Dual active epoxy resin curing agent, epoxy resin composition and application thereof

Abstract

The application discloses a dual-activity epoxy resin curing agent, an epoxy resin composition and application thereof. The epoxy resin composition has the capabilities of low-temperature rapid thickening, room-temperature storage stability, high-temperature rapid curing, and the cured product has relatively high mechanical and heat-resistant properties, and can be prepared into an epoxy resin composite material with good temperature-resistant performance through various composite material forming processes, especially SMC, prepreg and other forming process application fields.

Description

Technical Field

[0001] This invention belongs to the field of SMC molding application of epoxy resin composite materials, specifically relating to an epoxy resin curing agent with dual activity and an epoxy resin composition, which has the performance characteristics of low-temperature thickening, stable storage, and high-temperature rapid curing. Background Technology

[0002] Currently, the market for preparing resin-based composite materials using SMC mainly falls into two categories: unsaturated resins and epoxy / latent curing agent systems. Unsaturated resins often suffer from problems such as strong odor, environmental pollution, and high product shrinkage. The current trend is towards more environmentally friendly epoxy systems. Epoxy resin systems are most commonly paired with dicyandiamide-based latent curing agents, which, while providing a long shelf life, require more stringent conditions in the initial thickening and post-curing processes due to the low reactivity of these curing agents, increasing energy consumption and reducing production efficiency. However, by introducing curing agents with dual reactivity, epoxy resin systems achieve the goals of rapid initial thickening, stable storage in the middle stage, and low-temperature curing in the later stage, thus achieving low energy consumption and high efficiency.

[0003] Chinese patent CN114907673A discloses an epoxy SMC composite material and its preparation method. It uses dicyandiamide as a curing agent and introduces organic urea as an accelerator to efficiently prepare epoxy-based SMC sheets. However, it still has a medium-temperature heating stage for early thickening and the later curing temperature still reaches above 150℃, which places high demands on the production process and energy consumption, and has certain limitations in practical applications.

[0004] Chinese patent CN114057954A uses unsaturated polyester resin as the main raw material and introduces polyethersulfone to significantly increase the toughness of SMC materials, improving their impact strength and elongation at break. However, the system contains a large amount of volatile monomers such as styrene. On the one hand, the resin system has a high curing shrinkage rate, which is not conducive to the dimensional stability of the product. On the other hand, styrene itself is highly volatile and has a strong odor, which has a significant impact on the environment and is not in line with the current trend of environmental protection.

[0005] Chinese patent CN101654504B uses 4-((4-aminocyclohexane)methane)aniline as the main raw material. Through alkylation modification of the terminal amino group, it can significantly extend the working life and improve the flexibility of the cured resin. However, its active hydrogen is replaced, the functionality of the compound is reduced, and the crosslinking density as an epoxy resin curing agent is reduced. Its application feasibility in composite materials needs to be verified, including mechanical properties, heat resistance, etc.

[0006] To address the aforementioned problems, this invention develops a dual-active epoxy resin / curing agent composition and its applications. Utilizing the structural characteristics of the novel curing agent 4-(4-aminobenzyl)cyclohexylurea, which simultaneously possesses alicyclic urea (active group) and aromatic amine (inert group), it can achieve room temperature thickening to reach the curing stage (B stage), and has a long shelf life (≥45 days). It can also achieve rapid curing under medium to high temperature conditions, exhibiting high mechanical strength and high Tg. g Its performance characteristics. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an epoxy resin curing agent with dual activity. The epoxy resin / curing agent composition has good room temperature thickening properties, storage stability, rapid curing ability at medium and high temperatures, and high mechanical and heat resistance properties. It can be prepared into epoxy resin composite materials with good temperature resistance through various composite material molding processes, especially in the field of SMC compression molding applications.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] On one hand, the present invention provides an epoxy resin curing agent, the curing agent having the following structural formula:

[0010]

[0011] The method for preparing the curing agent includes the following steps:

[0012] Urea, hydrochloric acid, water, and 4-[(4-aminocyclohexane)methyl]aniline were added sequentially to a three-necked flask. After stirring, the system was thoroughly mixed. The mixture was heated to reflux. After the reflux reaction was completed, hydrochloric acid was added and the mixture was kept warm and stirred. After the reaction was completed, the mixture was filtered and dried to obtain a pure 4-(4-aminobenzyl)cyclohexylurea product.

