Enhanced thermal conductivity and self-healing property of PUDA/boron nitride micro-sheets composites with a small number of graphene nano-platelets

Self-healing polyurethane diacrylate (PUDA) composites with outstanding thermal conductivity were prepared with variable boron nitride (BN) and a small number of graphene nanoplatelets (GNPs) (1 wt%). The thermal conductivity of PUDA composites containing 1 wt% GNPs and 29 wt% BN reached 1.73 W/(m·K), showing 27.2% increment compared to PUDA composites only with 30 wt% BN. BN and GNPs mutually promoted the dispersion in the PUDA matrix, and the small number of GNPs was enough to bridge the gaps between BN, so that GNPs and BN exerted a synergistic enhancement effect on the thermal conductivity of PUDA composites with a synergistic efficiency of 1.343. The PUDA composites maintained the tensile strength of 8.21 MPa with good electrical insulation (4.55 × 10⁹ Ω cm). The high degrees of recovery of mechanical strength (>90%) and thermal conductivities (>84%) were also realised by the healing effect of the reversible DA reaction. The PUDA composites with excellent comprehensive properties show broad application potential in the thermal management of electronic devices.