Diffusion of water in water-aerosol OT-decane microemulsion

Translational mobility of water molecules was studied in water-Aerosol OT-d ecane microemulsions, The diffusion of individual water microdroplets, wate r in clusters composed of microdroplets, and molecules of water dissolved i n the oil phase was considered. Temperature dependences of the diffusion co efficients of water molecules obtained experimentally by the pulsed-field g radient NMR method were analyzed at high and low contents of the dispersed phase with allowances for structural changes occurring in microemulsion. It was shown that the contribution of water dissolved in oil to the resulting diffusion coefficient is significant at a low content of the dispersed pha se. The dramatic increase in the diffusion rate of water molecules above th e temperature of percolation transition is explained by the increase in the relative fraction of water diffusing through water channels between microd roplets combined into clusters.