A weather-resistant resin system suitable for forming a 66kV carbon fiber repair tower and a preparation method thereof

Abstract

The application relates to the technical field of high polymer composite materials, and discloses a weather-resistant resin system suitable for forming a 66kV carbon fiber repair tower and a preparation method thereof, which is prepared by mixing component A, component B and component C at a mass ratio of 100:(90-105):(4-10). Component A comprises bisphenol A type and bisphenol F type epoxy resins, glycidyl ether diluents containing epoxy groups, epoxy type first toughening agents and silane coupling agents and the like; component B comprises a composite acid anhydride curing agent and a double accelerator; and component C comprises a second toughening agent. According to the application, the active diluent is covalently connected to the crosslinking network, the migration path of small molecules is cut off, and the weather resistance is improved; the double-toughening structure is adopted to improve the impact toughness; the normal-temperature latency and high-temperature catalytic characteristics of the double-accelerator system are utilized, and the long applicable period and high-temperature rapid curing are considered. The application has excellent comprehensive mechanical properties and can meet the forming requirements of the carbon fiber repair tower under the severe outdoor environment.

Description

Technical Field

[0001] This invention relates to the field of polymer composite materials technology, specifically to a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method. Background Technology

[0002] When power transmission lines are damaged by natural disasters such as typhoons and ice storms, emergency repair towers are needed for rapid restoration. Carbon fiber composite materials, due to their lightweight and high specific strength, are increasingly being used in the manufacture of main poles for 66kV and above emergency repair towers. In composite material components, the comprehensive performance of the resin matrix directly determines the interlaminar shear strength, impact resistance, and long-term service life in complex outdoor environments.

[0003] Emergency repair towers typically operate in harsh outdoor environments, facing long-term exposure to high temperatures, high humidity, ultraviolet radiation, and salt spray corrosion. Existing conventional two-component epoxy resin systems have relatively simple cross-linking networks. To meet the viscosity requirements of molding large-sized components, a significant amount of inactive diluents is usually added to the formulation. These free, inactive small molecules, driven by long-term thermal stress and moisture gradients, easily migrate and volatilize, leaving micropores within the matrix. These pores not only disrupt the density of the cross-linking network but also provide diffusion channels for the penetration of moisture and corrosive ions from the environment, easily triggering matrix degradation and interfacial damage, leading to a significant decline in the macroscopic mechanical strength of the composite material.

[0004] Furthermore, in practical applications, emergency repair towers need to withstand dynamic alternating loads such as wind loads, as well as external collisions during transportation and loading / unloading. Existing high-strength resin systems often have high cross-linking densities to maintain high heat resistance, resulting in significantly brittle characteristics in the cured product. When components are subjected to external impact, internal stress cannot be effectively released, easily inducing rapid propagation of microcracks and leading to brittle fracture. While simply introducing conventional flexible toughening agents into the system can improve toughness to some extent, it often comes at the cost of sacrificing the material's glass transition temperature and stiffness, making it difficult to achieve a balance between rigidity and flexibility.

[0005] In the molding and manufacturing process, the main shaft of the emergency repair tower mostly adopts a large-tow carbon fiber winding process. This process requires the resin system to have a low viscosity and a long pot life during the room temperature impregnation stage to ensure that the resin can fully penetrate into the fiber tow and displace air. However, the accelerators used in existing resin systems often have high catalytic activity at room temperature, and slow pre-crosslinking polymerization begins immediately after the raw materials are mixed, resulting in a rapid increase in system viscosity and a shorter pot life. If the pot life is extended by reducing the amount of accelerator, the crosslinking reaction will be slow in the high-temperature stage after entering the curing oven, which cannot meet the production requirements of rapid molding of emergency repair equipment. At the same time, the existing basic resin formulation has limited physical wetting and chemical bonding capabilities on the carbon fiber surface, and the interfacial bonding force between the resin and fiber after curing is weak, making it prone to interlaminar shear failure under load. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method, solving the problems of insufficient weather resistance, poor impact toughness, and difficulty in simultaneously achieving short room temperature service life and rapid high-temperature curing in existing carbon fiber emergency repair tower resin matrices.

[0007] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers, employing the following technical solution: A weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers is prepared by mixing components A, B, and C in a mass ratio of 100:(90-105):(4-10). Component A is made from raw materials containing the following parts by weight: 50-80 parts of bisphenol A type epoxy resin; 10-40 parts of bisphenol F type epoxy resin; 5-15 parts of glycidyl ether diluent containing epoxy groups; 10-20 parts of epoxy primary toughening agent; 0.1-0.5 parts of silane coupling agent; and 1-5 parts of release agent. Component B is made from raw materials containing the following parts by weight: 50-70 parts of methyltetrahydrophthalic anhydride; 30-50 parts of methylnadic anhydride; 0.5-1.5 parts of 2-ethyl-4-dimethylimidazole; and 0.2-0.5 parts of 2,4,6-tris(dimethylaminomethyl)phenol. Component C is made from raw materials containing the following parts by weight: 4-10 parts of secondary toughening agent.

[0008] By adopting the above technical solution, this invention constructs a resin matrix that combines high weather resistance, ultra-high impact toughness, and rapid curing characteristics with a long pot life. The internal microscopic reaction process and mechanism of action are detailed in the following steps: (1) The molecular network construction and weather resistance mechanism system adopts bisphenol A and bisphenol F epoxy resins as the basic compound, and utilizes the low viscosity of bisphenol F molecules to improve the initial mobility of polymer chain segments. Glycidyl ether diluents containing epoxy groups are introduced into component A. While adjusting the rheological properties of the resin, the end groups of this type of diluent contain active epoxy functional groups. During the high-temperature curing stage, the active groups directly participate as comonomers in the ring-opening esterification crosslinking reaction of the anhydride in component B, and become part of the three-dimensional network structure in the form of covalent bonds. The anchoring effect of chemical bonds fundamentally eliminates the possibility of the existence of inactive small molecules in a free state, and cuts off the outward migration path of small molecules driven by long-term thermal stress and moisture gradient. This prevents the formation of micro-pores and interface defects inside the matrix, blocks the physical channels for environmental moisture, oxygen and salt spray ions to penetrate into the depth of the network, and realizes a leap in the weather resistance of the material. Meanwhile, methyltetrahydrophthalic anhydride in component B provides basic reactivity and crosslinking density, while methylnadic anhydride introduces rigid segments into the crosslinking network through its intramolecular bridged ring skeleton structure. The two work together to form a composite anhydride network, which restricts the slippage of macromolecular chain segments at high temperatures and further enhances the heat resistance and degradation resistance of the cured product.

