The Experts below are selected from a list of 24 Experts worldwide ranked by ideXlab platform
K I Zamaraev - One of the best experts on this subject based on the ideXlab platform.
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Intrinsic microporosity and gas transport in Polyphenylene oxide polymers
Microporous and Mesoporous Materials, 1999Co-Authors: O M Ilinitch, A A Lapkin, V. B. Fenelonov, L. G. Okkel, V.v. Terskikh, K I ZamaraevAbstract:Abstract Glassy polymers of the Polyphenylene oxide series (PPOs) were investigated using the low-temperature nitrogen adsorption and 129 Xe NMR spectroscopy techniques. The experimental data are indicative of a developed system of interconnected microcavities existing in the polymers. The intrinsic microporosity of PPOs is most probably formed by a continuous three-dimensional network of molecular-sized interstices between the rigid-chain macromolecules. These supposedly constitute the free volume of the polymers. The micropores are likely to be of the ‘throat and cavity’ type, where a cavity may possess several throats. Effective diameters of the throats were estimated to be approximately 0.4 nm at 77 K. It is believed that transport of gas molecules occurs through these micropores. Variations in gas permeability and sorption characteristics, which are dependent on the previous history of the polymer, were investigated and interrelations between these features analyzed. Crystallinity vs. gas permeability relationships for PPO membranes were studied. It is concluded that crystalline and amorphous phases of Polyphenylene Oxides have similar gas permeabilities for the experimental conditions employed. Analysis of the experimental data shows that it is justified to look upon Polyphenylene Oxides as polymeric analogues of solid microporous adsorbents.
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propylene in Polyphenylene Oxides membranes unusual permeability vs pressure behaviour
Journal of Membrane Science, 1995Co-Authors: O M Ilinitch, A A Lapkin, K I ZamaraevAbstract:Abstract The dependencies of propylene permeability coefficients vs. pressure at 298 K in the films of glassy polymers-Polyphenylene Oxides, poly (amide imide) and poly (vinyltrimethylsilane) — exhibit a sharp multifold rise (“permeability crisis”) at ca. 0.45 MPa. The analogous dependence for the rubbery polyethylene is represented by the monotonously rising smooth curve. No “permeability crisis” was observed as well for the pressure-permeability dependencies of Ar, O 2 , N 2 , C 2 H 4 and C 2 H 6 in the Polyphenylene Oxides at pressures up to 1 MPa.
O M Ilinitch - One of the best experts on this subject based on the ideXlab platform.
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Intrinsic microporosity and gas transport in Polyphenylene oxide polymers
Microporous and Mesoporous Materials, 1999Co-Authors: O M Ilinitch, A A Lapkin, V. B. Fenelonov, L. G. Okkel, V.v. Terskikh, K I ZamaraevAbstract:Abstract Glassy polymers of the Polyphenylene oxide series (PPOs) were investigated using the low-temperature nitrogen adsorption and 129 Xe NMR spectroscopy techniques. The experimental data are indicative of a developed system of interconnected microcavities existing in the polymers. The intrinsic microporosity of PPOs is most probably formed by a continuous three-dimensional network of molecular-sized interstices between the rigid-chain macromolecules. These supposedly constitute the free volume of the polymers. The micropores are likely to be of the ‘throat and cavity’ type, where a cavity may possess several throats. Effective diameters of the throats were estimated to be approximately 0.4 nm at 77 K. It is believed that transport of gas molecules occurs through these micropores. Variations in gas permeability and sorption characteristics, which are dependent on the previous history of the polymer, were investigated and interrelations between these features analyzed. Crystallinity vs. gas permeability relationships for PPO membranes were studied. It is concluded that crystalline and amorphous phases of Polyphenylene Oxides have similar gas permeabilities for the experimental conditions employed. Analysis of the experimental data shows that it is justified to look upon Polyphenylene Oxides as polymeric analogues of solid microporous adsorbents.
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propylene in Polyphenylene Oxides membranes unusual permeability vs pressure behaviour
Journal of Membrane Science, 1995Co-Authors: O M Ilinitch, A A Lapkin, K I ZamaraevAbstract:Abstract The dependencies of propylene permeability coefficients vs. pressure at 298 K in the films of glassy polymers-Polyphenylene Oxides, poly (amide imide) and poly (vinyltrimethylsilane) — exhibit a sharp multifold rise (“permeability crisis”) at ca. 0.45 MPa. The analogous dependence for the rubbery polyethylene is represented by the monotonously rising smooth curve. No “permeability crisis” was observed as well for the pressure-permeability dependencies of Ar, O 2 , N 2 , C 2 H 4 and C 2 H 6 in the Polyphenylene Oxides at pressures up to 1 MPa.
A A Lapkin - One of the best experts on this subject based on the ideXlab platform.
