Temperature-sensitive high-temperature resistant suspending stabilizer for oil-based drilling and completion fluid and preparation method thereof

Abstract

This invention provides a temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method. The preparation method includes the following steps: a) mixing dimer acid monomers and acid anhydride monomers, stirring at 80-90°C until fully mixed, and then purging with nitrogen to remove oxygen, obtaining a first mixture; b) adding a dimer fatty amine monomer to the first mixture obtained in step a, stirring evenly, obtaining a second mixture; c) slowly adding polyethylene polyamine to the second mixture obtained in step b, then heating to 130-180°C, stirring and reacting, removing water from the product solution after the reaction, obtaining the product; d) cooling the product obtained in step c to room temperature, thus obtaining the temperature-sensitive high-temperature resistant suspension stabilizer. The beneficial effects of this invention are: the prepared temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids has excellent high-temperature resistance and can effectively enhance the suspension stability of oil-based drilling and completion fluids under high-temperature conditions.

Description

Technical Field

[0001] This invention relates to the field of suspension stabilizers in oilfield chemicals and materials, specifically to a temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method. Background Technology

[0002] Suspension stabilizers play a crucial role in oil-based drilling and completion fluids. Their main function is to ensure that solid particles in the drilling fluid are uniformly suspended, preventing particle sedimentation and thus maintaining the stability and flowability of the drilling fluid. This is essential for improving drilling efficiency and ensuring wellbore stability.

[0003] To address the problem of poor suspension stability of oil-based drilling and completion fluid systems under high-temperature conditions, Ni Xiaoxiao et al. synthesized a modified lithium saponite MLap-1 for oil-based drilling fluids using n-octyltriethoxysilane and lithium saponite in a one-step sol-gel method. This agent, at a dosage of 0.3%, increased the apparent viscosity and dynamic shear force of the emulsion from 12 mPa·s and 0 Pa to 23 mPa·s and 10 Pa, respectively, while also resisting temperatures up to 200℃. Luo Chunzhi et al. synthesized a polyether fatty acid-based high-temperature shearing agent, LQZ, using polyol polyether and dicarboxylic acid as raw materials. Experiments showed that LQZ improved the suspension capacity of oil-based drilling fluids, with a sedimentation factor (SF) of less than 0.520 after 5 days of standing at 190℃, without significantly increasing plastic viscosity. In summary, the various suspension stabilizing materials currently being developed have largely solved the problem of poor suspension stability in oil-based drilling and completion fluids. However, these materials are difficult to function in ultra-high temperature environments above 230°C, and thus cannot meet the operational requirements of ultra-high temperature and ultra-deep well drilling and completion. Summary of the Invention

[0004] The purpose of this invention is to address at least one of the aforementioned deficiencies in the prior art. For example, one objective of this invention is to provide a temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method. The prepared temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids has excellent high-temperature resistance and can effectively enhance the suspension stability of oil-based drilling and completion fluids under high-temperature conditions. It is temperature-sensitive and can effectively maintain high dynamic shear force, initial and final shear, and low shear rate viscosity of drilling fluids at high temperatures, while not significantly increasing the plastic viscosity of drilling fluids at low temperatures.

[0005] To achieve the above objectives, the present invention provides a method for preparing a temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids, comprising the following steps:

[0006] a. Mix the dimer acid monomer and the acid anhydride monomer, stir at 80-90°C until fully mixed, and then pass nitrogen gas to remove oxygen to obtain the first mixture;

[0007] b. Add the dimeric fatty amine monomer to the first mixture obtained in step a, stir until homogeneous, and obtain the second mixture;

[0008] c. Connect the water separator and the condenser, and slowly add polyethylene polyamine dropwise to the second mixture obtained in step b. After the dropwise addition is complete, raise the temperature to 130-180°C, stir the reaction, and react until no water is generated to obtain the product.

[0009] d. Cool the product obtained in step c to room temperature to obtain a temperature-sensitive high-temperature suspension stabilizer.

[0010] In a preferred embodiment of this solution, in step a, the molar ratio of dimer acid monomers to anhydride monomers is 0.9 to 1.1:1.

