Thermodynamics of Mixtures Containing Alkoxyethanols. XXI. Application of the Flory Theory to the Study of Orientational Effects in Systems with Dibutyl Ether or 1-Butanol
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- 作者：J. A. Gonzá ; lez ; N. Riesco ; I. Mozo ; I. Garcí ; a De La Fuente ; J. C. Cobos
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2007
- 出版时间：February 14, 2007
- 年：2007
- 卷：46
- 期：4
- 页码：1350 - 1359
- 全文大小：130K
- 年卷期：v.46,no.4(February 14, 2007)
- ISSN：1520-5045
文摘
The physical meaning of the energetic parameter, 
12, that is characteristic of Flory theory is explored inconnection to the random mixing hypothesis. It is known that, if such a hypothesis is valid, 12 is independentof the concentration (x1). Here, deviations from the random mixing hypothesis are attributed to an excess ofinteractions between like molecules (if 12(x1) > 12(x1 = 0.5)) or of interactions between unlike molecules(if 12(x1) < 12(x1 = 0.5)). Binary mixtures of the type hydroxyether + dibutyl ether, or + 1-alkanol, or +2-methoxyethanol have been investigated studying the 12 variation with x1. Toward this end, we provide anew expression for 12 which makes possible the exact determination of this magnitude at any compositionif the corresponding molar excess enthalpy, 
journals/iecred/46/i04/eqn/ie0609012e10001.gif">, is known. Orientational effects are present in the studiedsolutions, although the model can represent the journals/iecred/46/i04/eqn/ie0609012e10002.gif"> for hydroxyether + 1-alkanol or + 2-methoxyethanol,where the mentioned effects are weaker. The excess molar volumes, journals/iecred/46/i04/eqn/ie0609012e10003.gif">, are only described for the systemswith two cellosolves, due to the existence in the remainder mixtures of structural effects. Results from theKirkwood-Buff formalism, applied to 2-ethoxyethanol + dibutyl ether, or + 1-butanol, systems are inagreement with those obtained using Flory theory.
12, that is characteristic of Flory theory is explored inconnection to the random mixing hypothesis. It is known that, if such a hypothesis is valid, 12 is independentof the concentration (x1). Here, deviations from the random mixing hypothesis are attributed to an excess ofinteractions between like molecules (if 12(x1) > 12(x1 = 0.5)) or of interactions between unlike molecules(if 12(x1) < 12(x1 = 0.5)). Binary mixtures of the type hydroxyether + dibutyl ether, or + 1-alkanol, or +2-methoxyethanol have been investigated studying the 12 variation with x1. Toward this end, we provide anew expression for 12 which makes possible the exact determination of this magnitude at any compositionif the corresponding molar excess enthalpy,