Anti-aging electrical epoxy resin and preparation method therefor

Abstract

The present invention belongs to the technical field of electrical epoxy resin materials, and particularly relates to an anti-aging electrical epoxy resin and a preparation method therefor. The epoxy resin is composed of the following raw materials in parts by weight: 70-80 parts of an epoxy resin, 3-5 parts of modified nano silicon dioxide, 1-3 parts of aminated graphene, 5-8 parts of polyurethane, 0.5-1 part of methyltriethoxysilane, 0.1-0.5 parts of sodium lauryl sulfate, 0.5-1 part of an antioxidant, and 0.5-1 part of an ultraviolet absorbent. In the present invention, by means of silane-modified nano silicon dioxide and aminated graphene, the aging resistance and corrosion resistance of the epoxy resin are improved. The nano silicon dioxide enhances the hardness and rigidity, while the aminated graphene improves the toughness and thermal conductivity. The synergistic effect of the two components results in multiple physical barriers, reducing the penetration of aging factors and corrosive media. Furthermore, the surface is subjected to a hydrophobic treatment using methyltriethoxysilane to further improve the weather resistance and moisture resistance.

Description

An anti-aging electrical epoxy resin and its preparation method Technical Field

[0001] This invention belongs to the technical field of electrical epoxy resin materials, specifically relating to an anti-aging electrical epoxy resin and its preparation method. Background Technology

[0002] Anti-aging epoxy resins have wide applications in electronics, electrical engineering, and high-voltage insulation. They are mainly used to manufacture electronic packaging materials, electrical insulation materials, and coatings to protect electronic components from environmental damage and extend equipment lifespan. Epoxy resins possess excellent mechanical properties, chemical resistance, good electrical insulation, and adhesive properties, thus making them widely used in electronic and electrical equipment. However, epoxy resins have disadvantages such as high brittleness, poor impact resistance, and susceptibility to aging when exposed to high temperatures, ultraviolet radiation, and humid environments for extended periods. These issues affect their durability and stability in electrical applications. Traditional epoxy resins are prone to thermal degradation at high temperatures, leading to a decline in mechanical and electrical properties; ultraviolet radiation and moisture cause chemical aging, causing them to lose their original properties; under long-term stress, epoxy resins are prone to fatigue cracks, affecting their service life; under the influence of oxygen and free radicals, epoxy resins undergo oxidative degradation, leading to material performance degradation; and certain chemicals (such as acids, alkalis, and solvents) can corrode epoxy resins, affecting their long-term stability. Furthermore, epoxy resin aging mainly includes two forms: physical aging and chemical aging. Physical aging is primarily manifested as brittleness, cracking, and decreased mechanical properties. This is usually due to factors such as temperature changes and stress during use. Chemical aging is primarily manifested as degradation, reduced crosslinking density, and performance decline. This is usually due to environmental factors such as oxygen, ultraviolet radiation, and moisture during use. After aging, the mechanical strength, electrical properties, and corrosion resistance of the resin will significantly decrease, easily leading to insulation failure and other problems in equipment, thus seriously affecting the safety and service life of the system. Therefore, based on the above problems, it is extremely necessary to develop an electrical epoxy resin that can effectively resist aging and corrosion. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this invention is to provide an anti-aging electrical epoxy resin and its preparation method.

[0004] The technical effects described in this invention are achieved through the following technical solution: an anti-aging electrical epoxy resin, comprising the following raw materials in parts by weight: 70-80 parts epoxy resin, 3-5 parts modified nano silica, 1-3 parts aminated graphene, 5-8 parts polyurethane, 0.5-1 part methyltriethoxysilane, 0.1-0.5 parts sodium dodecyl sulfate, 0.5-1 part antioxidant, and 0.5-1 part ultraviolet absorber.

[0005] Preferably, the epoxy resin is a bisphenol A type epoxy resin.

[0006] Preferably, the antioxidant is any one of 2,6-di-tert-butyl-p-cresol, ascorbic acid, N-phenyl-α-naphthylamine, and dilauryl thiodipropionate.

