The Experts below are selected from a list of 2601 Experts worldwide ranked by ideXlab platform
M D Ediger - One of the best experts on this subject based on the ideXlab platform.
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vapor deposited glass structure determined by deposition rate substrate Temperature Superposition Principle
Journal of Physical Chemistry Letters, 2019Co-Authors: Camille Bishop, Ankit Gujral, Michael F Toney, Lian Yu, M D EdigerAbstract:We show that deposition rate substantially affects the anisotropic structure of thin glassy films produced by physical vapor deposition. Itraconazole, a glass-forming liquid crystal, was deposited ...
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vapor deposited glass structure determined by deposition rate substrate Temperature Superposition Principle
Journal of Physical Chemistry Letters, 2019Co-Authors: Camille Bishop, Ankit Gujral, Michael F Toney, M D EdigerAbstract:We show that deposition rate substantially affects the anisotropic structure of thin glassy films produced by physical vapor deposition. Itraconazole, a glass-forming liquid crystal, was deposited at rates spanning 3 orders of magnitude over a 25 K range of substrate Temperatures, and structure was characterized by ellipsometry and X-ray scattering. Both the molecular orientation and the spacing of the smectic layers obey deposition rate-substrate Temperature Superposition, such that lowering the deposition rate is equivalent to raising the substrate Temperature. We identify two different surface relaxations that are responsible for structural order in the vapor-deposited glasses and find that the process controlling molecular orientation is accelerated by more than 3 orders of magnitude at the surface relative to the bulk. The identification of distinct surface processes responsible for anisotropic structural features in vapor-deposited glasses will enable more precise control over the structure of glassy materials used in organic electronics.
Edith Peuvreldisdier - One of the best experts on this subject based on the ideXlab platform.
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time evolution of the structure of organoclay polypropylene nanocomposites and application of the time Temperature Superposition Principle
Journal of Rheology, 2012Co-Authors: Riadh Zouari, Trystan Domenech, Bruno Vergnes, Edith PeuvreldisdierAbstract:We investigated the rheological properties of nanocomposites composed of polypropylene, organoclay, and maleic anhydride grafted polypropylene in small amplitude oscillatory shear. Samples were prepared in two steps: a masterbatch was first obtained by melt extrusion and then diluted into polypropylene using an internal mixer. Three formulations were investigated. The measurement of the storage and loss moduli evolution with time showed that these materials were not stable: the nanostructure obtained after steady shear continuously changed with time, due to the disorientation of the clay platelets and the build-up of a 3D network. The kinetics of the structure build-up (followed via the melt yield stress) showed a two-step process. This feature was found to be valid whatever the nanocomposite formulation. Such evolution of the structure is generally assumed to violate the time–Temperature Superposition Principle. We demonstrate in this paper that the time–Temperature equivalence always exists if the same nanostructure is probed. This was achieved by using different annealing times for different Temperatures or annealing the samples at the highest Temperature before measuring at lower values. The time–Temperature equivalence evidences that the Temperature does not induce any chemical change within the material, whose properties remain governed by the same physical phenomena.
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time evolution of the structure of organoclay polypropylene nanocomposites and application of the time Temperature Superposition Principle
Journal of Rheology, 2012Co-Authors: Riadh Zouari, Trystan Domenech, Bruno Vergnes, Edith PeuvreldisdierAbstract:We investigated the rheological properties of nanocomposites composed of polypropylene, organoclay, and maleic anhydride grafted polypropylene in small amplitude oscillatory shear. Samples were prepared in two steps: a masterbatch was first obtained by melt extrusion and then diluted into polypropylene using an internal mixer. Three formulations were investigated. The measurement of the storage and loss moduli evolution with time showed that these materials were not stable: the nanostructure obtained after steady shear continuously changed with time, due to the disorientation of the clay platelets and the build-up of a 3D network. The kinetics of the structure build-up (followed via the melt yield stress) showed a two-step process. This feature was found to be valid whatever the nanocomposite formulation. Such evolution of the structure is generally assumed to violate the time–Temperature Superposition Principle. We demonstrate in this paper that the time–Temperature equivalence always exists if the same ...
