Actually the concentration of water in modified gasoline increases with an increase in the surfactant concentration.However, the content of water in gasoline modified with
alcohols (5% v/v) is lower in comparison with basic gasoline.That atypical behaviour can be explained with two opposite effects. An addition of hydrophilic additives
increases the polarity of gasoline and enhances the solubility of water. However, when used in large amounts, the additives do not work as co-surfactants and they retard
association of surfactants, i.e. the formation of swollen reversed micelles with water pools in micelle cores. The second effect is dominant when methanol and ethanol are used
as modifiers. These alcohols have low molecular weights and they do not build into the micelles. As a result, the solubility of water in such modified gasoline is low and
increases only slightly with an increase in the surfactant concentration.