Synthesis, and Characterization of Cellulose Nanocrystal (CNC) From Corncob /PVA Based Nanocomposite

Abstract

Abstract The study has been carried out to investigate the effect of incorporating corncob cellulose nanocrystals in polyvinyl alcohol (PVA) matrix with the aim of enhancing the mechanical properties of PVA for reinforcement purposes. Cellulose nanocrystals were extracted from corncob by the method of sulfuric acid hydrolysis, with the objective of achieving maximum yield (41.8%) of cellulose nanocrystal found at the parameter interaction of 65wt.% sulfuric acid concentration,45℃ reaction temperature, and 60 minutes of hydrolysis time. Fourier transform infrared showed that Cellulose nanocrystals prepared from the hydrolysis of the isolated cellulose in the sulfuric acid had needle-shaped morphology, an average length of 170.3nm, and a crystallinity index of 79.3%. The crystallinity index obtained from x-ray diffraction for cellulose nanocrystal was found higher than extracted cellulose with a value of 79.3% and 76.4% respectively. Thermal stability by thermogravimetric analysis showed that the degradation temperature of the cellulose nanocrystals reached around 327℃, which was higher than that of the raw corncob and extracted corncob cellulose. Nanocomposite films were prepared by solution casting technique using 2, 4, and 6 wt% cellulose nanofillers, using pure PVA as the basis for the study. Parameters such as tensile strength, elongation, and elastic modulus were studied, and significant improvements in the properties of polyvinyl alcohol films containing cellulose nanofillers were observed. The tensile strength and modulus of PVA-reinforced nanocellulose composites were significantly improved with increasing nanocellulose loading. Therefore, dispersing 6% by weight of nanocrystalline cellulose in polyvinyl alcohol polymer increased tensile stress by 17.9% and modulus by 67.15%. 6 wt. The increase in elongation at break was 56.7% when using cellulose nanocrystals (CNC). Thermogravimetric analysis results of 6 wt% CNC-enhanced PVA show that high weight loss (approximately 84% weight loss of total weight) occurred in the temperature range from 265.6 to 491.61°C.