[0013] Preferably, the molar ratio of 4-[(4-aminocyclohexane)methyl]aniline, urea, hydrochloric acid, and water is 1:(0.7-1.8):(0.5-3):(10-30), more preferably 1:(0.9-1.3):(1-1.5):(18-25).

[0014] Preferably, the heating method is one or more of oil bath, water bath, air bath, etc., with oil bath being the preferred method.

[0015] Preferably, the reflux reaction temperature is 80-110℃, more preferably 100-110℃.

[0016] Preferably, the reflux reaction time is 1-5 hours, more preferably 1-3 hours.

[0017] Preferably, the hydrochloric acid has a mass fraction of 5%-15%, more preferably 5%-10%.

[0018] Preferably, the amount of hydrochloric acid added is 0.8 to 1.2 times the amount of hydrochloric acid added initially.

[0019] Preferably, the heat preservation and stirring time is 1-3 hours, more preferably 1-2 hours.

[0020] Preferably, the drying temperature is 40-100℃ and the drying time is 2-10h.

[0021] On the other hand, the present invention provides an epoxy resin composition comprising the following components:

[0022] A) Bisphenol A type epoxy resin;

[0023] B) Bisphenol F type epoxy resin;

[0024] C) Reactive diluent;

[0025] D) 4-(4-aminobenzyl)cyclohexylurea

[0026]

[0027] Preferably, the epoxy value of the bisphenol A type epoxy resin is 0.2-0.8, more preferably 0.4-0.6; and the epoxy value of the bisphenol F type epoxy resin is 0.2-0.8, more preferably 0.4-0.6.

[0028] Preferably, the bisphenol A type epoxy resin is selected from one or more of DER 331, DER 337, and DER 662E, with DER 331 being preferred; the bisphenol F type epoxy resin is selected from one or two of NPEF-170, DER 354, and DER 351, with NPEF-170 being preferred.

[0029] Preferably, the active diluent is one or more of C12-14 glycidyl ether (AGE), benzyl glycidyl ether (692), butanediol diglycidyl ether (622), and trimethylolpropane triglycidyl ether (636), with C12-14 glycidyl ether (AGE) being the most preferred.

[0030] Preferably, the mass ratio of A) bisphenol A type epoxy resin; B) bisphenol F type epoxy resin; and C) reactive diluent is (50-90):(5-30):(5-20), more preferably (70-80):(10-20):(5-10).

[0031] Preferably, the mass ratio of the sum of the masses of A) bisphenol A type epoxy resin, B) bisphenol F type epoxy resin, and C) reactive diluent (A+B+C) to the mass of the curing agent is 100:(20-40), more preferably 100:(25-35).

[0032] On the other hand, the present invention provides an epoxy resin composite material, the preparation method of which includes the following steps: compounding an epoxy resin composition with fibers and then heating and curing it.

[0033] Preferably, the fiber is selected from one or more of carbon fiber, glass fiber, bamboo fiber, and aramid fiber, with glass fiber being the most preferred;

[0034] Preferably, the molding method is selected from one or more of SMC molding process, filament winding process, pultrusion molding process, and prepreg molding process, with SMC molding process being preferred;

[0035] The mass ratio of the epoxy resin composition to the fiber is 1:(2-6), preferably 1:(3-5);

[0036] Preferably, during the heat curing process, the epoxy resin first reacts with 4-(4-aminobenzyl)cyclohexylurea curing agent at low temperature to reach the "B stage", and then the post-curing reaction of the epoxy resin is achieved by heating.

[0037] Preferably, the reaction temperature at low temperature is 15-50℃, more preferably 25-40℃; the reaction time is 5h-168h, more preferably 24-120h.

[0038] Preferably, the post-curing temperature of the epoxy resin composite material is 80-130℃ and the time is 1-120 min, and more preferably the temperature is 100-120℃ and the time is 5-30 min.

[0039] Finally, this invention also provides applications of epoxy resin composite materials in fields such as wind turbine blades, pressure vessels, and automotive parts.

[0040] The beneficial effects of this invention are as follows:

[0041] (1) Urea modification of alicyclic amines is simpler to synthesize than alkylation modification, improves molecular functionality, and serves as a curing agent for epoxy resins to increase the crosslinking density of the cured product, thereby making a significant contribution to improving its mechanical properties and heat resistance. It is more suitable for the field of high-performance composite materials.