[0007] Preferably, the ultraviolet absorber is any one of 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, benzyl salicylate, and phenyl salicylic acid.

[0008] Preferably, the specific preparation steps of the modified nano-silica are as follows:

[0009] A1: Add nano-silica to anhydrous ethanol and ultrasonically disperse it at 100-200W for 30-60 min to obtain a nano-silica dispersion; add γ-glycidoxypropyltrimethoxysilane to anhydrous ethanol, stir and mix evenly, then slowly add deionized water and acetic acid, and stir the reaction at 200-300 rpm for 10-30 min to obtain a coupling agent solution;

[0010] A2: Slowly add the coupling agent solution prepared in step A1 to the nano silica dispersion prepared in step A1, stir at 300-500 rpm for 12 h at room temperature, centrifuge, wash repeatedly with deionized water 5 times, and vacuum dry at 60-80℃ for 12-24 h to obtain modified nano silica.

[0011] Preferably, in step A1, the ratio of the amount of nano-silica to anhydrous ethanol is 1g:40-50mL; the ratio of the amount of γ-glycidyl etheroxypropyltrimethoxysilane, anhydrous ethanol, deionized water and acetic acid is 1g:15-20mL:0.5-0.6mL:0.04-0.05mL.

[0012] Preferably, in step A2, the volume ratio of the coupling agent solution to the nano-silica dispersion is 0.02 to 0.03:1.

[0013] Preferably, the specific preparation steps of the amino-based graphene are as follows:

[0014] B1: Add graphite powder to a flask, slowly add concentrated sulfuric acid and concentrated phosphoric acid, control the temperature at 0-5℃, stir and disperse evenly, raise the temperature to 10℃, then slowly add potassium permanganate. After the addition is complete, raise the temperature to 35-40℃, stir and react for 12-24 hours, then slowly add deionized water to dilute, then add hydrogen peroxide, centrifuge, wash three times with deionized water and 1M HCl solution, and vacuum dry at 60℃ for 12-24 hours to obtain graphene oxide;

[0015] B2: Disperse the graphene oxide prepared in step B1 in dimethyl sulfoxide and ultrasonically disperse it at 100-150W for 30-60 min to obtain a graphene oxide dispersion; control the temperature at 0-5℃ and slowly add 3-aminopropyltriethoxysilane to the graphene oxide dispersion. After the addition is complete, raise the temperature to 60℃ and stir continuously for 12-24 h. Centrifuge, wash three times with deionized water and ethanol, and vacuum dry at 60℃ for 12-24 h to obtain aminographene.

[0016] Preferably, in step B1, the ratio of the amount of graphite powder, concentrated sulfuric acid and concentrated phosphoric acid is 1g:20-25mL:2-3mL; and the ratio of the amount of potassium permanganate, deionized water, hydrogen peroxide and graphite powder is 3g:80-100mL:3-4mL:1g.

[0017] Preferably, in step B2, the ratio of the amount of graphene oxide, dimethyl sulfoxide and 3-aminopropyltriethoxysilane is 3-5 mg: 1 mL: 0.04-0.05 mL.

[0018] Preferably, another aspect of the present invention provides a method for preparing an anti-aging electrical epoxy resin, the specific preparation steps of which are as follows:

[0019] S1: Modified nano-silica and amino graphene are added to epoxy resin in a weight ratio and stirred at 1000-1500 rpm for 40-60 min. After being evenly dispersed, sodium dodecyl sulfate is added and stirred at 800-1200 rpm for 15-30 min. Then, polyurethane, antioxidant and ultraviolet absorber are added and stirred at 500-800 rpm for 15-30 min to obtain mixed raw materials.

[0020] S2: The mixed raw materials prepared in step S1 are cured at 80°C for 2 hours, and then cured at 120°C for 2 hours to obtain a cured material; methyltriethoxysilane is added to 100 parts by weight of anhydrous ethanol, and half the weight of the substrate is added to deionized water. The mixture is stirred at 300-500 rpm for 15-30 minutes to obtain a hydrolysis solution.

