Quaternary Copolymers Research Articles

A new inhibitor of quaternary copolymer against calcium carbonate scaling in high-temperature geothermal fluids

An effective quaternary copolymer inhibitor against calcium carbonate scaling in 120 °C geothermal fluids, with an inhibition ratio of over 95 %, was synthesized through aqueous free radical polymerization of itaconic acid (IA), acrylic acid (AA), hydroxy ethyl methacrylate (HEMA), and sodium allylsulfonate (SAS). The synthesis process involved using ammonium persulfate as an initiator and tert-butanol as the molecular weight regulator. A four-factor, three-level orthogonal experiment was conducted to optimize the synthesis process, resulting in a monomer ratio of m(IA):m(AA) = 1:7, 15 % initiator concentration, a reaction temperature of 90 °C, and a reaction time of 2.5 h. Fourier transform infrared spectroscopy (FT-IR) analysis revealed the presence of carboxyl, sulfonic acid, hydroxyl, and ester groups in the copolymer, while thermogravimetric analysis (TGA) confirmed its thermal stability. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) examinations of calcium carbonate crystals indicated that the copolymer scale inhibitor caused significant damage to the surface morphology and crystal structure. This scaling inhibitor is useful for efficient geothermal energy utilization.

Synthesis and study of the effect of the structure of HPEG-type polycarboxylate plasticizers on the properties of low-strength concrete

Polycarboxylate superplasticizers have been synthesized as copolymers of acrylamide with polyethylene glycol metallyl ether (HPEG), acrylic acid, and 2-hydroxyethylacrylate, with a molecular weight of 25–33 kDa. The copolymers were characterized using GPC and NMR, revealing that during copolymerization, the copolymer includes up to 10 mol.% HPEG 3500 Da. Copolymers at a dosage of 0.12 wt% provide significant retention time of the concrete mix. When considering the same mole ratios of HPEG/(other monomers) in the initial mixture, copolymers containing the carboxylate and hydroxyethyl acrylate group are the most effective. In terms of concrete strength, the use of quaternary copolymers (AA/AM/HPEG/2-HEA) results in a slowdown in strength gain at the ages of 1–3 days, while the strength at the age of 28 days exceeds that of double (AM/HPEG) and triple (AA/AM/HPEG) copolymers.

Synthesis and performance evaluation of a novel zwitterionic quaternary copolymer for enhanced oil‐recovery application

AbstractA novel quaternary copolymer of AA/AM/AOS/C16‐DMAAC was synthesized with acrylic acid (AA), acrylamide (AM), sodium α‐alkenyl‐sulfonate (AOS), and dimethyl‐hexadecyl‐allyl‐ammonium chloride (C16‐DMAAC), using ammonium persulfate and sodium bisulfate (NH4)2S2O8‐NaHSO3) as initiators. The structure of AA/AM/AOS/C16‐DMAAC was characterized using Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. It can be found that the thickening capacity, shearing resistance, temperature‐resistance, salt‐resistance, and emulsification properties of AA/AM/AOS/C16‐DMAAC were superior to those of most widely and cost‐effective partially hydrolyzed polyacrylamide (HPAM) solution at the same concentration. Specifically, the viscosity retention rate of AA/AM/AOS/C16‐DMAAC (3000 mg/L) solution was 86%, which was better than that of HPAM solution (52%) after 30 s of mechanical shearing at 28000 r/min. In addition, the enhanced oil recovery of AA/AM/AOS/C16‐DMAAC solution was 16% at 65 °C, which was about 1.5 times higher than that of HPAM solution (11%). Significantly, successful synthesis of zwitterionic quaternary copolymer emphasizes the importance of a systematic approach to designing appropriate copolymers for enhanced oil recovery.Highlights A novel zwitterionic quaternary copolymer of AA/AM/AOS/C16‐DMAAC was successfully synthesized. The performance on thickening capacity, shearing resistance, temperature‐resistance, salt‐resistance, and emulsification properties of AA/AM/AOS/C16‐DMAAC was superior to that of the most widely used partially hydrolyzed polyacrylamide (HPAM). The enhanced oil recovery of AA/AM/AOS/C16‐DMAAC (16%) was about 1.5 times higher than that of HPAM (11%).

