Curing agent composition and preparation method thereof, epoxy composite material and preparation method thereof, and hard composite insulator

Abstract

The invention discloses a curing agent composition and a preparation method thereof, an epoxy composite material and a preparation method thereof, and a hard composite insulator. The curing agent composition comprises a first curing agent and a second curing agent, the first curing agent comprises an anhydride curing agent; the anhydride curing agent comprises one or more than two of tetrahydrophthalic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methyl hexahydrophthalic anhydride, chloridic anhydride, maleic anhydride and trimellitic anhydride glycerol; the second curing agent comprises one or two of o-toluene glycidyl ether and phenyl glycidyl ether. By introducing the curing agent composition with a rigid structure and a flexible chain segment, the heat resistance and toughness of the epoxy composite material are synergistically improved, the reliable epoxy composite material is provided for preparation of a hard composite insulator, and a safe and effective guarantee is provided for engineering of on-line monitoring of a power system.

Description

Technical Field

[0001] This invention relates to the field of power transmission line insulator technology, and more specifically, to a curing agent composition and its preparation method, an epoxy composite material and its preparation method, and a rigid composite insulator. Background Technology

[0002] With the rapid development of society and the economy, the demand for electricity from all sectors has increased significantly. As a type of power equipment, transmission lines require online monitoring to ensure their normal operation. Currently, the power supply for online monitoring equipment mainly utilizes rigid composite insulators with built-in coils. This not only solves insulation problems but also significantly improves energy transmission efficiency and reduces costs, showing great application potential and providing safe and reliable support for real-time status monitoring of transmission lines. Therefore, the mechanical properties and heat resistance of rigid composite insulator materials directly affect the operating status of power equipment.

[0003] As the current level increases, the temperature of the insulator rises, leading to aging of the rigid composite insulator. Under strong electric fields and concentrated stress, the rigid composite insulator may experience further damage such as partial discharge and surface discharge, resulting in breakdown and cracking of the rigid composite insulator material. This greatly affects the mechanical and heat resistance properties of the rigid composite insulator, thereby affecting its supporting and insulating protection function for transmission lines and becoming a major hidden danger to the reliable operation of the power system. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned defects in the prior art and provide a curing agent composition and its preparation method, and an epoxy composite material and its preparation method. 、 Rigid composite insulators achieve synergistic improvement in the heat resistance and toughness of epoxy composite materials by introducing a curing agent composition with rigid structure and flexible segments. This provides a reliable epoxy composite material for the preparation of rigid composite insulators and provides a safe and effective guarantee for the engineering of online monitoring of power systems.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A curing agent composition comprising a first curing agent and a second curing agent; the first curing agent comprising an acid anhydride curing agent; the acid anhydride curing agent comprising one or more of tetrahydrophthalic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, chlorine anhydride, maleic anhydride and trimellitic anhydride glycerol; the second curing agent comprising one or two of o-toluene glycidyl ether and phenyl glycidyl ether.

[0007] The present invention also discloses a method for preparing the curing agent composition as described above, comprising the following steps: mixing a first curing agent and a second curing agent to obtain the curing agent composition.

[0008] The present invention also discloses an epoxy composite material, the raw materials of which include the following components in weight percentage: 20% to 40% epoxy resin, 30% to 40% curing agent composition, 1% to 10% toughening agent, 10% to 50% filler, 1% to 10% accelerator, 0.5% to 5% flame retardant and 0.1% to 2% defoamer; wherein the curing agent composition is the above-mentioned curing agent composition.

[0009] This invention also discloses a method for preparing the epoxy composite material as described above, comprising the following steps:

[0010] Epoxy resin, curing agent composition, filler, flame retardant, toughening agent and defoamer are mixed to obtain epoxy resin mixture;

[0011] The epoxy resin mixture is mixed with an accelerator, and the epoxy resin mixture is cured to obtain the epoxy composite material.

[0012] The present invention also discloses a rigid composite insulator, comprising an epoxy composite material as described above or an epoxy composite material prepared by the preparation method described above.

