Synthesis and Characterization of Functionalized Fe3O4/Boron Nitride as Magnetically Alignable 2D-Nanofiller to Improve the Thermal Conductivity of Epoxy Nanocomposites

In the electronic industry, there is an enormous request for high thermal conductivity polymer. In this regard, we propose a novel synthesis route to produce magnetically alignable 2D-nanofiller. In our work, surface modification of boron nitride nanosheets (BNNs) with polyacrylamide brushes are explored. For this purpose, the post-polymerization reaction of BNNs is followed by the redox polymerization of acrylamide onto the surfaces of already hydroxyl-functionalized BNNs. Afterward, magnetic iron oxide nanoparticles are contributed to modified BNNs through polyacrylamide chelating effect. Finally, to provide high thermal conductive and magnetic responsive nanocomposites, the functionalized Fe 3 O 4 /BNNs are dispersed in epoxy matrix and aligned under an external magnetic field. According to the results of thermal conductivity studies, thermal transport of the nanocomposites increases to 0.37 W/mK by adding only 10% of functionalized Fe 3 O 4 /BNNs (at 25 °C). Mechanical and thermal properties of these nanocomposites are compared with the pristine epoxy polymer as a control sample.