Preparation method, product and application of polyacrylonitrile fiber modified polyurea material
By modifying polyacrylonitrile fibers and combining them with polyurea materials, high-performance sprayed polyurea materials were prepared, which solved the problem of poor hydrophobic and mechanical properties of existing polyurea materials in power transmission pole tower applications, and significantly improved the overall performance and application safety of the material.
Patent Information
- Application Number
- CN202510229845.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2025-06-13
AI Technical Summary
In the application of existing polyurea materials in power transmission pole towers, the hydrophobic and mechanical properties are poor, and it is prone to fouling accidents.
High-performance sprayed polyurea material is prepared by modifying polyacrylonitrile fibers and combining them with polyurea materials. The method includes reacting ethylenediamine with polyacrylonitrile fibers, adding concentrated sulfuric acid and potassium dichromate for amination treatment, and then reacting with components such as polyetheramine and isocyanate to form a fiber-modified polyurea solution.
It significantly improves the mechanical properties and weather resistance of polyurea materials, improves its hydrophobic properties, reduces the water absorption rate, reduces the probability of fouling accidents, and reduces the cost of engineering applications.
Smart Images
Figure CN120137140A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a spraying material for local insulation of a power transmission tower in an electric power system, and in particular to a preparation method, a product and an application of a polyurea material modified with polyacrylonitrile fiber. Background Art
[0002] As for the spraying materials for transmission line towers, due to their extreme use environment, traditional spraying materials such as alkyd resin and acrylic resin are difficult to meet the strict requirements of coating life and grid safety. As a high-performance elastomer, polyurea is prepared by polymerization of isocyanate components and amino resin components. Its molecular chain is rich in repeating units of urea groups (-NHCONH-). It has high wear resistance, corrosion resistance and excellent mechanical properties, and is green and environmentally friendly, fast curing, short construction cycle, and uses low-solvent or solvent-free formulas. It has attracted much attention. However, the polyurea materials currently used have poor hydrophobicity and mechanical properties. When used in transmission towers, flashover accidents are prone to occur. Summary of the invention
[0003] In view of the problems existing in the above-mentioned prior art, the present invention provides a method for preparing a polyurea material modified with polyacrylonitrile fiber, thereby solving the problems of poor hydrophobicity and mechanical properties of the polyurea material in the prior art.
[0004] Another object of the present invention is to provide a polyurea material modified with polyacrylonitrile fibers.
[0005] Another object of the present invention is to provide an application of polyurea material modified with polyacrylonitrile fiber.
[0006] The technical scheme of the present invention is as follows:
[0007] A method for preparing a polyurea material modified with polyacrylonitrile fiber comprises the following steps:
[0008] After adding ethylenediamine into deionized water and stirring sufficiently, adding polyacrylonitrile fiber into the ethylenediamine solution to react to obtain pre-modified polyacrylonitrile fiber, adding concentrated sulfuric acid and potassium dichromate to the pre-modified polyacrylonitrile fiber, and then washing and drying to obtain aminated polyacrylonitrile fiber;
[0009] Dissolving polyetheramine PEA and polyetheramine D2000 in tetrahydrofuran to obtain a blocking agent solution; dissolving toluene diisocyanate and dicyclohexylmethane-4,4'-diisocyanate in tetrahydrofuran to obtain an isocyanate solution, and adding the isocyanate solution dropwise to the blocking agent solution for sufficient reaction to obtain a polyurea prepolymer;
[0010] Add the amidated polyacrylonitrile fiber to the polyurea prepolymer and stir evenly to obtain a reaction mixture; dissolve 2-aminophenylboronic acid and diethyltoluenediamine in tetrahydrofuran to obtain Auxiliary A, and dropwise add Auxiliary A to the reaction mixture and react fully to obtain a fiber-modified polyurea solution.
[0011] Further, in the step of preparing the amidated polyacrylonitrile fiber, the mass-volume ratio (g / mL) of ethylenediamine, polyacrylonitrile fiber to deionized water is 10-30:4-10:150-250.
[0012] Further, in the step of preparing the amidated polyacrylonitrile fiber, the mass-volume ratio (g / mL) of polyacrylonitrile fiber to concentrated sulfuric acid and potassium dichromate is 4-10:7-15:7-15.
