DISSOLUTION OF ETHYLENEDIAMINE-PRETREATED LIGNOCELLULOSIC MATERIAL IN LICL/DMSO AND PREPARATION OF LIGNOCELLULOSE AEROGELS

摘要

Various lignocellulosic materials,such as hardwood and softwood kraft pulps (HKP,SKP),including those with relatively high lignin content (up to ca.10.5%),can be solubilized without milling in lithium chloride/ dimethyl sulfoxide (LiC1/DMSO) by ethylenediamine (EDA) pretreatment.Because milling of the sample is not required,mechanical degradation of the cell wall components can be avoided.After the EDA pretreatment,the crystallinity of the celluloses remained as high as the original celluloses,although:the crystal structure changed.Therefore,the formation of cellulose-EDA complex seems to be critical for dissolution in the LiCl/DMSO solvent. Through this pretreatment,lignocellulosic hydrogels and aerogels were prepared from lignocellulose from 8% LiCl/DMSO solvent system.SEM observation revealed the gel's nanofibrillar network,characterized by fairly uniform fibrils about 20-30 nm wide and 1001000 nm long segments.