Intumescent pressure-resistant material, method of manufacture and intumescent pressure-resistant sealant

Abstract

The application provides a preparation method of an intumescent pressure-resistant material and the intumescent pressure-resistant material prepared therefrom, and comprises the following steps: S1, preparation of a first mixture: mixing a thermosetting resin with a first curing agent to obtain the first mixture; S2, preparation of a second mixture: mixing a second curing agent with water to obtain the second mixture; S3, preparation of a third mixture: uniformly mixing the first mixture with the second mixture, adding a promoter and a foaming agent, adjusting the rotating speed to 700 rpm-3000 rpm under the conditions of 60 DEG C-85 DEG C and 0.3-3 MPa, and stirring for greater than or equal to 10 min to obtain the third mixture; and S4, curing: allowing the third mixture to be cured under the condition of 0.3-3 MPa to obtain the intumescent pressure-resistant material. In the application, steps S3 and S4 are carried out under high pressure, and the intumescent pressure-resistant material prepared has a higher intumescent temperature, a higher high-temperature mechanical strength, and a stronger sealing ability of functional water.

Description

Technical Field

[0001] This invention relates to the field of oil well leakage prevention and plugging materials, specifically to expandable pressure-resistant materials, preparation methods, and expandable pressure-resistant plugging agents. Background Technology

[0002] Intumescent and compressive strength materials typically refer to materials that can expand in volume when exposed to water, heat, or other external stimuli, and still maintain a certain compressive strength after expansion. These materials have excellent sealing properties and compressive strength, effectively preventing the leakage of fluids or gases.

[0003] Well leakage refers to the phenomenon where working fluids (including drilling fluid, cement slurry, completion fluid, etc.) leak into the formation under pressure differential during downhole operations such as drilling, cementing, and testing. Currently, bridging plugging has proven to be a highly effective method for addressing fracture-related leakage. However, the success of this method highly depends on two key factors: a precise understanding of the formation leakage pathways and the scientific formulation of the plugging materials. Traditional intumescent pressure-resistant materials have limitations in both aspects. They lack self-adaptive properties and are difficult to adjust flexibly according to changes in formation conditions. Some intumescent pressure-resistant materials that can adapt to formation conditions have complex compositions, cumbersome preparation processes, and difficulty in guaranteeing plugging strength, especially at high temperatures.

[0004] Chinese patent CN108219332A discloses "An Oil-Absorbing and Expanding Material and Its Preparation Method and Application." This invention relates to an oil-absorbing and expanding material prepared from the following raw material components in parts by weight: 40-60 parts rubber, 20-40 parts polybutyl acrylate-methyl methacrylate copolymer, 2-5 parts vulcanizing agent, 2-5 parts vulcanization accelerator, and 10-20 parts inert filler. Using rubber as the main component, supplemented with synergistically formulated polybutyl acrylate-methyl methacrylate copolymer, vulcanizing agent, vulcanization accelerator, and inert material, the oil-absorbing and expanding performance and compressive strength of the rubber base material can be significantly improved. The polybutyl acrylate-methyl methacrylate copolymer is a low-crosslinked high-molecular-weight polymer, insoluble in oil and organic solvents, but capable of absorbing several to tens of times its own weight in oil, thus undergoing volume expansion. Even under pressure, it retains 75-80% of the oil, playing a role in expansion. Rubber is plasticized at 60–80°C for 20–40 min to obtain plasticized rubber; the plasticized rubber is mixed with polybutyl acrylate-methyl methacrylate copolymer and inert filler, and then subjected to a first mixing at 120–140°C for 30–60 min to obtain a first compound; the first compound is mixed with a vulcanizing agent and a vulcanization accelerator, and then subjected to a second mixing at 60–80°C for 20–40 min to obtain a second compound; the second compound is vulcanized at 140–160°C for 30–60 min to obtain an oil-absorbing and swelling material.

[0005] Since the oil-absorbing and expanding materials in the aforementioned patents cannot be proven to simultaneously possess expansion and pressure resistance under high-temperature conditions, there is an urgent need to develop an expansion-sealing material with stable mechanical properties at high temperatures to improve the success rate of sealing complex leaks. Summary of the Invention

[0006] The purpose of this invention is to overcome the problem that the compressive strength of thermosetting resin materials under high temperature conditions is difficult to guarantee in the prior art. It provides an intumescent compressive material, a preparation method and an intumescent compressive sealing agent. The use of this intumescent compressive material realizes the high volume expansion of thermosetting resin materials under high temperature conditions while improving the overall mechanical strength of the material.

[0007] To achieve the above objectives, a first aspect of the present invention provides a method for preparing an expansion-resistant compressive material, comprising the following steps:

[0008] Preparation of the first mixture S1: The thermosetting resin is mixed with the first curing agent to obtain the first mixture;

[0009] Preparation of the second mixture S2: Mix the second curing agent with water to obtain the second mixture;

[0010] Preparation of the third mixture S3: Mix the first mixture and the second mixture evenly, add the accelerator and foaming agent, and stir for ≥10 minutes at 60℃~85℃ and 0.3~3MPa with the speed adjusted to 700rpm~3000rpm to obtain the third mixture;

[0011] S4 curing: The third mixture is cured at 0.3 to 3 MPa to obtain the expansion and pressure-resistant material.

[0012] In step S1, the thermosetting resin undergoes a crosslinking reaction with the first curing agent to obtain a pre-crosslinked body. In step S3, the second curing agent is added to the pre-crosslinked body, mixed evenly, and then an accelerator and a foaming agent are added before curing. Adding the first and second curing agents in steps, with the thermosetting resin and the first curing agent forming the pre-crosslinked body first, allows for easier control of the crosslinking reaction rate and direction compared to adding both simultaneously. Furthermore, the resulting pre-crosslinked body and the second curing agent are more evenly distributed, resulting in a material with high high-temperature mechanical strength and strong sealing ability for functional water.