[0009] (2) The bidirectional synergistic toughening mechanism system pre-installs toughening components of different dimensions in components A and C, forming a dual energy-consuming structure at the molecular and phase levels. The epoxy-based first toughening agent in component A has a long-chain flexible structure and terminal epoxy groups. During curing, it directly connects to the main network, increases the free volume of the internal structure, and completes stress release and deformation coordination at the molecular level. As the depth of the curing reaction increases, the molecular weight of the system continues to increase, triggering thermodynamic incompatibility. The second toughening agent in component C undergoes microphase separation in the matrix, agglomerating into a microscale dispersed phase distributed in the continuous epoxy matrix, forming an island structure. When the material is subjected to external high-speed alternating or impact loads, the stress field is concentrated and redistributed at the dispersed phase interface, inducing a large number of crazes in the matrix and promoting local shear yielding of the resin around the dispersed phase particles. The branching of the crazes and the plastic deformation process of the shear bands absorb and consume the energy of crack propagation, solving the physical contradiction of brittle fracture in high cross-linking density resin systems.

[0010] (3) Dual-control mechanism of curing kinetics: Component B employs a dual-accelerator system composed of 2-ethyl-4-dimethylimidazole and 2,4,6-tris(dimethylaminomethyl)phenol. Under ambient temperature conditions, the two interact to form a chemical complex. The steric hindrance of the complex structure masks the catalytic active center, exhibiting latent characteristics. At this stage, the ring-opening esterification reaction between the epoxy group and the acid anhydride is inhibited, and the system macroscopically exhibits slow viscosity growth, providing a suitable time window for the impregnation and molding of large-tow carbon fibers. When the ambient temperature jumps to the set curing temperature, thermodynamic conditions trigger the rapid dissociation of the complex, and the dual accelerators produce a synergistic catalytic effect, changing the activation energy path of the crosslinking reaction, prompting the liquid resin to rapidly complete the phase transition, reach the gel point, and achieve rapid curing.

[0011] (4) Interfacial Covalent Bonding Mechanism: The silane coupling agent contained in component A participates in the interfacial construction of the composite material. The polar group at one end undergoes an addition reaction with the epoxy group during the curing process of the resin matrix, while the siloxane group at the other end undergoes a condensation reaction with the hydroxyl and other polar groups on the surface of the reinforcing carbon fiber after hydrolysis. This chemical reaction establishes a covalent bond connection at the phase interface between the inorganic carbon fiber and the organic resin, forming a stress transfer gradient layer and improving the interlaminar shear strength of the composite material after molding.

[0012] Preferably, in component A, the glycidyl ether diluent containing epoxy groups is epoxyNovak glycidyl ether, and the silane coupling agent is γ-aminopropyltriethoxysilane. By employing the above technical solution, epoxyNovak glycidyl ether possesses a multifunctional structure, which, while reducing viscosity, provides more crosslinking nodes to compensate for the decrease in crosslinking density caused by the introduction of flexible segments. The primary amino group at the molecular end of γ-aminopropyltriethoxysilane has activity that matches the ring-opening reaction kinetics of the epoxy system, ensuring that the interfacial chemical bonds and the matrix curing network are constructed synchronously.

[0013] Preferably, in component C, the second toughening agent is liquid nitrile rubber, or a compound of polyether polyol and solid rubber mixed in a mass ratio of (4-6):(2-4). By adopting the above technical solution, the polarity of the liquid nitrile rubber is close to that of the epoxy resin matrix, which can achieve good early-stage miscibility and later-stage uniform phase separation. By using a compound of polyether polyol and solid rubber, and utilizing the difference in molecular weight and solubility parameters between the two, a wide-scale microphase separation multi-level particle size distribution is formed in the matrix, further broadening the frequency band range for the material to absorb impact load energy.

[0014] Preferably, in component A, the mass ratio of bisphenol A epoxy resin to bisphenol F epoxy resin is (50-60):(30-40); the mass ratio of components A, B, and C is 100:96:4. By adopting the above technical solution and limiting the compounding ratio of the base resin, the initial rheological properties of the system at room temperature are maintained at a low viscosity, ensuring the capillary permeation pressure during the carbon fiber impregnation process. Defining the total mass ratio of the three components ensures that the stoichiometric coefficients of the anhydride groups and epoxy groups are balanced, resulting in very few unreacted free groups in the cured network and maximizing the mechanical strength of the cured product.

[0015] Preferably, in component B, the mass ratio of methyltetrahydrophthalic anhydride to methylnadic anhydride is (60-70):(30-40); and the mass ratio of 2-ethyl-4-dimethylimidazolium to 2,4,6-tris(dimethylaminomethyl)phenol is (3-4):1. By adopting the above technical solution, the pre-defined proportions of the anhydride formulation ensure that the flexible base segments and rigid bridging ring skeleton in the cured network achieve the expected ratio as designed mechanically. Limiting the mass ratio of the two accelerators ensures that they can form a sufficient amount of room-temperature latent complex according to the stoichiometric ratio, preventing a shortened pot life due to excessive release of a single catalyst.

[0016] Preferably, in component A, the release agent is a stearic acid-based internal release agent. By adopting the above technical solution, the stearic acid-based internal release agent migrates to the surface of the product in the later stage of high-temperature curing, forming a microscopic isolation layer, reducing the frictional force when the composite material component is demolded, and does not interfere with the resin-fiber interface wetting process in the early stage of curing.

[0017] Secondly, the present invention provides a method for preparing a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers, using the following technical solution: A method for preparing a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers includes the following steps: Bisphenol A type epoxy resin, bisphenol F type epoxy resin, and glycidyl ether diluent containing epoxy groups were mixed and stirred. Then, an epoxy-based first toughening agent was added and mixed and matured. Finally, a silane coupling agent and a release agent were added and mixed and stirred. After cooling, component A was obtained. Methyltetrahydrophthalic anhydride, methylnadic anhydride, 2-ethyl-4-dimethylimidazole, and 2,4,6-tris(dimethylaminomethyl)phenol were mixed and stirred. After cooling, component B was obtained. The second toughening agent was stirred at a constant temperature and cooled to obtain component C. The above-prepared components were taken separately and mixed evenly according to the corresponding mass ratio to obtain a weather-resistant resin system.

