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Tomokazu Yoshimura - One of the best experts on this subject based on the ideXlab platform.
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adsorption and aggregation properties of alkoxy group modified homogeneous polyoxyethylene Alkyl Ether nonionic surfactants
Journal of Molecular Liquids, 2019Co-Authors: Shiho Yada, Satoru Hashimoto, Toshiyuki Suzuki, Tomokazu YoshimuraAbstract:Abstract The development of new surfactants with interesting properties and new functionalities that can be controlled in a simple manner is an important industrial objective. Herein, we report the synthesis of homogeneous polyoxyethylene (EO) Alkyl Ether nonionic surfactants modified with alkoxy groups (C12EO8OR, where C12 and EO8 are dodecyl and octaoxyethylene chains, respectively, and R = Me and Et) from a homogeneous EO-type hexaoxyethylene dodecyl Ether (C12EO6) and diethylene glycol monomethyl Ether or diethylene glycol monoethyl Ether. The adsorption and aggregation properties of these surfactants were characterized through cloud point and surface tension measurements, and by small-angle X-ray scattering, polarization microscopy, and cryogenic transmission electron microscopy; these properties were compared to those of previously reported homogeneous EO-type (C12EO8) and polyoxypropylene-polyoxyethylene type surfactants (C12EO8POy, y = 1, 2, 3). The introduction of a methoxy or ethoxy group at the terminus of the EO chain in C12EO8 resulted in an increase in hydrophobicity and a greatly reduced cloud point. Substitution of the terminal hydroxy group of the EO chain in C12EO8 with methoxy and then ethoxy led to increasingly lower surface tensions in solution and more efficient air/water interfacial adsorption. C12EO8OR formed small micelles at low concentrations in solution, and the micelles of C12EO8OMe transformed to hexagonal liquid crystals with increasing surfactant concentration, whereas C12EO8OEt remained to form micelles even at high concentration; that is, the introduction of bulkier functional groups into the C12EO8 surfactant helps to control the formation of aggregates with higher-order structures.
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structure and catalytic activities of gold nanoparticles protected by homogeneous polyoxyethylene Alkyl Ether type nonionic surfactants
Langmuir, 2019Co-Authors: Shiho Yada, Tomokazu YoshimuraAbstract:Gold nanoparticles were prepared in aqueous solutions containing four homogeneous polyoxyethylene (EO) Alkyl Ether type nonionic surfactants: octaoxyethylene dodecyl Ether (C12EO8), methoxyoctaoxyethylene dodecyl Ether (C12EO8OMe), ethoxyoctaoxyethylene dodecyl Ether (C12EO8OEt), and trioxypropylene-octaoxyethylene dodecyl Ether (C12EO8PO3). The sizes of obtained gold nanoparticles were almost independent of the terminal group in the EO surfactants; and the average sizes of nanoparticles prepared by surfactants with hydroxy, methoxy, ethoxy, and trioxypropylene terminal groups at [surfactant]:[Au3+] = 1:1 were 5.1 ± 1.2, 8.1 ± 1.4, 6.4 ± 2.1, and 8.6 ± 2.9 nm, respectively. The gold nanoparticles easily aggregated togEther according to the increasing hydrophobicity of hydroxy < methoxy ethoxy < trioxypropylene terminal groups. Highly stable dispersed nanoparticles were observed with hydroxy group in the EO terminal group. On the other hand, introducing hydrophobic moiety to the hydroxy group resulted in a...
