我国聚丙烯酰胺的产业化现状与发展建议

综述了我国聚丙烯酰胺行业的产业化进展和市场情况,汇总分析了近年来国内聚丙烯酰胺行业的消费结构和供需关系等。指出我国聚丙烯酰胺行业消费量将保持稳定的增长趋势;用于水处理和污水治理领域的应用将快速增长,向全球消费结构靠拢;今后应加大阳离子型聚丙烯酰胺的研究力度,加快行业技术改造及升级。     

聚丙烯酰胺的生产技术与市场分析

我国微生物法聚丙烯酰胺生产技术水平和产量居国际前列.判断该法迟早会取代其他化学法.国内市场的阴离子型聚丙烯酰胺供销两旺,仍是今后市场主力;阳离子型聚丙烯酰胺的国内产品只能在低端竞争,预计未来几年将进入黄金发展期.     

水质变化对煤泥水絮凝沉降的影响

以高浓度难沉降煤泥水为研究对象,进行了水的pH、硬度对不同类型絮凝剂沉降澄清效果的影响研究。结果表明：非离子型聚丙烯酰胺在煤泥水pH为9,阳离子型聚丙烯酰胺和阴离子型聚丙烯酰胺在pH为5左右时絮凝沉降效果较好;非离子型聚丙烯酰胺、阳离子型聚丙烯酰胺、阴离子型聚丙烯酰胺在水质硬度分别为17.8,53.4,71.2 mmol/L时絮凝沉降效果较好。     

聚丙烯酰胺新产品的合成

聚丙烯酰胺是由丙烯酰胺聚合而成的水溶性的溶液,有粉末状、溶液及胶体等多种类型。对聚丙烯酰胺的合成技术进行研究,优化生产加工技术措施,获得更多的新产品,使其满足市场的需要。     

纳米二氧化锰催化降解聚丙烯酰胺工艺条件研究

聚合物驱油技术在提高原油产量的同时,产生了大量含聚丙烯酰胺的废水,因此需要开发有效降解聚丙烯酰胺的工艺,降低污水中聚合物的浓度。通过水热法制备了纳米二氧化锰催化剂,并对该催化剂进行了评价,采用扫描电镜对其进行了表征。讨论了聚丙烯酰胺的相对黏度,对聚丙烯酰胺降解工艺条件进行了优化,考察了催化剂加入量、降解时间及降解温度对聚丙烯酰胺降解率的影响。结果表明:催化剂质量分数为1%、降解时间4 h及降解温度40℃时,聚丙烯酰胺降解率高达93.95%;自制纳米二氧化锰催化剂为均匀的棒状纳米晶,结晶度好,分散性好。     

不同类型聚丙烯酰胺的制备方法研究进展

聚丙烯酰胺是水溶性高分子聚合物,按离子类型分为阳离子型聚丙烯酰胺、阴离子型聚丙烯酰胺和两性离子型聚丙烯酰胺三种。本文对不同类型聚丙烯酰胺的性质和特点作了概述,对其制备方法进行了总结,对今后进一步研究提出了建议。     

聚丙烯酰胺水溶液管道流动特性研究

采用可控温不锈钢环道对集输管道常见浓度范围内含聚丙烯酰胺水溶液的流动特性进行了室内实验研究。研究结果表明:温度对聚丙烯酰胺溶液压降梯度的影响存在一个临界浓度,在临界浓度后,聚丙烯酰胺溶液的压降梯度随温度的升高逐渐减小,在临界浓度前会出现随温度升高压降梯度增大的现象;压降梯度随聚丙烯酰胺浓度的升高先减小后增大,随流速的降低、温度的升高聚丙烯酰胺溶液的最低压降点后移。减阻率随流速的升高逐渐增大;随流速的降低、温度的升高最高减阻率点后移。聚丙烯酰胺溶液表现出明显的剪切稀释性。通过对实验数据的分析得到了聚丙烯酰胺溶液的增黏特性占主要地位时其混合黏度符合的方程组。     