[0042] (2) The curing agent system with dual reactivity of 4-(4-aminobenzyl)cyclohexylurea utilizes the reaction of highly active urea groups with epoxy resin for thickening under low temperature conditions in the early stage. Compared with traditional latent curing agents, no additional thickener is required, the process is simple and the production efficiency is high. In the later stage, the aromatic amine and epoxy resin are cured and crosslinked under medium and high temperature conditions. Compared with traditional latent curing agents, the curing temperature is low and the speed is fast, and it has good process adaptability.

[0043] (3) Compared to traditional latent curing agents (such as dicyandiamide), 4-(4-aminobenzyl)cyclohexylurea has good compatibility with epoxy resin, which is beneficial to the uniform dispersion and curing of epoxy resin / curing agent. The latent mechanism is fundamentally different from that of traditional latent curing agents. Traditional latent curing agents have low activity, high reaction activation energy, and high process requirements; 4-(4-aminobenzyl)cyclohexylurea has both active hydrogen and inert hydrogen. After the active hydrogen and epoxy resin have initially cured, the molecular chains are frozen and difficult to move, effectively preventing further ring-opening reactions of inert hydrogen, resulting in a better latent effect and extending the storage stability period. After the temperature rises, the molecular chains begin to move, and inert hydrogen participates in the ring-opening cross-linking reaction of epoxy resin, improving the degree of curing. Attached Figure Description

[0044] Figure 1 The infrared spectrum of 4-(4-aminobenzyl)cyclohexylurea;

[0045] Figure 2 The curing reaction thermal curve of epoxy resin / curing agent in Example 1 is shown. Detailed Implementation

[0046] The present invention will be further illustrated by specific embodiments. These embodiments are merely illustrative and do not limit the scope of the invention.

[0047] For details on raw materials and their sources, please refer to Table 1.

[0048] Table 1 Raw Materials and Sources

[0049] Chemical name factory Bisphenol A type epoxy resin (DER 331) Dow Chemical Company Bisphenol A type epoxy resin (DER 337) Dow Chemical Company Bisphenol A type epoxy resin (DER 662E) Dow Chemical Company Bisphenol F type epoxy resin (DER 354) Dow Chemical Company Bisphenol F type epoxy resin (DER 351) Dow Chemical Company Aliphatic glycidyl ethers (AGE, 692, 622, 636) Anhui Xinyuan Technology Co., Ltd. <![CDATA[4-((4-Aminocyclohexyl)methyl)aniline (H6MDA)]]> Wanhua Chemical Group Co., Ltd. 4,4-Diaminodiphenylmethane (MDA) Wanhua Chemical Group Co., Ltd. Dicyandiamide (DICY) Sigma-Aldrich Biotechnology Co., Ltd. Silane coupling agent (Z-6040) Dow Corning Incorporated

[0050] Unless otherwise specified, all other ingredients are commercially available products.

[0051] Synthesis of curing agent 4-(4-aminobenzyl)cyclohexylurea:

[0052] Urea, hydrochloric acid, water, and 4-[(4-aminocyclohexane)methyl]aniline were added sequentially to a three-necked flask. After stirring, the system was thoroughly mixed and heated. Once the temperature rose, the solvent began to reflux, and then hydrochloric acid was added to maintain the temperature while stirring. After the reaction was complete, the mixture was filtered and dried to obtain pure 4-(4-aminobenzyl)cyclohexylurea product.

[0053] Preparation Example 1

[0054] Add 6g of urea to a 250ml three-necked flask, followed by 36g of 10% hydrochloric acid, 36g of water, and 24.7g of 4-[(4-aminocyclohexane)methyl]aniline. After stirring, the system is thoroughly mixed and heated to 106℃. Once the temperature rises, the solvent is refluxed for 2 hours, then 36g of 10% hydrochloric acid is added and the mixture is stirred for another 2 hours. After the reaction is complete, the system is cooled to room temperature and filtered to obtain a white solid product. This solid product is then dried in a vacuum oven at 70℃ under a vacuum of 0.1MPa to obtain a pure 4-(4-aminobenzyl)cyclohexylurea product.

