A pressure-bearing epoxy resin plugging material for oil-based drilling fluid

Abstract

The invention discloses a pressure-bearing epoxy resin plugging material for oil-based drilling fluid, belonging to the technical field of oil and gas field drilling. The structure of the pressure-bearing epoxy resin plugging material is a branched type, and the epoxy resin plugging material is prepared by a step-by-step method, and the synthetic raw materials include carboxyl-containing phenolic substances, epichlorohydrin, polybenzene substances containing aldehyde groups and ether bonds, boron carbide, and silane coupling agents. The molar ratio of carboxyl-containing phenolic substances, polybenzene substances containing aldehyde groups and ether bonds, and epichlorohydrin is approximately 1:1:2. The amount of the rigid material boron carbide added is between 10-50g. The compressive strength of the pressure-bearing epoxy resin of the present invention can reach 140-190MPa, and it can be used as a pressure-bearing plugging material in oil-based drilling fluid, reduce the leakage of drilling fluid, and improve formation stability.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas field drilling, and in particular to a pressure-bearing epoxy resin plugging material for oil-based drilling fluid. Background Art

[0002] Well leakage refers to the phenomenon that various working fluids leak from the wellbore into the formation under the action of pressure difference during the oil and gas exploration and development process. It is one of the main problems in the complex underground conditions. If effective measures are not taken in time to solve the well leakage problem, it will cause a series of underground accidents and bring huge economic losses to oilfield production. At present, the oil industry has carried out a lot of research and practice on the problem of well leakage, but due to the complexity of the problem of well leakage, the problem has not been completely solved so far. According to statistics, the economic losses caused by well leakage in the global oil industry each year are as high as hundreds of millions of dollars, so research and exploration to solve the problem of well leakage still needs to be continued.

[0003] At present, various conventional plugging agents and new plugging agents have been used to solve this problem, effectively solving common leakage problems and achieving certain application effects. However, with the increase in high-pressure wells, most plugging materials have poor plugging effects due to their insufficient pressure bearing capacity. In order to better deal with well leakage and improve the safety and efficiency of drilling, it is necessary to further develop plugging materials with better pressure bearing capacity, which can effectively plug the leaking layer, thereby minimizing the impact of well leakage on drilling projects.

[0004] CN115772392 A discloses a polymer oil-based cross-linked curing plugging agent for drilling fluid and a preparation method thereof, which is prepared from the following raw materials: 60%-80% of modified epoxy resin, 15%-30% of curing agent, 1%-5% of curing regulator, and 4%-10% of reinforcing agent; the modified epoxy resin is obtained by mixing a first epoxy resin with a second epoxy resin after modification; the plugging agent can effectively seal the leaking layer and prevent leakage, and the compressive strength is greater than 30MPa, but the compressive strength still has room for improvement.

[0005] Epoxy resin is an important engineering material, and its molecular structure contains benzene rings, ether bonds, hydroxyl groups, epoxy groups and other groups. Among them, the benzene ring gives epoxy resin very good mechanical strength and heat resistance, and the ether bond gives it good chemical resistance, which makes epoxy resin one of the better choices for plugging materials. However, most epoxy resins are made from bisphenol A as raw materials, and the synthesized chain-type epoxy resins have poor mechanical properties and cannot be effectively plugged when used for plugging. In contrast, branched epoxy resins are very different from straight-chain types in molecular structure, which enables branched epoxy resins to effectively improve the mechanical properties of the material, especially in terms of pressure bearing capacity. Adding rigid material boron carbide to the material can further improve the compression resistance of epoxy resin. Summary of the invention

[0006] In view of the problem that most current plugging materials still have poor plugging effects due to their insufficient pressure-bearing capacity, the present invention provides a pressure-bearing epoxy resin plugging material for oil-based drilling fluid. The epoxy resin can effectively improve the mechanical properties of the material, especially the pressure-bearing capacity, and can be used as a pressure-bearing plugging material in oil-based drilling fluid to reduce the leakage of drilling fluid and improve formation stability.