Preparation and Performance Evaluation of Quaternary Copolymer Sand Control Agent

Summary Sand production is a common problem in petroleum extraction, and the development of water-soluble polymer sand control agents is currently a research hotspot. However, this research does not provide details of the chemical structure and lacks discussions on adsorption and sand control mechanisms. Herein, a new water-soluble polymer sand control agent (PAADD) is reported on; it is a copolymer of 2-acrylamido-2-methylpropane sulfonic acid (AMPS), N-(3-dimethylaminopropyl) methacrylamide (DPM), a functional monomer (DAM) containing ketone groups and self-crosslinking properties, and acrylamide (AM). First, the synthesis conditions of PAADD are optimized, and then its sand control mechanism is explored. Experimental results reveal that PAADD can adsorb on the sand surface through electrostatic attraction and hydrogen bonding and change the surface properties of sand particles, which promotes the aggregation of sand particles and permits good sand control ability. In flow experiments, after the injection of PAADD solution (500 mg/L) into a sandpacked model with a permeability of 500 md, the critical sand production rate of the sandpacked model increased more than 100 times and the permeability damage rate (PDR) was 30–40%.

Synthesis and performance evaluation of temperature and salt-resistant organic/inorganic composite copolymers

ABSTRACT Ordinary polymers have poor adaptability in high-temperature and high-salt reservoir environments due to their properties. Organic/inorganic composite copolymer microspheres have the advantages of both of them, which are expected to break through their applicability limitations in such oil reservoirs. Therefore, its preparation and performance have always been of great concern to researchers. In this paper, AM/AMPS/Si-St ternary copolymers were synthesized by precipitation polymerization; then modified nano-silica particles were added to synthesize AM/AMPS/Si-St/g-SiO2 organic/inorganic composite quaternary copolymers. FT-IR and SEM characterized the copolymers to confirm that they were prepared successfully. Experiments were carried out to investigate the concentration and ratio of monomers, which showed that the Weissenberg effect could be avoided. The number of polymer molecules could be stabilized under AM concentration of 12 wt%, AM/AMPS/Si-St ratio of 8:1:1, nano silica of 3.3% and the modification conditions of KH570:SiO2 = 1:1. The experiments of temperature and salt resistance of two copolymers were evaluated and compared were conducted by using viscosity and particle size as parameters. The results showed that quaternary copolymers could increase the viscosity retention rate by about 10% compared with ternary copolymers under high content of Na+ and Mg2+. When the two copolymers were placed at 150°C, the appearance and morphology of the terpolymer changed obviously. Through the SEM image of the quaternary copolymers, it could be seen that although the spherical shape of the microsphere had been gradually lost, no degradation occurred, and the stable time of the modified microspheres had been effectively extended.

Synthesis and Solution Properties Evaluation of AATA Quaternary Copolymer

In this study, temperature-resistant functional monomer (TEPA) and hydrophobically associating salt-resistant monomer (APC) were synthesized, respectively. These functional monomers were polymerized with acrylamide (AM) and acrylic acid (AA) to prepare a temperature-resistant and salt-resistant polyacrylamide oil displacement agent with siloxane groups. The viscosity of quaternary copolymer (AATA) solution was taken as evaluation index, the optimum polymerization conditions were determined by single factor experiment. The structure of AATA was characterized by Fourier-transform Infrared (FTIR), 1H NMR spectroscopy and SEM. The thermal decomposition capability was analyzed by TG. The oil displacement efficiency of AATA was evaluated by core flooding experiment. The results showed that AATA had better oil displacement ability than binary copolymer (AM/AA). The enhanced oil recovery was 19.92% at 60 °C and more than 10% even at 90 °C.

Synthesis of a new high temperature and salt resistant zwitterionic filtrate reducer and its application in water-based drilling fluid

