【作者】 赵延霞；

【导师】 王宗廷；

【作者基本信息】 中国石油大学 ， 应用化学， 2008， 硕士

【摘要】 单纯的单体共聚所得的聚脒存在分子量小、成本高的缺点,使其在应用中受到很大程度的限制。淀粉分子带多个羟基,易于实现酯化、醚化、氧化、交联、接枝等反应,而且淀粉接枝共聚物在高分子絮凝剂、高吸水材料、造纸工业助剂、油田化学材料、可降解地膜和塑料等多方面的实际应用中具有优异的性能。因此本课题开展淀粉接枝聚脒方法的研究,以合成出分子量大、成本低的阳离子絮凝剂。以天然多羟基高分子物质——淀粉为原料,首次通过交替接枝丙烯腈、N-乙烯基甲酰胺双乙烯基单体制备淀粉接枝聚脒。本研究主要采用水溶液接枝聚合生成中间体,再在酸性介质中直接脒化的工艺,优化了各项反应条件,具体为:(1)中间体接枝聚合的条件为:淀粉11.1%(wt),采用双引发剂用量为0.440%(wt),单体AN与NVF质量比1:1,反应温度50℃,反应时间5h。(2)脒化条件为:盐酸用量11.1%(wt),脒化温度95℃,脒化时间1.5h。用FT-IR分别对可溶性淀粉、接枝中间体、接枝聚脒的结构组成进行了表征,对产品的性质——电荷密度和特性粘度进行了研究和评价。结果表明两种单体AN和NVF成功地接枝在了淀粉上,成功合成出了淀粉接枝聚脒;所得到的接枝聚脒的特性粘度为1.94dL·g-1,电荷密度为2.29mmol·g-1。此外,对产物的絮凝性能进行了评价——对处理城市生活污水的研究发现,接枝聚脒的添加量为25.0mg·L-1时,其处理污水的浊度为4.2NTU;对采油含聚污水的油水分离的研究表明,接枝聚脒的加入量达50.0mg·L-1时,含油量从原来的1043.16mg·L-1降低到20.0mg·L-1,均表现出优异的处理效果。此外还做了单引发剂接枝聚合,尝试了种子聚合等其它聚合方法,取得了一定的效果。在此基础上研究了淀粉接枝共聚反应中引发剂、淀粉、单体浓度的变化对接枝效率和接枝共聚反应速率的影响,确定了接枝反应速率及表观活化能。从目前查阅的资料来看,淀粉接枝聚脒的研究在国内、外均未见文献报道,有重要创新。但是由于脒化在酸性条件下进行,因此存在淀粉的水解、收率低等问题。由于实验时间的限制暂时未能找到更好的解决办法,以后有待于进一步研究。更多还原

【Abstract】 The polyamidine being made by direct co-polymerization of N-vinyl formamide(NVF) and acrylonitrile(AN) was in low-molecule and high cost, so it’s appling was restricted. Because starch with many hydroxy groups is abundant, it’s easy to esterificatien and graft. In order to descend the cost and ascend the molecule, this paper was studied on polyamidine grafted with starch.Starch grafted polyamidine was made from starch grafting NVF and AN. In this paper, aqueous solution polymerization and the direct acetamiprid in acid medium were studied. (1)The optimized reaction conditions of intermediate were: the starch percent of 11.1%(wt); the initiator percent of 0.30%(wt); m(NVF):m(AN)=1:1; the polymerization temperature of 50℃; the polymerization time of 5h. (2)The optimized reaction conditions of acetamiprid were: the HCl percent of 11.1%(wt); the formamidine temperature of 95℃; formamidine time of 1.5h.The co-polymer and graft polyamidine were characterized by FT-IR. The properties of the graft polyamidine such as reduced viscosity and charge density were determined. It was found that the reduced viscosity of graft polyamidine was 1.94dL·g-1, it’s charge density was 2.29mmol·g-1. The applied properties of the graft polyamidine such as the turbidity, COD and the percent of oil in the oil water seperation were determined. The results were satified that when grafted polyamidine for 25.0mg·L-1, the turbidity was 4.2; when grafted polyamidine for 50.0mg·L-1, the percent of oil in the oil water was 20.0mg·L-1.Additional, seed polymerization and other polymerization methods were also tried, which had yielded certain results. Furthermore, the influence of changes of concentrations of initiator, starch, monomer on graft efficiency and co-polymerization rate was studied during the co-polymerization reaction. Also the apparent activation energy was obtained.At present, this research is absolutely new. It’s experement method and results are not recorded within national and international documents. But the formamidine is experemented in acid medium, so the decomposition of starch is serious. In order to solve this problem, the further research will be studied in future.更多还原