The use of the Wagner function to describe poled-order relaxation processes in electrooptic polymers

The Wagner (lognormal) time decay function is used to describe decay of the second harmonic signal due to electric field poled-order relaxation in the guest—host polymer system 20 wt% lophine 1 in Ultem®. This function can be related to a Gaussian distribution of Arrhenius activation energies. From the temperature dependence of the relaxation process one can determine the average value for the activation energy. In the present case a value of 40 kcal/mol is found consistent with experimental values obtained for a variety of other thermally activated processes in polymers.