疏水缔合型阳离子聚丙烯酰胺的溶液性能与应用研究

以丙烯酰胺(AM)、二甲基二烯丙基氯化铵(DMDAAC)、丙烯酸十八酯(OA)为单体,用氧化-还原引发体系,通过自由基胶束共聚法制得疏水缔合型阳离子共聚物PADO。研究了共聚物组成对PADO溶液性能的影响,以及PADO对造纸中段废水的絮凝效果。结果表明,PADO水溶液中存在强烈的分子间缔合作用,在处理造纸中段废水时,其应用效果优于聚合硫酸铁、聚合氯化铝和非离子PAM。     

疏水缔合型阳离子聚丙烯酰胺研究

以甲基丙烯酰氧乙基三甲基氯化铵(DMC)作为阳离子单体,以丙烯酸甲酯作为疏水单体(MA),以丙烯酰胺(AM)为共聚单体,以亚硫酸氢钠和过硫酸铵为常温复合引发剂,以过硫酸铵为高温引发剂,通过溶液聚合制备疏水缔合型阳离子聚丙烯酰胺.通过红外光谱检测分析其结构,结果表明在两种引发体系下生成的聚合物都为AM、DMC和MA的三元...     

疏水改性阳离子聚丙烯酰胺絮凝剂的制备及絮凝性能测试

以获得疏水作用力为目标,使用丙烯酸丁酯(BA)对阳离子聚丙烯酰胺(PAM)进行改性,采用自由基胶束聚合法合成P(AM-DAC-BA)三元共聚物,以红外光谱进行结构表征,并考查了制备工艺条件对絮凝性能的影响.结果显示:疏水改性阳离子絮凝剂对高浊度污水具有更好的絮凝效果,疏水单体含量、阳离子含量均对絮凝效果影响较大;疏水单体配比为3 mol％,阳离子单体配比为20～25 mol％,絮凝剂用量为10.0 mg/L;污水pH值为8时,对30 wt％高岭土浊水的絮凝沉降率可达96.5％.     

疏水缔合改性丙烯酰胺共聚物的合成

采用自由基胶束聚合法合成了丙烯酰胺（AM）/丁基苯乙烯（BS）/2-甲基-2-丙烯酰胺基丙磺酸钠（NaAMPS）疏水缔合水溶性共聚物PASA,PASA避免了目前疏水缔合聚合物溶液热稳定性差的问题.研究得到了适宜的反应条件,包括NaAMPS、BS和引发剂加量相对于单体总量的摩尔分数分别为10%、2.5%和0.07%,总单体在水里的质量分数为10%,SDS在水里的质量分数为6.0%,反应温度50℃,pH=6～7,反应时间12 h.采用以上反应条件得到PASA的临界缔合质量浓度为0.05 g·dL^-1,对应的水溶液表观黏度为283 mPa·s,质量浓度为0.1 g·dL^-1的水溶液表观黏度为1020 mPa·s.采用元素分析、UV、FT-IR和¹HNMR证实了共聚物的分子结构;DSC分析表明了共聚物分子链中存在疏水嵌段.     

丙烯酰胺/丁基苯乙烯疏水缔合共聚物的合成与表征

以丁基苯乙烯(BS)为疏水单体,采用自由基胶束聚合法合成了丙烯酰胺(AM)/丁基苯乙烯(BS)疏水缔合水溶性共聚物(PSAM),来解决该类聚合物热稳定性较差的难题。研究得到了适宜的反应条件:n(K2S2O8)∶n(Na2SO3)=3∶1,引发剂和BS相对于单体总量的摩尔分数分别为0.06%和1.45%,总单体在水里的质量分数为20%,SDS在水里的质量分数为5.5%,pH=6~7,反应温度50℃。采用该反应条件得到PSAM的临界缔合质量浓度为1 g/L,对应的水溶液表观黏度为21 mPa.s;质量浓度为2 g/L时,对应的水溶液表观黏度为78 mPa.s;质量浓度为1 g/L和2 g/L的PSAM在浓度为0.137 mol/L的NaC l水溶液中,于80℃老化120 d后的表观黏度分别为11.8 mPa.s和49.3 mPa.s,黏度保留率分别为42.1%和45.1%。通过元素分析、UV、FTIR表征了PSAM的分子结构;DSC分析表明PSAM为嵌段共聚物,两个玻璃化转变温度分别为BS链段的106℃和丙烯酰胺链段的203℃。     

