Characterization of cellulose nanowhiskers extracted from alfa fiber and the effect of their dispersion methods on nanocomposite properties

In this study, cellulose nanowhiskers (CNW) were prepared from alfa fiber (Stipa tenacissima) by an alkali treatment at room temperature in association with a bleaching treatment followed by a sulfuric acid hydrolysis. Fourier Transform Infrared (FT-IR) spectroscopy was used to highlight the evolution of chemical composition. Atomic Force Microscopy and Zeta-sizer indicated that the transverse size of the particles varied between 30nm and 170nm. Thermal stability was higher for CNW as compared to alfa fiber. FT-IR, X-ray diffraction, and Thermogravimetric analysis studies confirmed the removal of hemicelluloses and lignin during the chemical treatment process. The swelling of CNW in water with Cloisite 30B (CNW/C30B) or with the Polyethylene glycol (CNW/PEG) was carried out. The properties of Polyvinyl Chloride (PVC) nanocomposites reinforced with CNW which was dispersed with two different methods were also compared. The results showed that the morphology of both samples have drastic differences which may explain the fact that the storage modulus prepared with CNW/C30B was higher than those prepared with CNW/PEG. However, PVC/CNW/PEG nanocomposites exhibited more thermal stability. In the end, the obtained CNW may have potential applications in alternative power sources as a reinforcement phase.