High-efficiency fracture height control product for offshore fracturing and preparation method thereof

Abstract

The invention discloses an efficient fracture height control product for offshore fracturing and a preparation method thereof. The fracture height control product for offshore fracturing comprises a core layer and a wrapping layer, the core layer is a hollow spherical particle, and the shell layer comprises pore channels; the core layer is prepared from a temperature-sensitive polymer, an inorganic filler, a plasticizer, an anti-hydrolysis agent, an antioxidant and a pore-forming agent; and the wrapping layer is prepared from epoxy resin and a coupling agent. The density of the efficient fracture height control product for offshore fracturing is adjustable, the floating capacity, plugging capacity and pressure bearing capacity of the product are improved, the effectiveness of fracture height control can be guaranteed, and the success rate of fracturing construction is increased.

Description

Technical Field

[0001] This invention relates to the field of high-efficiency controlled fracture products in fracturing technology, and more specifically, to a high-efficiency controlled fracture product for offshore fracturing and its preparation method. Background Technology

[0002] Compared to onshore fracturing, the cost of fracturing a single well at sea is significantly higher. Therefore, effectively controlling the vertical growth of fractures is crucial in offshore fracturing operations. When the target reservoir is thin or the stress difference between the reservoir and the interlayer is low, control measures for the scale of fracturing may not be sufficient to prevent vertical fracture development. Fracturing fractures may penetrate the reservoir or interlayer, developing outside the reservoir. The application of fracturing fluid and proppant in this non-reservoir area contributes nothing to production capacity, and ineffective fracture height results in wasted fracturing materials. If the reservoir is accompanied by edge water and bottom water, fracture penetration can cause a sharp increase in water cut, affecting the effectiveness of fracturing operations and potentially leading to fracturing failure. To ensure the success of fracturing, it is essential to effectively control the fracture height, keeping it near the target layer.

[0003] High-strength fracturing proppant products are divided into sinking agents and buoyancy agents. Sinking agents are mostly conventional, mature products such as quartz sand and ceramsite. Research on the application of buoyancy agents is relatively limited. Currently, products made of glass materials such as hollow micropowder, glass microspheres, and cenospheres, as well as ultra-low-density proppant products such as hollow proppants, porous proppants, low-density material proppants, and self-suspended proppants, are available. However, the density of glass proppant products is difficult to control, resulting in poor performance under complex reservoir conditions. Hollow proppants, porous proppants, and low-density material proppants generally have low strength, leading to poor pressure-bearing capacity in the formation of interlayers. Self-suspended proppants, on the other hand, have difficulty in density control and poor buoyancy in viscous fracturing fluids. Therefore, developing a high-strength fracturing proppant for offshore fracturing with controllable density, strong buoyancy, sealing, and pressure-bearing capacity is of significant research importance. Summary of the Invention

[0004] To overcome the shortcomings of existing high-efficiency fracture control products for offshore fracturing, the present invention aims to provide a high-efficiency fracture control product for offshore fracturing and its preparation method. The product uses a mixture of temperature-sensitive polymer, inorganic filler, and other additives as the inner layer, and pre-cured resin as the surface layer of hollow particles. Under formation temperature, the hollow volume increases and the product density decreases. The surface resin cures and the strength of the interlayer formed by the product is enhanced, resulting in a high-efficiency fracture control product that meets the requirements for buoyancy, sealing and pressure bearing performance, and whose density can be adjusted.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a high-efficiency controlled fracture product for offshore fracturing, comprising a core layer and a wrapping layer; The core layer is a hollow spherical particle, and the shell layer contains channels; The core layer is made of temperature-sensitive polymer, inorganic filler, plasticizer, anti-hydrolysis agent, antioxidant and pore-forming agent; The coating layer is made of epoxy resin and coupling agent.

