Synthesis and Evaluation of a Water‐Soluble Hyperbranched Polymer as Enhanced Oil Recovery Chemical

Abstract

A novel hyperbranched polymer was synthesized using acrylamide (AM), acrylic acid (AA), N ‐vinyl‐2‐pyrrolidone (NVP), and dendrite functional monomer as raw materials by redox initiation system in an aqueous medium. The hyperbranched polymer was characterized by infrared (IR) spectroscopy, 1 H NMR spectroscopy, 13 C NMR spectroscopy, elemental analysis, and scanning electron microscope (SEM). The viscosity retention rate of the hyperbranched polymer was 22.89% higher than that of the AM/AA copolymer (HPAM) at 95°C, and the viscosity retention rate was 8.17%, 12.49%, and 13.68% higher than that of HPAM in 18000 mg/L NaCl, 1800 mg/L CaCl 2 , and 1800 mg/L MgCl 2 ·6H 2 O brine, respectively. The hyperbranched polymer exhibited higher apparent viscosity (25.2 mPa·s versus 8.1 mPa·s) under 500 s −1 shear rate at 80°C. Furthermore, the enhanced oil recovery (EOR) of 1500 mg/L hyperbranched polymer solutions was up to 23.51% by the core flooding test at 80°C.