Phase diagram of α‐sulfonate methyl esters derived from palm stearin/alcohol/water systems

Abstract

AbstractPhase diagrams of α‐sulfonate methyl ester derived from palm stearin (α‐SMEPS)/alcohol/water systems were mapped at 30±0.1°C. Two main regions—an isotropic and a lamellar liquid crystalline—were the focal points in this system. An increase in alcohol chain length decreased the isotropic region and increased the lamellar liquid crystal region. In the isotropic region, self‐assembly of α‐SMEPS at different alcohol chain lengths was determined by using conductivity and viscosity measurements. The phase boundaries of micelle to bicontinuous structure and bicontinuous structure to inverse micelle transitions in the isotropic regions are proposed from these analytical methods. The increase in alcohol chain length shifted the micelle ⇆ bicontinuous structure to the water‐rich corner, and the bicontinuous structure ⇆ inverse micelle transition moved toward the alcohol‐rich corner.