title: Self-association of sodium deoxycholate with EHEC cellulose cooperatively induced by sodium dodecanoate.
abstract: Some aspects of ethyl (hydroxyethyl) cellulose (EHEC) aqueous behavior in the presence of ionic surfactants are described in the literature; however, most of the studies reported address moderately concentrated solutions. Few studies have been carried out in the dilute regime using mixtures of biosurfactants. The main purpose of this work is to investigate the interaction of EHEC in the dilute regime and to verify the mixture of two surfactants: sodium deoxycholate (NaDC) and sodium dodecanoate (SDoD). The parameters of the surfactant to polymer association processes such as the critical aggregation concentration (cac) and saturation of the polymer by surfactants (psp) were determined from the plots of surface tension and specific conductivity versus surfactant concentration in basic conditions. The cmc of NaDC-SDoD mixtures showed non-ideal behavior. However, EHEC added to mixtures of SDoD and NaDC acts as a stabilizer for the mixed aggregate during the association process.
authors.affiliation: Universidade Federal de Santa Catarina, 88040-900, Florianópolis, SC, Brazil.
authors.forename: Samuel de M
authors.initials: Sde M
authors.lastname: Modolon
authors.affiliation: Universidade Federal da Fronteira Sul (UFFS), 89812-000, Chapecó, SC, Brazil.
authors.forename: Arlindo C
authors.initials: AC
authors.lastname: Felippe
authors.affiliation: Universidade do Extremo Sul Catarinense (UNESC), 88806-000 Criciúma, SC, Brazil.
authors.forename: Tiago E
authors.initials: TE
authors.lastname: Fizon
authors.affiliation: Universidade do Extremo Sul Catarinense (UNESC), 88806-000 Criciúma, SC, Brazil.
authors.forename: Luciano
authors.initials: L
authors.lastname: da Silva
authors.affiliation: Universidade do Extremo Sul Catarinense (UNESC), 88806-000 Criciúma, SC, Brazil.
authors.forename: Marcos Marques
authors.initials: MM
authors.lastname: da Silva Paula
authors.affiliation: Universidade do Extremo Sul Catarinense (UNESC), 88806-000 Criciúma, SC, Brazil. Electronic address: adalbo@unesc.net.
authors.forename: Alexandre G
authors.initials: AG
authors.lastname: Dal-Bó
mesh_terms: D002482:Cellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D003840:Deoxycholic Acid / Q000737:chemistry*; D007850:Lauric Acids / Q000737:chemistry*; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D007850:Lauric Acids; D013501:Surface-Active Agents; D003840:Deoxycholic Acid; C030358:lauric acid; D002482:Cellulose; C002283:hydroxyethylcellulose
keywords: Anionic surfactants; Conductivity; Ethyl (hydroxyethyl) cellulose; Polymer–surfactant interaction; Surface tension