[0007] To achieve the above object, the technical solution of the present invention is: a pressure-bearing epoxy resin plugging material for oil-based drilling fluid. The raw materials of the pressure-bearing epoxy resin plugging material include carboxyl-containing phenolic substances, epichlorohydrin, polybenzene substances containing aldehyde groups and ether bonds, boron carbide, and silane coupling agent, and are prepared by the following steps:

[0008] S1. Weigh carboxyl-containing phenolic substances, tetrabutylammonium bromide, and epichlorohydrin in a three-necked flask, heat to 70-90°C, react for 1-3 hours, and then cool to room temperature. Then add tetrabutylammonium bromide and NaOH aqueous solution, stir and react for 0.5-2 hours at room temperature, and purify to obtain an epoxy-containing substance;

[0009] S2. Put polybenzene substances containing aldehyde groups and ether bonds, a 25% ammonia solution and catalyst iron into an autoclave, introduce hydrogen into the autoclave, stir and react at 130-150° C. for 20-24 hours, and purify to obtain polybenzene substances containing amino groups;

[0010] S3, placing the boron carbide in a vacuum drying oven and drying for 8-12 hours, adding the alcohol aqueous solution into a three-necked flask, stirring and slowly dropping the silane coupling agent, mixing evenly, adding acetic acid solution to adjust the pH to 4-5, accurately weighing the dried boron carbide in a three-necked flask and ultrasonically dispersing it, heating it to 70-80°C for reaction for 3-6 hours, filtering it with suction, and drying it in a vacuum drying oven at 110-130°C for 8-12 hours to obtain boron carbide modified with a silane coupling agent;

[0011] S4. Mix the epoxy-containing substance prepared in S1 and the amino-containing polybenzene substance prepared in S2, raise the temperature to 120-160° C. and react for 3-10 hours to obtain a branched epoxy resin polymer, and then mix the branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 to obtain a pressure-bearing epoxy resin.

[0012] The carboxyl-containing phenolic substance in step S1 is one of 1-hydroxy-4-naphthoic acid, 4-hydroxy-3-benzylmethyl-1-naphthoic acid, and 1-hydroxy-2-propyl-9,10-anthraquinone-4-carboxylic acid.

[0013] The polybenzene substance containing aldehyde groups and ether bonds in step S2 is one of 2-(2-formyl-4,5-dimethoxyphenyl)-3-(3,4-dimethoxyphenyl)-6,7-dimethoxynaphthalene, 3-([1,1′-biphenyl]-4-yloxy)-4,5-dimethoxybenzaldehyde, and 1,1-dimethoxy-3-phenylmethoxy.

[0014] The silane coupling agent is one of γ-aminopropyltriethoxysilane and γ-aminopropyltrimethoxysilane.

[0015] The molar ratio of the carboxyl-containing phenolic substance, the aldehyde- and ether-bond-containing polybenzene substance, and epichlorohydrin is approximately 1:1:2.

[0016] The added amount of the rigid material boron carbide is between 10-50g.

[0017] In the present invention, the monomer material for synthesizing the epoxy resin has a multi-benzene ring structure, which can improve the compression resistance and temperature resistance of the epoxy resin, and the molecules are branched rather than linear when the polymerization reaction occurs.

[0018] The epoxy resin in the present invention contains a large amount of benzene ring structures, which are then compounded with the rigid material, so the formed material has good pressure bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the partial structure of the branched epoxy resin polymer in Example 5. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] 1. Preparation of branched epoxy resin pressure-bearing plugging material:

[0022] Example 1

[0023] (1) Synthesis of epoxy-containing substances

[0024] Weigh 0.1 mol of 1-hydroxy-4-naphthoic acid, 3.22 g of tetrabutylammonium bromide and 0.2 mol of epichlorohydrin in a three-necked flask, heat to 70°C and react for 3 h, then cool to room temperature, add 3.22 g of tetrabutylammonium bromide and 80 mL of NaOH aqueous solution, stir and react at room temperature for 1 h, purify to obtain an epoxy-containing substance.

[0025] (2) Synthesis of amino-containing polybenzenes

[0026] 0.1 mol of 2-(2-formyl-4,5-dimethoxyphenyl)-3-(3,4-dimethoxyphenyl)-6,7-dimethoxynaphthalene, 700 mL of 25% ammonia solution and 0.56 g of catalyst iron were put into an autoclave. After hydrogen was introduced into the autoclave, the reaction was stirred at 130°C for 22 hours and purified to obtain amino-containing polybenzene substances.

[0027] (3) Silane coupling agent modified boron carbide

[0028] The boron carbide was placed in a vacuum drying oven and dried for 8 hours. The alcohol aqueous solution was added into a three-necked flask, stirred and 0.75 g of γ-aminopropyltriethoxysilane was slowly added dropwise. After mixing evenly, acetic acid solution was added to adjust the pH to 4-5. 15 g of the dried boron carbide was accurately weighed and ultrasonically dispersed in a three-necked flask. The temperature was raised to 70°C and reacted for 5 hours. The mixture was filtered and dried in a vacuum drying oven at 110°C for 12 hours to obtain boron carbide modified with a silane coupling agent.

