You are in the accessibility menu

Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorSwanson-Vethamuthu, M.-
dc.contributor.authorFeitosa, E.-
dc.contributor.authorBrown, W.-
dc.identifier.citationLangmuir. Washington: Amer Chemical Soc, v. 14, n. 7, p. 1590-1596, 1998.-
dc.description.abstractWe have used surface tension measurements, differential scanning calorimetry (DSC), dynamic light scattering (DLS), and cryo-transmission electron microscopy (cryo-TEM) to investigate the dynamic and structural behavior of octadecyltrimethylammonium bromide (C(18)TAB) micelles in water and NaBr solution. The surface tension data for fixed C(18)TAB concentrations of 25 mM and varied NaBr additions (0-50 mM) shows that the critical micelle concentration (cmc) increases after an initial decrease at 0.5 mM NaBr. This unusual effect has been explained using results from DSC and DLS. At low salt concentrations (below ca. 25 mM) the relaxation time distribution is bimodal with a dominant fast mode due to spherical micelles. Above ca. 35 mM NaBr disklike structures are favored and the relaxation time distribution is more closely unimodal. The postulated sphere-to-disk transition is supported by cryo-TEM micrographs. A pronounced increase in the micellar effective hydrodynamic radius (R-H) is observed as the NaBr concentration is increased above about 35 mM; below 35 mM the R-H of the spherical micelles changes Little with ionic strength.en
dc.publisherAmer Chemical Soc-
dc.sourceWeb of Science-
dc.titleSalt-induced sphere-to-disk transition of octadecyltrimethylammonium bromide micellesen
dc.contributor.institutionUniversidade Estadual Paulista (UNESP)-
dc.contributor.institutionUniv Uppsala-
dc.description.affiliationUNESP, IBILCE, Dept Fis, Sao Jose Rio Preto, SP, Brazil-
dc.description.affiliationUniv Uppsala, Dept Phys Chem, S-75121 Uppsala, Sweden-
dc.description.affiliationUnespUNESP, IBILCE, Dept Fis, Sao Jose Rio Preto, SP, Brazil-
dc.rights.accessRightsAcesso restrito-
Appears in Collections:Artigos, TCCs, Teses e Dissertações da Unesp

There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.