[0013] Further, in the step of preparing the amidated polyacrylonitrile fiber, the polyacrylonitrile fiber and ethylenediamine solution are sealed and reacted in a blast drying oven at 80-120 °C for 20-28 h.
[0014] Further, in the step of preparing the polyurea prepolymer, the mass-volume ratio (g / mL) of polyetheramine PEA, polyetheramine D2000 to tetrahydrofuran is 25-45:30-50:80-120.
[0015] Further, in the step of preparing the polyurea prepolymer, the mass-volume ratio (g / mL) of toluene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate to tetrahydrofuran is 30-50:50-70:70-90.
[0016] Further, in the step of preparing the polyurea prepolymer, the reaction time of the isocyanate solution and the capping agent solution at 50-60 °C is 20-28 h; the preheating treatment condition for preparing the capping agent solution is preheating treatment at 40-50 °C for 30-50 min.
[0017] Further, in the step of preparing the fiber-modified polyurea, the mass fraction ratio of the amidated polyacrylonitrile fiber to the polyurea prepolymer is 1-5:100.
[0018] Further, in the step of preparing the fiber-modified polyurea, in the Auxiliary A, the mass-volume ratio (g / mL) of 2-aminophenylboronic acid, diethyltoluenediamine to tetrahydrofuran is 8-12:5-9:30-50.
[0019] Further, in the step of preparing the fiber-modified polyurea, when dropping Auxiliary A into the reaction mixture, the dropping time is 50-70 min and the reaction temperature is 40-60 °C.
[0020] Further, in the step of preparing the fiber-modified polyurea, the addition of a catalyst is also included, and the catalyst is dibutyltin dilaurate.
[0021] Further, a fiber-modified polyurea material product obtained by the above preparation method.
[0022] Further, the application of the fiber-modified polyurea solution in the spraying material for transmission towers.
[0023] Further, the fiber-modified polyurea solution is removed of the solvent by rotary evaporation until it becomes viscous. The viscous fiber-modified polyurea solution is inverted on a polytetrafluoroethylene mold and dried in vacuum to obtain the spraying material for transmission towers.
[0024] The advantages and effects of the present invention are as follows:
[0025] In the present invention, the properties of polyacrylonitrile fibers are modified, and they are well combined with the polyurea material. Utilizing the characteristics of polyacrylonitrile fibers, a high-performance sprayed polyurea material is prepared. Through the role of polyacrylonitrile fibers in the polyurea material, the mechanical properties, weather resistance, and water absorption of the polyurea material are effectively improved. In this process, polyacrylonitrile fibers play a crucial role in the polyurea material with their fiber structure and enhanced properties after modification. It can not only effectively enhance the overall mechanical properties of the polyurea material, making the polyurea material show more excellent stability and durability when subjected to external forces. At the same time, the addition of polyacrylonitrile fibers also significantly reduces the water absorption of the polyurea material, enabling the polyurea material to have a larger contact angle and maintain good hydrophobic properties; moreover, polypropylene fibers have good economy, greatly reducing the cost of engineering applications.
[0026] At the same time, toluene diisocyanate (TDI) and dicyclohexylmethane-4,4'-diisocyanate (HMDI) are selected as the isocyanate raw materials, making the prepared polyurea have better mechanical properties and mechanical performance. Dibutyltin dilaurate (DBTDL, 95%) is selected as the catalyst for the reaction to accelerate the reaction rate and improve the curing speed. Description of the Drawings
[0027] Figure 1 is a schematic diagram of the breakdown voltage change of the polyurea material before modification;
[0028] Figure 2 is a schematic diagram of the breakdown voltage change of the polyurea material after modification;
[0029] Figure 3 is a schematic diagram of the mechanical property change of the polyurea material before modification;
[0030] Figure 4 is a schematic diagram of the mechanical property change of the polyurea material after modification;
[0031] Figure 5 It is a schematic diagram of the change in the hydrophobic property of the polyurea material before modification;
[0032] Figure 6 It is a schematic diagram of the change in the hydrophobic property of the modified polyurea material. Specific implementation manner
[0033] Example 1
[0034] Add 21 g of ethylenediamine to 200 ml of deionized water, stir well for 3 hours, put it into a reaction kettle, add 7 g of vacuum-dried polyacrylonitrile fiber to the solution system and disperse it evenly by ultrasonic wave. The ultrasonic dispersion frequency is 20 kHz and the dispersion time is 15 min. Seal the reaction kettle and place it in a blast drying oven at 100 °C for reaction for 24 h. After the reaction is completed, obtain the pre-modified polyacrylonitrile fiber. Wait for the reaction kettle to cool to room temperature, open the reaction kettle, take out all the obtained pre-modified polyacrylonitrile fiber and add 10 ml of concentrated sulfuric acid (H 2 SO 4 ), and 10 ml of potassium dichromate (K 2 Cr 2 O 7 ). Wash it with deionized water at 25 °C until neutral, and then wash it with absolute ethanol 5 times. After air-drying at room temperature, dry it in a vacuum drying oven at 70 °C for 12 h to obtain light yellow aminated polyacrylonitrile fiber.