[0013] Implementing the embodiments of the present invention will have the following beneficial effects:

[0014] This invention relates to a curing agent composition obtained by compounding a second curing agent with rigid groups and flexible segments with an acid anhydride curing agent. The second curing agent has epoxy groups. Under the action of an accelerator, the acid anhydride first undergoes a ring-opening reaction with the accelerator to generate carbium anions; the carbium anions react with the epoxy groups to generate alkoxy anions; the alkoxy anions react with the acid anhydride to generate carbium anions again, thus grafting them into the curing network of the epoxy composite to form a three-dimensional network epoxy composite system. Specifically, the epoxy composite system is comprehensively modified by rigid groups and flexible segments. The rigid groups in the acid anhydride curing agent and the second curing agent give the epoxy composite system a more stable cross-linked structure, effectively enhancing the heat resistance of the epoxy composite material. This avoids excessive density of rigid groups in the system, which reduces the migration ability of the composite molecular chain segments and decreases the toughness of the composite. The introduction of flexible segments introduces side chains with strong migration ability into the epoxy composite structure, increasing the migration ability of the cross-linked network structure under stress and promoting the improvement of the epoxy composite's toughness. Therefore, the curing agent composition with both rigid structure and flexible segments achieves synergistic improvement in the heat resistance and toughness of epoxy composite systems, providing reliable epoxy composite materials for the preparation of rigid composite insulators and providing a safe and effective guarantee for the engineering of online monitoring of power systems.

[0015] Meanwhile, the melting point of the curing agent composition obtained by mixing the acid anhydride curing agent and the second curing agent is lower than that of the acid anhydride curing agent and the second curing agent, respectively. This improves the processability of epoxy composites, simplifies the preparation process of epoxy composites, and enables the mass production of high-quality epoxy composites. Detailed Implementation

[0016] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] This invention discloses a curing agent composition, comprising a first curing agent and a second curing agent; the first curing agent comprises an acid anhydride curing agent; the acid anhydride curing agent comprises one or more of tetrahydrophthalic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, chlorogenic anhydride, maleic anhydride and trimellitic anhydride glycerol; the second curing agent comprises one or two of o-toluene glycidyl ether and phenyl glycidyl ether.

[0018] Specifically, in this embodiment of the invention, a curing agent composition is obtained by compounding a second curing agent with rigid groups and flexible -COC- segments with an anhydride curing agent. The second curing agent has epoxy groups. Under the action of an accelerator, the anhydride curing agent first undergoes a ring-opening reaction with the accelerator to generate carbium anions; the carbium anions react with the epoxy groups to generate alkoxy anions; the alkoxy anions react with the anhydride to generate carbium anions again, thus grafting them into the curing network of the epoxy composite to form a three-dimensional network epoxy composite system. The epoxy composite system is comprehensively modified by rigid groups and flexible -COC- segments. The rigid groups in the anhydride curing agent and the second curing agent give the epoxy composite system a more stable cross-linked structure, which can effectively enhance the heat resistance of the epoxy composite material. The introduction of flexible segments introduces side chains with strong migration ability into the epoxy composite structure, increasing the migration ability of the cross-linked network structure under stress and promoting the improvement of the toughness of the epoxy composite.

[0019] In one specific embodiment, the molar ratio of the first curing agent and the second curing agent is 1:(0.1~1).

[0020] The present invention also discloses a method for preparing a curing agent composition as described in any embodiment of the present invention, comprising the following steps: mixing a first curing agent and a second curing agent to obtain a curing agent composition.

[0021] Specifically, the curing agent composition obtained by mixing the acid anhydride curing agent and the second curing agent has a melting point lower than that of the acid anhydride curing agent and the second curing agent, which can improve the process performance of epoxy composites, simplify the preparation process of epoxy composites, and realize the mass production of high-quality epoxy composites.

[0022] In one specific embodiment, the mixing is carried out by stirring, with a stirring temperature of 80℃~120℃, a stirring time of 12h~36h, and a stirring speed of 300r / min~400r / min.

[0023] The present invention also discloses an epoxy composite material, the raw materials of which include the following components in weight percentage: 20% to 40% epoxy resin, 30% to 40% curing agent composition, 1% to 10% toughening agent, 10% to 50% filler, 1% to 10% accelerator, 0.5% to 5% flame retardant and 0.1% to 2% defoamer; the curing agent composition is the curing agent composition of any embodiment of the present invention.

