Dielectric Spectroscopy of Plasma-Treated Polyimide Films in the Presence of Boron Nitride

Aromatic polyimide films were treated by pulsed electrical discharges formed in water containing different quantities of hexagonal boron nitride (h-BN). The relative permittivity was measured across wide ranges of frequencies and temperatures by broadband dielectric spectroscopy. Slightly increased values of the dielectric constant for the samples treated in water containing 10 mg and 20 mg of h-BN were observed. The sample treated by pulsed electrical discharge in water containing 30 mg of h-BN remained unchanged. The electrical conductivity decreased with increasing BN concentration. The plasma treatment affected the dielectric behavior of the films without causing major modifications to the polymer structure.