Constructing of strawberry-like core-shell structured Al2O3 nanoparticles for improving thermal conductivity of nitrile butadiene rubber composites

In this paper, we have designed strawberry-like core-shell structured aluminum oxide/tannic acid-ferric ion/ silver (Al2O3/TA-Fe3+/Ag) nanoparticles (NPs) and incorporated them into nitrile butadiene rubber (NBR) matrix to obtain thermally conductive composites. The tannic acid (TA) provided a strong binding affinity to the surface of Al2O3 NPs and formed a stable octahedral complex with Fe3+. Moreover, the TA layer enhanced interfacial interactions and compatibility between thermally conductive filler and NBR matrix, leading to reduced phonon scattering and decreased interfacial resistance of NBR composites. As a result, the incorporation of Ag NPs on the surface of Al2O3/TA-Fe3+ enhanced the thermal conductivity (?) of NBR composites. The results revealed that the ? of 50 vol% Al2O3/TA-Fe3+/Ag/NBR composite was 0.90 W/mK, which was 600% of pure NBR (0.15 W/mK). Meanwhile, the dielectric constant (Cr) of 50 vol% Al2O3/TA-Fe3+/Ag/NBR composite reached up to 12.91 at 102 Hz. However, the volume resistance of all Al2O3/TA-Fe3+/Ag/NBR composites was larger than 1.97 ? 1011 0 mm. Overall, the proposed low-cost and green surface modification method provides novel insights into the design of advanced polymeric composites with high ? for large-scale production.

Automated summary

A novel thermally conductive composite was designed by incorporating aluminum oxide/tannic acid-ferric ion/silver nanoparticles into an NBR matrix, improving the thermal conductivity and dielectric constant of the material. The research showed that this method effectively enhances the thermal conductivity of the composite material, with significant potential for practical applications.