Preparation of a Hydrophobic-Associating Polymer with Ultra-High Salt Resistance Using Synergistic Effect

Polymer, SRP-2-1, was synthesized by micellar polymerization and characterized by 1H NMR. Salt tolerance and viscoelasticity tests verified that the salt resistance of SRP-2-1 was promoted by the synergistic effects of oxyethylene groups, sulfonate, and hydrophobic chains. It is suggested that the structure of SRP-2-1 became more compact with increasing salinity. Furthermore, a mechanism is proposed as to why SRP-2-1 solution has excellent salt-resistance properties. The experimental results indicate that, because of the good shear resistance properties, the polymer SRP-2-1 could be used as an alternative in many fields, for instance in fracturing fluids, enhanced oil recovery, and sewage treatment.

Download Full-text

Novel Hydrophobic Associating Polymer with Good Salt Tolerance

Polymers ◽

10.3390/polym10080849 ◽

2018 ◽

Vol 10 (8) ◽

pp. 849 ◽

Cited By ~ 15

Author(s):

Jincheng Mao ◽

Hongzhong Tan ◽

Bo Yang ◽

Wenlong Zhang ◽

Xiaojiang Yang ◽

...

Keyword(s):

Salt Tolerance ◽

Metal Ions ◽

Oil Recovery ◽

Apparent Viscosity ◽

Hydration Shell ◽

High Viscosity ◽

Ion Concentration ◽

Sodium Acrylate ◽

Salting Out ◽

Associating Polymer

A hydrophobic associating polymer named DiPHAM (acrylamide/sodium acrylamide-2-methylpropanesulfonic/sodium acrylate/N,N-di-n-dodecylacrylamide) with good salt tolerance was synthesized via photo-initiation polymerization. The critical association concentration (CAC) of DiPHAM was determined by viscosity changes to be 490 mg/L with different DiPHAM concentrations and particle sizes varied under such dynamic conditions. The influences of aqueous metal ions with different charges on its aqueous solution were investigated by measuring apparent viscosity, viscoelasticity, thixotropy, rheology, and particle size, and by SEM observation. The apparent viscosity of the DiPHAM solution was affected by metal ions to some extent, but the viscosity of the polymer can be still maintained at 55 mPa·s under 20 × 104 mg/L NaCl. Divalent metal ions show greater impact on DiPHAM aqueous solutions, but the polymer solutions showed resistance to the changes caused in viscosity, structure, and viscoelasticity by Ca2+ and Mg2+ ions. The salt tolerance of DiPHAM is due to the combination of hydrophobic association, the electrostatic shield, and double layer compression of the hydration shell. Increasing the ion concentration enhances the dehydration and further compresses the hydration shell, making the non-structural viscosity decrease, even “salting out”. Measurements of rheological properties showed that DiPHAM solutions could maintain a relatively high viscosity (0.6%-71 mPa·s/0.3%-50 mPa·s) after 120 min of continuous shearing (170 s−1) at 140 °C. Under high-salinity (5000 mg/L Ca2+/3000 mg/L Mg2+) conditions, the solution with 0.6 wt% DiPHAM still maintained a high viscosity (50 mPa·s/70 mPa·s) after continuously shearing for 120 min at 120 °C and 170 s−1. The good salt tolerance of DiPHAM can lead to a variety of applications, including in fracturing fluids for enhanced oil recovery (EOR) and in sewage treatment.

Download Full-text

Experimental Study on High-Performers Quaternary Copolymer Based on Host–Guest Effect

Polymers ◽

10.3390/polym13172972 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2972

Author(s):

Tao Xu ◽

Jincheng Mao ◽

Yang Zhang ◽

Xiaojiang Yang ◽

Chong Lin ◽

...

Keyword(s):

Experimental Study ◽

Free Radical ◽

Salt Tolerance ◽

Maleic Anhydride ◽

Acrylic Acid ◽

Shear Resistance ◽

Drilling Fluids ◽

Formation Water ◽

Fracturing Fluids ◽

Associative Polymer

A quaternary polymer (HGP) was prepared by the free-radical polymerization of acrylamide, acrylic acid, maleic anhydride functionalized β-cyclodextrin (MAH-β-CD), and N-(3-methacrylamidopropyl)-N, N-dimethylnaphthalen-1-aminium chloride (NAP). It was found that host–guest behavior occurred most effectively at a molar rate of NAP and CD with 1:1, which exhibited better solubility than hydrophobically associative polymer. Moreover, the as-prepared polymer has superior salt tolerance, shear resistance, and viscoelasticity due to host–guest strategy. More importantly, the HGP solution simulates the distribution of formation water in the Bohai SZ1-1 oilfield has good rheological properties at 120 °C. All results show that the proposed polymer could be a competitive candidate in oilfield applications such as fracturing fluids, displacement fluids, and drilling fluids.

