Preparation and characterisation of 3D printed bio-composites containing <i>Carica papaya</i> cellulose nanofibres

For the first time, cellulose nanofibres (CNFs) were extracted from Carica papaya petioles using chemo-mechanical treatment. The obtained nanofibres were characterised by using field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis. The morphological studies confirmed the nanofibre dimensions in the range of 10-60 nm. The CNFs were used at low levels (1%) as a reinforcement in polylactic acid (PLA) matrix to prepare the filaments for 3D printing using the extrusion process. The filaments were then used to print PLA/CNFs bio-composite specimen using fused filament fabrication (FFF) process. The mechanical and thermal properties of the PLA/CNFs composite parts were determined. The tensile strength (10.8%) and elastic modulus (21.9%) of PLA parts were significantly improved by addition of petiole CNFs.