Characterization of heterogeneous interaction behaviour in ternary mixtures by dielectric analysis: The H-bonded binary polar mixture in non-polar solvent

The heterogeneous association behaviour of various concentration binary mixtures of mono alkyl ethers of ethylene glycol with ethyl alcohol were investigated by dielectric measurement in benzene solutions over the entire concentration range at 25 degrees C. The values of static dielectric constant eo of the mixtures were measured at 1 MHz using a four terminal dielectric, liquid test fixture and precision LCR meter. The high frequency limiting dielectric constant epsilon(infinity) values were determined by measurement of refractive index n(D) (epsilon(infinity) = n(D)(2)). The measured values of epsilon(o) and epsilon(infinity) were used to evaluate the values of excess dielectric constant epsilon(E), effective Kirkwood correlation factor g(eff) and corrective correlation factor g(f) of the binary polar mixtures to obtain qualitative and quantitative information about the H-bond complex formation. The non-linear behaviour of the observed epsilon(o) values of the polar molecules and their mixtures in benzene solvent confirms the variation in the associated structures with change in polar mixture constituents concentration and also by dilution in non-polar solvents. Appearance of the maximum in epsilon(E) values at different concentration of the polar mixtures suggest the formation of stable adduct complex, which depends on the molecular size of the mono alkyl ethers of ethylene glycol. Further, the observed epsilon(E) < 0 also confirms the heterogeneous H-bond complex formation reduces the effective number of dipoles in these polar binary mixtures. In benzene solutions these polar molecules shows the maximum reduce in effective number of dipoles at 50 percent dilutions. But ethyl alcohol rich binary polar mixtures in benzene solvent show the maximum reduce in effective number of dipoles in benzene rich solutions.