STRUCTURE OF A TRIGLYCERIDE MICROEMULSION - A SMALL-ANGLE NEUTRON-SCATTERING STUDY

The microscopic structure of a microemulsion of soybean oil, water-eth anol (80/20 wt %), and polyoxyethylene(40) sorbitol hexaoleats has bee n studied with small angle neutron scattering. The concentrations of t he three components are varied such that the oil-surfactant ratio is c onstant and stable microemulsions are obtained in regions of the phase diagram corresponding to bicontinuous and L2 phases. Small angle neut ron scattering is measured as a function of concentration and temperat ure in order to describe the structure of the microemulsions. The resu lts are consistent with a bicontinuous phase in the cases of largest a queous content. In the low aqueous concentration samples, a substantia l correlation is found in the spatial distribution of this minority ph ase.