Preparation of Highly Efficient Electromagnetic Interference Shielding Polylactic Acid/Graphene Nanocomposites for Fused Deposition Modeling Three-Dimensional Printing

Herein, a novel local enrichment strategy (LES) was proposed to fabricate functional polylactic acid (PLA)/graphene nanoplatelet (GNP) nanocomposites for fused deposition modeling (FDM) three-dimensional (3D) printing by precisely manipulating the selective distribution of fillers. Experimental results showed that the PLA/GNP nanocomposites prepared using the LES method exhibited higher electrical conductivity and electromagnetic interference (EMI) shielding properties than those prepared using the conventional melt-compounding method. Particularly for EMI properties, the shielding efficiency (SE) of an LES sample prepared at 6 and 10 wt % GNPs reached 21.7 and 34.7 dB, respectively, which is an improvement of over 45% compared with the conventional ones. In addition, based on the theoretical analysis of shear field and the experimental verification of filler distribution after printing, a functional 3D printed honeycomb-like part with a porous structure, light weight, and highly efficient EMI shielding properties was successfully fabricated using the FDM 3D printing technology. A new strategy was accordingly established by manipulating the filler distribution to prepare functional filaments and parts for EMI shielding applications in this innovative study.