3D printed polylactic acid/graphene nanocomposites with tailored multifunctionality towards superior thermal management and high-efficient electromagnetic interference shielding

The relative lack of printable materials with tailored functionalities limits the development of three-dimensional (3D) printing techniques. Herein, a promising multifunctional filament was fabricated by incorporating graphene nanosheets (GNs) into polylactic matrix via a solution-blending method. With this strategy, the uniform-distributed GNs were obtained in the matrix, even with a high GNs concentration (9.08 vol%). The resultant nanocomposites exhibited desired functionalities, that the thermal conductivity (Tc) was up to 3.22 W/m·k, more than ten times that of pure one (0.25 W/m·k), and the electromagnetic interference shielding (EMI SE) reached 34.9 dB at X-band region, meaning 99.97 % shielding efficiency to EWMs energy. Thereafter, by tapping into the manufacturing potential of 3D printing, a series of ideal parts featuring arbitrarily designated structures and exceptional performance was constructed. Particularly, the 3D-printed heat sinks possessed outstanding behaviors in thermal management, where the corresponding initial dissipating rate achieved a 266 % improvement over that of the pure one. Besides, the 3D-printed shielding module posed high-efficiency EMI SE performance, corresponding to 35.8 dB at a specific Bluetooth-interaction signal (2.4 GHz). Overall, this innovative study not only enriches the printable materials with tailored multifunctionality but also brings the promising potential for applications in the next-generation functional parts.