Influence of the fine structure of glass forming materials on the overlapping of the alpha and secondary relaxations

The dielectric behavior of a set of poly benzyl methacrylates with methyl, fluorine, chlorine and difluorine substitutes in the phenyl ring is reported. Attention is paid to the deconvolution of overlapping processes with the aim of obtaining a deeper insight into the influence of the fine chemical structure on the splitting of the α and β relaxations. Deconvolutions are carried out on the retardation time spectra calculated from the dielectric loss in the frequency domain using the linear regularization method. Some difficulties associated with the detection of the β relaxation of this set of polymers were resolved by means of the thermostimulated depolarization currents experiments. © 2007 Elsevier B.V. All rights reserved.