Anomalous Dynamics of Solutions of Nonionic Micelles in Water

Abstract

In addition to a previous theory on the coupling between noncritical concentration fluctuations and elementary chemical processes, an alternative treatment is presented which allows for a closed-form solution of ultrasonic attenuation spectra. This analytical form is first compared to a previous model and also to experimental spectra of binary liquid mixtures. The broadening of the spectra is briefly discussed in terms of molecular interactions and of the ratio of the relaxation times of the chemical equilibrium and of the diffusion of fluctuations. Extension of the theoretical model to apply to nonionic micelle solutions reveals that a flat contribution in the experimental spectra of such quasi-ternary systems may be simply due to different structure factors of the monomers and the micelles. Some exceptional findings for polyethylene glycol monoalkyl ether/water mixtures are discussed in light of the theory.