Статті в журналах: "Polymer solutions Viscosity"

1

Bertrand, Gary L. "Viscosity of polymer solutions." Journal of Chemical Education 69, no. 10 (October 1992): 818. http://dx.doi.org/10.1021/ed069p818.1.

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2

Konstantinov, Ivan, Carlos Villa, Rongjuan Cong, and Thomas Karjala. "Viscosity Modeling of Polymer Solutions." Macromolecular Symposia 377, no. 1 (February 2018): 1600179. http://dx.doi.org/10.1002/masy.201600179.

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3

Baloch, Musa Kaleem. "The Newtonian Viscosity of Polymer Solutions." Journal of Macromolecular Science: Part A - Chemistry 25, no. 4 (January 1988): 363–72. http://dx.doi.org/10.1080/00222338808053374.

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4

Tian, Quan, Ling Hui Sun, and Hui Hui Kou. "Study on Laboratory Evaluation of Temperature and Salt Resistance Polymer Solution." Applied Mechanics and Materials 488-489 (January 2014): 217–21. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.217.

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At present, China's late stage of oilfield most mining has been reached, there is high water content, and produced low levels problems. Polymer flooding enhanced oil recovery technology is important today, but Pam can't adapt oilfield tertiary oil recovery reservoir with heat resistance and salt. This article examines five kinds of rheological properties of polymer solutions under different salinity, studied under the same mineralized shear viscosity of different polymers. Experimental results show that the shear resistance capacity of 20 million ordinary polymer strong, 8 million and temperature of salt-tolerant associative polymer viscosity retention rates are highest. Less than 5,000 ppm 18 million under NaCl salinity salt resistant polymer viscosity highest salinity between 5,000 ppm NaCl to 15,000 ppm NaCl 8 million and temperature of salt-tolerant hydrophobically associating polymer solution viscosity of the highest.

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5

WEERAPOL, Yotsanan, and Pornsak SRIAMORNSAK. "Differences in Viscoelasticity of Ophthalmic Polymer Solution after Sterilization." Walailak Journal of Science and Technology (WJST) 17, no. 7 (July 1, 2020): 686–97. http://dx.doi.org/10.48048/wjst.2020.6341.

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Polymer solution has been used for increasing viscosity of ophthalmic solution in order to prolong the retention of active drug in the eye. The ophthalmic solution must be sterilized, which may affect the rheology properties of viscosity-inducing polymers. The aim of this study was to investigate the effect of sterilization treatment on viscosity-inducing agents (i.e., poloxamer, polyvinyl alcohol; (PVA), methyl cellulose (MC), polyvinylpyrrolidone (PVP) and carbomer). The effect of membrane filtration and steam sterilization or autoclaving (121 °C, 15 Ib/inch2, 15 min) were determined. A rheometer was used to investigate the viscosity and viscoelastic properties between treated and untreated polymer solutions. The power law model, consistency index (k), and power law index (n) of polymer solution viscosity were compared. For viscoelastic properties, storage modulus and loss modulus were examined. The results demonstrated that, viscosity of carbomer and MC solution (1 and 2 %) were changed after steam sterilization. No difference in viscosity was observed for PVP, PVA and poloxamer solution, between untreated and treated samples. The storage and loss moduli of PVA solution after autoclaving were not different when comparing with the untreated polymer solution. From this study, it could be concluded that the sterilization treatment influenced the viscosity behavior and viscoelastic properties of polymer solution used as viscosity-inducing agent in ophthalmic solution. Therefore, the selection of polymer and sterilization method should be carefully considered.

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6

LINDNER, ANKE, DANIEL BONN, EUGENIA CORVERA POIRÉ, MARTINE BEN AMAR, and JACQUES MEUNIER. "Viscous fingering in non-Newtonian fluids." Journal of Fluid Mechanics 469 (October 15, 2002): 237–56. http://dx.doi.org/10.1017/s0022112002001714.

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We study the viscous fingering or Saffman–Taylor instability in two different dilute or semi-dilute polymer solutions. The different solutions exhibit only one non-Newtonian property, in the sense that other non-Newtonian effects can be neglected. The viscosity of solutions of stiff polymers has a strong shear rate dependence. Relative to Newtonian fluids, narrower fingers are found for rigid polymers. For solutions of flexible polymers, elastic effects such as normal stresses are dominant, whereas the shear viscosity is almost constant. Wider fingers are found in this case. We characterize the non-Newtonian flow properties of these polymer solutions completely, allowing for separate and quantitative investigation of the influence of the two most common non-Newtonian properties on the Saffman–Taylor instability. The effects of the non-Newtonian flow properties on the instability can in all cases be understood quantitatively by redefining the control parameter of the instability.

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7

Zhong, Huiying, Qiuyuan Zang, Hongjun Yin, and Huifen Xia. "Experimental Study on Medium Viscosity Oil Displacement Using Viscoelastic Polymer." Geofluids 2018 (November 29, 2018): 1–11. http://dx.doi.org/10.1155/2018/4321380.

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With the growing demand for oil energy and a decrease in the recoverable reserves of conventional oil, the development of viscous oil, bitumen, and shale oil is playing an important role in the oil industry. Bohai Bay in China is an offshore oilfield that was developed through polymer flooding process. This study investigated the pore-scale displacement of medium viscosity oil by hydrophobically associating water-soluble polymers and purely viscous glycerin solutions. The role and contribution of elasticity on medium oil recovery were revealed and determined. Comparing the residual oil distribution after polymer flooding with that after glycerin flooding at a dead end, the results showed that the residual oil interface exhibited an asymmetrical “U” shape owing to the elasticity behavior of the polymer. This phenomenon revealed the key of elasticity enhancing oil recovery. Comparing the results of polymer flooding with that of glycerin flooding at different water flooding sweep efficiency levels, it was shown that the ratio of elastic contribution on the oil displacement efficiency increased as the water flooding sweep efficiency decreased. Additionally, the experiments on polymers, glycerin solutions, and brines displacement medium viscosity oil based on a constant pressure gradient at the core scale were carried out. The results indicated that the elasticity of the polymer can further reduce the saturation of medium viscosity oil with the same number of capillaries. In this study, the elasticity effect on the medium viscosity oil interface and the elasticity contribution on the medium viscosity oil were specified and clarified. The results of this study are promising with regard to the design and optimum polymers applied in an oilfield and to an improvement in the recovery of medium viscosity oil.

