木薯淀粉接枝丙烯酰胺絮凝剂合成方法的比较研究

Comparative study of synthetic methods of cassava starch grafted acrylamide flocculant

以木薯淀粉与丙烯酰胺单体为原材料,分别采用溶液聚合法和反相乳液聚合法制备淀粉接枝丙烯酰胺絮凝剂(St-PAM),并进行性能比较。结果表明:在相同反应温度和单体比时,反相乳液聚合法制备的St-PAM单体转化率与接枝率均高于溶液聚合法,同时所需引发剂用量少,有利于节约成本;反相乳液聚合法合成St-PAM的接枝共聚程度高于溶液聚合法,制备的St-PAM表面粗糙程度更深、褶皱更多,更有利于吸附作用与网捕作用的进行,并且热稳定性更强;反相乳液聚合法合成St-PAM对温度、酸碱度的适应性更强,对搅拌时间与搅拌速度的需求更低。相同条件下,溶液聚合法St-PAM的絮凝率最高达到85%左右,而反相乳液聚合法St-PAM的絮凝率最高可达90%以上,说明反相乳液聚合法制备的St-PAM性能优于溶液聚合法制备的St-PAM,适用性更好。

Starch graft acrylamide flocculant(St-PAM)was prepared by solution polymerization and inverse emulsion polymerization using cassava starch and acrylamide monomer as raw materials,and the properties were compared.The results show that the monomer conversion and grafting rate of St-PAM prepared by inverse emulsion polymerization are higher than those of solution polymerization with the same reaction temperature and monomer ratio,and less initiator is needed,which is beneficial to cost saving.The graft copolymerization degree of St-PAM synthesized by inverse polymerization method is higher than that of solution polymerization,and it has deeper surface roughness and more wrinkles,which is more conducive to adsorption and net trapping,and has stronger thermal stability.St-PAM synthesized by inverse emulsion polymerization has stronger adaptability to temperature and pH,and lower demand for stirring time and stirring speed.Under the same conditions,the highest flocculation rate of St-PAM prepared by solution polymerization is about 85%,while that of St-PAM prepared by inverse emulsion polymerization is more than 90%,indicating that the performance of St-PAM prepared by inverse emulsion polymerization is better than that of solution polymerization.