[0029] (4) Preparation of epoxy resin pressure-bearing plugging material

[0030] The epoxy-containing substance prepared in (1) and the amino-containing polyphenyl substance prepared in (2) are mixed, and the temperature is raised to 130° C. to react for 7 hours to obtain a branched epoxy resin polymer. The branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 are then mixed to prepare a pressure-bearing epoxy resin.

[0031] Example 2

[0032] (1) Synthesis of epoxy-containing substances

[0033] Weigh 0.1 mol of 4-hydroxy-3-benzylmethyl-1-naphthoic acid, 3.22 g of tetrabutylammonium bromide and 0.2 mol of epichlorohydrin in a three-necked flask, heat to 80°C and react for 3 h, then cool to room temperature, add 3.22 g of tetrabutylammonium bromide and 80 mL of NaOH aqueous solution, stir and react at room temperature for 2 h, purify to obtain an epoxy-containing substance.

[0034] (2) Synthesis of amino-containing polybenzenes

[0035] 0.1 mol of 3-([1,1′-biphenyl]-4-yloxy)-4,5-dimethoxybenzaldehyde, 700 mL of 25% ammonia solution and 0.56 g of catalyst iron were placed in an autoclave. After hydrogen was introduced into the autoclave, the reaction was stirred at 130°C for 20 hours and purified to obtain amino-containing polybenzene substances.

[0036] (3) Silane coupling agent modified boron carbide

[0037] The boron carbide was placed in a vacuum drying oven and dried for 10 hours. The alcohol aqueous solution was added into a three-necked flask, stirred and 1.15 g of γ-aminopropyltrimethoxysilane was slowly added dropwise. After mixing evenly, acetic acid solution was added to adjust the pH to 4-5. 23 g of the dried boron carbide was accurately weighed and ultrasonically dispersed in a three-necked flask. The temperature was raised to 75°C and reacted for 4 hours. The mixture was filtered and dried in a vacuum drying oven at 120°C for 10 hours to obtain boron carbide modified with a silane coupling agent.

[0038] (4) Preparation of epoxy resin pressure-bearing plugging material

[0039] The epoxy-containing substance prepared in (1) and the amino-containing polyphenyl substance prepared in (2) are mixed, and the temperature is raised to 140° C. to react for 6 hours to obtain a branched epoxy resin polymer. The branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 are then mixed to prepare a pressure-bearing epoxy resin.

[0040] Example 3

[0041] (1) Synthesis of epoxy-containing substances

[0042] Weigh 0.1 mol of 4-hydroxy-3-benzylmethyl-1-naphthoic acid, 3.22 g of tetrabutylammonium bromide and 0.2 mol of epichlorohydrin in a three-necked flask, heat to 90°C and react for 2 h, then cool to room temperature, add 3.22 g of tetrabutylammonium bromide and 80 mL of NaOH aqueous solution, stir and react at room temperature for 2 h, purify to obtain an epoxy-containing substance.

[0043] (2) Synthesis of amino-containing polybenzenes

[0044] 0.1 mol of 3-([1,1′-biphenyl]-4-yloxy)-4,5-dimethoxybenzaldehyde, 700 mL of 25% ammonia solution and 0.56 g of catalyst iron were placed in an autoclave. After hydrogen was introduced into the autoclave, the reaction was stirred at 150°C for 24 hours and purified to obtain amino-containing polybenzene substances.

[0045] (3) Silane coupling agent modified boron carbide

[0046] The boron carbide was placed in a vacuum drying oven and dried for 10 hours. The alcohol aqueous solution was added into a three-necked flask, stirred and 1.55 g of γ-aminopropyltrimethoxysilane was slowly added dropwise. After mixing evenly, acetic acid solution was added to adjust the pH to 4-5. 31 g of the dried boron carbide was accurately weighed and ultrasonically dispersed in a three-necked flask. The temperature was raised to 75°C and reacted for 5 hours. The mixture was filtered and dried in a vacuum drying oven at 120°C for 9 hours to obtain boron carbide modified with a silane coupling agent.

