Fatty Soil Removal in Ionic Microemulsion Systems

The microstructure of the one-phase region in quarternary system of sodium oleate/ water / monobutyl poly (oxyalkylene) ether/hydrocarbon was examined by electrical conductivity, viscocity and pulsed field gradient spin-echo (PGSE) NMR measurements. Structural transition from the water-continuous to bicontinuous and oil-continuous microemulsion was detected based on water content in this system. Soil removal was studied to determine the effects of microemulsion structures, using glycerol trioleate, lanolin and abietic acid as model soils. Rolling-up was occurred only in a bicontinuous microemulsion, indicating low interfacial tension of the bicontinuous structure to possibly facilitate the penetration of surfactant and monobutyl poly (oxyalkylene) ether molecules into the soil, followed by rolling-up.