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8

Pamies, R., M. C. Lopez Martinez, J. G. Hernandez Cifre, and J. Garcia de la Torre. "Non-Newtonian Viscosity of Dilute Polymer Solutions." Macromolecules 38, no. 4 (February 2005): 1371–77. http://dx.doi.org/10.1021/ma0482617.

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9

Takahashi, Yoshiaki, Fumitoshi Suzuki, Masahiko Miyachi, Ichiro Noda, and Mitsuru Nagasawa. "Zero-Shear Viscosity of Branched Polymer Solutions." Polymer Journal 18, no. 1 (January 1986): 89–94. http://dx.doi.org/10.1295/polymj.18.89.

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10

Sridhar, T., V. Tirtaatmadja, D. A. Nguyen, and R. K. Gupta. "Measurement of extensional viscosity of polymer solutions." Journal of Non-Newtonian Fluid Mechanics 40, no. 3 (November 1991): 271–80. http://dx.doi.org/10.1016/0377-0257(91)87012-m.

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11

Lee, Jae Keun, and Gyo Taeg Seo. "Apparent elongational viscosity of dilute polymer solutions." Korean Journal of Chemical Engineering 13, no. 6 (November 1996): 554–58. http://dx.doi.org/10.1007/bf02706020.

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12

Subirana, Juan A. "Non-newtonian viscosity of dilute polymer solutions." Journal of Polymer Science Part C: Polymer Symposia 16, no. 3 (March 7, 2007): 1423–31. http://dx.doi.org/10.1002/polc.5070160320.

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13

Jiang, Wenchao, Zhaowei Hou, Xiaolin Wu, Kaoping Song, Erlong Yang, Bin Huang, Chi Dong, et al. "A New Method for Calculating the Relative Permeability Curve of Polymer Flooding Based on the Viscosity Variation Law of Polymer Transporting in Porous Media." Molecules 27, no. 12 (June 20, 2022): 3958. http://dx.doi.org/10.3390/molecules27123958.

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Relative permeability of polymer flooding plays a very important role in oil field development. This paper aimed to measure and calculate the relative permeability curves of polymer flooding more accurately. First, viscosity variation law of polymer in porous media was studied. Rock particles of different diameters and cementing agent were used to make artificial cores and hydrophobically associating polymer solutions were prepared for experiments. Polymer solutions were injected into the cores filled with crude oil and irreducible water. In the process of polymer flooding, produced fluid was collected at different water saturations and locations of the core. Polymer solutions were separated and their viscosities were measured. With the experimental data, the viscosity variation rule of polymer transporting in porous media was explored. The result indicates that the viscosity retention rate of polymer solutions transporting in porous media has power function relationship with the water saturation and the dimensionless distance from the core inlet. Finally, the relative permeability curves of polymer flooding were measured by unsteady state method and the viscosity variation rule was applied to the calculation of the relative permeability curves.

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14

Sato, Takahiro. "Rheology of stiff-chain polymer solutions." Journal of Rheology 66, no. 2 (March 2022): 399–414. http://dx.doi.org/10.1122/8.0000397.

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Theoretical expressions for the intrinsic viscosity, the Huggins coefficient, zero-shear viscosity, and storage and loss moduli for stiff-chain polymer solutions are reviewed. Especially, the mean-field Green function method is explained in detail to consider the intermolecular collision effect on the rheological properties of concentrated stiff-chain polymer solutions, by applying the method to monodisperse and polydisperse straight cylinders and monodisperse fuzzy cylinder models. The theoretical expressions reviewed are compared with experimental results for aqueous solutions of two rigid helical polysaccharides, schizophyllan and xanthan.

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15

Chandra, Bidhan, V. Shankar, and Debopam Das. "Onset of transition in the flow of polymer solutions through microtubes." Journal of Fluid Mechanics 844 (April 16, 2018): 1052–83. http://dx.doi.org/10.1017/jfm.2018.234.

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Experiments are performed to characterize the onset of laminar–turbulent transition in the flow of high-molecular-weight polymer solutions in rigid microtubes of diameters in the range $390~\unicode[STIX]{x03BC}\text{m}{-}470~\unicode[STIX]{x03BC}\text{m}$ using the micro-PIV technique. By considering flow in tubes of such small diameters, the present study probes higher values of elasticity numbers ($E\equiv \unicode[STIX]{x1D706}\unicode[STIX]{x1D708}/R^{2}$) compared to existing studies, where $\unicode[STIX]{x1D706}$ is the longest relaxation time of the polymer solution, $R$ is the tube radius and $\unicode[STIX]{x1D708}$ is the kinematic viscosity of the polymer solution. For the Newtonian case, our experiments indicate that the natural transition (without the aid of any forcing mechanism) occurs at Reynolds number ($Re$) $2000\pm 100$. As the concentration of polymer is increased, initially there is a delay in the onset of the transition and the transition Reynolds number increases to $2500$. Further increase in concentration of the polymer results in a decrease in the Reynolds number for transition. At sufficiently high concentrations, the added polymer tends to destabilize the flow and the transition is observed to happen at $Re$ as low as $800$. It is also observed that the addition of polymers, regardless of their concentration, reduces the magnitude of the velocity fluctuations after transition. Dye-stream visualization is further used to corroborate the onset of transition in the flow of polymer solutions. The present work thus shows that addition of polymer, at sufficiently high concentrations, destabilizes the flow when compared to that of a Newtonian fluid, thereby providing additional evidence for ‘early transition’ or ‘elasto-inertial turbulence’ in the flow of polymer solutions. The data for the transition Reynolds number $Re_{t}$ from our experiments (for tubes of different diameters, and for two different polymers at varying concentrations) collapse well according to the scaling relation $Re_{t}\propto 1/\sqrt{E(1-\unicode[STIX]{x1D6FD})}$, where $\unicode[STIX]{x1D6FD}$ is the ratio of solvent viscosity to the viscosity of the polymer solution.