[0013] This invention further reveals that: preparing the third mixture under high pressure allows for closer contact between the first and second mixtures, facilitating further cross-linking reactions and thus improving reaction efficiency. Under pressure, the wetting effect of the thermosetting resin is enhanced, resulting in a more uniform distribution of the pre-crosslinked body obtained in step S1 and the second curing agent. This leads to higher high-temperature mechanical strength in the resulting intumescent and pressure-resistant material, and stronger sealing ability of the functional water. Pressure curing significantly improves the structural density of the intumescent and pressure-resistant material, prevents delamination and bubble formation during curing, and enhances the material's mechanical strength and sealing ability. Furthermore, the pressure curing process allows for precise control of the resin content in the intumescent and pressure-resistant material by controlling the pressure, extruding excess resin and thus making its performance and structure more stable.

[0014] In the preparation process of the intumescent and pressure-resistant material of the present invention, a steam-driven process is used to seal functional water in the first mixture prepared in step S1 and then cure it. When the temperature rises to 100°C or above, the functional water sealed in the material boils due to reaching its boiling point, and its volume expands. The higher the temperature, the greater the expansion energy, and the greater the expansion amount. This preparation method simplifies the process of thermosetting shape memory resins, which must first be hot-pressed to achieve expansion, changing the linear expansion of the resin to a high-proportion volumetric expansion, with an expansion rate as high as 660%, significantly enhancing its adaptability to filling and sealing spaces.

[0015] In some embodiments of the present invention, in step S1, the thermosetting resin is heated to 60°C to 85°C, the first curing agent is added, the temperature is adjusted to 5°C to 30°C above the melting point of the first curing agent, and after the first curing agent is completely dissolved, it is stirred at a stirring speed of 200 to 400 rpm for 20 to 60 minutes, and then adjusted to 60°C to 85°C to obtain the first mixture.

[0016] In some embodiments of the present invention, step S2 includes step S2-1, step S2-2 or step S2-3;

[0017] Step S2-1: The second curing agent is a solid with a melting point ≥90℃. Add the second curing agent to the solution and adjust the temperature to 5℃~30℃ above the melting point of the second curing agent. After the second curing agent is completely dissolved, adjust the temperature to 60℃~85℃, add water, and stir at a stirring speed of 200~400rpm for 20~60min to obtain the second mixture.

[0018] Step S2-2: The second curing agent is a solid with a melting point <90℃. Add the second curing agent to water and heat it to 5℃~10℃ above the melting point of the second curing agent. After the second curing agent is completely dissolved, adjust the temperature to 60℃~85℃ and stir at a stirring speed of 200~400rpm for 20~60min to obtain the second mixture.

[0019] Step S2-3: The second curing agent is a liquid. Adjust the temperature to 60℃~85℃, add water to the second curing agent, and stir at a stirring speed of 200~400rpm for 20~60min to obtain the second mixture.

[0020] In some embodiments of the present invention, in step S3, nitrogen gas is introduced to pressurize the mixture, the second mixture is added to the first mixture, an accelerator and a foaming agent are added, and the mixture is stirred for 10-30 minutes to obtain a third mixture.

[0021] In some embodiments of the present invention, in step S4, the pressure curing includes two or all three of the following: first curing, second curing, and third curing; the first curing is carried out at a constant temperature of 100℃~110℃ for 2h~8h; the second curing is carried out at a constant temperature of 120℃~130℃ for 0.5h~4h; and the third curing is carried out at a constant temperature of 140℃~160℃ for 0.5h~4h.

[0022] In some embodiments of the present invention, the first curing agent and the second curing agent may be the same or different, and each is independently selected from one or more of acid anhydride curing agents, phenolic curing agents, and aromatic polyamine curing agents.

[0023] In some embodiments of the present invention, the mass ratio of the first curing agent to the second curing agent is (0.60-3):1.

[0024] In some embodiments of the present invention, based on 100 parts by weight of thermosetting resin, the total amount of the first curing agent and the second curing agent is 50 to 100 parts by weight, the amount of accelerator is 0 to 2 parts by weight, the amount of water is 10 to 50 parts by weight, and the amount of foaming agent is 0.1 to 3 parts by weight.

[0025] This invention obtains an expansion-resistant and pressure-resistant material with high expansion rate and high mechanical strength under high temperature environment by further adjusting the amounts of the thermosetting resin, the first curing agent and the second curing agent, the accelerator, water and the foaming agent.

[0026] In some embodiments of the present invention, the thermosetting resin comprises one or more of epoxy resin, phenolic resin, polyetherketone resin, and polyimide resin.

[0027] In some embodiments of the present invention, the accelerator comprises one or more of triethanolamine, dimethylaniline, and 2,4,6-tris(dimethylaminomethyl)phenol.

[0028] In some embodiments of the present invention, the water is fresh water or salt water.

[0029] In some embodiments of the present invention, a foam enhancer is added to the water.

[0030] In some embodiments of the present invention, the foaming agent comprises one or more of anionic foaming agents, cationic foaming agents, and nonionic foaming agents.

[0031] In some embodiments of the present invention, the amount of the solution used is 10 to 20 parts by weight.

[0032] In some embodiments of the present invention, the solution contains at least one of a liquid resin curing agent and a liquid resin toughening agent.

[0033] In some embodiments of the present invention, the solution contains at least one of a modified aromatic amine liquid curing agent, a modified phenolic high-temperature curing agent, and an alkenyl succinic anhydride.

[0034] In some embodiments of the present invention, the epoxy resin comprises one or more of glycidyl ether epoxy resin, glycidyl amine epoxy resin, glycidyl ester epoxy resin, imide-modified epoxy resin, and phenolic-modified epoxy resin.

[0035] In some embodiments of the present invention, the epoxy resin comprises one or more of bisphenol A diglycidyl ether, phenolic epoxy resin, and imide epoxy resin.

[0036] In some embodiments of the present invention, the epoxy resin comprises one or both of bisphenol A diglycidyl ether E51 and phenolic epoxy resin F51.

