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Colin Booth - One of the best experts on this subject based on the ideXlab platform.
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Chain folding in semicrystalline oxybutylene/Oxyethylene/oxybutylene triblock copolymers studied by raman spectroscopy
The Journal of Physical Chemistry B, 2003Co-Authors: Kyriakos Viras, And Antonis Kelarakis, Vasiliki Havredaki, Shao-min Mai And, Anthony J. Ryan, Dharmista Mistry, Withawat Mingvanish, And Paul Mackenzie, Colin BoothAbstract:The chain-folding behavior of short oxybutylene/Oxyethylene/oxybutylene triblock copolymers with one crystallizable E block and two noncrystallizable B blocks has been studied by low-frequency Raman spectroscopy in combination with small-angle X-ray scattering and differential scanning calorimetry. The advantage of using Raman spectroscopy in this application is demonstrated. The results point to folded-chain conformations in which the Oxyethylene blocks are orientated normal to the lamellar end plane. It is probable that the oxybutylene blocks are similarly orientated. Comparison is made with related results for short oxypropylene/Oxyethylene/oxypropylene triblock copolymers.
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Micellization of Diblock and Triblock Copolymers in Aqueous Solution. New Results for Oxyethylene/ Oxybutylene Copolymers E38B12 and E21B11E21. Comparison of Oxyethylene/Oxybutylene, Oxyethylene/Oxypropylene, and Oxyethylene/Alkyl Systems
Langmuir, 1995Co-Authors: Yung-wei Yang, Nanjie Deng, Zu-kang Zhou, David Attwood, Colin BoothAbstract:Two Oxyethylene/oxybutylene block copolymers of similar chain length and composition, E 38 B 12 and E 21 B 11 E 21 , were prepared by sequential anionic polymerization and characterized by gel permeation chromatography and NMR spectroscopy. Their association in dilute aqueous solution was investigated by static and dynamic light scattering. Both copolymers associated by closed processes to form micelles, those of the diblock copolymer being the larger. The increment per B unit in the standard Gibbs energy of micellization of diblock E m B n copolymers was found to be 2.0 kJ mol -1 . The critical micelle concentrations of Oxyethylene/oxybutylene (EmBn and E m B n E m ), Oxyethylene/alkyl (E m C n ), and Oxyethylene/oxypropylene (E m P n E m ) copolymers are compared, and the effect of chain architecture (diblock and triblock) on the association of diblock and triblock copolymers is discussed.
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The Effect of Oxyethylene Sequence Length on the Properties of Poly [ oxymethylene ‐ oligo ( Oxyethylene ) ] / LiClO4 Polymer Electrolytes
Journal of The Electrochemical Society, 1992Co-Authors: H Mehdi Nekoomanesh, Colin Booth, Shin-ichi Nagae, John OwenAbstract:Poly[oxymethylene-oligo(Oxyethylene)]s with uniform Oxyethylene sequence lengths, m=3-6 were prepared by oxymethylene-linking triethylene glycol to hexaethylene glycol. The polymer-LiClO 4 mixtures prepared from polymers with m=4-6 were noncrystalline at room temperature, whereas a polymer-salt complex (T m ∼323 K, 50°C) formed in the mixtures with the polymer with m=3M. T g s increased as salt concentration increased with a linear dependence of 1/T g on c. Maximum conductivities at room temperature were found at salt concentrations in the range 0.7-1.0 mol/kg (O/Li= 20-30)
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preparation and properties of stat copoly Oxyethylene oxypropylene block poly Oxyethylene 1 use of crown ether in the anionic copolymerization of propylene oxide and ethylene oxide
Polymer, 1992Co-Authors: Yulin Deng, Richard H. Mobbs, Frank Heatley, Jifeng Ding, Gaer Yu, Colin Price, Colin BoothAbstract:Abstract Stat-copoly(Oxyethylene-oxypropylene)s were prepared by anionic polymerization initiated by potassium methoxypropanol in the presence of 18-crown-6 ether, and were characterized by g.p.c. and n.m.r. Molecular weight distributions were narrow. Reactivity ratios, determined from composition and from sequence distribution, were rE = 3.1−3.3 and rP = 0.31−0.33, in good agreement with reactivity ratios determined for polymerization without added crown ether. Diblock copolymers with one stat-copoly (Oxyethylene-oxypropylene) block and one poly (Oxyethylene) block were prepared by sequential polymerization, and were characterized by g.p.c. and n.m.r.