[0006] Based on the above technical solution, this invention uses a temperature-sensitive polymer and other additives to prepare the core layer, and epoxy resin to prepare the coating layer, ultimately obtaining a hollow high-capacity fracturing product for marine fracturing with a porous temperature-sensitive polymer inner layer and a pre-cured resin outer layer. After entering the formation, the porous temperature-sensitive polymer in the inner layer undergoes a phase change and expands. The pre-cured resin on the surface does not hinder the expansion of the inner layer before it is fully cured. The hollow volume of the product increases, the density decreases, and the buoyancy is enhanced, which can quickly form an artificial barrier in the fracture. The density of the product can be controlled by adjusting the type and ratio of the temperature-sensitive polymer to change its phase change temperature. The pre-cured resin on the surface gradually and completely cures at the formation temperature, increasing the sealing capacity and pressure-bearing capacity of the artificial barrier.

[0007] In the aforementioned high-concentration fracturing product for offshore fracturing, further, by weight percentage, the high-concentration fracturing product for offshore fracturing is made from the following raw materials: 70-75% thermosensitive polymer, 15-20% inorganic filler, 1-2% plasticizer, 0.5-1% anti-hydrolysis agent, 0.2-0.5% antioxidant, 1-2% pore-forming agent, 2-4% epoxy resin, 0.3-0.5% coupling agent; and / or, The particle size of the high-efficiency controlled fracture product for offshore fracturing is 20-40 mesh.

[0008] Furthermore, by weight percentage, the controlled-fracture product for offshore fracturing is made from the following raw materials: 73-75% thermosensitive polymer, 17-20% inorganic filler, 1.5-2% plasticizer, 0.5-1% anti-hydrolysis agent, 0.2-0.5% antioxidant, 1-2% pore-forming agent, 2-3.6% epoxy resin, and 0.3-0.5% coupling agent.

[0009] In one embodiment of the present invention, the high-capacity fracturing product for offshore fracturing is made from the following raw materials by weight percentage: 75% thermosensitive polymer, 18% inorganic filler, 2% plasticizer, 0.5% anti-hydrolysis agent, 0.2% antioxidant, 2% pore-forming agent, 2% epoxy resin, and 0.3% coupling agent.

[0010] In one embodiment of the present invention, the high-capacity fracturing product for offshore fracturing is made from the following raw materials by weight percentage: 73% thermosensitive polymer, 19% inorganic filler, 2% plasticizer, 0.7% anti-hydrolysis agent, 0.3% antioxidant, 1.5% pore-forming agent, 3% epoxy resin, and 0.5% coupling agent.

[0011] In one embodiment of the present invention, the high-capacity fracturing product for offshore fracturing is made from the following raw materials by weight percentage: 74% thermosensitive polymer, 17% inorganic filler, 2% plasticizer, 1% anti-hydrolysis agent, 0.5% antioxidant, 1.4% pore-forming agent, 3.6% epoxy resin, and 0.5% coupling agent.

[0012] In one embodiment of the invention, the high-capacity fracturing product for offshore fracturing is made from the following raw materials by weight percentage: 74% thermosensitive polymer, 20% inorganic filler, 1.5% plasticizer, 0.5% anti-hydrolysis agent, 0.2% antioxidant, 1% pore-forming agent, 2.5% epoxy resin, and 0.3% coupling agent.

