A polymer oil displacement agent for carbonate fracture-cave type oil reservoirs and a preparation method thereof

Abstract

The application discloses a kind of polymer oil displacement agent for carbonate fractured-vug type reservoir and preparation method thereof, step 1, with acetone and ethanol mixed solution as solvent, N, N-dimethylpropylene diamine, diethyl ether and perfluorinated nonanoic acid are added into acetone-ethanol mixed solution, after complete reaction, chloropropene is added, continue to react, after reaction is finished, solvent is removed by evaporation, to obtain fluorocarbon cation hydrophobic monomer CF-1;Step 2, white oil, emulsifier Span80 and Tween80 with mass ratio of 35-45:1-3:1-2 are mixed uniformly to obtain oil phase;AM, sodium p-styrenesulfonate and fluorocarbon cation hydrophobic monomer CF-1 are dissolved in deionized water, sodium bisulfite is added, and stirred uniformly to obtain aqueous solution;The aqueous solution is added to the oil phase to obtain a uniform emulsion, ammonium persulfate is added, and the polymer oil displacement agent is obtained by reaction. It has higher temperature resistance and salt resistance, and greatly reduces the adsorption of carbonate reservoir on the oil displacement agent.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of crude oil production increase, and relates to a polymer oil displacement agent for carbonate fracture-cave type oil reservoir and a preparation method thereof. BACKGROUND

[0002] Typical carbonate fracture-cave type oil reservoirs in China are mainly concentrated in Tarim oilfield and Tahe oilfield, and the water flooding recovery rate is less than 20%, and the remaining oil is rich, so it is urgent to improve the recovery rate of fracture-cave type oil reservoir. The carbonate fracture-cave type oil reservoir is different from the sandstone reservoir, and is mainly a complex combination of solution cave and fracture, and the scale is complex and variable. The solution cave and large fracture are mainly used, the solution cave scale is large, the connection form is various, the spatial distribution is complex, and the heterogeneity is extremely strong. In addition, the carbonate fracture-cave type oil reservoir is buried deep, and the formation condition is extremely harsh. For example, the fracture-cave type oil reservoir in Tahe is buried super-deep (well depth is greater than 5000m), super-high temperature and high pressure (temperature is higher than 150 degrees, pressure is greater than 60MPa), and the mineralization degree is greater than 20×10 4 mg / L, which seriously restricts the research and development of the oil displacement agent.

[0003] At present, the purpose of studying the oil displacement agent and the displacement method is mainly used for sandstone reservoir, but it has been shown that the oil-wet fracture carbonate oil reservoir has great potential for application of the oil displacement agent to improve the recovery rate. It is assumed that in the fractured reservoir, the oil can be produced by water natural imbibition and oil discharge from the rock matrix into the fracture, and for improving the recovery rate by changing the wettability (becoming mixed wettability / water wet) and promoting the imbibition process, the use of the oil displacement agent is attractive. Especially for carbonate reservoir, different types of oil displacement agents have different application effects. The anionic oil displacement agent has high interfacial activity and good temperature resistance. At present, the industrialized anionic oil displacement agents in China include petroleum sulfonate, alkyl benzene sulfonate and petroleum carboxylate. However, most of the anionic oil displacement agents have poor salt resistance, the carbonate rock has positive charge, the adsorption loss of the anionic oil displacement agent is large, and the organic carboxylate adsorbed on the surface of the carbonate rock cannot be effectively desorbed to change the wettability of the rock. The anionic-nonionic amphoteric oil displacement agent introduces a certain amount of ethylene oxide or propylene oxide to the hydrophilic head group of the anionic oil displacement agent, so that the molecular structure has anionic and nonionic hydrophilic head groups. The temperature resistance and salt resistance depend on the type of anionic group, the type and size of alkoxy chain, the type and size of lipophilic group. Compared with the conventional anionic oil displacement agent, the biggest feature is strong salt resistance and small formation adsorption loss, and especially in the high temperature and high salt carbonate rock reservoir with positive charge, the use effect is more excellent than that of the anionic oil displacement agent. The anionic-nonionic amphoteric oil displacement agent is a kind of oil displacement agent suitable for tertiary oil recovery in carbonate reservoir, and the application in the carbonate rock needs to effectively change the wettability of the carbonate rock and the oil production rate, and requires appropriate lipophilic chain length and alkoxy type and group number.