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emulsification solubilization and detergency behaviors of homogeneous polyoxypropylene polyoxyethylene Alkyl Ether type nonionic surfactants
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019Co-Authors: Shiho Yada, Yu Nagai Kanasaki, Keisuke Matsuoka, Keiko Gotoh, Tomokazu YoshimuraAbstract:Abstract The emulsification and solubilization properties and detergency behaviors were investigated using homogeneous polyoxypropylene-polyoxyethylene (PO-EO) Alkyl Ether type nonionic surfactants (C12EOxPO3, where x represents EO chain lengths of 6 and 8, and C12 and PO3 indicate the dodecyl chain and single trioxypropylene chain, respectively) and polyoxyethylene (EO) Alkyl Ether type nonionic surfactants (C12EOx, x = 6 and 8). These nonionic surfactants possess single EO and PO chain lengths without a distribution. An oil-in-water (O/W) type emulsion prepared using mixtures of nonionic surfactant C12EOxPO3 or C12EOx solutions and squalane was shown to be stable in the order of C12EO6PO3
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adsorption dynamics of homogeneous polyoxypropylene polyoxyethylene Alkyl Ether nonionic surfactants at the air water interface
Journal of Molecular Liquids, 2018Co-Authors: Shiho Yada, Satoru Hashimoto, Toshiyuki Suzuki, Tomokazu YoshimuraAbstract:Abstract The dynamic surface tensions of two homogeneous polyoxyethylene (EO) Alkyl Ether nonionic surfactants with terminal hydroxy group (C12EOx, where C12 is a dodecyl chain and x is the length of the EO chain; x = 6, 8) and two homogeneous polyoxypropylene-polyoxyethylene (PO-EO) Alkyl Ether nonionic surfactants (C12EOxPO3, where PO3 is a trioxypropylene chain inserted between the EOx and the terminal hydroxy group) were measured using the maximum bubble pressure method. The effects of EO chain length, the presence or absence of the PO3 chain, and the surfactant concentration on the maximum rates of surface-tension reduction and diffusion coefficient were investigated. The C12EO6PO3 surfactant exhibited the fastest rate of surface-tension reduction of the four systems studied, despite its complex hydrophobic-Alkyl-chain/hydrophilic-EO-chain/hydrophobic-PO-chain structure that differs from that of conventional EO Alkyl Ether surfactants. The diffusion coefficients obtained from short and long time analyses indicate that surfactant diffusion to the subsurface is faster for the C12EOxPO3 surfactants than the C12EOx surfactants (short time data), while surfactant adsorption from the subsurface to the air/water interface is faster for the C12EOx surfactants than the C12EOxPO3 surfactants (long time data).
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Adsorption dynamics of homogeneous polyoxypropylene-polyoxyethylene Alkyl Ether nonionic surfactants at the air/water interface
Journal of Molecular Liquids, 2018Co-Authors: Shiho Yada, Satoru Hashimoto, Toshiyuki Suzuki, Tomokazu YoshimuraAbstract:Abstract The dynamic surface tensions of two homogeneous polyoxyethylene (EO) Alkyl Ether nonionic surfactants with terminal hydroxy group (C12EOx, where C12 is a dodecyl chain and x is the length of the EO chain; x = 6, 8) and two homogeneous polyoxypropylene-polyoxyethylene (PO-EO) Alkyl Ether nonionic surfactants (C12EOxPO3, where PO3 is a trioxypropylene chain inserted between the EOx and the terminal hydroxy group) were measured using the maximum bubble pressure method. The effects of EO chain length, the presence or absence of the PO3 chain, and the surfactant concentration on the maximum rates of surface-tension reduction and diffusion coefficient were investigated. The C12EO6PO3 surfactant exhibited the fastest rate of surface-tension reduction of the four systems studied, despite its complex hydrophobic-Alkyl-chain/hydrophilic-EO-chain/hydrophobic-PO-chain structure that differs from that of conventional EO Alkyl Ether surfactants. The diffusion coefficients obtained from short and long time analyses indicate that surfactant diffusion to the subsurface is faster for the C12EOxPO3 surfactants than the C12EOx surfactants (short time data), while surfactant adsorption from the subsurface to the air/water interface is faster for the C12EOx surfactants than the C12EOxPO3 surfactants (long time data).
Shiho Yada - One of the best experts on this subject based on the ideXlab platform.
