High-temperature-resistant toughening agent as well as preparation method and application thereof in oil well
By coating the fiber with polyarylsulfone and optimizing the mass ratio of fiber to whiskers, the problem of poor toughening effect of existing toughening agents under high temperature conditions is solved, and the high temperature toughening effect of the toughening agent and the tensile strength of the cement ring are significantly improved.
Patent Information
- Application Number
- CN202510191179.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-20
- Publication Date
- 2025-05-16
AI Technical Summary
The existing toughening agents have poor toughening effect under high temperature conditions, resulting in brittle damage of the cement ring during casing pressure test, fracturing and perforation, and lose the interlayer sealing ability.
Polyaryl sulfone-coated fibers are used as toughening agents. By optimizing the mass ratio of whiskers to fibers to 1.5~2:1, the surface area and roughness of the fiber surface are improved, thereby enhancing the high-temperature toughening effect of the toughening agent.
It significantly improves the high-temperature toughening effect of the toughening agent, enhances the tensile strength and impact resistance of the cement ring, avoids brittle damage, and ensures the interlayer sealing ability.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of cementing materials, and in particular to a high temperature resistant toughening agent and a preparation method thereof and application in oil wells. Background Art
[0002] Oil well cement refers to silicate cement and non-Silicate cement used for cementing, well repair, squeezing and other operations under various drilling conditions, including oil well cement systems of modified cement or special cement mixed with various admixtures.
[0003] The construction conditions of cementing oil and gas wells are different from those of silicate cement used in construction, hydraulic engineering, marine engineering, tunnels, and tunnels. The geological environment of oil and gas wells is very complex, and there are many types of wells, which makes the use temperature range of cementing cement extremely wide. In addition, conventional cement stone is brittle and has poor impact load resistance. During the operation of casing pressure testing, fracturing and perforating, the cement ring is prone to brittle failure and loses its interlayer isolation ability. Therefore, it is necessary to add toughening agents to the cement slurry, but the high temperature toughening effect of existing toughening agents is not ideal. Summary of the invention
[0004] The invention provides a high temperature resistant toughening agent and a preparation method thereof and application in oil wells, which solves the problem of poor high temperature resistant toughening effect of the toughening agent in the related art.
[0005] The technical solution of the present invention is as follows: The high temperature resistant toughening agent is polyarylsulfone coated fiber.
[0006] As a further technical solution, the raw material of the polyarylsulfone coated fiber includes polyarylsulfone and fiber in a mass ratio of 1 to 3:10.
[0007] As a further technical solution, the fiber includes one or more of carbon fiber, glass fiber, and steel fiber.
[0008] As a further technical solution, whiskers are also included, and the mass ratio of the whiskers to the fibers is 1-2.5:1.
[0009] In the present invention, whiskers are further added and coated on the fiber surface through polyarylsulfone as a medium, which not only increases the surface area of the fiber, but also improves the surface roughness of the fiber and increases the friction, thereby further improving the high temperature resistant toughening effect of the toughening agent.
[0010] As a further technical solution, the mass ratio of the whiskers to the fibers is 1.5-2:1.
[0011] In the present invention, the mass ratio of whiskers to fibers is optimized to 1.5-2:1, which further improves the high temperature resistant toughening effect of the toughening agent. When the amount of whiskers used is less than this range, too few whiskers are coated on the fiber surface, resulting in a decrease in the toughening effect. On the contrary, when the amount of whiskers used exceeds this range, the whiskers are unevenly dispersed in the polyarylsulfone solution and agglomerate, resulting in an unsatisfactory coating effect of the whiskers on the fiber surface, which also leads to a decrease in the toughening effect.
[0012] As a further technical solution, the whiskers include one or more of four-needle zinc oxide whiskers, silicon carbide whiskers, and potassium titanate whiskers.
[0013] The present invention also proposes a method for preparing the high temperature resistant toughening agent, comprising the following steps: A1. After dissolving the polyarylsulfone, add the whiskers and disperse them evenly to obtain an impregnation solution; A2. After the fiber is immersed in the impregnating liquid, it is dried to obtain a high temperature resistant toughening agent.
[0014] In step A1 of the present invention, the solvent used for dissolving may be any one or more solvents that can dissolve polyarylsulfone, preferably one or two of N,N-dimethylformamide and N,N-dimethylacetamide.
[0015] As a further technical solution, the mass ratio of the solvent to the fiber is 10~20:1.
[0016] The present invention also proposes the use of the high temperature resistant toughening agent or the high temperature resistant toughening agent prepared by the preparation method in oil wells.
[0017] The working principle and beneficial effects of the present invention are: In the present invention, polyarylsulfone coated fiber is used as a toughening agent. After the fiber is coated with polyarylsulfone, the surface wetting properties of the fiber can be improved and the problem of uneven mixing can be improved due to the hydrophilic ether bonds and sulfone groups of polyarylsulfone, thereby improving the high temperature resistant toughening effect of the toughening agent. DETAILED DESCRIPTION
[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0019] The parameters of the raw materials in the following examples and comparative examples are as follows: The brand of polyarylsulfone is Astrel360; The length of the four-needle zinc oxide whiskers is 10~50um and the diameter is 0.5~5um; The glass fiber has a length of 3 mm and a diameter of 13 μm; The carbon fiber has a length of 0.8 mm and a diameter of 7 μm.
