Enhanced Thermal Conductivity of Graphene Nanoplatelet–Polymer Nanocomposites Fabricated via Supercritical Fluid-Assisted in Situ Exfoliation

As electronic devices become increasingly miniaturized, their thermal management becomes critical. Efficient heat dissipation guarantees their optimal performance and service life. Graphene nanoplatelets (GnPs) have excellent thermal properties that show promise for use in fabricating commercial polymer nanocomposites with high thermal conductivity. Herein, an industrially viable technique for manufacturing a new class of lightweight GnP–polymer nanocomposites with high thermal conductivity is presented. Using this method, GnP−high-density polyethylene (HDPE) nanocomposites with a microcellular structure are fabricated by melt mixing, which is followed by supercritical fluid (SCF) treatment and injection molding foaming, which adds an extra layer of design flexibility. Thus, the microstructure is tailored within the nanocomposites and this improves their thermal conductivity. Therefore, the SCF-treated HDPE 17.6 vol % GnP microcellular nanocomposites have a solid-phase thermal conductivity of 4.13 ± 0.12 ...