二氧化氯对聚丙烯酰胺降解作用的实验研究

随着三次采油技术的不断发展,油井堵塞问题越来越严重。主要研究了不同浓度的二氧化氯对聚丙烯酰胺的降解作用,以及温度对其影响,并对二氧化氯降解聚丙烯酰胺的机理进行了探讨。主要测定在6 h内,随着时间的变化,不同温度及不同二氧化氯浓度下聚丙烯酰胺的黏度,以此来判定二氧化氯对聚丙烯酰胺的降解效果。结果表明：在室温下,降解2%（质量分数）的聚丙烯酰胺溶液的最佳二氧化氯质量分数为4×10^-3;当二氧化氯质量分数为4×10^-3时,降解2%（质量分数）的聚丙烯酰胺溶液的最佳温度为60 ℃。     

聚丙烯酰胺的技术及市场分析

综述了聚丙烯酰胺的应用开发及合成技术进展;介绍了国内外聚丙烯酰胺的生产及消费;分析了聚丙烯酰胺的市场前景。     

膨润土/聚丙烯酰胺复合吸水保水材料的制备及性能研究

以膨润土、聚丙烯酰胺为原料,采用溶液共混法制备膨润土/聚丙烯酰胺复合吸水保水材料.借助XRD、SEM、Fr-IR、TG-DSC对制备的样品进行了表征分析.试验表明:膨润土与聚丙烯酰胺用量质量比为8∶2时,制备的材料吸水、吸盐和保水性能均良好,适合作为固沙材料的保水添加剂;聚丙烯酰胺改性膨润土,没有改变膨润土的骨架结构,只是聚丙烯酰胺插层进入膨润土层间,增大了膨润土的晶面间距,以及改变表面粗糙程度;改性膨润土的热稳定性高于原膨润土.     

合成高分子聚丙烯酰胺参数的确定

通过分析合成高分子聚丙烯酰胺（PAM）的影响因素，确定了最佳工艺条件：引发剂过硫酸铵加入量为AM的0.1%-1%,AM单体浓度为10％－12％，EDTA加入量为AM的0．1％作为络合剂，用氮气控制聚合环境，聚合温度在40－70℃，反应时间2－4h，可得到分子量超过10^7、水解度在20％－30％可调的速溶高分子量PAM。     

聚乙二醇／聚丙烯酰胺共混物的制备及性能研究

通过微波加热法制备聚丙烯酰胺,将其与聚乙二醇共混制备聚乙二醇／聚丙烯酰胺（PEG,PAM）共混物,采用傅立叶变换红外线光谱（FTIR）,差示扫描量热仪（DSC）,X射线粉末衍射仪（XRD）,熔点偏光显微镜等测定共混物的性能。结果显示共混物中PEG与PAM形成氢键,共混物的升降温过程中具有吸热和放热峰,相变温度和相变焓随共混物中PAM含量的增加,逐渐降低。PAM的存在对PEG的结晶过程造成了破坏,共混使PEG难以形成均匀球晶,结晶粒子变大。     

EPDM基吸水膨胀橡胶的力学性能

研究了三元乙丙橡胶与聚丙烯酰胺共混制得的吸水膨胀橡胶的力学性能,发现聚丙烯酰胺用量对干态吸水膨胀橡胶的强伸性能有明显影响;而当聚丙烯酰胺含量一定时,随吸水膨胀橡胶率的提高 ,强伸性能出现一个最佳值后下降,压缩永久变形则随吸水膨胀率的提高而减小,这现现象可能与聚丙烷酰胺吸水后物理性质变化有关。     

Dynamic mechanical properties of paper containing a polyacrylamide dry‐strength resin additive and its distribution within a fiber wall: Effect of the application method

