents, were examined by assessing their mechanical properties and the morphological characteristics of their fracture surfaces. Test samples made with two different compatibilizing agents were injection molded, in order to determine their mechanical and morphological properties. The tensile strengths of the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were superior to those of the bio-composites fabricated using maleated polypropylene, due to the improved wetting of the former compatibilizing agent in the matrix polymer. Based on the results of the Izod impact strength tests, the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were also toughened. The SEM micrographs revealed a certain number of pulled-out traces on the fracture surfaces of the test samples fabricated using maleated polypropylene as the compatibilizing agent, but no pulled-out traces and many broken fillers on the fracture surfaces of the test samples fabricated using maleated polyethylene as the compatibilizing agent, due to the stronger interfacial bonding. © 2006 Elsevier Ltd. All rights reserved.
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properties of Lignocellulosic Material filled polypropylene bio composites made with different manufacturing processes
Polymer Testing, 2006Co-Authors: Han-seung Yang, Michael P. WolcottAbstract:Using polypropylene as the matrix polymer and rice-husk flour and wood flour as the reinforcing filler, the tensile and Izod impact properties of Lignocellulosic filler reinforced polypropylene bio-composites made with different extruding systems were examined by assessing their mechanical properties and the morphology of the fracture surfaces. The test samples were injection molded, in order to determine the mechanical and morphological properties of the bio-composites made with two different extruding systems and at different filler loadings. The tensile strength and modulus of the bio-composites fabricated using the twin-screw extruding system were improved as compared with those fabricated using the single-screw extruding system, due to the improved dispersion of the fillers in the composite. There was no difference in the Izod impact strength of the composites fabricated using the twin-screw and single-screw extruding systems, the similar impact strength of both samples with different extruding processes might be due to the fact that impact test is not discriminating enough to reveal the difference in dispersion status of the present composites. The SEM micrographs revealed well-dispersed fillers on the fracture surfaces of the test samples fabricated using a twin-screw extruding system.
Michael P. Wolcott - One of the best experts on this subject based on the ideXlab platform.
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effect of different compatibilizing agents on the mechanical properties of Lignocellulosic Material filled polyethylene bio composites
Composite Structures, 2007Co-Authors: Han-seung Yang, Michael P. WolcottAbstract:The tensile and Izod impact strength properties of Lignocellulosic filler reinforced polyethylene bio-composites, made using low- and high-density polyethylene as the matrix polymer, rice-husk flour and wood flour as the reinforcing filler and different compatibilizing agents, were examined by assessing their mechanical properties and the morphological characteristics of their fracture surfaces. Test samples made with two different compatibilizing agents were injection molded, in order to determine their mechanical and morphological properties. The tensile strengths of the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were superior to those of the bio-composites fabricated using maleated polypropylene, due to the improved wetting of the former compatibilizing agent in the matrix polymer. Based on the results of the Izod impact strength tests, the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were also toughened. The SEM micrographs revealed a certain number of pulled-out traces on the fracture surfaces of the test samples fabricated using maleated polypropylene as the compatibilizing agent, but no pulled-out traces and many broken fillers on the fracture surfaces of the test samples fabricated using maleated polyethylene as the compatibilizing agent, due to the stronger interfacial bonding.
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Effect of different compatibilizing agents on the mechanical properties of Lignocellulosic Material filled polyethylene bio-composites
Composite Structures, 2007Co-Authors: Han-seung Yang, Sumin Kim, Hee Soo Kim, Michael P. Wolcott, Hyun-joong KimAbstract:The tensile and Izod impact strength properties of Lignocellulosic filler reinforced polyethylene bio-composites, made using low- and high-density polyethylene as the matrix polymer, rice-husk flour and wood flour as the reinforcing filler and different compatibilizing agents, were examined by assessing their mechanical properties and the morphological characteristics of their fracture surfaces. Test samples made with two different compatibilizing agents were injection molded, in order to determine their mechanical and morphological properties. The tensile strengths of the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were superior to those of the bio-composites fabricated using maleated polypropylene, due to the improved wetting of the former compatibilizing agent in the matrix polymer. Based on the results of the Izod impact strength tests, the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were also toughened. The SEM micrographs revealed a certain number of pulled-out traces on the fracture surfaces of the test samples fabricated using maleated polypropylene as the compatibilizing agent, but no pulled-out traces and many broken fillers on the fracture surfaces of the test samples fabricated using maleated polyethylene as the compatibilizing agent, due to the stronger interfacial bonding. © 2006 Elsevier Ltd. All rights reserved.
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properties of Lignocellulosic Material filled polypropylene bio composites made with different manufacturing processes
Polymer Testing, 2006Co-Authors: Han-seung Yang, Michael P. WolcottAbstract:Using polypropylene as the matrix polymer and rice-husk flour and wood flour as the reinforcing filler, the tensile and Izod impact properties of Lignocellulosic filler reinforced polypropylene bio-composites made with different extruding systems were examined by assessing their mechanical properties and the morphology of the fracture surfaces. The test samples were injection molded, in order to determine the mechanical and morphological properties of the bio-composites made with two different extruding systems and at different filler loadings. The tensile strength and modulus of the bio-composites fabricated using the twin-screw extruding system were improved as compared with those fabricated using the single-screw extruding system, due to the improved dispersion of the fillers in the composite. There was no difference in the Izod impact strength of the composites fabricated using the twin-screw and single-screw extruding systems, the similar impact strength of both samples with different extruding processes might be due to the fact that impact test is not discriminating enough to reveal the difference in dispersion status of the present composites. The SEM micrographs revealed well-dispersed fillers on the fracture surfaces of the test samples fabricated using a twin-screw extruding system.