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Preparation and properties of stat-copoly-(Oxyethylene-oxypropylene)-block-poly(Oxyethylene): 2. Micellization and gelation properties in aqueous solution
Polymer, 1992Co-Authors: Yulin Deng, Frank Heatley, Jifeng Ding, Colin Price, David Attwood, R.b. Stubbersfield, Colin BoothAbstract:Abstract Aqueous solutions of a range of diblock copolymers with one stat-copoly (Oxyethylene-oxypropylene) block and one poly(Oxyethylene) block were investigated by a variety of techniques, including light scattering, photon correlation spectroscopy, surface tension and electron microscopy. Critical micelle concentrations and temperatures were determined and estimates made of micellar size and shape. The thermodynamic micellization functions were derived, and comparison made with those of a diblock-copoly(Oxyethylene-oxypropylene). Thermally reversible gelation was noted, as were solubilization effects. The composition of the statistical block was of major importance in determining the hydrophobicity of a copolymer, and thereby its micellization and gelation properties.
Shinzo Kohjiya - One of the best experts on this subject based on the ideXlab platform.
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Control on the structure of poly(Oxyethylene) with tri(Oxyethylene) side chains for a polymer solid electrolyte
Solid State Ionics, 2002Co-Authors: Syozo Murakami, Kazuhiro Ueda, Taku Kitade, Yuko Ikeda, Shinzo KohjiyaAbstract:Abstract Structure of poly(Oxyethylene) with tri(Oxyethylene) side chains (TEC) doped with LiClO4 was quantitatively evaluated by using a wide-angle X-ray diffraction (WAXD) method and the relation between the crystallinity of the branched polyether and the ionic conductivity was elucidated. By introducing tri(Oxyethylene) side chains, the crystallinity of TEC became much lower than linear poly(Oxyethylene) (PEO)and the ionic conductivity increased significantly. Further, the change of spherulitic structure was observed by using the polarized light microscope. The structure of the linear poly(Oxyethylene) is the sheaflike spherulites and that of TEC is the spherulites which show the concentric extinction rings due to the influence of side chains. The structure of TEC doped with LiClO4 at the concentration of [Li]/[-O-]=0.05 is the sheaflike spherulites again, but is different from that of poly(Oxyethylene). The sizes of spherulites of TEC doped with LiClO4 are smaller and the bundle of lamellae, which grew to the radial direction, is disordered and thicker than that of poly(Oxyethylene). This is due to the presence of tri(Oxyethylene) side chains and lithium salts between lamellae of poly(Oxyethylene). From the oriented crystallization by uniaxial drawing or shearing, a “stacked lamellae” structure parallel to oriented direction is obtained. The structure may afford different ionic conductivities according to the direction of a material. In other words, anisotropic conductivity may be observed on this oriented material.
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characterization of comb shaped high molecular weight poly Oxyethylene with tri Oxyethylene side chains for a polymer solid electrolyte
Electrochimica Acta, 2000Co-Authors: Yuko Ikeda, Syozo Murakami, Yoshihiko Wada, Yasuo Matoba, Shinzo KohjiyaAbstract:Structure and properties of high molecular weight comb-shaped poly(Oxyethylene)s with tri(Oxyethylene) segments as side chains (TECs) were evaluated as a polymer solid electrolyte. The weight-average molecular weights of the TECs were in the order of 10 6 , and the contents of the side chain were 5, 11 and 18 mol%. The presence of tri(Oxyethylene) side chains decreased the crystallinity of Oxyethylene segments, i.e., TECs with higher side chain content showed lower crystallinity. The crystallite size of Oxyethylene units in TEC films did not change, but the amorphous phase content became higher by the introduction of tri(Oxyethylene) side chains. The crystalline structure in TECs was found to be Form I monoclinic system and a 7:2 helical structure. When LiClO4 was doped in the TECs at the concentration of [Li]:[O]0.05, TECs with 11 and 18 mol% tri(Oxyethylene) segments showed the ionic conductivities in the order of 10 4 Sc m 1 at 30°C and 10 3 Sc m 1 at 80°C, respectively, which were a class of the highest ionic conductivity reported. TECs doped with the salt formed very elastic self-standing film without crosslinking. Salt-doping at the concentration of [Li]:[O] 0.05 decreased the crystallinity of polymers, but the crystallite sizes were almost equal with those of the non-doped films. © 2000 Elsevier Science Ltd. All rights reserved.