[0013] In the aforementioned high-efficiency fracturing product for offshore fracturing, the temperature-sensitive polymer is further selected from at least two of polylactic acid, polycaprolactone, polyethylene terephthalate, and polybutylene adipate terephthalate, preferably including at least polylactic acid, such as polybutylene adipate terephthalate and polylactic acid in a mass ratio of 50:25, polylactic acid and polycaprolactone in a mass ratio of 50:23, polyethylene terephthalate and polylactic acid in a mass ratio of 40:23, and polyethylene terephthalate, polylactic acid, and polycaprolactone in a mass ratio of 30:30:14; and / or, The inorganic filler is selected from at least one of activated calcium carbonate, nano-silica, and organo-bentonite; as an example, the activated calcium carbonate is Xufeng Powder's functional calcium carbonate NC-60A; as an example, the nano-silica has a diameter of 200 nm; and / or, The plasticizer is selected from at least one of citrate esters (such as tributyl citrate), polyethylene glycol, epoxidized soybean oil, and glycerin; and / or, The anti-hydrolysis agent is polycarbodiimide; and / or... The antioxidant comprises a first antioxidant and a second antioxidant, wherein the first antioxidant is a phosphite antioxidant and the second antioxidant is a hindered phenolic antioxidant; and / or, The pore-forming agent is selected from at least one of ammonium carbonate, azodicarbonamide, dinitrosopentamethylenetetramine, and sulfonyl hydrazide foaming agents (such as benzenesulfonyl hydrazide); and / or, The epoxy resin may specifically be epoxy resin E44; The coupling agent is selected from at least one of silane coupling agents and aluminate coupling agents; wherein the silane coupling agent may be one or more of KH550 (γ-aminopropyltriethoxysilane), KH560 (γ-glycidoxypropyltrimethoxysilane), KH570 (γ-methacryloyloxypropyltrimethoxysilane), and KH580 (γ-mercaptopropyltrimethoxysilane), and the aluminate coupling agent may be DL411 (isopropyl distearate aluminate).

[0014] In the aforementioned high-efficiency fracturing product for offshore fracturing, the mass ratio of the first antioxidant to the second antioxidant is further 10:(1-4), such as 10:3.3, 10:2, 10:1.1 or 10:2.5; The phosphite antioxidants include at least one of triphenyl phosphite and antioxidant 168; The hindered phenolic antioxidant includes at least one of 2,6-di-tert-butyl-4-methylphenol, antioxidant 1010, and antioxidant 1076.

[0015] In this invention, the chemical name of antioxidant 168 is tris(2,4-di-tert-butylphenyl) phosphite; the chemical name of antioxidant 1010 is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; and the chemical name of antioxidant 1076 is octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0016] Secondly, the present invention provides a method for preparing the high-efficiency controlled-fracture product for offshore fracturing as described in any of the above claims, comprising the following steps: S1. The temperature-sensitive polymer, the inorganic filler, the plasticizer, the anti-hydrolysis agent and the antioxidant are uniformly mixed and melt-blended, and then granulated to obtain temperature-sensitive polymer particles; S2. The temperature-sensitive polymer particles and the pore-forming agent are mixed and crushed, water is added and stirred to form a slurry, and then granulated to form spherical particles with hollow interiors and porous shells. S3. Mix the spherical particles, the epoxy resin and the coupling agent evenly, and then coat the spherical particles with an outer layer to obtain the high-efficiency fracturing product for offshore fracturing.

[0017] In the above-mentioned method for preparing high-efficiency controlled fracture products for marine fracturing, further, in step S1, the granulation is carried out using screw granulation.

[0018] In the above-mentioned method for preparing high-quality controlled-fracture products for marine fracturing, further, in step S2, the mixing and pulverizing step involves pulverizing the product into uniform particles of 100-200 mesh, preferably 150-200 mesh, such as 180 mesh, 170 mesh, or 200 mesh; and / or, In step S2, the mass concentration of the slurry is 40%–60%, such as 50%; and / or, In step S2, the granulation is carried out by spray drying granulation at a temperature of 180-350°C, preferably 200-300°C, such as 220°C, 200°C, 260°C or 280°C.

[0019] In the above-mentioned method for preparing high-efficiency controlled-fracture products for marine fracturing, the method further includes the following step between step S2 and step S3: activating the spherical particles at a temperature of 40–200°C and a pressure of 30–100 MPa for 10–30 min, and then cooling them to room temperature; preferably activating them at 50–150°C and a pressure of 40–80 MPa for 15–25 min, such as activating them at 50°C and a pressure of 40 MPa for 15 min, at 90°C and a pressure of 50 MPa for 16 min, at 130°C and a pressure of 60 MPa for 20 min, or at 150°C and a pressure of 70 MPa for 18 min; and / or, In step S3, the granulation is carried out by centrifugal granulation.

