Alwadani Norah S, Fatehi Pedram
Chemical Engineering Department Lakehead University Thunder Bay ON Canada P7B5E1.
ChemistryOpen. 2019 Oct 10;8(10):1258-1266. doi: 10.1002/open.201900263. eCollection 2019 Oct.
Kraft lignin (KL) is extensively produced in industry but is mainly burned as fuel. To broaden its use, KL was grafted with dodecyl glycidyl ether to alter its thermal properties. The reaction of KL with dodecyl glycidyl ether (DGE) was analyzed using nuclear magnetic resonance (NMR), Fourier infrared spectroscopy (FT-IR) and elemental analysis. Alternatively, KL was methylated to mask its phenolic hydroxy groups to investigate how phenolic hydroxy groups impact the grafting of the alkyl chain of DGE onto lignin (methylated Kraft lignin, MKL). The methylation facilitated the molecular weight enhancement and thermal stability reduction of Kraft lignin via grafting with DGE. The influence of grafting alkyl chains on the structural and thermal properties of KL and MKL was studied using thermogravimetric analysis and differential scanning calorimetry analysis. Our data suggest that, due to their high molecular weights and lower glass transition temperatures, the produced lignin derivatives may be promising feedstocks for composite production.
硫酸盐木质素（KL）在工业上大量生产，但主要作为燃料燃烧。为了拓宽其用途，将十二烷基缩水甘油醚接枝到KL上以改变其热性能。使用核磁共振（NMR）、傅里叶红外光谱（FT-IR）和元素分析对KL与十二烷基缩水甘油醚（DGE）的反应进行了分析。另外，将KL甲基化以掩盖其酚羟基，以研究酚羟基如何影响DGE的烷基链接枝到木质素上（甲基化硫酸盐木质素，MKL）。甲基化通过与DGE接枝促进了硫酸盐木质素的分子量增加和热稳定性降低。使用热重分析和差示扫描量热分析研究了接枝烷基链对KL和MKL的结构和热性能的影响。我们的数据表明，由于其高分子量和较低的玻璃化转变温度，所制备的木质素衍生物可能是用于复合材料生产的有前途的原料。