疏水改性聚丙烯酰胺的胶束聚合法制备及表征研究进展

综述了近年来HMPAM的胶束聚合法的研究进展,介绍了胶束聚合法的原理和合成条件,包括单体、表面活性剂、引发剂、聚合温度和聚合时间以及HMPAM的相对分子质量及组成的表征方法。     

阳离子聚丙烯酰胺反相胶乳的制备及其絮凝性能

以丙烯酰胺和甲基丙烯酰氧乙基三甲基氯化铵为单体,通过反相乳液聚合法制备了絮凝性能优异的阳离子聚丙烯酰胺反相胶乳。考察了乳化剂浓度、引发剂浓度、单体浓度及阳离子度对聚合物分子量和粒子粒径的影响,并研究了污泥pH值、污泥温度和聚合物用量等条件对絮凝性能的影响。得到的较佳条件是:乳化剂质量分数7.3%,引发剂质量分数0.02%、单体质量分数45%、阳离子度25%,在上述较佳条件下所得聚合物的黏均分子量为339.2万,粒子粒径均低于70 nm;污泥pH值为5～6,聚合物用量为0.057%的条件下污泥的絮凝率达62.2%,脱水率达82%。     

疏水缔合型聚丙烯酰胺的研究进展

疏水缔合型聚丙烯酰胺（HAPAM）是疏水缔合水溶性聚合物（HAWSP）中研究最多的一种,它可以通过共聚反应在聚丙烯酰胺中引人少量疏水基团而得到。由于疏水基团的憎水作用,共聚物水溶液中产生分子间缔合作用,从而具有独特的流变性能。在石油开采、污泥处理、涂料工业及生物医学等方面具有良好的应用前景。综述了国内外学者在HAPAM的合成、性质和应用等方面的研究进展,并对其发展前景进行了展望。     

阳离子型聚丙烯酰胺技术条件及絮凝性能评价研究

国家《节能减排"十二五"规划》中,在加强城镇生活污水处理设施建设方面,要求到2015年我国城市污水处理率和污泥无害化处置率分别达到85%和70%。阳离子型聚丙烯酰胺作为一种性能良好的污水处理与污泥脱水剂,被广泛应用于污水处理、污泥脱水处理中。阳离子型聚丙烯酰胺具有优良的选择性和适应性,目前世界有五大系列2 000多个品种,世界年总需求量为65万t,年需求增长率为10%。今后我国污泥脱水处理、污水处理、石油开采、造纸等领域对阳离子聚丙烯酰胺的需求量将不断增长。针对阳离子型聚丙烯酰胺制定了系列质量评价方法并对其在水处理应用方面进行了研究。     

阳离子聚丙烯酰胺对克雷伯杆菌絮凝效果的研究

采用有机絮凝剂阳离子型聚丙烯酰胺对克雷伯菌菌悬液进行絮凝处理。探讨了浓度、pH值、温度、助滤剂对絮凝剂絮凝及过滤性能的影响,并采用光学显微镜和扫描电子显微镜对菌悬液、絮凝剂和絮体3个方面进行了絮凝形态观察。结果表明,絮凝剂浓度为0.08 g/L,pH=7,温度为37℃时絮凝效果最佳。添加助滤剂Al2(SO4)3.18H2O、CaCl2.2H2O后过滤效果有明显的提高,且絮凝颗粒增大,沉降速度加快。     

Solution properties and flocculation of hydrophobically associating cationic fluorinated polyacrylamide

The hydrophobically associating cationic fluorinated polyacrylamide (CFPAM), modified with fluorinated acrylate, 2-(perfluorooctyl)ethyl acrylate (FEA), has been newly synthesized, by free radical micellar copolymerization in aqueous solution. The solution properties of these polymers were investigated in details in this study. In addition, the flocculation of CFPAM was also evaluated. The results showed that there were strong hydrophobic associations in the CFPAM aqueous solution. The addition of NaCl resulted in an increase of solution viscosity, which indicated the good salt-resistant performance of CFPAM. The polymers also exhibited excellent property of temperature and shearing tolerance. Furthermore, the polymer showed high surface activity. At the same time, its flocculation properties were evaluated with kaolin suspensions using a standard jar test. All the results demonstrated the superiority of the cationic fluorinated polyacrylamide as a flocculant.     