[0018] By employing the above technical solution and a three-component separation preparation process, the main resin, composite anhydride curing agent, and additives with different chemical activities are physically isolated and stored separately. This avoids the disorderly competitive reaction and microscopic pre-crosslinking polymerization of silane coupling agents containing primary amino groups and toughening agent components with active hydrogens with epoxy groups or anhydrides at room temperature under conventional one-pot mixing conditions. Physical isolation cuts off the side reaction chain, ensures the rheological stability of the original solution system, avoids a sharp increase in viscosity during the mixing stage, and reserves sufficient operating time for the subsequent impregnation molding process of large-size carbon fiber composite components.

[0019] Preferably, in the step of preparing component A, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and glycidyl ether diluent are mixed and stirred at 60-70°C for 3-5 hours; after adding the epoxy-based first toughening agent, the mixture is further mixed and cured at 60-70°C for 4-5 hours; finally, the silane coupling agent and release agent are added, and the mixture is stirred at 60-70°C for 10-20 minutes. By adopting the above technical solution, the staged temperature-controlled mixing ensures the full expansion and miscibility of the molecular chains of the base resin and the diluent. The intermediate stage of constant temperature curing allows the first toughening agent to be uniformly inserted into the base resin matrix. The final stage shortens the stirring time and controls the temperature to prevent the coupling agent from prematurely hydrolyzing and failing due to prolonged heating.

[0020] Preferably, in the step of preparing component B, the reaction temperature is controlled at 50-60℃ and the stirring time is 100-150 minutes; in the step of preparing component C, the stirring temperature is controlled at 45-55℃ and the stirring time is 20-30 minutes. By adopting the above technical solution, the temperature-controlled stirring parameters of component B eliminate the crystal phase agglomeration phenomenon during solid acid anhydride mixing and promote the complexation reaction between the two promoter molecules. The temperature control of component C ensures that the high-viscosity toughening agent is in a suitable flow state, achieving a homogeneous distribution of the internal molecular structure.

[0021] Preferably, the step of uniformly mixing the components involves weighing and mixing components A, B, and C, then stirring at a constant temperature of 70-80℃ for 20-30 minutes. By adopting the above technical solution, the three components are finally mixed at a slightly heated state of 70-80℃ before actual construction. This temperature effectively reduces the overall dynamic viscosity of the mixture and enhances the diffusion coefficient between the fluid components. The short stirring time achieves both molecular-level homogeneous mixing of the formulation system and keeps the system in the curing induction phase, providing a good hydrodynamic basis for the subsequent control of carbon fiber adhesive content and in-mold defoaming process.

[0022] This invention provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method. It has the following beneficial effects: 1. This invention introduces a glycidyl ether diluent containing epoxy groups into component A, allowing it to directly participate as a comonomer in the crosslinking reaction of the composite anhydride in component B during the curing stage. By utilizing the anchoring effect of chemical covalent bonds, the presence of free small molecules inside the matrix is ​​eliminated, cutting off the migration and volatilization paths of small molecules under hot and humid conditions, avoiding the formation of microscopic interfacial pores, and blocking the physical channels for the diffusion of environmental moisture and salt spray ions into the matrix, thereby improving the weather resistance of the resin system and the corresponding carbon fiber composite components in harsh outdoor environments.

[0023] 2. This invention constructs a dual toughening structure with molecular-level and microphase separation. The epoxy-based first toughening agent in component A is directly integrated into the crosslinking network to increase the internal free volume. At the same time, the second toughening agent in component C undergoes thermodynamic incompatibility during resin curing, resulting in microphase separation and the formation of dispersed phase particles. When the material is subjected to external impact loads, the phase interface of the dispersed phase particles can induce a large number of crazes in the matrix and promote local shear yielding, thereby absorbing and consuming the energy required for crack propagation. This solves the physical contradiction that high crosslinking density resin systems are prone to brittle fracture under stress, and improves the mechanical strength and impact toughness after curing.

[0024] 3. This invention employs a three-component physically isolated preparation process, combined with a dual-accelerator system of 2-ethyl-4-dimethylimidazole and 2,4,6-tris(dimethylaminomethyl)phenol in component B. This achieves bidirectional control of curing kinetics. At room temperature, a sterically hindered complex is formed to inhibit the crosslinking reaction, avoiding spontaneous pre-crosslinking after multi-component mixing. This maintains the resin system at a low viscosity and a long pot life, ensuring the physical wetting effect of the carbon fiber. Under high-temperature curing conditions, the complex rapidly dissociates, generating a synergistic catalytic effect, prompting the resin system to quickly reach the gel point and complete crosslinking, thus meeting the process requirements for high-efficiency molding of carbon fiber emergency repair tower components. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the embodiments and comparative examples. 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.

[0026] Preparation Examples 1-3: Preparation Example 1: This preparation example provides a method for preparing a weather-resistant resin system suitable for molding a 66kV carbon fiber emergency repair tower, including the following steps: 60 parts by weight of bisphenol A type epoxy resin E51, 30 parts by weight of bisphenol F type epoxy resin NPEF-170, and 5 parts by weight of epoxy Novak glycidyl ether were mixed and stirred at 60°C for 4 hours; 13 parts by weight of epoxy toughening agent WD-508 were added, and the mixture was further mixed and cured at 60°C for 4.5 hours; 0.1 parts by weight of γ-aminopropyltriethoxysilane and 1 part by weight of stearic acid release agent CLI7011 were added, and the mixture was stirred at 60°C for 10 minutes; the mixture was cooled to room temperature to obtain component A.

[0027] 58.2 parts by weight of methyltetrahydrophthalic anhydride and 38.8 parts by weight of methylnadic anhydride (total of 97 parts by weight of composite curing agent, with a mass ratio of 60:40) were mixed with 0.75 parts by weight of 2-ethyl-4-dimethylimidazole and 0.25 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol at 55°C for 120 minutes; after cooling to room temperature, component B was obtained.

