High-temperature-resistant slow-release foaming material as well as preparation method and application thereof

Abstract

The invention discloses a high-temperature-resistant slow-release foaming material as well as a preparation method and application thereof. The high-temperature-resistant slow-release foaming material comprises inorganic silica gel and a surfactant. The foaming material provided by the invention has the advantages of good molding and good temperature resistance, and can realize stable release of foaming agent activity for a long time, and after release and dispersion of a nano agglomerated material, silicon nanoparticles can be brought out of a wellhead along with airflow. The method can be used for high-temperature oil-gas wells and reduces frequent well opening and chemical agent injection.

Description

Technical Field

[0001] The present invention relates to the technical field of solid composite materials, and particularly to a high-temperature resistant and slow-release foaming material, a preparation method thereof and an application thereof. Background Art

[0002] In natural gas exploitation, as the exploitation time increases, the downhole pressure decreases, and groundwater accumulates in the wellbore, resulting in a reduction in natural gas production or even production suspension. Adding a foaming agent can produce low-density foam to discharge the wellbore base fluid. These wellbore chemical foaming agents are usually in solid or liquid form. Solid foaming rods are usually made into instant solid rods and regularly put into the wellbore by frequently opening the well. The one-time addition amount of solid foaming agent products is too large, and the effective action time is short. The slow-release technology can reduce the operation times, and the slow-release system can also effectively improve the utilization rate of active component chemicals and reduce their losses and volatilization caused by environmental factors. Liquid foaming agents are injected into the wellbore by pumps, which requires investment in installing injection pipelines and pumps. Therefore, the slow release of solid chemicals is an effective method to reduce the opening of the well and the investment in liquid injection equipment.

[0003] The slow-release technology has been applied in the fields of agriculture, medicine, oilfield chemicals, etc. In the medical field, coating drugs in slow-release capsules can reduce the number of drug administrations and extend the effective action time of drugs by several times. In terms of pesticide slow-release agents, there are many varieties, among which there are microcapsules, and the capsule shell can be natural, semi-synthetic or fully synthetic high-molecular compounds, including protein-based, high-molecular carbohydrates, cellulose-based, fatty acids and derivatives, inorganic polymers, vinyl polymers, polyamides, polyurethanes and polyesters, etc. In terms of slow-release fertilizers, modified polyvinyl alcohol is mixed with inorganic materials such as diatomite, zeolite powder, biomass charcoal, phosphate rock powder, and sulfur as coating materials for controlled-release fertilizers to reduce nitrogen loss and improve the utilization rate of nitrogen fertilizers.

[0004] Slow-release technology has been widely applied in oil fields. For example, US20160009980A1 discloses a method of mixing a porous metal oxide such as alumina, zirconia, or titania as a solid carrier and binder, and forming shaped compressed particles by a complex of a well-treated agent adsorbed on the calcined porous metal oxide or entering the gaps of the calcined porous metal oxide, which can be introduced into oil production wells or gas production wells to slowly release the active components adsorbed in the porous material. US20180134939A1 discloses cross-linking scale inhibitors and slow-release agent active substances on a carrier through chemical bonds, using the reactions of alcohols, amines, and acids for cross-linking, and slowly releasing the active substances by the hydrolysis of the cross-linking bonds underground. US20170058184A1 discloses a water-insoluble carrier composed of corn grits, which is used to adsorb liquid chemical reagents such as scale inhibitors and surfactants during the stimulation or production process in oil and gas fields. The compressive strength and liquid insolubility of the corn grits are utilized to slowly release the active chemical substances into oil and gas wells to achieve the purpose of slow release. US20120273197A1 discloses a composite material for well treatment operations such as hydraulic fracturing and sand control, which allows one or more well treatment agents to be slowly released into the underground formation and / or the wellbore penetrating the formation. It has a nanoscale calcined porous matrix (adsorbent) with a high specific surface area, and the well treatment agent is coated thereon. CN110157401A discloses a preparation method of a controllable long-acting slow-release scale inhibitor capsule. The scale inhibitor and an inorganic nano-carrier, one of the slow-release components, are assembled into a homogeneous whole in the form of a solid solution, and are coated with a cross-linked polymer composed of carboxymethyl cellulose, polyvinyl alcohol, and porous zeolite, etc., which can be controllably dissolved. When the polymer dissolves in the environmental medium, the active substance is gradually released. By using the dual controlled-release mechanism of polymer dissolution and desorption of the scale inhibitor from the inorganic nano-carrier, it can be slowly released in the wellbore to extend the protection effect on the wellbore. CN107304078A discloses an environmentally friendly slow-release polymer scale inhibitor, using a mixture of polyvinyl alcohol, sodium alginate, and gelatin solution as a carrier material, and boric acid as an additive to construct a slow-release wall material system for loading the scale inhibitor, and carrying out slow release in a simulated oil field water medium at 50°C.

