A high-performance resin material for transformer insulation cylinders and its preparation method

Abstract

This invention relates to a high-performance resin material for transformer insulation cylinders. The high-performance resin material for transformer insulation cylinders of this invention is a compound of organosilicon-modified epoxy resin, modified silicon carbide, and modified spherical alumina. The modified silicon carbide, modified spherical alumina, and organosilicon-modified epoxy resin exhibit excellent compatibility and stability, effectively improving the interfacial compatibility between the filler and the organosilicon-modified epoxy resin, enhancing interfacial bonding, reducing system viscosity, and significantly improving the mechanical properties of the resin material. Furthermore, due to the low-polarity siloxane structure of the POSS group, its molecules contain numerous nanoscale cavities, which can effectively reduce the dielectric constant and dielectric loss of the resin.

Description

Technical Field

[0001] This invention relates to the field of electrical equipment insulation materials, and in particular to a high-performance resin material for transformer insulation cylinders and its preparation method. Background Technology

[0002] In the field of power equipment, transformer insulation cylinders are critical insulating components inside transformers, and their performance directly affects the safety and service life of the transformer. Therefore, extremely stringent requirements are placed on the electrical insulation, mechanical strength, thermal conductivity, and long-term thermal stability of the materials used. The resin materials for transformer insulation cylinders need to achieve a balance across multiple dimensions, including electrical performance, mechanical performance, thermal performance, and environmental tolerance, while also considering processability and environmental friendliness.

[0003] However, existing resins used in transformer insulation cylinders suffer from numerous technical problems in practical applications: 1. Traditional resins have insufficient high-temperature resistance, making them prone to aging and cracking during long-term operation; 2. They are prone to generating bubbles or internal stress during curing, leading to a decrease in the mechanical strength of the insulation cylinder; 3. They have poor environmental friendliness (e.g., containing volatile solvents); 4. Their dielectric properties or resistance to partial discharge are insufficient; 5. Their processing performance is limited, resulting in poor flowability; 6. The interfacial compatibility between the thermally conductive filler and the resin matrix is ​​poor. This causes the filler to be unevenly dispersed in the matrix and prone to agglomeration, which not only affects the mechanical properties of the insulation cylinder but also reduces its thermal conductivity.

[0004] Therefore, there is an urgent need to develop a high-performance resin material that can significantly improve thermal conductivity and thermal stability while ensuring excellent electrical insulation and mechanical properties, in order to meet the growing demand for insulation cylinder materials in modern high-performance transformers. Summary of the Invention

[0005] Therefore, it is necessary to provide a high-performance resin material for transformer insulation cylinders, the raw materials comprising the following components in parts by weight:

[0006]

[0007] The modified silicon carbide is obtained by reacting hydroxylated silicon carbide with epoxy group POSS.

[0008] The modified spherical alumina is obtained by reacting hydroxylated spherical alumina with epoxy group POSS.

[0009] Furthermore, the curing agent is selected from one or more of polyetheramine curing agents, aliphatic amine curing agents, tertiary amine curing agents, and latent curing agents.

[0010] Furthermore, the photoinitiator is selected from one or more of TPO, diaryliodonium salt, and triaryliodonium salt.

[0011] Furthermore, the silicon carbide has a particle size of 1-5 μm.

[0012] Furthermore, the particle size of the spherical alumina is 5-10 μm.

[0013] This invention also provides a method for preparing the high-performance resin material for transformer insulating cylinders, comprising the following steps:

[0014] S1. Octadecyl cage-like silsesquioxane, acetic acid, and concentrated sulfuric acid are added to a solvent, followed by hydrogen peroxide. The mixture is heated to react and yield epoxy group POSS.

[0015] S2. Hydroxylated silicon carbide and epoxy-based POSS are added to a solvent and heated to react, thereby obtaining modified silicon carbide.

[0016] S3. Hydroxylated spherical alumina and epoxy group POSS are added to a solvent and heated to react, thereby obtaining modified spherical alumina.

[0017] Furthermore, in step S1, the temperature of the heating reaction is 60-65°C.

