Bicontinuous microemulsions with extremely high temperature stability based on skin friendly oil and sugar surfactant

In the present article the phase behavior of microemulsions based on isononyl isononanoate (Lanol 99), sugar surfactant Simulsol SL55 (C12/14G1.3), D2O/water, and the cosurfactant benzyl alcohol is studied and the bicontinuous phase is identified. Using small angle neutron scattering (SANS) the internal structure of the bicontinuous phase is characterized. In the experiments a temperature range from 261 K to 343 K was covered. The prepared microemulsions were found to exhibit nearly no temperature dependence with respect to their structure and phase behavior. At low temperatures inside the microemulsions water exists in a supercooled liquid state.

Sugar surfactants form very stable microemulsions, which are analyzed by means of small angle neutron scattering. Figure optionsDownload as PowerPoint slideHighlights
► Using sugar surfactants microemulsions are stable over an extreme temperature range.
► Water can be easily supercooled in such a microemuslion.
► SANS reveals that the “renormalized” bending elasticity remains nearly constant between 261 and 343 K.
► The used oil is skin friendly.