[0037] In some embodiments of the present invention, the anhydride curing agent comprises one or more of maleic anhydride, alkenyl succinic anhydride (ASA), phthalic anhydride (PA), cyclopentetrate dianhydride (CPTA), and methyl hexahydrophthalic anhydride (MHHPA).

[0038] In some embodiments of the present invention, the curing agent comprises one or two of the following: modified phenolic high-temperature curing agent F-52B or F-51A, and modified aromatic amine liquid curing agent VT5327.

[0039] In some embodiments of the present invention, the foam enhancer comprises one or more of surfactant enhancers, drilling fluid surface viscosity enhancers, or surface shear strength enhancers.

[0040] In some embodiments of the present invention, the foam enhancer comprises one or both of a surfactant or a thickening and cutting agent.

[0041] In some embodiments of the present invention, the surfactant-based foam enhancer comprises one or more of polysorbate, sorbitan monooleate, oleyl alcohol polyoxyethylene ether, and dodecyl oleate.

[0042] In some embodiments of the present invention, the thickening and cutting agent-type foam reinforcing agent comprises one or more of hydroxyethyl methyl cellulose, polyacrylamide, and sodium carboxymethyl starch.

[0043] In some embodiments of the present invention, the foam enhancer content is 0.1% to 1% by weight of the water.

[0044] In some embodiments of the present invention, the anionic foaming agent is selected from one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, sodium fatty acid methyl ester ethoxylate sulfonate, fatty alcohol glyceryl ether sulfonate, or α-olefin sulfonate.

[0045] In some embodiments of the present invention, the anionic foaming agent is selected from one or more of sodium dodecylbenzenesulfonate, fatty alcohol glyceryl ether sulfonate, or α-olefin sulfonate.

[0046] In some embodiments of the present invention, the cationic foaming agent is selected from one or more of hexadecyltrimethylammonium bromide, fatty ether triethanolamine salt, and alkylbenzene sulfonic acid triethanolamine salt.

[0047] In some embodiments of the present invention, the nonionic foaming agent is selected from one or more of coconut oil diethanolamide, cocamidopropyl dimethyl tertiary amine and oleamide propyl dimethyl tertiary amine.

[0048] A second aspect of the present invention provides an expansion-resistant material, which is prepared by the above-described preparation method.

[0049] A third aspect of the present invention provides an intumescent, pressure-resistant, leak-sealing agent, the leak-sealing agent comprising the aforementioned intumescent, pressure-resistant material.

[0050] The technical solution provided by this invention has the following beneficial effects:

[0051] 1. In step S1, the thermosetting resin undergoes a crosslinking reaction with the first curing agent to obtain a pre-crosslinked body; in step S3, the second curing agent is added to the pre-crosslinked body, mixed evenly, and then an accelerator and a foaming agent are added before curing. Adding the first and second curing agents in steps, with the thermosetting resin and the first curing agent forming the pre-crosslinked body first, allows for easier control of the crosslinking reaction rate and direction compared to adding both simultaneously. Furthermore, the resulting pre-crosslinked body and the second curing agent are more evenly distributed, resulting in a material with high high-temperature mechanical strength and strong sealing ability for functional water.

[0052] 2. The preparation of the third mixture under high pressure ensures closer contact between the first and second mixtures, facilitating further cross-linking and improving reaction efficiency. Under pressure, the wetting effect of the thermosetting resin is enhanced, resulting in a more uniform distribution of the pre-crosslinked body obtained in step S1 and the second curing agent. This leads to a higher expansion temperature, higher high-temperature mechanical strength, higher porosity, and stronger sealing ability of the functional water in the prepared intumescent and pressure-resistant material. Pressure curing significantly improves the structural density of the intumescent and pressure-resistant material, prevents delamination and bubble formation during curing, and enhances the material's expansion temperature, mechanical strength, and sealing ability. The pressure curing process is faster, sealing in more functional water. The resin content in the intumescent and pressure-resistant material can be precisely controlled by adjusting the pressure, squeezing out excess resin and thus making its performance and structure more stable.

[0053] 3. The preparation method of the expansion and compression-resistant material of the present invention realizes a high proportion of volumetric expansion of thermosetting resin, thus enhancing its self-adaptive ability. Furthermore, the preparation method simplifies the process that thermosetting shape memory resin must first be hot-pressed to achieve expansion, changing the linear expansion of the resin to a high proportion of volumetric expansion, with an expansion rate as high as 663%, thereby enhancing its adaptability to filling and sealing spaces. Detailed Implementation

[0054] To make the present invention easier to understand, the present invention will be described in detail below with reference to embodiments. These embodiments are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. Unless otherwise specified, specific conditions in the embodiments are performed according to conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, the materials used in the embodiments are commercially available products or conventional products that can be synthesized by known methods.

[0055] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0056] The main reagents used in this invention are as follows:

[0057] Bisphenol A diglycidyl ether E51 was purchased from Hubei Dongcao Chemical Technology Co., Ltd., CAS No. 1675-54-3.

[0058] The phenolic epoxy resin F51 was purchased from Nantong Xingchen Synthetic Materials Co., Ltd.

[0059] Maleic anhydride was purchased from Sinopharm Group, CAS number 108-31-6.

[0060] The alkenyl succinic anhydride (ASA) was purchased from Guangzhou Haoyi New Material Technology Co., Ltd., CAS No. 26544-38-7.

[0061] Phthalic anhydride (PA) was purchased from Shandong Sanju Chemical Technology Co., Ltd., CAS No. 85-44-9.

[0062] The modified phenolic high-temperature curing agent F-52B was purchased from Bengbu Tianyu High-Temperature Resin Materials Co., Ltd.

[0063] The modified aromatic amine liquid curing agent VT5327 was purchased from Shenzhen Huite Chemical Co., Ltd.

[0064] VT5327 is a liquid modified aromatic amine curing agent, a yellow to brown viscous liquid, mainly used as a high-temperature curing agent for epoxy resins.

