Relation between pre-exponential factor and activation energy in dark conductivity of polyethylene

The conductivities of polyethylene obtained by different authors have been scattered over many orders of magnitude, and their activation energies have also varied from about 0.4 to 1.7 eV. To deduce a general rule for the data, using the available data so far published, the plot of the logarithm of the pre-exponential factor against the activation energy was made. As a result, the compensation rule was found to hold approximately for the conductivity of polyethylene at low electric fields.