[Micellar formation and micellar structure of poly(oxyethylene)-hydrogenated castor oil]

The effects of the oxyethylene chain length of poly(oxyethylene) hydrogenated castor oil (HCOn) on the micellar formation and on the micellar structure were investigated. Some physicochemical properties of HCOn (critical micelle concentration cmc, surface tension at cmc, free energy of micellization, and surface excess) concerning surface-activity were measured. These physicochemical properties were little affected by the oxyethylene chain length of HCOn. In addition, several physical techniques have been used to study the micellar structure of HCOn. It was found that HCOn micelles were spherical or nearly spherical, and that an increase in the oxyethylene chain length led to an increase in the looseness of HCOn micelle.