[0065] Sodium dodecylbenzenesulfonate (SDBS) was purchased from Shandong Yongwang Chemical Co., Ltd., CAS No. 25155-30-0.

[0066] Sodium α-olefin sulfonate (AOS) was purchased from China National Light Industry Chemical Co., Ltd., CAS No. 68439-57-6.

[0067] The testing method used in this invention:

[0068] 1. Test methods for pore size and porosity

[0069] The expansion and compressive strength materials prepared in the examples and comparative examples were made into test samples according to a mold with specifications of 60mm×60mm×30mm. The samples were subjected to liquid nitrogen brittle fracture, and the surface morphology of the samples was observed using a Hitachi S4800 field emission scanning electron microscope to obtain their pore size and porosity.

[0070] 2. Test method for weightlessness rate

[0071] The mass of the expansion and compressive strength material prepared in the test examples and comparative examples is recorded as m1. The expansion and compressive strength material is heated to 100-300℃ at a rate of 5℃ / min, maintained at the high temperature for 4-5 hours, removed and cooled to room temperature, and its mass is recorded as m2. The first weight loss rate is calculated according to the formula: First weight loss rate = 100(m1-m2) / m1. The expansion and compressive strength material is heated to 320-380℃ at a rate of 5℃ / min, maintained at the high temperature for 4-5 hours, removed and cooled to room temperature, and its mass is recorded as m3. The second weight loss rate is calculated according to the formula: Second weight loss rate = 100(m2-m3) / m2. The expansion and compressive strength material is heated to 400-500℃ at a rate of 5℃ / min, maintained at the high temperature for 3-4 hours, removed and cooled to room temperature, and its mass is recorded as m4. The third weight loss rate is calculated according to the formula: Third weight loss rate = 100(m4-m3) / m3.

[0072] Example 1

[0073] 1-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0074] Preparation of the first mixture S1: Heat 100g of bisphenol A diglycidyl ether E51 to 60℃ and maintain the temperature for 10min. After the bisphenol A diglycidyl ether E51 becomes thin, add 20g of maleic anhydride while stirring at 300rpm. Adjust the temperature to 85℃. After the maleic anhydride dissolves, add 12g of alkenyl succinic anhydride. Continue stirring for 40min and adjust the temperature to 60℃ to obtain the first mixture.

[0075] Preparation of the second mixture S2: Add 33g of maleic anhydride to 30mL of water, adjust the temperature to 85℃, and keep stirring at 200rpm until the maleic anhydride is completely dissolved. Then add 20g of alkenyl succinic anhydride and adjust the temperature to 60℃ to obtain the second mixture.

[0076] Preparation of the third mixture S3: Add the second mixture to the first mixture, mix evenly, then add 1.1g of dimethylaniline and 0.25g of sodium dodecylbenzenesulfonate. Stir for 10 minutes at 60℃ and normal pressure (0.1MPa) with a speed of 1000rpm to obtain the third mixture.

[0077] S4 Curing: Brush silicone oil onto the mold surface, put the third mixture into the mold, place the mold in a preheated constant temperature box, keep it at 120℃ for 2 hours under normal pressure (0.1MPa), and then raise the temperature to 150℃ for 1 hour to complete the curing; after the cured body cools down, the cured body board is obtained, and after demolding, it is crushed into different particle sizes to obtain the expansion and compressive strength material.

[0078] The intumescent compressive strength material prepared in Example 1-1 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 230–280 μm, and the porosity of the intumescent compressive strength material is 14.78%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.50%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 25.9%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 56.3%.

[0079] 1-2 Preparation of Expansion-Resistant Materials under Pressure Conditions

[0080] The expansion-resistant material was prepared according to the method described in Example 1-1, except that in Example 1-2, nitrogen gas was introduced in step S3 and the pressure was maintained at 0.3 MPa; in step S4, pressure curing was performed and the pressure was maintained at 0.3 MPa.

[0081] The intumescent compressive strength materials prepared in Examples 1-2 comprise a porous structure formed by the curing of a thermosetting resin and water sealed within the porous structure. The pore size of the porous structure is 220–230 μm, and the porosity of the intumescent compressive strength material is 16.84%. DSC measurements show that at 200–270°C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.4%; at 360–370°C, the weight loss rate at the second weight loss peak is 28.2%; and above 400°C, the weight loss rate at the third weight loss peak is 58.2%.

[0082] 1-3 Preparation of Expansion-Resistant Materials under Pressure

[0083] The expansion-resistant material was prepared according to the method described in Example 1-1, except that in Example 1-3, nitrogen gas was introduced in step S3 and the pressure was maintained at 1.0 MPa; in step S4, pressure curing was performed and the pressure was maintained at 1.0 MPa.

[0084] The intumescent compressive strength materials prepared in Examples 1-3 comprise a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 210–220 μm, and the porosity of the intumescent compressive strength material is 18.96%; using DSC measurement, at 200–270°C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.2%; at 360–370°C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 30.8%; above 400°C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 60.5%.

[0085] Example 2

[0086] 2-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0087] Preparation of the first mixture S1: Heat 60g of bisphenol A diglycidyl ether E51 to 60℃ and add 40g of phenolic epoxy resin F51. After maintaining the temperature for 10min, when the bisphenol A diglycidyl ether E51 and phenolic epoxy resin F51 become thin, add 20g of alkenyl succinic anhydride and 12g of modified phenolic high-temperature curing agent F-52B while stirring at 300rpm. Adjust the temperature to 85℃ and continue stirring for 40min. Adjust the temperature to 60℃ to obtain the first mixture.

[0088] Preparation of the second mixture S2: Mix 28g of alkenyl succinic anhydride and 16g of modified phenolic high-temperature curing agent F-52B evenly, adjust the temperature to 85℃, maintain a stirring speed of 200rpm, add 30mL of water while stirring, and adjust the temperature to 60℃ to obtain the second mixture.

[0089] Preparation of the third mixture S3: Add the second mixture to the first mixture, mix well, then add 1.2g of 2,4,6-tris(dimethylaminomethyl)phenol and 0.25g of sodium α-olefin sulfonate. Stir for 10 minutes at 60℃ and normal pressure (0.1MPa) with a speed of 2000rpm to obtain the third mixture.

