In situ synthesis of boron nitride “nanonoodles” based epoxy nanocomposites with enhanced thermal and dielectric properties

Abstract The development of low loading fraction nanoscale reinforcements that can be used to improve the dielectric and thermal properties of a polymer remains a challenge by the reason of the insurmountable difficulties with exfoliation and dispersion of polymer nanocomposites. Here, we combined noodle‐like boron nitride nanoribbons (BNNRs) with epoxy resin (EP) by a facile in situ synthesis. The hydroxyl and amino on the BNNRs surface can not only improve dispersibility but also conduct the formation of EP with BNNRs by the in situ ring‐opening reaction. The thermal behavior, dielectric properties, and thermal conductivity of BNNRs/EP nanocomposites with different BNNRs contents were investigated. At an extremely low BNNRs loading fraction of 1 wt%, the thermal conductivity of the nanocomposite increased 48%, which is attributed to the long continuous heat conduction path formed by the strong integration of BNNRs and EP. In addition, the electrical breakdown strength increased from 95.58 to 159.17 kV·mm⁻¹ as the BNNRs content increased, while the nanocomposites maintained acceptable dielectric properties. The results indicate the potential for BNNRs as a new class of nanofiller for dielectric polymers.