[0004] The oil displacement agent for tertiary oil recovery of carbonate reservoirs in China is still in a developing stage, and there is no widely applicable oil displacement agent system. To select a suitable oil displacement agent system, the specific reservoir conditions must be analyzed. In view of the high temperature and high salt characteristics of carbonate reservoirs, the selected oil displacement agent should have good temperature resistance and salt tolerance, low adsorption loss, and good interfacial activity. However, the performance of the existing oil displacement agents in these aspects cannot meet the use requirements of carbonate reservoirs. SUMMARY

[0005] The present application aims to overcome the above-mentioned shortcomings of the prior art, and provides a high molecular oil displacement agent for carbonate fracture-cave type reservoirs and a preparation method thereof, which has high temperature resistance and salt tolerance, and greatly reduces the adsorption of the oil displacement agent by carbonate reservoirs.

[0006] To achieve the above-mentioned purposes, the present application adopts the following technical solutions:

[0007] A high molecular oil displacement agent for carbonate fracture-cave type reservoirs, which has the following molecular structure formula:

[0008]

[0009] In the formula, m = 1-3, n = 50-70, and x = 3-5.

[0010] A preparation method of the high molecular oil displacement agent for carbonate fracture-cave type reservoirs, comprising the following steps:

[0011] Step 1: Using an acetone-ethanol mixture as a solvent, N, N-dimethylpropylene diamine, diethyl ether, and perfluorinated nonanoic acid are added to the acetone-ethanol mixture. After complete reaction, chloropropene is added for continuous reaction. After the reaction is completed, the solvent is evaporated to obtain fluorocarbon cationic hydrophobic monomer CF-1.

[0012] The amount of each raw material component is as follows: N, N-dimethylpropylene diamine 2-5 parts by weight, perfluorinated nonanoic acid 9-23 parts by weight, chloropropene 3-8 parts by weight, and solvent 64-86 parts by weight. The solvent includes an acetone-ethanol mixture and diethyl ether.

[0013] Step 2, mix the white oil, emulsifier Span 80 and Tween 80 uniformly to obtain an oil phase, in the oil phase, the mass ratio of the white oil, Span 80 and Tween 80 is 35-45:1-3:1-2; dissolve AM, sodium p-styrenesulfonate and fluorocarbon cation hydrophobic monomer CF-1 in deionized water, add sodium bisulfite, stir uniformly to obtain an aqueous solution, in the aqueous solution, the weight parts of AM is 17-40 weight parts, the weight parts of sodium p-styrenesulfonate is 1-6 weight parts, the weight parts of fluorocarbon cation hydrophobic monomer CF-1 is 11-25 weight parts, the weight parts of water is 20-35 weight parts, and the oil phase is 9-15 weight parts; add the aqueous solution to the oil phase to obtain a uniform emulsion, add ammonium persulfate, and obtain the polymer oil displacement agent after the reaction is completed.

[0014] Preferably, in step 1, the mass ratio of acetone and ethanol in the solvent is mixed.

[0015] Preferably, in step 1, under the protection of inert gas, N, N-dimethylpropylenediamine, diethyl ether and perfluorononanoic acid are added into the acetone-ethanol mixed solution.

[0016] Preferably, in step 1, after N, N-dimethylpropylenediamine, diethyl ether and perfluorononanoic acid are added into the acetone-ethanol mixed solution, the reaction is carried out at a temperature of 25-35℃ for 2-5h, and then the temperature is increased to 65-85℃, and chloropropene is added.

[0017] Preferably, in step 1, after chloropropene is added, the reaction is continued for 3-5h.

[0018] Preferably, in step 2, the aqueous solution is added to the oil phase, and inert gas is introduced to obtain a uniform emulsion.

[0019] Preferably, in step 2, after the uniform emulsion is obtained, the inert gas is introduced, the emulsion is heated to 30-40℃, and ammonium persulfate is added.

[0020] Further, the inert gas is nitrogen.