[0005] Although slow-release technology has been gradually used in the exploitation of oil and gas fields, due to the complexity of the environmental characteristics of high-temperature wells, the requirements for slow-release materials are extremely strict. CN110564388A discloses a preparation method of a temperature-sensitive plugging colloid for oil and gas fields, which performs multi-phase physical adsorption and chemical pre-crosslinking on modified polyacrylamide, a trivalent crosslinking agent, a water-soluble slow-release agent, and an aqueous phase, so that the temperature-sensitive plugging colloid has the characteristics of delayed slow release of temperature-sensitive swelling, but the applicable temperature is only 60-90°C. In CN110003875A, research on slow-release foaming agents was carried out, and a surfactant foaming agent was mixed with 5-20% sausage casings to make the action time reach 120 hours (5 days), but the operating temperature of this technology is lower than 90°C, and there are disadvantages such as the storage period of animal materials being less than 3 months and inconsistent batch quality. In these studies, the selection of slow-release materials for specific conditions (such as acid resistance and temperature resistance) remains a research difficulty.

[0006] In summary, most of the slow-release materials in the prior art use materials that can be slowly dissolved to wrap surfactants to achieve slow-release effects; however, the materials used dissolve and decompose quickly at high temperatures, the surfactants will be quickly released, and the slow-release time is short.

[0007] Therefore, there is a need for a new material to solve the problems of short slow-release time and low temperature resistance of slow-release materials for oil fields existing in the prior art. Summary of the Invention

[0008] To solve the problems existing in the prior art, the present invention provides a high-temperature resistant slow-release foaming material, its preparation method and application. The high-temperature resistant slow-release foaming material of the present invention has a mesoporous nanostructure, and its main components include a foaming agent (surfactant) and inorganic silica gel; the foaming material of the present invention has the advantages of good molding and good temperature resistance, and can stably release the activity of the foaming agent for a long time. After release, after the nano-aggregated material is dispersed, the silicon nanoparticles can be carried out of the wellhead by the gas flow. It can be used in high-temperature oil and gas wells to reduce the frequent opening of wells to inject chemical agents.

[0009] One of the objectives of the present invention is to provide a high-temperature resistant slow-release foaming material, which includes inorganic silica gel and a surfactant.

[0010] In a preferred embodiment of the present invention,

[0011] The high-temperature resistant slow-release foaming material is a porous aggregate of nanoparticles, and the particle size of the nanoparticles is preferably 20-100 nm, more preferably 20-50 nm; and / or, the porous aggregate of the nanoparticles has a mesoporous structure.

[0012] In a preferred embodiment of the present invention,

[0013] The mass ratio of the inorganic silica gel to the surfactant is 1:(0.8 - 18), preferably 1:(2.7 - 14), more preferably 1:(2.7 - 12.8).

[0014] In a preferred embodiment of the present invention,

[0015] The high-temperature resistant and slow-release foaming material further contains water. Based on the total weight of the high-temperature resistant and slow-release foaming material, the water content is 0.1 - 15 wt%, preferably 2 - 10 wt%.

[0016] In a preferred embodiment of the present invention,

[0017] The inorganic silica gel is obtained by hydrolysis and polycondensation of a silicon precursor. Preferably, the silicon precursor is at least one of silicate esters and silica sols, more preferably at least one of silicate esters, and further preferably at least one of tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate, and tetrabutyl silicate, and even more preferably tetraethyl silicate; the inorganic silica gel in the present invention is a heat-stable inorganic silicon-containing polymer; and / or,

[0018] The surfactant is at least one of cationic surfactants, amphoteric surfactants, and anionic surfactants; preferably, the cationic surfactant is at least one of alkyltrimethylammonium salts; and / or, the amphoteric surfactant is at least one of alkyl betaines, preferably at least one of alkylamidopropyl betaines; and / or, the anionic surfactant is at least one of alkylbenzenesulfonates and alkylsulfonates.

