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本文采用由氧化还原体系、偶氮化合物和辅助引发剂组成的复合引发体系,通过水溶液自由基共聚合,引发丙烯酰胺与阳离子单体反应得到阳离子聚丙烯酰胺,该产品可用于水处理絮凝剂。阳离子聚丙烯酰胺相对分子质量最高可达2.276×107,阳离子单体质量分数可在1%~100%范围内任意调控。考察了pH值,引发剂浓度、单体质量分数、引发温度和辅助引发剂等添加剂用量对聚合反应的影响。通过正交实验,确定了优化工艺参数;引发剂浓度,6×10-3%(对单体);单体质量分数,20%;pH值,8;引发温度,10℃;四甲基乙二胺浓度,6×10-2%;偶氮二异丁腈浓度,8×10-3%。 相似文献
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将过硫酸铵-亚硫酸氢钠与2,2'-偶氮(2-脒基丙烷)二氢氯化物(V-50)组成的复合引发体系用于丙烯酰胺(AM)与丙烯酰氧乙基三甲基氯化铵(DAC)聚合,制备了高分子质量的阳离子聚丙烯酰胺P(DAC-AM).探讨了单体质量分数、引发剂用量、阳离子单体含量、pH、反应时间等因素对聚合物特性黏数的影响.得到的最佳反应条件为:单体最佳质量分数为35%,引发剂用量为整个体系质量的0.02%,V-50为单体质量的0.005%,最佳pH为5.5~6.5,尿素为单体质量的0.1%,EDTA为单体质量的0.02%,β-二甲胺基丙腈为单体质量的0.03%,反应时间为5~6h.特性黏数η达到13.95 dL/g. 相似文献
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以丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为单体原料,采用(NH4)-2S208/NaHSO3和偶氮类化合物组成的复合引发体系,通过自由基水溶液聚合法合成阳离子聚丙烯酰胺P(DMC-AM).正交试验评价得出较佳的工艺条件是:AM/DMC质量配比为4∶3,单体浓度为35%,复合引发剂浓度为0.014%,pH值为4,反应温度为30℃.在上述条件下,产物的特性粘数为8.632dL g-1,阳离子度为20.09%;用红外光谱技术对产物结构进行了表征;在其加入量为8mg L-1的条件下处理硅藻土悬浮液,上层清液透光率接近100%;比较了P(DMC-AM)、无水AlCl3和二者联合处理生活污水的不同絮凝效果,实验表明:P(DMC-AM)的絮凝效果优于无水AlCl3絮凝剂,而二者联合处理的絮凝效果更佳. 相似文献
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采用氧化还原剂和偶氮类化合物组成的复合引发体系,通过水溶液聚合法制备丙烯酰胺(AM)和甲基丙烯酰氧乙基三甲基氯化铵(DMC)的共聚物。研究了氧化还原剂总质量分数、氧化剂与还原剂的质量比、偶氮类化合物的种类和质量分数、引发温度、pH值、单体质量分数等对产物特性粘数的影响。得到的较佳工艺条件:氧化还原剂总质量分数0.015%、氧化剂与还原剂质量比0.7、偶氮类化合物质量分数0.012 5%、引发温度25℃、pH值6.0、单体质量分数45%,在上述条件下,产物特性粘数为12.370 8 dL/g。用红外光谱技术对产物的结构进行表征。 相似文献
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阳离子聚丙烯酰胺“水包水”乳液的制备研究 总被引:2,自引:0,他引:2
在硫酸铵溶液中,以相对分子质量为7.44×10~5~1.21×10~6的聚甲基丙烯酰氧乙基三甲基氯化铵为分散剂,在偶氮二异丁脒盐酸盐引发剂的作用下,通过分散聚合进行了丙烯酰胺和甲基丙烯酰氧乙基三甲基氯化铵的二元共聚。分别探讨了分散剂浓度、无机盐浓度、单体总浓度及其配比、引发剂浓度、反应温度等对分散聚合的影响,找出了各影响因素之间的协同规律,最终确定出最佳的合成条件和体系配比。在上述条件下制备出颗粒分散性较好、流动性较好、稳定性较高、特性黏数及黏均分子量较高的阳离子聚丙烯酰胺"水包水"乳液。 相似文献
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新型超高相对分子量阳离子聚丙烯酰胺的合成 总被引:8,自引:0,他引:8
研究了由过硫酸铵、甲醛次硫酸氢钠、功能性单体 DA及其它助剂组成的低温复合引发体系引发丙烯酰氧乙基三甲基氯化铵 (AETMAC)与丙烯酰胺 (AM)水溶液绝热聚合。考察了影响共聚物特性黏数[η]的因素 :单体浓度 1 8%~ 3 2 % ,引发剂浓度 (9~ 3 0 ) mg/L ,功能单体浓度 (2 .9~ 2 3 .2 )× 1 0 - 3mol/L。由该低温复合引发体系在适宜条件下引发 AETMAC/AM共聚合 ,可得到溶解性能很好、阳离子度为 1 0 %~70 % ,分子量 (1~ 2 )× 1 0 7的 P(AETMAC-AM)干粉。 相似文献
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采用氧化一还原引发体系,以丙烯酞胺、丙烯酸为单体,通过水溶液聚合合成了高分子量的阴离子型聚丙烯酞胺.研究了EDTA用量、反应时间、pH值和AA/AM配比等对聚丙烯酞胺分子量、聚合转化率以及溶解性能的影响. 相似文献