[0021] S3: Spray the hydrolysis solution prepared in step S2 onto the surface of the cured material prepared in step S2. After spraying, vacuum dry at 60-80℃ for 1-2 hours to obtain epoxy resin.

[0022] Preferably, in step S3, the spraying operation parameters are 0.1-0.3 MPa, distance 15-20 cm, speed 20-30 cm / s, and the spraying is allowed to stand for 5-10 minutes after each spraying, for a total of 3 sprayings.

[0023] The beneficial effects of this invention are as follows:

[0024] This invention significantly improves the anti-aging and corrosion resistance of epoxy resin matrices by introducing silane-modified nano-silica and amino-based graphene. Nano-silica, due to its high specific surface area and surface energy, easily aggregates in epoxy resin matrices, leading to uneven dispersion. Surface modification with a silane coupling agent (γ-glycidoxypropyltrimethoxysilane) introduces epoxy groups and other organic functional groups onto the surface of nano-silica, transforming its surface from hydrophilic to organophilic, significantly improving its dispersibility and compatibility in epoxy resins. One end of the silane coupling agent (siloxane group) hydrolyzes to generate silanol, which undergoes a dehydration condensation reaction with the hydroxyl groups on the surface of nano-silica, forming a stable Si-O-Si covalent bond. The epoxy group at the other end can react with the active groups in the epoxy resin matrix, further achieving cross-linking. Through this dual-functional structure, nano-silica can not only be firmly bonded to the matrix, but also significantly enhance the interfacial bonding force between the filler and the matrix, reduce interfacial defects and stress concentration, thereby improving the mechanical properties and aging resistance of epoxy resin.

[0025] This invention utilizes amination modification to enhance the affinity of graphene surface for epoxy resin. Amino groups can chemically react with epoxy groups to form stable covalent bonds, improving the dispersibility and compatibility of graphene in epoxy resin, strengthening interfacial bonding, reducing interfacial defects, and improving stress transfer efficiency. Furthermore, the high thermal and electrical conductivity of graphene itself forms an effective heat-conducting network within the matrix, significantly improving the material's heat dissipation performance and preventing material aging caused by high temperatures. Simultaneously, the layered structure of graphene forms a physical barrier, delaying the penetration of oxygen, moisture, and corrosive media, while amination further enhances this barrier effect, resulting in a longer service life for the material in corrosive environments. Silane-modified nano-silica and amination-modified graphene are uniformly dispersed in the epoxy resin matrix, forming multiple physical barriers that synergistically slow down the penetration of aging factors and corrosive media. Nano-silica enhances the hardness and rigidity of the material, while amino-based graphene improves its toughness and thermal conductivity. Their synergistic effect gives the material high strength, high toughness, and excellent thermal stability, further enhancing its durability in electrical application environments. Simultaneously, these additives effectively reduce oxygen and UV penetration, slowing the consumption rate of antioxidants and UV absorbers, thus making the chemical protection within the material more durable. Modified nano-silica forms strong chemical bonds with the matrix through silane coupling agents, while amino-based graphene forms additional hydrogen bonds between the amino groups and both the matrix and nano-silica. This multi-interfacial bonding mechanism significantly improves the compatibility between the nanofiller and the matrix, reducing interfacial defects.

[0026] This invention employs a hydrophobic treatment of the material surface with methyltriethoxysilane (MTES). The silanol groups generated through hydrolysis form Si-O-Si bonds, self-assembling to form a uniform hydrophobic coating. The unreacted silanol groups of the MTES coating can form a well-compatible interface with the glycidyl ether groups of modified nano-silica, while the amino groups of aminated graphene can also react with the silanol groups in the coating to form stable chemical bonds. This achieves a good combination among the three, further improving the dispersion and compatibility of the filler in the matrix and effectively preventing material performance degradation due to poor interfaces. This silane-based hydrophobic coating not only effectively delays the penetration of moisture and corrosive media but also adheres to the epoxy resin surface through physical adsorption and hydrogen bonding, further improving the overall material's weather resistance and moisture resistance. The outer hydrophobic treatment blocks the entry of moisture and corrosive substances, while the inner nanofiller further slows the diffusion of residual permeates. The combined effect of the inner and outer layers significantly improves the material's corrosion resistance. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 shows the change in tensile strength of the epoxy resins prepared in Example 2 and Comparative Examples 1-4 under ultraviolet aging test.