[0024] In one specific embodiment, the filler is a first coupling agent modified filler. The first coupling agent modified filler can make the epoxy composite material denser and ensure the mechanical strength of the material.

[0025] In one specific embodiment, the first coupling agent modified filler comprises the following components by weight percentage: 50% to 70% of the first coupling agent and 30% to 50% of the inorganic filler.

[0026] In one specific embodiment, the first coupling agent includes one or more of γ-aminopropyltriethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane; the inorganic filler includes one or more of alumina, silicon oxide, microsilica, boron nitride, diamond, aluminum hydroxide, and aluminum nitride.

[0027] In one specific embodiment, the flame retardant is a second coupling agent modified flame retardant.

[0028] In one specific embodiment, the second coupling agent modified flame retardant comprises the following components in weight percentages: 50% to 70% of the second coupling agent and 30% to 50% of the flame retardant.

[0029] In one specific embodiment, the second coupling agent includes one or more of γ-aminopropyltriethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane; the flame retardant includes one or two of antimony trioxide and aluminum hydroxide.

[0030] In one specific embodiment, the epoxy resin includes one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD ​​type epoxy resin, diglycidyl phthalate, and diglycidyl isophthalate.

[0031] In one specific embodiment, the toughening agent includes one or more of polypropylene glycol, polypropylene glycol diglycidyl ether, polysulfide rubber, linoleic acid dimer diglycidyl ether, hydroxyl-terminated polyester, and carboxyl-terminated butadiene-acrylonitrile rubber. The toughening agent can improve the flexibility and elongation at break of the material.

[0032] In one specific embodiment, the accelerator includes one or more of 2-ethyl-4-methylimidazolium, N,N-dimethylbenzylamine, and 2,4,6-tris(dimethylaminomethyl)phenol.

[0033] In one specific embodiment, the defoamer includes one or more of fatty acid ester defoamers, oil ester defoamers, polyether defoamers, and polysiloxane defoamers.

[0034] The present invention also discloses a method for preparing an epoxy composite material as described in any embodiment of the present invention, comprising the following steps:

[0035] 1) Mix epoxy resin, curing agent composition, filler, flame retardant, toughening agent and defoamer to obtain epoxy resin mixture;

[0036] In one specific embodiment, step 1) specifically includes the following steps:

[0037] 1.1) Place the epoxy resin, curing agent composition, filler, flame retardant, toughening agent, defoamer and accelerator in a vacuum drying oven at a temperature of 60℃~120℃ for vacuum drying treatment for 3h~8h to remove moisture and gas impurities from the material.

[0038] 1.2) Weigh the dried epoxy resin, toughening agent and defoamer according to the proportions of any embodiment of the present invention, and stir them in a reaction vessel at 60℃~200℃ for 20min~200min, with a stirring speed of 300r / min~400r / min.

[0039] 1.3) The dried curing agent composition, modified filler and modified flame retardant are mixed with the mixed solution obtained in step 1.2) under vacuum stirring at 40℃~80℃ for 10min~20min, and the stirring speed is 300r / min~400r / min.

[0040] 2) Mix the epoxy resin mixture with an accelerator and cure the epoxy resin mixture to obtain an epoxy composite material.

[0041] In one specific embodiment, the curing temperature in step 2) is 80℃~140℃, and the curing time is 6h~12h.

[0042] In one specific embodiment, the preparation method of the first coupling agent modified filler includes the following steps: mixing the filler and the first coupling agent with an inorganic solution, and heating and stirring the mixture thoroughly in a reaction vessel at 20°C to 50°C for 70 min to 120 min, with a stirring speed of 300 r / min to 400 r / min.

[0043] In one specific embodiment, the preparation method of the second coupling agent modified flame retardant includes the following steps: mixing the flame retardant and the second coupling agent with an inorganic solution, and heating and stirring the mixture thoroughly in a reaction vessel at 20°C to 50°C for 70 min to 120 min, with a stirring speed of 300 r / min to 400 r / min.

[0044] The present invention also discloses a rigid composite insulator, comprising an epoxy composite material as described in any embodiment of the present invention or an epoxy composite material prepared by the preparation method described in any embodiment of the present invention.

