Fabrication and characterization of a filament for 3D printing from polylactic acid with <i>Cryptostegia grandiflora</i> fiber

Abstract Additive manufacturing (AM), i.e., 3D printing, has seen significant growth in recent years in all industries due to its potential advantages, requiring the polymers that are adapted as for melt flow index (MFI) to this use to have adequate tensile strength as well. Hence, in this work, a novel ligno-cellulosic fiber from Cryptostegia grandiflora (CG) and polylactic acid (PLA) were blended to obtain a filament for AM using a twin screw extruder. To determine the filament’s suitability for the 3D printing process, MFI and thermal degradation were examined. In order to identify the distribution and the effect of CG fiber (CGF) filler on the matrix, the filaments were examined using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). CGF powder distribution was observed in the microstructure of the CGF/PLA composite filament. Due to the high compatibility between PLA and CGF, their blending slightly increased the degradation temperature, though did not lead to any crystallinity loss, and the CGF/PLA filament showed 12.5% better tensile characteristics than the pure PLA filament. Based on their performance, the CGF may represent a suitable and compatible filler to improve the properties of the PLA filament for 3D printing applications.