RT info:eu-repo/semantics/article
T1 Dielectric and refractive index measurements for the systems 1-pentanol + 2,5,8,11,14-pentaoxapentadecane, or for 2,5,8,11,14-pentaoxapentadecane + octane at (293.15-303.15) K
A1 Alonso Gómez, Víctor
A1 González López, Juan Antonio Mariano
A1 García de la Fuente, Isaías Laudelino
A1 Cobos Hernández, José Carlos
AB Relative permittivities,   , and refractive indices,  , have been measured at (293.15-303.15) K, for the mixtures 1-pentanol + 2,5,8,11,14-pentaoxapentadecane (TEGDME) or TEGDME + octane. These data have been used, together with density measurements available in the literature, to calculate the correlation factors, , according to the Kirkwood-Fröhlich equations. The  curves of the deviations of   from the ideal behaviour,  , of the 1-pentanol + TEGDME system are shifted to high mole fractions of the alcohol, and show a rather large minimum. The shape of the   curves of methanol + TEGDME or + polyethylene glycol dimethyl ether 250 (PEG-250) mixtures is similar. This reveals that polyethers can break the alcohol self-association even at high alkanol concentrations. The higher  values of the methanol solutions are ascribed to large self-association of this alcohol.  The   curves of the 1-pentanol + dibutyl ether (DBE) system are nearly symmetrical, and the   values are higher than those of the corresponding TEGDME mixture. This indicates that effects related to the alcohol self-association are much more relevant in the DBE system. These findings are supported by  and molar polarization data. Values of molar refraction of 1-pentanol systems reveal that dispersion forces become more important in the sequence: octane < DBE < TEGDME. Such forces are also more relevant in the 1-pentanol + TEGDME system than in the methanol + TEGDME solution.  The comparison of   and   data for TEGDME or DBE + octane mixtures shows than the polyether is a more structured liquid.
YR 2013
FD 2013
LK https://uvadoc.uva.es/handle/10324/66122
UL https://uvadoc.uva.es/handle/10324/66122
LA eng
NO Thermochimica Acta, 2013, 551, 70-77
DS UVaDOC
RD 24-nov-2024