Effect of alkyl chain asymmetry on catanionic mixtures of hydrogenated and fluorinated surfactants.
In this work we studied and compared the physicochemical properties of the catanionic mixtures cetyltrimethyl-ammonium bromide-sodium dodecanoate, cetyltrimethyl-ammonium bromide-sodium perfluorodacanoate, octyltrimethylammonium bromide-sodium perfluorodacanoate and cetyltrimethyl-ammonium bromide-sodium octanoate by a combination of rheological, transmission electron microscopy (TEM) and polarized optical microscopy measurements. The binary mixtures of the surfactants have been analyzed at different mixed ratios and total concentration of the mixture. Mixtures containing a perfluorinated surfactant are able to form lamellar liquid crystals and stable spontaneous vesicles. Meanwhile, system containing just hydrogenated surfactants form hexagonal phases or they are arranged in elongated aggregates.
Soft Matter and Molecular Biophysics Group, Department of Applied Physics, University of Santiago de Compostela, E-15782, Spain.
Elena
E
Blanco
Carlos
C
Rodriguez-Abreu
Pablo
P
Schulz
Juan M
JM
Ruso
D000465:Algorithms; D000838:Anions / Q000737:chemistry; D002210:Caprylates / Q000737:chemistry; D002414:Cations, Monovalent / Q000737:chemistry; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D055598:Chemical Phenomena; D003652:Decanoic Acids / Q000737:chemistry; D005466:Fluorocarbons / Q000737:chemistry; D007850:Lauric Acids / Q000737:chemistry; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D008859:Microscopy, Polarization; D010316:Particle Size; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012212:Rheology; D013501:Surface-Active Agents / Q000737:chemistry*; D055682:Viscoelastic Substances / Q000737:chemistry; D014783:Viscosity
D000838:Anions; D002210:Caprylates; D002414:Cations, Monovalent; D002593:Cetrimonium Compounds; D003652:Decanoic Acids; D005466:Fluorocarbons; D007850:Lauric Acids; D008823:Micelles; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents; D055682:Viscoelastic Substances; C030358:lauric acid; C042006:octyltrimethylammonium; C036567:perfluorodecanoic acid; C023036:perfluorooctanoic acid; C031492:octanoic acid; D000077286:Cetrimonium