[0047] (4) Preparation of epoxy resin pressure-bearing plugging material

[0048] The epoxy-containing substance prepared in (1) and the amino-containing polyphenyl substance prepared in (2) are mixed, and the temperature is raised to 140° C. to react for 8 hours to obtain a branched epoxy resin polymer. The branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 are then mixed to obtain a pressure-bearing epoxy resin.

[0049] Example 4

[0050] (1) Synthesis of epoxy-containing substances

[0051] Weigh 0.1 mol of 1-hydroxy-2-propyl-9,10-anthraquinone-4-carboxylic acid, 3.22 g of tetrabutylammonium bromide, and 0.2 mol of epichlorohydrin in a three-necked flask, heat to 85°C and react for 2 h, then cool to room temperature, add 3.22 g of tetrabutylammonium bromide and 80 mL of NaOH aqueous solution, stir and react at room temperature for 2 h, and purify to obtain an epoxy-containing substance.

[0052] (2) Synthesis of amino-containing polybenzenes

[0053] 0.1 mol of 2-(2-formyl-4,5-dimethoxyphenyl)-3-(3,4-dimethoxyphenyl)-6,7-dimethoxynaphthalene, 700 mL of 25% ammonia solution and 0.56 g of catalyst iron were put into an autoclave. After hydrogen was introduced into the autoclave, the reaction was stirred at 140°C for 23 hours and purified to obtain amino-containing polybenzene substances.

[0054] (3) Silane coupling agent modified boron carbide

[0055] The boron carbide was placed in a vacuum drying oven and dried for 12 hours. The alcohol aqueous solution was added into a three-necked flask, stirred and 1.95 g of γ-aminopropyltriethoxysilane was slowly added dropwise. After mixing evenly, acetic acid solution was added to adjust the pH to 4-5. 39 g of the dried boron carbide was accurately weighed and ultrasonically dispersed in a three-necked flask. The temperature was raised to 80°C and reacted for 4 hours. The mixture was filtered and dried in a vacuum drying oven at 120°C for 12 hours to obtain boron carbide modified with a silane coupling agent.

[0056] (4) Preparation of epoxy resin pressure-bearing plugging material

[0057] The epoxy-containing substance prepared in (1) and the amino-containing polyphenyl substance prepared in (2) are mixed, and the temperature is raised to 150° C. to react for 5 hours to obtain a branched epoxy resin polymer. The branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 are then mixed to prepare a pressure-bearing epoxy resin.

[0058] Example 5

[0059] (1) Synthesis of epoxy-containing substances

[0060] Weigh 0.1 mol of 1-hydroxy-2-propyl-9,10-anthraquinone-4-carboxylic acid, 3.22 g of tetrabutylammonium bromide and 0.2 mol of epichlorohydrin in a three-necked flask, heat to 90°C and react for 1.5 h, then cool to room temperature, add 3.22 g of tetrabutylammonium bromide and 80 mL of NaOH aqueous solution, stir and react at room temperature for 1.5 h, purify to obtain an epoxy-containing substance.

[0061] (2) Synthesis of amino-containing polybenzenes

[0062] 0.1 mol of 1,1-dimethoxy-3-phenylmethoxy, 700 mL of 25% ammonia solution and 0.56 g of catalyst iron were placed in an autoclave. After hydrogen was introduced into the autoclave, the mixture was stirred and reacted at 140° C. for 20 hours. After purification, amino-containing polybenzene substances were obtained.

[0063] (3) Silane coupling agent modified boron carbide

[0064] The boron carbide was placed in a vacuum drying oven and dried for 12 hours. The alcohol aqueous solution was added into a three-necked flask, stirred and 2.35 g of γ-aminopropyltriethoxysilane was slowly added dropwise. After mixing evenly, acetic acid solution was added to adjust the pH to 4-5. 47 g of the dried boron carbide was accurately weighed and ultrasonically dispersed in a three-necked flask. The temperature was raised to 80°C and reacted for 3 hours. The mixture was filtered and dried in a vacuum drying oven at 130°C for 10 hours to obtain boron carbide modified with a silane coupling agent.

[0065] (4) Preparation of epoxy resin pressure-bearing plugging material

[0066] The epoxy-containing substance prepared in (1) and the amino-containing polyphenyl substance prepared in (2) are mixed, and the temperature is raised to 160° C. to react for 8 hours to obtain a branched epoxy resin polymer. The branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 are then mixed to prepare a pressure-bearing epoxy resin.