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Aqueous two‐phase copolymerization of acrylamide(AM) and acryloyloxyethyl trimethyl ammonium chloride (DAC) was performed in poly(ethylene glycol) (PEG) solution and in PEG chloride(Cl‐PEG) solution, respectively. Series of cationic polyacrylamide(CPAM) aqueous dispersion were prepared using potassium persulfate (KPS) as initiator. The effect of total amount of monomers, the dosage of initiator, the content of dispersant, the mass ratio of AM to DAC, and the temperature on the conversion, molecular weight, cationic degree, and stability of aqueous dispersion were studied in detail. It is found that the increase of initiator and reaction temperature resulted in the increase of the final conversion, whereas the increase of DAC and PEG concentration resulted in the decrease of the final conversion. The optimum reaction conditions of synthesis were as follows: (1) PEG‐H2O system: PEG 7.5 g, AM 8 g, DAC 2 g, KPS 0.05 g, H2O 100 mL, 70°C. In this process conditions, the molecular weight of CPAM was 3.21 × 106, the cationic degree of CPAM was 24.4%, the storage stability of the aqueous dispersion was over 3 months. (2) Cl‐PEG‐H2O system: Cl‐PEG 7.5 g, AM 8 g, DAC 2 g, KPS 0.05 g, H2O 100 mL, 65°C. In this process conditions, the molecular weight was 3.68 × 106, the cationic degree was 23.3%, and the storage stability of the aqueous dispersion was over 6 months. In general, the stability of CPAM aqueous dispersion in Cl‐PEG system is much better than in PEG system. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Equivalent electrical conductivity (Λ) is reported for three series of cationic quaternary ammonium polyacrylamide derivatives with $\hbox{MeSO}_{4}ˆ{‐}$ , Cl−, Br− and I− as counterions at 25 °C, the polyion equivalent concentration C ranging from 5.3 × 10−4 to 6.4 × 10−3 N and from 1.0 × 10−3 to 1.4 × 10−2 N. Equivalent electrical conductivity increases with decreasing polyion equivalent concentration, and the sequence of equivalent electrical conductivity Λ of polyelectrolytes for the same series with different counterions in the range of concentration investigated is: $\hbox{MeSO}_{4}ˆ{‐} > \hbox{Cl}ˆ{‐} > \hbox{Br}ˆ{‐} > \hbox{I}ˆ{‐}$ . The plots of the counterion–polyion interaction parameter f and degree of dissociation α of polyelectrolyte versus the polyion equivalent concentration C show that the order of counterion associating or binding to polyions for the same polyelectrolyte series in the range of concentration studied is $\hbox{MeSO}_{4}ˆ{‐} < \hbox{Cl}ˆ{‐} < \hbox{Br}ˆ{‐} < \hbox{I}ˆ{‐}$ . The chemical structures of the polyion have much influence on the Λ, f and α values of the polyelectrolytes. © 1999 Society of Chemical Industry 相似文献
