Preparation and displacement performance of ternary copolymer (HAPEC)/graphene oxide composites

•A hydrophobic functional monomer (APEC) was synthesized.•Introduction of graphene oxide into polymer solutions and formation of stable fluids.•Coping with high temperature and high salt reservoir conditions for enhanced recovery. How to deal with high temperature and high salt reservoirs is a great challenge in the field of polymers. In this paper, a functional monomer (APEC) was homemade, copolymerized with acrylic acid and acrylamide to form a terpolymer, and solution blended with graphene oxide (GO) to prepare a terpolymer/graphene oxide composite (HAPEC/GO). The optimal ratio HAPEC/GO = 20:1 (GH20) was screened. The synthesized materials were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance hydrogen spectroscopy (1H NMR), and electron microscopy (SEM). The temperature sensitivity, salt resistance, rheology, and aging resistance of GH20 were found to be superior to hydrolyzed polyacrylamide (HPAM), as evaluated by the apparent viscosity of the solution. When tested under simulated water conditions of 90 °C and 1.0 × 105 mg/L total mineralization, the GH20 solution demonstrated a further improvement in recovery, reaching 16.99 % compared to water flooding alone. The final recovery was 7.49 % higher than that of HPAM. The results demonstrate that the composite prepared can be effectively utilized in reservoirs with high temperature and high salt conditions, making it a promising method for enhanced oil recovery.