[0011] In a preferred embodiment of this solution, in step a, the molar ratio of dimer acid monomers to anhydride monomers is 1:1.

[0012] In a preferred embodiment of this scheme, in step b, the molar ratio of the first mixture to the dimeric fatty amine monomer is 0.9 to 1.1:2.

[0013] In a preferred embodiment of this scheme, in step b, the molar ratio of the first mixture to the dimeric fatty amine monomer is 1:2.

[0014] In a preferred embodiment of this solution, the dimeric acid monomer is a dimeric fatty acid.

[0015] In a preferred embodiment of this solution, the molecular structural formula of the dimer fatty acid is:

[0016]

[0017] In a preferred embodiment of this solution, the anhydride monomer is either maleic anhydride or adipic anhydride.

[0018] In a preferred embodiment of this solution, the molecular structure of the maleic anhydride is as follows:

[0019]

[0020] In a preferred embodiment of this solution, the molecular structure of the adipic anhydride is as follows:

[0021]

[0022] In a preferred embodiment of this solution, the molecular structural formula of the dimer fatty amine monomer is:

[0023]

[0024] In a preferred embodiment of this solution, the polyethylene polyamine is either diethylenetriamine or triethylenetetramine.

[0025] In a preferred embodiment of this scheme, the molar ratio of the polyethylene polyamine to the first mixture obtained in step a is 1:3.

[0026] In a preferred embodiment of this solution, the molecular structural formula of the diethylenetriamine is:

[0027]

[0028] In a preferred embodiment of this solution, the molecular structural formula of the triethylenetetramine is:

[0029]

[0030] In a preferred embodiment of this solution, the stirring reaction time in step c is 6-8 hours.

[0031] The present invention also provides a temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids, which is prepared by the method described above, and its molecular structure includes long carbon chains, amide groups and cyclic rigid groups.

[0032] The chemical composition of the temperature-sensitive high-temperature suspension stabilizer consists of a copolymer of dicarboxylic acid monomers, dianhydride monomers, dimerized fatty amines, and polyethylenepolyamines. The molecular structure incorporates various functional groups, including long carbon chains, amide groups, and cyclic rigid groups. The lipophilic long carbon chains and strongly hydrophilic amide groups in the suspension stabilizer's structure allow it to adsorb at the oil-water interface and bind to the surface modifier of solid particles through intermolecular hydrogen bonds, acting as a bridge. This results in higher structural strength in the drilling fluid system, thus enhancing suspension stability.

[0033] Compared with the prior art, the beneficial effects of the present invention include at least one of the following:

[0034] (1) A temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method, wherein a temperature-sensitive high-temperature resistant suspension stabilizer is prepared by using dibasic fatty acid monomers, dianhydride monomers, dimeric fatty amines and polyethylene polyamines as raw materials. The temperature-sensitive high-temperature resistant suspension stabilizer has excellent high-temperature resistance and a temperature resistance of up to 230℃.

[0035] (2) The temperature-sensitive high-temperature suspension stabilizer prepared by the present invention can effectively enhance the suspension stability of oil-based drilling and completion fluids under high temperature conditions.

[0036] (3) The temperature-sensitive high-temperature suspension stabilizer prepared by the present invention has temperature sensitivity. It can effectively maintain the high dynamic shear force, initial and final shear and low shear rate viscosity of drilling fluid at high temperature, while not significantly increasing the plastic viscosity of drilling fluid at low temperature. Attached Figure Description

[0037] The above and other objects and / or features of the present invention will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0038] Figure 1 The diagram shows a comparison of the effect of the temperature-sensitive high-temperature suspension stabilizer prepared according to an exemplary embodiment of the present invention on the settling resistance of the oil-based drilling and completion fluid.

[0039] Figure 2 The diagram shows a comparison of the effect of the temperature-sensitive high-temperature suspension stabilizer prepared according to an exemplary embodiment of the present invention and its preparation method on the settling degree of the oil-based drilling and completion fluid.

[0040] Figure 3 A comparative graph showing the effect of the temperature-sensitive high-temperature suspension stabilizer prepared according to an exemplary embodiment of the present invention on the settling factor of the oil-based drilling and completion fluid is presented. Detailed Implementation

[0041] In the following, the temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method will be described in detail with reference to exemplary embodiments.