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16

Ohgita, Takashi, Naoki Hayashi, Naomasa Gotoh, and Kentaro Kogure. "Suppression of type III effector secretion by polymers." Open Biology 3, no. 12 (December 2013): 130133. http://dx.doi.org/10.1098/rsob.130133.

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Bacteria secrete effector proteins required for successful infection and expression of toxicity into host cells. The type III secretion apparatus is involved in these processes. Previously, we showed that the viscous polymer polyethylene glycol (PEG) 8000 suppressed effector secretion by Pseudomonas aeruginosa . We thus considered that other viscous polymers might also suppress secretion. We initially showed that PEG200 (formed from the same monomer (ethylene glycol) as PEG8000, but which forms solutions of lower viscosity than the latter compound) did not decrease effector secretion. By contrast, alginate, a high-viscous polymer formed from mannuronic and guluronic acid, unlike PEG8000, effectively inhibited secretion. The effectiveness of PEG8000 and alginate in this regard was closely associated with polymer viscosity, but the nature of viscosity dependence differed between the two polymers. Moreover, not only the natural polymer alginate, but also mucin, which protects against infection, suppressed secretion. We thus confirmed that polymer viscosity contributes to the suppression of effector secretion, but other factors (e.g. electrostatic interaction) may also be involved. Moreover, the results suggest that regulation of bacterial secretion by polymers may occur naturally via the action of components of biofilm or mucin layer.

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17

Akhmetkhanov, Rinat M., Valentina V. Chernova, Angela S. Shurshina, Mariya Yu Lazdina, and Elena I. Kulish. "Study of the formation of structures in solutions of chitosan – polyvinyl alcohol polymer blends." Kondensirovannye sredy i mezhfaznye granitsy = Condensed Matter and Interphases 23, no. 2 (June 4, 2021): 188–95. http://dx.doi.org/10.17308/kcmf.2021.23/3428.

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The aim of this work was the investigation of the formation of structures in solutions of individual polymers, as well as their blends with each other in buffer solvents with different values of pH. In this study we used a sample of chitosan (degree of deacetylation ~ 84 %, M = 130,000), which is a polycation when dissolved, and polyvinyl alcohol (r = 1.25 g/cm3, M = 5000). Buffer systems based on acetic acid and sodium acetate with pH = 3.8, 4.25, and 4.75 were used as solvents. Viscosimetry was used to determine the intrinsic viscosity, the degree of structuring, and the Huggins constant. The Kriegbaum method was used to determine the nature of the aggregates formed by the blend of the studied polymers. In the course of the research, it was shown that an increase in the pH of the acetate buffer used as a solvent was accompanied by a compression of the macromolecular coil (a decrease in intrinsic viscosity values), a deterioration in the quality of thesolvent (an increase in Huggins constant values), and an increase in the degree of polymer aggregation in a solution for chitosan polyelectrolyte. At the same time for a solution of polyvinyl alcohol the pH of the buffer practically did not affect the nature of the polymer-solvent interaction. It has been proved that polymer blends are characterized by an increase in aggregation processes and a decrease in the thermodynamic quality of the solvent in comparison with solutions of individual polymers. The size of the “combined” macromolecular coil, characterized by the intrinsic viscosity value for the polymer blend, which can be both above (buffer solvent with pH = 3.80) and below (buffer solvent with pH = 4.25 and 4.75) additivevalues, changed depending on the type of formed polymer-polymer aggregates (homo- or hetero-). It was established that the type of aggregates (homo- or hetero-) formed in solutions of polymer blends was determined not only by the thermodynamic quality of the used solvents, but also by the concentration of the polymers in the initial solutions

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18

Zechner, Markus, Torsten Clemens, Ajay Suri, and Mukul M. Sharma. "Simulation of Polymer Injection Under Fracturing Conditions—An Injectivity Pilot in the Matzen Field, Austria." SPE Reservoir Evaluation & Engineering 18, no. 02 (March 23, 2015): 236–49. http://dx.doi.org/10.2118/169043-pa.

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Summary Polymer flooding leads to enhanced oil recovery by accelerating oil production and improving sweep efficiency. However, because of the higher viscosity, the injectivity of polymer solutions is of some concern and is important to understand to predict incremental oil recoveries. Achieving high polymer-injection rates is required to increase oil-production rates. In the field test performed in the Matzen field (Austria), polyacrylamide polymers were injected for the past 2 years. Coreflood experiments with these polymers showed a significant increase in apparent viscosity because of the viscoelastic properties of the polymer solutions. Also, severe degradation of the polymer solution at high flow velocities was detected. In addition to coreflood experiments, flow experiments through fractures were performed. In these experiments, shear thinning and limited degradation of the polymer solution were observed and quantified. Detailed polymer-injection simulations were conducted that included complex polymer rheology in the fractures and the matrix. The reservoir stress changes and their effects on the fractures were also taken into account as a result of cold-polymer injection. The results of the simulations matched the field data both for waterfloods and polymer-test floods. The simulations revealed two distinct phases during the injection of the polyacrylamide-polymer solution: Injection under matrix conditions in an early phase resulting in severe degradation of the polymers Injection under fracturing conditions after the formation parting pressure is reached, leading to limited degradation of the polymers The calibrated model was used to investigate the impact of polymer rheology and particle plugging on injectivity and fracture growth. The results of the field test and the simulations indicate that screening of fields for polyacrylamide-polymer projects needs to include geomechanical properties of the reservoir sand and cap/base rock in addition to the conventional parameters used in screening such as oil viscosity, water salinity, reservoir temperature, and reservoir permeability.

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19

OUELLETTE, NICHOLAS T., HAITAO XU, and EBERHARD BODENSCHATZ. "Bulk turbulence in dilute polymer solutions." Journal of Fluid Mechanics 629 (June 15, 2009): 375–85. http://dx.doi.org/10.1017/s0022112009006697.