[0035] Dissolve 35 g of polyetheramine PEA (PEA represents the model) and 40 g of polyetheramine D2000 (D2000 has a molecular weight of 2000 g / mol) in 100 ml of tetrahydrofuran, put it into a three-necked flask and preheat it at 45 °C for 45 min, and then cool it to room temperature to obtain a capping agent solution. Dissolve 40 g of toluene diisocyanate (TDI) and 60 g of dicyclohexylmethane-4,4'-diisocyanate (HMDI) in 80 mL of tetrahydrofuran to obtain an isocyanate solution. Dropwise add the isocyanate solution to the capping agent solution and stir continuously. The reaction time at 55 °C is 24 h; obtain a polyurea prepolymer.
[0036] Add 3 g of the aminated polyacrylonitrile fiber to 100 g of the polyurea prepolymer, stir it with a planetary stirrer for 10 min to obtain a reaction mixture; weigh 10 g of 2-aminophenylboronic acid and 8 g of diethyltoluenediamine, dissolve them in 40 ml of tetrahydrofuran to obtain additive A. Dropwise add additive A to the reaction mixture through a dropping funnel and stir continuously. The dropping time is 60 min, the reaction temperature is 55 degrees Celsius, and the catalyst dibutyltin dilaurate (DBTDL, 95%) is used to accelerate the reaction. The catalyst is added dropwise with a 50 ml polytetrafluoroethylene constant pressure separating funnel for 1 - 2 drops; obtain a fiber-modified polyurea solution.
[0037] The fiber-modified polyurea material product obtained by the above preparation method.
[0038] The above fiber-modified polyurea solution was removed of the solvent by rotary evaporation until it became viscous. The viscous fiber-modified polyurea solution was inverted onto a polytetrafluoroethylene mold and dried in a vacuum drying oven at 50 °C for 24 h to obtain the spraying material for transmission towers.
[0039] Example 2
[0040] In the step of preparing the aminated polyacrylonitrile fiber, the mass-volume ratio of ethylenediamine, polyacrylonitrile fiber and deionized water is: 10 g of ethylenediamine, 4 g of polyacrylonitrile fiber, and 150 mL of deionized water; the mass-volume ratio of the polyacrylonitrile fiber raw material, concentrated sulfuric acid and potassium dichromate is: 4 g of polyacrylonitrile fiber, 7 mL of concentrated sulfuric acid, and 7 mL of potassium dichromate.
[0041] The acrylonitrile fiber and the ethylenediamine solution were sealed and reacted in a blast drying oven at 80 °C for 28 h; the operating temperature during washing with deionized water was 20 °C; during washing with absolute ethanol, the number of washing times was 7 times; in the step of air-drying at room temperature, it was dried in a vacuum drying oven at 60 °C for 20 hours.
[0042] Other steps are the same as those in Example 1.
[0043] Example 3
[0044] In the step of preparing the aminated polyacrylonitrile fiber, the mass-volume ratio of ethylenediamine, polyacrylonitrile fiber and deionized water is: 30 g of ethylenediamine, 10 g of polyacrylonitrile fiber, and 250 mL of deionized water; the mass-volume ratio of the polyacrylonitrile fiber raw material, concentrated sulfuric acid and potassium dichromate is: 10 g of polyacrylonitrile fiber, 15 mL of concentrated sulfuric acid, and 15 mL of potassium dichromate.