[0055] Preparation Example 2

[0056] 4.2 g of urea was added to a 500 ml three-necked flask, followed by 108 g of 5% hydrochloric acid, 18 g of water, and 24.7 g of 4-[(4-aminocyclohexane)methyl]aniline. After stirring, the mixture was thoroughly mixed and heated to 100 °C. The solvent was then refluxed for 5 h after the temperature rose, followed by the addition of 108 g of 10% hydrochloric acid and stirring for 3 h. After the reaction was complete, the mixture was allowed to cool to room temperature and filtered to obtain a white solid product. This solid product was then dried in a vacuum oven at 70 °C under a vacuum of 0.1 MPa to obtain a pure 4-(4-aminobenzyl)cyclohexylurea product.

[0057] Preparation Example 3

[0058] 10.8 g of urea was added to a 100 ml three-necked flask, followed by 18 g of 5% hydrochloric acid, 54 g of water, and 24.7 g of 4-[(4-aminocyclohexane)methyl]aniline. After stirring, the mixture was thoroughly mixed and heated to 110 °C. Once the temperature had risen, the solvent was refluxed for 1 hour, and then 18 g of 10% hydrochloric acid was added and the mixture was stirred for another 1 hour. After the reaction was complete, the mixture was allowed to cool to room temperature and filtered to obtain a white solid product. This solid product was then dried in a vacuum oven at 70 °C under a vacuum of 0.1 MPa to obtain a pure 4-(4-aminobenzyl)cyclohexylurea product.

[0059] Example 1

[0060] (1) The epoxy resin composition is prepared by mass fraction as follows: 50g of bisphenol A type epoxy resin (DER 331), 30g of bisphenol F type epoxy resin (DER 354), 20g of C12-14 glycidyl ether (AGE), 0.2g of silane coupling agent (Z-6040), and 25g of 4-(4-aminobenzyl)cyclohexylurea. The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08MPa and a temperature of 25℃ to remove air bubbles.

[0061] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 15°C for 168 hours to reach the "B stage" state. Then, it is heated and cured at 80°C for 120 minutes in a blower oven to obtain the cured epoxy resin casting. Test strips are prepared by engraving machine.

[0062] Example 2

[0063] (1) The epoxy resin composition is prepared by mass fraction as follows: 90g of bisphenol A type epoxy resin (DER 337), 5g of bisphenol F type epoxy resin (DER 351), 5g of benzyl glycidyl ether (692), 0.2g of silane coupling agent (Z-6040), and 35g of 4-(4-aminobenzyl)cyclohexylurea. The mixture is added to a 250mL round bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08Mpa and a temperature of 25℃.

[0064] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 50°C for 5 hours to reach the "B stage" state. Then, it is heated at 130°C in a blower oven for 5 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0065] Example 3

[0066] (1) The epoxy resin composition is prepared by mass fraction as follows: 80g of bisphenol A type epoxy resin (DER 331), 10g of bisphenol F type epoxy resin (DER 354), 10g of 1,4-butanediol diglycidyl ether (622), 0.2g of silane coupling agent (Z-6040), and 27g of 4-(4-aminobenzyl)cyclohexylurea. The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08MPa and a temperature of 25℃ to remove air bubbles.

[0067] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 30°C for 100 hours to reach the "B stage" state. Then, it is heated at 110°C in a blower oven and cured for 60 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0068] Example 4

[0069] (1) The epoxy resin composition is prepared by mass fraction as follows: 80g of bisphenol A type epoxy resin (DER 662E), 10g of bisphenol F type epoxy resin (DER 351), 10g of 1,4-butanediol diglycidyl ether (AGE), 0.2g of silane coupling agent (Z-6040), and 27g of 4-(4-aminobenzyl)cyclohexylurea. The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08MPa and a temperature of 25℃ to remove air bubbles.

[0070] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 25°C for 120 hours to reach the "B stage" state. Then, it is heated and cured at 120°C for 30 minutes in a blower oven to obtain the cured epoxy resin casting. Test strips are prepared by engraving machine.

[0071] Comparative Example 1:

[0072] (1) The epoxy resin composition is prepared by mass fraction as follows: 80g of bisphenol A type epoxy resin (DER 331), 10g of bisphenol F type epoxy resin (DER 354), 10g of 1,4-butanediol diglycidyl ether (622), 0.2g of silane coupling agent (Z-6040), and 10g of dicyandiamide (DICY). The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08Mpa and a temperature of 25℃ to remove air bubbles.