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time evolution of the structure of organoclay polypropylene nanocomposites and its influence on time Temperature Superposition Principle
27th World Congress of the Polymer Processing Society, 2011Co-Authors: Riadh Zouari, Trystan Domenech, Edith Peuvreldisdier, Bruno VergnesAbstract:We investigate the rheological properties of a nanocomposite in small amplitude oscillatory shear. The evolution of the storage modulus with time shows that this material is not stable: the microstructure changes continuously with time, due to the disorientation of the clay platelets and the build-up of a 3D network. This evolution of the microstructure is evaluated by measuring the apparent yield stress. A two-step kinetics is evidenced, whose parameters directly depends on Temperature. This time-evolution is generally assumed to violate the time-Temperature Superposition Principle. However, we demonstrate that the time-Temperature equivalence always exists if we consider samples having the same microstructure.
Camille Bishop - One of the best experts on this subject based on the ideXlab platform.
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vapor deposited glass structure determined by deposition rate substrate Temperature Superposition Principle
Journal of Physical Chemistry Letters, 2019Co-Authors: Camille Bishop, Ankit Gujral, Michael F Toney, Lian Yu, M D EdigerAbstract:We show that deposition rate substantially affects the anisotropic structure of thin glassy films produced by physical vapor deposition. Itraconazole, a glass-forming liquid crystal, was deposited ...
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vapor deposited glass structure determined by deposition rate substrate Temperature Superposition Principle
Journal of Physical Chemistry Letters, 2019Co-Authors: Camille Bishop, Ankit Gujral, Michael F Toney, M D EdigerAbstract:We show that deposition rate substantially affects the anisotropic structure of thin glassy films produced by physical vapor deposition. Itraconazole, a glass-forming liquid crystal, was deposited at rates spanning 3 orders of magnitude over a 25 K range of substrate Temperatures, and structure was characterized by ellipsometry and X-ray scattering. Both the molecular orientation and the spacing of the smectic layers obey deposition rate-substrate Temperature Superposition, such that lowering the deposition rate is equivalent to raising the substrate Temperature. We identify two different surface relaxations that are responsible for structural order in the vapor-deposited glasses and find that the process controlling molecular orientation is accelerated by more than 3 orders of magnitude at the surface relative to the bulk. The identification of distinct surface processes responsible for anisotropic structural features in vapor-deposited glasses will enable more precise control over the structure of glassy materials used in organic electronics.
Riadh Zouari - One of the best experts on this subject based on the ideXlab platform.
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time evolution of the structure of organoclay polypropylene nanocomposites and application of the time Temperature Superposition Principle
Journal of Rheology, 2012Co-Authors: Riadh Zouari, Trystan Domenech, Bruno Vergnes, Edith PeuvreldisdierAbstract:We investigated the rheological properties of nanocomposites composed of polypropylene, organoclay, and maleic anhydride grafted polypropylene in small amplitude oscillatory shear. Samples were prepared in two steps: a masterbatch was first obtained by melt extrusion and then diluted into polypropylene using an internal mixer. Three formulations were investigated. The measurement of the storage and loss moduli evolution with time showed that these materials were not stable: the nanostructure obtained after steady shear continuously changed with time, due to the disorientation of the clay platelets and the build-up of a 3D network. The kinetics of the structure build-up (followed via the melt yield stress) showed a two-step process. This feature was found to be valid whatever the nanocomposite formulation. Such evolution of the structure is generally assumed to violate the time–Temperature Superposition Principle. We demonstrate in this paper that the time–Temperature equivalence always exists if the same nanostructure is probed. This was achieved by using different annealing times for different Temperatures or annealing the samples at the highest Temperature before measuring at lower values. The time–Temperature equivalence evidences that the Temperature does not induce any chemical change within the material, whose properties remain governed by the same physical phenomena.
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time evolution of the structure of organoclay polypropylene nanocomposites and application of the time Temperature Superposition Principle
Journal of Rheology, 2012Co-Authors: Riadh Zouari, Trystan Domenech, Bruno Vergnes, Edith PeuvreldisdierAbstract:We investigated the rheological properties of nanocomposites composed of polypropylene, organoclay, and maleic anhydride grafted polypropylene in small amplitude oscillatory shear. Samples were prepared in two steps: a masterbatch was first obtained by melt extrusion and then diluted into polypropylene using an internal mixer. Three formulations were investigated. The measurement of the storage and loss moduli evolution with time showed that these materials were not stable: the nanostructure obtained after steady shear continuously changed with time, due to the disorientation of the clay platelets and the build-up of a 3D network. The kinetics of the structure build-up (followed via the melt yield stress) showed a two-step process. This feature was found to be valid whatever the nanocomposite formulation. Such evolution of the structure is generally assumed to violate the time–Temperature Superposition Principle. We demonstrate in this paper that the time–Temperature equivalence always exists if the same ...
