| Abstract
| - In the present work, we have studied the influence of a water-soluble neutral polymer (poly-N-vinyl pyrrolidin-2-one, PVP) on the Kamlet−Taft polarity parameters of sodium n-dodecyl sulfate (SDS) micelles. We haveused pyrene as an independent dipolarity/polarizability (π* parameter) descriptor molecule. It has been foundthat the addition of polymer (0.1 wt % PVP) increases the π* value of SDS micelles, suggesting thatPVP−SDS aggregates have a larger dipolarity/polarizability than that of SDS micelles. Linear solvation energyrelationships involving the fluorescence transition energy of four structurally similar ketocyanine dyes havealso been used to evaluate the polarity parameters. It is interesting to observe that the addition of polymerleads to a decrease in both the hydrogen-bond donation (α-parameter) and hydrogen-bond acceptance ability(β-parameter) of the micellar aggregate formed by PVP−SDS, whereas the dipolarity/polarizability valueshows an increasing trend. Moreover, convergent results have been obtained for the π* value for PVP−SDSaggregates, using pyrene as a π* descriptor and ketocyanine dyes as molecular probes.
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