[0045] The acrylonitrile fiber and the ethylenediamine solution were sealed and reacted in a blast drying oven at 120 °C for 20 h; the operating temperature during washing with deionized water was 30 °C; during washing with absolute ethanol, the number of washing times was 3 times; in the step of air-drying at room temperature, it was dried in a vacuum drying oven at 80 °C for 1 hour.
[0046] Other steps are the same as those in Example 1.
[0047] Example 4
[0048] In the preparation step of the polyurea prepolymer, the mass-to-volume ratios of polyetheramine PEA, polyetheramine D2000 and tetrahydrofuran are as follows: 25 g of polyetheramine PEA, 30 g of polyetheramine D2000, and 80 mL of tetrahydrofuran; the mass-to-volume ratios of toluene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate and tetrahydrofuran are as follows: 30 g of toluene diisocyanate, 50 g of dicyclohexylmethane-4,4'-diisocyanate, and 70 mL of tetrahydrofuran.
[0049] The reaction time of the isocyanate solution and the capping agent solution at 50 °C is 28 h; the preheating treatment condition for preparing the capping agent solution is preheating treatment at 40 °C for 50 min.
[0050] Other steps are the same as those in Example 1.
[0051] Example 5
[0052] In the preparation step of the polyurea prepolymer, the mass-to-volume ratios of polyetheramine PEA, polyetheramine D2000 and tetrahydrofuran are as follows: 45 g of polyetheramine PEA, 50 g of polyetheramine D2000, and 120 mL of tetrahydrofuran; the mass-to-volume ratios of toluene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate and tetrahydrofuran are as follows: 50 g of toluene diisocyanate, 70 g of dicyclohexylmethane-4,4'-diisocyanate, and 90 mL of tetrahydrofuran.
[0053] The reaction time of the isocyanate solution and the capping agent solution at 60 °C is 20 h; the preheating treatment condition for preparing the capping agent solution is preheating treatment at 50 °C for 30 min.
[0054] Other steps are the same as those in Example 1.
[0055] Example 6
[0056] In the step of preparing the fiber-modified polyurea, the masses of the aminated polyacrylonitrile fiber and the polyurea prepolymer are as follows: 1 g of aminated polyacrylonitrile fiber and 100 g of polyurea prepolymer. In the auxiliary agent A, the mass-to-volume ratios of 2-aminophenylboronic acid, diethyltoluenediamine and tetrahydrofuran are as follows: 8 g of 2-aminophenylboronic acid, 5 g of diethyltoluenediamine, and 30 mL of tetrahydrofuran; when the auxiliary agent A is added dropwise to the reaction mixture, the dropping time is 50 min and the reaction temperature is 40 °C.
[0057] Other steps are the same as those in Example 1.
[0058] Example 7
[0059] In the step of preparing the fiber-modified polyurea, the masses of the aminated polyacrylonitrile fiber and the polyurea prepolymer are 5 g of the aminated polyacrylonitrile fiber and 100 g of the polyurea prepolymer. In the auxiliary agent A, the mass-volume of 2-aminophenylboronic acid, diethyltoluenediamine and tetrahydrofuran is 12 g of 2-aminophenylboronic acid, 9 g of diethyltoluenediamine and 50 mL of tetrahydrofuran. When the auxiliary agent A is added dropwise to the reaction mixture, the dropping time is 70 min and the reaction temperature is 60 °C.
[0060] Other steps are the same as those in Example 1.
[0061] The technical effects of the present invention are further described by Figures 1-6 From the Figure 1 and Figure 2 before-and-after comparison breakdown voltage histogram shown, it can be found that the breakdown voltage of the modified polyurea material has increased significantly, fully meeting the breakdown voltage requirements for partial insulation.
[0062] From the Figure 3 and Figure 4 before-and-after comparison tensile strength histogram shown, it can be found that the tensile strength of the modified polyurea material has increased significantly. After modification, it has increased to a maximum of 20.6 MPa and a minimum of 17.4 MPa, which is greater than the highest tensile strength before modification, indicating that the polyacrylonitrile fiber effectively improves the mechanical properties of the polyurea material.
[0063] From the Figure 5 and Figure 6 before-and-after comparison water absorption rate histogram shown, it can be found that the water absorption rate of the modified polyurea material has decreased significantly. The water absorption rate represents its hydrophobic property. After the material is modified, it can achieve a very small water absorption rate, greatly reducing the probability of flashover accidents on transmission towers.