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By tracking small particles in the bulk of an intensely turbulent laboratory flow, we study the effect of long-chain polymers on the Eulerian structure functions. We find that the structure functions are modified over a wide range of length scales even for very small polymer concentrations. Their behaviour can be captured by defining a length scale that depends on the solvent viscosity, the polymer relaxation time and the Weissenberg number. This result is not captured by current models. Additionally, the effects we observe depend strongly on the concentration. While the dissipation-range statistics change smoothly as a function of polymer concentration, we find that the inertial-range values of the structure functions are modified only when the concentration exceeds a threshold of approximately 5 parts per million (p.p.m.) by weight for the 18 × 106 atomic mass unit (a.m.u.) molecular weight polyacrylamide used in the experiment.

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20

Chen, Tingting, Xingqin Fu, Luzi Zhang, and Yuejun Zhang. "Viscosity Behavior of P(DAC-AM) with Serial Cationicity and Intrinsic Viscosity in Inorganic Salt Solutions." Polymers 11, no. 12 (November 26, 2019): 1944. http://dx.doi.org/10.3390/polym11121944.

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The poly(acryloyloxyethyl trimethyl ammonium chloride–co–acrylamide), P(DAC-AM), is a kind of cationic polyelectrolyte usually applied in a solution form, and its performance is affected by its structure and the environment where it is used. In particular, its viscosity properties in salt solutions are directly related to its efficacy in various applications, and the performance is one of the most important solution properties. Therefore, in this paper, the effects of the salt concentration and valence of seven kinds of inorganic salts, NaCl, LiCl, KCl, MgCl2, AlCl3, Na2SO4, and Na3PO4, on the values of apparent viscosity (ηa) of P(DAC-AM) samples with cationicity of 10%, 50%, and 90%, and intrinsic viscosity ([η]) of 5, 10, and 15 dL/g were investigated. The ηa was determined using a rotational viscometer. The interaction mechanism between the polymers and salt ions was also investigated. The results showed that depending on the salt concentration, the ηa firstly decreased sharply to the inflection point which indicated the minimum volume of the molecule shrinking, and then either maintained the value unchanged or increased. The salt concentration corresponding to the inflection point decreased with the increase of the salt ion valence but with the reduction of the cationicity of the polymer. The ηa at the inflection point increased as the [η] of the polymer grew. This indicated that the salt concentration and the salt ion valence had a notable impact on the stretch of the cationic polymer molecule in the salt solutions. It was discovered that the phenomenon of the increase of the ηa of P(DAC-AM) samples in the multivalent salt solutions after the inflection point was caused by not only the increase of the ηa of the complexes formed from the pure salts, but also the viscosity resistance of the charge and volume between the polymer molecules and salt ions, as well as the complexes themselves. The linear relationship between the increased ηa and the salt concentration, representing the interaction both among the complexes themselves and between the polymer and complexes, was obtained. Furthermore, the interaction model between the salt ions and P(DAC-AM) molecules in a wide range of salt concentrations was illustrated.

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21

Amaya-Gómez, M. P., L. M. Sanabria-Rivas, A. M. Díaz-Lasprilla, C. Ardila-Suárez, R. H. Castro-García, H. I. Quintero-Pérez, and G. E. Ramírez-Caballero. "Copolymer Based on Polyglycerol-Acrylate-Lactate as Potential Water Viscosifier and Surfactant for Enhanced Oil Recovery." International Journal of Polymer Science 2020 (November 2, 2020): 1–9. http://dx.doi.org/10.1155/2020/3464670.

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Polymer and surfactant flooding are widely applied processes in enhanced oil recovery (EOR) in which viscous polymers or surfactants aqueous solutions are introduced in oil reservoirs to rise the recovery of the remaining oil. In this regard, one of the challenges of EOR practices is the use of efficient but low-cost viscosifier and surfactant polymers. This work is aimed at synthesizing a polyglycerol derived from the biodegradable and nontoxic monomer, glycerol, and evaluating the effect of its copolymerization on rheological and interfacial properties, which were tested in water and brine for the former and in the water/oil system for the last properties. The copolymers were synthesized using a polyglycerol backbone, acrylic acid, lactic acid, and oleic acid. The chemical structure of copolymers was characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TG), and differential scanning calorimetry (DSC). The viscosity and the interfacial tension (IFT) of polymeric solutions were tested. Thus, the viscosity and surface performance of the prepared polymer solutions in distilled water and brine were analyzed according to the structure of the synthesized polymers. The results showed that the synthesized polymers modified water viscosity and surface tension between water and oil. The developed polymers could be candidates for applications in enhanced oil recovery and related applications.

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22

Guo, Xiaodie, Xuejiao Chen, Wenjing Zhou, and Jinjia Wei. "Effect of Polymer Drag Reducer on Rheological Properties of Rocket Kerosene Solutions." Materials 15, no. 9 (May 6, 2022): 3343. http://dx.doi.org/10.3390/ma15093343.

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Adding drag reduction agent (DRA) to rocket kerosene is an effective way to reduce the pipeline resistance of rocket kerosene transportation systems. However, so far, there have been few research reports on the effect of DRA on the rheological properties of rocket kerosene solution, especially from a microscopic perspective. In this study, coarse-grained molecular dynamics simulations were conducted to investigate the rheological properties of rocket kerosene solutions with DRAs of different chain lengths and concentrations. The results showed that the viscosity of DRA—kerosene solution is generally higher than that of pure kerosene at a low shear rate, while with an increase in shear rate, the viscosity of DRA—kerosene solution decreases rapidly and finally tends to become similar to that of pure kerosene. The shear viscosity of DRA—kerosene solution increases with an increase in chain length and concentration of polymers. Through observing the morphologic change of DRA molecules and analyzing the radius of gyration and the mean-squared end-to-end distance of polymers, it was confirmed that the rheological properties of DRA—kerosene solutions are strongly related to the degree of entanglement of polymer chains. The simulation results provide microscopic insights into the rheological behavior of DRA—kerosene solutions and clarify the intrinsic relation between the morphologic change of polymer molecules and the rheological properties of DRA—kerosene solutions.

