Dielectric processes in heavy oils — III. Evidence for cooperative behavior among polar species

Dielectric spectroscopy was used as a technique for charting the course of the nature and/or number density of polar molecules resulting from physical or chemical changes in heavy hydrocarbon fluids. This effort was based on the use of an oscillating electric field to impose a time-varying macroscopic polarization on a system by attempting to force the alignment of the permanent dipoles associated with the molecules under investigation. The real part of the dielectric permittivity ε' is proportional to the nature (i.e., physical size) and number density of the permanent dipoles responding in the system. Theoretical and experimental aspects of the technique are well understood in the case of simple molecules (1).