[0042] Exemplary Example 1

[0043] A temperature-sensitive, high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method, the preparation method comprising the following steps:

[0044] a. Mix the dimer acid monomer and the acid anhydride monomer, stir at 80-90°C until fully mixed, and then pass nitrogen gas to remove oxygen to obtain the first mixture;

[0045] b. Add the dimeric fatty amine monomer to the first mixture obtained in step a, stir until homogeneous, and obtain the second mixture;

[0046] c. Slowly add polyethylene polyamine dropwise to the second mixture obtained in step b, then heat to 130-180°C, stir the reaction for 6-8 hours, and then remove the water from the product solution to obtain the product;

[0047] d. Cool the product obtained in step c to room temperature to obtain a temperature-sensitive high-temperature suspension stabilizer.

[0048] In this exemplary embodiment, in step a, the molar ratio of dimer acid monomer to anhydride monomer is 0.9 to 1.1:1, for example, the molar ratio of dimer acid monomer to anhydride monomer is 0.95:1 or 1.1:1.

[0049] In this exemplary embodiment, in step b, the molar ratio of the first mixture to the dimer fatty amine monomer is 0.9 to 1.1:2. For example, the molar ratio of the first mixture to the dimer fatty amine monomer is 0.95:2 or 1.1:2.

[0050] In this exemplary embodiment, the dimeric acid monomer is a dimeric fatty acid; the molecular structural formula of the dimeric fatty acid is:

[0051]

[0052] In this exemplary embodiment, the anhydride monomer is either maleic anhydride or adipic anhydride. The molecular structure of the maleic anhydride is as follows:

[0053]

[0054] The molecular structure of the adipic anhydride is as follows:

[0055]

[0056] In this exemplary embodiment, the molecular structural formula of the dimer fatty amine monomer is:

[0057]

[0058] In this exemplary embodiment, the polyethylenepolyamine is either diethylenetriamine or triethylenetetramine. The molecular structural formula of the diethylenetriamine is:

[0059]

[0060] The molecular structural formula of the triethylenetetramine is:

[0061]

[0062] In this exemplary embodiment, the temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids includes long carbon chains, amide groups, and cyclic rigid groups in its molecular structure.

[0063] To better understand the exemplary embodiments described above, further explanation will be provided below with reference to specific examples.

[0064] Example 1

[0065] A temperature-sensitive, high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method, the preparation method comprising the following steps:

[0066] a. Add a certain amount of dimer fatty acid and maleic anhydride to a four-necked flask at a molar ratio of 1:1, add a heating device, a stirring device and a dehydration device, and connect a nitrogen port to purge oxygen with nitrogen. Then stir at 90°C until fully mixed.

[0067] b. Mix the mixture obtained in step a with the dimeric fatty amine at a molar ratio of 1:2 and stir until homogeneous;

[0068] c. Slowly add diethylenetriamine (molar ratio of 1:3 to the mixture obtained in step a) to step b, heat to 150°C, stir the reaction for 6-8 hours, and remove water from the reaction process;

[0069] d. Cool the product from the reaction in step c to room temperature to obtain the temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids.

[0070] Example 2

[0071] A temperature-sensitive, high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids and its preparation method, the preparation method comprising the following steps:

[0072] a. Add a certain amount of dimer fatty acid and adipic anhydride to a four-necked flask at a molar ratio of 1:1, add a heating device, a stirring device and a dehydration device, and connect a nitrogen port to purge oxygen with nitrogen. Then stir at 90°C until fully mixed.

[0073] b. Mix the mixture obtained in step a with the dimeric fatty amine at a molar ratio of 1:2 and stir until homogeneous;

[0074] c. Slowly add a certain amount of diethylenetriamine (molar ratio of 1:3 to the mixture obtained in step a) to step b, heat to 150℃, stir the reaction for 6-8 hours, and remove the water in the reaction process.

[0075] d. Cool the product from the reaction in step c to room temperature to obtain the temperature-sensitive high-temperature suspension stabilizer for oil-based drilling and completion fluids.

