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Makoto Aratono - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Surface Freezing on Stability of Oil-in-Water Emulsions
    2018
    Co-Authors: Yuhei Tokiwa, Takanori Takiue, Makoto Aratono, Hiroki Matsubara, Hiromu Sakamoto, Colin D. Bain
    Abstract:

    Penetration of alkane molecules into the Adsorbed Film of a cationic surfactant gives rise to a surface freezing transition at the alkane–water interface upon cooling. In this paper, we show that surface freezing of hexadecyl­trimethyl­ammonium chloride (CTAC) at the tetradecane–water interface stabilizes oil-in-water (OW) emulsions. For concentrations of CTAC near the critical micelle concentration, an OW emulsion coalesced readily above the surface freezing transition whereas the OW emulsion was stable in the surface frozen state. There was a discontinuous change in the stability of the OW emulsion at a temperature very close to the surface phase transition temperature as determined by interfacial tensiometry and ellipsometry on a planar oil–water interface. The mechanical elasticity of the surface frozen layer opposes Film drainage and density fluctuations that could lead to rupture and is the most likely cause of the enhanced emulsion stability

  • Adsorbed Film of n tetradecylphosphocholine at the tetradecane water interface studied by interfacial tensiometry and x ray reflection
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015
    Co-Authors: Shinya Hiraki, Makoto Aratono, Hiroki Matsubara, Toshiaki Ina, Kiyofumi Nitta, Hajime Tanida, Tomoya Uruga, T Goto, Takanori Takiue
    Abstract:

    Abstract The Adsorbed Film of n-tetradecylphosphocholine (C14PC) at the tetradecane (C14)/aqueous solution (W) interface was studied by interfacial tensiometry and X-ray reflection (XR). The interfacial tension γ was measured as a function of molality m C 14 PC and temperature T under atmospheric pressure. The interfacial density of C14PC Γ C 14 PC H increases with increasing m C 14 PC and converges into 3 μmol m−2 (first saturation) at m C 14 PC ≈ 0.08 mmol kg − 1 and into 4.2 μmol m−2 (second saturation) at the critical micelle concentration (CMC). The electron density profile determined by XR indicated that C14PC molecules form monolayer with relatively loose packing at the first saturation. In the second saturation, on the other hand, the molecules form bilayer in which charge separated phosphocholine groups take upside-down arrangement to interact attractively between neighbors. The positive entropy changes associated with adsorption both from monomeric and from micellar states result from that the contribution of dehydration around C14PC molecules, especially around PC groups, by the adsorption from aqueous solution overcomes that of a comparatively ordered molecular orientation at the interface. By comparing the results at the C14/W interface with those at the Air (A)/W one, it was shown that in the monolayer and bilayer states, hydrophobic chains of C14PC molecules are more ordered at the C14/W than at the A/W interface because of attractive interaction between C14PC and C14 molecules. This leads to smaller value of the partial molar entropy and energy changes associated with the adsorption at the C14/W than at the A/W interface. Furthermore the entropy of micelle formation changes from positive to negative with increasing T, suggesting that the entropy gain due to the dehydration exceeds the entropy loss by the aggregation at low temperatures, while the gain is less than the loss at high temperature.

  • effect of alkane chain length and counterion on the freezing transition of cationic surfactant Adsorbed Film at alkane mixture water interfaces
    Journal of Physical Chemistry B, 2015
    Co-Authors: Yuhei Tokiwa, Takanori Takiue, Makoto Aratono, Hiroyasu Sakamoto, Hiroki Matsubara
    Abstract:

    Penetration of alkane molecules into the Adsorbed Film gives rise to a surface freezing transition of cationic surfactant at the alkane–water interface. To examine the effect of the alkane chain length and counterion on the surface freezing, we employed interfacial tensiometry and ellipsometry to study the interface of cetyltrimethylammonium bromide and cetyltrimethylammonium chloride aqueous solutions against dodecane, tetradecane, hexadecane, and their mixtures. Applying theoretical equations to the experimental results obtained, we found that the alkane molecules that have the same chain length as the surfactant adsorb preferentially into the surface freezing Film. Furthermore, we demonstrated that the freezing transition temperature of cationic surfactant Adsorbed Film was independent of the kind of counterion.