[0019] In a preferred embodiment of the present invention,

[0020] The alkyl chain lengths in the alkyltrimethylammonium salts, alkyl betaines, alkylbenzenesulfonates, and alkylsulfonates are each independently 8 - 16; preferably,

[0021] The surfactant is at least one of laurylamidopropyl betaine, cocamidopropyl betaine, and cetyltrimethylammonium salt.

[0022] In the present invention, the alkyl chain length refers to the length of the alkyl main chain. It can be understood that branches may or may not be connected to the alkyl main chain, and the present invention places no restrictions on the branches. For example, they can be alkyl branches, and those skilled in the art can freely choose as long as it is beneficial to improve the temperature resistance and slow-release performance of the composite material.

[0023] Other commonly used additives in the art, such as inert inorganic salts, etc., can also be added to the high-temperature resistant and slow-release foaming material of the present invention. The inert inorganic salt is preferably Na 2 SO 4Or NaCl, and their dosages are also conventional dosages, which can be added by those skilled in the art according to the actual situation.

[0024] In a preferred embodiment of the present invention,

[0025] The high-temperature resistant and slow-release foaming material is prepared by a step of mixing components including a silicon precursor and the surfactant followed by hydrolysis and polycondensation; preferably, the mass ratio of the surfactant to the silicon precursor is (0.25 - 5):1, preferably (0.8 - 4):1, and more preferably (0.8 - 3.7):1.

[0026] The second object of the present invention is to provide a preparation method of the high-temperature resistant and slow-release foaming material of the first object of the present invention, including a step of mixing components including a silicon precursor and the surfactant followed by hydrolysis and polycondensation; preferably, the mass ratio of the surfactant to the silicon precursor is (0.25 - 5):1, preferably (0.8 - 4):1, and more preferably (0.8 - 3.7):1.

[0027] In a preferred embodiment of the present invention,

[0028] The method includes:

[0029] Dissolve the surfactant in water, adjust the pH to alkaline, then add the silicon precursor and adjust the pH to acidic, and then carry out aging to obtain the high-temperature resistant and slow-release foaming material.

[0030] In a preferred embodiment of the present invention,

[0031] The mass ratio of the surfactant to water is 1:(1 - 10), preferably 1:(2 - 3); and / or,

[0032] After dissolving the surfactant in water, adjust the pH to 9 - 10, preferably adjusted by at least one of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate and their solutions; and / or,

[0033] After adding the silicon precursor, adjust the pH to 2 - 3, preferably adjusted by at least one of hydrochloric acid, sulfuric acid, acetic acid, oxalic acid and their solutions; and / or,

[0034] The aging conditions include: aging at a temperature of 40 - 80°C for 48 - 96 h, preferably aging by stepwise increasing the temperature, more preferably aging at 40 - 55°C for 1 - 12 h, at 55 - 65°C for 1 - 3 d, and at 65 - 80°C for 0.5 - 1.5 d.

[0035] A third object of the present invention is to provide an application of a high-temperature resistant and slow-release foaming material of one of the objects of the present invention or a high-temperature resistant and slow-release foaming material obtained by the preparation method of the second object of the present invention as a foam drainage agent.

[0036] In a preferred embodiment of the present invention,

[0037] When the high-temperature resistant and slow-release foaming material is used as a foam drainage agent, the application conditions include: wellbore temperature of 80-150 °C; and / or, pH of 4-5.

[0038] The temperature-resistant and slow-release foaming material provided by the present invention can slowly release active substances - surfactants under high-temperature wellbore conditions (such as 80-150 °C) and acidic conditions (such as pH of 4-5), and is used as a foaming agent.