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comb shaped high molecular weight polyether consisting of Oxyethylene units for polymer solid electrolyte
Polymer International, 1997Co-Authors: Yuko Ikeda, Yasuo Matoba, H Masui, S Syoji, T Sakashita, Shinzo KohjiyaAbstract:Novel high molecular weight comb-shaped polyethers were synthesized and used as the matrix of a polymer solid electrolyte. Both the main chain and the side chain of these polyethers consist of Oxyethylene units. The new polyethers possess film-forming properties, because the weight-average molecular weights were over 106. The short side chains of Oxyethylene units gave rise to less crystallization of poly(Oxyethylene) segments and to an increase of ionic conductivity when doped with lithium perchlorate. © 1997 SCI.
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Comb‐shaped High Molecular Weight Polyether Consisting of Oxyethylene Units for Polymer Solid Electrolyte
Polymer International, 1997Co-Authors: Yuko Ikeda, Yasuo Matoba, H Masui, S Syoji, T Sakashita, Shinzo KohjiyaAbstract:Novel high molecular weight comb-shaped polyethers were synthesized and used as the matrix of a polymer solid electrolyte. Both the main chain and the side chain of these polyethers consist of Oxyethylene units. The new polyethers possess film-forming properties, because the weight-average molecular weights were over 106. The short side chains of Oxyethylene units gave rise to less crystallization of poly(Oxyethylene) segments and to an increase of ionic conductivity when doped with lithium perchlorate. © 1997 SCI.
Yuko Ikeda - One of the best experts on this subject based on the ideXlab platform.
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Control on the structure of poly(Oxyethylene) with tri(Oxyethylene) side chains for a polymer solid electrolyte
Solid State Ionics, 2002Co-Authors: Syozo Murakami, Kazuhiro Ueda, Taku Kitade, Yuko Ikeda, Shinzo KohjiyaAbstract:Abstract Structure of poly(Oxyethylene) with tri(Oxyethylene) side chains (TEC) doped with LiClO4 was quantitatively evaluated by using a wide-angle X-ray diffraction (WAXD) method and the relation between the crystallinity of the branched polyether and the ionic conductivity was elucidated. By introducing tri(Oxyethylene) side chains, the crystallinity of TEC became much lower than linear poly(Oxyethylene) (PEO)and the ionic conductivity increased significantly. Further, the change of spherulitic structure was observed by using the polarized light microscope. The structure of the linear poly(Oxyethylene) is the sheaflike spherulites and that of TEC is the spherulites which show the concentric extinction rings due to the influence of side chains. The structure of TEC doped with LiClO4 at the concentration of [Li]/[-O-]=0.05 is the sheaflike spherulites again, but is different from that of poly(Oxyethylene). The sizes of spherulites of TEC doped with LiClO4 are smaller and the bundle of lamellae, which grew to the radial direction, is disordered and thicker than that of poly(Oxyethylene). This is due to the presence of tri(Oxyethylene) side chains and lithium salts between lamellae of poly(Oxyethylene). From the oriented crystallization by uniaxial drawing or shearing, a “stacked lamellae” structure parallel to oriented direction is obtained. The structure may afford different ionic conductivities according to the direction of a material. In other words, anisotropic conductivity may be observed on this oriented material.
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Elastomeric poly(Oxyethylene) matrixes for ion conduction
Journal of Applied Polymer Science, 2000Co-Authors: Yuko IkedaAbstract:Molecular design of elastomeric polymer solid electrolytes was presented, whose concept was based on the rubbery state of polymer. For the ionic conduction, elastomeric amorphous poly(Oxyethylene) (POE) matrixes were produced by the copolymerization technique. At first, high molecular mass copolymers were synthesized by copolymerization of ethylene oxide (EO) with epichlorohydrin (EH), and the ionic conductivity was evaluated for the samples doped with lithium perchlorate. The EH units, however, did not contribute to the ion conduction, although the EH units were effective for preventing the crystallization of POE segments. Next, high molecular mass comb-shaped POEs with Oxyethylene segments as side chains were synthesized. Both main chain and side chains were Oxyethylene units, and the molecular mass was on the order of 106. The Oxyethylene side chains were found to be useful for solvating the salt and the preventing the crystallization of POE segments. Consequently, the high molecular mass comb-shaped POEs with Oxyethylene side chains showed the higher ionic conductivity when doped with lithium perchlorate or lithium bis(trifluoromethanesulfonyl)imide. The structure and mechanical properties of comb-shaped POEs were also reported, and the usefulness of the concept for the molecular design of elastomeric polymer solid electrolytes was displayed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1530–1540, 2000
