阳离子型聚丙烯酰胺的双水相共聚法制备及应用研究

发布时间：2018-04-24 01:08

  本文选题：聚丙烯酰胺 + 双水相体系　； 参考：《长安大学》2017年硕士论文

【摘要】：由丙烯酰胺单体(AM)及其衍生物聚合形成的均聚物与共聚物统称为聚丙烯酰胺(PAM),聚丙烯酰胺作为水溶性聚合物,在水处理、造纸、石油、煤炭等行业中被广泛的使用。AM-DAC共聚物属于阳离子型聚丙烯酰胺聚合物(CPAM)体系,是一类水溶性线型高分子聚合物,具有正电荷密度高、特性粘度高、水溶性好等优点。现今,对于丙烯酰胺单体的双水相共聚合方法已有研究,但是关于丙烯酰胺单体与阳离子单体共聚反应的研究还很少,它在合成过程中引入了阳离子单体,不但解决了普通水溶液聚合反应过程中传热和搅拌难等系列问题,同时又使反应体系更加稳定,使其更符合工业发展过程中对水溶性聚合物的要求。本论文以丙烯酰胺(AM)单体与丙烯酰氧乙基三甲基氯化铵DAC(阳离子单体)为聚合反应单体,聚乙二醇为(PEG)分相介质,选择氧化还原体系过硫酸铵—亚硫酸氢钠为引发剂,通过双水相共聚法合成所需产物阳离子型聚丙烯酰胺P(AM-DAC)共聚物。同时对聚合产物的相对分子质量及阳离子度进行考察,通过红外光谱图进行表征,并将产物应用于模拟废水,以去除率为比较值,对产物的絮凝能力进行测定。通过单因素实验考察引发剂、单体浓度、温度、单体比以及分相介质浓度等条件对共聚物合成体系的共聚物分子量及阳离子度的影响,同时通过设计正交实验(四因素三水平),通过实验得到合成高分子量的共聚物的优化反应条件为:引发剂0.2 mL,温度40℃,单体总量16%,PEG 3.5 g;该条件下聚合物相对分子质量为11.24×105。阳离子度的优化反应条件为:引发剂0.2 mL,温度50℃,单体总量12%,PEG 3.0 g,在此条件下合成的聚合产品阳离子型聚丙烯酰胺阳离子度为28.67%。同时,通过对聚合产物进行红外光谱表征,对其聚合分子结构进行分析,结果显示聚合产物CPAM确实是由AM与DAC两种单体聚合而成的。分别采用Fineman-Ross(F-R)法、Kelen-Tudos(K-T)法和Yezrielev-BrokhinaRoskin(Y-B-R)法三种方法对AM与DAC的竞聚率进行测定,结果表明通过K-T法和Y-B-R法测定的竞聚率值比较接近且相对准确,两种单体的竞聚率分别为:rAM=2.1800,rDAC=0.28966,两种单体共聚属于非理想共聚。并通过计算得到的竞聚率值分析共聚物的序列长度分布,同时绘制共聚体系组成曲线。将自制的P(AM-DAC)聚合产品用于模拟废水硅藻土悬浊液的絮凝处理,将去浊率作为衡量自制产品絮凝效果的指标,研究了不同相对分子质量及阳离子度对絮凝效果的影响,并从中选取絮凝效果较好的一组产品作为最终产品,经过分别考察自制产品投加量、pH值、絮凝时间、转速大小及沉淀时间等因素对硅藻土悬浊液絮凝性能的影响以及正交实验的分析,结果表明最佳工艺条件为絮凝剂用量5 mL,转速240 r/min,pH 6,搅拌时间15 min。同时,在该条件下CPAM对高岭土悬浊液的去除率达到87.5%。
[Abstract]:The homopolymers and copolymers formed by polymerization of acrylamide monomers and their derivatives are collectively called polyacrylamide (PAM), polyacrylamide (PAM) as water-soluble polymers, in water treatment, papermaking, petroleum, AM-DAC copolymers are widely used in coal industry and belong to cationic polyacrylamide polymer (CPAM) system. They are a kind of water-soluble linear polymer with high positive charge density, high intrinsic viscosity and good water solubility. However, the copolymerization of acrylamide monomers with cationic monomers has not been studied, and cationic monomers have been introduced in the synthesis process. It not only solves a series of problems such as difficult heat transfer and agitation in the polymerization of ordinary aqueous solution, but also makes the reaction system more stable, making it more suitable for the requirements of water-soluble polymers in the industrial development process. In this paper, acrylamide amylase monomer and acryloxyethyl trimethylammonium chloride (DAC) were used as polymerization monomer and polyethylene glycol as phase separation medium. The redox system was composed of ammonium persulfate and sodium bisulfite as initiator. The Cationic polyacrylamide (PAM) AM-DAC copolymers were synthesized by aqueous phase copolymerization. At the same time, the relative molecular weight and cationic degree of the polymerized product were investigated, and the flocculation ability of the product was measured by infrared spectroscopy. The product was applied to the simulated wastewater and the removal rate was taken as the comparative value. The effects of initiator, monomer concentration, temperature, monomer ratio and concentration of phase separation medium on the molecular weight and cationic degree of copolymers were investigated. At the same time, by designing orthogonal experiment (four factors and three levels), the optimum reaction conditions of synthesized high molecular weight copolymers were obtained as follows: initiator 0.2 mL, temperature 40 鈩，

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