Preparation and application of plugging agent for petroleum drilling

Abstract

The invention discloses preparation and application of a plugging agent for petroleum drilling, and relates to the technical field of petroleum drilling. The silicon rubber, the silicon resin and the wollastonite whisker are blended, the resin and the wollastonite whisker play a role in reinforcing and toughening in the silicon rubber and can be used as a softening material during high-temperature working, and meanwhile, the silicon rubber and the silicon resin can be cemented with a stratum in a high-temperature state, stabilize a well wall and improve the strength of a plugging layer; the preparation method comprises the following steps: preparing imitated hollow fibers in an extrusion deposition printing mode, partially shearing to obtain hollow particles so as to improve the flexibility of the elastomer, densifying the imitated hollow fibers and partial hollow particle materials, and promoting hardening by wollastonite whiskers so as to prepare a rigid filler. The hardened simulated hollow fibers and the asphalt softening particles have the effect of'tie bars', so that the pressure bearing capacity and the high-temperature resistance of the plugging layer are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil drilling, and specifically to the preparation and application of a plugging agent for oil drilling. Background Art

[0002] With the world's energy shifting from conventional oil and gas exploration to unconventional exploration, unconventional oil and gas such as shale gas have received increasing attention. Shale gas refers to dark shale or high-carbon shale rich in organic matter, where organic matter exists in adsorbed and free states in matrix pores and fractures, thus storing and preserving biochemically generated gas, thermally generated gas, or a mixture of both. According to data from the U.S. Energy Information Administration in 2013, the global shale gas content is abundant, approaching 1013 trillion cubic meters. China has the largest shale gas reserves in the world, with an exploration reserve of up to 130 trillion cubic meters and a recoverable reserve of 20 trillion cubic meters.

[0003] Under the background of complex geological conditions and the continuous expansion of shale gas exploitation scale, well leakage has become one of the common wellbore complex situations during the development process. Well leakage may induce complex situations such as a decrease in wellbore pressure, wellbore instability, collapse, and blowout, which not only affect the drilling speed but also cause huge economic losses, and impose more stringent requirements on drilling fluid technology. For shale formations, water-based drilling fluids have the characteristics of low cost, wide application, mature technology, and little reservoir pollution, but their disadvantages mainly include prominent complex problems such as easy hydration swelling and sticking of the drill string. Compared with water-based drilling fluids, oil-based drilling fluids hardly react with water-sensitive formation minerals, have advantages such as strong inhibition, high lubrication coefficient, and good thermal stability, which are beneficial to maintaining wellbore stability and are an important means for drilling various complex formations such as mudstone, shale, and gypsum salt layers. Summary of the Invention

[0004] The purpose of the present invention is to provide the preparation and application of a plugging agent for oil drilling to solve the problems existing in the prior art.

[0005] To solve the above technical problems, the present invention provides the following technical solution: A plugging agent for oil drilling, including the following preparation steps:

[0006] (1) Mix polyvinyl alcohol and deionized water, heat up to 60 - 80 °C, stir at 100 - 200 rpm for 3 h, cool down to 30 - 50 °C, add methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, surfactant, photoinitiator, heat up to 70 - 80 °C, stir at 500 rpm for 6 - 8 h, cool to room temperature, filter, take the solid, wash it with deionized water 3 - 8 times, dry at 50 °C for 8 h, then mix it with methyl vinyl silicone rubber, heat up to 230 - 300 °C, stir at 120 rpm for 20 min, and finally, under a nitrogen atmosphere, perform 3D printing to form a hollow fiber-like structure;

[0007] (2) Shear the hollow fiber imitation to obtain elastic hollow particles with a particle size of 100 μm;

[0008] (3) Dry the hollow fiber imitation and the elastic hollow particles at 60 - 100 °C for 9 h, then keep them at 200 - 400 °C for 1 - 2 h, and finally mix the two to obtain rigid fillers;

[0009] (4) Compound the elastic hollow particles, the rigid fillers, and SOLTEX soft asphalt particles with a particle size of 20 - 100 μm to obtain a plugging agent for oil drilling.