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characterization of comb shaped high molecular weight poly Oxyethylene with tri Oxyethylene side chains for a polymer solid electrolyte
Electrochimica Acta, 2000Co-Authors: Yuko Ikeda, Syozo Murakami, Yoshihiko Wada, Yasuo Matoba, Shinzo KohjiyaAbstract:Structure and properties of high molecular weight comb-shaped poly(Oxyethylene)s with tri(Oxyethylene) segments as side chains (TECs) were evaluated as a polymer solid electrolyte. The weight-average molecular weights of the TECs were in the order of 10 6 , and the contents of the side chain were 5, 11 and 18 mol%. The presence of tri(Oxyethylene) side chains decreased the crystallinity of Oxyethylene segments, i.e., TECs with higher side chain content showed lower crystallinity. The crystallite size of Oxyethylene units in TEC films did not change, but the amorphous phase content became higher by the introduction of tri(Oxyethylene) side chains. The crystalline structure in TECs was found to be Form I monoclinic system and a 7:2 helical structure. When LiClO4 was doped in the TECs at the concentration of [Li]:[O]0.05, TECs with 11 and 18 mol% tri(Oxyethylene) segments showed the ionic conductivities in the order of 10 4 Sc m 1 at 30°C and 10 3 Sc m 1 at 80°C, respectively, which were a class of the highest ionic conductivity reported. TECs doped with the salt formed very elastic self-standing film without crosslinking. Salt-doping at the concentration of [Li]:[O] 0.05 decreased the crystallinity of polymers, but the crystallite sizes were almost equal with those of the non-doped films. © 2000 Elsevier Science Ltd. All rights reserved.
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comb shaped high molecular weight polyether consisting of Oxyethylene units for polymer solid electrolyte
Polymer International, 1997Co-Authors: Yuko Ikeda, Yasuo Matoba, H Masui, S Syoji, T Sakashita, Shinzo KohjiyaAbstract:Novel high molecular weight comb-shaped polyethers were synthesized and used as the matrix of a polymer solid electrolyte. Both the main chain and the side chain of these polyethers consist of Oxyethylene units. The new polyethers possess film-forming properties, because the weight-average molecular weights were over 106. The short side chains of Oxyethylene units gave rise to less crystallization of poly(Oxyethylene) segments and to an increase of ionic conductivity when doped with lithium perchlorate. © 1997 SCI.
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Comb‐shaped High Molecular Weight Polyether Consisting of Oxyethylene Units for Polymer Solid Electrolyte
Polymer International, 1997Co-Authors: Yuko Ikeda, Yasuo Matoba, H Masui, S Syoji, T Sakashita, Shinzo KohjiyaAbstract:Novel high molecular weight comb-shaped polyethers were synthesized and used as the matrix of a polymer solid electrolyte. Both the main chain and the side chain of these polyethers consist of Oxyethylene units. The new polyethers possess film-forming properties, because the weight-average molecular weights were over 106. The short side chains of Oxyethylene units gave rise to less crystallization of poly(Oxyethylene) segments and to an increase of ionic conductivity when doped with lithium perchlorate. © 1997 SCI.
Yulin Deng - One of the best experts on this subject based on the ideXlab platform.
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preparation and properties of stat copoly Oxyethylene oxypropylene block poly Oxyethylene 1 use of crown ether in the anionic copolymerization of propylene oxide and ethylene oxide
Polymer, 1992Co-Authors: Yulin Deng, Richard H. Mobbs, Frank Heatley, Jifeng Ding, Gaer Yu, Colin Price, Colin BoothAbstract:Abstract Stat-copoly(Oxyethylene-oxypropylene)s were prepared by anionic polymerization initiated by potassium methoxypropanol in the presence of 18-crown-6 ether, and were characterized by g.p.c. and n.m.r. Molecular weight distributions were narrow. Reactivity ratios, determined from composition and from sequence distribution, were rE = 3.1−3.3 and rP = 0.31−0.33, in good agreement with reactivity ratios determined for polymerization without added crown ether. Diblock copolymers with one stat-copoly (Oxyethylene-oxypropylene) block and one poly (Oxyethylene) block were prepared by sequential polymerization, and were characterized by g.p.c. and n.m.r.