[0067] Comparative Example

[0068] 50g of bisphenol A epoxy resin and 10g of polyethylene glycol 200 were added into a variable frequency high-speed mixer and stirred for 30 minutes. Then, 2.5g of curing agent Q-500 dicyandiamide, 0.3g of accelerator SH-A100 and 1.3g of stabilizer were added and stirred at 40°C for 6h to make the mixture evenly dispersed to obtain a bisphenol A epoxy resin plugging material.

[0069] 2. Preparation of oil-based drilling fluid

[0070] The present invention mainly describes the application of pressure-bearing plugging branched epoxy resin with the following specific formula. Based on 340 parts by mass of base oil, the specific formula is: 3# white oil + primary emulsifier HIEMUL + auxiliary emulsifier HICOAT + wetting agent HIWET + organic soil SMGEL + calcium oxide + 20% calcium chloride solution + fluid loss reducer SMFLA-O + barite powder + pressure-bearing epoxy resin plugging material.

[0071] The specific preparation process is as follows: 340mL 3# white oil is added to a 1000mL stirring cup, and then 13g of primary emulsifier HIEMUL, 10g of auxiliary emulsifier HICOAT, and 5g of wetting agent HIWET are added, and stirred at high speed for 20min at 12000r / min, 14g of organic soil SMGEL is added, and stirred at high speed for 10min at 12000r / min, and then 23g of calcium oxide is added, and stirred at high speed for 10min at 12000r / min, and 60mL of calcium chloride aqueous solution (calcium chloride mass percentage concentration 20%) is slowly added, and stirred at high speed for 20min; then 24g of fluid loss reducer SMFLA-O is added and stirred at high speed for 20min, and 870g of barite is added and stirred at high speed for 30min to obtain the base slurry of oil-based drilling fluid. The prepared drilling fluid density is 2g / cm 3 .

[0072] 3. Performance Test

[0073] 1. Test of the compressive performance of pressure-bearing epoxy resin plugging materials

[0074] The final products of Example 1, Example 2, Example 3, Example 4 and Example 5 were sampled for compressive strength test, and three groups of samples were taken for each material. The compression test refers to ASTM D6641, and two strain gauges, one vertical and one horizontal, are pasted on the front and back surfaces of the test piece respectively, so as to obtain the average compressive strain and Poisson's ratio of the two surfaces of the test piece. An Instron 5882 testing machine (range 100kN) is used, and a combined loading compression fixture (CLC) is used to apply a compressive load to the test piece, and the data obtained from the test are averaged. Table 1 shows the compressive strength record table of Example 1, Example 2, Example 3, Example 4, Example 5 and the comparative example.

[0075] From the results shown in Table 1, it can be seen that compared with the bisphenol A epoxy resin with a chain molecular structure, the branched epoxy resin has a better pressure bearing capacity, and as the amount of rigid material particles increases, its pressure resistance also increases.

[0076] Table 1 Epoxy resin compression performance test

[0077]

[0078] 2. Wedge-shaped 2mm-3mm crack plugging test

[0079] Evaluation criteria for plugging cracks: The main considerations for plugging cracks are whether the plugging material can quickly form a dense and effective filling layer in the cracks, whether the filling layer can withstand greater pressure and the cracks will no longer extend, thereby increasing the pressure-bearing capacity of the cracks, and the concentration of rigid particles and the compatibility of the cracks.

[0080] According to the above slurry preparation, 19 parts of the same base slurry were prepared, and 0 parts by weight, 1 part by weight, 4 parts by weight, and 7 parts by weight of Example 1, Example 2, Example 3, Example 4, Example 5, and Comparative Example were added respectively to prepare 19 parts of drilling fluids with different addition amounts of pressure-bearing epoxy resin and bisphenol A epoxy resin plugging materials, and the base slurry without plugging materials was used as a blank experimental group. In order to further illustrate the effect of the pressure-bearing epoxy resin plugging material of the present invention, a wedge plate crack plugging experiment was carried out on the oil-based drilling fluids with different amounts of plugging materials added.

[0081] According to Table 2, after adding plugging material to the base slurry, wedge-shaped 2mm-3mm cracks can be plugged. As the amount of plugging material added increases, the plugging effect improves. The formula with the best plugging effect is: base slurry + 7% Example 5.