[0010] Furthermore, for the dispersible wollastonite whiskers in step (1): Mix the wollastonite whiskers and a 0.5 wt% KH - 570 aqueous solution, stir at 500 - 1000 rpm for 10 - 30 min, filter, take the solid, wash it with deionized water 3 - 8 times, and dry it at 50 °C for 8 h to obtain.

[0011] Furthermore, the surfactant in step (1) is cetyltrimethylammonium bromide.

[0012] Furthermore, the photoinitiator in step (1) is ethyl 2,4,6 - trimethylbenzoylphosphinate.

[0013] Furthermore, the mass ratio of polyvinyl alcohol, deionized water, methyl methacrylate, butyl acrylate, methylphenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, surfactant, photoinitiator, and methyl vinyl silicone rubber in step (1) is 1:100:5 - 20:20:10 - 30:0.05 - 0.1:0.01:0.001:0.01:20 - 50.

[0014] Furthermore, the process parameters of the 3D printing in step (1): The light source is a UV - LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm 2 .

[0015] Furthermore, the outer diameter of the hollow fiber imitation in step (1) is 100 μm, and the inner diameter is 30 - 70 μm.

[0016] Furthermore, the mass ratio of the hollow fiber imitation and the elastic hollow particles in step (3) is 2:1 - 2.

[0017] Furthermore, the mass ratio of the elastic hollow particles, the rigid fillers, and the SOLTEX soft asphalt particles with a particle size of 20 - 100 μm in step (4) is 8 - 20:6 - 15:4.

[0018] Furthermore, the application of a plugging agent for oil drilling in plugging during the oil drilling process

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The present invention uses a blend of silicone rubber, silicone resin, and wollastonite whiskers to prepare an elastic filling material. The resin plays a bridging effect between the silicone rubber macromolecules, and together with the wollastonite whiskers, it plays a role in reinforcing and toughening. When working at high temperatures, it can act as a softening material, soften the silicone rubber, and then adsorb oil products and swell. At the same time, the silanol groups of both condense with the silanol groups on the rock surface to form siloxane - silicon bonds. The non - ionic groups are adsorbed on the rock surface through hydrogen bonding, and the cationic groups with positive charges are tightly adsorbed to the negatively charged formation rock through electrostatic interaction, and then cement with the formation to stabilize the wellbore and improve the strength of the plugging layer, so that the plugging agent can achieve high - temperature resistance and relatively high mechanical properties. Then, a continuous filament is formed by an extrusion - deposition printing method, and at the same time, a hollow - fiber - like structure is prepared by designing a track. Some are sheared to obtain hollow particles, thereby improving the flexibility of the elastomer and enhancing the plugging performance of the plugging agent. Then, the hollow - fiber - like structure and some of the hollow particle materials are densified. The silica in the wollastonite whiskers can act as a nucleating agent for the silicone resin, promoting the formation of silica in the matrix and then achieving hardening. The hardened hollow particles act as rigid fillers, thus playing a bridging role in the plugging agent and enhancing the plugging effect. The hardened hollow - fiber - like structure and the asphalt softening particles play a "reinforcing" effect at high temperatures, and together with the elastic hollow particles and rigid fillers, they form a relatively stable "strong - chain network" in the micro - crack or pore plugging layer, thereby improving the pressure - bearing capacity and high - temperature resistance of the plugging layer. Detailed implementation manners

[0020] The technical solutions in the embodiments 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 a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0021] In order to more clearly illustrate the method provided by the present invention, the following embodiments are used for detailed description. The test methods for each index of the plugging agent for oil drilling prepared in the following embodiments are as follows:

[0022] Plugging performance: Take the examples and comparative examples of the same size. Use the LHKYDL-3 high-temperature and high-pressure plugging test device, use 30-mesh quartz sand as the evaluation sand bed, simulate the leakage channel, add 25 g of the sample to 500 mL of oil-based drilling fluid and stir evenly, then pour it into the water-loss cylinder of the plugging device, place a movable piston on its upper part, then tighten the cylinder cover for sealing, the temperature of the water-loss cylinder is 150 °C, let it stand for 12 h, use a large-displacement reciprocating pump to inject water for pressurization, control the pressurization speed, increase by 1 MPa every 10 min, increase the pressure to 7 MPa, observe and record the leakage degree at the outlet of the sand bed.

