Dielectric spectroscopy of poly(butylene succinate) films

Dielectric properties of poly(butylene succinate) crystallized under different conditions have been reported in the temperature range of 163-383 K and in the frequency range of 0.01-10⁵ Hz. Both the dipolar α and β processes have been identified at low temperatures: the α process is associated with the amorphous fraction while the β with the relaxations in both the amorphous and crystalline fractions. The space charge effect dominates the high temperature dielectric spectra. These spectra have been analyzed in the light of an equivalent circuit model. The Maxwell-Wagner-Sillars polarization, electrode polarization and free charge motion are well resolved. At 383 K, near the melting temperature (387 K), massive melting and subsequent recrystallization have been observed. The peculiar evolution of the spectra is also analyzed using the same equivalent circuit model. The relationship between the fitting parameters and the evolved microstructures is discussed.