落叶松木素的特性

The Characteristics of Chinese Larch Lignin

用红外、紫外光谱仪,元素分析仪、~1H-NMR、^(13)C-NMR和化学分析方法,对落叶松心材木素特性进行了研究,与边材和云杉相比,心材MWL含有更多的酚羟基、醌、共轭羰基和缩合芳环结构,它们与苯环形成了复杂的共轭发色体系。心材木素中含有不可抽提的双氢黄酮类多酚物质。文中还介绍了落叶松木素在磺化和漂白过程中的一些特性。

The characteristics of Chinese larch heartwood lignin were determined by IR, UV spectrometry. ~1H-NMR, ^(13)C-NMR and chemical analyses. Larch heartwood MWL was found to contain more phenolic hydroxyl groups, quinoids, polyphenol structures conjugated benzyl rings and complex chromogen systems than larch sapwood. The same conclusions were drawn, when compared with spruce. C_9 formulas for larch heartwood and sapwood MWL were suggested to be C_9H_(9.95)O_(1.87)(OCH_3)_(0.61)and C_9H_(8.30)O_(3.00)(OCHa)1.4 respectively. It was found through SEM-EDXA analysis that the degree of sulfonation in the secondary wall was higher than that in the middle lamella for chinese larch NS SCMP fibers, indicating the differences in structure and reaction properties of lignin at these sites. The behavior of Chinese larch heartwood lignin in bleached SCMP was also studied by IR spectrometry. The major reason for much higher H_2O_2consumption was the presence of more quinones, conjugated carbonyl groups and phenolic hydroxyl groups in larch heartwood lignin.