title: Microwave dielectric study of an oligomeric electrolyte gelator by time domain reflectometry.
abstract: The dynamics of water molecules in aqueous solutions of an oligomeric electrolyte gelator, poly[pyridinium-1,4-diyliminocarbonyl-1,4-phenylene-methylene chloride] (1-Cl) was characterized by microwave dielectric measurements using the time domain reflectometry method. The dielectric dispersion and absorption curves related to the orientational motion of water molecules were described by the Cole-Cole equation. Discontinuities were observed in the concentration dependence of the dielectric relaxation strength, Deltaepsilonh, as well as in the Cole-Cole parameter, betah. These discontinuities were observed between the samples with concentrations of 6 and 7 g/L 1-Cl/water, which correspond to a change in the transparency. Such a discontinuity corresponds to the observation of the critical concentration of gelation. The interaction between water and 1-Cl molecules was discussed from the tauh-betah diagram. As 1-Cl carries an amide group, it could be expected that 1-Cl may interact hydrophilically with water, but the present result suggests that 1-Cl interact hydrophobically with water.
authors: Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan.
authors: Shyamal Kumar
authors: SK
authors: Kundu
authors: Shin
authors: S
authors: Yagihara
authors: Masaru
authors: M
authors: Yoshida
authors: Mitsuhiro
authors: M
authors: Shibayama
mesh_terms: D017097:Electric Impedance; D004573:Electrolytes / Q000737:chemistry*; D005782:Gels; D008872:Microwaves; D011108:Polymers / Q000737:chemistry*; D013057:Spectrum Analysis; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D004573:Electrolytes; D005782:Gels; D011108:Polymers; D014867:Water