Effect of Chemical Treatments Sequence on Crytallinity oh Sorghum-Based Micro-Fibrillated Cellulose

Development of micro-fibrillated cellulose (MFC)-derived from natural fiber is continuously gaining interest to produce an environmentally friendly material. Accordingly, sorghum is one of the most-cultivated crops that usually remain the bagasse as byproduct of bioethanol production. Indeed, it will be a promising area to utilize sorghum bagasse to produce MFC for enhancing polymer performance, especially in terms of crystallinity. In this study, a sequence of chemical modification was applied to sorghum fibers, i.e. alkalization using 10% sodium hydroxide followed by bleaching using 1.7% sodium chlorite then sulfuric acid hydrolysis. The treatment was objected to unbundle the lignocellulose networks into MFC with less amorphous part and lower hydrophilic properties. Evaluation of the chemical treatments effect on crystallinity index of sorghum fiber was measured via X-ray Diffraction (XRD) and supported by morphological image from Field-Emission Scanning Electron microscope (FE-SEM) and chemical characterization from Fourier Transformation Infra-Red (FTIR) Spectroscopy. The experiments show that production of sorghum-based MFC sized 3-4 ¼m was successfully carried out and enhanced crystallinity index from 41% to 80% due to removal of amorphous part include hemicellulose and lignin.