[0018] Furthermore, in step S2, the heating temperature is 35-55°C.

[0019] Furthermore, in step S3, the heating temperature is 35-45°C.

[0020] The present invention also provides the application of the high-performance resin material for transformer insulating cylinders in electrical equipment insulating materials.

[0021] The present invention has the following beneficial effects:

[0022] The high-performance resin material for transformer insulation cylinders of the present invention is a compound of organosilicon-modified epoxy resin, modified silicon carbide, and modified spherical alumina. First, under the action of concentrated sulfuric acid and hydrogen peroxide, the vinyl group of the upper part of octavinyl cage-like silsesquioxane reacts with acetic acid to obtain epoxy-based POSS containing vinyl and epoxy groups. Then, silicon carbide and spherical alumina are hydroxylated to obtain hydroxylated silicon carbide and hydroxylated spherical alumina, respectively. Finally, the epoxy groups of epoxy-based POSS react with hydroxylated silicon carbide and hydroxylated spherical alumina, respectively, to introduce epoxy-based POSS groups onto the modified silicon carbide and modified spherical alumina, respectively.

[0023] On the one hand, the POSS group segments introduced onto modified silicon carbide and modified spherical alumina have similar polarity to organosilicon-modified epoxy resin, giving the modified silicon carbide, modified spherical alumina and organosilicon-modified epoxy resin and other components excellent compatibility and stability. This can not only effectively improve the interfacial compatibility between fillers and organosilicon-modified epoxy resin, enhance interfacial bonding force, and reduce system viscosity, but also further improve the mechanical properties of resin materials based on the toughening effect of POSS itself. Furthermore, since the POSS group is a low-polarity siloxane structure, there are a large number of nanoscale cavities inside its molecules, which can effectively reduce the dielectric constant and dielectric loss of the resin.

[0024] On the other hand, modified silicon carbide and modified spherical alumina can react under the action of photoinitiator and curing agent during subsequent curing to form a network cross-linked structure, which effectively fixes the modified silicon carbide and modified spherical alumina, inhibits their agglomeration, and facilitates the uniform dispersion of modified silicon carbide and modified spherical alumina in the resin material, exerting a synergistic effect, improving the thermal conductive network structure, giving the product good fluidity and permeability, achieving gapless filling, and improving mechanical strength and resistance to partial discharge. Detailed Implementation

[0025] To more clearly illustrate the technical solution of the present invention, the following embodiments are provided. Unless otherwise stated, the raw materials, reactions, and post-processing methods appearing in the embodiments are all commercially available raw materials and technical methods well known to those skilled in the art.

[0026] The terms "preferred," "more preferably," and "more suitable" used in this invention refer to embodiments of the invention that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this invention.

[0027] It should be understood that, except in any operational instance or otherwise indicated, all figures representing the amounts of ingredients used, for example, in the specification and claims, should be understood to be modified in all cases by the term "about". Therefore, unless otherwise stated, the numerical parameters set forth in the following specification and appended claims are approximations varying with the desired performance to be obtained according to the invention.

[0028] Silicone-modified epoxy resin, Shin-Etsu silicone-modified epoxy resin ES-1001N.

[0029] Curing agent, Ajinomoto curing agent PN-40 latent epoxy curing agent.

[0030] Photoinitiator, TPO, 2,4,6-(trimethylbenzoyl)diphenylphosphine oxide.

[0031] Octadecyl cage silsesquioxane, OV-POSS, purchased from Forsmann Technology (Beijing) Co., Ltd.

[0032] In the embodiments of this invention, "parts" refers to parts by mass.

[0033] Example 1

[0034] A high-performance resin material for transformer insulation cylinders, comprising the following components in parts by weight:

[0035]

[0036] The preparation method of the above-mentioned high-performance resin material for transformer insulation cylinders includes the following steps:

[0037] S1-1. Silicon carbide powder was soaked in a 2 mol / L hydrochloric acid solution, stirred at 75°C for 2 h, centrifuged, washed, and dried to obtain hydroxylated silicon carbide.

