氯化酶解木质素的合成与性能研究

以酶解木质素为原料,在水相条件下通入氯气合成氯化木质素。考察了木质素与水的配比、有无紫外光催化、反应温度和通氯量对产物得率和氯含量的影响,并对产物进行了红外光谱和热重分析。结果表明,在氯气过量的情况下,产物氯含量达到29.8%,有紫外光催化时产物氯含量比较低,不加热时的产物氯含量更高,产物氯含量随氯气的增加而增大。氯化木质素的红外光谱图在1720cm-1处羰基强度明显增强,680cm-1附近出现C-Cl的特征吸收峰,说明Cl2与酶解木质素发生了取代反应。热重分析结果表明,氯化木质素的耐热性比酶解木质素稍差。与PVC共混改性的结果表明,氯化木质素改善了原有木质素分子的极性,有望作为极性高聚物共混改性的相容剂使用。

Research on the Synthesis and Properties of Chlorinated Enzymatic Hydrolysis Lignin

The synthesis and properties of chlorinated enzymatic hydrolysis lignin (EHL) were reported in this article.The influences of some factors on the yield and the chlorine content were investigated,including the mass ratio of lignin and water,ultraviolet,chlorination temperature and the dosage of Cl_2.The results showed that the chlorinated efficiency of EHL was high under the condition that the temperature was 25℃ and without the irradiation of ultraviolet,the chlorination level could be controlled by the dosage of Cl_2 and the chlorine content was increasing with the dosage of Cl_2,the highest chlorine content was 29.8%.The structure of copolymer was characterized by FT-IR,and compared with EHL.The C-Cl absorbance peak appeared about 680 cm~(-1) in IR spectra of chlorinated lignin,which indicated that the hydrogen of phenyl rings were replaced by Cl_2.Based on the TG graph,the heat-resistant of chlorinated enzymatic hydrolysis lignin Was worse than that of EHL.Molecular polarity of lignin Was improved by chlorination.Chlorinated EHL could be used as a compatibilizer between lignin and polar polymers.