[0023] High temperature resistance: Take the examples and comparative examples of the same size and mix them with an appropriate amount of 0# diesel, let it stand at 150 °C for 6 h, pour out the excess oil, and detect the tensile multiple of the sample.

[0024] Oil absorption: Take the examples and comparative examples of the same size, mix them with an appropriate amount of 0# diesel, let it stand for 6 h, pour out the excess oil, and measure the oil absorption multiple of the sample.

[0025] Example 1

[0026] (1) Mix wollastonite whiskers and 0.5 wt% KH-570 aqueous solution, stir at 500 rpm for 10 min, filter, take the solid, wash it 3 times with deionized water, and dry it at 50 °C for 8 h to obtain dispersive wollastonite whiskers; mix polyvinyl alcohol and deionized water, heat up to 60 °C, stir at 100 rpm for 3 h, cool down to 30 °C, add methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, cetyltrimethylammonium bromide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, heat up to 70 °C, stir at 500 rpm for 6 h, cool to room temperature, filter, take the solid, wash it 3 times with deionized water, dry it at 50 °C for 8 h, and then mix it with methyl vinyl silicone rubber, heat up to 230 °C, stir at 120 rpm for 20 min, and finally carry out 3D printing and molding under a nitrogen atmosphere. Its process parameters: the light source is a UV-LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm 2 , to obtain a hollow fiber imitation, its outer diameter is 100 μm and its inner diameter is 30 μm; the mass ratio of polyvinyl alcohol, deionized water, methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, cetyltrimethylammonium bromide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, and methyl vinyl silicone rubber is 1:100:5:20:10:0.05:0.01:0.001:0.01:20;

[0027] (2) Cut the hollow fiber imitation to obtain elastic hollow particles with a particle size of 100 μm;

[0028] (3) The imitation hollow fibers and elastic hollow particles are dried at 60°C for 9 h respectively, then kept at 200°C for 1 h, and finally the two are mixed to obtain rigid fillers; the mass ratio of the imitation hollow fibers to the elastic hollow particles is 2:1;

[0029] (4) The elastic hollow particles, rigid fillers, and SOLTEX softening asphalt particles with a particle size of 20 μm are compounded to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles, rigid fillers, and SOLTEX softening asphalt particles with a particle size of 20 μm is 8:6:4.

[0030] Example 2

[0031] (1) The wollastonite whiskers and 0.5 wt% KH-570 aqueous solution are mixed and stirred at 800 rpm for 20 min, filtered, the solid is taken, washed 5 times with deionized water, and dried at 50°C for 8 h to obtain dispersible wollastonite whiskers; the polyvinyl alcohol and deionized water are mixed, heated to 70°C, stirred at 150 rpm for 3 h, cooled to 40°C, methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, cetyltrimethylammonium bromide, and 2,4,6-trimethylbenzoylphosphate ethyl ester are added, heated to 75°C, stirred at 500 rpm for 7 h, cooled to room temperature, filtered, the solid is taken, washed 5 times with deionized water, and dried at 50°C for 8 h, and then mixed with methyl vinyl silicone rubber, heated to 270°C, stirred at 120 rpm for 20 min, and finally 3D printing is carried out under a nitrogen atmosphere, and its process parameters: the light source is a UV-LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm 2 , to obtain imitation hollow fibers with an outer diameter of 100 μm and an inner diameter of 50 μm; the mass ratio of the polyvinyl alcohol, deionized water, methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, cetyltrimethylammonium bromide, 2,4,6-trimethylbenzoylphosphate ethyl ester, and methyl vinyl silicone rubber is 1:100:13:20:20:0.08:0.01:0.001:0.01:35;