[0038] S1-2. Immerse spherical alumina in a 50wt% hydrogen peroxide solution, stir at 80℃ for 4h, filter and dry to obtain hydroxylated spherical alumina;

[0039] S1-3. Add 6 parts of octavinyl cage-like silsesquioxane, 25 parts of acetic acid, and 1 part of concentrated sulfuric acid to 120 parts of chloroform, heat to 60°C, then add 15 parts of hydrogen peroxide, heat to 65°C and reflux for 18 hours. Separate the layers, take the lower layer, wash, remove the solvent, and obtain epoxy group POSS.

[0040] S2. Add 3 parts of hydroxylated silicon carbide, 1.5 parts of epoxy POSS, and 1 part of 30 wt% sodium hydroxide solution to 20 parts of tetrahydrofuran, heat to 45°C and react for 6 hours. After the reaction is completed, add 1 part of HCl, distill to remove the solvent, add deionized water, filter, and dry to obtain modified silicon carbide.

[0041] S3. Add 3 parts of hydroxylated spherical alumina, 1.5 parts of epoxy POSS, and 1 part of 30 wt% sodium hydroxide solution to 20 parts of tetrahydrofuran, heat to 45°C and react for 6 hours. After the reaction is completed, add 1 part of HCl, distill to remove the solvent, add deionized water, filter, and dry to obtain modified spherical alumina.

[0042] S4-1. According to the above mass proportions, the modified spherical alumina, modified silicon carbide and the remaining components are blended and planetarily stirred in a vacuum environment of -0.095MPa to obtain a high-performance resin material for transformer insulation cylinder.

[0043] S4-2. Inject the high-performance resin material for transformer insulation cylinders into the mold, under a light intensity of 30mW / cm². 2 Irradiate the material under a 365nm light source for 100 seconds, then heat it to 80℃ for 1 hour, then heat it to 130℃ for 1 hour, and finally heat it to 150℃ for 0.5 hours. Remove the mold and obtain the cured high-performance resin material for testing.

[0044] Example 2

[0045] A high-performance resin material for transformer insulation cylinders, comprising the following components in parts by weight:

[0046]

[0047] The preparation method of the above-mentioned high-performance resin material for transformer insulation cylinders includes the following steps:

[0048] S1-1. Silicon carbide powder was soaked in a 2 mol / L hydrochloric acid solution, stirred at 75°C for 2 h, centrifuged, washed, and dried to obtain hydroxylated silicon carbide.

[0049] S1-2. Immerse spherical alumina in a 50wt% hydrogen peroxide solution, stir at 80℃ for 4h, filter and dry to obtain hydroxylated spherical alumina;

[0050] S1-3. Add 6 parts of octavinyl cage-like silsesquioxane, 25 parts of acetic acid, and 1 part of concentrated sulfuric acid to 120 parts of chloroform, heat to 60°C, then add 15 parts of hydrogen peroxide, heat to 65°C and reflux for 18 hours. Separate the layers, take the lower layer, wash, remove the solvent, and obtain epoxy group POSS.

[0051] S2. Add 3 parts of hydroxylated silicon carbide, 1.5 parts of epoxy POSS, and 1 part of 30 wt% sodium hydroxide solution to 20 parts of tetrahydrofuran, heat to 45°C and react for 6 hours. After the reaction is completed, add 1 part of HCl, distill to remove the solvent, add deionized water, filter, and dry to obtain modified silicon carbide.

[0052] S3. Add 3 parts of hydroxylated spherical alumina, 1.5 parts of epoxy POSS, and 1 part of 30 wt% sodium hydroxide solution to 20 parts of tetrahydrofuran, heat to 45°C and react for 6 hours. After the reaction is completed, add 1 part of HCl, distill to remove the solvent, add deionized water, filter, and dry to obtain modified spherical alumina.

[0053] S4-1. According to the above mass proportions, the modified spherical alumina, modified silicon carbide and the remaining components are blended and planetarily stirred in a vacuum environment of -0.095MPa to obtain a high-performance resin material for transformer insulation cylinder.

