화학공학소재연구정보센터
Journal of Physical Chemistry B, Vol.113, No.30, 10112-10116, 2009
Microwave Dielectric Study of an Oligomeric Electrolyte Gelator by Time Domain Reflectometry
The dynamics of water molecules in aqueous solutions of an oligomeric electrolyte gelator, poly(pyridinium-1,4-diyliminocarbonyl-1,4-phenylene-methylene chloride] (1-CI) 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, Delta epsilon(h), as well as in the Cole-Cole parameter, beta(h). 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 tau(h)-beta(h) 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.