Structure-interfacial properties relationship and quantification of the amphiphilicity of well-defined ionic and non-ionic surfactants using the PIT-slope method.
The Phase Inversion Temperature of a reference C10E4/n-Octane/Water system exhibits a quasi-linear variation versus the mole fraction of a second surfactant S2 added in the mixture. This variation was recently proposed as a classification tool to quantify the Hydrophilic-Lipophilic Balance (HLB) of commercial surfactants. The feasibility of the so-called PIT-slope method for a wide range of well-defined non-ionic and ionic surfactants is investigated. The comparison of various surfactants having the same dodecyl chain tail allows to rank the polar head hydrophilicity as: SO3Na⩾SO4Na⩾NMe3Br>E2SO3Na≈CO2Na⩾E1SO3Na⩾PhSO3Na>Isosorbide(exo)SO4Na≫IsosorbideendoSO4Na≫E8⩾NMe2O>E7>E6⩾Glucosyl>E5⩾Diglyceryl⩾E4>E3>E2≈Isosorbide(exo)>Glyceryl>Isosorbide(endo). The influence on the surfactant HLB of other structural parameters, i.e. hydrophobic chain length, unsaturation, replacement of Na(+) by K(+) counterion, and isomerism is also investigated. Finally, the method is successfully used to predict the optimal formulation of a new bio-based surfactant, 1-O-dodecyldiglycerol, when performing an oil scan at 25 °C.
Université de Lille 1 and ENSCL, Unité de Catalyse et de Chimie du Solide, CNRS UMR 8181, Equipe CISCO, Cité Scientifique, F-59655 Villeneuve d'Ascq, France; Laboratorio FIRP, Ingeniería Química, Universidad de Los Andes, Mérida 5101, Venezuela.
Jesús F
JF
Ontiveros
Université de Lille 1 and ENSCL, Unité de Catalyse et de Chimie du Solide, CNRS UMR 8181, Equipe CISCO, Cité Scientifique, F-59655 Villeneuve d'Ascq, France.
Christel
C
Pierlot
Université de Lille 1 and ENSCL, Unité de Catalyse et de Chimie du Solide, CNRS UMR 8181, Equipe CISCO, Cité Scientifique, F-59655 Villeneuve d'Ascq, France.
Marianne
M
Catté
Université de Lille 1 and ENSCL, Unité de Catalyse et de Chimie du Solide, CNRS UMR 8181, Equipe CISCO, Cité Scientifique, F-59655 Villeneuve d'Ascq, France.
Valérie
V
Molinier
Laboratorio FIRP, Ingeniería Química, Universidad de Los Andes, Mérida 5101, Venezuela.
Jean-Louis
JL
Salager
Université de Lille 1 and ENSCL, Unité de Catalyse et de Chimie du Solide, CNRS UMR 8181, Equipe CISCO, Cité Scientifique, F-59655 Villeneuve d'Ascq, France. Electronic address: Jean-Marie.Aubry@univ-lille1.fr.
Jean-Marie
JM
Aubry
Hydrophilic Lipophilic Balance; Optimal formulation; Phase Inversion Temperature; Surfactant classification