Dielectric relaxation in eugenol

Abstract

The dielectric behaviour of eugenol has been determined over the temperature range 23.5 to –69°C; this range is similar to that used in a previous investigation of the viscoelastic properties. It is found that all the dielectric relaxation data could be reduced to a single curve which could be fitted by a Davidson–Cole equation with the distribution parameter βD= 0.6. Above –56°C, the temperature dependence of the dielectric relaxation time, τD, is the same as that of the viscosity, and differs from that of the viscoelastic retardation time τr. However, the temperature dependence of the resistivity is similiar to that of τr. The results are discussed with regard to the differing aspects of molecular motions which are shown by the dielectric and viscoelastic relaxations.