竹纤维素分离级分的结构特性

Structural characteristics of bamboo cellulose fractions

为促进竹纤维素的高效利用,研究了竹纤维分级分离所得3种竹纤维素级分的结构特性。结果表明,随着分离级数增加,纤维素分子链发生断裂的程度加剧,重均相对分子质量MW值逐渐减小。第一级、二级和三级纤维素是高纯度的,它们的红外图谱上没有出现与木质素和半纤维素有关的特征吸收峰。经分级分离后,3种纤维素的物理结构发生了很大变化,其纤维表面疏松多孔,且密布沟槽。从第一级、二级到三级纤维素纤维的长度和结晶度逐渐降低,而酶解效率逐渐增高。由此可见,各级竹纤维素的加工与应用特性得到改善。

To promote effective use of bamboo cellulose,the structural characteristics of three fractional bamboo celluloses by fractional separation were studied.The results demonstrated that weight-average relative molecular weight（MW） of cellulose gradually decreased because of the deepening fracture degree of cellulose molecular chain with the increasing of fractional grade.The 1st,2nd,and 3rd grade fractional celluloses are of pure ones,no typical absorption peaks related to lignin and hemicellulose appeared on their infrared spectra.After fractional separation,the physical structures of the three fractional celluloses occurred great change,many holes and ditches were distributed on the loose surface of the cellulose fibers.The length and crystalline degree of the first,second and third fractional cellulose decreased in proper order,while the enzymolysis efficiency increased gradually.Thus it can be seen that the processing and application characteristics of the first,second and third fractional cellulose may be improved.