Reduced polyaniline decorated reduced graphene oxide/polyimide nanocomposite films with enhanced dielectric properties and thermostability

This study reports the synthesis and characterization of reduced polyaniline decorated reduced graphene oxide/polyimide (RGO@R-PANI/PI) nanocomposite films with enhanced dielectric properties and thermostability. The steric effects of R-PANI decorated on the surface of RGO not only prevented the aggregation of RGO but also improved the dispersion of RGO@R-PANI nanosheets in the PI matrix, leading to higher dielectric constant (ε) and lower dielectric loss (tanδ) of the RGO@R-PANI/PI nanocomposite films than those of the RGO/PI nanocomposite films. The highest dielectric constant (25.84) was observed in the 20 wt% RGO@R-PANI/PI nanocomposite film (the mass fractions of RGO was 3.44%) with a low dielectric loss of 0.11 at 1 kHz. Furthermore, the 5 wt% weight loss temperature of the 20 wt% RGO@R-PANI/PI nanocomposite films was 480 °C, indicating the nanocomposite films are good candidates for dielectric materials under extreme temperature.