[0054] S4-2. Inject the high-performance resin material for transformer insulation cylinders into the mold, under a light intensity of 30mW / cm². 2 Irradiate the material under a 365nm light source for 100 seconds, then heat it to 80℃ for 1 hour, then heat it to 130℃ for 1 hour, and finally heat it to 150℃ for 0.5 hours. Remove the mold and obtain the cured high-performance resin material for testing.

[0055] Example 3

[0056] A high-performance resin material for transformer insulation cylinders, comprising the following components in parts by weight:

[0057]

[0058] The preparation method of the above-mentioned high-performance resin material for transformer insulation cylinders includes the following steps:

[0059] S1-1. Silicon carbide powder was soaked in a 2 mol / L hydrochloric acid solution, stirred at 75°C for 2 h, centrifuged, washed, and dried to obtain hydroxylated silicon carbide.

[0060] S1-2. Immerse spherical alumina in a 50wt% hydrogen peroxide solution, stir at 80℃ for 4h, filter and dry to obtain hydroxylated spherical alumina;

[0061] S1-3. Add 6 parts of octavinyl cage-like silsesquioxane, 25 parts of acetic acid, and 1 part of concentrated sulfuric acid to 120 parts of chloroform, heat to 60°C, then add 15 parts of hydrogen peroxide, heat to 65°C and reflux for 18 hours. Separate the layers, take the lower layer, wash, remove the solvent, and obtain epoxy group POSS.

[0062] S2. Add 3 parts of hydroxylated silicon carbide, 1.5 parts of epoxy POSS, and 1 part of 30 wt% sodium hydroxide solution to 20 parts of tetrahydrofuran, heat to 45°C and react for 6 hours. After the reaction is completed, add 1 part of HCl, distill to remove the solvent, add deionized water, filter, and dry to obtain modified silicon carbide.

[0063] S3. Add 3 parts of hydroxylated spherical alumina, 1.5 parts of epoxy POSS, and 1 part of 30 wt% sodium hydroxide solution to 20 parts of tetrahydrofuran, heat to 45°C and react for 6 hours. After the reaction is completed, add 1 part of HCl, distill to remove the solvent, add deionized water, filter, and dry to obtain modified spherical alumina.

[0064] S4-1. According to the above mass proportions, the modified spherical alumina, modified silicon carbide and the remaining components are blended and planetarily stirred in a vacuum environment of -0.095MPa to obtain a high-performance resin material for transformer insulation cylinder.

[0065] S4-2. Inject the high-performance resin material for transformer insulation cylinders into the mold, under a light intensity of 30mW / cm². 2 Irradiate the material under a 365nm light source for 100 seconds, then heat it to 80℃ for 1 hour, then heat it to 130℃ for 1 hour, and finally heat it to 150℃ for 0.5 hours. Remove the mold and obtain the cured high-performance resin material for testing.

[0066] Comparative Example 1

[0067] A resin material, the difference between this comparative example and Example 1 is that: steps S1-1 and S2 are removed, and KH560 modified silicon carbide is used to replace the modified silicon carbide by mass, while other components and preparation methods are the same.

[0068] The preparation method of the KH560 modified silicon carbide includes the following steps:

[0069] Using ethanol as a solvent, 30 parts of spherical silicon carbide, 1.5 parts of KH560 silane coupling agent, and 5 parts of deionized water were mixed and heated to 60°C for 12 hours. The mixture was then filtered and washed to obtain the product.

[0070] Comparative Example 2

[0071] A resin material, the difference between this comparative example and Example 1 is that: steps S1-2 and step S3 are removed, and KH560 modified spherical alumina is used to replace the modified spherical alumina by the same mass, while other components and preparation methods are the same.

[0072] The method for preparing KH560 modified spherical alumina includes the following steps:

[0073] Using ethanol as a solvent, 30 parts of spherical alumina, 1.5 parts of KH560 silane coupling agent, and 5 parts of deionized water were mixed and heated to 70°C for 2.5 hours. The mixture was then filtered and washed to obtain the product.

