title: Self-assembly of double-tail anionic surfactant having cyanobiphenyl terminal groups in water.
abstract: This study reports the interfacial properties and lyotropic liquid crystal formation of sodium 1,2-bis{6-[4-(4-cyanophenyl)phenyloxy]hexyloxycarbonyl}ethanesulfonate (SBCPHS), which is a double-tail surfactant with cyanobiphenyl terminal groups, in water. Polarized microscopic observation of water/SBCPHS mixtures revealed the presence of columnar and lamellar phases. In the lamellar phase, myelin figures representing multilamellar tubes were observed, and some of these figures had a double-helix structure. In order to examine these liquid crystal structures in detail, the bilayer thickness of the lamellar tubes and the lattice parameters of the columnar phase were measured by small-angle X-ray scattering analysis. Four scattering peaks that could be ascribed to C2/m symmetry were observed for the columnar phase. The bilayer thickness and one of the lattice parameters were smaller than twice the molecular length of SBCPHS; this showed that the liquid crystal phases had intercalated structures. Comparison of SBCPHS with a typical double-tail hydrocarbon surfactant revealed that the cyanobiphenyl terminal groups in the former helped increase the stability of the liquid crystal formed at low temperatures. The stabilizing effect of the cyanobiphenyl terminal groups on the liquid crystals could have been driven by electrostatic intermolecular interactions between the terminal groups in antiparallel arrangement of the SBCPHS molecules.
authors.affiliation: Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan. sagisaka@cc.hirosaki-u.ac.jp
authors.forename: Masanobu
authors.initials: M
authors.lastname: Sagisaka
authors.forename: Masaya
authors.initials: M
authors.lastname: Hino
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nakanishi
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Inui
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: Koji
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Hideki
authors.initials: H
authors.lastname: Sakai
authors.forename: Masahiko
authors.initials: M
authors.lastname: Abe
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yoshizawa
mesh_terms: D000327:Adsorption; D001713:Biphenyl Compounds / Q000737:chemistry; D003460:Crystallization; D005614:Freeze Fracturing; D006838:Hydrocarbons / Q000737:chemistry; D046529:Microscopy, Electron, Transmission / Q000379:methods; D008956:Models, Chemical; D015394:Molecular Structure; D012542:Scattering, Radiation; D013499:Surface Properties; D013500:Surface Tension; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature; D014867:Water / Q000737:chemistry*; D014965:X-Rays
chemical_list: D001713:Biphenyl Compounds; D006838:Hydrocarbons; D013501:Surface-Active Agents; D014867:Water