[0029] Figure 2 is a thermal deformation temperature diagram of the epoxy resins prepared in Example 2 and Comparative Examples 1-4 of the present invention;

[0030] Figure 3 shows the change in tensile strength of the epoxy resins prepared in Example 2 and Comparative Examples 1-4 of this invention under corrosion resistance testing. Detailed Implementation

[0031] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be noted that, unless otherwise specified, the raw materials involved in the present invention are all purchased through conventional commercial channels.

[0032] Example 1: An anti-aging electrical epoxy resin, comprising the following raw materials in parts by weight: 70 parts epoxy resin, 3 parts modified nano silica, 1 part aminated graphene, 5 parts polyurethane, 0.5 parts methyltriethoxysilane, 0.1 parts sodium dodecyl sulfate, 0.5 parts antioxidant and 0.5 parts ultraviolet absorber.

[0033] The specific preparation steps for modified nano-silica are as follows:

[0034] A1: Add 10g of nano-silica to 400mL of anhydrous ethanol and sonicate at 100W for 60min to obtain a nano-silica dispersion; add 10g of γ-glycidoxypropyltrimethoxysilane to 150mL of anhydrous ethanol and stir to mix evenly, then slowly add 5mL of deionized water and 0.4mL of acetic acid, and stir at 200rpm for 30min to obtain a coupling agent solution;

[0035] A2: Slowly add 16 mL of coupling agent solution prepared in step A1 to 400 mL of nano silica dispersion prepared in step A1. Stir at 300 rpm for 12 h at room temperature, centrifuge, wash 5 times with deionized water, and vacuum dry at 60℃ for 24 h to obtain modified nano silica.

[0036] The specific preparation steps for amino-based graphene are as follows:

[0037] B1: Add 10g of graphite powder to a flask, slowly add 200mL of concentrated sulfuric acid and 20mL of concentrated phosphoric acid, control the temperature at 5℃, stir and disperse evenly, raise the temperature to 10℃, then slowly add 30g of potassium permanganate. After the addition is complete, raise the temperature to 35℃, stir and react for 24h, then slowly add 800mL of deionized water to dilute, then add 30mL of hydrogen peroxide, centrifuge, wash three times with deionized water and 1M HCl solution, and vacuum dry at 60℃ for 12h to obtain graphene oxide;

[0038] B2: Disperse 900 mg of graphene oxide prepared in step B1 in 300 mL of dimethyl sulfoxide and sonicate at 100 W for 60 min to obtain a graphene oxide dispersion; control the temperature at 5 °C and slowly add 12 mL of 3-aminopropyltriethoxysilane to the graphene oxide dispersion. After the addition is complete, raise the temperature to 60 °C and stir continuously for 12 h. Centrifuge, wash three times with deionized water and ethanol, and vacuum dry at 60 °C for 12 h to obtain aminographene.

[0039] The specific preparation steps of the anti-aging electrical epoxy resin are as follows:

[0040] S1: Modified nano-silica and amino graphene were added to bisphenol A type epoxy resin in a certain weight ratio, stirred at 1000 rpm for 60 min, and after being evenly dispersed, sodium dodecyl sulfate was added and stirred at 800 rpm for 30 min. Then, polyurethane, 2,6-di-tert-butyl-p-cresol and 2-hydroxy-4-methoxybenzophenone were added and stirred at 500 rpm for 30 min to obtain mixed raw materials.

[0041] S2: The mixed raw material prepared in step S1 is cured at 80°C for 2 hours, and then cured at 120°C for 2 hours to obtain a cured material; methyltriethoxysilane is added to 100 parts by weight of anhydrous ethanol, and half the weight of the substrate is added to deionized water. The mixture is stirred at 300 rpm for 30 minutes to obtain a hydrolysis solution.