[0064] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a reference structure" does not exclude the existence of additional identical elements in the process, method, article or device including the element.
[0065] Although embodiments of the present invention have been shown and described, those of ordinary skill in the art will appreciate that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a polyurea material modified with polyacrylonitrile fiber, characterized in that: The steps include: After adding ethylenediamine into deionized water and stirring sufficiently, adding polyacrylonitrile fiber into the ethylenediamine solution to react and obtain pre-modified polyacrylonitrile fiber, adding concentrated sulfuric acid and potassium dichromate to the pre-modified polyacrylonitrile fiber, and then washing and drying to obtain aminated polyacrylonitrile fiber; Dissolving polyetheramine PEA and polyetheramine D2000 in tetrahydrofuran to obtain a blocking agent solution; dissolving toluene diisocyanate and dicyclohexylmethane-4,4'-diisocyanate in tetrahydrofuran to obtain an isocyanate solution, and adding the isocyanate solution dropwise to the blocking agent solution for sufficient reaction to obtain a polyurea prepolymer; The aminated polyacrylonitrile fiber is added to the polyurea prepolymer and stirred evenly to obtain a reaction mixture; 2-aminophenylboric acid and diethyltoluenediamine are dissolved in tetrahydrofuran to obtain an auxiliary agent A, and the auxiliary agent A is added dropwise to the reaction mixture to react fully to obtain a fiber-modified polyurea solution.
2. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing the aminated polyacrylonitrile fiber, the mass volume ratio (g / mL) of ethylenediamine, polyacrylonitrile fiber and deionized water is 10-30:4-10:150-250.
3. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing aminated polyacrylonitrile fiber, the mass volume ratio (g / mL) of polyacrylonitrile fiber to concentrated sulfuric acid and potassium dichromate is 4-10:7-15:7-15.
4. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing the aminated polyacrylonitrile fiber, the polyacrylonitrile fiber and the ethylenediamine solution are sealed and placed in a blast drying oven at 80-120° C. to react for 20-28 hours.
5. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing the polyurea prepolymer, the mass volume ratio (g / mL) of polyetheramine PEA, polyetheramine D2000 and tetrahydrofuran is 25-45:30-50:80-120.
6. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing the polyurea prepolymer, the mass volume ratio (g / mL) of toluene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate and tetrahydrofuran is 30-50:50-70:70-90.
7. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing the polyurea prepolymer, the isocyanate solution and the blocking agent solution react at 50-60° C. for 20-28 hours; the preheating condition for preparing the blocking agent solution is 40-50° C. for 30-50 minutes.
8. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing fiber-modified polyurea, the mass fraction ratio of aminated polyacrylonitrile fiber to polyurea prepolymer is 1-5:
100.
9. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: In the step of preparing the fiber-modified polyurea, in the auxiliary agent A, the mass volume ratio (g / mL) of 2-aminophenylboric acid, diethyltoluenediamine and tetrahydrofuran is 8-12:5-9:30-50.
10. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 9, characterized in that: In the step of preparing fiber-modified polyurea, the auxiliary agent A is added dropwise to the reaction mixture for 50-70 minutes at a reaction temperature of 40-60°C.
11. The method for preparing a polyurea material modified with polyacrylonitrile fiber according to claim 1, characterized in that: The step of preparing the fiber-modified polyurea also includes adding a catalyst, and the catalyst is dibutyltin dilaurate.
12. A fiber-modified polyurea product obtained by the method for preparing a polyacrylonitrile fiber-modified polyurea material according to any one of claims 1 to 11.
13. Use of a fiber-modified polyurea solution prepared by the method for preparing a polyacrylonitrile fiber-modified polyurea material according to any one of claims 1 to 11 in a transmission tower spraying material.
14. The use of the fiber-modified polyurea solution in a transmission tower spraying material according to claim 13, characterized in that: The fiber-modified polyurea solution is subjected to rotary evaporation to remove the solvent to a viscous state, and the viscous fiber-modified polyurea solution is inverted on a polytetrafluoroethylene mold and vacuum dried to obtain a transmission tower spray material.