An anti-biodegradable hydrophobic sulfonate-based acrylamide copolymer containing 2,4-dichlorophenoxy for enhanced oil recovery

Abstract

We report here a novel anti-biodegradable hydrophobic acrylamide copolymer that was prepared from acrylamide, acrylic acid, sodium 3-(allyloxy)-2-hydroxypropane-1-sulfonate and N-allyl-2-(2,4dichlorophenoxy) acetamide using the 2,2 0 -azobis(2-methylpropionamide) dihydrochloride initiation system. Subsequently, the copolymer was characterized by FT-IR, 1 H NMR, TG-DTG and watersolubility. And the biodegradability test indicated that the copolymer was not deemed to be readily biodegradable via a closed bottle test established by the Organization for Economic Co-operation and Development (OECD 301 D). Meanwhile the copolymer could significantly enhance the viscosity of the aqueous solution in comparison with partially hydrolyzed polyacrylamide. A viscosity retention of 51.9% indicated the result of a dramatic improvement of temperature tolerance. And then the excellent salt resistance, shear resistance, viscoelasticity, long-term stability of the copolymer could be obtained, which provides a good theoretical foundation for the application in enhanced oil recovery. In addition, this copolymer exerted stronger mobility control ability with a resistance factor of 22.1 and a residual resistance factor of 5.0, and superior ability for enhanced oil recovery of 12.9%. Hence, the copolymer has potential application for enhanced oil recovery in high-temperature and high-salinity reservoirs.

Hyper-branched structure—an active carrier for copolymer with surface activity, anti-polyelectrolyte effect and hydrophobic association in enhanced oil recovery

“…6(b), when the concentration of polymer solution is lower than the critical association concentration (CAC), the growth rate of viscosity in HPAM was slightly higher than that in PMAD and h-PMAD, with a linear viscosity-concentration relationship. According to the literature, 35 under CAC the association of hydrophobic groups mainly occurs intra-molecularly, and the contribution to viscosity is far less than the electrostatic repulsion of carboxylate ions from HPAM. However, when the concentrations exceeded CAC, the viscosities of the PMAD and h-PMAD were much higher than that of HPAM, exhibiting a power-law exponential growth.…”

“…Obviously, polymers PMAD and h-PMAD exhibited more solubility at higher conductivity values all the time and a shorter steady time of 80 min and 72 min, respectively, compared to HPAM (90 min), which is due to the presence of the carboxylate ion, and the quaternary ammonium and glycol sulte from MMPES made the molecules more soluble. 35 This theory only conrms why h-PMAD ha a shorter steady time than PMAD, originating from its large number of carboxylate ions.…”

“…In our previous works, we prepared a hydrophobically associating polyacrylamide based on oleic imidazoline and sulfonate, 34 an anti-biodegradable hydrophobic sulfonate-based acrylamide copolymer containing 2,4-dichlorophenoxy, 35 an ɑaminophosphonic acid-modied acrylamide-based hydrophobic-associating copolymer 36 and complexes of hydrophobically modied polymer and surface active imidazoliumbased ionic liquids, 37 which all showed gratifying results in enhanced oil recovery, providing strong evidence for the excellent properties of hydrophobic associations and ionic polymers. Based on these results, we made a new attempt to prepare a comb-shaped polyzwitterion with surface-activity via a Nmaleoyl chitosan modied HPAM, the surface tension decreased with the increase of polymer solution concentration within a certain range, this discovery had a great positive meaning on overcoming the chromatographic separation effect and reducing the oil-water interfacial tension to improve oil recovery, also introduced comb-shaped model in copolymer structure.…”

Self‐assembled acrylamide‐based copolymer/surfactant with high‐temperature resistance for enhanced oil recovery

“…It has been reported that a small population of ionic or nonionic surfactants, such as sodium dodecyl sulfate and poly(vinyl alcohol), show a very strong synergy with various polymers in solution . In our previous work, we made many attempts to modify the structures of polyacrylamides to retain their excellent performance under high‐temperature and high‐salt conditions . The results indicate that polymers containing a rigid aromatic ring on the side chains can provide a π–π stacking point and exhibit outstanding shear stability, but their apparent viscosity retention rates are less than 40% when the temperature rises from 30 to 120 °C .…”

Adsorption behavior of the copolymer AM/DMC/APEG/DMAAC-16 on a carbonate rock and its application for acidizing

“…[4][5][6] Recently, hydrophobic associating polymers have been widely used in oileld applications, such as acidizing treatments, 7,8 drilling and completion uids, and polymer ooding. [9][10][11][12] In oileld applications, the hydrophobic associating polymer is adsorbed on the reservoir for the interaction of the polymer and the reservoir, which may have some effect on the reservoir. The adsorption behavior of hydrophobic associating polymers has attracted signicant attention from many researchers.…”