阳离子蔗渣半纤维素的合成及表征

以从蔗渣中提取的半纤维素为原料、3-氯-2-羟丙基三甲基氯化铵为阳离子试剂、乙醇/水为反应介质,通过季铵化反应制备了阳离子蔗渣半纤维素聚合物.通过改变反应条件合成了一系列水溶性好、取代度在0.002~0.02之间的阳离子半纤维素.采用傅立叶红外光谱和13C核磁共振表征了改性半纤维素的结构,并利用凝胶渗透色谱检测了改性前后半纤维素的相对分子质量,发现改性后半纤维素的相对分子质量有所降低.最后利用同步热分析仪测定了改性前后半纤维素的热稳定性,发现改性后半纤维素的热稳定性下降.

Synthesis and Characterization of Cationic Sugarcane Bagasse Hemicelluloses

A kind of cationic polymer was synthesized by means of quaternization,with sugarcane bagasse hemicelluloses as the raw material,3-chloro-2-hydroxypropyltrimthylammonium chloride as the cationic reagent and ethanol/water mixture as the reaction system.By optimizing the synthesizing conditions,a series of soluble cationic hemicelluloses with the degree of substitution from 0.002 to 0.02 were prepared.The structure of the modified hemicelluloses was then examined by means of FT-IR and 13CNMR,and the relative molecular masses of the hemicelluloses before and after the modification were measured by means of GPC,revealing a decreased relative molecular mass after the modification.The thermal stabilities of the hemicelluloses before and after the modification were finally studied by using a simultaneous thermal analyzer.The results show that the thermal stability of the modified hemicelluloses decreases.