Journal of Solution Chemistry

, Volume 22, Issue 10, pp 941–949 | Cite as

Refractive index of water-AOT-n-heptane microemulsions

  • M. Goffredi
  • V. Turco Liveri
  • G. Vassallo


Refractive index measurements on water/AOT/n-heptane microemulsions as a function of the volume fraction ϕ of the dispersed phase (water plus AOT) and of the water/AOT molar ratio R have been performed at 25°C. The refractive index was found to vary monotonically with ϕ without any change in rate during the crossover of the percolation threshold. Such a behavior suggested that, well above the percolation threshold, the water-AOT-n-heptane microemulsions are still formed by water-containing AOT reversed micelles dispersed in the oil phase. The analysis of the experimental data allowed an evaluation the fraction of the water molecules bonded to the AOT head group as a function of R.

Key Words

Reversed AOT micelles refractive index percolation 


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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • M. Goffredi
    • 1
  • V. Turco Liveri
    • 1
  • G. Vassallo
    • 1
  1. 1.Department of Physical ChemistryUniversity of PalermoPalermoItaly

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