Additive manufacturing of carbon nanotube/polylactic acid films with efficient electromagnetic interference shielding and electrical heating performance via fused deposition modeling

In the wake of developments in 5th generation mobile communication technology and Internet of Things, traditional electromagnetic interference (EMI) shielding materials are not satisfied with the booming demand of suppressing electromagnetic pollution. In view of the characteristics of low-cost, easy-operating and functional materials applicability of fused deposition modeling (FDM), in this work, a multifunctional carbon nanotube (CNT)/ polylactic acid (PLA) film with electromagnetic shielding and electric heating properties was prepared by using FDM process. The effects of CNT content, FDM-printed film thickness, and FDM process parameters on electromagnetic shielding performance were studied. The results indicate that the additions of CNT increase the EMI shielding performance by forming the conductive paths in the CNT/PLA FDM-printed films. The EMI shielding value of the 4 wt% CNT/PLA film with a thickness of 4 mm is 68 dB at 12.3Ghz. In addition, the improved electrical conductivity provides the good electric heating performance of the CNT/PLA film. At a safe voltage (16 V), the heating temperature of the 4 wt% and 8 wt% CNT/PLA films reached 67.8 degrees C and 139 degrees C, respectively. The good repeatability and stability of CNT/PLA films for electric heating were verified. The ob-tained CNT/PLA FDM-printed films have excellent electromagnetic shielding and low-voltage electric heating properties by adjusting the CNT contents and the FDM process parameters, which expands the application po-tential of EMI shielding materials and FDM technology.