[0028] 2.91 parts by weight of polyether polyol YEP-115 and 1.454 parts by weight of solid rubber 102 were stirred and mixed at 50°C for 25 minutes; after cooling to room temperature, component C was obtained.

[0029] Take the above-prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:96:4, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0030] Preparation Example 2: This preparation example provides a method for preparing a weather-resistant resin system suitable for molding a 66kV carbon fiber emergency repair tower, including the following steps: 50 parts by weight of bisphenol A epoxy resin and 40 parts by weight of bisphenol F epoxy resin were mixed and stirred at 60°C for 4 hours; 10 parts by weight of epoxy toughening agent were added, and the mixture was continued to be mixed and cured at 60°C for 4.5 hours; 0.1 parts by weight of silane coupling agent and 1 part by weight of release agent were added, and the mixture was stirred at 60°C for 10 minutes; the mixture was cooled to room temperature to obtain component A.

[0031] 67.2 parts by weight of methyltetrahydrophthalic anhydride, 28.8 parts by weight of methylnadic anhydride (total of 96 parts by weight of composite curing agent, with a mass ratio of 70:30) and 0.5 parts by weight of 2-ethyl-4-dimethylimidazole were stirred and mixed at 55°C for 120 minutes; after cooling to room temperature, component B was obtained.

[0032] Liquid nitrile rubber CTBN-18 was stirred and mixed at 50°C for 25 minutes; then cooled to room temperature to obtain component C.

[0033] Take the above-prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:90:4, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0034] Preparation Example 3: This preparation example provides a method for preparing a weather-resistant resin system suitable for molding a 66kV carbon fiber emergency repair tower, including the following steps: 80 parts by weight of bisphenol A epoxy resin, 10 parts by weight of bisphenol F epoxy resin and 10 parts by weight of glycidyl ether diluent containing epoxy groups were mixed and stirred at 60°C for 4 hours; 20 parts by weight of epoxy toughening agent were added and the mixture was continued to be mixed and cured at 60°C for 4.5 hours; 0.5 parts by weight of silane coupling agent and 5 parts by weight of release agent were added and stirred at 60°C for 10 minutes; the mixture was cooled to room temperature to obtain component A.

[0035] 58.8 parts by weight of methyltetrahydrophthalic anhydride, 39.2 parts by weight of methylnadic anhydride (total of 98 parts by weight of composite curing agent, with a mass ratio of 60:40) were mixed with 1.5 parts by weight of 2-ethyl-4-dimethylimidazole and 0.5 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol at 55°C for 120 minutes; after cooling to room temperature, component B was obtained.

[0036] Polyether polyol and solid rubber were mixed at a mass ratio of 4:2 and stirred at 50°C for 25 minutes; after cooling to room temperature, component C was obtained.

[0037] Take the above-prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:96:10, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0038] Examples 1-6: Example 1: This example provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method, including the following steps: 60 parts by weight of bisphenol A type epoxy resin E51, 30 parts by weight of bisphenol F type epoxy resin NPEF-170, and 5 parts by weight of epoxy Novak glycidyl ether were mixed and stirred at 60°C for 4 hours; 13 parts by weight of epoxy toughening agent WD-508 were added, and the mixture was further mixed and cured at 60°C for 4.5 hours; 0.1 parts by weight of γ-aminopropyltriethoxysilane KH550 and 1 part by weight of stearic acid release agent CLI7011 were added, and the mixture was stirred at 60°C for 10 minutes; the mixture was cooled to room temperature to obtain component A.

[0039] 48 parts by weight of methyltetrahydrophthalic anhydride, 48 parts by weight of methylnadic anhydride (total of 96 parts by weight of composite curing agent) were mixed with 0.75 parts by weight of 2-ethyl-4-dimethylimidazolium and 0.25 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol at 55°C for 120 minutes; after cooling to room temperature, component B was obtained.

[0040] Take 2.67 parts by weight of polyether polyol YEP-115 and 1.33 parts by weight of solid rubber 102 (total 4 parts by weight), stir and mix at 50°C for 25 minutes; cool to room temperature to obtain component C.

[0041] Take the above-prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:96:4, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0042] Example 2: This example provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method, including the following steps: The composition ratio and preparation process of components A and B are exactly the same as in Example 1.

[0043] The preparation of component C is as follows: Take 4 parts by weight of liquid nitrile rubber CTBN-18, stir and mix at 50°C for 25 minutes; cool to room temperature to obtain component C.

[0044] Take the prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:96:4, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0045] Example 3: This example provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method, including the following steps: The composition ratio and preparation process of components A and C are exactly the same as in Example 1.

[0046] The preparation of component B is as follows: 67.2 parts by weight of methyltetrahydrophthalic anhydride, 28.8 parts by weight of methylnadic anhydride (total of 96 parts by weight of composite curing agent, mass ratio 70:30) are mixed with 0.75 parts by weight of 2-ethyl-4-dimethylimidazole and 0.25 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol at 55°C for 120 minutes; after cooling to room temperature, component B is obtained.

[0047] Take the prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:96:4, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0048] Example 4: This example provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method, including the following steps: 50 parts by weight of bisphenol A epoxy resin and 40 parts by weight of bisphenol F epoxy resin were mixed and stirred at 60°C for 4 hours; 10 parts by weight of epoxy toughening agent were added, and the mixture was continued to be mixed and cured at 60°C for 4.5 hours; 0.1 parts by weight of silane coupling agent and 1 part by weight of release agent were added, and the mixture was stirred at 60°C for 10 minutes; the mixture was cooled to room temperature to obtain component A.

[0049] 67.2 parts by weight of methyltetrahydrophthalic anhydride, 28.8 parts by weight of methylnadic anhydride (total of 96 parts by weight of composite curing agent) and 0.5 parts by weight of 2-ethyl-4-dimethylimidazole were stirred and mixed at 55°C for 120 minutes; after cooling to room temperature, component B was obtained.

[0050] Take 4 parts by weight of liquid nitrile rubber CTBN-18 and stir and mix at 50°C for 25 minutes; cool to room temperature to obtain component C.