[0076] Comparative Example 1

[0077] A suspension stabilizer for oil-based drilling and completion fluids and its preparation method, comprising the following steps:

[0078] a. Add a certain amount of dimer fatty acid and maleic anhydride to a four-necked flask at a molar ratio of 1:1, add a heating device, a stirring device and a dehydration device, and connect a nitrogen port to purge oxygen with nitrogen. Then stir at 90°C until fully mixed.

[0079] b. Mix the mixture obtained in step a with the dimeric fatty amine at a molar ratio of 1:2 and stir until homogeneous;

[0080] c. Slowly add a certain amount of diethylenetriamine (molar ratio of 0.9 to 1.1:3 with the mixture obtained in step a) to step b, heat to 120°C, stir the reaction for 6 to 8 hours, and remove the water in the reaction process;

[0081] d. Cool the product from the reaction in step c to room temperature to obtain a suspension stabilizer for oil-based drilling and completion fluids.

[0082] Comparative Example 2

[0083] A suspension stabilizer for oil-based drilling and completion fluids and its preparation method, the preparation method comprising the following steps:

[0084] a. Add a certain amount of dimer fatty acid and maleic anhydride to a four-necked flask at a molar ratio of 1:1, add a heating device, a stirring device and a dehydration device, and connect a nitrogen port to purge oxygen with nitrogen. Then stir at 90°C until fully mixed.

[0085] b. Mix the mixture obtained in step a with the dimeric fatty amine monomer at a molar ratio of 1:1 and stir until homogeneous;

[0086] c. Slowly add a certain amount of diethylenetriamine (molar ratio of 1:3 to the mixture obtained in step a) to step b, heat to 150℃, stir the reaction for 6-8 hours, and remove the water in the reaction process.

[0087] d. Cool the product from the reaction in step c to room temperature to obtain a suspension stabilizer for oil-based drilling and completion fluids.

[0088] Example Effect Evaluation Method

[0089] 1. Appearance

[0090] The appearance of the embodiment was observed directly under natural light.

[0091] 2. Rheological evaluation of oil-based drilling and completion fluids in the examples

[0092] (1) Formulation and rheological evaluation of oil-based drilling and completion fluids

[0093] Prepare an oil-based drilling and completion fluid (No. 5 white oil + 25% CaCl2 solution (oil-water ratio 85:15) + 2% primary emulsifier + 2% secondary emulsifier + 1% wetting agent + 3% organic clay + 5% CaO + barite), density = 1.6 g / cm³ 3The rheological properties of the drilling fluid (apparent viscosity (AV), plastic viscosity (PV), dynamic shear force (YP), φ6, φ3, initial shear (G'), final shear (G”)) were measured and calculated using a six-speed viscometer. 1% of the example was added to the drilling fluid base, stirred at 12000 r / min for 20 min, and the rheological properties were tested at 80°C. The drilling fluid was then placed in an aging tank and aged in a roller heating furnace at 230°C for 16 h, and the rheological properties were tested at 80°C.

[0094] The specific measurement method is as follows:

[0095] Add the drilling fluid to be tested into the mud cup, and use a six-speed rotational viscometer to test the φ600, φ300, φ200, φ100, φ6, and φ3 of the drilling fluid in sequence.

[0096] Apparent viscosity (AV) is calculated using the following formula:

[0097] AV = 0.5 × φ600;

[0098] Plastic viscosity (PV) is calculated using the following formula:

[0099] PV = φ600 - φ300;

[0100] The dynamic shear force (YP) is calculated using the following formula:

[0101] YP=0.51×(2×φ300-φ600).

[0102] (2) High-temperature and high-pressure rheological evaluation test

[0103] 155 mL of pre-stirred drilling fluid sample was added to the test vessel. The rotor was ensured to rotate freely, and a series of measures were taken to ensure equipment safety and sealing at high temperatures, including but not limited to installing a drop hammer, applying high-temperature lubricating oil, and tightening the threads of the test vessel. Subsequently, the device was placed in a high-temperature, high-pressure rotational viscometer, and the pressure pipeline was fixed and connected to ensure accurate measurement of the rheological parameters of the drilling fluid sample at different rotational speeds (600, 300, 200, 100, 6, 3 r / min) under a series of set temperature (range from 60℃ to 240℃) and pressure conditions. The rheological properties of the drilling fluid were then calculated according to the formula.