[0090] S4 Curing: Brush silicone oil on the mold surface, put the third mixture into the mold, put the mold into a preheated constant temperature box, keep it at 120℃ for 3 hours under normal pressure (0.1MPa), and then raise the temperature to 150℃ for 1 hour to complete the curing; after the cured body cools down, the cured body board is obtained, and after demolding, it is crushed into different particle sizes to obtain the expansion and compressive strength material.

[0091] The intumescent compressive strength material prepared in Example 2-1 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 230–280 μm, and the porosity of the intumescent compressive strength material is 10.95%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.8%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 15.8%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 51.8%.

[0092] 2-2 Preparation of Expansion-Resistant Materials under Pressure

[0093] The expansion-resistant material was prepared according to the method described in Example 2-1, except that in step S3 of Example 2-2, nitrogen gas was introduced and the pressure was maintained at 1.0 MPa; in step S4, pressure curing was performed and the pressure was maintained at 1.0 MPa.

[0094] The intumescent compressive strength material prepared in Example 2-2 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 220–230 μm, and the porosity of the intumescent compressive strength material is 12.82%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.5%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 18.2%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 53.4%.

[0095] 2-3 Preparation of Expansion-Resistant Materials under Pressure Conditions

[0096] The expansion-resistant material was prepared according to the method described in Example 2-1, except that in step S3 of Example 2-3, nitrogen gas was introduced and the pressure was maintained at 2.0 MPa; in step S4, pressure curing was performed and the pressure was maintained at 2.0 MPa.

[0097] The intumescent compressive strength materials prepared in Examples 2-3 comprise a porous structure formed by the curing of a thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 210–220 μm, and the porosity of the intumescent compressive strength material is 14.61%; using DSC measurement, at 200–270°C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.3%; at 360–370°C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 20.6%; above 400°C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 55.3%.

[0098] Example 3

[0099] 3-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0100] Preparation of the first mixture S1: Heat 100g of bisphenol A diglycidyl ether E51 to 85℃ and maintain the temperature for 10min. After the bisphenol A diglycidyl ether E51 becomes thin, add 20g of phthalic anhydride PA while stirring at 300rpm. Adjust the temperature to 135℃ and add 12g of modified aromatic amine liquid curing agent VT5327. After the phthalic anhydride PA is completely dissolved, continue stirring for 20min and adjust the temperature to 85℃ to obtain the first mixture.

[0101] Preparation of the second mixture S2: Add 35g of phthalic anhydride PA to 18g of modified aromatic amine liquid curing agent VT5327, adjust the temperature to 135℃, maintain a stirring speed of 200rpm until the phthalic anhydride PA is completely dissolved, adjust the temperature to 85℃, and then add 40mL of water while stirring to obtain the second mixture.

[0102] Preparation of the third mixture S3: Add the second mixture to the first mixture, mix well, then add 1.2g of 2,4,6-tris(dimethylaminomethyl)phenol and 0.50g of sodium α-olefin sulfonate. Stir for 10 minutes at 85℃ and normal pressure (0.1MPa) with a speed of 2000rpm to obtain the third mixture.

[0103] S4 Curing: Brush silicone oil onto the mold surface, put the third mixture into the mold, place the mold in a preheated constant temperature box, keep it at 120℃ for 2 hours under normal pressure (0.1MPa), and then raise the temperature to 150℃ for 1 hour to complete the curing; after the cured body cools down, the cured body board is obtained, and after demolding, it is crushed into different particle sizes to obtain the expansion and compressive strength material.

[0104] The intumescent compressive strength material prepared in Example 3-1 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 230–280 μm, and the porosity of the intumescent compressive strength material is 14.57%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.3%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 24.5%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 45.3%.

[0105] 3-2 Preparation of Expansion-Resistant Materials under Pressure

[0106] The expansion-resistant material was prepared according to the method described in Example 3-1, except that in step S3 of Example 3-2, nitrogen gas was introduced and the pressure was maintained at 0.5 MPa; in step S4, pressure curing was performed and the pressure was maintained at 0.5 MPa.

[0107] The intumescent compressive strength material prepared in Example 3-2 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 220–230 μm, and the porosity of the intumescent compressive strength material is 16.54%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.0%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 26.8%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 47.2%.

[0108] 3-3 Preparation of Expansion-Resistant Materials under Pressure

[0109] The expansion-resistant material was prepared according to the method described in Example 3-1, except that in step S3 of Example 3-3, nitrogen gas was introduced and the pressure was maintained at 1.3 MPa; in step S4, pressure curing was performed and the pressure was maintained at 1.3 MPa.

[0110] The intumescent compressive strength material prepared in Examples 3-3 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 210–220 μm, and the porosity of the intumescent compressive strength material is 18.52%; using DSC measurement, at 200–270°C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 0.9%; at 360–370°C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 28.9%; above 400°C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 50.6%.

[0111] Comparative Example 1

[0112] 1-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0113] The expansion and compression-resistant material was prepared according to the method described in Example 3-1, except that all curing agents were added at once, and the required phthalic anhydride PA and modified aromatic amine liquid curing agent VT5327 were all added to bisphenol A diglycidyl ether E51 at once.

[0114] The intumescent compressive-resistant material prepared in Comparative Example 1-1 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 300–320 μm, and the porosity of the intumescent compressive-resistant material is 16.98%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive-resistant material at the first weight loss peak is 1.8%; at 360–370 °C, the weight loss rate of the intumescent compressive-resistant material at the second weight loss peak is 28.5%; above 400 °C, the weight loss rate of the intumescent compressive-resistant material at the third weight loss peak is 41.3%.

[0115] 1-2 Preparation of Expansion-Resistant Materials under Pressure Conditions

[0116] The expansion and compression-resistant material was prepared according to the method described in Example 3-2, except that all curing agents were added at once, and the required phthalic anhydride PA and modified aromatic amine liquid curing agent VT5327 were all added to bisphenol A diglycidyl ether E51 at once.