To overcome the negative effects of high temperature and salt pollution on the performance of drilling fluid in deep and ultra-deep wells, it is imperative to develop a high- temperature-and salt-resistant filtrate reducer. A zwitterionic quaternary copolymer (DADN) of N, N-dimethylacrylamide (DMAA), 2-acrylamido-2-methylpropane sulfonic acid (AMPS), diallyl dimethyl ammonium chloride (DMDAAC), and N-vinylcaprolactam (NVCL) was synthesized in an aqueous solution by free radical copolymerization reaction. The composition, structure, and thermal stability of the copolymers were characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H NMR), Gel Permeation Chromatography (GPC), elemental analysis and thermogravimetric analysis (TGA), respectively. Furthermore, the filtration loss reduction performance of DADN was evaluated according to the American Petroleum Institute (API) standard. The mechanisms of filtrate loss reduction and salt resistance were revealed based on the transmission electron microscopy (TEM) analysis, adsorption isotherm and zeta potential analysis for the water-based drilling fluid (WBDF) containing DADN, and the scanning electron microscopy (SEM) analysis, energy-dispersive spectrometry (EDS) analysis and Brunner–Emmet–Teller (BET) analysis for the corresponding filter cake. The results showed that the thermal decomposition of DADN mainly happened over 298 ℃. Meanwhile, DADN exhibited the most outstanding filtration loss reduction ability compared to three commercially filtrate reducers (Driscal D, CMC and PAC-Lv). Specifically, the filtration losses of Driscal D/WBDF, CMC/WBDF and PAC-Lv/WBDF were 18.2, 31.2 and 24.8 mL after hot rolling at 220 °C for 16 h, respectively, while the filtration loss of DADN was only 6.5 mL. It was found that 2% DADN showed excellent filtration loss reduction ability at 220 °C and 15% NaCl. As confirmed by the SEM, EDS and adsorption isotherm results, strong adsorption of DADN on bentonite was obtained even under a high temperature and high-salinity environment. In particular, in the high-salinity environment, a firm “star network” structure formed by bentonite/DADN was observed by TEM, significantly improving the colloidal stability and filter cake compactness of WBDF.

Preparation and Properties of a New Type of Hydrophobically Associating Quaternary Copolymer Hpaf for Fracturing Fluid

Preparation and Properties of a New Type of Hydrophobically Associating Quaternary Copolymer Hpaf for Fracturing Fluid

Synthesis of a Novel Filtrate Reducer and Its Application in Water-Based Drilling Fluid for Ultra-High-Temperature Reservoirs

The high-temperature stability and filtration property controlling of ultra-high-temperature water-based drilling fluids is a worldwide problem. To resolve this problem, a high-temperature-resistant quaternary copolymer (HTRTP) was synthesized based on molecular structure optimization design and monomer optimization. The physical and chemical properties were characterized by infrared spectroscopy, thermal weight, and spectrophotometry, and their temperature and salt resistance was evaluated in different drilling fluids, combined with adsorption, particle size analysis, and stability test. The results show that the thermal stability of HTRTP is very strong, and the initial temperature of thermal decomposition is above 320°C. The salt resistance of HTRTP is more than 162 g/L, and the calcium resistance is more than 5000 mg/L, which is equivalent to the foreign temperature-resistant polymer DCL-a, and is superior to the domestic metal ion viscosity increasing fluid loss agent PMHA-II for drilling fluids. It has excellent high-temperature resistance (245°C) and fluid loss reduction effect in fresh water base mud, fresh water weighted base mud, saturated brine base mud, and composite salt water base mud, which is better than foreign DCL-a (245°C) and domestic PMHA (220°C). The adsorption capacity of HTRTP on clay particles is large and firm, and the adsorption capacity changes little under the change of chemical environment and temperature. Both before and after HTRTP aging (245°C/16 h), the permeability of filter cake can be significantly reduced and its compressibility can be improved. By optimizing the particle size gradation of the drilling fluid and enhancing the colloid stability of the system, HTRTP can improve the filtration building capacity of the drilling fluid and reduce the filtration volume. The development of antithermal polymer provides a key treatment agent for the study of anti-high-temperature-resistant saline-based drilling fluid.

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

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.

Physicochemical Properties and Biological Performance of Polymethacrylate Based Gene Delivery Vector Systems: Influence of Amino Functionalities.

Physicochemical characteristics and biological performance of polyplexes based on two identical copolymers bearing tertiary amino or quaternary ammonium groups are evaluated and compared. Poly(2-(dimethylamino)ethyl methacrylate)-b-poly(oligo(ethylene glycol) methyl ether methacrylate) block copolymer (PDMAEMA-b-POEGMA) is synthesized by reversible addition fragmentation chain transfer polymerization. The tertiary amines of PDMAEMA are converted to quaternary ammonium groups by quaternization with methyl iodide. The two copolymers spontaneously formed well-defined polyplexes with DNA. The size, zeta potential, molar mass, aggregation number, and morphology of the polyplex particles are determined. The parent PDMAEMA-b-POEGMA exhibits larger buffering capacity, whereas the corresponding quaternized copolymer (QPDMAEMA-b-POEGMA) displays stronger binding affinity to DNA, yielding invariably larger in size and molar mass particles bearing greater number of DNA molecules per particle. Experiments revealed that QPDMAEMA-b-POEGMA is more effective in transfecting pEGFP-N1 than the parent copolymer, attributed to the larger size, molar mass, and DNA cargo, as well as to the effective cellular traffic, which dominated over the enhanced ability for endo-lysosomal escape of PDMAEMA-b-POEGMA.