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adsorption and aggregation properties of alkoxy group modified homogeneous polyoxyethylene Alkyl Ether nonionic surfactants
Journal of Molecular Liquids, 2019Co-Authors: Shiho Yada, Satoru Hashimoto, Toshiyuki Suzuki, Tomokazu YoshimuraAbstract:Abstract The development of new surfactants with interesting properties and new functionalities that can be controlled in a simple manner is an important industrial objective. Herein, we report the synthesis of homogeneous polyoxyethylene (EO) Alkyl Ether nonionic surfactants modified with alkoxy groups (C12EO8OR, where C12 and EO8 are dodecyl and octaoxyethylene chains, respectively, and R = Me and Et) from a homogeneous EO-type hexaoxyethylene dodecyl Ether (C12EO6) and diethylene glycol monomethyl Ether or diethylene glycol monoethyl Ether. The adsorption and aggregation properties of these surfactants were characterized through cloud point and surface tension measurements, and by small-angle X-ray scattering, polarization microscopy, and cryogenic transmission electron microscopy; these properties were compared to those of previously reported homogeneous EO-type (C12EO8) and polyoxypropylene-polyoxyethylene type surfactants (C12EO8POy, y = 1, 2, 3). The introduction of a methoxy or ethoxy group at the terminus of the EO chain in C12EO8 resulted in an increase in hydrophobicity and a greatly reduced cloud point. Substitution of the terminal hydroxy group of the EO chain in C12EO8 with methoxy and then ethoxy led to increasingly lower surface tensions in solution and more efficient air/water interfacial adsorption. C12EO8OR formed small micelles at low concentrations in solution, and the micelles of C12EO8OMe transformed to hexagonal liquid crystals with increasing surfactant concentration, whereas C12EO8OEt remained to form micelles even at high concentration; that is, the introduction of bulkier functional groups into the C12EO8 surfactant helps to control the formation of aggregates with higher-order structures.
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structure and catalytic activities of gold nanoparticles protected by homogeneous polyoxyethylene Alkyl Ether type nonionic surfactants
Langmuir, 2019Co-Authors: Shiho Yada, Tomokazu YoshimuraAbstract:Gold nanoparticles were prepared in aqueous solutions containing four homogeneous polyoxyethylene (EO) Alkyl Ether type nonionic surfactants: octaoxyethylene dodecyl Ether (C12EO8), methoxyoctaoxyethylene dodecyl Ether (C12EO8OMe), ethoxyoctaoxyethylene dodecyl Ether (C12EO8OEt), and trioxypropylene-octaoxyethylene dodecyl Ether (C12EO8PO3). The sizes of obtained gold nanoparticles were almost independent of the terminal group in the EO surfactants; and the average sizes of nanoparticles prepared by surfactants with hydroxy, methoxy, ethoxy, and trioxypropylene terminal groups at [surfactant]:[Au3+] = 1:1 were 5.1 ± 1.2, 8.1 ± 1.4, 6.4 ± 2.1, and 8.6 ± 2.9 nm, respectively. The gold nanoparticles easily aggregated togEther according to the increasing hydrophobicity of hydroxy < methoxy ethoxy < trioxypropylene terminal groups. Highly stable dispersed nanoparticles were observed with hydroxy group in the EO terminal group. On the other hand, introducing hydrophobic moiety to the hydroxy group resulted in a...
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emulsification solubilization and detergency behaviors of homogeneous polyoxypropylene polyoxyethylene Alkyl Ether type nonionic surfactants
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019Co-Authors: Shiho Yada, Yu Nagai Kanasaki, Keisuke Matsuoka, Keiko Gotoh, Tomokazu YoshimuraAbstract:Abstract The emulsification and solubilization properties and detergency behaviors were investigated using homogeneous polyoxypropylene-polyoxyethylene (PO-EO) Alkyl Ether type nonionic surfactants (C12EOxPO3, where x represents EO chain lengths of 6 and 8, and C12 and PO3 indicate the dodecyl chain and single trioxypropylene chain, respectively) and polyoxyethylene (EO) Alkyl Ether type nonionic surfactants (C12EOx, x = 6 and 8). These nonionic surfactants possess single EO and PO chain lengths without a distribution. An oil-in-water (O/W) type emulsion prepared using mixtures of nonionic surfactant C12EOxPO3 or C12EOx solutions and squalane was shown to be stable in the order of C12EO6PO3
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adsorption dynamics of homogeneous polyoxypropylene polyoxyethylene Alkyl Ether nonionic surfactants at the air water interface
Journal of Molecular Liquids, 2018Co-Authors: Shiho Yada, Satoru Hashimoto, Toshiyuki Suzuki, Tomokazu YoshimuraAbstract:Abstract The dynamic surface tensions of two homogeneous polyoxyethylene (EO) Alkyl Ether nonionic surfactants with terminal hydroxy group (C12EOx, where C12 is a dodecyl chain and x is the length of the EO chain; x = 6, 8) and two homogeneous polyoxypropylene-polyoxyethylene (PO-EO) Alkyl Ether nonionic surfactants (C12EOxPO3, where PO3 is a trioxypropylene chain inserted between the EOx and the terminal hydroxy group) were measured using the maximum bubble pressure method. The effects of EO chain length, the presence or absence of the PO3 chain, and the surfactant concentration on the maximum rates of surface-tension reduction and diffusion coefficient were investigated. The C12EO6PO3 surfactant exhibited the fastest rate of surface-tension reduction of the four systems studied, despite its complex hydrophobic-Alkyl-chain/hydrophilic-EO-chain/hydrophobic-PO-chain structure that differs from that of conventional EO Alkyl Ether surfactants. The diffusion coefficients obtained from short and long time analyses indicate that surfactant diffusion to the subsurface is faster for the C12EOxPO3 surfactants than the C12EOx surfactants (short time data), while surfactant adsorption from the subsurface to the air/water interface is faster for the C12EOx surfactants than the C12EOxPO3 surfactants (long time data).