[0117] The intumescent compressive strength materials prepared in Comparative Examples 1-2 comprise a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 270–300 μm, and the porosity of the intumescent compressive strength material is 18.05%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.5%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 30.8%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 43.6%.

[0118] 1-3 Preparation of Expansion-Resistant Materials under Pressure

[0119] The expansion and compression-resistant material was prepared according to the method described in Examples 3-3, except that all curing agents were added at once, and the required phthalic anhydride PA and modified aromatic amine liquid curing agent VT5327 were all added to bisphenol A diglycidyl ether E51 at once.

[0120] The intumescent compressive strength materials prepared in Comparative Examples 1-3 comprise a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 250–270 μm, and the porosity of the intumescent compressive strength material is 19.28%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.2%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 33.6%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 46.5%.

[0121] Comparative Example 2

[0122] 2-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0123] The expansion-resistant material was prepared according to the method described in Example 3-1, except that 1.2 g of 2,4,6-tris(dimethylaminomethyl)phenol was not added in step S3. In step S4, the material was kept at a constant temperature of 100°C for 10 h, then heated to 120°C and kept at that temperature for 6 h, and then heated to 150°C and kept at that temperature for 4 h.

[0124] The intumescent compressive-resistant material prepared in Comparative Example 2-1 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 320–350 μm, and the porosity of the intumescent compressive-resistant material is 12.35%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive-resistant material at the first weight loss peak is 3.0%; at 360–370 °C, the weight loss rate of the intumescent compressive-resistant material at the second weight loss peak is 24.1%; above 400 °C, the weight loss rate of the intumescent compressive-resistant material at the third weight loss peak is 56.8%.

[0125] 2-2 Preparation of Expansion-Resistant Materials under Pressure

[0126] The expansion-resistant material was prepared according to the method described in Examples 3-2, except that in step S3, 1.2 g of 2,4,6-tris(dimethylaminomethyl)phenol was not added. In step S4, the material was kept at a constant temperature of 100°C for 10 h, then heated to 120°C and kept at that temperature for 6 h, and then heated to 150°C and kept at that temperature for 4 h.

[0127] The intumescent compressive strength material prepared in Comparative Example 2-2 comprises a porous structure formed by the curing of a thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 300–320 μm, and the porosity of the intumescent compressive strength material is 15.28%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 2.7%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 25.4%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 57.1%.

[0128] 2-3 Preparation of Expansion-Resistant Materials under Pressure Conditions

[0129] The expansion-resistant material was prepared according to the method described in Examples 3-3, except that in step S3, 1.2 g of 2,4,6-tris(dimethylaminomethyl)phenol was not added. In step S4, the material was kept at a constant temperature of 100°C for 10 h, then heated to 120°C and kept at that temperature for 6 h, and then heated to 150°C and kept at that temperature for 4 h.

[0130] The intumescent compressive strength materials prepared in Comparative Examples 2-3 comprise a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 270–300 μm, and the porosity of the intumescent compressive strength material is 17.61%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 2.5%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 26.8%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 58.4%.

[0131] Comparative Example 3

[0132] 3-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0133] The expansion-resistant material was prepared according to the method described in Example 3-1, except that 40 mL of water was not added in step S2.

[0134] The intumescent compressive strength material prepared in Comparative Example 3-1 comprises a porous structure formed by the curing of a thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 50–75 μm, and the porosity of the intumescent compressive strength material is 5.02%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 0%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 0%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 37.2%.

[0135] 3-2 Preparation of Expansion-Resistant Materials under Pressure

[0136] The expansion-resistant material was prepared according to the method described in Example 3-2, except that 40 mL of water was not added in step S2.

[0137] The intumescent compressive strength material prepared in Comparative Example 3-2 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 35–50 μm, and the porosity of the intumescent compressive strength material is 4.83%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 0%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 0%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 38.4%.

[0138] 3-3 Preparation of Expansion-Resistant Materials under Pressure

[0139] The expansion-resistant material was prepared according to the method described in Examples 3-3, except that 40 mL of water was not added in step S2.

[0140] The intumescent compressive strength material prepared in Comparative Example 3-3 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 25–35 μm, and the porosity of the intumescent compressive strength material is 4.35%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 0%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 0%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 39.2%.

[0141] Comparative Example 4

[0142] 4-1 Preparation of Expansion-Resistant Materials under Normal Pressure

[0143] The expansion-resistant material was prepared according to the method described in Example 3-1, except that 0.50 g of sodium α-olefin sulfonate was not added in step S3.

[0144] The intumescent compressive strength material prepared in Comparative Example 4-1 comprises a porous structure formed by the curing of a thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 120–150 μm, and the porosity of the intumescent compressive strength material is 6.21%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.5%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 4.1%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 31.8%.

[0145] 4-2 Preparation of Expansion-Resistant Materials under Pressure

[0146] The expansion-resistant material was prepared according to the method described in Examples 3-2, except that 0.50g of sodium α-olefin sulfonate was not added in step S3.

[0147] The intumescent compressive strength material prepared in Comparative Example 4-2 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 100–120 μm, and the porosity of the intumescent compressive strength material is 7.32%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.3%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 6.6%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 33.4%.

[0148] 4-3 Preparation of Expansion-Resistant Materials under Pressure

[0149] The expansion-resistant material was prepared according to the method described in Examples 3-3, except that 0.50g of sodium α-olefin sulfonate was not added in step S3.

[0150] The intumescent compressive strength material prepared in Comparative Example 4-3 comprises a porous structure formed by the curing of thermosetting resin and water sealed within the porous structure; the pore size of the porous structure is 90–100 μm, and the porosity of the intumescent compressive strength material is 8.96%; using DSC measurement, at 200–270 °C, the weight loss rate of the intumescent compressive strength material at the first weight loss peak is 1.1%; at 360–370 °C, the weight loss rate of the intumescent compressive strength material at the second weight loss peak is 9.8%; above 400 °C, the weight loss rate of the intumescent compressive strength material at the third weight loss peak is 35.3%.