[0042] S3: Spray the hydrolysis solution prepared in step S2 onto the surface of the cured material prepared in step S2. The spraying operation parameters are 0.1 MPa, distance 15 cm, speed 20 cm / s, and let stand for 5 min after each spraying. Spray for a total of 3 times. After spraying, vacuum dry at 60℃ for 2 h to obtain epoxy resin.

[0043] Example 2: An anti-aging electrical epoxy resin, comprising the following raw materials in parts by weight: 80 parts epoxy resin, 5 parts modified nano silica, 3 parts aminated graphene, 8 parts polyurethane, 1 part methyltriethoxysilane, 0.5 parts sodium dodecyl sulfate, 1 part antioxidant and 1 part ultraviolet absorber.

[0044] The specific preparation steps for modified nano-silica are as follows:

[0045] A1: Add 10g of nano-silica to 500mL of anhydrous ethanol and sonicate at 200W for 40min to obtain a nano-silica dispersion; add 10g of γ-glycidoxypropyltrimethoxysilane to 200mL of anhydrous ethanol, stir and mix evenly, then slowly add 6mL of deionized water and 0.5mL of acetic acid, stir at 300rpm for 20min to obtain a coupling agent solution;

[0046] A2: Slowly add 25 mL of coupling agent solution prepared in step A1 to 500 mL of nano silica dispersion prepared in step A1. Stir at 500 rpm for 12 h at room temperature, centrifuge, wash 5 times with deionized water, and vacuum dry at 80 °C for 18 h to obtain modified nano silica.

[0047] The specific preparation steps for amino-based graphene are as follows:

[0048] B1: Add 10g of graphite powder to a flask, slowly add 250mL of concentrated sulfuric acid and 30mL of concentrated phosphoric acid, control the temperature at 4℃, stir and disperse evenly, raise the temperature to 10℃, then slowly add 30g of potassium permanganate. After the addition is complete, raise the temperature to 40℃, stir and react for 18h, then slowly add 1000mL of deionized water to dilute, then add 40mL of hydrogen peroxide, centrifuge, wash three times with deionized water and 1M HCl solution, and vacuum dry at 60℃ for 24h to obtain graphene oxide;

[0049] B2: Disperse 1500 mg of graphene oxide prepared in step B1 in 300 mL of dimethyl sulfoxide and sonicate at 150 W for 50 min to obtain a graphene oxide dispersion; control the temperature at 4 °C and slowly add 15 mL of 3-aminopropyltriethoxysilane to the graphene oxide dispersion. After the addition is complete, raise the temperature to 60 °C and stir continuously for 24 h. Centrifuge, wash three times with deionized water and ethanol, and vacuum dry at 60 °C for 24 h to obtain aminographene.

[0050] The specific preparation steps of the anti-aging electrical epoxy resin are as follows:

[0051] S1: Modified nano-silica and amino graphene were added to bisphenol A epoxy resin in a certain weight ratio, stirred at 1500 rpm for 50 min, and after being evenly dispersed, sodium dodecyl sulfate was added and stirred at 1200 rpm for 20 min. Then, polyurethane, dilauryl thiodipropionate and 2,2'-dihydroxy-4-methoxybenzophenone were added and stirred at 800 rpm for 20 min to obtain the mixed raw material.

[0052] S2: The mixed raw material prepared in step S1 is cured at 80°C for 2 hours, and then cured at 120°C for 2 hours to obtain a cured material; methyltriethoxysilane is added to 100 parts by weight of anhydrous ethanol, half the weight of the substrate is added to deionized water, and the mixture is stirred at 500 rpm for 20 minutes to obtain a hydrolysis solution.

[0053] S3: Spray the hydrolysis solution prepared in step S2 onto the surface of the cured material prepared in step S2. The spraying operation parameters are 0.3 MPa, distance 20 cm, speed 25 cm / s, and let stand for 10 min after each spraying. Spray for a total of 3 times. After spraying, vacuum dry at 80℃ for 1.5 h to obtain epoxy resin.

[0054] Example 3: An anti-aging electrical epoxy resin, comprising the following raw materials in parts by weight: 75 parts epoxy resin, 4 parts modified nano silica, 2 parts aminated graphene, 7 parts polyurethane, 0.8 parts methyltriethoxysilane, 0.3 parts sodium dodecyl sulfate, 0.8 parts antioxidant and 0.8 parts ultraviolet absorber.

