Abstract
The super-structure control for the piezoelectric polymer, poly(vinylidene fluoride) (PVFE). has been undertaken by many researchers to improve its piezoelectricity. But the preparation methods for the B-phase-rich samples were somewhat complicated. In this investigation, a new preparation method which involves crosslinking of PVF2 is suggested. PVF2 was dissolved in DHF with dicumylperoxide at 15$0^{\circ}C$ for 30min, and then a non-solvent was put into the polymer solution. In this way, PVF2 was crosslinked and crystallized at the same time. Using the simultaneous crosslinking/crystallization method, the PVF2 samples with B and Y characteristics could be produced. When 20% aqueous sulfuric acid solution was used as the non-solvent the pure B-phase PVF2 samples were obtained. When PVF2 was crystallized in the solutions, small amount of crosslinks played a positive role regarding the P-phase content. It is recommended that crystallinity reduction by crosslinks should be avoided to achieve the high piezoelectricity in the PVF2 tramples.
