M. Maugey et Am. Bellocq, Effect of added salt and poly(ethylene glycol) on the phase behavior of a balanced AOT-water-oil system, LANGMUIR, 15(25), 1999, pp. 8602-8608
The phase behavior of AOT-water-NaCl-poly(ethylene glycol) (PEG; M-w = 20 0
00) - isooctane mixtures at equal volumes of water and oil has been systema
tically explored as a function of AOT, NaCl, and PEG concentrations. The ef
fect of adding PEG is in many respects similar to that of adding salt altho
ugh the changes are less pronounced. Each additive, taken separately, shift
s the phase behavior to higher temperature, promotes the formation of bicon
tinuous microemulsions, and induces a lamellar-to-bicontinuous microemulsio
n phase transition. The simultaneous presence of both additives enhances th
e effect of salt. These phase behavior results suggest that the two variabl
es salt and PEG act in the same direction on the spontaneous curvature C-0,
the bending rigidity kappa, and the Gaussian bending modulus <(kappa)over
bar> of the AOT monolayer.