Dielectric relaxation studies in some phenolic mannich bases

The dielectric permittivity (ε′) and loss factor (ε″) of six phenolic Mannich bases are reported at cm and mm wavelengths in the temperature range 30-70°C. The analysis of dielectric data in terms of Cole-Cole arc and multiple relaxation times reveal that the overall molecular rotation appears to be the predominant relaxation mechanism in these substituted phenols. The activation parameters have been calculated assuming dielectric relaxation to be a rate process.