Preparation and Energy Storage Characteristics of Novel Poly(M-phenylene Isophthalamide) Dielectric Composites

Novel polymer-based dielectric composites were prepared by adding core-double-shell structured PDA@TiO2@BaTiO3 nanoparticles (PTBP) into Poly(m-phenyleneisophthalamide) (PMIA). In order to suppress the local electric field distortion caused by different dielectric constants and improve the interfacial compatibility between BaTiO3 (BT) and PMIA, TiO2 and polydopamine (PDA) were wrapped on BT to fabricate core-double-shell structured PTBP nanoparticles. The obtained results indicate the dielectric constant of PTBP/PMIA dielectric composite obviously increases with increment of PTBP content. When PTBP content reaches up to 10 wt%, the dielectric constant of PTBP/PMIA composite dielectric increases by 57.1% compared with that of as-prepared PMIA at 103 Hz. The dielectric properties of PTBP/PMIA dielectric composites also maintain stable at high temperature (>150 ℃), which is suitable for applications in high-temperature conditions. In addition, PTBP particles significantly improve the energy storage properties of PTBP/PMIA dielectric composites. When the PTBP content is 10 wt%, the maximum values of energy storage density (Ue) and discharge energy density (Ud) are 1.91 J/cm3 and 1.23 J/cm3 at room temperature, respectively, which are 103.2% and 61.8% higher than that of as-prepared PMIA. Consequently, this research provides a new approach to fabricate novel high-temperature polymer-based dielectric composites.