[0104] Apparent viscosity (AV) is calculated using the following formula:

[0105] AV = 0.5 × φ600;

[0106] Plastic viscosity (PV) is calculated using the following formula:

[0107] PV = φ600 - φ300;

[0108] The dynamic shear force (YP) is calculated using the following formula:

[0109] YP = 0.5 × (2 × φ300 - φ600).

[0110] 3. Evaluation of the suspension stability of oil-based drilling and completion fluids in the examples

[0111] The prepared oil-based drilling and completion fluid was loaded into an aging tank and placed in a high-temperature roller heating furnace. After being heated at 230°C for 16 hours, it was placed in a high-temperature blast drying oven for 1 day, 3 days, 5 days and 7 days of high-temperature settling at 230°C. After settling, the settling stability of the completion fluid system was evaluated using a needle-type compaction test and a settling factor method.

[0112] ① Needle penetration test for density

[0113] First, the drilling fluid to be tested was subjected to high-speed stirring for 10 minutes to ensure its homogeneity. Then, its density and rheological properties were measured. Next, the sample was placed in an aging tank and subjected to a high-temperature static test in an oven. After the set time, the aging tank was cooled and opened. Using a needle-type settling resistance tester, the settling stability of the aged drilling fluid was tested. The maximum resistance encountered by the probe during its descent at different positions and the stable value after the probe touched the bottom were recorded to evaluate the settling stability of the drilling fluid. It is generally believed that the greater the settling stability and the greater the settling resistance, the worse the suspension stability of the drilling fluid.

[0114] ② Sedimentation factor method

[0115] Use a syringe to take 3cm of oil-based drilling and completion fluid from the top of the mud tank, and take 3cm of oil-based drilling and completion fluid from the bottom drain port of the mud tank. The formula for calculating the sedimentation factor SF is as follows:

[0116]

[0117] The top part represents the density of the oil-based drilling and completion fluid in the top 3cm, and the bottom part represents the density of the oil-based drilling and completion fluid in the bottom 3cm of the mud tank. SF is the sedimentation factor. SF = 0.500 indicates no sedimentation, SF ≤ 0.520 indicates good suspension stability, and SF > 0.530 indicates poor suspension stability.

[0118] Example Effects

[0119] 1. Appearance

[0120] All are brownish-black viscous liquids

[0121] 2. Rheological property evaluation of oil-based drilling and completion fluids in the examples

[0122] Table 1 shows the effect of the examples on the rheological properties of oil-based drilling and completion fluids. It can be seen that Example 1 effectively enhances the shear stress of oil-based drilling and completion fluids. The dynamic shear stress of the base emulsion with 1% Example 1 is 11.5 Pa, G' is 10 Pa, and G” is 13.5 Pa, while the dynamic shear stress of the control group is only 1.5 Pa, G' is only 2.5 Pa, and G” is 4.5 Pa. Simultaneously, Example 1 exhibits good high-temperature resistance. After aging at 230℃ for 16 hours, the rheological properties of the drilling fluid with 1% Example 1 remain stable, demonstrating good suspension and sand-carrying capacity. Example 1 is superior to Example 2.

[0123] Table 1. Effects of Examples on Rheological Properties of Oil-Based Drilling and Completion Fluids

[0124]

