Dielectric relaxation studies of aqueous solution of polyethylene glycol 200 (PEG200), using time-domain reflectometry

Using time-domain reflectometry measurement technique, the dielectric complex permittivity spectra over the frequency range 10MHz to 30GHz have been studied for series of various compositions, at various temperatures, for the aqueous solution of polyethylene glycol 200 (PEG200). The relaxation in these mixtures can be described by a single relaxation time using the Cole-Cole model.[1] The values of static dielectric constant, dielectric relaxation time, excess dielectric permittivity, Bruggeman factor and Kirkwood correlation factor are determined for the series of various compositions. Using above parameters, intermolecular interaction of molecules at molecular level are predicated. The negative values of excess dielectric permittivity suggest reduction in dipole moment, and the values of Kirkwood correlation factor, which are found to be greater than unity, show the parallel orientation of electric dipoles. The study confirms that the intermolecular homogeneous and heterogeneous hydrogen bonding varies significantly with the increase in the concentration of PEG200 in water.