Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Thermodynamics of Micellization of Alkyldimethylbenzylammonium Chlorides in Aqueous Solutions
Ist Teil von
Journal of colloid and interface science, 2002-06, Vol.250 (2), p.438-443
Ort / Verlag
San Diego, CA: Elsevier Inc
Erscheinungsjahr
2002
Quelle
Alma/SFX Local Collection
Beschreibungen/Notizen
Specific conductivities of alkyldimethylbenzylammonium chlorides (alkyl=decyl-, dodecyl-, tetradecyl-, and hexadecyl-) in aqueous solutions were measured as a function of molality and temperature. Critical micelle molalities (cmc) and degrees of ionization of the micelles, β, were estimated from the dependence of the specific conductivity on molality. It was found that temperature dependence of cmc is U-shaped with a minimum shifting toward higher temperatures with a decrease in the chain length of the alkyl group. The temperature dependence of ln xcmc (where xcmc is the cmc in mole fraction units) was fitted to the equation of Muller, which we modified by taking into account the temperature dependencies both of β and of change in heat capacity upon micellization. From the fitting parameters, Gibbs free energies, enthalpies, and entropies of micellization as a function of temperature were estimated.