[0032] (2) The imitation hollow fibers are sheared to obtain elastic hollow particles with a particle size of 100 μm;

[0033] (3) The imitation hollow fibers and elastic hollow particles are dried at 80°C for 9 h respectively, then kept at 300°C for 1.5 h, and finally the two are mixed to obtain rigid fillers; the mass ratio of the imitation hollow fibers to the elastic hollow particles is 2:1.5;

[0034] (4) Mix elastic hollow particles, rigid fillers, and SOLTEX softening asphalt particles with a particle size of 70 μm to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles, rigid fillers, and SOLTEX softening asphalt particles with a particle size of 70 μm is 14:9:4.

[0035] Example 3

[0036] (1) Mix wollastonite whiskers and 0.5 wt% KH-570 aqueous solution, stir at 1000 rpm for 30 min, filter, take the solid, wash it 8 times with deionized water, and dry it at 50 °C for 8 h to obtain dispersive wollastonite whiskers; mix polyvinyl alcohol and deionized water, heat up to 80 °C, stir at 200 rpm for 3 h, cool down to 50 °C, add methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, cetyltrimethylammonium bromide, and 2,4,6-trimethylbenzoylphosphine ethyl ester, heat up to 80 °C, stir at 500 rpm for 8 h, cool to room temperature, filter, take the solid, wash it 8 times with deionized water, and dry it at 50 °C for 8 h. Then mix it with methyl vinyl silicone rubber, heat up to 300 °C, stir at 120 rpm for 20 min, and finally carry out 3D printing and molding under a nitrogen atmosphere. The process parameters are: the light source is a UV-LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm 2 , to obtain imitation hollow fibers with an outer diameter of 100 μm and an inner diameter of 70 μm; the mass ratio of the polyvinyl alcohol, deionized water, methyl methacrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, cetyltrimethylammonium bromide, 2,4,6-trimethylbenzoylphosphine ethyl ester, and methyl vinyl silicone rubber is 1:100:20:20:30:0.1:0.01:0.001:0.01:50;

[0037] (2) Cut the imitation hollow fibers to obtain elastic hollow particles with a particle size of 100 μm;

[0038] (3) Dry the imitation hollow fibers and elastic hollow particles at 100 °C for 9 h respectively, then keep them at 400 °C for 2 h, and finally mix them to obtain rigid fillers; the mass ratio of the imitation hollow fibers to the elastic hollow particles is 2:2;

[0039] (4) Mix elastic hollow particles, rigid fillers, and SOLTEX softening asphalt particles with a particle size of 100 μm to obtain a plugging agent for oil drilling; the mass ratio of the elastic hollow particles, rigid fillers, and SOLTEX softening asphalt particles with a particle size of 100 μm is 20:15:4.

[0040] Comparative Example 1

[0041] The difference between Comparative Example 1 and Example 2 lies in step (1). Modify step (1) as follows: Mix polyvinyl alcohol and deionized water, heat up to 70 °C, stir at 150 rpm for 3 h, cool down to 40 °C, add methyl acrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, cetyltrimethylammonium bromide, and 2,4,6-trimethylbenzoyl diphenylphosphine oxide, heat up to 75 °C, stir at 500 rpm for 7 h, cool down to room temperature, filter, collect the solid, wash it 5 times with deionized water, dry it at 50 °C for 8 h, then mix it with methyl vinyl silicone rubber, heat up to 270 °C, stir at 120 rpm for 20 min, and finally perform 3D printing and molding under a nitrogen atmosphere. The process parameters are: the light source is a UV-LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm 2 , obtaining a hollow fiber imitation with an outer diameter of 100 μm and an inner diameter of 50 μm; the mass ratio of polyvinyl alcohol, deionized water, methyl acrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, cetyltrimethylammonium bromide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, and methyl vinyl silicone rubber is 1:100:13:20:20:0.08:0.001:0.01:35; the remaining steps are the same as those in Example 2.