[0039] The foaming agent carried in the temperature-resistant and slow-release foaming material of the present invention can be used for gas drainage and gas production in high-temperature gas wells, and solve the problem of frequent well opening and adding foam drainage agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is an external view of the high-temperature resistant and slow-release foaming material of Example 1;

[0041] Figure 2 It is an external view of the high-temperature resistant and slow-release foaming material of Example 2;

[0042] Figure 3 It is an external view of the high-temperature resistant and slow-release foaming material of Example 1 after 1-day slow-release evaluation;

[0043] Figure 4 It is an external view of the high-temperature resistant and slow-release foaming material of Example 1 after 3-day slow-release evaluation;

[0044] Figure 5 It is an external view of the high-temperature resistant and slow-release foaming material of Example 1 after 5-day slow-release evaluation;

[0045] Figure 6 It is an external view of the high-temperature resistant and slow-release foaming material of Example 1 after 7-day slow-release evaluation;

[0046] Figure 7 It is an external view of the high-temperature resistant and slow-release foaming material of Example 2 after 1-day slow-release evaluation;

[0047] Figure 8 It is an external view of the high-temperature resistant and slow-release foaming material of Example 2 after 3-day slow-release evaluation;

[0048] Figure 9 It is an external view of the high-temperature resistant and slow-release foaming material of Example 2 after 5-day slow-release evaluation;

[0049] Figure 10 Appearance diagram of the high-temperature resistant slow-release foaming material of Example 2 after 7 days of slow-release evaluation;

[0050] Figure 11 Microscopic SEM image of the high-temperature resistant slow-release foaming material of Example 1 containing CTAB before slow release;

[0051] Figure 12 Microscopic SEM image of the high-temperature resistant slow-release foaming material of Example 1 containing CTAB after 3 days of slow-release evaluation;

[0052] Figure 13 Microscopic SEM image of the high-temperature resistant slow-release foaming material of Example 2 containing CAB before slow release;

[0053] Figure 14 Microscopic SEM image of the high-temperature resistant slow-release foaming material of Example 2 containing CAB after 3 days of slow-release evaluation;

[0054] Figure 15 Scanning electron microscope surface element analysis diagram of the high-temperature resistant slow-release foaming material of Example 1 before slow release;

[0055] Figure 16 Scanning electron microscope surface element analysis diagram of the high-temperature resistant slow-release foaming material of Example 2 before slow release;

[0056] Figure 17 Scanning electron microscope surface element analysis diagram of the high-temperature resistant slow-release foaming material of Example 1 after 3 days of release;

[0057] Figure 18 Scanning electron microscope surface element analysis diagram of the high-temperature resistant slow-release foaming material of Example 2 after 3 days of release. Detailed implementation manners

[0058] The present invention will be specifically described below in conjunction with specific embodiments and the accompanying drawings. It is necessary to point out here that the following embodiments are only used for further illustration of the present invention and cannot be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention still fall within the protection scope of the present invention.

[0059] If there is no special limitation on the raw materials used in the embodiments, they are all disclosed in the prior art. For example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0060] The instrument used for thermogravimetric analysis in the embodiments is the Hitachi TG / DTA7200 thermogravimetric calorimeter dual analyzer in Japan.

[0061] Example 1

[0062] Mix 10 g of water and 4.0 g of cetyltrimethylammonium bromide (CTAB) at 25 °C with stirring for 15 min. Add NH 4 OH to adjust the pH to 9.5 and stir for 5 min; add 4.0 g of tetraethyl orthosilicate (TEOS) and stir at 25 °C for 15 min. Add 1 mol / L HCl to adjust the pH to 2.5. Age at 50 °C for 4 h, at 60 °C for 2 days, and at 75 °C for 1 day to form a gel solid block, which is the high-temperature resistant slow-release foaming material (as shown in Figure 1 ). The water content of the high-temperature resistant slow-release foaming material measured by thermogravimetry is 4.2 wt%.

[0063] Example 2

[0064] Mix 10 g of water and 4.0 g of lauramidopropyl betaine (CAB) at 25 °C with stirring for 15 min. Add NH 4 OH to adjust the pH to 9.5 and stir for 5 min; add 4.0 g of tetraethyl orthosilicate (TEOS) and stir at 25 °C for 15 min. Adjust the pH to 2.5 with 1 mol / L HCl. Age at 50 °C for 4 h, at 60 °C for 2 days, and at 75 °C for 1 day to form a gel solid block, which is the high-temperature resistant slow-release foaming material (as shown in Figure 2 ). The water content of the high-temperature resistant slow-release foaming material measured by thermogravimetry is 8.5 wt%.