[0020] Example 1 A1, dissolving 1 part of polyarylsulfone in 100 parts of DMF to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 5 minutes and then dry to obtain a high temperature resistant toughening agent.
[0021] Example 2 A1, dissolving 3 parts of polyaryl sulfone in 200 parts of DMAc to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 3 minutes and then dry to obtain a high temperature resistant toughening agent.
[0022] Example 3 A1. Dissolve 1 part of polyarylsulfone in 100 parts of DMF, add 10 parts of tetrapod-shaped zinc oxide whiskers and disperse them evenly by ultrasonic to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 5 minutes and then dry to obtain a high temperature resistant toughening agent.
[0023] Example 4 A1, dissolving 1 part of polyarylsulfone in 100 parts of DMF to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 5 minutes, dry, add 10 parts of tetrapod-shaped zinc oxide whiskers and mix evenly to obtain a high temperature resistant toughening agent.
[0024] Example 5 A1. Dissolve 1 part of polyarylsulfone in 100 parts of DMF, add 15 parts of tetrapod-shaped zinc oxide whiskers and disperse them evenly by ultrasonic to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 5 minutes and then dry to obtain a high temperature resistant toughening agent.
[0025] Example 6 A1. Dissolve 1 part of polyarylsulfone in 100 parts of DMF, add 20 parts of tetrapod-shaped zinc oxide whiskers and disperse them evenly by ultrasonic to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 5 minutes and then dry to obtain a high temperature resistant toughening agent.
[0026] Example 7 A1. Dissolve 1 part of polyarylsulfone in 100 parts of DMF, add 25 parts of tetrapod-shaped zinc oxide whiskers and disperse them evenly by ultrasonic to obtain an impregnation solution; A2. Immerse 10 parts of fibers (glass fiber and carbon fiber in a mass ratio of 3:2) in the above impregnation solution for 5 minutes and then dry to obtain a high temperature resistant toughening agent.
[0027] Comparative Example 1 10 parts of fibers (glass fibers and carbon fibers in a mass ratio of 3:2) and 1 part of polyarylsulfone were uniformly mixed to obtain a high temperature resistant toughening agent.
[0028] Performance Test: The toughening agents obtained in Examples 1 to 7 and Comparative Example 1 were tested for performance according to the methods in GB / T 19139-2012 and NB / T 14004.2-2016. The formula was: G-grade oil well cement + 35% quartz sand + 1.5% BFR-30L oil well cement dispersant + 5% BFL-12L oil well cement fluid loss reducer + 0.5% toughening agent + 2.5% oil well cement retarder SN-2 + water (% refers to the mass of cement), water-cement ratio was 0.44, thickening temperature was 180°C, and curing temperature was 240°C. The test results are recorded in Tables 1 and 2.
[0029] Table 1 Toughener performance test results
[0030] It can be seen from Table 1 that, compared with Comparative Example 1, the 3d tensile strength of the cement prepared by the toughening agent obtained in Examples 1 to 7 is above 4.11 MPa, and the 7d tensile strength is above 4.47 MPa, indicating that the high temperature resistant toughening effect of the toughening agent can be improved after the fiber is coated with polyarylsulfone.
[0031] Table 2 Toughener performance test results
[0032] It can be seen from Table 2 that the high temperature resistant toughening agent provided by the present invention will not have a negative impact on the engineering properties of cement paste, can be used in practice, and broadens the application field of the toughening agent.
[0033] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A high temperature resistant toughening agent, characterized in that: It is a polyarylsulfone coated fiber.
2. The high temperature resistant toughening agent according to claim 1, characterized in that: The raw materials of the polyarylsulfone coated fiber include polyarylsulfone and fiber in a mass ratio of 1 to 3:
10.
3. The high temperature resistant toughening agent according to claim 2, characterized in that: The fibers include one or more of carbon fibers, glass fibers, and steel fibers.
4. The high temperature resistant toughening agent according to claim 2, characterized in that: It also includes whiskers, and the mass ratio of the whiskers to the fibers is 1-2.5:
1.
5. The high temperature resistant toughening agent according to claim 4, characterized in that: The mass ratio of the whiskers to the fibers is 1.5 to 2:
1.
6. The high temperature resistant toughening agent according to claim 4, characterized in that: The whiskers include one or more of tetrapod-shaped zinc oxide whiskers, silicon carbide whiskers, and potassium titanate whiskers.
7. The method for preparing the high temperature resistant toughening agent according to claim 6, characterized in that: The following steps are involved: A1. After dissolving the polyarylsulfone, add the whiskers and disperse them evenly to obtain an impregnation solution; A2. After the fiber is immersed in the impregnating liquid, it is dried to obtain a high temperature resistant toughening agent.
8. The method for preparing the high temperature resistant toughening agent according to claim 7, characterized in that: In step A1, the solvent used for dissolving is one or both of DMF and DMAc.
9. The method for preparing the high temperature resistant toughening agent according to claim 8, characterized in that: The mass ratio of the solvent to the fiber is 10-20:
1.
10. Use of the high temperature resistant toughening agent according to any one of claims 1 to 6 or the high temperature resistant toughening agent prepared by the preparation method according to any one of claims 7 to 9 in oil wells.