Characterization of Cellulose Nanocrystals (CNC) and its Reinforcing Impact as an Additive for PLA-TPU 3D Printing Filament

This study investigates the use of cellulose nanocrystals (CNC) in 3D printing PLA-TPU polymer matrix to improve composite stiffness and flexibility. The addition of CNC to the PLA-TPU polymer matrix is expected to lower costs and enhance the development of polymer and composite materials, particularly in health and medical services. Despite substantial studies into 3D-printed composite products, the integration of nanoparticles in PLA-TPU blend has received inadequate attention in several studies. The study aims to characterize CNC's behavior and impact on PLA-TPU composite filament mechanical properties via FDM. The composite filament was produced using a twin-screw extruder and a 3D Devo Filament Maker. The mechanical performance of pristine PLA and TPU, as well as PLA-TPU mixture (80:20) samples, and the strengthening impact of CNC as an additive component of the PLA-TPU mixture were evaluated. Results showed that the PLA-TPU blend with 1% CNC increased tensile strength by 159.37% and 130.75% compared with pure PLA and TPU, respectively. Furthermore, adding CNC reinforcement to PLA-TPU resulted in a considerably higher flexural strength than pristine PLA and TPU. The study's findings indicated that adding 1% CNC fiber loading improved the mechanical characteristics and structural impact of PLA-TPU-CNC composite.