COMPARING THE TIME-INVARIANT AND TIME-VARIANT DIELECTRIC-RELAXATION DATA SIMULATED FOR A MACROMOLECULES GROWTH

The reliability of information obtained from dielectric data on the ti me-variant relaxation behaviour of a material has been examined. To do this, we first simulated the dielectric permittivity and loss data as a function of ac frequency for a series of time-invariant systems, wh ich contained contributions from interfacial impedance, de conductivit y and dipolar relaxation, assuming that the static and high-frequency permittivities, the de conductivity and the characteristic relaxation time change with time in a way that qualitatively agreed with those de termined from experiments. These data were then transformed into sets of fixed frequency dielectric data as a function of time, and then ana lyzed pretending that the original parameter; were unknown to us. The analysis gave parameters in reasonable agreement with those used for t he simulation of the data. Thus, fixed frequency dielectric measuremen ts on a time-variant system may be relied upon to yield information on the time-invariant states of the system, although, ideally speaking, measurement of time-invariant states would be desirable if errors aris ing from the interpolation needed to obtain the data for a time-invari ant state could be eliminated.