  • miscibility and multilayer formation of fluoroalkane α ω diol mixtures at the air water interface
    Journal of Physical Chemistry B, 2011
    Co-Authors: Takanori Takiue, Hiroki Matsubara, Hiroyasu Sakamoto, Fumiya Nakamura, Makoto Aratono
    Abstract:

    The surface tension γ of the aqueous solution of 1H,1H,6H,6H-perfluorohexane−1,6-diol (FC6diol) and 1H,1H,8H,8H-perfluorooctane−1,8-diol (FC8diol) mixtures was measured as a function of total molality m and composition of FC8diol in the mixture X2 at 293.15 K under atmospheric pressure. The γ vs m curves except at X2 = 0 and 0.05 have a distinct break point due to a phase transition in the Adsorbed Film. The surface pressure π vs mean area per Adsorbed molecule A curves consist of two parts connected by a discontinuous change. The curve was almost vertical just below the phase transition, and the variation of the A value with Film composition X2H was linear corresponding to the fact that FC6diol and FC8diol molecules orient parallel to the surface and are densely packed with the same areas of individual condensed Films. Above the phase transition, the A value further decreases to around 0.12−0.19 nm2 which is much smaller than the cross-sectional area of the fluorocarbon chain, indicating the multilayer f...

  • surface adsorption and aggregate formation of aqueous binary mixture of cationic surfactant and sugar surfactant
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2008
    Co-Authors: Hiroki Matsubara, Takanori Takiue, H Obata, Takashi Matsuda, Makoto Aratono
    Abstract:

    Abstract The surface tension of aqueous solutions of dodecyltrimethylammonium bromide (DTAB) and octyl-β- d -glucopyranoside (OG) mixture was measured as a function of the total molality of surfactants and the relative proportion of OG under atmospheric pressure at 298.15 K by drop volume technique. The results of surface tension measurements were analyzed by originally developed thermodynamic equations then phase diagrams of adsorption and micelle formation were constructed. From the analysis of surface tension data, it was suggested that the addition of relatively small amount of DTAB molecules helps the denser monolayer formation compared with the ideal mixing. Furthermore, it was also suggested that the phase diagram of micelle formation has a negative azeotropic point and that the interaction between different components is stronger in the mixed micelle than in the Adsorbed Film from the view point of the excess Gibbs energy. From these results, it is concluded that the hydrogen bond formation between OG molecules is the main contribution to determine the physical properties in the Adsorbed Film whereas the ion–dipole interaction between head groups of different components becomes main cause of attractive interaction in the micelle.

Hiroki Matsubara - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Surface Freezing on Stability of Oil-in-Water Emulsions
    2018
    Co-Authors: Yuhei Tokiwa, Takanori Takiue, Makoto Aratono, Hiroki Matsubara, Hiromu Sakamoto, Colin D. Bain
    Abstract:

    Penetration of alkane molecules into the Adsorbed Film of a cationic surfactant gives rise to a surface freezing transition at the alkane–water interface upon cooling. In this paper, we show that surface freezing of hexadecyl­trimethyl­ammonium chloride (CTAC) at the tetradecane–water interface stabilizes oil-in-water (OW) emulsions. For concentrations of CTAC near the critical micelle concentration, an OW emulsion coalesced readily above the surface freezing transition whereas the OW emulsion was stable in the surface frozen state. There was a discontinuous change in the stability of the OW emulsion at a temperature very close to the surface phase transition temperature as determined by interfacial tensiometry and ellipsometry on a planar oil–water interface. The mechanical elasticity of the surface frozen layer opposes Film drainage and density fluctuations that could lead to rupture and is the most likely cause of the enhanced emulsion stability

  • Adsorbed Film of n tetradecylphosphocholine at the tetradecane water interface studied by interfacial tensiometry and x ray reflection
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015
    Co-Authors: Shinya Hiraki, Makoto Aratono, Hiroki Matsubara, Toshiaki Ina, Kiyofumi Nitta, Hajime Tanida, Tomoya Uruga, T Goto, Takanori Takiue
    Abstract:

    Abstract The Adsorbed Film of n-tetradecylphosphocholine (C14PC) at the tetradecane (C14)/aqueous solution (W) interface was studied by interfacial tensiometry and X-ray reflection (XR). The interfacial tension γ was measured as a function of molality m C 14 PC and temperature T under atmospheric pressure. The interfacial density of C14PC Γ C 14 PC H increases with increasing m C 14 PC and converges into 3 μmol m−2 (first saturation) at m C 14 PC ≈ 0.08 mmol kg − 1 and into 4.2 μmol m−2 (second saturation) at the critical micelle concentration (CMC). The electron density profile determined by XR indicated that C14PC molecules form monolayer with relatively loose packing at the first saturation. In the second saturation, on the other hand, the molecules form bilayer in which charge separated phosphocholine groups take upside-down arrangement to interact attractively between neighbors. The positive entropy changes associated with adsorption both from monomeric and from micellar states result from that the contribution of dehydration around C14PC molecules, especially around PC groups, by the adsorption from aqueous solution overcomes that of a comparatively ordered molecular orientation at the interface. By comparing the results at the C14/W interface with those at the Air (A)/W one, it was shown that in the monolayer and bilayer states, hydrophobic chains of C14PC molecules are more ordered at the C14/W than at the A/W interface because of attractive interaction between C14PC and C14 molecules. This leads to smaller value of the partial molar entropy and energy changes associated with the adsorption at the C14/W than at the A/W interface. Furthermore the entropy of micelle formation changes from positive to negative with increasing T, suggesting that the entropy gain due to the dehydration exceeds the entropy loss by the aggregation at low temperatures, while the gain is less than the loss at high temperature.

  • effect of alkane chain length and counterion on the freezing transition of cationic surfactant Adsorbed Film at alkane mixture water interfaces
    Journal of Physical Chemistry B, 2015
    Co-Authors: Yuhei Tokiwa, Takanori Takiue, Makoto Aratono, Hiroyasu Sakamoto, Hiroki Matsubara
    Abstract:

    Penetration of alkane molecules into the Adsorbed Film gives rise to a surface freezing transition of cationic surfactant at the alkane–water interface. To examine the effect of the alkane chain length and counterion on the surface freezing, we employed interfacial tensiometry and ellipsometry to study the interface of cetyltrimethylammonium bromide and cetyltrimethylammonium chloride aqueous solutions against dodecane, tetradecane, hexadecane, and their mixtures. Applying theoretical equations to the experimental results obtained, we found that the alkane molecules that have the same chain length as the surfactant adsorb preferentially into the surface freezing Film. Furthermore, we demonstrated that the freezing transition temperature of cationic surfactant Adsorbed Film was independent of the kind of counterion.

  • miscibility and multilayer formation of fluoroalkane α ω diol mixtures at the air water interface
    Journal of Physical Chemistry B, 2011
    Co-Authors: Takanori Takiue, Hiroki Matsubara, Hiroyasu Sakamoto, Fumiya Nakamura, Makoto Aratono
    Abstract:

    The surface tension γ of the aqueous solution of 1H,1H,6H,6H-perfluorohexane−1,6-diol (FC6diol) and 1H,1H,8H,8H-perfluorooctane−1,8-diol (FC8diol) mixtures was measured as a function of total molality m and composition of FC8diol in the mixture X2 at 293.15 K under atmospheric pressure. The γ vs m curves except at X2 = 0 and 0.05 have a distinct break point due to a phase transition in the Adsorbed Film. The surface pressure π vs mean area per Adsorbed molecule A curves consist of two parts connected by a discontinuous change. The curve was almost vertical just below the phase transition, and the variation of the A value with Film composition X2H was linear corresponding to the fact that FC6diol and FC8diol molecules orient parallel to the surface and are densely packed with the same areas of individual condensed Films. Above the phase transition, the A value further decreases to around 0.12−0.19 nm2 which is much smaller than the cross-sectional area of the fluorocarbon chain, indicating the multilayer f...

  • surface adsorption and aggregate formation of aqueous binary mixture of cationic surfactant and sugar surfactant
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2008
    Co-Authors: Hiroki Matsubara, Takanori Takiue, H Obata, Takashi Matsuda, Makoto Aratono
    Abstract:

    Abstract The surface tension of aqueous solutions of dodecyltrimethylammonium bromide (DTAB) and octyl-β- d -glucopyranoside (OG) mixture was measured as a function of the total molality of surfactants and the relative proportion of OG under atmospheric pressure at 298.15 K by drop volume technique. The results of surface tension measurements were analyzed by originally developed thermodynamic equations then phase diagrams of adsorption and micelle formation were constructed. From the analysis of surface tension data, it was suggested that the addition of relatively small amount of DTAB molecules helps the denser monolayer formation compared with the ideal mixing. Furthermore, it was also suggested that the phase diagram of micelle formation has a negative azeotropic point and that the interaction between different components is stronger in the mixed micelle than in the Adsorbed Film from the view point of the excess Gibbs energy. From these results, it is concluded that the hydrogen bond formation between OG molecules is the main contribution to determine the physical properties in the Adsorbed Film whereas the ion–dipole interaction between head groups of different components becomes main cause of attractive interaction in the micelle.