[0065] Evaluation of the surfactant release efficiency after the release of Examples 1-2

[0066] The slow-release evaluation experiment is as follows: Put 4.5 g of the high-temperature resistant slow-release foaming materials of Examples 1-2 into a pressure-resistant bottle containing 60 mL of simulated underground brine and seal it. The components of the simulated underground brine are: calcium chloride 8.37 g / L, magnesium chloride 0.42 g / L, sodium sulfate 1.21 g / L, sodium chloride 60.74 g / L. Pass carbon dioxide into the simulated underground brine until it is saturated to simulate the downhole acidic environment, and the pH is 4 at this time. Conduct the experiment at a constant temperature of 130 °C. During this period, replace the simulated underground brine saturated with carbon dioxide every 24 hours and observe whether the sample maintains its appearance and shape. The appearances of the high-temperature resistant slow-release foaming material of Example 1 after 1, 3, 5, and 7 days of slow-release evaluation are as shown in Figures 3 - 6 . The appearances of the high-temperature resistant slow-release foaming material of Example 2 after 1, 3, 5, and 7 days of slow-release evaluation are as shown in Figures 7 - 10 . It can be seen that after 7 days in high-temperature brine, the solid of the high-temperature resistant slow-release foaming material releases and decomposes and gradually shrinks.

[0067] For the post-release surfactants of Examples 1-2, their release efficacy was evaluated by testing their foam volume and half-life performance: 40 mL of the solutions released in 1-7 days were respectively taken and diluted with water to prepare 200 mL of standard solutions, which were foamed by the stirring method. A stirrer was used for foaming, the rotation speed was set at 16,000 rpm, and the stirring time was 30 seconds. The foam volume was measured, and the results are shown in Table 1.

[0068] Table 1

[0069] Time Example 1 (ml) Example 2 (ml) Day 1 400 410 Day 2 345 310 Day 3 310 290 Day 4 285 260 Day 5 260 225 Day 6 255 218 Day 7 235 205

[0070] As can be seen from Table 1: The high-temperature resistant sustained-release foaming materials of Examples 1-2 can maintain the release of surfactants for more than 72 hours, indicating good sustained-release performance.

[0071] Example 3

[0072] A series of high-temperature resistant sustained-release foaming materials (including the high-temperature resistant sustained-release foaming materials of Examples 1 and 2) as described in Table 2 were prepared by mixing surfactants and silicon precursors in different mass ratios. The preparation conditions were the same as those in Example 1.

[0073] Table 2

[0074]

[0075] As can be seen from Table 2, only when the mass ratio of the surfactant to the silicon precursor is preferably in the range of (0.8-4):1, more preferably in the range of (0.8-3.7):1, and further preferably in the range of (1-3.7):1, can the high-temperature resistant sustained-release foaming material be formed into a relatively hard and complete solid. Outside this range, only soft wet gels or unformed fragments can be obtained. The wet gels are easy to adhere to the wellbore wall, the unformed fragments are not convenient to be injected into the wellbore, and are easy to be carried out of the wellbore by the gas flow, failing to achieve the sustained-release effect.

[0076] Example 4

[0077] The initial and post-release evaluation of the high-temperature resistant sustained-release foaming materials of Examples 1 and 2 after 3 days was characterized by their microstructures, as Figures 11 - 14 shown: The SEM microstructure shows that the high-temperature resistant sustained-release foaming material contains a porous aggregate of nanoparticles with a particle size of 20-100 nm, preferably 20-50 nm. This aggregate structure contains a mesoporous structure, forming a channel for the controlled release of surfactants. The surface element analysis (EDS) of the initial and post-release foaming materials of Examples 1 and 2 after 3 days was carried out, as Figures 15 - 18 shown: The surface element analysis (EDS) shows that the initial high-temperature resistant sustained-release foaming material has the characteristic elements C, N, and Br of the corresponding surfactant, as Figure 15 and 16; After 3 days of release, the voids increase and the structure becomes loose. The content of the characteristic elements of the surfactant decreases, and the content of silicon elements increases, such as Figure 17 and 18 .