[0051] Take the above-prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:90:4, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0052] Example 5: This example provides a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method, including the following steps: 80 parts by weight of bisphenol A epoxy resin, 10 parts by weight of bisphenol F epoxy resin and 10 parts by weight of glycidyl ether diluent containing epoxy groups were mixed and stirred at 60°C for 4 hours; 20 parts by weight of epoxy toughening agent were added and the mixture was continued to be mixed and cured at 60°C for 4.5 hours; 0.5 parts by weight of silane coupling agent and 5 parts by weight of release agent were added and stirred at 60°C for 10 minutes; the mixture was cooled to room temperature to obtain component A.

[0053] 58.8 parts by weight of methyltetrahydrophthalic anhydride, 39.2 parts by weight of methylnadic anhydride (total of 98 parts by weight of composite curing agent) were mixed with 1.5 parts by weight of 2-ethyl-4-dimethylimidazolium and 0.5 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol at 55°C for 120 minutes; after cooling to room temperature, component B was obtained.

[0054] Take 6.67 parts by weight of polyether polyol and 3.33 parts by weight of solid rubber (total 10 parts by weight, mass ratio 4:2), mix them at 50°C for 25 minutes; cool to room temperature to obtain component C.

[0055] Take the above-prepared components separately, weigh and mix components A, B and C in a mass ratio of 100:96:10, and stir and mix at 75℃ for 25 minutes to obtain a weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers.

[0056] Example 6: This example provides a method for molding and manufacturing a 66kV carbon fiber emergency repair tower main pole, including the following steps: The weather-resistant resin system prepared in Example 1 was used as the matrix material.

[0057] T700-12K large-tow carbon fiber bundles are passed through a resin impregnation tank to fully impregnate them with the weather-resistant resin system; the resin-impregnated carbon fiber bundles are wound onto a mandrel, with the winding angle controlled by a symmetrical layup design of [87.5°, ±45°, ±10°], and the winding thickness controlled to 8mm. The wound product is placed in a curing oven and cured using a stepped curing process: 100℃ for 2 hours, 120℃ for 2 hours, and 140℃ for 2 hours. After curing, the product is demolded, trimmed, and then heat-treated at an ambient temperature of 120-140℃ for 180-200 minutes. After assembly and connection, the main pole of the 66kV carbon fiber emergency repair tower is obtained.

[0058] Comparative Examples 1-6: Comparative Example 1: Compared with Example 1, the difference is that a commercially available general-purpose two-component epoxy resin and amine curing agent system is used instead of the three-component resin system of the present invention, while all other application conditions are the same.

[0059] Comparative Example 2: Compared with Example 1, the difference is that the composite curing agent in component B uses only 96 parts by weight of single methyltetrahydrophthalic anhydride, without the addition of methylnadic anhydride, while the rest are the same.

[0060] Comparative Example 3: Compared with Example 1, the difference is that component C was removed from the design. The final resin system is made by mixing components A and B in a mass ratio of 100:96, and everything else is the same.

[0061] Comparative Example 4: Compared with Example 1, the difference is that 5 parts by weight of a common inactive diluent (such as xylene) was used to replace the epoxy Novak glycidyl ether with an active epoxy group in component A, and all other components were the same.

[0062] Comparative Example 5: Compared with Example 1, the difference is that only 1 part by weight of a single accelerator (2-ethyl-4-dimethylimidazole) was used in component B, and 2,4,6-tris(dimethylaminomethyl)phenol was not added, while the rest were the same.

[0063] Comparative Example 6: Compared with Example 1, the difference is that the three-component separation process design was not adopted. Instead, the traditional one-pot mixing method was used, in which all the raw materials of components A, B and C were mixed and prepared at room temperature in one go. The amount of other components and the subsequent curing conditions were the same.

[0064] Test Examples 1-5: Test Example 1: Curing Kinetics and Process Performance Test 50g of sample was extracted from the resin system after mixing in Examples 1 to 5 and injected into a standard aluminum test dish.

[0065] The aluminum test dish was placed in a constant temperature water bath set to 25°C for temperature adjustment. After the sample temperature stabilized, the initial viscosity of the sample was measured using an NDJ-8S rotational viscometer. The ambient temperature was then kept constant, and the viscosity was measured every 30 minutes. The time taken for the viscosity to rise to twice the initial viscosity was recorded and marked as the 25°C service life.

[0066] Turn on the gel time measuring instrument with thermocouple temperature control, and precisely set and keep the surface temperature of the test hot stage at 130°C.

[0067] Using a microdropper, 0.5g of resin sample was dropped onto the center of the 130°C test stage, and a timer was started simultaneously. A stainless steel needle was used to continuously pick up the resin strands on the surface of the liquid resin. Timing was stopped when the resin strands pulled out by the needle broke and the resin transitioned from a liquid to a non-flowing elastic gel state; this time was recorded as the gel time at 130°C. Samples exhibiting significant bubble interference were discarded during the test. Each example was repeated three times, and the arithmetic mean was recorded.

[0068] Test results: Table 1. Curing kinetics and process performance test data of the resin system in the examples Results analysis: According to the data in Table 1, the resin systems of Examples 1 to 5 all exhibited a pot life of over 3.5 hours at room temperature, while the gel time was controlled within 1 minute at a high temperature of 130°C. At room temperature, the accelerator composed of 2-ethyl-4-dimethylimidazole and 2,4,6-tris(dimethylaminomethyl)phenol exhibited catalytic inhibition. The chemical structure and steric hindrance of the dual accelerators delayed the initial complex formation rate, demonstrating a latent characteristic. During this stage, the ring-opening esterification reaction of the epoxy group and the anhydride was greatly limited, macroscopically manifested as a slow viscosity increase, providing the operating time window required for carbon fiber impregnation and winding molding.