[0021] Preferably, in step 2, after ammonium persulfate is added, the stirring and constant temperature reaction are carried out for 2-6h.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] The present application provides a synthetic fluorine-containing surfactant polymer oil displacement agent. First, a new fluorine-containing intermediate is synthesized by amidation reaction using an excess of N, N-dimethylpropylene diamine and perfluorinated nonanoic acid, then the intermediate is reacted with chloropropene, the purpose of this step is to introduce a double bond into the fluorine-containing intermediate to obtain fluorocarbon cation monomer CF-1, and finally the final fluorine-containing polymer oil displacement agent product is obtained by terpolymerization. The advantage of this synthesis method is that the molecular weight of the synthesized product is high, the activity of the molecule can be improved by modification and adjustment of specific groups, and the fluorine-containing active groups and anion and cation groups introduced in the main structure can greatly reduce the oil-water interfacial tension, reduce the adsorption of carbonate rock formation, and greatly improve the temperature resistance and salt tolerance of the oil displacement agent. The fluorine-containing polymer oil displacement agent is also a supramolecule, which can effectively increase the viscosity of the solution through anion-cation interaction in the aqueous solution, play a flow channel adjusting role in the oil displacement process, achieve the purpose of profile control and oil displacement, and further improve the oil displacement recovery rate; at the same time, the anion-cation interaction can also greatly reduce the adsorption of carbonate rock reservoir to the oil displacement agent, so that the action distance is farther. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The oil displacement agent prepared for Example 1 of the present application is shown in the infrared spectrum;

[0025] Figure 2 The fracture-cave structure model diagram designed for the typical carbonate fracture-cave structure of the present application is shown in the figure. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0027] It should be noted that the words "front", "back", "left", "right", "up" and "down" used in the following description refer to the directions in the drawings, and the words "in" and "out" refer to the directions towards or away from the geometric center of a particular component.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein only for the purpose of describing specific embodiments and is not intended to limit the present application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] The polymer oil displacement agent for carbonate fracture-cave type oil reservoirs provided by the application is a fluorine-containing polymer surfactant, and the molecular structural formula is as follows:

[0030]

[0031] In the formula, m = 1-3, n = 50-70, and x = 3-5.

[0032] The preparation method of the oil displacement agent comprises the following steps:

[0033] Step 1: synthesis of fluorine-containing monomer

[0034] Under nitrogen protection, N, N-dimethylpropylenediamine, diethyl ether and perfluorinated nonanoic acid are added into the acetone-ethanol mixed solution, and the reaction is carried out at 25-35 DEG C for 2-5 h, then the temperature is increased to 65-85 DEG C, chloropropene is added dropwise, and the reaction is continued for 3-5 h, then the solvent is evaporated to obtain the fluorocarbon cation hydrophobic monomer CF-1; wherein the amount of each component is as follows: N, N-dimethylpropylenediamine 2-5 parts by weight, perfluorinated nonanoic acid 9-23 parts by weight, chloropropene 3-8 parts by weight, and solvent (acetone-ethanol mixed solution, diethyl ether) 64-86 parts by weight; the mass ratio of acetone-ethanol to diethyl ether is 10:1.

[0035] Step 2: white oil, emulsifier Span80 and Tween80 are weighed and uniformly mixed by high-speed stirring to obtain an oil phase, wherein the mass ratio of white oil, Span80 and Tween80 in the oil phase is 35-45:1-3:1-2. AM, sodium p-styrene sulfonate and fluorocarbon cation hydrophobic monomer CF-1 are dissolved in deionized water, sodium bisulfite is added, and stirring is uniformly carried out to obtain an aqueous solution. In the aqueous solution, the amount of each component is as follows: 17-40 parts by weight of AM, 1-6 parts by weight of sodium p-styrene sulfonate, 11-25 parts by weight of fluorocarbon cation hydrophobic monomer CF-1, and 20-35 parts by weight of water. The aqueous solution is added dropwise into 9-15 parts by weight of the oil phase, nitrogen is passed, a uniform emulsion is obtained, the emulsion is heated to 30-40 DEG C, ammonium persulfate is added, stirring is carried out, and constant temperature reaction is carried out for 2-6 h to obtain the polymer oil displacement agent.

[0036] Example 1

[0037] A preparation method of a polymer oil displacement agent for carbonate fracture-cave type oil reservoirs, i.e., a fluorine-containing polymer surfactant

[0038] First step: in a three-necked flask with stirring and condensing device, add N, N- dimethylpropylene diamine 12 g and ether 16.5 g, then add the mixture of acetone and ethanol 148.5 g, slowly add 55 g of perfluorinated nonanoic acid, pass nitrogen, react at 30℃ for 3 h; then increase the temperature to 80℃, drop 18 g of chloroacrylate, continue to react for 4 h, remove the solvent in the system using a rotary evaporator, obtain fluorocarbon cation hydrophobic monomer CF-1.