[0151] Test example:

[0152] The testing method of this invention is as follows:

[0153] 1. Expansion temperature test

[0154] Test samples prepared according to a 60mm×60mm×30mm mold were immersed in a heated oil bath. The temperature was initially set to 100℃ and maintained for 5 hours after stabilization to prevent expansion. The temperature was then increased by 10℃ every 5 hours until expansion occurred. After expansion, test samples prepared under the same conditions were taken and tested in the heated oil bath for 10℃ before and after expansion. The temperature was increased by 3℃ every 5 hours until expansion was achieved. This process was repeated until the accurate expansion temperature was determined.

[0155] 2. Compressive strength test method

[0156] The expansion and compressive strength materials prepared in the examples and comparative examples were made into test samples according to a mold with a specification of 60mm×60mm×30mm. The high temperature universal testing machine was used to test the compressive strength of the samples at a test speed of 5mm / min and an arbitration test speed of 2mm / min, respectively, at room temperature and at an expansion temperature above 30℃ (Note: Before the high temperature test, silicone oil was applied to the inner cavity of the test to prevent the high temperature expansion and compressive strength material from sticking to the instrument).

[0157] 3. Tensile strength test method

[0158] The expansion and compressive strength materials obtained in the examples and comparative examples were made into test samples according to a dumbbell mold with a length of 30cm. The samples were tested using a high-temperature universal testing machine at a test speed of 5mm / min and an arbitration test speed of 2mm / min, respectively, at room temperature and at an expansion temperature above 30℃.

[0159] Using the test method of the present invention described above, the expansion temperature, compressive strength and tensile strength of Examples 1 to 3 and Comparative Examples 1 to 4 were tested, and the test results are shown in Table 1 below.

[0160] Table 1. Expansion temperature and mechanical property tests of Examples 1-3 and Comparative Examples 1-4

[0161]

[0162] As shown in Table 1, the mechanical strength (including compressive and tensile strength) loss of Examples 1-3 at an expansion temperature of +30°C is relatively small. In particular, the compressive strength retention rate after pressurization is all above 25%, and the tensile strength retention rate is all above 20%. Furthermore, the mechanical strength retention rates of Examples 1-3, 2-3, and 3-3 under high pressure in steps S3 and S4 are higher than those of other examples in the same group. In Comparative Example 1, because the curing agent of the expansion and compression-resistant material is added all at once instead of in steps as in Examples 1-3, the mechanical properties at room temperature decrease slightly, and the retention rates of both compressive and tensile strength at expansion temperatures above 30°C are reduced, with a decrease in mechanical strength after high temperature. In Comparative Example 2, because no accelerator is added, the curing time of the expansion and compression-resistant material is significantly prolonged, reaching up to 20 hours, and the mechanical strength decreases after high temperature. Comparative Example 3: Because no water was added to the expandable compressive material and no steam-driven process was used, its mechanical properties at room temperature were unaffected. However, the retention rates of compressive and tensile strengths were extremely low above the expansion temperature of 30°C, and the mechanical strength decreased significantly after reaching high temperatures. Comparative Example 4: Because no foaming agent was added to the expandable compressive material, the steam-driven process could not be fully implemented. Its mechanical properties at room temperature were unaffected, but the retention rates of compressive and tensile strengths were low above the expansion temperature of 30°C, and the mechanical strength decreased significantly after reaching high temperatures.

[0163] 4. Test methods for expansion rate and delayed expansion time

[0164] The expansion and compression-resistant materials prepared by the examples and comparative examples with a size of 60mm×60mm×30mm (the original volume was tested by the drainage method and denoted as V0) were placed in a dry tin foil tray and placed in a constant temperature forced-air drying oven. The initial expansion time and the time required to complete the expansion were tested at different preset temperatures. The initial expansion time was denoted as the delayed expansion time t0 of the material.

[0165] Continue testing and record the time t1 for the solidified body to fully expand. Then the expansion time t2 = t1 - t0.

[0166] After complete expansion, turn off the power to the drying oven and allow the expanded body to cool. Use the water displacement method to measure its expanded volume V1 and calculate the expansion rate.

[0167]

[0168] Using the test method of the present invention described above, the expansion rate, delayed expansion time and completion expansion time of Example 3 and Comparative Examples 1 to 4 at different temperatures were tested, and the test results are shown in Table 2.

[0169]

[0170]

[0171] As shown in Table 2, in Examples 3-1, 3-2, and 3-3, gradually increasing the mixing and curing pressure resulted in a slight decrease in the expansion rate, an increase in the delayed expansion time, and a shorter completion time for expansion. In Comparative Example 1, because the curing agent for the expanding and pressure-resistant material was added all at once instead of in stages as in Example 3, the expansion rate was slightly lower, and the delayed expansion time was longer, especially the high-temperature delayed expansion time. In Comparative Example 3, because water was not added to the expanding and pressure-resistant material and a steam-driven process was not used, the expanding and pressure-resistant material did not expand. In Comparative Example 4, because a foaming agent was not added to the expanding and pressure-resistant material, the steam-driven process could not be fully realized, resulting in a low expansion rate, a long delayed expansion time, and a significantly increased completion time for expansion.

[0172] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing an expansion-resistant compressive material, characterized in that, Includes the following steps: Preparation of the first mixture S1: The thermosetting resin is mixed with the first curing agent to obtain the first mixture; Preparation of the second mixture S2: Mix the second curing agent with water to obtain the second mixture; Preparation of the third mixture S3: Mix the first mixture and the second mixture evenly, add the accelerator and foaming agent, and stir for ≥10 minutes at 60℃~85℃ and 0.3~3MPa with the speed adjusted to 700rpm~3000rpm to obtain the third mixture; S4 curing: The third mixture is cured at 0.3 to 3 MPa to obtain the expansion and pressure-resistant material.