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Adsorption dynamics of homogeneous polyoxypropylene-polyoxyethylene Alkyl Ether nonionic surfactants at the air/water interface
Journal of Molecular Liquids, 2018Co-Authors: Shiho Yada, Satoru Hashimoto, Toshiyuki Suzuki, Tomokazu YoshimuraAbstract:Abstract The dynamic surface tensions of two homogeneous polyoxyethylene (EO) Alkyl Ether nonionic surfactants with terminal hydroxy group (C12EOx, where C12 is a dodecyl chain and x is the length of the EO chain; x = 6, 8) and two homogeneous polyoxypropylene-polyoxyethylene (PO-EO) Alkyl Ether nonionic surfactants (C12EOxPO3, where PO3 is a trioxypropylene chain inserted between the EOx and the terminal hydroxy group) were measured using the maximum bubble pressure method. The effects of EO chain length, the presence or absence of the PO3 chain, and the surfactant concentration on the maximum rates of surface-tension reduction and diffusion coefficient were investigated. The C12EO6PO3 surfactant exhibited the fastest rate of surface-tension reduction of the four systems studied, despite its complex hydrophobic-Alkyl-chain/hydrophilic-EO-chain/hydrophobic-PO-chain structure that differs from that of conventional EO Alkyl Ether surfactants. The diffusion coefficients obtained from short and long time analyses indicate that surfactant diffusion to the subsurface is faster for the C12EOxPO3 surfactants than the C12EOx surfactants (short time data), while surfactant adsorption from the subsurface to the air/water interface is faster for the C12EOx surfactants than the C12EOxPO3 surfactants (long time data).
Hubert Kuhn - One of the best experts on this subject based on the ideXlab platform.
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molecular fragment dynamics study on the water air interface behavior of non ionic polyoxyethylene Alkyl Ether surfactants
Journal of Cheminformatics, 2014Co-Authors: Andreas Truszkowski, Annamaria Fiethen, Thomas Wiebringhaus, Hubert Kuhn, Achim Zielesny, Matthias EppleAbstract:Molecular Fragment Dynamics (MFD) is a mesoscopic simulation technique based on Dissipative Particle Dynamics (DPD). Whereas DPD beads in general may not necessarily be identified with chemical compounds at all the MFD variant uses specific molecules or molecular fragments as its basic coarse-grained interacting entities (rather than the fine-grained atom types of Molecular Mechanics). MFD can be used to study formulations of drugs and active agents in oil, water and emulsions. MFD simulations of the nonionic polyoxyethylene Alkyl Ether surfactants C6E6, C10E6, C12E6 and C16E6 at the water-air interface are performed to study their nanoscale structures and surface properties. The simulations of the self-aggregation of the polyoxyethylene Alkyl Ether surfactants lead to equilibrium nanoscale structures and computationally determined surface tensions which are in agreement with experimental data for different surfactant concentrations [1]. Figure 1
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molecular fragment dynamics study on the water air interface behavior of non ionic polyoxyethylene Alkyl Ether surfactants
Journal of Colloid and Interface Science, 2013Co-Authors: Andreas Truszkowski, Annamaria Fiethen, Achim Zielesny, Matthias Epple, Hubert KuhnAbstract:Abstract Molecular fragment dynamics (MFD) is a mesoscopic simulation technique based on dissipative particle dynamics (DPD). MFD simulations of the self-aggregation of the polyoxyethylene Alkyl Ether surfactants C6E6, C10E6, C12E6 and C16E6 at the water–air surface lead to equilibrium nanoscale structures and computationally determined surface tensions which are in agreement with experimental data for different surfactant concentrations. Thus, molecular fragment dynamics is a well-suited predictive technique to study the behavior of new surfactant systems.
