External Magnetic Field Induced Percolation in Polyvinylidene Fluoride and Nickel Composites

The dielectric properties of polyvinylidene fluoride (PVDF) and nickel (Ni) composites annealed under external magnetic fields were studied here. It was found that a similar percolation effect could be induced by an external longitudinal magnetic field in low filler PVDF/Ni composites. The permittivity of PVDF/Ni (95/5) composites showed a 4 times improvement at low frequency, and the dielectric loss was kept in the range of 0.1-0.4. In comparison to the traditional percolation effect caused by the involvement of conductive particles, field-induced anisotropic percolation may be another type of percolation effect, which can be used to improve the dielectric properties of polymer-based composites.