Partition coefficients of homologous .omega.-phenylalkanols between water and sodium dodecyl sulfate micelles

Abstract

The partition coefficient, K, of w-phenylalkanols (C6HS(CH2)90H, mp = 0-6) between the bulk water and micelles of sodium dodecyl sulfate (SDS) was determined at 25 O C by a differential spectroscopic method. A new approach for the determination of K has been proposed, taking both the effect of added alkanol on the concentration of monomerically dissolved surfactant in micellar solutions and the fraction of the amount of solubiiized alkanol in that of added alkanol into account, K is found to be independent of the concentration of SDS from just above the critical micelle concentration to high concentration, as well as the concentration of added alkanols. The linear dependence of the free energy change on the alkyl chain length of the alkanols (mP 2 3) on solubilization in micelles calculated from K makes it clear that the contribution of a methylene group to the free energy change is -2.40 k J mol-' in accord with the corresponding value for I-alkanols and that the hydrophobicity of the phenyl group corresponds to that of 3.5 methylene groups. The interaction of the phenylalkanols with SDS has also been discussed. (9) Treiner, C.; Chattopadhyay, A. K.; Bury, R. J. Colloid Interfuce Sci. 1985, 104, 569.

Interaction of Azo Dye with Cationic Surfactant Under Different pH Conditions

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Study of valsartan interaction with micelles as a model system for biomembranes

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Effect of Hydroxyl Groups on Solubilization States of Alkandiols in DTAB Micelles: Application of a Differential Conductivity Technique

“…The standard Gibbs energy change of transfer per methylene group, ΔG 0 CH 2 , was calculated from the slope of the straight line in Fig. 9 based on the following equation 12 ,…”