[0069] When the ambient temperature jumped to 130°C, thermodynamic conditions triggered the rapid dissociation of the dual accelerators. 2-Ethyl-4-dimethylimidazolium and 2,4,6-tris(dimethylaminomethyl)phenol exhibited a synergistic catalytic effect at high temperatures, altering the activation energy pathway of the reaction. The highly reactive methyltetrahydrophthalic anhydride rapidly initiated the first stage of the crosslinking reaction, causing the liquid resin to complete its phase transition and reach its gel point within 38 to 56 seconds. Subsequently, methylnadic anhydride participated in building a dense network. In Example 4, due to the absence of glycidyl ether diluents, the initial viscosity increased to 3824 mPa·s, and the high concentration of reactive groups accelerated exothermic accumulation, shortening the pot life to 3.75 hours. In Example 5, the amounts of diluent and accelerator were increased, reducing the initial viscosity to 964 mPa·s, while the high-temperature gel time was shortened to 38.6 seconds. Despite altering the micro-crosslinking density, the formulation variables did not disrupt the heat-sensitive mechanism provided by the dual accelerators; the system maintained a kinetic balance between a long pot life at room temperature and rapid gelation at low temperatures. The three-component separation process isolates and stores the resin, curing agent, and additives, avoiding spontaneous initiation of highly active ingredients during the mixing stage, and providing fundamental support for the stability of test data at the material preparation level.

[0070] Test results: Table 2. Test data on heat resistance and interface properties of resin castings and composite material components from the examples. Results analysis: According to the data in Table 2, the glass transition temperatures of the resin matrices prepared in Examples 1 to 5 range from 121.3℃ to 135.2℃, and the corresponding interlaminar shear strengths of the carbon fiber composite samples range from 62.4MPa to 76.8MPa.

[0071] The differences in thermodynamic data are determined by the microstructure of the three-dimensional cross-linked network after curing. In the system, methyltetrahydrophthalic anhydride and methylnadic anhydride, which has higher steric hindrance, jointly construct a composite anhydride cross-linked network. The bridged ring skeleton within the methylnadic anhydride molecule increases the rigidity of the network structure, restricting the slippage of macromolecular chain segments at high temperatures. In Example 3, the adjustment of the curing agent ratio changed the rigidity composition of the network, and the highest glass transition temperature of 135.2℃ was measured. In Example 5, the amount of the first toughening agent was increased to 20 parts by weight, and a large number of flexible long chain segments were directly embedded into the main network through chemical bonds, increasing the free volume of the internal structure, resulting in a relative decrease in cross-linking density and a decline in macroscopic heat resistance, with the test value dropping to 121.3℃.

[0072] The shear strength of the composite short beam directly reflects the interfacial bonding quality between the resin matrix and the reinforcing fiber. The γ-aminopropyltriethoxysilane coupling agent introduced into the system participates in the construction of the chemical interface. The amino group at one end of the coupling agent undergoes ring-opening addition with the epoxy group in the resin matrix, while the siloxane group at the other end undergoes condensation reaction with the polar hydroxyl groups present on the carbon fiber surface after hydrolysis. This covalent bond formation creates a stress transfer gradient layer between the inorganic fiber and the organic resin. Simultaneously, rheological properties determine the physical wetting effect. In Example 4, no glycidyl ether diluent was added, resulting in a higher initial viscosity of the resin system. This increased capillary flow resistance as the liquid resin penetrated into the gaps between the large-tow carbon fiber monofilaments, restricting the venting process. The physical micropores remaining at the interface became stress concentration points under load, inducing microcracks and causing the interlaminar shear strength of the sample to decrease to 62.4 MPa. In Example 1, the viscosity state, combined with the coupling agent, achieved a balance between physical wetting and chemical bonding, resulting in a maximum interlaminar shear strength of 76.8 MPa. Test results under various variables confirm that the material system can cope with the risks of foundation thermal stress and interlayer shear failure faced by the emergency repair tower.

[0073] Test Example 3: Comparative Test of Macroscopic Impact Toughness and Mechanical Strength The resin systems prepared in Example 1, Comparative Examples 1, 2, and 3 were degassed in a vacuum chamber at a pressure of -0.09 MPa for 20 minutes. The resin liquid was then poured into polytetrafluoroethylene molds coated with a release agent and cured in stages at 100°C / 2h, 120°C / 2h, and 140°C / 2h.

[0074] After the samples cooled to room temperature, they were demolded. The cured material was then cut into standard samples using a CNC machining center: tensile samples were machined into a type 1B dumbbell shape with a thickness of 4 mm; bending and unnotched impact samples were machined into long strips measuring 80 mm in length, 10 mm in width, and 4 mm in thickness. After machining, the sides of the samples were sanded with fine sandpaper to remove machining marks.

[0075] A dumbbell-shaped specimen was subjected to tensile testing using an electronic universal testing machine. The clamp separation speed was set to 2.0 mm / min, and the maximum tensile stress at the time of specimen fracture was recorded as the tensile strength.

[0076] On the same universal testing machine, replace the three-point bending fixture, set the span to 64 mm, set the loading head descent speed to 2.0 mm / min, apply the load until the specimen breaks, and record the bending strength.

[0077] Impact tests were conducted on unnotched strip specimens using a simply supported beam impact testing machine. A pendulum with an energy of 2J was selected. The specimen was placed flat on a support with a span of 62mm, and the pendulum was released to impact the middle of the specimen. The unnotched impact strength was read and calculated. Each set of mechanical tests was repeated 5 times, and the arithmetic mean was taken.

[0078] Test results: Table 3. Test data of mechanical strength and impact toughness of the cured resins of the examples and comparative examples. Results analysis: According to the data in Table 3, the comprehensive mechanical properties of Example 1 are at the highest level. Comparative Example 1 uses a commercially available two-component amine-based curing system, and its tensile strength and impact strength are at a basic level, indicating that conventional resin networks cannot directly meet the mechanical requirements of dynamic alternating load conditions. Comparative Example 2 uses a single methyltetrahydrophthalic anhydride curing system. Due to the lack of a composite network constructed with methylnadic anhydride, the rigidity-flexibility balance of the matrix crosslinking structure is shifted, resulting in a decrease in flexural strength to 114.8 MPa and an impact strength degradation to 24.5 kJ / m², confirming the intervention role of bridged ring structure anhydrides in the stress transfer and deformation coordination of the main chain segment.