Douglas J Gardner - One of the best experts on this subject based on the ideXlab platform.
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viscoelastic and thermal analysis of Lignocellulosic Material filled polypropylene bio composites
Journal of Thermal Analysis and Calorimetry, 2009Co-Authors: Han-seung Yang, Douglas J GardnerAbstract:In this study, we investigated the viscoelastic and thermal properties of Lignocellulosic Material filled polypropylene (PP) bio-composites. Lignocellulosic fillers are totally bio-degradable and PP is a thermoplastic polymer which has good stiffness, tenacity, flexural strength and thermal properties. The thermal and viscoelastic properties of the composites with different filler contents were examined using differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA), respectively. The effects of the compatibilizing agent were also evaluated. The glass transition (T g ) and melting (T m ) temperatures of the composites did not vary significantly with the filler content, because no chemical bonding occurred at the interface between the matrix and filler. However, the compatibility between the filler and PP matrix was increased by the incorporation of the compatibilizing agent. The storage modulus (E′) of the composites was higher than that of the neat PP, indicating that the incorporation of the natural filler increased their stiffness. The thermal properties of the composites should be considered as an important factor in the manufacturing process and the use of the final products.
Jianxiao Yang - One of the best experts on this subject based on the ideXlab platform.
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effects of the heating history of impregnated Lignocellulosic Material on pore development during phosphoric acid activation
Carbon, 2010Co-Authors: Jianxiao YangAbstract:Activated carbon samples have been prepared by heating China fir (Cunninghamia lanceolata) wood impregnated with phosphoric acid in an effort to elucidate the effect of the heating history of impregnated Material on the porous texture of the activated carbon. Analysis of the pore structure of the activated carbon in terms of nitrogen adsorption isotherms showed that both using an intermediate isothermal treatment and slowing the heating rate up to 300 °C favor pore development but have a detrimental effect above 300 °C. Therefore, it is recommended that a two-step heating program is applied for phosphoric acid activation.
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effects of the crystallinity of Lignocellulosic Material on the porosity of phosphoric acid activated carbon
Carbon, 2009Co-Authors: Jianxiao YangAbstract:Activated carbons were prepared from three different Lignocellulosic Materials or in various lengths of impregnation time by phosphoric acid activation. The porous texture of activated carbon was analyzed in terms of the adsorption isotherm of nitrogen, and the crystallinity of Lignocellulosic Material was measured by X-ray diffraction method. The results showed that decreasing the crystallinity of Lignocellulosic Material promotes pore development, especially of mesopores. However, excessive impregnation is detrimental to activation. Impregnation and the selection of parent Lignocellulosic Material have a similar effect on developing porosity during phosphoric acid activation.
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significance of the carbonization of volatile pyrolytic products on the properties of activated carbons from phosphoric acid activation of Lignocellulosic Material
Fuel Processing Technology, 2009Co-Authors: Jianxiao YangAbstract:Abstract Two series of activated carbons derived from China fir (Cunninghamia lanceolata) wood impregnated with phosphoric acid were prepared in a cylindrical container that was kept in a closed state covered with a lid (the covered case) or in an open state. The effects of the carbonization of volatile pyrolytic products of starting Materials on the properties of activated carbon were investigated in the process of phosphoric acid activation. Elemental analysis and SEM observation showed that both activating in the covered case and increasing the mass of starting Material used favored the carbonization of volatile pyrolytic products. An investigation of N2 adsorption isotherms revealed that the carbonization of volatile pyrolytic products significantly enhanced mesopore development in the final carbons, especially pores with a size range from 2.5 to 30 nm, with little influence on micropores, and therefore produced a large increase in the adsorption capacity to Vitamin B12 (with a molecular size of 2.09 nm). Activated carbons with highly developed mesopores could be obtained in the covered case. The carbonization mechanism of volatiles was discussed and two different carbonization pathways (in solid and gas phases) were proposed during phosphoric acid activation.
Hyun-joong Kim - One of the best experts on this subject based on the ideXlab platform.
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Effect of different compatibilizing agents on the mechanical properties of Lignocellulosic Material filled polyethylene bio-composites
Composite Structures, 2007Co-Authors: Han-seung Yang, Sumin Kim, Hee Soo Kim, Michael P. Wolcott, Hyun-joong KimAbstract:The tensile and Izod impact strength properties of Lignocellulosic filler reinforced polyethylene bio-composites, made using low- and high-density polyethylene as the matrix polymer, rice-husk flour and wood flour as the reinforcing filler and different compatibilizing agents, were examined by assessing their mechanical properties and the morphological characteristics of their fracture surfaces. Test samples made with two different compatibilizing agents were injection molded, in order to determine their mechanical and morphological properties. The tensile strengths of the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were superior to those of the bio-composites fabricated using maleated polypropylene, due to the improved wetting of the former compatibilizing agent in the matrix polymer. Based on the results of the Izod impact strength tests, the bio-composites fabricated using maleated polyethylene as the compatibilizing agent were also toughened. The SEM micrographs revealed a certain number of pulled-out traces on the fracture surfaces of the test samples fabricated using maleated polypropylene as the compatibilizing agent, but no pulled-out traces and many broken fillers on the fracture surfaces of the test samples fabricated using maleated polyethylene as the compatibilizing agent, due to the stronger interfacial bonding. © 2006 Elsevier Ltd. All rights reserved.