[0020] Thirdly, the present invention provides a method for controlling fracture height in offshore fracturing, using the offshore fracturing fracture height control product described in any one of the above descriptions or the offshore fracturing fracture height control product prepared by the method described in any one of the above descriptions.

[0021] In the above-mentioned high-temperature controlled fracture method for offshore fracturing, the target reservoir formation temperature is 50-150℃, such as 50℃, 90℃, 130℃, or 150℃, and the formation pressure is 30-60MPa, such as 30MPa, 40MPa, 55MPa, or 60MPa.

[0022] Compared with the prior art, the present invention has the following beneficial effects: This invention involves uniformly mixing and melting a temperature-sensitive polymer, inorganic filler, plasticizer, anti-hydrolysis agent, and antioxidant, followed by granulation using a screw extruder to obtain temperature-sensitive polymer particles. The temperature-sensitive polymer particles and a pore-forming agent are then mixed and pulverized into uniform particles of 100-200 mesh. Water is added and stirred to form a slurry. This slurry is then spray-dried at 180-350°C to produce spherical particles with hollow interiors and porous outer shells. The hollow particles are placed in a high-temperature, high-pressure autoclave and activated for 10-30 minutes at 40-200°C and 30-100 MPa. Afterward, the particles are rapidly cooled to room temperature. Epoxy resin and a coupling agent are then uniformly mixed, and the cooled hollow particles are coated with the outer layer using centrifugal granulation to obtain the final product.

[0023] The fracture control product of this invention is a hollow spherical particle. First, a porous shell is formed using a temperature-sensitive polymer with a phase transition temperature lower than the formation temperature. The particles are then activated and compressed under formation temperature and pressure conditions exceeding formation pressure. After compression, they are rapidly cooled and shaped, and an outer layer of pre-cured resin is applied. When this fracture control product enters the formation, the porous temperature-sensitive polymer in the inner layer undergoes a phase transition and expands. The pre-cured resin on the surface does not hinder the expansion of the inner layer before it is fully cured. This increases the hollow volume and decreases the density of the product, enhancing its buoyancy and allowing it to quickly form an artificial barrier within the fracture. The density of the product can be controlled by adjusting the type and ratio of the temperature-sensitive polymer to change its phase transition temperature. The pre-cured resin on the surface gradually and completely cures at formation temperature, increasing the sealing and pressure-bearing capacity of the artificial barrier. This highly efficient fracture control product of the invention ensures the effectiveness of fracture control and improves the success rate of offshore fracturing operations. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view of the product of the present invention during its preparation and application.

[0025] In the figure: 1- Hollow thermosensitive polymer particles obtained by spray drying are compressed and activated under high temperature and high pressure; 2- Particles after compression activation and cooling are wrapped with pre-cured resin; 3- The product of this invention; 4- The inner layer of the product expands at the ground temperature; 5- The surface pre-cured resin is completely cured. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0027] Unless otherwise specified, the methods used in the following embodiments are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following embodiments are commercially available.

[0028] The polybutylene adipate in the following examples is Kingfa Science & Technology's A400; Polylactic acid is Fengyuan Futailai FY801; The polycarbodiimide is BASF Baltanex WP20; Polycaprolactone is Kangmai PCL11000; The polyethylene glycol is polyethylene glycol 200; Polyethylene terephthalate (PET) is constant-flow bottle grade PET; The activated calcium carbonate in the following examples is Xufeng Powder's functional calcium carbonate NC-60A.

[0029] Example 1 The target reservoir has a formation temperature of 50℃ and a formation pressure of 30MPa.

