New Cellulosic Fibers from Washingtonia Tree Agro-wastes: Structural, Morphological, and Thermal Properties

Washingtonia is a palm tree that enriched with lignocellulosic biomass, which provided it with the potentiality for various applications. In this study, different biomass from Washingtonia plant, i.e. leaf stalk (W-LS), trunk core (W-TC), and trunk spine (W-TS) fibers, were collectively investigated by characterization. Under scanning electron microscopy (SEM) examination, the spine-shape structure of W-TS fiber along with its small particle size might facilitate it for fabrication reactivity. From chemical and elemental composition analysis, both W-TC and W-TS fibers were found with high cellulose content, while with the closely similar residual elements, suggesting them from the same source of trunk segment. However, the low cellulose content of W-LS fiber with its high ash content had somehow reduced its crystallinity and thermal stability properties. From X-ray diffraction (XRD) analysis, the crystallinity was estimated the highest for W-TS (68.2%), and while with the lowest for W-LS fiber (57.3%), which in line with the detected functional groups by Fourier Transform Infrared-ray (FTIR) spectrophotometry. In thermogravimetry (TGA) analysis, all fibers possessed great thermal resistance with T_onset in the range of 307.4–328.1°C and T_peak in the range of 352.4–347.9°C. Washingtonia fiber had a high potential to be applied as a bio-material for versatile applications in the future.