A novel zwitterionic quaternary copolymer as a fluid-loss additive for water-based drilling fluids

ABSTRACT Wellbore instability and formation collapse are crucial issues in the process of well excavation in the oil industry under extreme high temperature conditions. A novel zwitterionic quaternary copolymer (PDANV) of 4-vinylpyridine (VP), N, N-dimethylacrylamide (DMAA), 2-acrylamido-2-methylpropane sulfonic acid, N-vinylcaprolactam (NVCL) was synthesized in aqueous solution by free radical copolymerization reaction. The structure of PDANV was characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1 H NMR), and the results indicated that ideal product are obtained. Thermal stability of PDANV was revealed by thermogravimetric analysis (TGA) and result showed that thermal degradation of PDANV mainly happened over 301°C. Simultaneously, PDANV was prepared to further evaluate its effect on rheological and filtration properties of water-based drilling fluids (WBDFs). The results showed that the fluid loss (FLAPI) of PDANV/WBDFs was only 3.4 mL, 6.0 mL before and after hot rolling at 260°C for 16 h, respectively. Compared with the 19.2% and 57.9% reduction of traditional fluid-loss additives CMC and Driscal, the fluid-loss reduction rate of PDANV/WBDFs was 87.5% in ultra-high temperature environment. Additionally, PDANV performed satisfactorily with great properties in WBDFs even at high concentration of salts and calcium. Therefore, it can be used for applications where the PDANV is subjected to certain harsh environments, such as extreme salinity and ultra-high temperature conditions.

Highly elastic superabsorbent collagen/PVP/PAA/PEO hydrogels crosslinked via e-beam radiation

In this work, highly elastic and superabsorbent hydrogels of collagen-poly(vinyl pyrrolidone) (PVP)-poly(acrylic acid) (PAA)-poly(ethylene oxide) (PEO) quaternary copolymer were obtained using e-beam crosslinking reaction to be used for soft tissue engineering. This study is focused on the evaluation of rheological, swelling and stability properties under different pH media, offering in the same time an insight on the hydrogel network parameters. Rheological studies confirm that collagen/PVP/PAA/PEO hydrogels present solid behaviour similar with that of most soft tissue as human abdominal fat, skin and dermis and even more of breast gland or brain and liver. Hydrogels revealed superabsorbent capacity, both in deionized water and in simulated biological buffers, 1600% and 4000%. The stability and physical form of hydrogels were maintained for more than 50 h in environments that simulate both the pH of the healthy skin and that of an infected wound. The elastic modulus and the parameters of the network structure of hydrogels showed the formation of hydrogel with permanent network.

Synthesis and characterization of a quaternary copolymer retarder for cementing in a long sealing section with large temperature difference

We synthesized a retarder, which has excellent thickening performance in the temperature range of 90–150 °C.

Synthesis and Performance Evaluation of Temperature-controlled Viscous Acid

A temperature-controlled viscous acid thickener was obtained by copolymerizing acrylamide, 2-acrylamido-2-methylpropane sulfonic acid, diallyl dimethyl ammonium chloride, and N-vinyl-2-pyrrolidinone, four monomers by aqueous solution polymerization, the mass ratio of the four monomers was 6: 2: 1: 1, the reaction temperature was 45°C and the reaction time was 6 h. The total mass concentration of the monomer was 25% and the oxidation-reduction system of ammonium persulphate and sodium hydrogen sulfite (mass ratio 1: 1) was used as the initiator, the amount was 0.9% of the total mass of the monomer, and the pH of the reaction solution was 6–8. Selecting glutaric dialdehyde and zirconium(IV) acetylacetonate as cross-linking agents, and compounding the synthesized quaternary copolymer after the mass ratio of the two reagents was 1: 1 to achieve acid temperature control viscous properties, were carried out. At 90°C, the quadripolymer and the cross-linking agent were mixed at a mass ratio of 5: 3, and then cross-linked at 60, 80, and 90°C, respectively, as time increased. The apparent viscosity increased sharply, and the apparent viscosity reached a maximum after 20, 15, and 10 min, and the maximum values were 680, 690, and 750 mPa s, respectively. The reaction of marble with thickening acid (20% hydrochloric acid + 1% thickener) and temperature-controlled viscous acid (20% hydrochloric acid + 1% thickener + 0.6 cross-linking agent) was performed at 90°C. The mass loss of marble was 58 and 42% of that of 20% pure hydrochloric acid, respectively. The performance evaluation results show that the temperature-controlled viscous acid has a good compatibility, and the retarding performance is greatly improved compared with the conventional thickened acid. It has good cross-linking and gel breaking performance under high temperature conditions and is suitable for high temperature formations with temperatures above 90°C. Between its excellent compatibility, it can be selected according to the corresponding formation conditions and construction purposes, and other types of acid working fluid or oilfield additives can be used together to achieve better construction results.