[0030] according to Figure 1 The schematic diagram shown is prepared using the following specific steps: Mix 50 kg of polybutylene adipate terephthalate, 25 kg of polylactic acid, 18 kg of activated calcium carbonate, 2 kg of epoxidized soybean oil, 0.5 kg of polycarbodiimide, 0.15 kg of triphenyl phosphite, and 0.05 kg of... A mixture of 2,6-di-tert-butyl-4-methylphenol was uniformly mixed and melt-blended. Thermosensitive polymer particles were then obtained by screw granulation. These particles were mixed with 2 kg of ammonium carbonate and pulverized into uniform 180-mesh particles. Water was added and stirred to form a slurry with a concentration of 50%. The slurry was spray-dried to form particles, which were then dried at 220°C and cooled to obtain spherical particles with hollow interiors and porous shells. The hollow particles were placed in a high-temperature, high-pressure autoclave and activated for 15 minutes at 50°C and 40 MPa. After rapid cooling to room temperature, 2 kg of epoxy resin (Sinopec E44) and 0.3 kg of aluminate coupling agent (DL411) were uniformly mixed. The cooled hollow particles were then coated with a centrifugal granulator to form 20-40 mesh particles, resulting in a high-efficiency, high-quality fracturing product suitable for offshore fracturing in the target reservoir.

[0031] Example 2 The target reservoir has a formation temperature of 90℃ and a formation pressure of 40MPa.

[0032] according to Figure 1 The schematic diagram shown is prepared using the following specific steps: Mix 50 kg of polylactic acid, 23 kg of polycaprolactone, 19 kg of organobentonite, 2 kg of polyethylene glycol, 0.7 kg of polycarbodiimide, 0.25 kg of antioxidant 168, and 0.05 kg of... A mixture of 2,6-di-tert-butyl-4-methylphenol was uniformly mixed and melt-blended. Thermosensitive polymer particles were then obtained by screw granulation. These particles were mixed with 1.5 kg of azodicarbonamide and pulverized into uniform 200-mesh particles. Water was added and stirred to form a slurry with a concentration of 50%. The slurry was spray-dried to form particles, which were then dried at 200°C and cooled to obtain spherical particles with hollow interiors and porous outer shells. These hollow particles were placed in a high-temperature, high-pressure autoclave and activated for 16 minutes at 90°C and 50 MPa. After rapid cooling to room temperature, 3 kg of epoxy resin (Sinopec E44), 0.3 kg of aluminate coupling agent (DL411), and 0.2 kg of silane coupling agent (Kh550) were uniformly mixed. The cooled hollow particles were then coated with a centrifugal granulator to form 20-40 mesh particles, resulting in a high-efficiency, high-quality fracturing product suitable for offshore fracturing in the target reservoir.

[0033] Example 3 The target reservoir has a formation temperature of 130℃ and a formation pressure of 55MPa.

[0034] according to Figure 1 The schematic diagram shown is prepared using the following specific steps: A mixture of 40 kg polyethylene terephthalate, 34 kg polylactic acid, 17 kg nano-silica (200 nm particle size), 2 kg tributyl citrate, 1 kg polycarbodiimide, 0.45 kg antioxidant 168, and 0.05 kg antioxidant 1010 was uniformly mixed and melt-blended. The mixture was then granulated using a screw extruder to obtain temperature-sensitive polymer particles. These particles were then mixed with 1.4 kg dinitrosopentamethylenetetramine and pulverized into uniform 180-mesh particles. Water was added and stirred to form a slurry with a concentration of 50%. The slurry was spray-dried to form granules, which were then dried at 260°C and cooled. Afterwards, spherical particles with hollow interiors and porous shells were obtained. The hollow particles were placed in a high-temperature and high-pressure autoclave and activated for 20 minutes at 130°C and 60 MPa. Then, they were rapidly cooled to room temperature. 3.6 kg of epoxy resin (Sinopec epoxy resin E44) and 0.5 kg of silane coupling agent (0.3 kg of silane coupling agent KH560 and 0.2 kg of silane coupling agent KH570) were mixed evenly. The cooled hollow particles were then coated with centrifugal granulation to form 20-40 mesh particles, thus obtaining a high-efficiency fracture control product suitable for offshore fracturing in the target reservoir.

