Percolationlike phenomena in oil-continuous microemulsions

Abstract

We have observed in a three-component oil-continuous microemulsion a new percolation phenomenon. The system of interest consists of anionic surfactant-coated water droplets dispersed in oil. The percolation limit ${\phi }_p$ is found to be strongly temperature dependent, while the structure of the microemulsion remains constant. We have proposed a surfactant anion hopping model with a temperature-dependent hopping range. Percolation occurs when the effective droplet volume, as defined by the hopping range, exceeds the hard-sphere close-packing limit of 0.65.