Diamond matter-enabled low-leakage conductance to achieve the balanced dielectric properties of PVDF/ZrC/diamond blend films

For high dielectric constant, conductive carbide ceramic fillers are scattered in polymer to fabricate composites. However, high conductivity of carbides will lead to high leakage conductance and dielectric loss. In this work, to balance dielectric properties, polymer/ZrC/diamond blends were prepared via complementation of fillers. To perform property comparison, polymer/ZrC blends were prepared. Crystal forms and micromorphology of fillers were confirmed. All blends were measured to obtain dielectric constant, dielectric loss and conductivity at various frequencies. Compared to polymer/ZrC blends, dielectric constant of ternary blends slightly decreases and dielectric loss sharply reduces. By analysing ternary blends, strong interaction at polymer/ZrC interface results in high dielectric constant and insulating diamond results in low-dielectric loss via greatly-decreased leakage conductance. Partner employment of ZrC and diamond is distinctive. Ternary blend loaded with 5 wt% ZrC and 3 wt% diamond exhibits well-balanced dielectric performances (dielectric constant ~ 35.3; dielectric loss ~ 0.48) at 100 Hz. This work will provide valid route for balancing dielectric properties of polymer/conductive carbide blends.