Preparation of VCAP/AMPS/DMDAAC/AM Quaternary Copolymer Filtrate Reducer for Drilling Fluids

It is difficult for existing filtrate reducer to meet oilfield application requirements. Based on the molecular structure design principle of temperature-resistant vinyl copolymer, a quaternary copolymer filtrate reducer has been developed with VCAP, AMPS, DMDAAC and AM as monomers through water solution copolymerization using redox initiation system. The optimum synthesis conditions were as follows: the mole ratio of monomer was VCAP/AMPS/DMDAAC/AM=1:1:1:9, reaction temperature was 70°C, reaction time was 6 h, initiator mass ratio was 0.2% and total monomer mass ratio was 20%. The filtration loss of base slurry with 1wt% optimum synthetic product after aging at 150 °C for 16 h was 5.2 mL.

Chemically Stable, Highly Anion Conductive Polymers Composed of Quinquephenylene and Pendant Ammonium Groups

To evaluate the effect of five consecutive phenylene units on the properties of anion conductive polymer membranes, a series of quaternized copolymers (QP-QAF) composed of quinquephenylene and fluo...

Polymeric nanoparticles-based multi-functional coatings on NiTi alloy with nickel ion release control, cytocompatibility, and antibacterial performance

Photo-cross-linked quaternized copolymer coatings on NiTi alloy show prominent inhibition of nickel ion release and antibacterial properties.

Synthesis, Characterization, and Antimicrobial Properties of Peptides Mimicking Copolymers of Maleic Anhydride and 4-Methyl-1-pentene.

Synthetic amphiphilic copolymers with strong antimicrobial properties mimicking natural antimicrobial peptides were obtained via synthesis of an alternating copolymer of maleic anhydride and 4-methyl-1-pentene. The obtained copolymer was modified by grafting with 3-(dimethylamino)-1-propylamine (DMAPA) and imidized in a one-pot synthesis. The obtained copolymer was modified further to yield polycationic copolymers by means of quaternization with methyl iodide and dodecyl iodide, as well as by being sequentially quaternized with both of them. The antimicrobial properties of obtained copolymers were tested against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Staphylococcus aureus. Both tested quaternized copolymers were more active against the Gram-negative E. coli than against the Gram-positive S. aureus. The copolymer modified with both iodides was best when tested against E. coli and, comparing all three copolymers, also exhibited the best effect against S. aureus. Moreover, it shows (limited) selectivity to differentiate between mammalian cells and bacterial cell walls. Comparing the minimum inhibitory concentration (MIC) of Nisin against the Gram-positive bacteria on the molar basis instead on the weight basis, the difference between the effect of Nisin and the copolymer is significantly lower.

In silico metaheuristic tailoring of quaternary copolymers

Particle swarm optimization has been integrated with the negative factor counting technique and inverse iteration method for efficient tailoring of quaternary low-bandgap copolymers. To analyze the performance of this methodology, model quaternary copolymers have been designed. Various parameters have been carefully selected while devising this methodology for engineering quaternary polymers. In particular, a swarm size of 40 has been chosen as it is found to impart good exploring skills to the algorithm. Also, the fitness function so chosen is found effective for judicious decision making. Verifying the reliability of this approach, quaternary D–A–D copolymers based on cyclopentadienylene, silole and thiophene donors, and dicyanomethylene and carbonyl acceptors respectively have been tailored. Cyclopentadienylene–carbonyl is obtained as the best D–A couple and is found to be highly desirable for designing low-bandgap polymeric skeletons. DOS curves of the investigated copolymers give a similar qualitative picture of the trends in the electronic properties as obtained from the algorithm. Such an in silico approach efficiently returns optimized results worthy of synthetic trials.