Improved thermal conductivity and electromechanical properties of natural rubber by constructing Al2O3-PDA-Ag hybrid nanoparticles

In this study, in-situ aluminum oxide-poly(dopamine)-silver (Al2O3-PDA-Ag) hybrid nanoparticles were synthesized using simple and eco-friendly approach. Al2O3 nanoparticles were first modified by PDA through mussel-inspired method, and Ag nanoparticles were then anchored on Al2O3-PDA nanoparticles surfaces through reduction of Ag+ by glucose. The as-obtained Al2O3-PDA-Ag nanoparticles were subsequently incorporated into natural rubber (NR) matrix to yield elastomer composites. The synergistic effect of Ag and Al2O3 nanoparticles resulted in high thermal conductivity of 10 vol% Al2O3-PDA-Ag/NR composite reaching up to 0.20 W/mK. This value was two-fold superior to that of pure NR (0.10 W/mK). In addition, Al2O3-PDA-Ag/NR composites showed excellent electromechanical and mechanical properties. Overall, the proposed method looks promising for future preparation of high-thermal-conductive dielectric materials.