[0045] Specifically, the epoxy composite material provided by this invention, through the rational selection of the types and proportions of epoxy resin, curing agent composition and additives, enables the cured material to have excellent heat resistance, toughness and rigidity, providing a reliable epoxy composite material for the preparation of rigid composite insulators and providing a safe and effective guarantee for the engineering of online monitoring of power systems.

[0046] The following are specific embodiments.

[0047] Example 1

[0048] The epoxy composite material of this embodiment comprises the following components by weight percentage: 10% diglycidyl phthalate, 20% bisphenol A type epoxy resin, 35% curing agent composition, 5% polypropylene glycol, 25% first coupling agent modified filler, 2% 2-ethyl-4-methylimidazolium, 2% second coupling agent modified flame retardant, and 1% polysiloxane defoamer.

[0049] The curing agent composition comprises phthalic anhydride, hexahydrophthalic anhydride, and o-toluene glycidyl ether in a molar ratio of 1.5:7:1.5.

[0050] The preparation method of the epoxy composite material in this embodiment includes the following steps:

[0051] 1.1) Phthalic anhydride, hexahydrophthalic anhydride and o-toluene glycidyl ether were stirred at 80°C for 24 h at a stirring speed of 350 r / min to obtain a curing agent composition.

[0052] 1.2) Mix 60% of the first coupling agent, 30% of silica and 10% of aluminum hydroxide with DMSO and heat and stir thoroughly in a reaction vessel at 50°C for 100 min at a stirring speed of 350 r / min to obtain the first coupling agent modified filler.

[0053] 1.3) Mix 60% of the second coupling agent and 40% of antimony trioxide with DMSO and heat and stir thoroughly in a reaction vessel at 50°C for 100 min at a stirring speed of 350 r / min to obtain the second coupling agent modified flame retardant.

[0054] 1.4) Diglycidyl phthalate, bisphenol A epoxy resin, curing agent composition, first coupling agent modified filler, second coupling agent modified flame retardant, polypropylene glycol, polysiloxane defoamer and 2-ethyl-4-methylimidazole were placed in a vacuum drying oven at 70°C and vacuum dried for 5 hours.

[0055] 1.5) Weigh the dried epoxy resin, polypropylene glycol and polysiloxane defoamer according to the proportions in this embodiment, and stir them in a reaction vessel at 60°C for 20 minutes at a stirring speed of 300 r / min.

[0056] 1.6) The dried curing agent composition, the first coupling agent modified filler and the second coupling agent modified flame retardant are mixed with the mixed solution obtained in step 1.5) under vacuum stirring at 80°C for 20 min at a stirring speed of 350 r / min.

[0057] 1.7) The epoxy resin mixture obtained in step 1.6) is mixed with 2-ethyl-4-methylimidazole at 140°C for 10 h to cure the epoxy resin mixture and obtain an epoxy composite material.

[0058] Example 2

[0059] The epoxy composite material of this embodiment comprises the following components by weight percentage: 35% diglycidyl isophthalate, 38% curing agent composition, 5% carboxyl-terminated nitrile butadiene rubber, 17% first coupling agent modified filler, 2% N,N-dimethylbenzylamine, 2% second coupling agent modified flame retardant and 1% polyether defoamer.

[0060] The curing agent composition comprises tetrahydrophthalic anhydride and phenyl glycidyl ether in a molar ratio of 1:0.2.

[0061] The preparation method of this embodiment is the same as that of Example 1. The epoxy composite material of this embodiment is prepared according to the preparation method of steps 1.1) to 1.7) in Example 1.

[0062] Example 3

[0063] The epoxy composite material of this embodiment comprises the following components by weight percentage: 40% bisphenol F type epoxy resin, 33% curing agent composition, 8% linoleic acid dimer diglycidyl ether, 15% first coupling agent modified filler, 2% 2,4,6-tris(dimethylaminomethyl)phenol, 1% second coupling agent modified flame retardant and 1% fatty acid ester defoamer.

[0064] The curing agent composition comprises chlorine anhydride, maleic anhydride, and o-toluene glycidyl ether in a molar ratio of 2.5:6:1.5.