[0055] The specific preparation steps for modified nano-silica are as follows:

[0056] A1: Add 10g of nano-silica to 450mL of anhydrous ethanol and sonicate at 150W for 30min to obtain a nano-silica dispersion; add 10g of γ-glycidoxypropyltrimethoxysilane to 180mL of anhydrous ethanol and stir to mix evenly, then slowly add 5.5mL of deionized water and 0.45mL of acetic acid, and stir at 250rpm for 10min to obtain a coupling agent solution;

[0057] A2: Slowly add 20 mL of coupling agent solution prepared in step A1 to 450 mL of nano silica dispersion prepared in step A1. Stir at 400 rpm for 12 h at room temperature, centrifuge, wash 5 times with deionized water, and vacuum dry at 70 °C for 12 h to obtain modified nano silica.

[0058] The specific preparation steps for amino-based graphene are as follows:

[0059] B1: Add 10g of graphite powder to a flask, slowly add 240mL of concentrated sulfuric acid and 25mL of concentrated phosphoric acid, control the temperature at 0℃, stir and disperse evenly, raise the temperature to 10℃, then slowly add 30g of potassium permanganate. After the addition is complete, raise the temperature to 38℃, stir and react for 12h, then slowly add 900mL of deionized water to dilute, then add 35mL of hydrogen peroxide, centrifuge, wash three times with deionized water and 1M HCl solution, and vacuum dry at 60℃ for 18h to obtain graphene oxide;

[0060] B2: Disperse 1200 mg of graphene oxide prepared in step B1 in 300 mL of dimethyl sulfoxide, and sonicate at 140 W for 30 min to obtain a graphene oxide dispersion; control the temperature at 0 °C, slowly add 14 mL of 3-aminopropyltriethoxysilane to the graphene oxide dispersion, after the addition is complete, raise the temperature to 60 °C, stir continuously for 18 h, centrifuge, wash three times with deionized water and ethanol, and vacuum dry at 60 °C for 18 h to obtain aminographene;

[0061] The specific preparation steps of the anti-aging electrical epoxy resin are as follows:

[0062] S1: Modified nano-silica and amino graphene were added to bisphenol A type epoxy resin in a certain weight ratio, stirred at 1400 rpm for 40 min, and after being evenly dispersed, sodium dodecyl sulfate was added and stirred at 1000 rpm for 15 min. Then polyurethane, N-phenyl-α-naphthylamine and benzyl salicylate were added and stirred at 700 rpm for 15 min to obtain mixed raw materials.

[0063] S2: The mixed raw material prepared in step S1 is cured at 80°C for 2 hours, and then cured at 120°C for 2 hours to obtain a cured material; methyltriethoxysilane is added to 100 parts by weight of anhydrous ethanol, half the weight of the substrate is added to deionized water, and the mixture is stirred at 400 rpm for 15 minutes to obtain a hydrolysis solution.

[0064] S3: Spray the hydrolysis solution prepared in step S2 onto the surface of the cured material prepared in step S2. The spraying operation parameters are 0.2 MPa, distance 18 cm, speed 30 cm / s, and let stand for 8 min after each spraying. Spray for a total of 3 times. After spraying, vacuum dry at 70℃ for 1 h to obtain epoxy resin.

[0065] Comparative Example 1: The operation of Comparative Example 1 is basically the same as that of Example 2, except that no modified nano-silica is added in Comparative Example 1.

[0066] Comparative Example 2: The operation of Comparative Example 2 is basically the same as that of Example 2, except that amino graphene is not used in Comparative Example 2.

[0067] Comparative Example 3: The operation of Comparative Example 3 is basically the same as that of Example 2, except that methyltriethoxysilane hydrophobic treatment was not used in Comparative Example 3.

[0068] Comparative Example 4: The operation of Comparative Example 4 is basically the same as that of Example 2, except that nano-silica is used instead of modified nano-silica in Comparative Example 4.