[0073] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 30°C for 100 hours to reach the "B stage" state. Then, it is heated at 110°C in a blower oven and cured for 60 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0074] Comparative Example 2:

[0075] (1) The epoxy resin composition is prepared by mass fraction as follows: 80g of bisphenol A type epoxy resin (DER 331), 10g of bisphenol F type epoxy resin (DER 354), 10g of 1,4-butanediol diglycidyl ether (622), 0.2g of silane coupling agent (Z-6040), and 10g of dicyandiamide (DICY). The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08Mpa and a temperature of 25℃ to remove air bubbles.

[0076] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 80°C for 5 hours to reach the "B stage" state. Then, it is heated at 150°C in a blower oven for 60 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0077] Comparative Example 3

[0078] (1) The epoxy resin composition is prepared by mass fraction as follows: 80g of bisphenol A type epoxy resin (DER 331), 10g of bisphenol F type epoxy resin (DER 354), 10g of 1,4-butanediol diglycidyl ether (622), 0.2g of silane coupling agent (Z-6040), and 28g of 4,4-diaminodiphenylmethane (MDA). The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08MPa and a temperature of 25℃ to remove air bubbles.

[0079] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 30°C for 100 hours to reach the "B stage" state. Then, it is heated at 110°C in a blower oven and cured for 60 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0080] Comparative Example 4

[0081] (1) The epoxy resin composition is prepared by mass fraction as follows: 80g of bisphenol A type epoxy resin (DER 331), 10g of bisphenol F type epoxy resin (DER 354), 10g of 1,4-butanediol diglycidyl ether (622), 0.2g of silane coupling agent (Z-6040), and 28g of 4,4-diaminodiphenylmethane (MDA). The mixture is added to a 250mL round-bottom flask and stirred evenly with a mechanical stirrer. The mixture is then dried in a vacuum drying oven at a vacuum degree of 0.08MPa and a temperature of 25℃ to remove air bubbles.

[0082] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 50°C for 5 hours to reach the "B stage" state. Then, it is heated at 150°C in a blower oven for 60 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0083] Comparative Example 5

[0084] (1) The epoxy resin composition is made by weighing 80g of bisphenol A type epoxy resin (DER 331), 10g of bisphenol F type epoxy resin (DER 354), 10g of 1,4-butanediol diglycidyl ether (622), 0.2g of silane coupling agent (Z-6040), and 65g of 4-aminobenzyl-4-aminocyclohexane reduced alkylate (synthesis method refers to patent CN101654504B) into a 250mL round bottom flask. The system composition is mixed evenly by mechanical stirring paddle, and the air bubbles are removed by vacuum drying oven with a vacuum degree of 0.08Mpa and a temperature of 25℃.

[0085] (2) Heating and curing: The epoxy resin composition obtained in step (1) is poured into a sealed glass mold and placed at 30°C for 100 hours to reach the "B stage" state. Then, it is heated at 110°C in a blower oven and cured for 60 minutes to obtain the cured epoxy resin casting. The test strip is prepared by a carving machine.

[0086] Table 2 Comparison of Curing Performance of Epoxy Resin Compositions

[0087] Example Mixed viscosity <![CDATA[B-stage state (T g )]]> Storage period Tensile strength Bending strength Heat distortion temperature 1 953cP 33℃ ≥45d 72MPa 112MPa 122℃ 2 1161cP 44℃ ≥45d 87MPa 129MPa 145℃ 3 1031cP 37℃ ≥45d 81MPa 116MPa 119℃ 4 1272cP 40℃ ≥45d 85MPa 127MPa 131℃ Comparative Example 1 2894cP Flow dynamics — 33MPa 76MPa 51℃ Comparative Example 2 2897cP 16℃ ≥90d 63MPa 106MPa 101℃ Comparative Example 3 1763cP Flow dynamics — 73MPa 109MPa 115℃ Comparative Example 4 1832cP 29℃ ≥15d 81MPa 121MPa 143℃ Comparative Example 5 6371cP viscous liquid — 45MPa 76MPa 84℃

[0088] The above-mentioned mixed viscosity was measured using a rotational viscometer; T in the "B-order" state g Determined by DSC; in this scheme, the storage period is defined as the time (T) required to maintain the "Level B" state at 25°C. g (Unchanged); tensile strength was determined according to ISO 527-2; flexural strength was determined according to ISO 178; heat distortion temperature was determined according to ISO 75-2.