[0078] The endpoints and any values in the ranges disclosed in this document are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the values between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this document.

[0079] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A high-temperature resistant and slow-release foaming material, comprising inorganic silica gel and a surfactant.

2. The high-temperature resistant and slow-release foaming material according to claim 1, characterized in that: the high-temperature resistant and slow-release foaming material is a porous aggregate of nanoparticles, the particle size of the nanoparticles is preferably 20-100 nm, more preferably 20-50 nm; and / or, the porous aggregate of the nanoparticles has a mesoporous structure.

3. The high-temperature resistant and slow-release foaming material according to claim 1, characterized in that: the mass ratio of the inorganic silica gel to the surfactant is 1:(0.8-18), preferably 1:(2.7-14), more preferably 1:(2.7-12.8).

4. The high-temperature resistant and slow-release foaming material according to claim 1, characterized in that: the inorganic silica gel is obtained by hydrolysis and polycondensation of a silicon precursor. Preferably, the silicon precursor is at least one of silicate esters and silica sols, preferably at least one of silicate esters, more preferably at least one of tetramethyl silicate, tetraethyl silicate, tetrapropyl silicate, and tetrabutyl silicate; and / or, the surfactant is at least one of cationic surfactants, amphoteric surfactants, and anionic surfactants; preferably, the cationic surfactant is at least one of alkyltrimethylammonium salts; and / or, the amphoteric surfactant is at least one of alkyl betaines, preferably at least one of alkylamidopropyl betaines; and / or, the anionic surfactant is at least one of alkylbenzene sulfonates and alkyl sulfonates.

5. The high-temperature resistant and slow-release foaming material according to claim 4, characterized in that: the alkyl chain lengths of the alkyltrimethylammonium salts, alkyl betaines, alkylbenzene sulfonates, and alkyl sulfonates are each independently 8-16; preferably, the surfactant is at least one of dodecylamidopropyl betaine, coconut oil amidopropyl betaine, and cetyltrimethylammonium salt.

6. The high-temperature resistant and slow-release foaming material according to any one of claims 1-5, characterized in that: the high-temperature resistant and slow-release foaming material is prepared by a step of mixing components including a silicon precursor and the surfactant and then performing hydrolysis and polycondensation; preferably, the mass ratio of the surfactant to the silicon precursor is (0.25-5):1, preferably (0.8-4):1, more preferably (0.8-3.7):

1.

7. A preparation method of the high-temperature resistant and slow-release foaming material according to any one of claims 1-6, comprising a step of mixing components including a silicon precursor and the surfactant and then performing hydrolysis and polycondensation; preferably, the mass ratio of the surfactant to the silicon precursor is (0.25-5):1, preferably (0.8-4):1, more preferably (0.8-3.7):

1.

8. The preparation method according to claim 7, characterized in that the method comprises: dissolving the surfactant in water, adjusting the pH to alkaline, then adding the silicon precursor and adjusting the pH to acidic, and then aging to obtain the high-temperature resistant and slow-release foaming material.

9. The preparation method according to claim 8, It is characterized in that: The mass ratio of the surfactant to water is 1:(1-10), preferably 1:(2-3); and / or, After dissolving the surfactant in water, the pH is adjusted to 9-10, preferably adjusted by at least one of ammonia water, sodium hydroxide, potassium hydroxide, sodium carbonate and their solutions; and / or, After adding the silicon precursor, the pH is adjusted to 2-3, preferably adjusted by at least one of hydrochloric acid, sulfuric acid, acetic acid, oxalic acid and their solutions; and / or, The aging conditions include: aging at a temperature of 40-80°C for 48-96 h, preferably aging by stepwise heating, more preferably aging at 40-55°C for 1-12 h, aging at 55-65°C for 1-3 d, and aging at 65-80°C for 0.5-1.5 d.

10. Use of a high-temperature resistant and slow-release foaming material as claimed in any one of claims 1-6 or a high-temperature resistant and slow-release foaming material obtained by the preparation method as claimed in any one of claims 7-9 as a foam drainage agent.

11. The use as claimed in claim 10, It is characterized in that: When the high-temperature resistant and slow-release foaming material is used as a foam drainage agent, the application conditions include: wellbore temperature of 80-150°C; and / or, pH of 4-5.

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