Lead(II) Di-n-tridecanoate + n-Tridecanoic Acid Phase Diagram:  A Surfactant−Solvent-like Behavior

• Published in: Langmuir Vol. 12; no. 10; pp. 2367 - 2370
• Main Authors: Roux, M. V, Turrión, C, Sánchez Arenas, A, Cheda, J. A. R
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.05.1996
• Subjects: Chemistry; Exact sciences and technology; General and physical chemistry; Liquid-liquid equilibria; Phase equilibria; Surface physical chemistry; Surface-active agents: properties; Polarizing microscope; Differential scanning calorimetry; Phase diagram; Lead Compounds; Enthalpy; Binary system; Composition effect; Experimental study; Soap; Anionic surfactant; Isotropy; Krafft point; Organic salt; Molecular association
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la950655r

The mixture {x(C12H27CO2)2Pb + (1 − x)C12H27CO2H} has been investigated by differential scanning calorimetry and hot-stage polarizing-light microscopy over the whole composition range. Molecular association between the acid and the salt typical of the systems with alkaline cations is not found in the solid state. The complete phase diagram resembles those of the surfactants in water with a Krafft-like effect pointing to the formation of micellar aggregates and lyotropic phases.