Download Full-text

Novel Trends in the Development of Surfactant-Based Hydraulic Fracturing Fluids: A Review

Gels ◽

10.3390/gels7040258 ◽

2021 ◽

Vol 7 (4) ◽

pp. 258

Author(s):

Andrey V. Shibaev ◽

Andrei A. Osiptsov ◽

Olga E. Philippova

Keyword(s):

Hydraulic Fracturing ◽

Oil Recovery ◽

Cost Effective ◽

Polymer Gels ◽

High Viscosity ◽

Salt Resistance ◽

Surfactant Mixtures ◽

Fracturing Fluids ◽

Cost Effective Alternative ◽

Main Components

Viscoelastic surfactants (VES) are amphiphilic molecules which self-assemble into long polymer-like aggregates—wormlike micelles. Such micellar chains form an entangled network, imparting high viscosity and viscoelasticity to aqueous solutions. VES are currently attracting great attention as the main components of clean hydraulic fracturing fluids used for enhanced oil recovery (EOR). Fracturing fluids consist of proppant particles suspended in a viscoelastic medium. They are pumped into a wellbore under high pressure to create fractures, through which the oil can flow into the well. Polymer gels have been used most often for fracturing operations; however, VES solutions are advantageous as they usually require no breakers other than reservoir hydrocarbons to be cleaned from the well. Many attempts have recently been made to improve the viscoelastic properties, temperature, and salt resistance of VES fluids to make them a cost-effective alternative to polymer gels. This review aims at describing the novel concepts and advancements in the fundamental science of VES-based fracturing fluids reported in the last few years, which have not yet been widely industrially implemented, but are significant for prospective future applications. Recent achievements, reviewed in this paper, include the use of oligomeric surfactants, surfactant mixtures, hybrid nanoparticle/VES, or polymer/VES fluids. The advantages and limitations of the different VES fluids are discussed. The fundamental reasons for the different ways of improvement of VES performance for fracturing are described.

Download Full-text

Aqueous hybrids of amino-functionalized nanosilica and acrylamide-based polymer for enhanced oil recovery

RSC Advances ◽

10.1039/c8ra07076h ◽

2018 ◽

Vol 8 (66) ◽

pp. 38056-38064 ◽

Cited By ~ 7

Author(s):

Jie Cao ◽

Tao Song ◽

Yuejun Zhu ◽

Xiujun Wang ◽

Shanshan Wang ◽

...

Keyword(s):

Salt Tolerance ◽

Hybrid Systems ◽

Enhanced Oil Recovery ◽

Oil Recovery ◽

Polymer Hybrid

The amino-functionalized nanosilica/polymer hybrid systems have better salt tolerance and EOR performance than unmodified nanosilica polymer hybrid systems.

Download Full-text

Platinum and cobalt intermetallic nanoparticles confined within MIL-101(Cr) for enhanced selective hydrogenation of the carbonyl bond in α,β-unsaturated aldehydes: synergistic effects of electronically modified Pt sites and Lewis acid sites

Catalysis Science & Technology ◽

10.1039/d0cy02082f ◽

2021 ◽

Author(s):

Muhammad Zahid ◽

Jiang Li ◽

Ahmed Ismail ◽

Francisco Zaera ◽

Yujun Zhu

Keyword(s):

Synergistic Effect ◽

Reduction Method ◽

Synergistic Effects ◽

Acid Sites ◽

Lewis Acid Sites ◽

Unsaturated Aldehydes ◽

Uniform Dispersion ◽

Carbonyl Bond ◽

Method Show ◽

Intermetallic Nanoparticles

PtCo/MIL-101(Cr) with high uniform dispersion Pt–Co IMNs synthesized by a polyol reduction method show higher activity for selective catalytic hydrogenation of α,β-unsaturated aldehydes due to the synergistic effect of PtCo and MIL-101(Cr) support.

