纤维素氨基甲酸酯的制备及再生膜的应用

以常用廉价溶剂N,N-二甲基乙酰胺(DMAc)为介质,以纤维素和尿素为原料,制备了纤维素氨基甲酸酯(CC),采用红外光谱、X射线衍射、扫描电镜等对产物的结构进行了表征,并对纤维素再生膜的截留性能进行了研究。结果表明,制备纤维素氨基甲酸酯的最佳反应条件为160℃,8 h;酯化前后,纤维素晶型没有发生明显的变化;制备的纤维素再生膜具有孔径很小的微孔,这些微孔能够使H_2O和Na_2SO_4在压力的作用下顺利通过,而对亚甲基蓝有良好的截留效果;因此,纤维素再生膜对含亚甲基蓝的废水具有良好的分离效果。

Preparation of Cellulose Carbamates and Applications of Their Regenerated Membranes

N,N-dimethylacetarnide(DMAc),a common and inexpensive solvent,was chosen as medium,cellulose carbamates(CC) were successfully prepared by the reaction of cotton pulps and urea.The structures of samples were characterized by Fourier transform infrared spectroscopy (FT-IR),scanning electron microscopy(SEM) and X-ray diffractometry(XRD).The filtration performance of the regenerated membranes was also studied.The results show that the optimum reaction condition for preparing CC in DMAc is 160 ℃ for 8 h.It is found that the crystal forms of cellulose are not changed after esterification.It is also shown that there are a large number of tiny holes on the membranes that allowing small molecules,such as H2O and H2SO4,to pass through,methylene blue with a larger size than water molecules,however,is rejected.Undoubtedly,the regenerated membranes have good separation performance for wastewater containing methylene blue.