Pyroelectricity in polymers

The piezo- and the pyroelectric properties of poled polyvinylidene fluoride (PVDF) and its copolymers arise primarily from the ferroelectric orientation of the C-F dipoles rather than trapped space charges. Composite films, consisting of ceramic powder, introduced in PVDF matrix, combine the mechanical strength of polymeric films with high piezo- and pyroelectric responses of the ceramics. Present paper provides a brief review of the nature and origin of pyroelectricity in (i) PVDF, (ii) its copolymer vinylidene fluroide-trifluoroethylene (BDF-TrFE) and (iii) their composites (polymer-ceramic).