title: Synthesis of a new zwitterionic surfactant containing an imidazolium ring. Evaluating the chameleon-like behavior of zwitterionic micelles.
abstract: Synthesis of a new zwitterionic surfactant containing the imidazolium ring 3-(1-tetradecyl-3-imidazolio)propanesulfonate (ImS3-14) is described. The solubility of ImS3-14 is very low but increases on addition of a salt which helps to stabilize the micellized surfactant. Fluorescence quenching and electrophoretic evidence for ImS3-14 shows that the micellar aggregation number is only slightly sensitive to added salts, as is the critical micelle concentration, but NaClO(4) markedly increases zeta potentials of ImS3-14 in a similar way as in N-tetradecyl-N,N-dimethylammonio-1-propanesulfonate (SB3-14) micelles. The rate of specific hydrogen ion catalyzed hydrolysis of 2-(p-heptoxyphenyl)-1,3-dioxolane and equilibrium protonation of 1-hydroxy-2-naphthoate ion in zwitterionic micelles of ImS3-14 and SB3-14 are increased markedly by NaClO(4) which induces anionoid character and uptake of H(3)O(+), but NaCl is much less effective in this respect. Comparison of ImS3-14 with SB3-14 is based on experimental evidence, and computational calculations indicate similarities and differences in structures of both compounds.
authors.affiliation: Departamento de Química, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina 88040-900, Brazil.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Tondo
authors.forename: Elder C
authors.initials: EC
authors.lastname: Leopoldino
authors.forename: Bruno S
authors.initials: BS
authors.lastname: Souza
authors.forename: Gustavo A
authors.initials: GA
authors.lastname: Micke
authors.forename: Ana C O
authors.initials: AC
authors.lastname: Costa
authors.forename: Haidi D
authors.initials: HD
authors.lastname: Fiedler
authors.forename: Clifford A
authors.initials: CA
authors.lastname: Bunton
authors.forename: Faruk
authors.initials: F
authors.lastname: Nome