Piezoelectric, pyroelectric and ferroelectric polymers as a functional soft matter

Among a variety of piezoelectric polymers, PVDF and its copolymer with TrFE exhibit the largest electromechanical coupling coefficient and are, therefore, important for practical applications for soft transducer elements. They also exhibit pyroelectric activities and are, more importantly, ferroelectric polymers undergoing ultrafast polarization switching. The p-PP electret containing oblate ellipsoidal air void is another important piezoelectric polymer characterized by extreme softness. The typical values of their electromechanical properties are summarized in Table I.