Desenvolvimento de filamentos para impressão 3D (de hélices de drones) a partir de nanocompósitos poliméricos Poli (ácido láctico) e nanotubo de carbono

Abstract

The use of drones is currently growing exponentially, whether for recreational or commercial activities, and one of the biggest problems is access to some components such as the propeller. It usually has a fragile construction and the prices can be high, making access to this item difficult, which is essential for good use of the drone. The work aims to obtain polymeric nanocomposites polyacidolactic acid and carbon nanotube with a view to application in drone propellers produced through 3D printing. In the literature there is still very limited information available about the incorporation of functionalized CNT in 3D printed PLA parts produced by FFF. In this work, a filament based on Poly(lactic acid) – PLA/carbon nanotube (CNT) composites was prepared for the fused deposition modeling (FDM) process. The effects of the CNT content, temperature variation and rotation variation of the extruder screws were applied to the Design of Experiments (DOE) tool, where the main factors that contribute to the quality of the filament were found, with a focus on mechanical resistance. Using this tool, it was possible to reach an optimum point for the material's mechanical resistance, where it presented a value of 48.87 MPa, 43.17% above the initial value of 27.77 MPa. Using the response surface curve, the region where new filaments with mechanical resistance values similar to those found in this work can be found was observed. The results demonstrate that the CNT content, the rotation of the extruder screws and the extruder temperature directly influence the quality of the filaments. The data found in the TG and DTG curves allows us to observe that the addition of 0.6% CNT by weight does not significantly modify the resistance to PLA degradation, even if there is a small difference in temperatures. The main reason for these changes is the dispersion of the CNT over the PLA matrix and the glomeration of the CNT. The nanocomposite found mechanically resembles other materials used in the manufacture of plastic injection of drone propellers, making it a strong competitor for the manufacture via FDM additive manufacturing. Through the simulation demonstrated, it is possible to confirm the application of the material developed in the manufacture of drone propellers, facilitating access and providing new opportunities for users.