2. The method for preparing the expansion-resistant compressive material according to claim 1, characterized in that, In step S1, the thermosetting resin is heated to 60°C to 85°C, the first curing agent is added, the temperature is adjusted to 5°C to 30°C above the melting point of the first curing agent, and after the first curing agent is completely dissolved, it is stirred at a stirring speed of 200 to 400 rpm for 20 to 60 minutes, and then adjusted to 60°C to 85°C to obtain the first mixture. And / or, step S2 includes step S2-1, step S2-2, or step S2-3; Step S2-1: The second curing agent is a solid with a melting point ≥90℃. Add the second curing agent to the solution and adjust the temperature to 5℃~30℃ above the melting point of the second curing agent. After the second curing agent is completely dissolved, adjust the temperature to 60℃~85℃, add water, and stir at a stirring speed of 200~400rpm for 20~60min to obtain the second mixture. Step S2-2: The second curing agent is a solid with a melting point <90℃. Add the second curing agent to water and heat it to 5℃~10℃ above the melting point of the second curing agent. After the second curing agent is completely dissolved, adjust the temperature to 60℃~85℃ and stir at a stirring speed of 200~400rpm for 20~60min to obtain the second mixture. Step S2-3: The second curing agent is a liquid. Adjust the temperature to 60℃~85℃, add water to the second curing agent, and stir at a stirring speed of 200~400rpm for 20~60min to obtain the second mixture. And / or, in step S3, nitrogen gas is introduced to pressurize the mixture, the second mixture is added to the first mixture, an accelerator and a foaming agent are added, and the mixture is stirred for 10-30 minutes to obtain a third mixture; And / or, in step S4, the pressure curing includes two or three of the following: first curing, second curing, and third curing; the first curing is carried out at a constant temperature of 100℃~110℃ for 2h~8h; the second curing is carried out at a constant temperature of 120℃~130℃ for 0.5h~4h; and the third curing is carried out at a constant temperature of 140℃~160℃ for 0.5h~4h. And / or, the first curing agent and the second curing agent may be the same or different, and each is independently selected from one or more of acid anhydride curing agents, phenolic curing agents, and aromatic polyamine curing agents; And / or, the mass ratio of the first curing agent to the second curing agent is (0.60~3):

1.

3. The method for preparing the expansion-resistant compressive material according to claim 1 or 2, characterized in that, Based on 100 parts by weight of thermosetting resin, the total amount of the first curing agent and the second curing agent is 50 to 100 parts by weight, the amount of accelerator is 0 to 2 parts by weight, the amount of water is 10 to 50 parts by weight, and the amount of foaming agent is 0.1 to 3 parts by weight.

4. The method for preparing the expansion-resistant material according to claim 3, characterized in that, The thermosetting resin includes one or more of epoxy resin, phenolic resin, polyetherketone resin, and polyimide resin; And / or, the accelerator comprises one or more of triethanolamine, dimethylaniline, and 2,4,6-tris(dimethylaminomethyl)phenol; And / or, the water is fresh water or salt water, preferably, the water contains a foam enhancer; And / or, the foaming agent comprises one or more of anionic foaming agents, cationic foaming agents, and nonionic foaming agents.

5. The method for preparing the expansion-resistant compressive material according to any one of claims 2-4, characterized in that, The amount of the solvent is 10 to 20 parts by weight; and / or, the solvent contains at least one of a liquid resin curing agent and a liquid resin toughening agent; preferably, the solvent contains at least one of a modified aromatic amine liquid curing agent, a modified phenolic high-temperature curing agent, and an alkenyl succinic anhydride.

6. The method for preparing the expansion-resistant compressive material according to claim 3, characterized in that, The epoxy resin comprises one or more of the following: glycidyl ether epoxy resin, glycidyl amine epoxy resin, glycidyl ester epoxy resin, imide modified epoxy resin, and phenolic modified epoxy resin. And / or, the anhydride curing agent comprises one or more of maleic anhydride, alkenyl succinic anhydride, phthalic anhydride, cyclopentadienoic dianhydride, and methyl hexahydrophthalic anhydride; And / or, the foam enhancer comprises one or more of surfactant enhancers, drilling fluid surface viscosity enhancers, or surface shear strength enhancers; preferably, the foam enhancer comprises one or two of surfactants or thickening and shearing agents; more preferably, the mass content of the foam enhancer is 0.1% to 1% based on the weight of the water; And / or, the anionic foaming agent is selected from one or more of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, sodium fatty acid methyl ester ethoxylate sulfonate, fatty alcohol glyceryl ether sulfonate, or α-olefin sulfonate. And / or, the cationic foaming agent is selected from one or more of hexadecyltrimethylammonium bromide, fatty ether triethanolamine salt, and alkylbenzene sulfonic acid triethanolamine salt; And / or, the nonionic foaming agent is selected from one or more of coconut oil diethanolamide, cocamidopropyl dimethyl tertiary amine and oleamide propyl dimethyl tertiary amine.

7. The method for preparing the expansion-resistant compressive material according to claim 6, characterized in that, The epoxy resin comprises one or more of bisphenol A diglycidyl ether, phenolic epoxy resin, and imide epoxy resin. And / or, the anionic foaming agent is selected from one or more of sodium dodecylbenzene sulfonate, fatty alcohol glyceryl ether sulfonate, or α-olefin sulfonate.

8. The method for preparing the expansion-resistant compressive material according to claim 6, characterized in that, The surfactant-based foam enhancer comprises one or more of polysorbate, sorbitan monooleate, oleyl alcohol polyoxyethylene ether, and dodecyl oleate. And / or, the thickening and cutting agent-type foam enhancer comprises one or more of hydroxyethyl methyl cellulose, polyacrylamide, and sodium carboxymethyl starch.

9. An expansion-resistant material, prepared by the method described in any one of claims 1-8.

10. An intumescent, pressure-resistant, leak-sealing agent, characterized in that, The sealing agent comprises the expansion and pressure-resistant material as described in claim 9.

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