INQUISUR   21779
INSTITUTO DE QUIMICA DEL SUR
Unidad Ejecutora - UE
artículos
Título:
An explanation of experimental results of mixed micelles of homologous surfactants through a MM2 bidimensional modeling
Autor/es:
FERREIRA, M.L., SIERRA, M.B , MORINI, MARCELA, J.L.RODRIGUEZ, R.MINARDI , SCHULZ, P
Revista:
JOURNAL OF PHYSICAL CHEMISTRY B
Editorial:
American Chemical Society
Referencias:
Año: 2010 vol. 114 p. 14924 - 14933
ISSN:
1089-5647
Resumen:
A computational modeling (in gas phase) to study the disposition of the homologous surfactants in a bidimensional simple model of mixed and homogeneous micelles was performed for the case of R-trimethylammonium bromide surfactants with different linear R lengths from R ) C5 to C17. First, the bidimensional homogeneous (one component) micelle was modeled, and as a second step, heterogeneous (two components) bidimensional micelles were modeled. The difference in the number of carbon atoms between hydrocarbon chains of the surfactants in the heterogeneous micelles, ÄnC, ranged from 2 to 8. Results were contrasted with experimental data obtained at our own laboratory. The exothermic values of the steric energy changes showed strong attraction between components of homologous surfactants mixture, especially when one of the surfactants has a long chain. It may be argued that the inclusion of a shorter surfactant in the mixture and the twisting of the longer surfactant makes the bidimensional arrangement formation more exothermic. All predictions were in agreement with previous experimental results.) C5 to C17. First, the bidimensional homogeneous (one component) micelle was modeled, and as a second step, heterogeneous (two components) bidimensional micelles were modeled. The difference in the number of carbon atoms between hydrocarbon chains of the surfactants in the heterogeneous micelles, ÄnC, ranged from 2 to 8. Results were contrasted with experimental data obtained at our own laboratory. The exothermic values of the steric energy changes showed strong attraction between components of homologous surfactants mixture, especially when one of the surfactants has a long chain. It may be argued that the inclusion of a shorter surfactant in the mixture and the twisting of the longer surfactant makes the bidimensional arrangement formation more exothermic. All predictions were in agreement with previous experimental results.