title: Synthesis and Monolayer Behaviors of Succinic Acid-Type Gemini Surfactants Containing Semifluoroalkyl Groups.
abstract: In this work, novel succinic acid-type gemini surfactants containing semifluoroalkyl groups, dl- and meso-2,3-bis[Rf-(CH2)n]-succinic acids (Rf = C4F9, C6F13, C8F17; n = 2, 9), were successfully synthesized, and the effects of Rf, methylene chain length (n), and stereochemistry on their monolayer behaviors were studied. Critical micelle concentrations (CMC) of dl- and meso-2,3-bis[C4F9(CH2)9]-succinic acids were one order of magnitude smaller than that of the corresponding 1+1 type surfactant, C4F9(CH2)9COOH. From surface pressure-area (π-A) measurements, the lift-off areas of the geminis were found to decrease in the order C4F9 ≥ C6F13 > C8F17, regardless of methylene chain length and stereochemistry. The zero-pressure molecular areas of the geminis were twice those of the corresponding 1+1 type surfactants. Based on Gibbs compression modulus analysis, it was clarified that 2,3-bis[C8F17(CH2)n]-succinic gemini with short methylene chains (n = 2) would form more rigid monolayers than those having long methylene chains (n = 9). Unlike for 2,3-bis(alkyl)-succinic acids, the effects of stereochemistry on the monolayer behavior of semifluoroalkylated geminis were small.
authors.affiliation: Department of Chemistry and Materials Technology, Kyoto Institute of Technology.
authors.forename: Tokuzo
authors.initials: T
authors.lastname: Kawase
authors.forename: Youhei
authors.initials: Y
authors.lastname: Nagase
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Oida
mesh_terms: D002117:Calcitriol / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D008823:Micelles; D013237:Stereoisomerism; D013386:Succinates / Q000138:chemical synthesis / Q000737:chemistry*; D013500:Surface Tension; D013501:Surface-Active Agents / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: C411462:1,25-dihydroxy-21-(3-hydroxy-3-methylbutyl)vitamin D(3); D008823:Micelles; D013386:Succinates; D013501:Surface-Active Agents; D002117:Calcitriol