Combined effect of temperature and electrolyte on triton X-100 micellar diffusion

The self-diffusion coefficients (Ds) of Triton X-100 micelles have been determined voltammetrically as a function of KCl concentration and temperature. Normalised diffusion coefficients (Dsηo/T) were found to decrease linearly with increasing [KCl] at fixed temperatures over the range 288–313 K due to electrolyte induced micellar growth. Dsηo/T was also found to decrease with increasing temperature due to temperature-induced micellar growth although the temperature-dependent intermicellar interaction parameters were found to decrease with increasing temperature suggesting increasing attractive interactions at higher temperatures where as the interaction parameter increases with [KCl]. An electrolyte concentration dependent transition (suppression of Dsηo/T) was observed at temperatures below the onset of extensive micellar growth and appears to be unrelated to the usual phase separation behaviour frequently observed and may possibly be related to a significant increase in polydispersity.