Nanocomposite Fabrication for FDM Printing

Figure 1: SEM image at 160 X magnification of fusion between extruded threads of PLA. Background and Research Goals

Fused deposition modeling (FDM) is a common method of 3D printing in which filament is melted and extruded onto a build platform. Currently, bond strength between deposited threads suffers as a result of the poor thermal properties of available printing materials, which also limit the usefulness of FDM printing in applications involving heat transfer. Polylactic acid (PLA) and polypropylene (PP) are two thermoplastic polymers used in FDM printing, but both exhibit low thermal conductivities. Graphene nanoplatelets (GNP) and boron nitride (BN) nanoparticles are thermally conductive particles that can be dispersed into polymer matrices to improve the material’s thermal properties. This research was focused on fabricating nanocomposites from the aforementioned thermoplastics and nanoparticle additives and extruding filaments for thermal conductivity testing. Printed samples were also tested and it was found that the additives significantly improved the thermal conductivities of both filaments and printed products. Additionally, scanning electron microscopy (SEM) revealed that the additives improved fusion between extruded threads in the printing process and that the nanoparticles in printed samples were oriented in the direction of heat flow. This research was conducted at Stony Brook Univeristy as part of the Garcia Center for Polymers at Engineered Interfaces.