Novel Polyarylene Ether Nitrile/BaTiO3-Decorated WS2 Nanohybrid Crosslinked Nanocomposites for Thermal-Stable Dielectrics

To prepare high-temperature-resistant dielectric composite films, a novel three-dimensional nanofiller was fabricated using carboxylated polyarylene ether nitrile as a bridge, which tightly loads BaTiO3nanoparticles onto WS2nanosheets (WS2@BT) via in situ chemical bonding. Afterward, the WS2@BT nanofiller was introduced into the polyarylene ether nitrile (PEN) matrix, and high-temperature heat treatment was performed to form a crosslinked network, yielding CPEN/WS2@BT nanocomposites. Notably, the modified WS2@BT effectively improves the compatibility between the nanoparticles and the PEN matrix, which is superior to the compatibility of unmodified nanofillers with the matrix. Moreover, after crosslinking, CPEN/WS2@BT exhibits excellent comprehensive performance: when the filler content is 30 wt%, its glass transition temperature (Tg) reaches 257.83 °C, significantly higher than that of PEN/WS2@BT, and its dielectric constant is 193% higher than that of pure CPEN. In addition, the dielectric temperature coefficient remains below 1 × 10−3°C−1in the range of 25–220 °C. Overall, this work provides an effective and reliable strategy for preparing high-performance, high-temperature-resistant composite dielectric films.