Influence of Crystallization on Molecular Dynamics of the Amorphous Phase in Poly(ε-caprolactone) and Poly(ε-caprolactone)/LiClO₄ Complexes Investigated by Dielectric Relaxation Spectroscopy

The dielectric relaxation spectroscopy results indicate that the relaxation peak of PCL for pure PCL and PCL/LiClO₄ complexes shifts to a lower frequency with increasing crystallization temperature, while the amorphous, condensed structure of PCL for pure PCL and PCL/LiClO₄ complexes is slightly affected by crystallization temperature. These findings were obtained from small-angle X-ray scattering (SAXS) measurements. To further understand the effect of crystallization temperature on the relaxation behavior of PCL and PCL/LiClO₄ complexes, the isothermal crystallization process of PCL and PCL/LiClO₄ was probed in situ by dielectric spectra measurement. The analysis indicated that the relaxation dynamics for pure PCL and PCL/LiClO₄ complexes decrease continuously during the isothermal crystallization process, even at the crystallization induction period. This paper presents a detailed discussion of the crystallization mechanisms of the PCL and PCL/LiClO₄ complexes, and the probable explanation as to the effect of crystallization temperature on the relaxation dynamics of PCL and PCL/LiClO₄ .