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23

Alzaabi, Mohamed Adel, Jørgen Gausdal Jacobsen, Shehadeh Masalmeh, Ali Al Sumaiti, Øystein Pettersen, and Arne Skauge. "Polymer Injectivity Test Design Using Numerical Simulation." Polymers 12, no. 4 (April 3, 2020): 801. http://dx.doi.org/10.3390/polym12040801.

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Polymer flooding is an enhanced oil recovery (EOR) process, which has received increasing interest in the industry. In this process, water-soluble polymers are used to increase injected water viscosity in order to improve mobility ratio and hence improve reservoir sweep. Polymer solutions are non-Newtonian fluids, i.e., their viscosities are shear dependent. Polymers may exhibit an increase in viscosity at high shear rates in porous media, which can cause injectivity loss. In contrast, at low shear rates they may observe viscosity loss and hence enhance the injectivity. Therefore, due to the complex non-Newtonian rheology of polymers, it is necessary to optimize the design of polymer injectivity tests in order to improve our understanding of the rheology behavior and enhance the design of polymer flood projects. This study has been addressing what information that can be gained from polymer injectivity tests, and how to design the test for maximizing information. The main source of information in the field is from the injection bottom-hole pressure (BHP). Simulation studies have analyzed the response of different non-Newtonian rheology on BHP with variations of rate and time. The results have shown that BHP from injectivity tests can be used to detect in-situ polymer rheology.

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24

SATO, Takahiro. "Molecular Theory on the Viscosity of Polymer Solutions." KOBUNSHI RONBUNSHU 69, no. 11 (2012): 613–22. http://dx.doi.org/10.1295/koron.69.613.

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25

Cardaliaguet, Pierre, Olivier Ley, and Aurelien Monteillet. "Viscosity solutions for a polymer crystal growth model." Indiana University Mathematics Journal 60, no. 3 (2011): 895–936. http://dx.doi.org/10.1512/iumj.2011.60.4322.

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26

Ferguson, J., and N. E. Hudson. "Elongational Viscosity and Relaxation Processes in Polymer Solutions." International Journal of Polymeric Materials and Polymeric Biomaterials 20, no. 3-4 (April 1993): 181–91. http://dx.doi.org/10.1080/00914039308048360.

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27

Kalashnikov, V. N. "Shear‐rate dependent viscosity of dilute polymer solutions." Journal of Rheology 38, no. 5 (September 1994): 1385–403. http://dx.doi.org/10.1122/1.550550.

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28

Lodge, Arthur S. "Polymer Solutions and Melts: Viscosity, Diffusion, and Elasticity." Industrial & Engineering Chemistry Research 34, no. 10 (October 1995): 3355–58. http://dx.doi.org/10.1021/ie00037a022.

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29

Jones, D. M., K. Walters, and P. R. Williams. "On the extensional viscosity of mobile polymer solutions." Rheologica Acta 26, no. 1 (January 1987): 20–30. http://dx.doi.org/10.1007/bf01332680.

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30

Moan, M., and A. Magueur. "Transient extensional viscosity of dilute flexible polymer solutions." Journal of Non-Newtonian Fluid Mechanics 30, no. 2-3 (January 1988): 343–54. http://dx.doi.org/10.1016/0377-0257(88)85033-x.

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31

RAO, M. "Viscosity of dilute to moderately concentrated polymer solutions." Polymer 34, no. 3 (1993): 592–96. http://dx.doi.org/10.1016/0032-3861(93)90555-o.

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32

Baloch, Musa Kaeem. "The Newtonian viscosity of polymer solutions: Scaling relationships." Journal of Macromolecular Science, Part B 27, no. 2-3 (June 1988): 151–80. http://dx.doi.org/10.1080/00222348808245761.

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33

Song, Yuhua, Paul M. Mathias, David Tremblay, and Chau-Chyun Chen. "Liquid Viscosity Model for Polymer Solutions and Mixtures." Industrial & Engineering Chemistry Research 42, no. 11 (May 2003): 2415–22. http://dx.doi.org/10.1021/ie030023x.

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34

Dutta, A., and R. A. Mashelkar. "On a generalised viscosity equation for polymer solutions." Rheologica Acta 25, no. 3 (May 1986): 321–25. http://dx.doi.org/10.1007/bf01357959.

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35

Parisi, Daniele, Colin D. Ditillo, Aijie Han, Seth Lindberg, Mark W. Hamersky, and Ralph H. Colby. "Rheological investigation on the associative properties of poly(vinyl alcohol) solutions." Journal of Rheology 66, no. 6 (November 2022): 1141–50. http://dx.doi.org/10.1122/8.0000435.

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We report intrinsic viscosity and flow curve measurements on a set of five industrial poly(vinyl alcohol) (PVOH) samples, with varying degree of hydrolysis, molecular weight, and concentration in two solvents: water and dimethyl sulfoxide (DMSO). Aqueous poly(vinyl alcohol) solutions exhibit clear features of associative polymers, and the hydroxyl-carbonyl hydrogen bonds seem to dominate polymer chain associations. We propose a “sticky-blob” model, applicable to any associating polymer solution with many stickers inside each correlation blob, which predicts the concentration dependence of the specific viscosity and the chain relaxation time in the entanglement regime. When PVOH polymers are dissolved in DMSO, a strong hydrogen bond acceptor, chain-chain associations are fully prevented for all relevant degrees of hydrolysis. The specific viscosity and the relaxation time of the chain recover the expected concentration dependences for nonassociating flexible polymers in DMSO. The same concentration dependences are exhibited by literature data on 100% hydrolyzed PVOH in water, as the acetate content, dominating interchain associations, is zero. Comparing entangled aqueous and DMSO solutions at the same concentration enables the experimental measure of the time delay due to associations as the ratio between the terminal relaxation time of solutions in water and DMSO. The concentration dependence of such a time delay was also captured by the simple sticky-blob model introduced in this work.

