复合引发体系制备磺化聚丙烯酰胺及性能评价

采用氧化还原引发剂(过硫酸铵和甲醛合次亚硫酸钠)与水溶性偶氮引发剂(偶氮二异丁脒盐酸盐)复配的复合引发体系引发丙烯酰胺(AM)与2-丙烯酰胺-2-甲基丙磺酸(AMPS)共聚合成磺化聚丙烯酰胺(SPAM),考察了氧化剂与还原剂配比、复合引发剂配比、聚合引发温度、pH值、单体浓度等条件对聚合物溶液表观黏度的影响,同时对其进行了耐温抗盐性能评价。结果显示,与工业上使用的部分水解聚丙烯稀酰胺(HPAM 3 500万)相比,合成的SPAM具有更好的耐温抗盐性能。     

AM_nBS_SSS三元疏水缔合聚合物PAnBS的合成及溶液性能研究

以对正丁基苯乙烯(nBS)、对乙烯基苯磺酸钠(SSS)和丙烯酰胺(AM)为原料,采用自由基胶束聚合法合成了阴离子型三元疏水缔合聚合物PAnBS,用红外光谱法、紫外光谱法以及核磁共振氢谱法对共聚物的结构进行了表征;考察了不同反应条件对共聚物溶液表观黏度的影响,得到了具有较强增黏能力的聚合物合成工艺条件:nBS、SSS和引发剂用量分别为总单体摩尔分数的1.5%、9%和0.1%,总单体和表面活性剂十二烷基硫酸钠(SDS)在溶液中的质量分数分别为25%和6%,反应温度50℃,反应时间10 h。与相对分子质量(简称分子量,下同)1 970万、水解度19.43%的超高分子量部分水解聚丙烯酰胺(HPAM)相比,所得PAnBS在NaCl或CaCl2水溶液中具有更强的增黏能力;PAnBS在淡水或盐水溶液中于80℃下的耐老化性能优于超高分子量HPAM,表现出优良的耐温抗盐性能。     

驱油用磺酸盐型聚丙烯酰胺的合成及性能表征

在水介质中进行了丙烯酰胺(AM)与2-丙烯酰胺基-2-甲基丙磺酸(AMPS)的溶液共聚合,其最佳反应条件为:单体AM浓度10%,AMPS占AM的17.5%(摩尔比),引发剂加量为AM质量的0.05%,反应温度为50℃。考察了共聚物的抗温性能及对不同盐的承受能力,结果表明,磺酸基团的强阴离子性与庞大侧基的位阻效应,赋于磺酸盐型聚丙烯酰胺P(AM/AMPS)优良的耐温与抗盐性能。     

AM/AMPS/SSS三元共聚物的制备及耐温耐盐性能

我国油田已全面进入三次采油阶段,研制适应高温高盐开采环境下的驱油剂受到广泛关注。针对传统聚丙烯酰胺类驱油剂进行了改性,采用水溶液聚合的方法,制备并优化了丙烯酰胺/2-丙烯酰胺基-2-甲基-1-丙烷磺酸/对苯乙烯磺酸钠（AM/AMPS/SSS）三元共聚物,探究了各种反应条件对产物水溶液表观黏度的影响,总结分析了相关规律,得到最优的共聚物制备条件。使用旋转黏度计,对聚合物溶液的表观黏度、耐温耐盐性能进行了研究,最终得到了耐温、耐盐效果明显,热稳定性良好的AM/AMPS/SSS三元共聚物,在目前严峻的原油开采环境中有较好的应用前景。     

Viscosity and retention of sulfonated polyacrylamide polymers at high temperature