[0039] Second step: weigh 59 g of white oil and 3 g of Span 80, 1.5 g of Tween 80 emulsifier, mix uniformly on an electromagnetic stirrer at a speed of 1000 r / min for 10 min to obtain an oil phase. Weigh 92 g of AM, 13.7 g of sodium p-styrene sulfonate and 69 g of functional monomer CF-1, add 100 g of deionized water, add 1.5 g of sodium bisulfite, stir uniformly to obtain an aqueous solution; drop the aqueous solution into the oil phase, pass nitrogen to obtain a uniform emulsion; set the reaction temperature to 40℃, pass nitrogen, add 1 g of ammonium persulfate, continue to stir, and react at constant temperature for 6 h to obtain a polymer oil displacement agent.

[0040] The structure of the oil displacement agent prepared in Example 1 is characterized by using a Fourier transform infrared spectrometer, and the infrared spectrum is as shown in Figure 1 . The absorption bands at 2893 cm -1 , 2629 cm -1 are respectively the stretching vibration absorption peaks of methyl and methylene; there is no characteristic peak at 1640 cm -1 , indicating that all the monomers have copolymerized; the characteristic peak at 3035 cm -1 is the stretching vibration of benzene ring unsaturated =C-H, the characteristic peak at 782 cm -1 is caused by the out-of-plane bending of benzene ring hydrogen =C-H, and the characteristic peaks at 1034 cm -1 (-S=O symmetric stretching), 1166 cm -1 (-S=O asymmetric stretching), and 618 cm -1 (S-O stretching) all indicate that sodium p-styrene sulfonate is copolymerized into the structure of the oil displacement agent; the characteristic peak at 1375 cm -1 is the stretching vibration of C-F; the peak at 3473 cm -1 is the stretching vibration absorption peak of N-H single bond, the peak at 1681 cm -1 is the stretching vibration absorption peak of -CONH (amide) C=O, the characteristic peak at 1508 cm -1 is caused by the in-plane bending of -NH, the characteristic peak at 1375 cm -1 is the stretching of C-N. The existence of the above peak values proves that the oil displacement agent prepared in Example 1 has the expected molecular structure.

[0041] The basic performance of the oil displacement agent prepared in Example 1 is tested and shown in Table 1.

[0042] Table 1. Performance test results of the oil displacement agent prepared in Example 1

[0043] No. Item Result 1 Appearance Pale yellow viscous liquid 2 pH value 8.0 3 Surface tension (0.2 wt %), mN / m 21.8 4 Interfacial tension (0.2 wt %), mN / m 0.000421 5 Effective content, % 51

[0044] In the table, the surface tension and interfacial tension are measured by dissolving the oil displacement agent in water to form a 0.2% mass concentration aqueous solution.

[0045] Example 2

[0046] A preparation method of a high-molecular oil displacement agent for carbonate fracture-cavity type oil reservoirs, i.e., a fluorine-containing high-molecular surfactant:

[0047] Step 1: In a three-necked flask with stirring and condensing device, 20 g of N, N-dimethylpropylene diamine and 25.15 g of diethyl ether are added, then 251.5 g of a mixed solution of acetone and ethanol is added, 73.4 g of perfluorinated nonanoic acid is slowly added, nitrogen is introduced, and reaction is carried out at 25℃ for 5 h; then the temperature is raised to 65℃, 30 g of chloropropene is added dropwise, and reaction is continued for 5 h; a rotary evaporator is used to remove the solvent in the system, and fluorocarbon cation hydrophobic monomer CF-1 is obtained.

[0048] Step 2: 40 g of white oil, 2 g of Span 80, and 1 g of Tween 80 emulsifier are weighed and stirred at a speed of 1000 r / min for 10 min on an electromagnetic stirrer to mix uniformly to obtain an oil phase. 41 g of AM, 5.95 g of sodium p-styrenesulfonate, and 30.26 g of functional monomer CF-1 are weighed and added to 44 g of deionized water, 0.5 g of sodium bisulfite is added, and stirring is carried out uniformly to obtain an aqueous solution; the aqueous solution is added dropwise to the oil phase, nitrogen is introduced, and a uniform emulsion is obtained; the reaction temperature is set to 37℃, nitrogen is introduced, 0.7 g of ammonium persulfate is added, stirring is continued, and constant-temperature reaction is carried out for 2 h to obtain a high-molecular oil displacement agent.

