Ogunjobi Joseph K, Adewale Adetola I, Adeyemi Samson A
Department of Chemistry, Federal University of Technology, PMB 704, Akure, Nigeria.
Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Science, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa.
Heliyon. 2023 Jan 20;9(1):e13104. doi: 10.1016/j.heliyon.2023.e13104. eCollection 2023 Jan.
The use of biomass for the development of environmentally friendly and industrially useful materials is still attracting global interest. Herein, cellulose nanocrystals were prepared from Siam weed. The production steps involved dewaxing the biomass sample, bleaching treatment, alkali treatment and acid hydrolysis. The resulting cellulose nanocrystals were characterized using Fourier transformed infrared (FTIR) spectroscopy, X-ray diffraction (XRD) spectroscopy, thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS) technique. Chemical composition results showed that Siam weed contained 39.6% cellulose, 27.5% hemicellulose, 28.7% lignin and 4.2% extractive. FTIR spectrum confirmed the presence of cellulose and absence of lignin and hemicellulose while XRD analysis revealed that the cellulose nanocrystals have crystallinity index of 66.2% and particle size of 2.2 nm. TGA revealed that thermal stability of raw Siam weed is lower than that of its cellulose nanocrystals due to the presence of the non-cellulosic component with lower temperature of degradation. SEM revealed that degradation of cellulosic chain had occurred. TEM confirmed that the crystal size is in the nanoscale with an average size <100 nm. DLS data revealed a nanocellulose with an average hydrodynamic size of 213 nm and a zeta potential at -9.57 mV.
利用生物质开发环境友好型和工业用材料仍然吸引着全球的关注。在此，从飞机草中制备了纤维素纳米晶体。生产步骤包括对生物质样品进行脱蜡、漂白处理、碱处理和酸水解。使用傅里叶变换红外（FTIR）光谱、X射线衍射（XRD）光谱、热重分析（TGA）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）和动态光散射（DLS）技术对所得纤维素纳米晶体进行了表征。化学成分结果表明，飞机草含有39.6%的纤维素、27.5%的半纤维素、28.7%的木质素和4.2%的提取物。FTIR光谱证实了纤维素的存在以及木质素和半纤维素的不存在，而XRD分析表明纤维素纳米晶体的结晶度指数为66.2%，粒径为2.2纳米。TGA表明，由于存在降解温度较低 的非纤维素成分，未加工飞机草的热稳定性低于其纤维素纳米晶体。SEM表明发生了纤维素链的降解。TEM证实晶体尺寸处于纳米级，平均尺寸<100纳米。DLS数据显示纳米纤维素的平均流体动力学尺寸为213纳米，ζ电位为-9.57毫伏。