[0065] The preparation method of this embodiment is the same as that of Example 1. The epoxy composite material of this embodiment is prepared according to the preparation method of steps 1.1) to 1.7) in Example 1.

[0066] Comparative Example 1

[0067] The only difference between this comparative example and Example 1 is that this comparative example does not contain a second curing agent. The epoxy composite material of this comparative example comprises the following components by weight percentage: 10% diglycidyl phthalate, 20% bisphenol A type epoxy resin, 35% first curing agent, 5% polypropylene glycol, 25% first coupling agent modified filler, 2% 2-ethyl-4-methylimidazolium, 2% second coupling agent modified flame retardant, and 1% polysiloxane defoamer. The first curing agent comprises phthalic anhydride and hexahydrophthalic anhydride in a molar ratio of 3:14.

[0068] Comparative Example 2

[0069] The only difference between this comparative example and Example 2 is that this comparative example does not contain a second curing agent. The epoxy composite material of this comparative example includes the following components by weight percentage: 30% diglycidyl isophthalate, 35% tetrahydrophthalic anhydride, 5% carboxyl-terminated nitrile butadiene rubber, 25% first coupling agent modified filler, 2% N,N-dimethylbenzylamine, 2% second coupling agent modified flame retardant, and 1% polyether defoamer.

[0070] Comparative Example 3

[0071] The only difference between this comparative example and Example 3 is that this comparative example does not contain a second curing agent. The epoxy composite material of this comparative example comprises the following components by weight percentage: 32% bisphenol F type epoxy resin, 33% first curing agent, 5% linoleic acid dimer diglycidyl ether, 25% modified filler, 2% 2,4,6-tris(dimethylaminomethyl)phenol, 2% modified flame retardant, and 1% fatty acid ester defoamer. The first curing agent comprises maleic anhydride and chlorogenic anhydride in a molar ratio of 5:12.

[0072] Test case

[0073] 1. Process performance tests were conducted on Examples 1-3 and Comparative Examples 1-3. During the curing process of the epoxy composite material, its initial viscosity and gel time were tested, and the test results are shown in Table 1.

[0074] Table 1 Processing properties of epoxy composite materials

[0075] Initial viscosity (mPa·s) Gel time (min) Example 1 25 72 Example 2 33 82 Example 3 30 69 Comparative Example 1 37 52 Comparative Example 2 55 15 Comparative Example 3 48 43

[0076] The test results show that Comparative Examples 1-3 have higher initial viscosities and shorter gel times compared to Examples 1-3. This is because the melting point of the anhydride curing agent in Comparative Examples 1-3 is higher than that of the curing agent composition formed by the anhydride curing agent and the second curing agent in Examples 1-3. Therefore, the curing agent in Comparative Examples 1-3 reacts with the epoxy resin faster, reducing the use window time of the epoxy resin mixture and decreasing its processability.

[0077] 2. Mechanical properties were tested on Examples 1-3 and Comparative Examples 1-3, including their bending strength and impact strength. The test results are shown in Table 2.

[0078] Table 2 Mechanical properties of epoxy composites

[0079] Bending strength (MPa) Impact strength (KJ / m2) Example 1 72 25 Example 2 68 22 Example 3 68 19 Comparative Example 1 62 17 Comparative Example 2 38 5 Comparative Example 3 55 12

[0080] The test results show that Comparative Examples 1-3 exhibited lower flexural and impact strength compared to Examples 1-3. This is because the epoxy composite system was comprehensively modified using rigid groups and flexible COC segments. The rigid groups in the anhydride curing agent and the second curing agent resulted in a more stable cross-linked structure for the epoxy composite system, while the flexible segments introduced side chains with strong migration capabilities into the epoxy composite structure. This increased the migration ability of the cross-linked network structure under stress, thus promoting the improvement of the epoxy composite's toughness.

[0081] 3. Thermogravimetric analysis and dynamic thermomechanical analysis were performed on Examples 1-3 and Comparative Examples 1-3 to test their thermal decomposition temperature (T5%), maximum thermal degradation rate temperature (Tmax), and glass transition temperature (Tg). The test results are shown in Table 3.

