Correlation between pyroelectric properties and dielectric behaviour in ferroelectric polymers

The piezoelectric and pyroelectric properties of ferroelectric polymers are strongly influenced by temperature. This work presents a comparative study of pyroelectric properties of PVDF and Polyamide 11. Both temperature dependence and thermal stability of the pyroelectric coefficient is discussed in relation with the analysis of transitions and dielectric relaxations. Experimental results show the higher thermal stability of pyroelectric properties of Polyamide 11 in comparison to PVDF, although the value of pyroelectric coefficient of as-poled samples is greater in PVDF. The pyroelectric coefficient shows distinct temperature dependence below and above thermal transitions and especially the glass transition.