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浓乳液聚合产品稳定性好,颗粒尺寸更接近地层孔隙尺寸,在油田开发中具有较大的应用价值。基于微乳液制备了一系列甲基丙烯酰氧乙基三甲基氯化铵和丙烯酰胺的浓乳液,通过电导率测试、流变性分析、显微镜观察,研究了聚合前后浓乳液结构、粒径分布及稳定性。结果表明浓乳液的黏度及屈服应力,随着水相单体浓度(CM)增加而降低,随着油相中表面活性剂含量(mS)增加先升高后降低,乳液稳定性有相同趋势;浓乳液在CM>40%及mS=2.5 g时的失稳,原因分别是渗滤作用和高黏度下乳化不充分;聚合前液滴粒径分布在1~30 mm,聚合后微球粒径在0.4~5 mm,且粒径分布由聚合前双峰变为聚合后单峰,这一现象可以由Kolmogoro-Hinze的乳化理论解释,并由微球乳液的黏度增加至原始浓乳液的10倍证实。 相似文献
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Copolymer particles consisting of acrylamide (AM) and acryloyloxyethyl dimethylbenzyl ammonium chloride (AODBAC) were prepared by dispersion polymerization in an aqueous solution of ammonium sulfate and in the presence of poly(acryloyloxyethyl trimethyl ammonium chloride) (PAOTAC) as the stabilizer. The average particle size ranged from 4 to 7 μm, and Mw and Mn were 2–6 ×106 g/mol and 1–3 × 106 g/mol, respectively. The effects of the AM/AODBAC ratio, monomer, initiator, salt, and stabilizer concentration on the particle size and molecular weight were studied. Increase of the AODBAC/AM ratio resulted in a decrease in the molecular weight and an increase in particle size. With the increase of the AODABA/AM ratio, the dispersion became less stable during long storage. Due to the presence of the salt, ionization of the quaternary ammonium groups in the dispersed particles is considered significantly suppressed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1101–1108, 2003 相似文献
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水溶液聚合法制备聚丙烯酸盐型高吸水聚合物 总被引:9,自引:0,他引:9
以丙烯酸和丙烯酰胺为混合单体,过硫酸铵为引发剂,N,N'-亚甲基双丙烯酰胺为交联剂,开发了一种采用水溶液聚合法制备聚丙烯酸盐型高吸水聚合物的技术。其特点是采用高浓度的混合单体体系,于盘式反应器中进行聚合和交联反应,利用反应放出的热量脱除体系中的水分,无需额外的干燥工序。所得产物吸水率为400 ̄700g/g。 相似文献
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《应用化工》2017,(8):1521-1525
采用反相乳液聚合法,以丙烯酰胺(AM)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)、N-乙烯基-2-吡咯烷酮(NVP)为单体,煤油为油相,司班-80和吐温-60为乳化剂,过硫酸钾和亚硫酸氢钠为引发剂制备共聚物。考察单体质量比、引发剂用量、反应温度、乳化剂用量、油水比对共聚物特性粘数的影响。红外光谱仪表征共聚物结构,Brookfield粘度计测定聚合物耐温性和抗盐性。结果表明,当单体质量比AM∶AMPS∶NVP为1∶0.2∶0.025,引发剂总用量为单体总重量的2%,反应温度为40℃,乳化剂总浓度为0.1 g/mL,油水比为1∶1时,共聚物特性粘数最大为936 mL/g,且有较好的耐温抗盐性。 相似文献