疏水改性阳离子型丙烯酰胺共聚物的微结构与絮凝性能

用自由基胶束聚合法合成了丙烯酰胺（AM）/丁基苯乙烯（BS）/二甲基二烯丙基氯化铵（DMDAAC）疏水缔合型高分子絮凝剂PBAD。通过UV、FT-IR表征了共聚物的分子结构,AFM研究表明,由于丁苯基疏水基团强的分子间作用,0.005 g.dL-1 PBAD在水溶液中已形成了缔合体,并随着聚合物浓度的增加,缔合结构的尺寸和数量显著增加。在3%硅藻土溶液中,PBAD絮凝的最佳用量为0.005 g.dL-1,此时的透光率为96.5%,污水中的NaCl浓度能明显影响聚合物的架桥吸附作用,Ca2+和Al3+能增强聚合物的絮凝效果。     

共聚合阳离子聚丙烯酰胺的合成及性能测试

首先合成阳离子单体N—(二甲氨基)甲基丙烯酰胺，然后用共聚合法合成阳离子聚丙烯酰胺。单体合成中探讨了经甲基二甲胺的合成工艺，当n(甲醛)：n(二甲胺)=2：1，反应温度为55℃，反应时间为2h时，羟甲基二甲胺的收率最高；并通过NMR确定了其结构。采用正交实验，研究了共聚合反应中n(丙烯酰胺)：n(阳离子丙烯酰胺)、温度、引发剂用量对聚合反应的影响。研究结果表明，n(丙烯酰胺)：n(阳离子丙烯酰胺)＝10：1，温度为45℃，引发剂质量分数为0．04％时，效果最佳，达到了一定的絮凝效果。     

Synthesis,characterization, rheological behavior,and shear response of hydrophobically modified polyacrylamide and network structure of its microhydrogel

Octylphenol polyoxyethylene acrylate (OP‐10‐AC) was synthesized, and then OP‐10‐AC was copolymerized with acrylamide (AM) to form hydrophobically modified polyacrylamide P(AM/OP‐10‐AC) through micellar copolymerization. OP‐10‐AC content and rheology behavior of P(AM/OP‐10‐AC) were investigated in detail. Especially, under the conditions of different test methods, P(AM/OP‐10‐AC) showed interesting shear responsive behavior. The results of rheology study show that OP‐10‐AC content, polymer solution concentration, salt solution concentration, and different test methods powerfully influenced shear viscosity of aqueous solutions of P(AM/OP‐10‐AC). In addition, according to the dynamic shear experimental results, the critical hydrogel concentration range (CHCR) could be confirmed for aqueous solutions of P(AM/OP‐10‐AC). Above CHCR, these polymer solutions were essentially a kind of microhydrogels, which could explain the effect of concentration and hydrophobe content on their shear viscosity and viscoelasticity from the microstructure's point of view. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

The flocculation of kaolin by cationic polyacrylamides and the effect of cationic surfactant on this process

The flocculation of kaolin suspended in a dilute salt solution was studied as a function of the addition of cationic surfactant and cationic polyacrylamide (CPAM) added separately, consecutively, or simultaneously. Cationic polyacrylamide caused flocculation by bridging when added in low concentrations, but at higher concentrations, charge neutralization became the dominant mechanism and the flocculation rate was highly dependent on the charge density of the polymer. Adsorption of sufficient polymer or surfactant (cetyl pyridinium chloride) prevented immediate adsorption of the other, although surfactant could replace polymer after extended agitation. The adsorption of polymer was greatest when small flocs were formed by charge neutralization or by prolonged shaking. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2382–2389, 2002