[0042] Comparative Example 2

[0043] The difference between Comparative Example 2 and Example 2 lies in step (1). Modify step (1) as follows: Mix wollastonite whiskers and a 0.5 wt% KH-570 aqueous solution, stir at 800 rpm for 20 min, filter, collect the solid, wash it 5 times with deionized water, dry it at 50 °C for 8 h to obtain dispersible wollastonite whiskers; mix polyvinyl alcohol and deionized water, heat up to 70 °C, stir at 150 rpm for 3 h, cool down to 40 °C, add methyl acrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, cetyltrimethylammonium bromide, and 2,4,6-trimethylbenzoyl diphenylphosphine oxide, heat up to 75 °C, stir at 500 rpm for 7 h, cool down to room temperature, filter, collect the solid, wash it 5 times with deionized water, dry it at 50 °C for 8 h, and then perform 3D printing and molding under a nitrogen atmosphere. The process parameters are: the light source is a UV-LED lamp, the light source wavelength is 405 nm, and the light intensity is 1.2 mW / cm 2 , obtaining a hollow fiber imitation with an outer diameter of 100 μm and an inner diameter of 50 μm; the mass ratio of polyvinyl alcohol, deionized water, methyl acrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersible wollastonite whiskers, cetyltrimethylammonium bromide, and 2,4,6-trimethylbenzoyl diphenylphosphine oxide is 1:100:13:20:20:0.08:0.01:0.001:0.01; the remaining steps are the same as those in Example 2.

[0044] Comparative Example 3

[0045] The difference between Comparative Example 3 and Example 2 is that step (3) is absent, and step (4) is changed to: compounding elastic hollow particles and SOLTEX softened asphalt particles with a particle size of 70 μm to obtain a lost circulation material for oil drilling; the mass ratio of the elastic hollow particles to the SOLTEX softened asphalt particles with a particle size of 70 μm is 14:4; the remaining steps are the same as those in Example 2.

[0046] Comparative Example 4

[0047] The difference between Comparative Example 4 and Example 2 is that step (4) is different, and step (4) is changed to: compounding elastic hollow particles and rigid fillers to obtain a lost circulation material for oil drilling; the mass ratio of the elastic hollow particles to the rigid fillers is 14:9; the remaining steps are the same as those in Example 2.

[0048] Effect Example

[0049] The following Table 1 gives the performance analysis results of the lost circulation materials for oil drilling using Examples 1 to 3 and Comparative Examples 1 to 4 of the present invention.

[0050] Table 1

[0051] Degree of loss Drawing ratio Oil absorption ratio Example 1 None 5.9 10 Example 2 None 6.7 12 Example 3 None 6.4 11 Comparative example 1 Linear loss 4.1 10 Comparative example 2 Dripping 4.2 7 Comparative example 3 Linear loss 4.5 9 Comparative example 4 Linear loss 4.6 9

[0052] It can be found from the comparison of the experimental results of the examples and comparative examples in Table 1 that the present invention uses the blending of silicone rubber, silicone resin, and wollastonite whiskers to make an elastic filling material. The resin plays a bridging effect between the silicone rubber macromolecules, and together with the wollastonite whiskers, it plays a role in reinforcing and toughening. When working at high temperatures, it can act as a softening material, adsorb oil products, and swell. At the same time, the silanol groups of the two condense with the silanol groups on the rock surface to form siloxane - silicon bonds. The non - ionic groups are adsorbed on the rock surface through hydrogen bonding, and the cationic groups with positive charges are tightly adsorbed on the negatively charged formation rock through electrostatic interaction, and then cement with the formation to improve the strength of the plugging layer. Thus, the lost circulation material achieves high - temperature resistance and high mechanical properties. Then, through the printing method of extrusion deposition, continuous filaments are formed. At the same time, by designing the track, hollow - like fibers are prepared. Some of them are sheared to obtain hollow particles, thereby improving the flexibility of the elastomer and enhancing the plugging property of the lost circulation material. Then, the hollow - like fibers and some of the hollow particle materials are densified. The silica in the wollastonite whiskers can act as a nucleating agent for the silicone resin, promoting the formation of silica in the matrix, and then achieving hardening. As a rigid filler, it plays a bridging role in the lost circulation material, enhancing the plugging effect. The hardened hollow - like fibers and asphalt softened particles play a "reinforcing bar" effect at high temperatures, and together with the elastic hollow particles and rigid fillers, they form a relatively stable "strong force chain network" in the micro - crack or pore plugging layer, thereby improving the pressure - bearing capacity and high - temperature resistance of the plugging layer.

