Phase equilibria in high energy density PVDF-based polymers.
The phase diagrams of polyvinylidene fluoride (PVDF) and its copolymers with chlorotrifluoroethylene (CTFE) are investigated by first-principles calculations. Both PVDF and dilute P(VDF-CTFE) prefer nonpolar structures at zero field, but transform to a polar phase below the breakdown field. The critical field decreases with increasing CTFE content, facilitating the transformation. In disordered P(VDF-CTFE), a distribution of concentrations leads to a range of polar transitions, resulting in ultrahigh energy density. These results explain well experimental observations of very high-energy density in P(VDF-CTFE).
Center for High Performance Simulation and Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-7518, USA.
V
V
Ranjan
L
L
Yu
Marco Buongiorno
MB
Nardelli
J
J
Bernholc
D011108:Polymers / Q000737:chemistry
D011108:Polymers