[0079] Comparative Example 3, which removed the polyether polyol and solid rubber components, showed slight fluctuations in tensile strength, but its unnotched impact strength plummeted to 18.4 kJ / m², less than half of the value in Example 1. Example 1 achieved an impact toughness of 38.6 kJ / m², an improvement attributed to the dual toughening mechanism built within the system. During the curing stage, the epoxy toughening agent in component A chemically bonds into the three-dimensional matrix, increasing the internal free volume and releasing stress at the molecular level. With increasing curing depth, the increased molecular weight triggers thermodynamic incompatibility, causing microphase separation between the polyether polyol and rubber in component C within the matrix. This results in the aggregation of a microscale dispersed phase within the continuous epoxy matrix, forming an island structure. When the sample is subjected to a high-speed impact load from a pendulum, the stress field concentrates and redistributes at the phase interfaces of these rubber particles. The dispersed phase induces numerous crazes in the matrix and promotes localized shear yielding of the resin matrix surrounding the particles. The initiation, branching, and plastic deformation of the shear bands absorb and consume the energy required for crack propagation. Comparative Example 3 lacks this phase-state energy dissipation mechanism and relies solely on the limited deformation of the cross-linked network itself, exhibiting typical brittle fracture characteristics under impact loads. The synergistic effect of molecular-level flexible blocks and phase-state island microparticles resolves the physical contradiction between high matrix strength and high impact brittleness.

[0080] Test Example 4: Comparative Test of Aging and Weather Resistance in Harsh Environments Resin systems were prepared according to Example 1, Comparative Example 1, and Comparative Example 4, and cast and processed into Type 1B standard tensile specimens. Eighty specimens were prepared for each formulation and randomly divided into four groups for determining the initial tensile strength and the tensile strength after UV aging, damp heat aging, and salt spray aging.

[0081] The first group of samples was placed in an accelerated UV aging chamber using UVA-340 lamps, with an irradiance set to 0.76 W / m². The test cycle was set to 8 hours of illumination (black panel temperature 60°C) and 4 hours of condensation (black panel temperature 50°C), and the samples were removed after 500 hours of continuous operation.

[0082] The second group of samples was placed in a constant temperature and humidity test chamber with environmental parameters set at 85°C and 85% relative humidity, and then removed after continuous exposure for 720 hours (30 days).

[0083] The third group of samples was placed in a neutral salt spray test chamber and continuously sprayed with a 5% sodium chloride solution. The temperature of the test chamber was maintained at 35℃, and the salt spray deposition rate was controlled at 1.5 mL / (80 cm²·h). The samples were taken out after 720 hours (30 days) of continuous testing.

[0084] The samples treated with the three aging environments were cleaned of surface residues with deionized water, dried, and conditioned for 48 hours in a standard environment of 23°C and 50% relative humidity. The tensile breaking strength of each group of samples was determined using an electronic universal testing machine at a tensile speed of 2.0 mm / min. The arithmetic mean was calculated, and the strength retention rate was calculated by comparing it with the initial tensile strength of the unaged samples.

[0085] Test results: Table 4. Harsh environmental aging and weathering performance test data of the examples and comparative examples Results analysis: According to the data in Table 4, after three accelerated aging tests, Example 1 maintained a tensile strength retention rate of over 89%, and its overall weather resistance was far superior to that of the conventional commercially available two-component system, Comparative Example 1. The damage to polymer materials caused by environmental media mainly stems from the hydrolysis of chemical bonds, photo-oxidative degradation, and the migration and aggregation of small molecules. The basic epoxy resin and amine-cured network structure used in Comparative Example 1 were relatively simple. Under high temperature, high humidity, and ultraviolet excitation, the crosslinked network nodes were prone to breakage, resulting in a significant drop in tensile strength to 38.6 MPa after damp heat aging.

[0086] Example 1: The matrix is ​​composed of a blend of bisphenol A and bisphenol F epoxy resins. The low viscosity of the bisphenol F structure improves the reaction kinetics of the crosslinking process and increases the crosslinking density after curing. The three-dimensional network constructed with composite anhydrides further hinders the penetration and diffusion of water molecules, reducing the probability of ester bond hydrolysis.

[0087] Comparative Example 4 used a non-reactive diluent instead of the glycidyl ether diluent in this scheme, and its initial tensile strength was 82.4 MPa, similar to that of Example 1. However, under aging conditions, its strength retention rate significantly declined, with the damp heat aging retention rate dropping to 74.3%. The non-reactive diluent molecules lack functional groups that participate in esterification or etherification reactions, existing in a free state within the free volume of the crosslinked network. Driven by long-term thermal stress and moisture gradients, these free small molecules migrate and volatilize outwards. This physical process leaves microscopic pores and interface defects within the matrix, disrupting the network continuity. These pores provide diffusion channels for the deep penetration of moisture, oxygen, and salt spray ions, leading to internal stress concentration and matrix plasticization. The glycidyl ether diluent used in Example 1 contains active epoxy groups, participating in ring-opening crosslinking as a comonomer during the high-temperature curing stage, becoming part of the three-dimensional network in the form of covalent bonds. The anchoring effect of chemical bonds fundamentally cuts off the migration path of diluent molecules, inhibits the micro-defect generation mechanism caused by them, and ensures the long-term structural stability of materials under the influence of complex physicochemical fields.

[0088] Test Example 5: Comparison of the effects of preset components and mixing process on the pot life Resin solutions were prepared according to the formulation requirements of Example 1, Comparative Example 5, and Comparative Example 6, respectively. For Comparative Example 6, the epoxy resin, diluent, toughening agent, composite anhydride curing agent, accelerator, silane coupling agent, and release agent were added to a container at 25°C and mechanically stirred.

[0089] Extract 50g of sample from each of the three prepared adhesive solutions and inject them into labeled aluminum test dishes. Place the test dishes in a constant temperature water bath at 25℃.

[0090] After the sample temperature equilibrates with the water bath temperature, the initial viscosity of each sample is tested using a rotational viscometer. Subsequently, while maintaining a constant ambient temperature and testing conditions, the viscosity of the adhesive is continuously measured at 30-minute intervals. The time taken for the system viscosity to rise to twice the initial viscosity value is recorded, and this time is recorded as the 25°C pot life.

[0091] A 0.5g sample is dropped onto a gel testing platform maintained at 130℃. A metal needle is used to continuously pick up strands from the surface of the resin, recording the time from sample contact with the platform until the resin loses its fluidity and the strand breaks; this time is taken as the gel time at 130℃. Each test is repeated three times, and the arithmetic mean is taken.

