Dielectric Relaxation of Methyl Methacrylate and Ethyl Methacrylate on Complexation with Phenols

Dielectric absorption studies of H-bonded complexes of methyl methacrylate (MMA) and ethyl methacrylate (EMA) with p-cresol, p-chlorophenol, 2,4-dichlorophenol, and p-bromophenol were studied at microwave frequency of 9.37 GHz in dilute solution of carbon tetrachloride at 308 K. Different dielectric parameters like dielectric constant ɛ, dielectric loss ɛ at microwave frequency, static dielectric constant ε0 and dielectric constant ε∞ at optical frequency were determined. The validity of the single frequency equation of Higasi et al. for multiple relaxation time τ(1) was found to be a function of the hydrogen bonding strength of phenolic hydrogen, whereas the group rotation relaxation time τ(2) was a function of the steric interaction of proton donor. The relaxation time was the maximum at 50:50 (molar ratio) of methacrylates with phenols.