Download Full-text

Impact of gamma irradiation pretreatment on biochemical and molecular responses of potato growing under salt stress

Chemical and Biological Technologies in Agriculture ◽

10.1186/s40538-021-00233-8 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Elhamahmy Ali Mohamed ◽

Elsadany Osama ◽

Eid Manal ◽

Abdelazeem Samah ◽

Gerish Salah ◽

...

Keyword(s):

Salt Tolerance ◽

Genetic Marker ◽

Gamma Rays ◽

Salt Resistance ◽

Base Pairs ◽

Potato Genotype ◽

Potato Callus ◽

Primer Sequence ◽

Significant Increment

Abstract Background Previous literatures revealed that gamma rays have an increasing effect on salt tolerance in different plants. In vitro experiment was conducted to study the effect of gamma rays (20 Gray) on salt tolerance of four potato cultivars (Lady Rosetta, Diamante, Gold, and Santana). Results Gamma-treated Santana plantlets were more tolerant to salinity as compared to other cultivars. It showed a significant increment of fresh weight (250% over the untreated). Gamma-treated plantlets of Lady Rosetta, Diamante, and Gold showed higher activity of peroxidase (POD) and polyphenol oxidase (PPO). Isoenzymes analysis showed an absence of POD 3, 4, and 5 in Gold plantlets. The dye of most PODs and PPOs bands were denser (more active) in gamma-treated plantlets of Santana as compared to other cultivars. Both gamma-treated and untreated plantlets showed the absence of PPO1 in Lady Rosetta and Diamante, and PPO 3, 4, and 5 in Gold plantlets. Genetic marker analysis using ISSR with six different primers showed obvious unique negative and positive bands with different base pairs in mutant plantlets as compared to the control, according to primer sequence and potato genotype. The 14A primer was an efficient genetic marker between mutated and unmutated potato genotypes. Santana had a unique fingerprint in the 1430-pb site, which can be a selectable marker for the cultivar. An increment in genetic distance between Gold cultivar and others proved that the mutation was induced because of gamma rays. Conclusion We assume that irradiation of potato callus by 20-Gy gamma rays is an effective process for inducing salt resistance. However, this finding should be verified under field conditions. Graphic Abstract

Download Full-text

Synergistic Effects of 5-Fluorouracil in Combination with Diosmetin in Colorectal Cancer Cells

Biology and Life Sciences Forum ◽

10.3390/ecb2021-10276 ◽

2021 ◽

Vol 7 (1) ◽

pp. 6

Author(s):

Sareh Kamran ◽

Ajantha Sinniah ◽

Mohammed Abdullah Alshawsh

Keyword(s):

Colorectal Cancer ◽

Flow Cytometry ◽

Synergistic Effect ◽

Cancer Cells ◽

Synergistic Effects ◽

Neoadjuvant Treatment ◽

Software Tool ◽

New Combination ◽

Combination Regimen ◽

Colorectal Cancer Cells

Colorectal cancer (CRC) is among the most commonly occurring cancers. The management of CRC includes laparoscopic surgery, radiotherapy, chemotherapies and neoadjuvant treatment. However, conventional chemotherapies have poor impact on combating CRC and are associated with severe toxic effects and high rates of relapse. Therefore, searching for a new combination regimen is a favorable consideration. The aim of this study was to elucidate the synergistic effect of 5-fluorouracil (5-FU) and diosmetin in an in vitro model on colorectal cancer cells. An MTT assay was conducted on HCT-116 cancer cells and they were treated with a concentration gradient of 5-FU and diosmetin individually and in combination. The combination index (CI) and dose reduction index (DRI) were calculated using CompuSyn software. Isobologram analysis and synergism determination were performed using the Combenefit software tool and the synergy score was calculated using the SynergyFinder 2.0 software tool. The apoptotic features of the cells were determined via an AO/PI double staining assay and an annexin V assay using a fluorescent microscope and the flow cytometry technique, respectively. The findings showed that the DRI of 5-FU was three-fold lower in the combination with a CI value of less than one, which indicates that there was a synergistic effect. The AO/PI microscopic results revealed signs of apoptosis and dead cells after 72 h of treatment. Flow cytometry analysis confirmed that the apoptotic effect of the combination was more prominent compared to 5-FU alone. The findings of this study offer a potential strategy for reducing the cytotoxicity and enhancing the efficacy of 5-FU on colorectal cancer cells through a synergistic study model.

Download Full-text