Studies of solubilized micellar solutions. I. Phase studies and particle size analysis of solutions formed with nonionic surfactants

• Published in: Journal of colloid and interface science 1974, Vol.46 (2), p.249-254
• Main Authors: Attwood, D, Currie, L.R.J, Elworthy, P.H
• Format: Article
• Language: English
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/0021-9797(74)90008-3

The preparation and physical properties of oil/water solubilized micellar solutions (so-called “microemulsions”) containing liquid paraffin, glycerol, water and blends of Tween 60 and Span 80 have been examined. Turbidity-spectra methods of particle sizing have shown that an increase of temperature of preparation over the range 25–80°C led to a gradual decrease in the modal diameter and the half-width of the size distribution curve. Phase diagram studies on micellar solutions prepared at 70°C have indicated a pronounced dependence of the area of existence of clear solutions on the ratio of Tween to Span in the system and on the oil content. Light-scattering investigations on these systems have indicated micelle diameters of between 13 and 45 nm. In general, micellar size was increased by increasing the oil content and by decreasing the surfactant/glycerol ratio. No significant effect on micellar diameter was detected as the Tween/Span molar ratio was varied between 1.0 and 1.6.