Development of Fracturing Fluids Based on Acrylamide Copolymers and Study of Their Physical and Technological Properties Using the Oscillatory Rheometry Methods

This work studies the rheological properties of aqueous solutions of acrylamide copolymers. The prevailing role of elastic properties over viscous properties in predicting the proppant suspension capacity of the resulting fracturing fluid is shown. Furthermore, the potential of the use of oscillatory rheometry for studying fracturing fluid stability is demonstrated.

Regulation of the stability of kaolin dispersion in the salt media by acrylamide copolymers

As a result of the study of the effect of acrylamide copolymers on the stability of the kaolin salt dispersion, it was shown that the aggregation of solid phase particles and the deposition rate of flocs increases when polymers with different adsorption activity are alternately dosed to a disperse system. The adsorption limit, adsorption capacity and adsorption constant are at maximum for alternate adsorption of anionic polyelectrolyte on a cationic polyelectrolyte layer. High adsorption capacity and interaction energy of polymers with the surface and with each other leads to an improvement in flocculation and to the increase in the deposition rate of the kaolin-salt dispersion by 1.3–1.5 times.

Hydrodynamic and adsorption properties of anionic acrylamide copolymers in water-salt media

Rheological properties and concentration cross-overs of anionic acrylamide copolymers in saline solutions (potassium chloride) were investigated by using capillary viscometer method. Area of non-overlapping coils between the crossover concentration and the concentration of fluctuation mesh formation was determined; it was shown that with increase of salt concentration this area practically disappears, i.e. mass transfer mechanism changes near the crossover concentration. It was shown that at low concentrations of potassium chloride increasing the content of ionic groups of macromolecules leads to reduction in the crossover concentration and increase in the effective volume. It is found that the kaolin adsorption capacity decreases when polymers are adsorbed from saline solution, and the adsorption constant is significantly higher in the presence of salt than in water.

Self-Assembly Supramolecular Systems Based on Guanidinium Salts Modified Hyperbranched Polyamidoamine and Cationic Acrylamide Copolymers

Herein, novel hyperbranched polyamidoamine guanidinium salts (GS-h-PAMAM) and two cationic acrylamide copolymers P(AM-DAC-ABSM) and P(AM-DAC-AMTU) were successfully prepared. Then, self-assembly supramolecular systems were synthesized by directly mixing GS-h-PAMAM with copolymers in aqueous solution, and the mechanism of the self-assembly process was speculated. FT-IR, NMR, and SEM were used for structural confirmation. Furthermore, the excellent solution properties revealed that the supramolecular systems had potential application in clay hydration inhibitors. More importantly, utilizing functionalized hyperbranched polyamidoamine in the synthesis self-assembly supramolecular systems was an effective strategy for expanding their application fields and developing new functional materials, providing a powerful reference for the next study.

Modified acrylamide copolymers based on β-cyclodextrin and twin-tail structures for enhanced oil recovery through host–guest interactions

Two kinds of copolymers with host–guest interaction were synthesized, showing great potential for enhanced oil recovery.