[0035] Example 4 The target reservoir has a formation temperature of 150℃ and a formation pressure of 60MPa.

[0036] according to Figure 1 The schematic diagram shown is prepared using the following specific steps: A mixture of 30 kg polyethylene terephthalate, 30 kg polylactic acid, 14 kg polycaprolactone, 10 kg activated calcium carbonate, 10 kg nano-silica (200 nm), 1 kg epoxidized soybean oil, 0.5 kg glycerol, 0.5 kg polycarbodiimide, 0.16 kg triphenyl phosphite, and 0.04 kg antioxidant 1076 was uniformly mixed and melt-blended. The mixture was then granulated using a screw extruder to obtain temperature-sensitive polymer particles. These particles were then mixed with 1 kg of a sulfonyl hydrazine foaming agent (benzenesulfonyl hydrazine) and pulverized into uniform 170-mesh particles. Water was added and stirred to form a slurry with a concentration of 50%. After the slurry is spray-dried to form particles, it is dried at 280℃ and cooled to obtain spherical particles with hollow interiors and porous shells. The hollow particles are placed in a high-temperature and high-pressure autoclave and activated at 150℃ and 70MPa for 18 minutes. After that, they are rapidly cooled to room temperature. 2.5kg of epoxy resin (Sinopec epoxy resin E44) and 0.3kg of silane coupling agent (silane coupling agent KH580) are mixed evenly. The cooled hollow particles are coated with a centrifugal granulator to form 20-40 mesh particles, thus obtaining a high-efficiency fracture control product suitable for offshore fracturing in the target reservoir.

[0037] Performance test examples The pressure-bearing plugging performance was tested according to the temporary plugging performance evaluation method in "SY / T 7811-2024 Soluble Solid Temporary Plugging Agents for Fracturing and Acidizing". The high-temperature and high-pressure floating performance was tested using a high-temperature and high-pressure visualization reactor. 2g of the high-pressure control product was added to the visualization reactor, and then a carrier liquid (such as guar gum base liquid) was added to the 100ml mark on the visualization window. The magnetic stirring was turned on to make the high-pressure control product evenly distributed in the carrier liquid. The temperature and pressure were adjusted to the specified values, the stirring was stopped, and the time taken for all the high-pressure control products to float was recorded. The controlled seam height experiment was conducted using a visual dynamic plate device. The controlled seam height product was prepared in a certain proportion in a carrier liquid, and the solution was placed in a storage tank and pumped into the visual plate. The time required for the controlled seam height product to float up and form a partition with an average thickness of 10 cm was observed.

[0038] The performance of the high-seam control products prepared in Examples 1-4 was evaluated according to the above methods, and the results are shown in the table below: Table 1. Performance test results of high-seam control products in Examples 1-4

[0039] As can be seen from the data in Table 1, the high-pressure fracturing products prepared in Examples 1-4 all floated completely within one minute under the target reservoir temperature and pressure conditions, and the effective sealing time was greater than two days. In the high-pressure fracturing experiment, the upper baffle of the specified thickness was formed in about 10 minutes. All of the above properties meet the requirements for the use of high-pressure fracturing products in field fracturing.

[0040] The present invention has been described in detail above. Those skilled in the art will recognize that the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope. While specific embodiments have been provided, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including modifications made using conventional techniques known in the art that depart from the scope disclosed herein.

Claims

1. A high-performance product for controlled fracturing at sea, characterized in that, Includes the core layer and the encapsulation layer; The core layer is a hollow spherical particle, and the shell layer contains channels; The core layer is made of temperature-sensitive polymer, inorganic filler, plasticizer, anti-hydrolysis agent, antioxidant and pore-forming agent; The coating layer is made of epoxy resin and coupling agent.