Takanori Takiue - One of the best experts on this subject based on the ideXlab platform.

  • solid Film formation at the tetradecane aqueous hexadecyltrimethylammonium bromide solution interface studied by interfacial tensiometry and x ray reflectometry
    Journal of Physical Chemistry B, 2019
    Co-Authors: Haruna Hayase, Yosuke Imai, Toshiaki Ina, Kiyofumi Nitta, Hajime Tanida, Tomoya Uruga, Takanori Takiue
    Abstract:

    The effect of oil on condensed Film formation in the Adsorbed Film of hexadecyltrimethylammonium bromide (C16TAB) at the tetradecane (C14)/water (W) interface was examined by interfacial tension and X-ray reflectivity measurements. The interfacial tension vs temperature curves have break point due to the expanded?condensed phase transition of the Adsorbed Film. The partial molar entropy of C16TAB at the interface changes discontinuously, whereas the interfacial density changes almost continuously at the phase transition point. The electron density profile normal to the interface manifested that the condensed Film is regarded as a two-dimensional (2D) solid rotator phase in which C16TAB and C14 molecules are densely packed with perpendicular orientation. Combining the interfacial tension and X-ray reflectivity data, the mixing ratio of C16TAB to C14 in the solid Film was determined to be 2:3 and thus the Film is enriched in oil molecules than surfactant ones. Furthermore, the partial molar entropy change of C14 associated with solid Film formation was found to be largely negative and very close to that of surface freezing of liquid alkane, manifesting that C14 molecules are well ordered to form a 2D solid Film by mixing with C16TAB molecules at the interface. The solid Film formation of the present system is driven by effective vdW interactions between Adsorbed C16TAB and intercalated C14 molecules. The morphology of the condensed domain observed during phase transition suggested that the contact energy is more predominant than the dipole repulsion at the domain boundary, which promotes coalescence of small domains into large ones during phase transition.

  • Effect of Surface Freezing on Stability of Oil-in-Water Emulsions
    2018
    Co-Authors: Yuhei Tokiwa, Takanori Takiue, Makoto Aratono, Hiroki Matsubara, Hiromu Sakamoto, Colin D. Bain
    Abstract:

    Penetration of alkane molecules into the Adsorbed Film of a cationic surfactant gives rise to a surface freezing transition at the alkane–water interface upon cooling. In this paper, we show that surface freezing of hexadecyl­trimethyl­ammonium chloride (CTAC) at the tetradecane–water interface stabilizes oil-in-water (OW) emulsions. For concentrations of CTAC near the critical micelle concentration, an OW emulsion coalesced readily above the surface freezing transition whereas the OW emulsion was stable in the surface frozen state. There was a discontinuous change in the stability of the OW emulsion at a temperature very close to the surface phase transition temperature as determined by interfacial tensiometry and ellipsometry on a planar oil–water interface. The mechanical elasticity of the surface frozen layer opposes Film drainage and density fluctuations that could lead to rupture and is the most likely cause of the enhanced emulsion stability

  • Adsorbed Film of n tetradecylphosphocholine at the tetradecane water interface studied by interfacial tensiometry and x ray reflection
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015
    Co-Authors: Shinya Hiraki, Makoto Aratono, Hiroki Matsubara, Toshiaki Ina, Kiyofumi Nitta, Hajime Tanida, Tomoya Uruga, T Goto, Takanori Takiue
    Abstract:

    Abstract The Adsorbed Film of n-tetradecylphosphocholine (C14PC) at the tetradecane (C14)/aqueous solution (W) interface was studied by interfacial tensiometry and X-ray reflection (XR). The interfacial tension γ was measured as a function of molality m C 14 PC and temperature T under atmospheric pressure. The interfacial density of C14PC Γ C 14 PC H increases with increasing m C 14 PC and converges into 3 μmol m−2 (first saturation) at m C 14 PC ≈ 0.08 mmol kg − 1 and into 4.2 μmol m−2 (second saturation) at the critical micelle concentration (CMC). The electron density profile determined by XR indicated that C14PC molecules form monolayer with relatively loose packing at the first saturation. In the second saturation, on the other hand, the molecules form bilayer in which charge separated phosphocholine groups take upside-down arrangement to interact attractively between neighbors. The positive entropy changes associated with adsorption both from monomeric and from micellar states result from that the contribution of dehydration around C14PC molecules, especially around PC groups, by the adsorption from aqueous solution overcomes that of a comparatively ordered molecular orientation at the interface. By comparing the results at the C14/W interface with those at the Air (A)/W one, it was shown that in the monolayer and bilayer states, hydrophobic chains of C14PC molecules are more ordered at the C14/W than at the A/W interface because of attractive interaction between C14PC and C14 molecules. This leads to smaller value of the partial molar entropy and energy changes associated with the adsorption at the C14/W than at the A/W interface. Furthermore the entropy of micelle formation changes from positive to negative with increasing T, suggesting that the entropy gain due to the dehydration exceeds the entropy loss by the aggregation at low temperatures, while the gain is less than the loss at high temperature.