Laboratory handsheets made from lightly beaten hardwood kraft pulp containing various amounts of cationic‐type polyacrylamide (PAM) dry‐strength resin were prepared by both internal and external application methods. We performed the internal application by adding a dilute aqueous PAM solution to a pulp fiber suspension, whereas we performed the external application by dipping a dry paper (handsheet) into an aqueous PAM solution and further squeezing it out with or without the standard wet press. Attenuated total reflection/Fourier transform infrared analysis combined with a gradual etching method was used to clarify the difference in the depth profiles of PAM within a fiber wall between these application methods. For the internal application method, PAM existed, on the whole, mainly close to the fiber surface and slightly distributed from the fiber surface toward the center of the fiber wall. On the other hand, for the external application method, PAM existed mainly on the fiber surface and around the fiber‐to‐fiber bonds. Dynamic mechanical properties of the papers containing PAM were measured at temperatures ranging from 100 to 300°C and at the various frequencies. In case of addition by the internal method, no characteristic viscoelasticity of PAM appeared. On the other hand, external method addition at the nearly same retention level of PAM gave the characteristic viscoelasticity. These findings suggest following things: when cationic‐type PAM dry‐strength resin was applied by the internal method, the PAM distributes within the fiber wall in a molecularly dispersed state. The induced state of PAM within the fiber wall, with no existence of a phase of PAM, led to the disappearance of the viscoelasticity of the PAM. On the other hand, the external application method brought about the PAM distribution around the fiber‐to‐fiber bonds and over the fiber surface. The induced state of PAM, the existence of a kind of PAM phase, led to the appearance of the viscoelasticity of the PAM itself. Dynamic mechanical analysis may be a good method for examining whether PAM is molecularly distributed or making aggregates in paper and other polymer composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

聚丙烯酰胺应用于饮用水处理研究

聚丙烯酰胺是有机高分子在水处理方面应用最广泛的絮凝剂,它能够提高絮凝效果,克服枯水期絮体上浮;节约矾耗,降低净水成本;提高水质,去除色度;去除有机物和藻类,降低致突变性。在控制聚丙烯酰胺的质量和用量前提下,用于饮用水处理是安全的,处理后的饮用水符合大多数国家的标准。在国外,水处理是聚丙烯酰胺最大的消费市场,占其总消费量的67％;我国聚丙烯酰胺的主要消费领域是石油开采,水处理占第二位,为总消费量的5％。我国应用聚丙烯酰胺类有机产品作水处理剂,将会随着水质性缺水范围的增大和国民对饮用水要求的提高而逐步扩大。     

膨润土结合PAM处理含镍废水的研究

对膨润土的用量、吸附时间、pH值等因素对去除镍离子效果的影响做了实验 ,找出了影响规律 ,初步探讨了其作用机理。并在此试验的基础上 ,选取pH值、膨润土的用量、PAM的用量三个因素做了三因素三水平的正交试验 ,找出了膨润土结合PAM处理含镍废水的最佳工艺为 pH 8.5 ,膨润土添加量 5 .0 g/L ,PAM用量 1.0mg/L     

Pitch-based carbon foam electrodeposited with lead as positive current collectors for lead acid batteries

Lead electrodeposited carbon foam (LCF), whose substrate was made from pitch by a template method, was investigated as possible positive current collectors for lead acid batteries. Scanning electron microscopy, cyclic voltammetry, and galvanostatic charge–discharge tests were employed to characterize the effect of the proposed collector on the structure and electrochemical properties of the positive active material (PAM). The LCF with uniform and dense lead coating shows the similar electrochemical characteristics to metallic lead in the voltage range where the positive electrodes of lead acid batteries operate. The LCF and lead slices were used as the positive current collectors to equip lead acid batteries, respectively. Comparative charge–discharge tests show that a battery equipped with a LCF collector exhibits higher PAM utilization efficiency and longer cycle life, for LCF can provide large specific surface area which is beneficial to electrochemical reactions and PAM adhesion. In addition, a light lead acid battery with a LCF positive current collector and a carbon foam negative current collector was made and tested for the first time. It deserves systematic industrial study in the future.     

