Communication—Tunable Lorentz-Type Negative Permittivity of PANI/Epoxy Resin Composites in the Frequency Range from 3 kHz to 1 MHz

Negative permittivity in percolation composites garnered significant interest due to its promising implications for practical applications. This study demonstrates that the percolation threshold of the polyaniline(PANI)/epoxy resin composite falls within the range of 40 wt% to 50 wt%. Beyond this percolation threshold, the composites exhibit a corresponding negative dielectric behavior. Notably, at a high PANI content level of 90 wt%, the permittivity exhibits characteristics akin to Lorentz resonance type behavior. This research presents an effective approach to exhibit tunable low-frequency negative permittivity through Lorentz resonance.