Structure of the microemulsion of polyglycerol polyricinoleate encapsulating vitamin E

Abstract

The structures of micelles and microemulsions consisting of polyglycerol polyricinoleate (PGPR) were investigated by small-angle X-ray scattering (SAXS) and rheological measurements. The SAXS results show that amphiphilic PGPR molecules form stable micelles in glycerol. When vitamin E is added to the PGPR micelles, it is encapsulated in the micelles and forms an emulsion. These micelles are stable towards mechanical shearing up to a shear rate of 1000 s–1, with shear thinning occurring in the emulsion above 100 s–1, indicating that the emulsion may undergo break up by shearing, but recovers the structure by releasing shear strain.