The viscosity and retention of several copolymers of acrylamide (AM) with sodium salt of 2‐acrylamido‐2‐methylpropane sulfonic acid (PAMS), and also hydrolyzed polyacrylamide (HPAM) have been studied under aerobic condition with and without the sacrificial agent, isobutyl alcohol (IBA) added at a temperature of 80°C. Parallel experiments have been performed in synthetic seawater (SSW) and 5 wt % NaCl. The viscosity at high temperature has been studied as a function of aging time, shear rate, sulfonation degree, molecular weight, and concentration of IBA. The retention in porous medium for sulfonated polyacrylamide polymers was measured in core floods using outcrop Berea sandstone. For the studied polymer sacrificial agent may protect polymer structure at high temperature. Higher sacrificial agent concentration gives better thermal stability in both 5 wt % NaCl and SSW solvents. Sulfonation degree also has a direct effect on thermal stability, i.e., higher sulfonation degree lead to better thermal stability in terms of viscosity. By increasing temperature, less relative reduction in polymer solution viscosity was observed for the polymer with lower molecular weight. The presence of divalent ions at high temperature leads to strong reduction of HPAM polymer solution viscosity, but the viscosity is better maintained for PAMS copolymer solution at high temperature. The precipitation of HPAM first occurred after 3 months at 80°C and for PAMS copolymer with lowest sulfonation degree precipitation started after 7 months. For the studied polymers the retention was found to be relatively independent of temperature and compared to HPAM a much lower retention is observed for the sulfonated copolymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

N-叔丁基丙烯酰胺、AMPS与丙烯酰胺共聚物及其水溶液特性的研究

高分子量部分水解聚丙烯酰胺（HPAM）分子结构为线性柔性长链构型。在盐溶液中．由于盐离子的存在减弱了基团间的排斥作用．使分子主链卷曲．流体力学体积减小．导致粘度急剧下降。当分子链上有支链结构的侧基时．由于空间位阻效应,使分子的内旋转受到阻碍,分子链的卷曲度受到限制．使得分子链相对更为伸展．刚性相对更强．分子链流体力学尺寸更大．宏观上表现出高分子聚合物的抗盐增粘性越好．从而提高了聚合物的耐温抗盐性能。     

Properties of high‐temperature‐resistant drilling fluids incorporating acrylamide/(acrylic acid)/(2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) terpolymer and aluminum citrate as filtration control agents

A terpolymer of acrylamide (AM), acrylic acid (AA), and 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid (AMPS) was synthesized by a free‐radical solution polymerization technique, characterized by FTIR methods, and applied together with aluminum citrate in oilfield drilling as a high‐temperature‐resistant filtration control agent. Before and after thermal aging for 16 h at 180°C, the combined effect of the terpolymer and aluminum citrate on the Bingham‐type rheological and fluid‐loss properties of the corresponding fresh‐water and salt‐water muds was further investigated. The results showed that before the thermal aging, there was a similar changing trend in the rheological and fluid‐loss properties of the muds with terpolymer concentration, regardless of the presence of aluminum citrate. After the thermal aging, some hydrophilic polycomplexes of AM‐AA‐AMPS terpolymer with aluminum citrate may have been formed and consequently inhibited viscosity loss of the muds, thereby improving the fluid‐loss properties. A possible mechanism is proposed to explain the improvement. J. VINYL ADDIT. TECHNOL, 2010. © 2009 Society of Plastics Engineers     

AMPS对驱油用聚合物材料耐温抗盐性能影响

研究了含有2-丙烯酰胺基-2-甲基丙磺酸(AMPS)及无AMPS的适用于胜利Ⅱ类油藏聚驱的聚合物材料性能。结果表明,AMPS的引入未增加聚合物的疏水性及地层吸附,却明显地提高了聚合物的耐温抗盐性能及热稳定性。含有AMPS的聚合物溶液在高浓度钙离子水溶液中具有更高的表观黏度。     

AM-MA-AMPS三元共聚物的合成及溶液性能研究

以丙烯酰胺 (AM)、丙烯酸甲酯 (MA)和α 丙烯酰胺基 α 甲基丙磺酸 (AMPS)为原料 ,通过水溶液共聚 ,合成了一种新型三元共聚物 (AM -MA -AMPS) ,并对其进行了表征。DSC和TG测试表明该三元共聚物的玻璃化温度为 2 45℃ ,分解温度为 381 8℃ ,均高于聚丙烯酰胺 (PAM)。实验表明 ,质量浓度为 2 0kg m3 的AM -MA -AMPS三元共聚物的水溶液黏度为 2 1 0 6mPa·s ,标准复合盐溶液黏度为 7 36mPa·s ,均较相应的PAM有提高。     

