▎ 摘　　要

NOVELTY - A nano-tackifier is obtained by modifying the lamellar nano-materials with long chains obtained by polymerizing functional monomer and acrylamide. The long chains comprise ethane-containing structural units (I) or (II). The lamellar nano-materials are chosen from at least one of graphene oxide and montmorillonite. The long chains comprise 20-50 %mass (including 20 and 50) functional monomer. USE - Nano-tackifier used for preparing polymer flooding synergistic agent for preparing polymer flooding system for oil displacement (all claimed). ADVANTAGE - The nano-tackifier produces polymer flooding synergistic agent with increased initial viscosity of the polymer solution, reduced oil-water interfacial tension, water-to-oil mobility ratio, improved oil washing efficiency of polymer flooding and maintains stability of the polymer solution for a long time. DETAILED DESCRIPTION - A nano-tackifier is obtained by modifying the lamellar nano-materials with long chains obtained by polymerizing functional monomer and acrylamide. The long chains comprise ethane-containing structural units of formula (I) or (II). The lamellar nano-materials are chosen from at least one of graphene oxide and montmorillonite. The long chains comprise 20-50 %mass (including 20 and 50) functional monomer. R = C6H5-, -COOH or -SO3Na. INDEPENDENT CLAIMS are included for the following: (1) polymer flooding synergistic agent, which comprises 0.01-0.3 %mass nano-tackifier, 0.03-0.5 %mass dispersing solubilizer, 0.02-0.2 %mass ionic complexing agent, 0.01-0.1 %mass reducing agent, 0.01-0.1 %mass bactericide and balance water. The dispersing solubilizer is chosen from at least one of sodium lauryl sulfate and fatty alcohol polyoxyethylene ether. The ionic complexing agent is chosen from at least one of triethanolamine, EDTA, and sodium tripolyphosphate. The reducing agent is chosen from at least one of thiourea, sodium sulfite, and sodium thiosulfate. The bactericide is chosen from at least one of isothiazolinone and composite bactericide SQ8 (mixture of dithiocyan-based methane, benzalkonium chloride, solvent and surfactant); (2) preparation of polymer flooding synergistic agent, which involves (A) preparing solution (S1) of nano-tackifier, dispersion solubilizer and mineralized water, (B) preparing ionic complexing agent solution (S2), mixing solution (S2) and solution (S1) to obtain solution (S3), (C) preparing the bactericide solution and reducing agent solution, and adding bactericide solution and reducing agent solution to the solution (S3). The mineralized water is simulated mineralized water and/or oil field produced water; (3) polymer flooding system, which comprises polymers and polymer flooding synergistic agent. The polymer is polyacrylamide or hydrophobically associating polymer; and (4) preparation of the polymer flooding system, which involves formulating the polymer and mineralized water into a polymer mother liquor, sealing, curing for 2-24 hours, and mixing with a polymer flooding synergistic agent.