Taflick Ticiane, Schwendler Luana A, Rosa Simone M L, Bica Clara I D, Nachtigall Sônia M B
Chemistry Institute, Federal University of Rio Grande do Sul/UFRGS, 9500 Bento Gonçalves Ave., Porto Alegre, 91501-970, Brazil; Sul-rio-grandense Federal Institute for Education, Science and Technology, 100 Copacabana Ave., Sapucaia do Sul, 93216-120, Brazil.
Chemistry Institute, Federal University of Rio Grande do Sul/UFRGS, 9500 Bento Gonçalves Ave., Porto Alegre, 91501-970, Brazil.
Int J Biol Macromol. 2017 Aug;101:553-561. doi: 10.1016/j.ijbiomac.2017.03.076. Epub 2017 Mar 18.
The isolation of cellulose nanocrystals from different lignocellulosic materials has shown increased interest in academic and technological research. These materials have excellent mechanical properties and can be used as nanofillers for polymer composites as well as transparent films for various applications. In this work, cellulose isolation was performed following an environmental friendly procedure without chlorine. Cellulose nanocrystals were isolated from the exhausted acacia bark (after the industrial process of extracting tannin) with the objective of evaluating the effect of the solvent extraction steps on the characteristics of cellulose and cellulose nanocrystals. It was also assessed the effect of acid hydrolysis time on the thermal stability, morphology and size of the nanocrystals, through TGA, TEM and light scattering analyses. It was concluded that the extraction step with solvents was important in the isolation of cellulose, but irrelevant in the isolation of cellulose nanocrystals. Light scattering experiments indicated that 30min of hydrolysis was long enough for the isolation of cellulose nanocrystals.
从不同木质纤维素材料中分离纤维素纳米晶体已在学术和技术研究中引起了越来越多的关注。这些材料具有优异的机械性能，可作为聚合物复合材料的纳米填料以及用于各种应用的透明薄膜。在这项工作中，纤维素的分离是按照无氯的环保程序进行的。从废弃的相思树皮（经过工业单宁提取过程后）中分离出纤维素纳米晶体，目的是评估溶剂萃取步骤对纤维素和纤维素纳米晶体特性的影响。还通过热重分析（TGA）、透射电子显微镜（TEM）和光散射分析评估了酸水解时间对纳米晶体热稳定性、形态和尺寸的影响。得出的结论是，溶剂萃取步骤在纤维素的分离中很重要，但在纤维素纳米晶体的分离中无关紧要。光散射实验表明，30分钟的水解时间足以分离出纤维素纳米晶体。