High char‐yielding poly[acrylonitrile‐co‐(itaconic acid)‐co‐(methyl acrylate)]: synthesis and properties

Polyacrylonitrile terpolymers of various compositions consisting of acrylonitrile (AN), itaconic acid (IA) and methyl acrylate (MA) were synthesized by solution polymerization in dimethylsulfoxide. Increase in concentration of either IA or MA retarded the overall polymerization rate and the polymer molecular weight. The system consisting of AN + MA and varying IA concentration was more prone to retardation in comparison with the system composed of AN + IA with variable MA concentration. The retardation factors were quantified. Minor quantities of MA boost the reactivity of IA in the terpolymer system. The terpolymer was richer in MA vis‐à‐vis the feed. The thermal characteristics of the terpolymer were examined as a function of its composition. In contrast to the copolymer of AN and IA requiring 1–1.5 mol% IA, the terpolymer required an IA content of approximately 2.5 mol% for optimum thermal stability. The polymer with 90 mol% AN, 2.5 mol% IA and 7.5 mol% MA exhibited reasonably good char‐forming characteristics and thermal stability. The overall crystallinity and crystallite size of the polymers were found to decrease on incorporation of the comonomers. The ‘aromatization index’ of the copolymer increased with the temperature of pyrolysis through re‐organization of the tetrahydropyridine ladder structure. Copyright © 2005 Society of Chemical Industry     

Statistical and rheological evaluation of the effect of salts in partially hydrolyzed polyacrylamide solutions

Partially hydrolyzed polyacrylamide (PHPA) is the most common anionic copolymer used in Enhanced oil recovery (EOR), but the use of this polymer presents some limitations in the presence of divalent cations. The objective of this work was to evaluate the thermal stability of PHPA in brines containing Na⁺, Mg²⁺, and Ca²⁺ cations (isolated or combined). In this study, the PHPA used at a concentration of 2500 mgL⁻¹ has a MW of 20 × 10⁶ Da. The stability of the polymeric solutions was monitored through rheological analyses for 180 days at 70°C, in the absence of oxygen, using a central composite rotational design. In the absence of dissolved oxygen and cations, the PHPA solution was basically the same as that observed over a period of 30 days. It was observed that Ca⁺² ion had the greatest influence on reducing the viscosity of PHPA in all cases. Polymeric solutions with Total dissolved solids (TDS) greater than 1000 mg L⁻¹ showed complete degradation of the polymer in 180 days. The statistical data corroborate the rheological results, showing that only the main effect of Na⁺ was not statistically significant and that the concentrations of Mg²⁺ and Ca²⁺ presented statistically significant effects in their linear components and quadratic components.     

Inverse emulsion polymerization of triple monomers of acrylamide,maleic anhydride,and styrene to achieve highly hydrophilic–hydrophobic modified polyacrylamide

The purpose of this study was the production of copolymers and terpolymers with highly hydrophilic–hydrophobic properties, using inexpensive and available monomers as potential enhancing oil recovery (EOR) and water production control agents for high-temperature and high-salinity (HTHS) oil reservoirs. For this purpose, several copolymers and terpolymers with different molar percentage of acrylamide/styrene, acrylamide/maleic anhydride, and acrylamide/styrene/maleic anhydride were synthesized by the inverse emulsion polymerization technique. The presence of hydrophobic styrene and hydrophilic maleic anhydride monomers in the copolymer and terpolymer structure, provided some unique properties compared to polyacrylamide, was confirmed by several analyses including HNMR, elemental analysis, FTIR, SEM, TGA, and DSC. Simulating HTHS oil reservoir condition under high salinity, temperature, and shear rate, the rheological studies suggested unlike traditional EOR agents such as polyacrylamide, the viscosity of the copolymer, and terpolymer aqueous solutions showed a considerable increase after a critical polymer concentration and less reduction with the salt increment at both ambient and elevated temperatures. Furthermore, the swelling ratio of the insoluble terpolymers measured versus the time and temperature in salt water increased with the maleic anhydride mole fraction, decreased with the salt concentration, and showed a maximum value at around 57 °C. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47753.     

