Thermal conductivity and thermo-physical properties of nanodiamond-attached exfoliated hexagonal boron nitride/epoxy nanocomposites for microelectronics

This research focused on evaluating the thermal and physical properties of a composite reinforced with nanodiamonds and epitaxial boron nitride in an epoxy matrix. Nanodiamond-attached exfoliated hexagonal boron nitride nanoplates were fabricated using 4,4′-methylene diphenyl diisocyanate as the coupling agent. The morphology and structure of boron nitride (BN), exfoliated hexagonal BN nanoplates (EBN), and nanodiamond-attached EBN nanoplates (NDEBN) were determined. Epoxy composites were fabricated by in-situ polymerization and reinforced with various concentrations of either EBN or NDEBN nanoplates. These composites exhibited high thermal stability and high thermal conductivity, attributed to the exceptional thermal stability and thermal conductivity inherent in nanodiamond materials. In addition, inserting nanodiamond particles between BN layers prevented the BN nanosheet from forming agglomerates. We also found that nanodiamond particles improved dynamic mechanical properties by acting as a crack pinning role, which could restrict the molecular mobility of the epoxy.