[0069] Performance testing:

[0070] Mechanical strength and insulation testing: The tensile strength, flexural strength and compressive strength of the epoxy resin material samples prepared in Examples 1-3 and Comparative Examples 1-4 were tested using a universal testing machine. The results are shown in Table 1 below. The insulation resistivity of the epoxy resin material samples prepared in Examples 1-3 and Comparative Examples 1-4 was tested according to GB / T1409-2006. The results are shown in Table 1 below.

[0071] Table 1. Test results of mechanical strength and insulation properties of epoxy resin materials

[0072] As shown in Table 1, the epoxy resin material prepared by this invention has excellent mechanical properties and insulation. Furthermore, the addition of aminated graphene did not significantly affect the insulation properties of the epoxy resin material. The results of Comparative Example 1 and Example 2 show that nano-silica, due to its high specific surface area and surface energy, can significantly enhance the hardness, rigidity, and anti-aging properties of the material. The lack of modified nano-silica leads to a significant reduction in the hardness and rigidity of the material. The results of Comparative Example 2 and Example 2 show that the addition of aminated graphene can improve the toughness and impact resistance of the material. The absence of aminated graphene may lead to increased brittleness, reduced stress transfer efficiency, and a significant decrease in mechanical strength. The results of Comparative Example 4 and Example 2 show that the lack of silane-modified nano-silica may result in poor dispersion of the nano-silica, leading to agglomeration and affecting the tensile and compressive strength of the matrix.

[0073] UV aging test: The epoxy resin material samples prepared in Example 2 and Comparative Examples 1-4 were subjected to UV lamp aging test. The test parameters were: UVA-340 lamp simulating ultraviolet light (0.35W / m). 2 The temperature was 60℃, the humidity was 55%, the light cycle was 12h light and 12h darkness, and the test was conducted for 500h. The surface condition changes of the samples were recorded at 96h, 240h and 500h. The results are shown in Table 2 below, as well as the percentage change in tensile strength (change in tensile strength = (tensile strength before test - tensile strength after test) / tensile strength before test × 100%), and the results are shown in Figure 1.

[0074] Table 2. Results of surface condition changes in epoxy resin materials after UV aging test

[0075] As shown in Table 2 and Figure 1, the epoxy resin material prepared by this invention has excellent anti-aging properties and can be used effectively for a long time. The results of Comparative Example 1 and Example 2 show that, due to the absence of modified nano-silica, the lack of filler effect prevents effective enhancement of the material's hardness and rigidity. Furthermore, the absence of nano-silica makes the material more susceptible to molecular chain breakage under ultraviolet irradiation, leading to accelerated aging and a significant decline in mechanical properties. The results of Comparative Example 2 and Example 2 show that the high thermal conductivity of graphene helps disperse heat and reduce stress concentration in localized high-temperature areas, thereby slowing down the aging of the material caused by temperature changes or ultraviolet irradiation. However, materials lacking amino-based graphene cannot form effective... The lack of a thermally conductive network may exacerbate the aging process in areas of concentrated temperature, leading to significant cracking and a marked decrease in the material's mechanical properties. The results of Comparative Example 3 and Example 2 show that the lack of hydrophobic treatment may cause moisture accumulation on the material surface. The presence of moisture accelerates the UV-induced degradation reaction, resulting in significant surface cracking, yellowing, and a marked decrease in the material's mechanical properties. The results of Comparative Example 4 and Example 2 show that the nano-silica surface lacks organic functional groups and has strong hydrophilicity, making it prone to agglomeration in epoxy resin. This may lead to uneven dispersion, affecting its reinforcing effect and resulting in a significant decrease in the material's anti-aging performance under UV irradiation.

[0076] Thermal performance test: The epoxy resin materials prepared in Example 2 and Comparative Examples 1-4 were subjected to heat distortion temperature test. The deformation temperature of the above samples was tested at 0.45 MPa and 1.8 MPa with a heating rate of 120 °C / h. The control group was bisphenol A type epoxy resin. The results are shown in Figure 2.