[0049] Example 3

[0050] A preparation method of a high-molecular oil displacement agent for carbonate fracture-cavity type oil reservoirs, i.e., a fluorine-containing high-molecular surfactant:

[0051] Step 1: In a three-necked flask with stirring and condensing device, 24.52 g of N, N-dimethylpropylene diamine and 33.49 g of diethyl ether are added, then 334.85 g of a mixed solution of acetone and ethanol is added, 75 g of perfluorinated nonanoic acid is slowly added, nitrogen is introduced, and reaction is carried out at 35℃ for 2 h; then the temperature is raised to 85℃, 32.14 g of chloropropene is added dropwise, and reaction is continued for 3 h; a rotary evaporator is used to remove the solvent in the system, and fluorocarbon cation hydrophobic monomer CF-1 is obtained.

[0052] Second step: 41g white oil and 2.5g Span80, 1.2g Tween80 emulsifier were weighed, stirred at 1000r / min for 10min on an electromagnetic stirrer to mix uniformly, to obtain an oil phase. 39.6g AM, 4.8g sodium p-styrenesulfonate and 30g functional monomer CF-1 were weighed, added to 42.6g deionized water, 0.4g sodium bisulfite was added, stirred uniformly to obtain an aqueous solution; the aqueous solution was added dropwise to the oil phase, nitrogen was passed, a uniform emulsion was obtained; the reaction temperature was set to 30℃, nitrogen was passed, 0.5g ammonium persulfate was added, continuous stirring, constant temperature reaction for 5h, to obtain a polymer oil displacement agent.

[0053] Example 4

[0054] An oil displacement agent (aqueous solution) for carbonate fracture-cave type reservoirs, consisting of the following components by mass percentage: oil displacement agent 0.2%, water 99.8%.

[0055] Among them, the oil displacement agent is the oil displacement agent obtained in Example 1.

[0056] The oil displacement agent (aqueous solution) obtained in this example was tested for performance at 150℃, 200,000 mineralization, and the results are shown in Table 2:

[0057] Table 2, performance test of oil displacement agent obtained in Example 2

[0058]

[0059]

[0060] Example 5

[0061] An oil displacement agent (aqueous solution) for carbonate fracture-cave type reservoirs, consisting of the following components by mass percentage: oil displacement agent 0.3%, water 99.7%.

[0062] Among them, the oil displacement agent is the oil displacement agent obtained in Example 1.

[0063] The oil displacement agent (aqueous solution) obtained in this example was tested for performance at 170℃, 250,000 mineralization, and the results are shown in Table 3.

[0064] Table 3, performance test of oil displacement agent obtained in Example 3

[0065]

[0066]

[0067] Example 6:

[0068] The oil displacement agent (aqueous solution) consists of the following components by mass percentage: oil displacement agent 0.2%, water 99.8%.

[0069] wherein the oil displacement agent is the oil displacement agent obtained in Example 1.

[0070] The oil displacement agent obtained in this example was used in an oil displacement experiment on a fracture-cave structure model designed according to a typical carbonate fracture-cave structure, as shown in Figure 1. Figure 2

[0071] The fracture-cave structure model parameters and water displacement experiment parameters were determined in combination with the actual formation conditions and in accordance with the following similarity criteria.

[0072] Table 4. Similarity criteria and their physical meanings

[0073]

[0074] According to the selected parameters, the initial oil-water distribution was established in the model, the injection and production wells were connected to simulate water injection and production until no oil was produced, the water displacement remaining oil was established, and then the injection and production of the oil displacement agent was simulated again (3 times of injection and production), until no liquid was produced, and the experimental data was recorded. According to the selected parameters, the initial oil-water distribution was established in the model, the injection and production wells were connected to simulate water injection and production (1 injection and 1 production) until no oil was produced, the water displacement remaining oil was established, and then the injection and production of the oil displacement agent was simulated again (1 injection and 1 production), until no liquid was produced, and the experimental data was recorded. The data of the injection and production model and the injection and production model were processed respectively, and the average value was obtained, as shown in Table 5.

[0075] Table 5. Results of fracture-cave model enhanced oil recovery experiment of the oil displacement agent in Example 4

[0076] Item Throughput model Injection-production model Water drive recovery, % 31.38 52.75 Recovery after measures, % 40.63 73.23 Oil displacement EOR, % 9.25 20.48

[0077] Example 7

[0078] The TK84XX well is located at the slope part of the structure, and there is no loss during the drilling process. The amplitude variation rate and the well logging show that the reservoir is developed, and the acid fracturing shows that the fracture is normally extended. Comprehensive analysis shows that the reservoir type is fracture type. Before the oil displacement agent oil displacement measure, the well was injected for 5 rounds, with a cumulative water injection of 7904m 3 , a cumulative liquid production of 1.17x104m 3 , a formation void of 4039m 3 , and an average daily oil increase of each round before the measure operation showed a sharp downward trend.

