APPARENT MOLAR VOLUMES OF SOME HYDROGENATED AND FLUORINATED ALCOHOLS IN SODIUM DODECANOATE AND SODIUM PERFLUOROOCTANOATE AQUEOUS-SOLUTIONS

The apparent molar volumes of some hydrogenated and fluorinated alcoho ls (0.04 in) in sodium perfluorooctanoate and sodium dodecanoate aqueo us solutions were determined as a function of the surfactant concentra tion. With the exception of hexanol in sodium dodecanoate, the apparen t molar volume of alcohols in micellar solutions increases with the su rfactant concentration according to the distribution of the additive b etween the aqueous and the micellar phases. The experimental data were rationalized by using a previously reported model for the additive di stribution between the aqueous and the micellar phases which permits a simultaneous determination of the distribution constant and the parti al molar volume of alcohol in the micellar and aqueous phases. When co mparisons are possible, the present data are, generally, in good agree ment with those reported in the literature. Information on the effect of the nature of the hydrophobic moiety of both the additive and the s urfactant on the additive solubilization in micelles are obtained.