Jõul Piia, Ho Tran T, Kallavus Urve, Konist Alar, Leiman Kristiina, Salm Olivia-Stella, Kulp Maria, Koel Mihkel, Lukk Tiit
Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia.
Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia.
Materials (Basel). 2022 Apr 13;15(8):2861. doi: 10.3390/ma15082861.
The production of novel materials and value-added chemicals from lignin has received considerable attention in recent years. Due to its abundant occurrence in nature, there is a growing interest in utilizing lignin as a feedstock for functional materials production, for example aerogels. Much like in the synthesis of phenol-based resins, the vacant ortho positions of the aromatic rings in lignin can crosslink with formaldehyde and form polymeric gels. After drying the hydrogels with supercritical CO, highly porous aerogels are obtained. Current study focuses on the preparation and thorough parametrization of organosolv lignins from different types of lignocellulosic biomass (aspen, pine, and barley straw) as well as their utilization for the preparation of lignin-5-methylresorcinol-formaldehyde aerogels. The thorough structural characterization of the obtained aerogels was carried out by gas adsorption, IR spectroscopy, and scanning electron microscopy. The obtained lignin-based monolithic mesoporous aerogels had specific surface areas and total pore volumes in the upward ranges of 450 m/g and 1.4 cm/g, respectively.
近年来，利用木质素生产新型材料和增值化学品受到了广泛关注。由于木质素在自然界中储量丰富，将其用作功能材料（如气凝胶）的原料越来越受到关注。与酚醛树脂的合成类似，木质素中芳香环的空邻位可与甲醛交联形成聚合物凝胶。用超临界CO2干燥水凝胶后，可得到高度多孔的气凝胶。目前的研究重点是从不同类型的木质纤维素生物质（白杨、松木和大麦秸秆）制备有机溶剂木质素并对其进行全面参数化，以及将其用于制备木质素-5-甲基间苯二酚-甲醛气凝胶。通过气体吸附、红外光谱和扫描电子显微镜对所得气凝胶进行了全面的结构表征。所得基于木质素的整体介孔气凝胶的比表面积和总孔体积分别在450 m²/g和1.4 cm³/g以上。
