Phase Transitions of Poly(vinylidene Fluoride) under Coupled Electric-Strain Field

Poly(vinylidene fluoride) (PVDF) is a pivotal piezoelectric polymeric building block for advanced electronics, whose piezoelectric property is determined by the proportion of the polar β phase. Based on molecular dynamics simulations, this work assessed the phase transition behaviors of PVDF from the α phase to the β phase under a coupled electric-strain field. It is found that the presence of strain can significantly reduce the threshold strength of the electric field, which triggers robust and stable phase transitions. Similarly, the presence of an electric field will reduce the required stress or strain that initiates phase transitions. The findings obtained in this work could provide useful guidelines for manipulating PVDF with the required piezoelectric properties.