[0092] Test results: Table 5. Test data on the impact of preset components and mixing process on the pot life of the examples and comparative examples. Results analysis: According to the data in Table 5, Comparative Example 5 used a single 2-ethyl-4-dimethylimidazole as a promoter, resulting in a decrease in the system's pot life at 25°C to 1.83 hours and an increase in the gel time at 130°C to 134.5 seconds. Single imidazole compounds possess catalytic activity for curing acid anhydrides at room temperature, lacking a latent mechanism, allowing the ring-opening esterification reaction between the epoxy groups and the acid anhydride to proceed spontaneously at room temperature. The accumulation of large molecular weights in the system leads to a rapid increase in viscosity beyond the pot life critical point. When the ambient temperature reaches the high-temperature curing stage of 130°C, the catalytic efficiency of the single catalyst is limited, the exothermic reaction rate slows down, and rapid gelation cannot be achieved. Example 1 incorporated 2,4,6-tris(dimethylaminomethyl)phenol to form a dual-promoter system. Under room temperature conditions, the two form a pre-defined complex. The steric hindrance within the structure masks the catalytically active center, inhibiting the initiation of the cross-linking reaction from a chemothermodynamic perspective. When subjected to thermal excitation at 130°C, the complex rapidly dissociates and generates dual catalytic activity, synergistically altering the activation energy pathway of the curing reaction and forming a rapid cross-linking network.

[0093] Comparative Example 6 employed a one-pot mixing process, achieving an initial viscosity of 2845 mPa·s and a pot life decay to 1.15 hours. In the multi-component coexistence state, the γ-aminopropyltriethoxysilane coupling agent added to the formulation exhibited different reactivity at both ends; the primary amine in its structure could undergo a ring-opening addition reaction with the epoxy resin at room temperature. The active groups in the first toughening agent also exhibited competitive reactions. Disordered pre-crosslinking polymerization occurred within the system, and the premature formation of the micro-gel phase increased the molecular chain slip resistance, reflected in the rheological properties as a significant increase in initial viscosity and a closed pot life window. The three-component separation process used in Example 1 physically isolated the main resin, composite anhydride, and various active additives during storage, preventing unnecessary side reaction losses. After mixing during the formulation stage, the system maintained a low viscosity, ensuring capillary penetration during impregnation of large-tow carbon fibers.

Claims

1. A weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers, characterized in that, It is prepared by mixing components A, B and C in a mass ratio of 100:(90-105):(4-10); Component A is made from the following raw materials in parts by weight: 50-80 parts of bisphenol A type epoxy resin; 10-40 parts of bisphenol F type epoxy resin; 5-15 parts of glycidyl ether diluent containing epoxy groups; 10-20 parts of epoxy first toughening agent; 0.1-0.5 parts of silane coupling agent; and 1-5 parts of release agent. Component B is made from raw materials comprising the following parts by weight: 50-70 parts of methyltetrahydrophthalic anhydride; 30-50 parts of methylnadic anhydride; 0.5-1.5 parts of 2-ethyl-4-dimethylimidazole; and 0.2-0.5 parts of 2,4,6-tris(dimethylaminomethyl)phenol. Component C is made from raw materials comprising the following parts by weight: 4-10 parts of a second toughening agent.

2. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers according to claim 1, characterized in that, In component A, the glycidyl ether diluent containing epoxy groups is epoxynovac glycidyl ether, and the silane coupling agent is γ-aminopropyltriethoxysilane.

3. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method according to claim 1, characterized in that, In component C, the second toughening agent is liquid nitrile rubber, or a compound of polyether polyol and solid rubber mixed in a mass ratio of (4-6):(2-4).

4. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method according to claim 1, characterized in that, In component A, the mass ratio of the bisphenol A type epoxy resin to the bisphenol F type epoxy resin is (50-60):(30-40). Preferably, the mass ratio of component A, component B and component C is 100:96:

4.

5. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers according to claim 1, characterized in that, In component B, the mass ratio of methyltetrahydrophthalic anhydride to methylnadic anhydride is (60-70):(30-40). The mass ratio of 2-ethyl-4-dimethylimidazole to 2,4,6-tris(dimethylaminomethyl)phenol is (3-4):

1.

6. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers according to claim 1, characterized in that, In component A, the release agent is a stearic acid-based internal release agent.

7. A method for preparing a weather-resistant resin system suitable for molding a 66kV carbon fiber emergency repair tower, used to prepare the weather-resistant resin system suitable for molding a 66kV carbon fiber emergency repair tower as described in any one of claims 1-6, characterized in that, Includes the following steps: Bisphenol A type epoxy resin, bisphenol F type epoxy resin and glycidyl ether diluent containing epoxy groups are mixed and stirred, then epoxy first toughening agent is added and mixed and cured, and finally silane coupling agent and mold release agent are added and mixed and stirred. After cooling, component A is obtained. Methyltetrahydrophthalic anhydride, methylnadic anhydride, 2-ethyl-4-dimethylimidazolium and 2,4,6-tris(dimethylaminomethyl)phenol were mixed and stirred, and then cooled to obtain component B; The second toughening agent was stirred at a constant temperature and then cooled to obtain component C; Take the prepared components separately and mix them evenly according to the corresponding mass ratio to obtain the weather-resistant resin system.

8. The method for preparing a weather-resistant resin system suitable for molding a 66kV carbon fiber emergency repair tower according to claim 7, characterized in that, In the step of preparing component A, the bisphenol A type epoxy resin, the bisphenol F type epoxy resin and the glycidyl ether diluent are mixed and stirred at 60-70°C for 3-5 hours in advance. After adding the epoxy-based first toughening agent, continue to mix and mature at a constant temperature of 60-70°C for 4-5 hours; Finally, add the silane coupling agent and the release agent, and stir at 60-70°C for 10-20 minutes.

9. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method according to claim 7, characterized in that, In the step of preparing component B, the reaction temperature is controlled at 50-60℃ and the stirring time is 100-150 minutes; In the step of preparing component C, the stirring temperature is controlled at 45-55℃ and the stirring time is 20-30 minutes.

10. The weather-resistant resin system suitable for molding 66kV carbon fiber emergency repair towers and its preparation method according to claim 7, characterized in that, The specific steps for mixing all components evenly are as follows: After weighing and mixing components A, B, and C, the mixture is stirred at a constant temperature of 70-80°C for 20-30 minutes.

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