Bloch Marta, Woźniak Magdalena, Dwiecki Krzysztof, Borysiak Sławomir, Ratajczak Izabela
Department of Chemistry, Faculty of Forestry and Wood Technology, Poznan University of Life Sciences, Wojska Polskiego 75, 60625 Poznan, Poland.
Department of Food Biochemistry and Analysis, Faculty of Food Science and Nutrition, Poznan University of Life Sciences, Mazowiecka 48, 60623 Poznan, Poland.
Molecules. 2024 Sep 6;29(17):4227. doi: 10.3390/molecules29174227.
The solvolysis reaction with ionic liquids is one of the most frequently used methods for producing nanometer-sized cellulose. In this study, the nanocellulose was obtained by reacting microcrystalline cellulose with 1-ethyl-3-methylimidazolium acetate (EmimOAc). The aim of this research was to determine the influence of various antisolvents used in the regeneration of cellulose after treatment with ionic liquid on its properties. The following antisolvents were used in this research: acetone, acetonitrile, water, ethanol and a mixture of acetone and water in a 1:1 / ratio. The nanocellulose was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM) and elemental analysis (EA). The results show that the antisolvent used to regenerate cellulose after the solvolysis reaction with EmimOAc affects its properties. Water, ethanol and a mixture of acetone and water successfully removed the used ionic liquid from the cellulose structure, while acetone and acetonitrile were unable to completely remove EmimOAc from the cellulosic material. The results of the XRD analysis indicate that there is a correlation between the ionic liquid content in the regenerated cellulose and its degree of crystallinity. Among the tested solvents, water leads to the effective removal of EmimOAc from the cellulose structure, which is additionally characterized by the smallest particle size and non-formation of agglomerates.
离子液体的溶剂解反应是生产纳米级纤维素最常用的方法之一。在本研究中，通过微晶纤维素与1-乙基-3-甲基咪唑醋酸盐（EmimOAc）反应获得纳米纤维素。本研究的目的是确定离子液体处理后用于纤维素再生的各种抗溶剂对其性能的影响。本研究使用了以下抗溶剂：丙酮、乙腈、水、乙醇以及丙酮和水1:1比例的混合物。通过傅里叶变换红外光谱（FTIR）、X射线衍射（XRD）、动态光散射（DLS）、扫描电子显微镜（SEM）和元素分析（EA）对纳米纤维素进行了表征。结果表明，与EmimOAc发生溶剂解反应后用于再生纤维素的抗溶剂会影响其性能。水、乙醇以及丙酮和水的混合物成功地从纤维素结构中去除了用过的离子液体，而丙酮和乙腈无法从纤维素材料中完全去除EmimOAc。XRD分析结果表明，再生纤维素中的离子液体含量与其结晶度之间存在相关性。在所测试的溶剂中，水能够有效地从纤维素结构中去除EmimOAc，此外其颗粒尺寸最小且未形成团聚体。