[0082] Table 2 Results of wedge-shaped 2mm-3mm crack plugging test

[0083]

[0084]

[0085] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A pressure-bearing epoxy resin plugging material for oil-based drilling fluid, characterized in that: The raw materials of the epoxy resin plugging material are carboxyl-containing phenolic substances, epichlorohydrin, polybenzene substances containing aldehyde groups and ether bonds, boron carbide, and silane coupling agent. The molar ratio of the carboxyl-containing phenolic substances, the polybenzene substances containing aldehyde groups and ether bonds, and epichlorohydrin is 1:1:2, and the epoxy resin plugging material is prepared by the following steps: S1. Weigh carboxyl-containing phenolic substances, tetrabutylammonium bromide, and epichlorohydrin in a three-necked flask, heat to 70-90°C, react for 1-3 hours, and then cool to room temperature. Then add tetrabutylammonium bromide and NaOH aqueous solution, stir and react for 0.5-2 hours at room temperature, and purify to obtain an epoxy-containing substance; S2. Put polybenzene substances containing aldehyde groups and ether bonds, a 25% ammonia solution and catalyst iron into an autoclave, introduce hydrogen into the autoclave, stir and react at 130-150° C. for 20-24 hours, and purify to obtain polybenzene substances containing amino groups; S3, placing the boron carbide in a vacuum drying oven and drying for 8-12 hours, adding the alcohol aqueous solution into a three-necked flask, stirring and slowly dropping the silane coupling agent, mixing evenly, adding acetic acid solution to adjust the pH to 4-5, accurately weighing the dried boron carbide in a three-necked flask and ultrasonically dispersing it, heating it to 70-80°C for reaction for 3-6 hours, filtering it with suction, and drying it in a vacuum drying oven at 110-130°C for 8-12 hours to obtain boron carbide modified with a silane coupling agent; S4, mixing the epoxy-containing substance prepared in S1 and the amino-containing polyphenyl substance prepared in S2, heating to 120-160° C. for reaction for 3-10 hours to obtain a branched epoxy resin polymer, and then mixing the branched epoxy resin polymer and the silane coupling agent-modified boron carbide prepared in S3 to obtain a pressure-bearing epoxy resin; The silane coupling agent is one of gamma-aminopropyltriethoxysilane and gamma-aminopropyltrimethoxysilane; the carboxyl-containing phenolic substance is one of 1-hydroxy-4-naphthoic acid, 4-hydroxy-3-benzylmethyl-1-naphthoic acid and 1-hydroxy-2-propyl-9,10-anthraquinone-4-carboxylic acid; the aldehyde- and ether-bonded polybenzene substance is one of 2-(2-formyl-4,5-dimethoxyphenyl)-3-(3,4-dimethoxyphenyl)-6,7-dimethoxynaphthalene, 3-([1,1′-biphenyl]-4-yloxy)-4,5-dimethoxybenzaldehyde and 1,1-dimethoxy-3-phenylmethoxy; and the amount of the rigid material boron carbide added is 10-50g.

2. The pressure-bearing epoxy resin plugging material according to claim 1, characterized in that The epoxy resin is branched.

3. An oil-based drilling fluid, characterized in that: The pressure-bearing epoxy resin plugging material according to claim 1 is added to the drilling fluid.

4. The oil-based drilling fluid according to claim 3, characterized in that: The drilling fluid comprises the following components: base oil, primary emulsifier, auxiliary emulsifier, wetting agent, organic soil, calcium oxide, water phase, fluid loss reducer, plugging material and weighting agent.

5. The oil-based drilling fluid according to claim 4, characterized in that: The base oil is 3# white oil, the primary emulsifier is HIEMUL, the auxiliary emulsifier is HICOAT, the wetting agent is HIWET, the organic soil is SMGEL, the aqueous phase is 20% calcium chloride solution, the fluid loss additive is SMFLA-O, the plugging material is the pressure-bearing epoxy resin according to claim 1, and the weighting agent is barite powder.

6. The oil-based drilling fluid according to claim 5, characterized in that: The drilling fluid comprises the following components in parts by weight: 340 parts of 3# white oil, 12-13 parts of primary emulsifier HIEMUL, 8-10 parts of auxiliary emulsifier HICOAT, 4-5 parts of wetting agent HIWET, 12-14 parts of organic soil SMGEL, 20-23 parts of calcium oxide, 20-24 parts of fluid loss reducer SMFLA-O, 60 parts of 20% calcium chloride solution, 4-28 parts of pressure-bearing epoxy resin, 660-870 parts of barite powder, and the drilling fluid density is 1.8-2.0 g / cm 3 .

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