Monitoring the cold crystallization of poly(3-hydroxy butyrate) via dielectric spectroscopy

Dielectric spectroscopy has been used to monitor the cold crystallization kinetics of poly(3-hydroxy butyrate), PHB, just above the glass transition temperature of the amorphous chains. Although the polymer shows a relatively complex dielectric scenario, an easy and fast analysis of the crystallization kinetics was performed by choosing an appropriate temperature range in which the structural relaxation is the only process present in the spectra of the amorphous samples. It was possible to monitor in real time the crystallization kinetics by analysing the changes in the intensity of the α-relaxation process. A recently proposed methodology to overcome some systematic deviation of the Avrami approach, was applied to treat the experimental data.