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36

Pinault, Thomas, Bruno Andrioletti, and Laurent Bouteiller. "Chain stopper engineering for hydrogen bonded supramolecular polymers." Beilstein Journal of Organic Chemistry 6 (September 21, 2010): 869–75. http://dx.doi.org/10.3762/bjoc.6.102.

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Supramolecular polymers are linear chains of low molar mass monomers held together by reversible and directional non-covalent interactions, which can form gels or highly viscous solutions if the self-assembled chains are sufficiently long and rigid. The viscosity of these solutions can be controlled by adding monofunctional compounds, which interact with the chain extremities: chain stoppers. We have synthesized new substituted ureas and thioureas and tested them as chain stoppers for a bis-urea based supramolecular polymer. In particular, the bis-thiourea analogue of the bis-urea monomer is shown not to form a supramolecular polymer, but a good chain stopper, because it is a strong hydrogen bond donor and a weak acceptor. Moreover, all substituted ureas tested reduce the viscosity of the supramolecular polymer solutions, but the best chain stopper is obtained when two hydrogen bond acceptors are placed in the same relative position as for the monomer and when no hydrogen bond donor is present.

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37

Wang, Yue, Guang Sheng Cao, Gui Long Wang, Sheng Kun Sun, and Xin Li. "The Experiment of Viscosity Loss Caused by the Polymer Flow along Transportation Pipeline." Applied Mechanics and Materials 733 (February 2015): 59–62. http://dx.doi.org/10.4028/www.scientific.net/amm.733.59.

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By using polymer solution with high viscosity, polymer flooding can enhance oil recovery by reducing the mobility ratio of displacing fluid and oil in formation. Therefore, the core of polymer flooding's ground transportation is to keep the viscosity of polymer solution unchanged. According to the process layout of polymer ground transportation, the experimental device was designed and manufactured to determine viscosity loss of pipelines and elbow. We obtained the viscosity loss variation law of the polymer solutions of different concentrations at different flow velocities when they flow through the pipeline and elbow. The experimental results showed that the viscosity of polymer solution will decrease after the polymer solution flow through pipelines and elbow, due to the shear effect. The higher the velocity, the more significant the viscosity loss.

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38

Wagner, Manfred H., Esmaeil Narimissa, Leslie Poh, and Taisir Shahid. "Modeling elongational viscosity and brittle fracture of polystyrene solutions." Rheologica Acta 60, no. 8 (June 14, 2021): 385–96. http://dx.doi.org/10.1007/s00397-021-01277-1.

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AbstractElongational viscosity data of well-characterized solutions of 3–50% weight fraction of monodisperse polystyrene PS-820k (molar mass of 820,000 g/mol) dissolved in oligomeric styrene OS8.8 (molar mass of 8800 g/mol) as reported by André et al. (Macromolecules 54:2797–2810, 2021) are analyzed by the Extended Interchain Pressure (EIP) model including the effects of finite chain extensibility. Excellent agreement between experimental data and model predictions is obtained, based exclusively on the linear-viscoelastic characterization of the polymer solutions. The data were obtained by a filament stretching rheometer, and at high strain rates and lower polymer concentrations, the stretched filaments fail by rupture before reaching the steady-state elongational viscosity. Filament rupture is predicted by a criterion for brittle fracture of entangled polymer liquids, which assumes that fracture is caused by scission of primary C-C bonds of polymer chains when the strain energy reaches the bond-dissociation energy of the covalent bond (Wagner et al., J. Rheology 65:311–324, 2021).

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39

Gampert, Bernhard, Christoph Wilkes, and Thomas Eich. "The Viscosity of Extremely Low Concentrated Anionic Polyelectrolyte Solutions." Applied Rheology 9, no. 4 (August 1, 1999): 158–64. http://dx.doi.org/10.1515/arh-2009-0011.

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Abstract Polyelectrolytes are macromolecules which carry a large quantity of ionizable groups along their chains. By dissolving them in suitable solvents, for example water, these groups dissociate in highly charged macroions and an equivalent quantity of low-molecular counter ions. Through the connection between polymer and electrolyte properties this class of materials obtains its peculiar characteristic behaviour. The experiments undertaken here, were carried out using a commercial, anionic polyacrylamide with different hydrolysis factors in aqueous solutions. The reduced viscosity reaches a maximum which depends on the polymer concentration. The maximum also depends on the molar mass and is a function of the hydrolysis factor of the polymer.

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40

Unni, Mythreyi, Shehaab Savliwala, Brittany D. Partain, Lorena Maldonado-Camargo, Qingteng Zhang, Suresh Narayanan, Eric M. Dufresne, et al. "Fast nanoparticle rotational and translational diffusion in synovial fluid and hyaluronic acid solutions." Science Advances 7, no. 27 (June 2021): eabf8467. http://dx.doi.org/10.1126/sciadv.abf8467.

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Nanoparticles are under investigation as diagnostic and therapeutic agents for joint diseases, such as osteoarthritis. However, there is incomplete understanding of nanoparticle diffusion in synovial fluid, the fluid inside the joint, which consists of a mixture of the polyelectrolyte hyaluronic acid, proteins, and other components. Here, we show that rotational and translational diffusion of polymer-coated nanoparticles in quiescent synovial fluid and in hyaluronic acid solutions is well described by the Stokes-Einstein relationship, albeit with an effective medium viscosity that is much smaller than the macroscopic low shear viscosity of the fluid. This effective medium viscosity is well described by an equation for the viscosity of dilute polymer chains, where the additional viscous dissipation arises because of the presence of the polymer segments. These results shed light on the diffusive behavior of polymer-coated inorganic nanoparticles in complex and crowded biological environments, such as in the joint.

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41

Mori, Noriyasu, Taro Nisimura, and Kiyoji Nakamura. "Measurement of the extensional viscosity for polymer solutions and of fine particle containing polymer solutions." Sen'i Kikai Gakkaishi (Journal of the Textile Machinery Society of Japan) 43, no. 7 (1990): T62—T67. http://dx.doi.org/10.4188/transjtmsj.43.7_t62.

