Enhanced thermal conductivity of epoxy composites using boron nitride nanoplatelets prepared by Fe3O4 assisted liquid-phase exfoliation

Abstract

Liquid-phase exfoliation was employed to fabricate BN nanoplatelets (BNNPs) with the assistance of an additional shear force from Fe3O4 nanoparticles. Iron-oxide nanoparticles vibrated between BN layers and bulk BN particles were exfoliated into nanoplatelets. A thermally conductive composite was fabricated by the incorporation of the resultant BNNP into an epoxy matrix. After exfoliation, BNNP exhibited better dispersion in the polymer composite compared to bulk BN due to the reduced mean interparticle distances. Thus, the introduction of BNNP enables the decrease in the thermal percolation threshold via the formation of heat flow paths and enhancement of the thermal conductivity by 480% with the addition of a filler content of 30 wt%. © 2019 Elsevier Ltd and Techna Group S.r.l.