Influence of flocculant polyacrylamide on concentration of titanium white waste acid by direct contact membrane distillation

Effort has been made to investigate the concentration of titanium white waste acid (TWWA) by direct contact membrane distillation (DCMD) and the focus is the influence of polyacrylamide (PAM) on membrane wetting and fouling. It was found that the presence of PAM in feed reduced membrane flux and retarded wetting development, even though its level in feed of H₂SO₄ solution was only 0.0002 wt%. The difference between the tests using pure water and neat PAM aqueous solution, respectively, as feed also indicated the above effect registered with PAM. AFM results showed that the addition of PAM in feed solution changed the membrane shell surface morphology. However, conclusive proof of the PAM existence in membrane cross-section and inner surface was not obtained, probably due to its low concentration in feed solution. Two approaches were tried to recover membrane flux. In comparison with operation w/o any treatment, HCl solution rinsing did not lead to obvious improvement in membrane flux recovery, while rinsing combined with gas purge has clearly delayed the degradation in acid concentration factor. Nevertheless, even the latter could not ensure long term stability. High tortuosity and low hydrophobicity of the membranes used were suggested as underlying causes and should be addressed in the future.     

Influence of flocculant polyacrylamide on concentration of titanium white waste acid by direct contact membrane distillation

Effort has been made to investigate the concentration of titanium white waste acid (TWWA) by direct contact membrane distillation (DCMD) and the focus is the influence of polyacrylamide (PAM) on membrane wetting and fouling. It was found that the presence of PAM in feed reduced membrane flux and retarded wetting development, even though its level in feed of H₂SO₄ solution was only 0.0002 wt%. The difference between the tests using pure water and neat PAM aqueous solution, respectively, as feed also indicated the above effect registered with PAM. AFM results showed that the addition of PAM in feed solution changed the membrane shell surface morphology. However, conclusive proof of the PAM existence in membrane cross-section and inner surface was not obtained, probably due to its low concentration in feed solution. Two approaches were tried to recover membrane flux. In comparison with operation w/o any treatment, HCl solution rinsing did not lead to obvious improvement in membrane flux recovery, while rinsing combined with gas purge has clearly delayed the degradation in acid concentration factor. Nevertheless, even the latter could not ensure long term stability. High tortuosity and low hydrophobicity of the membranes used were suggested as underlying causes and should be addressed in the future.     

Effect of silica and poly(ethylene glycol) on the in vitro release rate of 2‐pyridine aldoxime chloride from polysiloxane matrices

The release rate of 2‐pyridine aldoxime chloride (PAM‐Cl) from polysiloxane matrices was found to be in the order poly(vinylmethyldiethylsiloxane) (P(VM‐DE)S) > poly(dimethyldiethyl siloxane) P(DM‐DE)S > poly(vinylmethylsiloxane) (PVMS) > poly(dimethylvinylmethylsiloxane) (P(DM‐VM)S) > poly(dimethylsiloxane) (PDMS). The time for 80% PAM‐Cl release from polysiloxane matrices was found to be in the range 5–14 h. Incorporation of silica (5–10%) as a filler in these matrices reduced the release of PAM‐Cl and in some cases stopped drug release completely. However, the incorporation of crosslinked poly(ethylene glycol) (PEG) (5–20%) in polysiloxane matrices increased the release rate and reduced the time for 80% drug release. Slow release formulations were made by incorporating 5% silica and 5–20% PEG in PDMS, keeping the PAM‐Cl and PEG ratio 1:1. The formulations PDMS + 5% silica + 5–20% PEG + 5–20% PAM‐Cl gave a slow release of PAM‐Cl and the time for 80% drug release was found to be 12 h in each case at pH 7.4 and 37 °C. PVMS and siloxane copolymers showed times for 80% drug release of 6–10 h in comparison with 12 h for PDMS. Diffusion coefficient values for PAM‐Cl–PDMS system are also calculated. © 2000 Society of Chemical Industry