Claims

1. An epoxy resin curing agent, having the following structural formula:

2. The method for preparing an epoxy resin curing agent according to claim 1, wherein comprising the following steps: adding urea, hydrochloric acid, water and 4-[(4-aminocyclohexane) methyl] aniline into a three-necked flask in sequence, stirring and mixing the system thoroughly; heating and refluxing the reaction, adding hydrochloric acid after the refluxing reaction is completed and stirring under heat preservation; filtering and drying the product to obtain pure 4-[(4-aminocyclohexane) methyl] aniline. 4-[(4-aminocyclohexane) methyl] aniline, urea, hydrochloric acid and water are in a molar ratio of 1: (0.7-1.8) : (0.5-3) : (10-30).

3. The production method according to claim 2, wherein 4-[(4-aminocyclohexane) methyl] aniline, urea, hydrochloric acid and water are in a molar ratio of 1: (0.9-1.3) : (1-1.5) : (18-25).

4. The production method according to claim 2, wherein The refluxing reaction temperature is 80-110℃, the refluxing reaction time is 1-5h; and / or, the heat preservation stirring time is 1-3h.

5. The production method according to claim 2 or 3, characterized by, The refluxing reaction temperature is 100-110℃, the refluxing reaction time is 1-3h; and / or, the heat preservation stirring time is 1-2h.

6. The production method according to claim 2 or 3, wherein 7.An epoxy resin composition, comprising the following components: A) a bisphenol A type epoxy resin; B) a bisphenol F type epoxy resin; C) an active diluent; D) an epoxy resin curing agent, The epoxy resin curing agent is selected from the epoxy resin curing agent of claim 1 or the epoxy resin curing agent prepared by the preparation method of any one of claims 2-6. The bisphenol A type epoxy resin has an epoxy value of 0.2-0.8; the bisphenol F type epoxy resin has an epoxy value of 0.2-0.8; the bisphenol A type epoxy resin is selected from one or more of DER 331, DER 337 and DER 662E; the bisphenol F type epoxy resin is selected from one or two of NPEF-170, DER 354 and DER 351.

8. The epoxy resin composition according to claim 7, wherein The bisphenol A type epoxy resin has an epoxy value of 0.4-0.6; the bisphenol F type epoxy resin has an epoxy value of 0.4-0.

6.

9. The epoxy resin composition according to claim 7, wherein The active diluent is one or more of C12-14 glycidyl ether (AGE), benzyl glycidyl ether (692), butanediol diglycidyl ether (622) and trimethylolpropane triglycidyl ether (636).

10. The epoxy resin composition according to any one of claims 7 to 9, wherein The mass ratio of the A) bisphenol A type epoxy resin; B) bisphenol F type epoxy resin; C) active diluent is (50-90) : (5-30) : (5-20) ; and / or, the mass ratio of the A) bisphenol A type epoxy resin, B) bisphenol F type epoxy resin, C) active diluent to the curing agent is 100: (20-40).

11. The epoxy resin composition according to any one of claims 7 to 9, wherein The mass ratio of the A) bisphenol A type epoxy resin; B) bisphenol F type epoxy resin; C) active diluent is (70-80) : (10-20) : (5-10) ; and / or, the mass ratio of the A) bisphenol A type epoxy resin, B) bisphenol F type epoxy resin, C) active diluent to the curing agent is 100: (25-35).

12. The epoxy resin composition according to any one of claims 7 to 9, wherein ​ 13. An epoxy resin composite material obtained by molding and curing an epoxy resin composition and a fiber; the epoxy resin composition is selected from the epoxy resin composition according to any one of claims 7-12; the mass ratio of the epoxy resin composition to the fiber is 1:(2-6).

14. An epoxy resin composite material obtained by molding and curing an epoxy resin composition and a fiber; the epoxy resin composition is selected from the epoxy resin composition according to any one of claims 7-12; the mass ratio of the epoxy resin composition to the fiber is 1:(3-5).

15. Use of the epoxy resin composite material according to claim 13 or 14 in the field of wind power blades, pressure vessels, automobile parts.

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