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42

Kuleznev, V. N., and L. B. Kandyrin. "Mechanical behaviour of polymer mixtures in the phase separation region." Canadian Journal of Chemistry 73, no. 11 (November 1, 1995): 1966–71. http://dx.doi.org/10.1139/v95-243.

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The liquid–liquid phase transition triggered by changes in the composition of polymer mixtures in solution or melt is often accompanied by "critical" opalescence, which signals the appearance of a microemulsion in the mixture. The viscosity of the polymer mixture in this region is characterized by a sharp minimum, observed, as a rule, over an extremely narrow range of concentration. Depending on the concentration of the solution, the type of polymer, and the solvent, the viscosity may decrease by a factor of 8–10. On transition from micro- to macro-separation, viscosity rapidly increases back to the original level. Changes in the composition of the mixture can alter the concentration at which phase separation occurs, but the minimum in viscosity invariably corresponds to the moment of phase separation. The critical opalescence region represents the formation of phase particles up to 80–100 nm in size, and this corresponds to the point of viscosity drop. This effect is due to the appearance of thermodynamically stable microemulsions in the polymer mixture, in the region between the binodal and the spinodal in the phase diagram. These emulsions are characterized by lower molecular interaction of incompatible polymers in the highly developed interfacial layer. Extremal changes at the point of phase separation are also observed for other mechanical characteristics of polymer mixtures in solutions or melts, for example, G′ and G″ dynamic moduli or complex viscosity η*. Keywords: polyblends, critical phenomena, viscosity, emulsions, phase separation.

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43

Azad, Madhar S., and Japan J. Trivedi. "Extensional Effects during Viscoelastic Polymer Flooding: Understanding Unresolved Challenges." SPE Journal 25, no. 04 (April 27, 2020): 1827–41. http://dx.doi.org/10.2118/201112-pa.

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Summary Several studies have tried to relate polymers’ enhanced oil recovery (EOR) potential to their viscoelastic characteristics such as onset, rheo thickening, extensional viscosity, and Deborah number (De). Contradictions prevail when it comes to reduction in residual oil saturation (Sor) during polymer flooding and the role of extensional properties. De calculated using the oscillatory relaxation time fails to explain the different pressure profiles exhibited by the viscous and viscoelastic polymers. Extensional viscosity has been ignored in many studies as the reason for additional Sor reduction based on the core-scale apparent viscosity and core-scale capillary number (Nc). In recent studies, a significant oil mobilization was shown by the viscoelastic polymers even before the critical Nc, which indicates that the capillary theory breaks out under specific conditions during polymer flooding. Moreover, the additional residual oil recovery caused by the high-salinity polymer solutions cannot be explained by the oscillatory De. In this paper, we compile and examine many such unresolved challenges from various literature with rheological and petrophysical insights. The uniaxial bulk extensional rheology is performed on the relevant polymers using a capillary breakup extensional rheometer to measure the extensional relaxation time, maximum extensional viscosity at the critical De, and strain hardening index. A detailed analysis signifies the role of extensional rheology on the viscoelastic onset, rheo thickening, and Sor reduction even under varying salinity conditions. The results also highlight the advantages of extensional rheology over oscillatory rheology and validate the capillary theory using modified capillary number.

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44

Dou, Xiangji, An Wang, Shikai Wang, Dongdong Shao, Guoqiang Xing, and Kun Qian. "Study on the Viscosity Optimization of Polymer Solutions in a Heavy Oil Reservoir Based on Process Simulation." Energies 15, no. 24 (December 14, 2022): 9473. http://dx.doi.org/10.3390/en15249473.

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Polymer flooding has been proved by many scholars for use in heavy oil reservoirs. However, due to mobility control effects and injectivity, selecting the appropriate solution viscosity is essential. It is difficult to form a deep understanding of the effect and mechanism of polymer flooding using conventional experimental methods with oil recovery as the reference standard, so it is necessary to conduct further study with the aid of simulation methods. In this study, a one-dimensional displacement mathematical model based on the Buckley–Leverett theory was established, and in the range of water–oil viscosity ratio from 0.1 to 0.6, the variation of water saturation along the flow caused by polymer solution was studied. The research results showed that under the action of a polymer solution, compared with water flooding, there was a decreasing region of water saturation along the flow due to oil phase accumulation. The larger the water–oil viscosity ratio, the larger the area of water saturation decline and the greater the degree of water saturation decline, resulting in a better the displacement effect. However, under the condition of oil–phase viscosity of 70 mPa·s, when the water–oil viscosity ratio reached 0.4, the range and degree of water saturation decline along the way no longer changed, all the crude oil that could be swept had been displaced, and the outlet end was close to producing only water, not oil; therefore, further increasing the water–oil viscosity ratio could not increase the oil recovery. At the same time, the increase in pressure had not changed, that is, the increase in pressure had not resulted in the same increase in oil recovery. When the viscosity of oil phase increased to 140 mPa·s, the same rule was displayed, the appropriate water–oil viscosity ratio was also 0.4. The paper analyzed the action mechanism of polymer solution through process description, and the results provided a clear selection method for selecting reasonable polymer solution concentration, as well as a reference for polymer solution range under different crude oil viscosity conditions.

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45

Shi, Lei Ting, Xiao Nan Li, Wei Zhou, Song Xia Wang, Qiong Yang, Zhong Bin Ye, and Jian Zhang. "Study on Properties of Pectinate Hydrophobically Associating Polyacrylamide Solutions." Advanced Materials Research 361-363 (October 2011): 526–29. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.526.

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In this article, the viscosifying abilities, rheological properties, flow characteristics of pectinate hydrophobically associating polymer (PHAP) solutions with different hydrophobe content were studied using technical methods of viscosity measurement, rheological and core flow experiments. Researches on viscosifying of different PHAPs at 20°C and 65°C in distilled water and saline indicate that, with the raise of hydrophobe content, viscosity of polymer solutions increases first and then decreases, which means that there should be a critical hydrophobe content( CHC). Below CHC, the anti-shear ability of polymer solutions enhances as hydrophobe content rises; while the shear resistance would fall down when and after the content reaches CHC. In high permeability porous media, all polymer solutions take on greater injectivity, and RFF can all be higher than 5, yet with the increasing of hydrophobe content, RF goes up first and then declines. It could be an effective way to enhance mobility control ability, improve polymer flooding effect in high permeability reservoirs and design polymer molecular structure more reasonably, using the pectinate structure and hydrophobic association interaction between polymer moleculars.

