Electromagnetic and thermal properties of a non-conventional polymer nanocomposite based on thermoplastic Polylactic acid (PLA, Ingeo™) filled, in different weight percentage, with multi-walled carbon nanotubes (MWCNTs), graphene nanoplatelets (GNPs), as well as a mixture of both fillers (MWCNTs/GNPs), are analyzed. The combination of notable electrical, thermal, and electromagnetic (EM) properties of the carbon fillers, in concentrations above the percolation threshold, together with the good processability of the PLA matrix gives rise to innovative filaments for 3D printing. In particular, the shielding efficiency (SE) in the frequency range 26–37 GHz of samples increases from 0.20 dB of unfilled PLA up to 13.4 dB for composites containing MWCNTs and GNPs, corresponding to 4% and 95% of SE, respectively. The thermal conductivity of the PLA loaded with 12 wt % of GNPs is 263% higher than that of the unfilled polymer, whereas an improvement of about 99% and 190% is detected for the PLA matrix loaded with MWCNTs and both fillers, respectively. The EM and thermal characterization is combined with a morphological investigation allowing us to correlate the dispersion states of the fillers within the polymer matrix with the observed EM and thermal properties. The EM and thermal characteristics exhibited by the nanocomposites make them suitable for packaging applications of electronic devices with electromagnetic interference (EMI) shielding and thermal dissipation features.

PLA nanocomposites for fused-deposition modeling (FDM) technique are considered. Thermal and electrical conductivity of carbon-based PLA nanocomposites are investigated looking at the different morphological characteristic of the carbon nanoparticles. In particular commercial multi-walled carbon nanotubes (CNTs) and graphene nanoplates (GNPs) are considered as filler in order to realize filament for 3D printed devices for electrical and thermal application. In this paper a filler concentration up to 12% in weight is investigated. Transient Plane Source (TPS) measurements of thermal conductivity show that better heat conduction is obtained through the incorporation in the PLA matrix of carbonaceous nanostructures with predominantly two-dimensional shape (GNPs). DC electrical measurements show that the nanocomposite filled with the predominant mono-dimensional carbon nanoparticle (i.e. CNT) exhibits lower electrical percolation threshold, whereas a greater post percolation electrical conductivity is established with the two-dimensional filler (i.e. GNP). Such characteristics are to be considered in order to make robust and cost effective 3D printed device, by preferring 1D filler or 2D filler for electrical or thermal application respectively. Moreover, multiphase nanocomposites obtained with an optimized combination of CNT and GNP nanoparticles could be exploited to realize devices for joint electrical and thermal application.