THE PYROELECTRIC RESPONSE OF POLYMERS AND ITS APPLICATIONS

The pyroelectric effect is the electrical response of a material to a change in temperature. It is found in any polymer containing oriented dipoles. In this review, pyro-electrical experimental techniques are discussed and shown to be reliable, compact and easy to use. The pyro-electric responses of several typical amorphous, semi-crystalline and crystalline polymers are compared. Pyro-electric investigations are useful for the measurement of dipole-relaxation processes in the vicinity of the glass transition in amorphous polymers, for the measurement of relaxation processes and phase transitions in ferro-electric polymers, and for the nondestructive probing of polarization distributions across the polymer-film thickness. In addition, the numerous possible applications of pyroelectric polymers are reviewed and illustrated by an IR sensor for human-body detection and a hydrogen-gas sensor.