Pylypchuk Ievgen, Selyanchyn Roman, Budnyak Tetyana, Zhao Yadong, Lindström Mikael, Fujikawa Shigenori, Sevastyanova Olena
Division of Wood Chemistry and Pulp Technology, Department of Fiber and Polymer Technology, School of Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden.
WPI International Institute for Carbon-Neutral Energy Research (WPI-I2CNER) Kyushu University, Ito Campus, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Membranes (Basel). 2021 Mar 13;11(3):204. doi: 10.3390/membranes11030204.
Nanocellulose membranes based on tunicate-derived cellulose nanofibers, starch, and ~5% wood-derived lignin were investigated using three different types of lignin. The addition of lignin into cellulose membranes increased the specific surface area (from 5 to ~50 m/g), however the fine porous geometry of the nanocellulose with characteristic pores below 10 nm in diameter remained similar for all membranes. The permeation of H, CO, N, and O through the membranes was investigated and a characteristic Knudsen diffusion through the membranes was observed at a rate proportional to the inverse of their molecular sizes. Permeability values, however, varied significantly between samples containing different lignins, ranging from several to thousands of barrers (10 cm (STP) cm cm s cmHgcm), and were related to the observed morphology and lignin distribution inside the membranes. Additionally, the addition of ~5% lignin resulted in a significant increase in tensile strength from 3 GPa to ~6-7 GPa, but did not change thermal properties (glass transition or thermal stability). Overall, the combination of plant-derived lignin as a filler or binder in cellulose-starch composites with a sea-animal derived nanocellulose presents an interesting new approach for the fabrication of membranes from abundant bio-derived materials. Future studies should focus on the optimization of these types of membranes for the selective and fast transport of gases needed for a variety of industrial separation processes.
使用三种不同类型的木质素对基于被囊动物来源的纤维素纳米纤维、淀粉和约5%木材来源木质素的纳米纤维素膜进行了研究。向纤维素膜中添加木质素增加了比表面积（从5增加到约50 m/g），然而，所有膜的直径小于10 nm的具有特征性孔隙的纳米纤维素的精细多孔几何结构仍然相似。研究了H、CO、N和O通过这些膜的渗透情况，观察到通过膜的特征性克努森扩散，其速率与分子大小的倒数成正比。然而，含有不同木质素的样品之间的渗透率值差异很大，范围从几到数千巴（10 cm (STP) cm cm s cmHgcm），并且与观察到的膜内部形态和木质素分布有关。此外，添加约5%的木质素导致拉伸强度从3 GPa显著增加到约6 - 7 GPa，但没有改变热性能（玻璃化转变或热稳定性）。总体而言，将植物来源的木质素作为纤维素 - 淀粉复合材料中的填料或粘合剂与海洋动物来源的纳米纤维素相结合，为从丰富的生物衍生材料制备膜提供了一种有趣的新方法。未来的研究应专注于优化这些类型的膜，以实现各种工业分离过程所需气体的选择性快速传输。