Evaluation of Rheological and Thermal Properties of a New Fluorocarbon Surfactant–Polymer System for EOR Applications in High-Temperature and High-Salinity Oil Reservoirs

Thermal stability and rheological properties of a novel surfactant–polymer system containing non‐ionic ethoxylated fluorocarbon surfactant was evaluated. A copolymer of acrylamide (AM) and 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) was used. Thermal stability and surfactant structural changes after aging at 100 °C were evaluated using TGA, ¹H NMR, ¹³C NMR, ¹⁹F NMR and FTIR. The surfactant was compatible with AM–AMPS copolymer and synthetic sea water. No precipitation of surfactant was observed in sea water. The surfactant was found to be thermally stable at 100 °C and no structural changes were detected after exposure to this temperature. Rheological properties of the surfactant–polymer (SP) system were measured in a high pressure rheometer. The effects of surfactant concentration, temperature, polymer concentration and salinity on rheological properties were studied for several SP solutions. At low temperature (50 °C), the viscosity initially increased slightly with the addition of the surfactant, then decreased at high surfactant concentration. At a high temperature (90 °C), an increase in the viscosity with the increase in surfactant concentration was not observed. Overall, the influence of the fluorocarbon surfactant on the viscosity of SP system was weak particularly at high temperatures and high shear rate. Salts present in sea water reduced the viscosity of the polymer due to a charge shielding effect. However, the surfactant was found to be thermally stable in the presence of salts.     

反相微乳液法合成耐温抗盐聚合物驱油剂

以丙烯酰胺（AM）、2-丙烯酰胺-2-甲基丙磺酸（AMPS）和甲基丙烯酸十八酯为单体,过硫酸钾（K2S2O8）-亚硫酸氢钠（NaHSO3）为氧化还原引发体系,Span60为乳化剂、煤油为分散相进行反相微乳液聚合,合成了驱油用耐温抗盐聚合物。研究了单体的加量、单体的浓度、引发剂的浓度、反应温度、pH值等因素对聚合物粘度的影响,并对产品的耐温抗盐性进行评价。结果表明：在AMPS加量为20%、甲基丙烯酸十八酯加量为1%、单体的浓度为25%、反应温度为53℃、引发剂浓度为0.4%、pH值为10、反应7～8h时,聚合物的粘度最大,并表现出良好的耐温抗盐性能。     

AM/AMPS/DMAM三元共聚物的合成及性能研究

为提高驱油用聚合物的耐温抗盐性,采用N,N-二甲基丙烯酰胺(DMAM)与2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)通过氧化还原引发剂体系聚合方法合成了AM/AMPS/DMAM三元共聚物,用正交实验法确定了最佳合成方案为:温度40℃,pH值为11,引发剂浓度为0.18%,单体浓度为13%,DMAM加量为2%。对共聚物的耐盐性及热稳定性进行测试,在标准盐水中共聚物为2500 mg/L,温度为30℃时,粘度可达到35.3 mPa.s;温度为90℃时,粘度为9.70 mPa.s。结果表明,AM/AMPS/DMAM三元共聚物具有较好的抗盐性能和增粘性能,但抗温效果并不明显,有待进一步改进。     

偏氯乙烯/丙烯腈/苯乙烯悬浮共聚合动力学

本文研究了偏氯乙烯（ＶＤＣ）／丙烯腈（ＡＮ）／苯乙烯（Ｓｔ）三元悬浮共聚合体系的聚合机理、共聚速率、非聚物组成及其特性粘度的影响因素。实验表明随着投料配比的改变,可分成四个不同聚合机理区域。Ｓｔ对ＶＤＣ／ＡＮ／Ｓｔ三元悬浮共聚有缓聚作用。ＶＤＣ三元悬浮共聚速率可用半经验模型,ｄＣ／ｄｔ＝αＣ＾β「Ⅰ」ｏ＾γｅｘｐ（－γｋｄｔ）描述,由实验得到模型参数γ值为２．２４,模型参数α、β是聚合温度与引发剂浓度的函数。ＶＤＣ－ＡＮ－Ｓｔ三元悬浮共聚物存在着较宽的ＶＤＣ组成分布,并受到单体ＡＮ水溶性的影响,经ＡＮ动态相平衡校正后,可预测ＶＤＣ三元共聚物组成。ＶＤＣ－ＡＮ－Ｓｔ共聚物的特性粘度随着转化率的升高而增大。在相同引发剂用量下,高转化率ＶＤＣ－ＡＮ－Ｓｔ共聚物特性粘度的对数与温度的倒数成线性关系。     