[0082] Table 3. Heat resistance properties of epoxy composite materials

[0083] T5％(℃) Tmax (°C) Tg (°C) Example 1 351 421 142.85 Example 2 356 431 146.82 Example 3 361 432 144.21 Comparative Example 1 339 409 135.62 Comparative Example 2 355 430 145.79 Comparative Example 3 348 419 139.85

[0084] The test results show that the heat resistance of Examples 1-3 is better than that of Comparative Examples 1-3. By introducing a second curing agent with rigid groups on the basis of anhydride curing agent, the epoxy composite system has a more stable cross-linking structure, which can effectively enhance the heat resistance of epoxy composite materials.

[0085] In summary, the epoxy composite material provided by this invention, by introducing a curing agent composition with rigid structure and flexible segments, enables the cured material to have excellent heat resistance, toughness and rigidity, while improving the processability of the composite material. This provides a reliable epoxy composite material for the preparation of rigid composite insulators and provides a safe and effective guarantee for the engineering of online monitoring of power systems.

[0086] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A curing agent composition, characterized in that, Includes a first curing agent and a second curing agent; The first curing agent includes an acid anhydride curing agent; the acid anhydride curing agent includes one or more of tetrahydrophthalic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, chlorine anhydride, maleic anhydride and trimellitic anhydride glycerol; The second curing agent includes one or both of o-toluene glycidyl ether and phenyl glycidyl ether.

2. The curing agent composition according to claim 1, characterized in that, The molar ratio of the first curing agent to the second curing agent is 1:(0.1~1).

3. A method for preparing a curing agent composition according to any one of claims 1 to 2, characterized in that, Includes the following steps: The first curing agent and the second curing agent are mixed to obtain the curing agent composition.

4. An epoxy composite material, characterized in that, Its raw materials include the following components by weight percentage: 20%–40% epoxy resin, 30%–40% curing agent composition, 1%–10% toughening agent, 10%–50% filler, 1%–10% accelerator, 0.5%–5% flame retardant and 0.1%–2% defoamer; The curing agent composition is the curing agent composition according to any one of claims 1 to 2.

5. The epoxy composite material according to claim 4, characterized in that, The filler is a first coupling agent modified filler; The flame retardant is a second coupling agent modified flame retardant.

6. The epoxy composite material according to claim 5, characterized in that, The first coupling agent modified filler comprises the following components by weight percentage: 50% to 70% of the first coupling agent and 30% to 50% of the inorganic filler; The second coupling agent modified flame retardant comprises the following components by weight percentage: 50% to 70% of the second coupling agent and 30% to 50% of the flame retardant.

7. The epoxy composite material according to claim 6, characterized in that, The first coupling agent and the second coupling agent respectively comprise one or both of γ-aminopropyltriethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane; The inorganic filler includes one or more of alumina, silicon oxide, microsilica powder, boron nitride, diamond, aluminum hydroxide, and aluminum nitride. The flame retardant includes one or both of antimony trioxide and aluminum hydroxide.

8. The epoxy composite material according to claim 4, characterized in that, The epoxy resin includes one or more of bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD ​​type epoxy resin, diglycidyl phthalate and diglycidyl isophthalate. The toughening agent includes one or more of the following: polypropylene glycol, polypropylene glycol diglycidyl ether, polysulfide rubber, linoleic acid dimer diglycidyl ether, hydroxyl-terminated polyester, and carboxyl-terminated butadiene nitrile rubber. The accelerator includes one or more of 2-ethyl-4-methylimidazolium, N,N-dimethylbenzylamine, and 2,4,6-tris(dimethylaminomethyl)phenol; The defoamer includes one or more of fatty acid ester defoamers, oil ester defoamers, polyether defoamers, and polysiloxane defoamers.

9. A method for preparing an epoxy composite material as described in any one of claims 5 to 8, characterized in that, Includes the following steps: Epoxy resin, curing agent composition, filler, flame retardant, toughening agent and defoamer are mixed to obtain epoxy resin mixture; The epoxy resin mixture is mixed with an accelerator, and the epoxy resin mixture is cured to obtain the epoxy composite material.

10. A rigid composite insulator, characterized in that, This includes the epoxy composite material as described in any one of claims 5 to 8 or the epoxy composite material prepared by the preparation method described in claim 9.