Enhanced Thermal Conductivity and Balanced Mechanical Performance of PP/BN Composites with 1 vol% Finely Dispersed MWCNTs Assisted by OBC

Abstract 1 vol% multiwalled carbon nanotubes (MWCNTs) is finely dispersed in poly(propylene) (PP)/boron nitride (BN) composites with the assistance of commercial ethylene‐α‐octene block copolymer (OBC) through a conventional melt‐compounding method, whereas serious agglomeration of MWCNTs occurs in the melt compounded PP/MWCNTs/BN composites. The good dispersion of MWCNTs facilitates the formation of a better conductive network to synergistically improve the thermal conductivity of PP/OBC/MWCNT/BN composites, up to 1.71 W m −1 K −1 at a BN content of 20 vol%. Meanwhile, the elastomeric OBC component leads to markedly enhanced impact toughness (>8.0 kJ m −2 ) and elongation at break (>23%) of the composites. This work sheds light on the fabrication of thermally conductive polymer composites with balanced mechanical performance through a conventional processing technique.