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Intrinsic microporosity and gas transport in Polyphenylene oxide polymers
Microporous and Mesoporous Materials, 1999Co-Authors: O M Ilinitch, A A Lapkin, V. B. Fenelonov, L. G. Okkel, V.v. Terskikh, K I ZamaraevAbstract:Abstract Glassy polymers of the Polyphenylene oxide series (PPOs) were investigated using the low-temperature nitrogen adsorption and 129 Xe NMR spectroscopy techniques. The experimental data are indicative of a developed system of interconnected microcavities existing in the polymers. The intrinsic microporosity of PPOs is most probably formed by a continuous three-dimensional network of molecular-sized interstices between the rigid-chain macromolecules. These supposedly constitute the free volume of the polymers. The micropores are likely to be of the ‘throat and cavity’ type, where a cavity may possess several throats. Effective diameters of the throats were estimated to be approximately 0.4 nm at 77 K. It is believed that transport of gas molecules occurs through these micropores. Variations in gas permeability and sorption characteristics, which are dependent on the previous history of the polymer, were investigated and interrelations between these features analyzed. Crystallinity vs. gas permeability relationships for PPO membranes were studied. It is concluded that crystalline and amorphous phases of Polyphenylene Oxides have similar gas permeabilities for the experimental conditions employed. Analysis of the experimental data shows that it is justified to look upon Polyphenylene Oxides as polymeric analogues of solid microporous adsorbents.
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propylene in Polyphenylene Oxides membranes unusual permeability vs pressure behaviour
Journal of Membrane Science, 1995Co-Authors: O M Ilinitch, A A Lapkin, K I ZamaraevAbstract:Abstract The dependencies of propylene permeability coefficients vs. pressure at 298 K in the films of glassy polymers-Polyphenylene Oxides, poly (amide imide) and poly (vinyltrimethylsilane) — exhibit a sharp multifold rise (“permeability crisis”) at ca. 0.45 MPa. The analogous dependence for the rubbery polyethylene is represented by the monotonously rising smooth curve. No “permeability crisis” was observed as well for the pressure-permeability dependencies of Ar, O 2 , N 2 , C 2 H 4 and C 2 H 6 in the Polyphenylene Oxides at pressures up to 1 MPa.
Oleg M. Ilinich - One of the best experts on this subject based on the ideXlab platform.
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Gas Permeation Through the Films of Polyphenylene Oxides
Polyphenylene Oxide and Modified Polyphenylene Oxide Membranes, 2001Co-Authors: Oleg M. IlinichAbstract:The first and so far the best known representative of the family of Polyphenylene ethers — poly-2, 6-dimethyl-l, 4-phenylene oxide, commonly called poly (phenylene oxide) or PPO — is also the one most intensively studied with respect to the membrane gas separation. The first study of gas permeability through PPO membrane known to the author was published by Yasuda and Rosengren in 1970 [1]. At that time the glassy polymers were considered exclusively as the “barrier” materials. The researches were rewarded by the result of paramount importance: the permeabilities of gases through PPO were found to be unexpectedly high. The analysis published by D.R. Paul in 1979 [2] showed that, with the exception of natural rubber, at that time PPO was the most permeable polymeric material. Poly (phenylene oxide) retained the reputation of the most permeable glassy polymer for more than a decade. Later on, with appearance on the arena of membrane gas separations of the permeability champion poly [1-(trimethylsylil)-1-propyne], or PTMSP, and of some other interesting glassy polymers like e.g. polyimides [3], the attention of the researchers shifted towards these new materials. Nevertheless, the membrane gas separation-related studies of Polyphenylene ethers continue. The spectrum of materials investigated to date in this respect includes chemically modified poly-2, 6-dimethyl-l,4-phenylene oxide and newly synthesized homologous polyethylene ethers.
V. B. Fenelonov - One of the best experts on this subject based on the ideXlab platform.
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Intrinsic microporosity and gas transport in Polyphenylene oxide polymers
Microporous and Mesoporous Materials, 1999Co-Authors: O M Ilinitch, A A Lapkin, V. B. Fenelonov, L. G. Okkel, V.v. Terskikh, K I ZamaraevAbstract:Abstract Glassy polymers of the Polyphenylene oxide series (PPOs) were investigated using the low-temperature nitrogen adsorption and 129 Xe NMR spectroscopy techniques. The experimental data are indicative of a developed system of interconnected microcavities existing in the polymers. The intrinsic microporosity of PPOs is most probably formed by a continuous three-dimensional network of molecular-sized interstices between the rigid-chain macromolecules. These supposedly constitute the free volume of the polymers. The micropores are likely to be of the ‘throat and cavity’ type, where a cavity may possess several throats. Effective diameters of the throats were estimated to be approximately 0.4 nm at 77 K. It is believed that transport of gas molecules occurs through these micropores. Variations in gas permeability and sorption characteristics, which are dependent on the previous history of the polymer, were investigated and interrelations between these features analyzed. Crystallinity vs. gas permeability relationships for PPO membranes were studied. It is concluded that crystalline and amorphous phases of Polyphenylene Oxides have similar gas permeabilities for the experimental conditions employed. Analysis of the experimental data shows that it is justified to look upon Polyphenylene Oxides as polymeric analogues of solid microporous adsorbents.