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46

Rabin, Y., and H. C. Öttinger. "Dilute Polymer Solutions: Internal Viscosity, Dynamic Scaling, Shear Thinning and Frequency-Dependent Viscosity." Europhysics Letters (EPL) 13, no. 5 (November 1, 1990): 423–28. http://dx.doi.org/10.1209/0295-5075/13/5/008.

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47

Beteta, A., L. Nurmi, L. Rosati, S. Hanski, K. McIver, K. Sorbie, and S. K. Toivonen. "Impact of Acrylate and 2-Acrylamido-Tertiary-Butyl Sulfonic Acid Content on the Enhanced Oil Recovery Performance of Synthetic Polymers." SPE Journal 26, no. 04 (January 26, 2021): 2092–113. http://dx.doi.org/10.2118/200441-pa.

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Summary Polymer flooding is a mature enhanced oil recovery (EOR) technology that has seen increasing interest over the past decade. Copolymers of acrylamide (AMD) and acrylic acid (AA) have been the most prominent chemicals to be applied, whereas sulfonated polymers containing 2-acrylamido-tertiary-butyl sulfonic acid (ATBS) have been used for higher temperature and/or salinity conditions. The objective of this study was to generate guidelines to aid in the selection of appropriate polyacrylamide chemistry for each field case. Our focus was in sandstone fields operating at the upper end of AA-AMD temperature tolerance, where there is a decision as to whether sulfonation is required. The performance of the polymer throughout the whole residence time in the reservoir was considered because the macromolecule can undergo some changes over this period. Several key properties of nine distinct polymer species were investigated. The polymers consisted of AA-AMD copolymers, AMD-ATBS copolymers, and AMD-AA-ATBS terpolymers (up to 15 mol% ATBS). The polymer solutions were studied both in their original state as they would be during the injection (initial viscosity, initial adsorption, and in-situ rheology), as well as in the state in which they are expected to be after the polymer has aged in the reservoir (i.e., in a different state of hydrolysis with corresponding changes in viscosity retention and adsorption after aging for various time periods). We note that the combination of viscosity retention and adsorption during the in-situ aging process has not been typically investigated in previous literature, and this is a key novel feature of this work. Each of the above parameters has an impact on the effectiveness and the economic efficiency of a polymer flooding project. The majority of the work was carried out in seawater (SW) at a temperature of 58°C. Under these conditions, AMD-AA samples showed similar solution viscosity at 5 to 30% AA. When the AA-AMD polymer solutions were aged at elevated temperature, the AA content steadily increased because of hydrolysis reactions. When the AA content was 30 mol% or higher, the viscosity started to decrease, and the adsorption started to increase as the polymer solution was aged further. Thermal stability improved when ATBS was included in the polymer structure. In addition, sulfonated polyacrylamide samples showed constant initial viscosity yields and decreasing initial adsorption with increasing ATBS content. The samples showed that the maximum observed apparent in-situ viscosity increased when the bulk viscosity and relaxation time of the solution increased. The information generated in this study can be used to aid in the selection of the most optimal polyacrylamide chemistry, which may not necessarily be the standard 30% AA and 70% AMD copolymer, for sandstone fields operating with moderate/high salinity brines at the upper end of AA-AMD temperature tolerance.

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48

Mossige, E. J., V. Chandran Suja, M. Islamov, S. F. Wheeler, and Gerald G. Fuller. "Evaporation-induced Rayleigh–Taylor instabilities in polymer solutions." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2174 (June 8, 2020): 20190533. http://dx.doi.org/10.1098/rsta.2019.0533.

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Understanding the mechanics of detrimental convective instabilities in drying polymer solutions is crucial in many applications such as the production of film coatings. It is well known that solvent evaporation in polymer solutions can lead to Rayleigh-Bénard or Marangoni-type instabilities. Here, we reveal another mechanism, namely that evaporation can cause the interface to display Rayleigh–Taylor instabilities due to the build-up of a dense layer at the air–liquid interface. We study experimentally the onset time ( t p ) of the instability as a function of the macroscopic properties of aqueous polymer solutions, which we tune by varying the polymer concentration ( c 0 ), molecular weight and polymer type. In dilute solutions, t p shows two limiting behaviours depending on the polymer diffusivity. For high diffusivity polymers (low molecular weight), the pluming time scales as c 0 − 2 / 3 . This result agrees with previous studies on gravitational instabilities in miscible systems where diffusion stabilizes the system. On the other hand, in low diffusivity polymers the pluming time scales as c 0 − 1 . The stabilizing effect of an effective interfacial tension, similar to those in immiscible systems, explains this strong concentration dependence. Above a critical concentration, c ^ , viscosity delays the growth of the instability, allowing time for diffusion to act as the dominant stabilizing mechanism. This results in t p scaling as ( ν / c 0 ) 2/3 . This article is part of the theme issue ‘Stokes at 200 (Part 1)’.

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49

Agasty, Airit, Agnieszka Wisniewska, Tomasz Kalwarczyk, Kaloian Koynov, and Robert Holyst. "Macroscopic Viscosity of Polymer Solutions from the Nanoscale Analysis." ACS Applied Polymer Materials 3, no. 5 (April 12, 2021): 2813–22. http://dx.doi.org/10.1021/acsapm.1c00348.

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50

TERAMOTO, Akio. "Dynamics of Non-flexible Polymer Solutions: Diffusion and Viscosity." Nihon Reoroji Gakkaishi(Journal of the Society of Rheology, Japan) 25, no. 4 (1997): 239–41. http://dx.doi.org/10.1678/rheology1973.25.4_239.

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