马铃薯淀粉与醋酸乙烯酯接枝聚合影响因素的研究

以马铃薯淀粉为接枝骨架,过硫酸铵为引发剂,醋酸乙烯酯(VAc)为接枝单体进行接枝共聚。考察了不同引发剂浓度、反应温度、反应时间、单体配比、淀粉浓度对单体转化率、接枝率及接枝效率的影响,确定最佳工艺条件为:引发剂浓度18 mmol/L,反应温度60℃,反应时间3.5 h,单体配比2.5:1,淀粉浓度5%。并通过扫描电镜,X射线衍射,傅里叶红外光谱对淀粉接枝共聚物进行分析,结果表明:淀粉接枝共聚后,淀粉的微观形貌已经改变,结晶度降低且醋酸乙烯酯成功接枝在马铃薯淀粉上。

Study on Graft Copolymerization Factors of Vinyl Acetate onto Potato Starch

The graft copolymerization of vinyl acetate(VAc) and potato starch was carried out using ammonium persulfate as initiator.The effect of various conditions on the graft polymerization was studied which included initiator density,reaction temperature,reaction time,monomer allocated proportion and starch density,with the percentage of monomer conversions,starch grafted rate and efficiency as the targets,The results indicates that the optimum reaction condition: initiator density 18 mmol/L,reaction temperature 60 ℃,reaction time 3.5 h,monomer ratio 2.5:1 and starch density 5%.Finally,the existence of the graft copolymer is confirmed by the structure analysis of the starch grafting copolymerization using SEM,XRD and FTIR,with the changed micro morphologies and decreased crystalline of starch.