  • effect of alkane chain length and counterion on the freezing transition of cationic surfactant Adsorbed Film at alkane mixture water interfaces
    Journal of Physical Chemistry B, 2015
    Co-Authors: Yuhei Tokiwa, Takanori Takiue, Makoto Aratono, Hiroyasu Sakamoto, Hiroki Matsubara
    Abstract:

    Penetration of alkane molecules into the Adsorbed Film gives rise to a surface freezing transition of cationic surfactant at the alkane–water interface. To examine the effect of the alkane chain length and counterion on the surface freezing, we employed interfacial tensiometry and ellipsometry to study the interface of cetyltrimethylammonium bromide and cetyltrimethylammonium chloride aqueous solutions against dodecane, tetradecane, hexadecane, and their mixtures. Applying theoretical equations to the experimental results obtained, we found that the alkane molecules that have the same chain length as the surfactant adsorb preferentially into the surface freezing Film. Furthermore, we demonstrated that the freezing transition temperature of cationic surfactant Adsorbed Film was independent of the kind of counterion.

  • miscibility and multilayer formation of fluoroalkane α ω diol mixtures at the air water interface
    Journal of Physical Chemistry B, 2011
    Co-Authors: Takanori Takiue, Hiroki Matsubara, Hiroyasu Sakamoto, Fumiya Nakamura, Makoto Aratono
    Abstract:

    The surface tension γ of the aqueous solution of 1H,1H,6H,6H-perfluorohexane−1,6-diol (FC6diol) and 1H,1H,8H,8H-perfluorooctane−1,8-diol (FC8diol) mixtures was measured as a function of total molality m and composition of FC8diol in the mixture X2 at 293.15 K under atmospheric pressure. The γ vs m curves except at X2 = 0 and 0.05 have a distinct break point due to a phase transition in the Adsorbed Film. The surface pressure π vs mean area per Adsorbed molecule A curves consist of two parts connected by a discontinuous change. The curve was almost vertical just below the phase transition, and the variation of the A value with Film composition X2H was linear corresponding to the fact that FC6diol and FC8diol molecules orient parallel to the surface and are densely packed with the same areas of individual condensed Films. Above the phase transition, the A value further decreases to around 0.12−0.19 nm2 which is much smaller than the cross-sectional area of the fluorocarbon chain, indicating the multilayer f...

Norihiro Ikeda - One of the best experts on this subject based on the ideXlab platform.

  • surface density measurement of the bromide ion by the total reflection x ray absorption fine structure technique at the air aqueous dodecyltrimethylammonium bromide solution interface
    Langmuir, 2003
    Co-Authors: Takanori Takiue, Norihiro Ikeda, Makoto Aratono, Hajime Tanida, Yasuhiro Kawagoe, Soichiro Muroi, Ryo Murakami, Hideto Sakane, Makoto Harada, Iwao Watanabe
    Abstract:

    The X-ray absorption fine structure technique was applied to the aqueous dodecyltrimethylammonium bromide solution surface under the total reflection condition at 275 K. The Br K-edge absorption jump (J) value was evaluated and compared to the surface density (Γ H 1) of surfactants calculated from the surface tension versus concentration curve at 275.15 K. An excellent correlation between the J and Γ H 1 values was found, and their dependences on concentration were not of a simple Langmuir type but of the Frumkin type. This should be indicative that a phase transition between the gaseous and expanded states takes place in the Adsorbed Film, claimed previously by us. Furthermore, the J value shows a stepwise increase at around the critical micelle concentration (cmc). This may be attributed to a change of the structure of the Adsorbed Film, such as staggered arrangement of surfactant ions close to the cmc to minimize the electric repulsion between their headgroups, or that of the electrical double layer. The results obtained in this study are compared to those evaluated from the radiotracer method applied to the aqueous tritiated sodium dodecyl sulfate solution surface.

