Thermoviscosifying polymers based on polyether prepared from inverse emulsion polymerization

Abstract

Thermoviscosifying polymers are attractive for enhancing oil recovery owing to their exceptional thickening power as temperature increases. However, the polymers reported to date show inadequacies including obligatory high polymer concentration to get the thermothickening ability because of their low molecular weight (MW), and inconvenient post-treatment due to the high viscosity after manufacturing. To overcome these drawbacks, inverse emulsion polymerization was used here for preparing polyether-based thermoviscosifying polymers (TVP-Ps) by grafting acrylic monomers onto triblock copolymers PEO-PPO-PEO. It was found the MW of final products could reach 8 million Daltons, making them thermoviscosifying at 0.2 wt %. The viscosity of polymerized inverse emulsions was as low as 175 mPaÁs, leading to direct dispersing. The TVP-Ps containing Pluronic F127, F108, F68 all exhibited significant thermothickening behaviors in both aqueous solutions and brines, and the critical thermoassociative temperature could be tuned by changing the nature or amount of Pluronics. After aging at 45 8C for 60 days with equal initial viscosity, TVP-Ps shows 21% higher viscosity retention than the reference polymer without Pluronic, PAMA, and preliminary core flooding test demonstrated TVP-Ps can get 2.1% higher incremental oil recovery than PAMA. This work paves a new avenue for scaled-up preparation and potential use of TVP-Ps. potential use of TVP-Ps.

HPAM‐g‐PEOPPO: Rheological modifiers in aqueous media of high temperature and high ionic strength

“…In addition to ionic strength, high temperatures of the reservoirs decrease the viscosity reached by the polymer in the aqueous medium . Thus, it would be interesting to develop HPAM derivatives with the ability to increase viscosity under the severe conditions of the reservoir, such as high temperature and high ionic strength …”

Thermoviscosifying Smart Polymers for Oil and Gas Production: State of the Art

“…A latest core flooding test with equal initial viscosity of TVP and conventional polymer solutions in our laboratory [51] also demonstrated that TVP polymer can increase 2.1 % more oil recovery factor than solution and its counterpart at 45 8C.…”

“…Very recently, our team pushed the MW of such graft polymers to 7.8 10 6 g · mol À1 with inverse polymerization, thus at just 0.2 wt% polymer concentration, the graft polymers exhibit profound thermothickening behavior. [51] In addition, the dissolution time of such polymers can be shortened from more than 2 hours on powder product to less than 10 minutes for the emulsion counterpart.…”

Tunable Viscoelastic Properties of Sodium Polyacrylate Solution via CO2-Responsive Switchable Water

“…Those characteristics allow for great potential applications in fields like food science [4], damping [7], tissue engineering [8], and oil development [9,10]. Over the past few decades, smart viscoelastic fluids that respond reversibly to environmental stimuli, e.g., temperature [11][12][13][14][15], pH [16,17], light [18], and CO 2 [19], to demonstrate tunable rheological properties have drawn extensive attention both from engineers in industry and fundamental theoretical scientists. Among above triggers, CO 2 has garnered considerable interests recently due to its nontoxicity, low cost, high availability, and good biocompatibility [19][20][21][22].…”