Piezoelectricity in Helical Polymer Chains

Abstract

Piezoelectric effect has been observed by a number of investigators in the uniaxially orientated helical polymers, in which the piezoelectric polarization appears perpendicular to the shearing plane. To explain this, the piezoelectric polarization is theoretically treated for a distorted helical polymer chain with effective charges or dipole moments on the main chain. The piezoelectric effect occur only in an optical shear mode of lattice vibration along the helical axis. As examples, the piezoelectric polarization is calculated in polyoxymethylene-type helical chain and quasi-polypeptide-type one.