[0079] The TK84XX well used the oil displacement agent prepared in Example 1 for the 6th-8th round of water injection, with a concentration of 0.2%, a cumulative injection of 5000m 3 of the oil displacement liquid in 3 rounds of water injection, an effective period of 287 days, a cumulative oil production of 5932t, a daily oil increase of 3.6t, a cumulative oil increase of 1033.2t, and a good oil increase effect.

[0080] ​In conclusion, the fluorine-containing polymer oil displacement agent provided by the application has both anion and cation groups, can greatly reduce the oil-water interfacial tension and carbonate rock stratum adsorption, has excellent temperature resistance and salt tolerance, is also a supramolecule, can increase the solution viscosity through anion and cation winding, plays a flow channel adjusting role, can play a profile control and displacement role, and further improves the oil displacement recovery rate.

[0081] It should be noted that the relational terms herein such as first and second and the like are used solely to distinguish one entity or action from another, without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0082] It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the technology should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated by reference for the purpose of the present disclosure. The omission of any aspect of the subject matter disclosed herein does not preclude coverage of that aspect, nor does it relinquish any right to that aspect, whether related or unrelated to any other aspects described herein.

Claims

1. A polymeric oil displacement agent for fractured-vuggy reservoirs in carbonate rocks, characterized in that, Its molecular structure is as follows: In the formula, m = 1 to 3, n = 50 to 70, and x = 3 to 5.

2. A method for preparing a polymeric oil displacement agent for carbonate fracture-vuggy reservoirs based on claim 1, characterized in that, Includes the following steps: Step 1: Using a mixture of acetone and ethanol as a solvent, N,N-dimethylpropylenediamine, diethyl ether and perfluorononanoic acid are added to the acetone-ethanol mixture. After the reaction is complete, allyl chloride is added and the reaction continues. After the reaction is completed, the solvent is evaporated to obtain the fluorocarbon cationic hydrophobic monomer CF-1. The amounts of each raw material component are as follows: N,N-dimethylpropylenediamine 2-5 parts by weight, perfluorononanoic acid 9-23 parts by weight, allyl chloride 3-8 parts by weight, and solvent 64-86 parts by weight, including acetone-ethanol mixture and diethyl ether. Step 2: Mix white oil, emulsifier Span80, and Tween80 evenly to obtain an oil phase. The mass ratio of white oil, Span80, and Tween80 in the oil phase is 35-45:1-3:1-2. Dissolve AM, sodium p-styrene sulfonate, and fluorocarbon cationic hydrophobic monomer CF-1 in deionized water. Add sodium bisulfite and stir evenly to obtain an aqueous solution. In the aqueous solution, AM is 17-40 parts by weight, sodium p-styrene sulfonate is 1-6 parts by weight, fluorocarbon cationic hydrophobic monomer CF-1 is 11-25 parts by weight, water is 20-35 parts by weight, and the amount of oil phase is 9-15 parts by weight. Add the aqueous solution to the oil phase to obtain a uniform emulsion. Add ammonium persulfate. After the reaction is complete, a high molecular weight oil displacement agent is obtained.

3. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 1, acetone and ethanol are mixed in equal mass ratios in the solvent.

4. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 1, under the protection of an inert gas, N,N-dimethylpropylenediamine, diethyl ether, and perfluorononanoic acid are added to an acetone-ethanol mixture.

5. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 1, N,N-dimethylpropylenediamine, diethyl ether, and perfluorononanoic acid are added to an acetone-ethanol mixture and reacted at 25-35°C for 2-5 hours. Then, the temperature is raised to 65-85°C, and allyl chloride is added.

6. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 1, after adding allyl chloride, the reaction continues for 3-5 hours.

7. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 2, the aqueous solution is added to the oil phase, and an inert gas is introduced to obtain a homogeneous emulsion.

8. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 2, after obtaining a uniform emulsion, an inert gas is introduced to heat the emulsion to 30-40°C, and then ammonium persulfate is added.

9. The method for preparing a polymeric flooding agent for carbonate fracture-vuggy reservoirs according to any one of claims 4, 7, and 8, characterized in that, The inert gas used is nitrogen.

10. The method for preparing the polymeric oil displacement agent for carbonate fracture-vuggy reservoirs according to claim 2, characterized in that, In step 2, after adding ammonium persulfate, stir and react at a constant temperature for 2-6 hours.

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