三次采油用耐温抗盐聚合物的研究进展

概述三次采油用耐温抗盐聚合物的研究进展,特别是在超高分子量聚丙烯酰胺、丙烯酰胺与耐温抗盐单体的共聚物、疏水缔合聚合物、新型结构的聚丙烯酰胺共聚物等几个热门领域上总结了较新的研究结果。     

Solution properties of ionic hydrophobically associating polyacrylamide with an arylalkyl group

Copolymers of acrylamide, 2‐acrylamide‐2‐methylpropanesulfate (AMPS), and hydrophobic monomer N‐arylalkylacrylamide (BAAM) were synthesized by free‐radical micellar copolymerization. The effects of the copolymer, BAAM, AMPS, and NaCl concentrations and the pH value on the apparent viscosity of the copolymers were studied. The solution viscosities increased sharply when the copolymer concentration was higher than the critical associating concentration. The apparent viscosities of aqueous solutions of poly(N‐arylalkylacrylamide‐co‐acrylamide‐co‐2‐acrylamide‐2‐methylpropanesulfate) (PBAMS) increased with increasing BAAM and AMPS concentrations. PBAMS exhibited good salt resistance. With increasing pH, the apparent viscosities first increased and then decreased. Dilute PBAMS solutions exhibited Newtonian behavior, whereas semidilute aqueous and salt solutions exhibited shear‐thickening behavior at a lower shear rate and pseudoplastic behavior at a higher rate. Upon the removal of shear, the aqueous solution viscosities recovered and became even greater than the original viscosity, but the salt solution viscosities could not recover instantaneously. The elastic properties of PBAMS solutions were more dominant than the viscous properties, and this suggested a significant buildup of a network structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 316–321, 2005     

三元共聚物P(IA/MA/AMPS)的合成及阻垢性能评价

以衣康酸(IA)、马来酸(MA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为单体,以过硫酸铵为引发剂,以水为溶剂,通过自由基聚合合成了一种新型的三元共聚物,探讨了单体配比、聚合温度、引发剂用量、聚合时间等合成条件对阻垢性能的影响,确定了最佳的合成条件为:单体配比n(IA)∶n(MA)∶n(AMPS)=1∶1∶1,聚合温度80℃,引发剂占单体质量分数的5%,聚合时间2h;用红外分光光度仪分析证明得到了预期的产物结构,并测定了产物的特性黏度和固含量。通过静态法对三元共聚物的阻垢性能进行评价,在加剂量为50mg/L时阻碳酸钙率最佳可达93.6%,是一种性能优异的阻垢剂。     

Synthesis and clay stabilization of a water‐soluble copolymer based on acrylamide,modular β‐cyclodextrin,and AMPS

A modular β‐cyclodextrin copolymer for clay stabilization was prepared from 2‐O‐(allyloxy‐2‐hydroxyl‐propyl)‐β‐cyclodextrin (XBH), acrylamide (AM), 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS), and sodium acrylate (NaAA) via redox free‐radical copolymerization. The effects of reactive conditions (such as initiator concentration, monomer ratio, reaction temperature, and pH) on the apparent viscosity of the copolymer were investigated and the optimal conditions for the copolymerization were established. The copolymer obtained was characterized by infrared spectroscopy, scanning electron microscope, viscosity measurements, rheological measurement, core stress test, and X‐ray diffractometry. The crystalline interspace of MMT could be reduced from 18.95323 Å to 15.21484 Å by copolymer AM/NaAA/AMPS/XBH. And this water‐soluble copolymer also showed remarkable anti‐shear ability, temperature resistance, and salt tolerance (1000 s^?1, viscosity retention rate: 35%; 120°C, viscosity retention rate: 75%; 10,000 mg/L NaCl, viscosity retention rate: 50.2%; 2000 mg/L CaCl₂, viscosity retention rate: 48.5%; 2000 mg/L MgCl₂, viscosity retention rate: 42.9%). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013