竹材薄壁组织和维管束理化性质比较分析

Comparative research on physicochemical properties of the parenchymal tissue and vascular bundle in bamboo

从竹材中分离出薄壁组织和维管束,利用SEM、TG、XRD分析手段对分离出来两组织的化学组分含量、形貌特征、吸湿性、热稳定性及结晶性做了相应的比较分析研究。结果表明:薄壁组织主要成分为半纤维素,维管束的主要成分为纤维素;SEM图片显示薄壁组织为方形胞腔状,质地疏松易碎,维管束呈纤维束状,相互紧密排列;吸湿性测定结果表明,由于薄壁组织疏水性内含物含量高,而维管束亲水性羟基相对比例较高,使得吸湿能力维管束比薄壁组织要显著;TG分析表明维管束热稳定性较好,热解所需活化能较高;XRD表征结果显示薄壁组织的相对结晶度要比维管束低7.8%。

The parenchymal tissue and vascular bundle were separated from bamboo, and the chemical composition contents, morphology features, hygroscopicity, heat stability and crystallinity of two separated tissues were studied by methods of SEM, TG and XRD. The results showed that the main components of parenchymal tissues was hemicellulose and the vascular bundles was cellulose. SEM graphs showed that parenchymal tissues were with a shape of square cell and a loose and friable texture while vascular bundles are like ifber bundles and packed closely. Measure of hygroscopicity suggested that vascular bundles had a signiifcant capability of hygroscopicity than parenchymal tissues. Analysis of TG indicated that vascular bundles had a better heat stability than parenchymal tissues. XRD results showed that parenchymal tissues had a lower relative crystallinity of 7.8%than vascular bundles.