2. The high-performance controlled-fracture product for offshore fracturing according to claim 1, characterized in that: By weight percentage, the controlled-fracture product for offshore fracturing is made from the following raw materials: 70-75% thermosensitive polymer, 15-20% inorganic filler, 1-2% plasticizer, 0.5-1% anti-hydrolysis agent, 0.2-0.5% antioxidant, 1-2% pore-forming agent, 2-4% epoxy resin, and 0.3-0.5% coupling agent; and / or, The particle size of the high-efficiency controlled fracture product for offshore fracturing is 20-40 mesh.

3. The high-performance controlled-fracture product for offshore fracturing according to claims 1-2, characterized in that: The temperature-sensitive polymer is selected from at least two of polylactic acid, polycaprolactone, polyethylene terephthalate, and polybutylene adipate terephthalate; and / or The inorganic filler is selected from at least one of activated calcium carbonate, nano-silica, and organobentonite; and / or The plasticizer is selected from at least one of citrate, polyethylene glycol, epoxidized soybean oil, and glycerin; and / or, The anti-hydrolysis agent is polycarbodiimide; and / or... The antioxidant comprises a first antioxidant and a second antioxidant, wherein the first antioxidant is a phosphite antioxidant and the second antioxidant is a hindered phenolic antioxidant; and / or, The pore-forming agent is selected from at least one of ammonium carbonate, azodicarbonamide, dinitrospentamethylenetetramine, and sulfonyl hydrazide foaming agents; and / or, The coupling agent is selected from at least one of silane coupling agents and aluminate coupling agents.

4. The high-performance controlled-fracture product for offshore fracturing according to claim 3, characterized in that: The mass ratio of the first antioxidant to the second antioxidant is 10:(1-4); The phosphite antioxidants include at least one of triphenyl phosphite and antioxidant 168; The hindered phenolic antioxidant includes at least one of 2,6-di-tert-butyl-4-methylphenol, antioxidant 1010, and antioxidant 1076.

5. The method for preparing high-quality controlled-fracture products for marine fracturing according to any one of claims 1-4, characterized in that, Includes the following steps: S1. The temperature-sensitive polymer, the inorganic filler, the plasticizer, the anti-hydrolysis agent and the antioxidant are uniformly mixed and melt-blended, and then granulated to obtain temperature-sensitive polymer particles; S2. The temperature-sensitive polymer particles and the pore-forming agent are mixed and crushed, water is added and stirred to form a slurry, and then granulated to form spherical particles with hollow interiors and porous shells. S3. Mix the spherical particles, the epoxy resin and the coupling agent evenly, and then coat the spherical particles with an outer layer to obtain the high-efficiency fracturing product for offshore fracturing.

6. The method for preparing high-quality controlled-fracture products for offshore fracturing according to claim 5, characterized in that: In step S1, the granulation is carried out using screw granulation.

7. The method for preparing high-quality controlled-fracture products for offshore fracturing according to any one of claims 5-6, characterized in that: In step S2, the mixing and pulverizing step involves pulverizing the material into uniform particles of 100-200 mesh; and / or, In step S2, the mass concentration of the slurry is 40%–60%; and / or, In step S2, the granulation is carried out by spray drying granulation at a temperature of 180–350°C.

8. The method for preparing high-quality controlled-fracture products for offshore fracturing according to any one of claims 5-7, characterized in that: The method further includes the following step between step S2 and step S3: activating the spherical particles at a temperature of 40–200°C and a pressure of 30–100 MPa for 10–30 min, followed by cooling to room temperature; and / or, In step S3, the granulation is carried out by centrifugal granulation.

9. A method for controlling fractures in offshore fracturing, characterized in that, The high-capacity fracturing product for offshore fracturing prepared by any one of claims 1-5 or by any one of claims 6-8.

10. The method for controlling fracture height in offshore fracturing according to claim 9, characterized in that: The target reservoir has a formation temperature of 50–150℃ and a formation pressure of 30–60 MPa.

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