Abstract
Examination was made of the phase behavior of polyglycerin fatty acid esters in a water-oil system and aggregate structure by phase study and amall angle X-ray scattering (SAXS). Polyglycerin laurate (10G* 0.7L and 20G* 1L) were used, 10G* and 20G* indicating the average polymerization degree of polyglyceryl chain as 10 and 20, respectively. Neither 10G* 0.7L nor 20G* 1L formed a cubic phase in water at 25°C but did so with the addition of a trace amount of decane. The cubic phase was found to be a discontinuous micellar cubic phase (I1) with a face or body centered cubic lattice by SAXS. Micelles in I1 were not completely spherical. The thermal stability of I1 was improved with increase in the solubilization of decane. Maximum solubilization of m-xylene and squalane in I1 was studied and greater solubilization of m-xylene and less solubilization of squalane compared to decane were noted. An excess oil phase was found to coexist with I1 beyond the solubilization limit of I1 and the oil phase could be dispersed in I1 as emulsion droplets. The highly viscous and stable gel emulsion with oil content of 80% could be formulated.
