Thermally stimulated depolarization currents : Study of β-relaxations of amorphous polyesters

The β-relaxation of amorphous polyesters was studied by measurement of Thermally Stimulated Depolarisation Currents in order to elucidate the nature of the motions at the origin of the β-relaxation. The β-relaxation peaks differ for the studied polymers. The first component, β 1 can be assigned to the motion of carboxyl groups while the second component, β 2 must be attributed to motion along the chain of a short segment. By the use of elementary spectra it appears that the motions which occur during the β relaxation are localized and non-cooperative.