[0053] It is obvious to those skilled in the art that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

Claims

1. A plugging agent for oil drilling, characterized in that, It includes the following preparation steps: (1) Mix polyvinyl alcohol and deionized water, heat up to 60 - 80°C, stir at 100 - 200 rpm for 3 h, cool down to 30 - 50°C, add methyl acrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, surfactant, photoinitiator, heat up to 70 - 80°C, stir at 500 rpm for 6 - 8 h, cool to room temperature, filter, take the solid, wash it with deionized water for 3 - 8 times, dry at 50°C for 8 h, then mix it with methyl vinyl silicone rubber, heat up to 230 - 300°C, stir at 120 rpm for 20 min, and finally carry out 3D printing and molding under a nitrogen atmosphere to obtain the hollow fiber imitation; (2) Shear the hollow fiber imitation to obtain elastic hollow particles with a particle size of 100 μm; (3) Dry the hollow fiber imitation and the elastic hollow particles at 60 - 100°C for 9 h respectively, then keep them at 200 - 400°C for 1 - 2 h, and finally mix the two to obtain the rigid filler; (4) Compound the elastic hollow particles, the rigid filler, and SOLTEX softened asphalt particles with a particle size of 20 - 100 μm to obtain a lost circulation material for oil drilling.

2. The plugging agent for oil drilling according to claim 1, wherein, The dispersive wollastonite whiskers in step (1): Mix wollastonite whiskers and 0.5 wt% KH-570 aqueous solution, stir at 500 - 1000 rpm for 10 - 30 min, filter, take the solid, wash it with deionized water for 3 - 8 times, and dry at 50°C for 8 h to obtain it.

3. The plugging agent for oil drilling according to claim 1, characterized in that, The surfactant in step (1) is cetyltrimethylammonium bromide.

4. The plugging agent for oil drilling according to claim 1, wherein The photoinitiator in step (1) is ethyl 2,4,6-trimethylbenzoylphosphinate.

5. The plugging agent for oil drilling according to claim 1, characterized in that, The mass ratio of polyvinyl alcohol, deionized water, methyl acrylate, butyl acrylate, methyl phenyl silicone resin, methyltrimethoxysilane, dispersive wollastonite whiskers, surfactant, photoinitiator, and methyl vinyl silicone rubber in step (1) is 1:100:5 - 20:20:10 - 30:0.05 - 0.1:0.01:0.001:0.01:20 - 50.

6. A plugging agent for oil drilling according to claim 1, characterized in that, The process parameters of the 3D printing in step (1): The light source is a UV-LED lamp, the wavelength of the light source is 405 nm, and the light intensity is 1.2 mW / cm 2 .

7. The plugging agent for oil drilling according to claim 1, wherein, The outer diameter of the hollow fiber imitation in step (1) is 100 μm, and the inner diameter is 30 - 70 μm.

8. A plugging agent for oil drilling according to claim 1, characterized in that, The mass ratio of the hollow fiber imitation and the elastic hollow particles in step (3) is 2:1 - 2.

9. A plugging agent for oil drilling according to claim 1, characterized in that, The mass ratio of the elastic hollow particles, the rigid filler, and SOLTEX softened asphalt particles with a particle size of 20 - 100 μm in step (4) is 8 - 20:6 - 15:

4.

10. Application of a lost circulation material for oil drilling according to any one of claims 1 - 9 in plugging during oil drilling.