【摘要】 采用搅拌球磨机对玉米淀粉进行机械活化,以不同活化时间玉米为原料、过硫酸铵-亚硫酸氢钠为引发剂、丙烯酰胺为单体制备淀粉接枝共聚物,并以接枝共聚物的接枝率(G)和接枝效率(GE)为评价指标,分别考察机械活化时间、反应时间、反应温度、引发剂用量及单体用量等因素对淀粉与丙烯酰胺接枝共聚反应的影响。结果表明:机械活化对玉米淀粉的接枝共聚反应有显著的强化作用,活化时间越长,G和GE越高。其他因素对淀粉接枝共聚反应的影响规律受活化时间的制约,活化时间越长,反应对温度、引发剂及单体浓度的依赖性越低。更多还原

【Abstract】 Maize starch was mechanically activated by a stirring-type ball mill. Using ammonium persulfate-sodium bisulfate as initiator, acrylamide as monomer, graft copolymer was synthesized from maize starch with different activation time. The effects of mechanical activation time, reaction time, reaction temperature, initiator amount and monomer amount on graft copolymerization of maize starch were investigated respectively by using grafting rate (G) and grafting efficiency (GE) of graft copolymer as evaluating parameter. The results indicated that mechanical activation considerably enhanced the graft copolymerization of maize starch, the G and GE increased with increasing activation time. Moreover, it was also found that other affecting factors had a certain influence upon graft copolymerization and were closely related to the activation time of maize starch, and the effects of reaction temperature, initiator and monomer concentrations on graft copolymerization were reduced with increasing activation time.更多还原