n-Hexanol association in cyclohexane studied by NMR and NIR spectroscopies

Flores, ME; Shibue T.; Sugimura, N; Nishide H.; Martinez F.; Olea, AF; Moreno-Villoslada, I

Keywords: nmr, nir, Alcohol self-association, Water-in-oil microemulsions

Abstract

In this work we present a study on the association of n-hexanol in cyclohexane using NMR and NIR spectroscopies. Abrupt changes on spectroscopic responses have been observed at low molar fractions of n-hexanol, which are related to hydrogen bond network formation that includes trace water. Molecular interactions are found to be dominated by dispersion forces, hydrogen bonding, and dipolar interactions, to different extents at different n-hexanol composition ranges. 1D, DOSY, and T-1 and T-2 relaxation time analyses by H-1-NMR allow understanding the dynamics of the mixtures. NIR allows verifying the formation of n-hexanol polymeric species. In addition, an n-hexanol/cyclohexane mixture with an alcohol molar fraction of 0.177 has been titrated with water, revealing the formation of a microemulsion containing water droplets that evolves to a bicontinuous microemulsion with increasing water content. Stable boundary water is detected at the microemulsion interface. (C) 2014 Elsevier B.V. All rights reserved.

Más información

Título según WOS: n-Hexanol association in cyclohexane studied by NMR and NIR spectroscopies
Título según SCOPUS: N-Hexanol association in cyclohexane studied by NMR and NIR spectroscopies
Título de la Revista: JOURNAL OF MOLECULAR LIQUIDS
Volumen: 199
Editorial: Elsevier
Fecha de publicación: 2014
Página de inicio: 301
Página final: 308
Idioma: English
DOI:

10.1016/j.molliq.2014.09.012

Notas: ISI, SCOPUS