[0074] Comparative Example 3

[0075] An epoxy resin, SM128, was purchased from Jiangsu Sanmu Chemical Co., Ltd.

[0076] Test Example 1

[0077] The performance of the resin materials prepared in Example 1 and Comparative Examples 1-3 was tested.

[0078] Insulation resistance test: The test shall be conducted in accordance with Chapter 6.2 of Part 2 of GB / T 5132.2-2009.

[0079] Dielectric strength test: Tested according to GB / T 1408.1-2016 Fast voltage boost.

[0080] Dielectric loss factor test: The test shall be conducted in accordance with Chapter 6.3 of Part 2 of GB / T 5132.2-2009.

[0081] Vertical layer bending strength test: The test shall be conducted in accordance with Chapter 5.1 of Part 2 of GB / T 5132.2.

[0082] Water absorption test: The test shall be conducted in accordance with GB / T 1034-2008 (Method 1).

[0083] Partial discharge quantity test: The test shall be conducted in accordance with Chapter 4 of GB / T 7354-2018.

[0084] The test results are shown in Table 1.

[0085] Table 1. Performance test results of the resin materials in Examples 1 and Comparative Examples 1-3

[0086]

[0087]

[0088] According to Table 1, the performance of the resin material using the present invention is significantly better than that of the resin materials in Comparative Examples 1-3.

[0089] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0090] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-performance resin material for transformer insulating cylinders, characterized in that, The raw materials consist of the following components in parts by weight: 80-100 parts of silicone-modified epoxy resin 8-12 parts of modified silicon carbide 35-40 parts of modified spherical alumina 5-7 parts of curing agent 1-3 parts of photoinitiator; The modified silicon carbide is obtained by reacting hydroxylated silicon carbide with epoxy group POSS. The modified spherical alumina is obtained by reacting hydroxylated spherical alumina with epoxy group POSS; The preparation method of the epoxy-based POSS includes the following steps: Octadecrylidene cage silsesquioxane, acetic acid, and concentrated sulfuric acid were added to a solvent, followed by hydrogen peroxide. The mixture was then heated to react and yield epoxy group POSS.

2. The high-performance resin material for transformer insulating cylinders according to claim 1, characterized in that, The curing agent is selected from one or more of polyetheramine curing agents, aliphatic amine curing agents, tertiary amine curing agents, and latent curing agents.

3. The high-performance resin material for transformer insulating cylinders according to claim 1, characterized in that, The photoinitiator is selected from one or more of TPO, diaryliodonium salt, and triaryliodonium salt.

4. The high-performance resin material for transformer insulating cylinders according to claim 1, characterized in that, The silicon carbide has a particle size of 1-5 μm.

5. The high-performance resin material for transformer insulating cylinders according to claim 4, characterized in that, The spherical alumina has a particle size of 5-10 μm.

6. The method for preparing the high-performance resin material for transformer insulating cylinders according to any one of claims 1-5, characterized in that, Includes the following steps: S1. Octadecyl cage-like silsesquioxane, acetic acid, and concentrated sulfuric acid are added to a solvent, followed by hydrogen peroxide. The mixture is heated to react and yield epoxy group POSS. S2. Hydroxylated silicon carbide and epoxy-based POSS are added to a solvent and heated to react, thereby obtaining modified silicon carbide. S3. Hydroxylated spherical alumina and epoxy group POSS are added to a solvent and heated to react, thereby obtaining modified spherical alumina.

7. The method for preparing the high-performance resin material for transformer insulating cylinders according to claim 6, characterized in that, In step S1, the temperature of the heating reaction is 60-65℃.

8. The method for preparing the high-performance resin material for transformer insulating cylinders according to claim 7, characterized in that, In step S2, the heating temperature is 35-55℃.

9. The method for preparing the high-performance resin material for transformer insulating cylinders according to claim 7, characterized in that, In step S3, the heating temperature is 35-45℃.

10. The application of the high-performance resin material for transformer insulating cylinders as described in any one of claims 1-5 in electrical equipment insulating materials.

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