Microwave absorption and relaxation processes of ternary mixtures of non-rigid polar liquids

707-713The dielectric absorption of three acrylates and their mixture compositions as liquid dielectric samples have been studied at MW frequency 9.132 GHz in dilute solution of carbon tetrachloride in the temperature range 300-330 K. Different dielectric parameters like dielectric constant ɛ′ and dielectric loss ɛ′′ at microwave frequency, dielectric constant ɛδ at static frequency and dielectric constant ɛ∞ at optical frequency have been determined. Using these dielectric data, distribution parameter α, various relaxation times, viz. <img src='/image/ spc_char/tow.gif' border=0>0, <img src='/image/ spc_char/tow.gif' border=0>1, and <img src='/image/ spc_char/tow.gif' border=0>2 of individual components and their ternary mixture compositions have been calculated. Thermo dynamical parameters like molar energy of activation ΔFɛ molar enthalpy of activation ΔHɛ and molar entropy of activation ΔSɛ have been evaluated by considering the relaxation as the rate process. Variation of In (<img src='/image/ spc_char/tow.gif' border=0>2T) versus 1/T indicates exponential decay of relaxation time with temperature for dielectric relaxation process. The relaxation time values for single component solutions agree well with literature values while relaxation times of ternary mixture compositions are consistent with the computed values obtained from various theoretical relations

Dielectric relaxation in ternary mixtures of benzotrifluorides

430-435Dielectric relaxation in four ternary systems of benzotrifluorides consisting of benzotrifluoride, 2-chloro-benzotrifluoride and 2-amino-benzotrifluoride has been studied at 9.408 GHz over a temperature range 290-330 K. Static dielectric constant and refractive index of individual components of these benzotrifluorides and their mixture compositions have been measured. The measured dielectric data of these benzotrifluorides have been discussed in terms of distribution of relaxation time and its variation with temperature. The process of dipole orientation and viscous flow in these liquids has been discussed on the basis of rate theory. Various thermodynamical parameters viz. entropy,enthalpy and free energy of activation have been determined using measured dielectric data. These calculated thermo dynamical parameters for relaxation processes and viscous flow processes confirm existence of both inter-molecular and intra-molecular orientations in these substituted benzotrifluorides. These polar compounds under investigation have been used in pure form as dielectric samples. The methods used to obtain results presented in this paper are based on the measurement of standing wave pattern in a dielectric medium.</span