粘度法测定竹材薄壁组织和维管束中纤维素的分子量

1.中南林业科技大学材料科学与工程学院,湖南长沙 410004;2.竹业湖南省工程研究中心,湖南长沙 410004

薄壁组织;维管束; PTC;VBC;粘度;分子量

Determination of molecular weight of parenchymal tissue and vascular bundle cellulose in bamboo by viscosimetry
HONG hong1, ZHOU Weihong1, YU Yunshui1, 2, JIA Chunhua1

1. School of Materials Science and Engineering, Central South University of Forestry &Technology, Changsha 410004, Hunan, China; 2. Hunan Provincial Engineering Research Center of Bamboo Industry, Changsha 410004, Hunan, China

parenchymal tissue; vascular bundle; PTC; VBC; viscosity; molecular weight

DOI: 10.14067/j.cnki.1673-923x.2017.01.019

备注

为测定竹材薄壁组织和维管束中纤维素的分子量,通过从毛竹中分离出薄壁组织和维管束,分别从中提取出纤维素,采用铜乙二胺 (CED)粘度法再对两组织中提取出的 PTC和 VBC分子量进行测定。结果 表明: VBC分子聚合度为 1 001,粘均分子量达到 1.6×105,远高于 PTC分子;将得到的结果与 XRD测定结果对比,表明测得的 VBC结晶度为 67.9%,大于 PTC的 60.3%,纤维素大分子的晶区比例 (结晶度 )随着纤维素分子量的增加而增大。因此,维管束更适于作为制取竹纤维的原料。

To measure the molecular size of cellulose between parenchymal tissue and vascular bundle in bamboo, in this research, the molecular weight of parenchymal tissue cellulose (PTC) and vascular bundle cellulose (VBC) extracted from parenchymal tissue and vascular bundle were determined by CED viscosimetry. The results showed that the VBC polymerization degree was 1001, and the viscosity average molecular weight (Mη) reached 1.6×105, much higher than that of PTC molecular’s. Meanwhile, the obtained results were compared with the XRD results, the comparison showed that the crystallinity of VBC was 67.9%, higher than PTC with a crystallinity of 60.3%, suggesting that the ratio of crystalline region in cellulose macromolecule increased with the increase of the molecular weight. As a result, the vascular bundle is more suitable for producing bamboo fiber.