Matthias Epple - One of the best experts on this subject based on the ideXlab platform.
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molecular fragment dynamics study on the water air interface behavior of non ionic polyoxyethylene Alkyl Ether surfactants
Journal of Cheminformatics, 2014Co-Authors: Andreas Truszkowski, Annamaria Fiethen, Thomas Wiebringhaus, Hubert Kuhn, Achim Zielesny, Matthias EppleAbstract:Molecular Fragment Dynamics (MFD) is a mesoscopic simulation technique based on Dissipative Particle Dynamics (DPD). Whereas DPD beads in general may not necessarily be identified with chemical compounds at all the MFD variant uses specific molecules or molecular fragments as its basic coarse-grained interacting entities (rather than the fine-grained atom types of Molecular Mechanics). MFD can be used to study formulations of drugs and active agents in oil, water and emulsions. MFD simulations of the nonionic polyoxyethylene Alkyl Ether surfactants C6E6, C10E6, C12E6 and C16E6 at the water-air interface are performed to study their nanoscale structures and surface properties. The simulations of the self-aggregation of the polyoxyethylene Alkyl Ether surfactants lead to equilibrium nanoscale structures and computationally determined surface tensions which are in agreement with experimental data for different surfactant concentrations [1]. Figure 1
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molecular fragment dynamics study on the water air interface behavior of non ionic polyoxyethylene Alkyl Ether surfactants
Journal of Colloid and Interface Science, 2013Co-Authors: Andreas Truszkowski, Annamaria Fiethen, Achim Zielesny, Matthias Epple, Hubert KuhnAbstract:Abstract Molecular fragment dynamics (MFD) is a mesoscopic simulation technique based on dissipative particle dynamics (DPD). MFD simulations of the self-aggregation of the polyoxyethylene Alkyl Ether surfactants C6E6, C10E6, C12E6 and C16E6 at the water–air surface lead to equilibrium nanoscale structures and computationally determined surface tensions which are in agreement with experimental data for different surfactant concentrations. Thus, molecular fragment dynamics is a well-suited predictive technique to study the behavior of new surfactant systems.
Kuniaki Tatsumi - One of the best experts on this subject based on the ideXlab platform.
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low melting low viscous hydrophobic ionic liquids n Alkyl Alkyl Ether n methylpyrrolidinium perfluoroethyltrifluoroborate
ChemInform, 2005Co-Authors: Zhibin Zhou, Hajime Matsumoto, Kuniaki TatsumiAbstract:A series of new hydrophobic ionic liquids comprising N-Alkyl(Alkyl Ether)-N-methylpyrrolidinium and perfluoroethyltrifluoroborate were prepared and characterized. The new [C2F5BF3]−-based salts sho...
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low melting low viscous hydrophobic ionic liquids 1 Alkyl Alkyl Ether 3 methylimidazolium perfluoroAlkyltrifluoroborate
Chemistry: A European Journal, 2004Co-Authors: Zhibin Zhou, Hajime Matsumoto, Kuniaki TatsumiAbstract:A series of twenty two hydrophobic ionic liquids, 1-Alkyl(Alkyl Ether)-3-methylimidazolium ([C(m)mim]+ or [C(m)O(n)mim]+; where Cm is 1-Alkyl, Cm = nCmH(2m+1), m = 1-4 and 6; C(m)O(n) is 1-Alkyl Ether, C2O1 = CH3OCH2, C3O1 = CH3OCH2CH2, and C5O2 = CH3(OCH2CH2)2) perfluoroAlkyltrifluoroborate ([RFBF3]-, RF = CF3, C2F5, nC3F7, nC4F9), have been prepared and characterized. Some of the important physicochemical properties of these salts including melting point, glass transition, viscosity, density, ionic conductivity, thermal and electrochemical stability, have been determined and were compared with those of the reported [BF4](-)-based ones. The influence of the structure variation in the imidazolium cation and the perfluoroAlkyltrifluoroborate ([RFBF3]-) anion on the above physicochemical properties was discussed. The key features of these new salts are their low melting points (-42 to 35 degrees C) or extremely low glass transition (between -87 and -117 degrees C) without melting, and considerably low viscosities (26-77 cP at 25 degrees C).