  • interfacial Films and wetting behavior of hexadecane on aqueous solutions of dodecyltrimethylammonium bromide
    Langmuir, 2003
    Co-Authors: Hiroki Matsubara, Norihiro Ikeda, Takanori Takiue, Makoto Aratono, Colin D Bain
    Abstract:

    The interfacial tensions and dihedral angles of hexadecane lenses on aqueous solutions of dodecyltrimethylammonium bromide (DTAB) were measured in air as a function of the molality of DTAB at 298.15 K and atmospheric pressure. The air/water interfacial tension of DTAB solution shows a break point that shifts to a lower concentration in the presence of a hexadecane lens. Ellipsometric measurements showed a continuous variation in ellipticity with concentration for pure DTAB solutions, but a discontinuous change in the ellipticity of the air/water interface in the presence of a hexadecane lens. This behavior can be viewed either as a first-order wetting transition driven by the Adsorbed surfactant, or as a gaseous-expanded phase transition in the surfactant Adsorbed Film induced by the hexadecane. The formation of a microscopic oil Film in equilibrium with a lens is rationalized by an attractive long-range potential across the thin Film. From the measurement of dihedral angles, it was found that there was a...

  • interaction between ionic and nonionic surfactants in the Adsorbed Film and micelle 3 sodium dodecyl sulfate and tetraethylene glycol monooctyl ether
    Langmuir, 2001
    Co-Authors: Hiroki Matsubara, Norihiro Ikeda, Mitsuhiro Kameda, Soichiro Muroi, And Akio Ohta, Makoto Aratono
    Abstract:

    The surface tension of the aqueous solutions of sodium dodecyl sulfate (SDS) and tetraethylene glycol monooctyl ether (C8E4) was measured as a function of the total molality of the surfactants and the composition of C8E4 at constant temperature under atmospheric pressure. The results of the surface tension measurement were analyzed by our thermodynamic procedure. Both the phase diagram of adsorption and that of micelle formation were found to have an azeotropic point, and the stronger energetic stabilization was suggested. The extent of this nonideal mixing was estimated quantitatively in terms of the excess Gibbs energy, ĝH,E, in the Adsorbed Film and of that in the micelle, ĝM,E. The dependence of ĝH,E on the surface tension was also utilized to elucidate the mechanism of the attraction between the different species in these aggregates in detail. By combining the results of the present study with that of the previous one, we concluded that the attractive interaction acting in the Adsorbed Film and micel...

  • interaction between ionic and nonionic surfactants in the Adsorbed Film and micelle dodecylammonium chloride and tetraethylene glycol monooctyl ether
    Langmuir, 2000
    Co-Authors: Hiroki Matsubara, Norihiro Ikeda, Akio Ohta, Mitsuhiro Kameda, Makoto Aratono
    Abstract:

    The surface tension of aqueous solutions of dodecylammonium chloride (DAC) and tetraethylene glycol monooctyl ether (C8E4) was measured as a function of the total molality of surfactants and the composition of C8E4 at constant temperature under atmospheric pressure. The results of the surface tension measurements were analyzed by our thermodynamic procedure, and phase diagrams of adsorption and micelle formation were drawn. The miscibility of the surfactants and their intermolecular interaction in both the Adsorbed Film and the micelles were examined. Deviation from ideal mixing was observed and an attractive interaction was suggested. Furthermore, the phase diagram of micelle formation was shown to have an azeotropic point, and a stronger energetic stabilization was suggested in the mixed micelle formation than in the Adsorbed Film at the cmc. This difference suggests that the structures of both the surfactant molecules and the aggregates significantly affect the intermolecular interaction between surfac...

  • interaction between ionic and nonionic surfactants in the Adsorbed Film and micelle hydrochloric acid sodium chloride and tetraethylene glycol monooctyl ether
    Langmuir, 1999
    Co-Authors: Hiroki Matsubara, Norihiro Ikeda, Akio Ohta, Mitsuhiro Kameda, Masumi Villeneuve, Makoto Aratono
    Abstract:

    The aqueous solutions of hydrochloric acid−tetraethylene glycol monooctyl ether (C8E4) and sodium chloride−C8E4 mixtures were investigated to examine the interaction between inorganic ions and noni...

Mitsuhiro Kameda - One of the best experts on this subject based on the ideXlab platform.