(359f) Fused Filament Fabrication of Conducting Nanocomposites Based on Reduced Graphene Oxide/Polymer Blends

Adding functionality to 3D printed specimens presents a significant opportunity to benefit from the advantages of additive manufacturing while expanding utility of printed parts beyond structural components. Here, conducting composite filaments consisting of a blend of thermoplastics, including poly(methyl methacrylate) and other engineering copolymers, and reduced graphene oxide (rGO) were created via a solution casting process and used in fused filament fabrication. To promote intimate mixing, graphene oxide was reduced in a solution containing the matrix polymer and subsequently coprecipitated to produce a well-dispersed nanocomposite material. This strategy provides the capacity to vary the amount of the rGO additive incorporated in the blend and significantly change the electrical conductivity of the materials. Assessments of printing by fused filament fabrication demonstrate that the brittle nature of filaments necessitate the addition of polymeric plasticizers that enhance printability by altering rheological properties and compatibility. Ultimately, printed parts show increases in thermal and electrical conductivity with increasing rGO loading level, as well as changes in mechanical properties associated with the incorporation of the nanofiller rGO. In total, the results demonstrate the utility of the solution casting method as well as the opportunities to provide functionality based on the current-carrying capacity of the FFF-printed parts.