[0125] Table 2 shows the effects of the examples on the high-temperature and high-pressure rheological properties of oil-based drilling and completion fluids. It can be seen that Example 1 effectively enhances the high-temperature and high-pressure stability of oil-based drilling and completion fluids. The dynamic shear force and 3 / 6 turn reading of the drilling fluid with 1% of Example 1 continuously decreased before 180°C, and began to rise at 180°C. When it reached 230°C, the dynamic shear force was 11 Pa, and the dynamic-plastic ratio was greater than 0.5 Pa / (mPa·s), exhibiting good rock-carrying performance. In contrast, the dynamic shear force of the blank group drilling fluid was only 3.1 Pa, and the dynamic-plastic ratio was 0.14 Pa / (mPa·s). This is because the suspension stabilizer is temperature-sensitive; its polymer molecules undergo a phase transition at 180°C. The change in the hydrophilic-hydrophobic balance of the polymer before and after the temperature response leads to an "aggregation-dissolution" phase change. The hydrogen bonding between the polymer chains and surrounding water molecules is enhanced, and the oleophilic and hydrophilic groups form a dense spatial network structure with the droplets in the system, causing an increase in viscosity, dynamic shear force, and 3 / 6 turn at high temperatures. Example 1 is superior to Example 2, and Example 1 still has excellent cutting effect under high temperature and high pressure conditions.

[0126] Table 2. Effects of Examples on High-Temperature and High-Pressure Rheological Properties of Oil-Based Drilling and Completion Fluids

[0127]

[0128] 3. Evaluation of the suspension stability of oil-based drilling and completion fluids in the examples

[0129] Figure 1 , Figure 2 The following is an example illustrating the effect of oil-based drilling and completion fluid settling resistance and compaction. Figure 3This study examines the effect of the additives on the settling factor of oil-based drilling and completion fluids. The results show that while the settling resistance and density of both groups of drilling fluids in the examples increased with standing time, the increases were significantly lower than those in the control group and the comparative group. After 7 days of high-temperature standing, the settling resistance of the Example 1 group increased by 72%, while the density increased by only 21%; the settling factor remained below 0.52, indicating good suspension stability. Both groups of drilling fluids in the examples exhibited excellent suspension stability, with Example 1 showing better results than Example 2.

[0130] Although the present invention has been described above in conjunction with exemplary embodiments and accompanying drawings, those skilled in the art should understand that various modifications can be made to the above embodiments without departing from the spirit and scope of the claims.

Claims

1. A method for preparing a temperature-sensitive high-temperature resistant suspension stabilizer for oil-based drilling and completion fluids, characterized in that, Includes the following steps: a. Mix the dimer acid monomer and the acid anhydride monomer, stir at 80-90°C until fully mixed, and then pass nitrogen gas to remove oxygen to obtain the first mixture; b. Add the dimeric fatty amine monomer to the first mixture obtained in step a, stir until homogeneous, and obtain the second mixture; c. Slowly add polyethylene polyamine dropwise to the second mixture obtained in step b. After the addition is complete, heat to 130-180°C and stir the reaction until no more water is generated to obtain the product. d. Cool the product obtained in step c to room temperature to obtain a temperature-sensitive high-temperature suspension stabilizer.

2. The production method according to claim 1, characterized by, In step a, the molar ratio of dimer acid monomers to anhydride monomers is 0.9 to 1.1:

1.

3. The production method according to claim 2, characterized by, In step a, the molar ratio of dimer acid monomers to anhydride monomers is 1:

1.

4. The method of claim 1, wherein, In step b, the molar ratio of the first mixture to the dimer fatty amine monomer is 0.9 to 1.1:

2.

5. The preparation method according to claim 1, characterized in that, In step b, the molar ratio of the first mixture to the dimeric fatty amine monomer is 1:

2.

6. The method of claim 1, wherein, The dimer acid monomers are dimer fatty acids.

7. The production method according to claim 6, wherein The molecular structural formula of the dimer fatty acid is:

8. The method of claim 1, wherein, The anhydride monomers are either maleic anhydride or adipic anhydride.

9. The method of claim 1, wherein, The molecular structural formula of the dimer fatty amine monomer is:

10. The method of claim 1, wherein, The polyethylene polyamine is either diethylenetriamine or triethylenetetramine.

11. The method of claim 1, wherein, The molar ratio of the polyethylene polyamine to the first mixture obtained in step a is 1:

3.

12. The method of claim 1, wherein, In step c, the stirring reaction time is 6-8 hours.

13. A temperature-sensitive, high-temperature resistant suspending stabilizer for oil-based drilling and completion fluids, characterized in that, The product is prepared by any one of claims 1 to 12, and its molecular structure includes a long carbon chain, an amide group, and a cyclic rigid group.

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