Barium titanate nanowires (BTN) with high aspect ratio were synthesized through a hydrothermal method by using titanium dioxide (TiO2) nanoparticles. In order to improve the compatibility between BTN and polymer matrix as well as maintain the completely chemical structure of BTN, Polyvinylpyrrolidone (PVP) was selected as modification that was wrapped on the surface of BTN by physical adsorption and the modified BTN nanowires were named as P-BTN. Subsequently, P-BTN were added into poly(metaphenylene isophthalamide) (PMIA) matrix to prepare PMIA dielectric composite. The dielectric property and breakdown strength of P-BTN/PMIA composite were investigated by varying the content of P-BTN nanoparticles; furthermore, effect of high temperature on dielectric properties of P-BTN/PMIA composites was also researched. The obtained consequences indicate that, due to effective modification of PVP on BTN, the prepared P-BTN are homogeneously dispersed in PMIA matrix even at relatively high P-BTN content, and the compatibility between BTN and PMIA matrix improves as well. With increasing content of P-BTN, the dielectric constant of P-BTN/PMIA composites obviously increases. For example, the dielectric constant of PMIA composite with 15wt% P-BTN increases to 18.5, which is 7.4 times that of pure PMIA, and the dielectric loss keeps at low value. It is worth noting that, even at high temperature (150-250℃), the dielectric properties of prepared P-BTN/PMIA composites are still stable, which can meet the requirements of high temperature for dielectric composites. In addition, the breakdown strength of PMIA composite can be enhanced at low content of P-BTN nanoparticles, which is suitable for application under highly electric field. © 2022, Materials Review Magazine. All right reserved.