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Preparation and properties of stat-copoly-(Oxyethylene-oxypropylene)-block-poly(Oxyethylene): 2. Micellization and gelation properties in aqueous solution
Polymer, 1992Co-Authors: Yulin Deng, Frank Heatley, Jifeng Ding, Colin Price, David Attwood, R.b. Stubbersfield, Colin BoothAbstract:Abstract Aqueous solutions of a range of diblock copolymers with one stat-copoly (Oxyethylene-oxypropylene) block and one poly(Oxyethylene) block were investigated by a variety of techniques, including light scattering, photon correlation spectroscopy, surface tension and electron microscopy. Critical micelle concentrations and temperatures were determined and estimates made of micellar size and shape. The thermodynamic micellization functions were derived, and comparison made with those of a diblock-copoly(Oxyethylene-oxypropylene). Thermally reversible gelation was noted, as were solubilization effects. The composition of the statistical block was of major importance in determining the hydrophobicity of a copolymer, and thereby its micellization and gelation properties.
Jong-chan Lee - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and Characterization of Biocidal Poly(Oxyethylene)s Having N-Halamine Side Groups
Macromolecular Research, 2011Co-Authors: Kwonyong Choi, Moon-ja Nam, Jee Yeon Kim, Jeyong Yoon, Jong-chan LeeAbstract:Biocidal poly(Oxyethylene)s with N-halamine side groups were prepared using polymer analogous reactions of poly[oxy(chloromethyl)ethylene] with 5,5-dimethylhydantoin followed by chlorination. The biocidal poly(Oxyethylene) films effectively inactivated the gram-negative bacteria Escherichia coli and maintained their biocidal property after long-term (3-month) storage. Since biocidal poly(Oxyethylene) films have antibacterial efficacy and stability on hard surfaces, they could be useful in a variety of household and medical antibacterial applications. Open image in new window
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inhibition of bacterial adhesion on well ordered comb like polymer surfaces
Colloids and Surfaces B: Biointerfaces, 2010Co-Authors: Eunho Sohn, Jeyong Yoon, Jaeeun Kim, Byoung Gak Kim, Junil Kang, Jaeseung Chung, Jooyeon Ahn, Jong-chan LeeAbstract:The surfaces of comb-like poly(Oxyethylene) derivatives with n-alkylsulfonyl side groups were more effective at reducing Pseudomonas aeruginosa adhesion than the surfaces of common materials such as polystyrene, poly(methyl methacrylate), poly(dimethylsiloxane), fluorinated polyacrylate, and glass. When the comb-like poly(Oxyethylene) was mixed with polystyrene and poly(methyl methacrylate), the topology and roughness of the surfaces varied according to the mixture compositions. However the surface energies of the mixtures were close to that of the comb-like poly(Oxyethylene) in the range of 21-23 mN/m and bacterial adhesion resistances of the mixture surfaces were also comparable to that of the pure comb-like poly(Oxyethylene) surface.
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Amphiphilic Comb‐Like Poly(Oxyethylene) and Its Complexes with LiClO4: Synthesis and Mesomorphic Behavior
Macromolecular Rapid Communications, 2004Co-Authors: Jong-uk Kim, Sang-ho Cha, Jong-chan LeeAbstract:We prepared an amphiphilic, comb-like poly-(Oxyethylene)containing decyl-tri(Oxyethylene)amphiphiles in the side chain using polymer analogous reaction to obtain a novel nonionic amphilphilic polymeric system with high molecular weight. The amphiphilic comb-like poly(Oxyethylene) itself only showed a side-chair crystalline phase below its melting temperature of -31°C. When the polymer was mixed with lithium perchlorate, a smectic liquid-crystalline phase appeared. The ordered phases of the polymer and the polymer mixture were studied by differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction.
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Synthesis and Properties of Liquid Crystalline Polymers Containing an Oxyethylene Backbone and n-Octylsulfonylmethyl Side Groups
Macromolecules, 1998Co-Authors: Jong-chan Lee, Morton H. Litt, Charles E. RogersAbstract:Poly(Oxyethylene)s containing n-octylthiomethyl side groups were synthesized by the reaction of poly[oxy(chloromethyl)ethylene] (CE) and sodium n-octanethiolate in DMAc. These were oxidized to poly(Oxyethylene)s containing n-octylsulfonylmethyl side groups. When the mole percentage of sulfur containing monomeric units in the copolymers was about 60% or more, ordered phases formed. Structural analysis of the ordered phase of poly(Oxyethylene)s containing n-octylthiomethyl side groups is in progress. The ordered phase of poly(Oxyethylene)s containing n-octylsulfonylmethyl side groups was studied using differential scanning calorimetry, cross-polarizing optical microscopy, and X-ray diffraction. It was found to be a smectic A liquid crystalline phase.