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time evolution of the structure of organoclay polypropylene nanocomposites and its influence on time Temperature Superposition Principle
27th World Congress of the Polymer Processing Society, 2011Co-Authors: Riadh Zouari, Trystan Domenech, Edith Peuvreldisdier, Bruno VergnesAbstract:We investigate the rheological properties of a nanocomposite in small amplitude oscillatory shear. The evolution of the storage modulus with time shows that this material is not stable: the microstructure changes continuously with time, due to the disorientation of the clay platelets and the build-up of a 3D network. This evolution of the microstructure is evaluated by measuring the apparent yield stress. A two-step kinetics is evidenced, whose parameters directly depends on Temperature. This time-evolution is generally assumed to violate the time-Temperature Superposition Principle. However, we demonstrate that the time-Temperature equivalence always exists if we consider samples having the same microstructure.
Kechang Hung - One of the best experts on this subject based on the ideXlab platform.
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effects of heat treated wood particles on the physico mechanical properties and extended creep behavior of wood recycled hdpe composites using the time Temperature Superposition Principle
Materials, 2017Co-Authors: Tengchun Yang, Yichi Chien, Kechang HungAbstract:This study investigated the effectiveness of heat-treated wood particles for improving the physico-mechanical properties and creep performance of wood/recycled-HDPE composites. The results reveal that the composites with heat-treated wood particles had significantly decreased moisture content, water absorption, and thickness swelling, while no improvements of the flexural properties or the wood screw holding strength were observed, except for the internal bond strength. Additionally, creep tests were conducted at a series of elevated Temperatures using the time–Temperature Superposition Principle (TTSP), and the TTSP-predicted creep compliance curves fit well with the experimental data. The creep resistance values of composites with heat-treated wood particles were greater than those having untreated wood particles due to the hydrophobic character of the treated wood particles and improved interfacial compatibility between the wood particles and polymer matrix. At a reference Temperature of 20 °C, the improvement of creep resistance (ICR) of composites with heat-treated wood particles reached approximately 30% over a 30-year period, and it increased significantly with increasing reference Temperature.
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assessing the effect of wood acetylation on mechanical properties and extended creep behavior of wood recycled polypropylene composites
Construction and Building Materials, 2016Co-Authors: Kechang Hung, Yonglong Chen, Tunglin Wu, Jyhhorng WuAbstract:Abstract This study investigates the effect of wood acetylation on the mechanical properties and creep resistance of wood/recycled-polypropylene composites (WRPCs) using the time–Temperature Superposition Principle (TTSP). The results revealed that the flexural and tensile strength of WRPCs increased with increasing weight percent gain (WPG) of acetylated wood particles up to 13%. Additionally, the TTSP-predicted creep compliance curve fit well with the long-term experimental data. The creep resistance of WRPCs with acetylated wood particles was greater than that of WRPCs with unmodified wood particles, especially for the WRPC with 13% WPG of acetylated wood particles.
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mechanical properties and extended creep behavior of bamboo fiber reinforced recycled poly lactic acid composites using the time Temperature Superposition Principle
Construction and Building Materials, 2015Co-Authors: Tengchun Yang, Kechang Hung, Yonglong ChenAbstract:Abstract The present study investigates mechanical properties and creep resistance of bamboo fiber reinforced recycled PLA composites (BFRPCs). The results revealed that the modulus of rupture and modulus of elasticity of BFRPCs increased with increasing bamboo fiber loading up to 60 wt% and then declined sharply as the fiber increased further. Short-term accelerated creep tests on BFRPCs were conducted at a series of elevated Temperatures by time–Temperature Superposition Principle. As a result, the BFRPC with 60 wt% fiber exhibited the best creep resistance among all the BFRPCs, and then decreased when the fiber loading was more than 70 wt%.