[0077] As shown in Figure 2, the epoxy resin material prepared by this invention exhibits an extremely high heat distortion temperature through the synergistic effect of multiple substances. The results of Comparative Example 1 and Example 2 indicate that the absence of modified nano-silica may lead to filler aggregation in the epoxy resin, resulting in poor dispersibility and compatibility, potentially leading to poor thermal properties and a lower heat distortion temperature. The results of Comparative Example 2 and Example 2 show that the absence of aminated graphene may reduce the thermal conductivity and interfacial bonding of the material, affecting the transfer of thermal stress and significantly impacting the heat distortion temperature. The results of Comparative Example 3 and Example 2 demonstrate that hydrophobic treatment improves the water resistance and corrosion resistance of the material surface, preventing erosion by moisture and corrosive media, thereby indirectly enhancing thermal properties. The lack of this treatment may cause damage to the material in humid environments, affecting its thermal stability and deformation temperature to some extent. The results of Comparative Example 4 and Example 2 show that unmodified nano-silica typically exhibits poor dispersibility in epoxy resin, and its hydrophilicity leads to weak bonding between the filler and the resin matrix, potentially resulting in a lower heat distortion temperature.

[0078] Corrosion resistance test: The epoxy resin material samples prepared in Examples 2 and Comparative Examples 1-4 were continuously sprayed with 5% NaCl solution at 35°C for 16 hours, then stopped for 8 hours, and tested for 96 hours. The percentage change in tensile strength at 24 hours, 48 ​​hours and 96 hours was recorded (tensile strength change = (tensile strength before test - tensile strength after test) / tensile strength before test × 100%). The results are shown in Figure 3.

[0079] As shown in Figure 3, the epoxy resin material prepared in this invention exhibits excellent corrosion resistance. However, the results of Comparative Example 1 and Example 2 indicate that the lack of modified nano-silica results in insufficient interfacial bonding and filler reinforcement, potentially leading to lower hardness and rigidity. This, in turn, causes deformation and aging under corrosive conditions, significantly affecting tensile strength. Furthermore, the results of Comparative Example 2 and Example 2 show that the absence of aminated graphene reduces the penetration resistance of corrosive media. The lack of graphene also prevents the material from effectively dissipating heat through the thermally conductive network and lacks physical barrier protection, resulting in poor corrosion resistance. The tensile strength is significantly affected. As can be seen from the results of Comparative Example 3 and Example 2, the hydrophobic coating can effectively prevent the intrusion of moisture and enhance the weather resistance and moisture resistance of the material through physical adsorption and hydrogen bonding. Without the hydrophobic coating, the material is more susceptible to damage from the external environment, especially in humid environments, which leads to an accelerated corrosion rate and thus affects the tensile strength. As can be seen from the results of Comparative Example 4 and Example 2, since the surface of the nano-silica does not have epoxy groups, it cannot effectively react with the epoxy resin matrix, resulting in weak interfacial bonding and thus affecting the tensile strength of the material in corrosive environments.

[0080] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An anti-aging electro-epoxy resin, characterized in that, Its composition includes the following raw materials in parts by weight: 70-80 parts epoxy resin, 3-5 parts modified nano silica, 1-3 parts aminated graphene, 5-8 parts polyurethane, 0.5-1 part methyltriethoxysilane, 0.1-0.5 parts sodium dodecyl sulfate, 0.5-1 part antioxidant and 0.5-1 part ultraviolet absorber; The specific preparation steps of the modified nano-silica are as follows: A1: Add nano-silica to anhydrous ethanol and disperse it by ultrasonication to obtain a nano-silica dispersion; add γ-glycidoxypropyltrimethoxysilane to anhydrous ethanol, stir and mix evenly, then slowly add deionized water and acetic acid, stir and react to obtain a coupling agent solution. A2: Slowly add the coupling agent solution prepared in step A1 to the nano silica dispersion prepared in step A1, stir the reaction at room temperature, centrifuge, wash repeatedly with deionized water, and vacuum dry to obtain modified nano silica.

2. The anti-aging electro-epoxy resin according to claim 1, characterized in that, The specific preparation steps of the amino-based graphene are as follows: B1: Add graphite powder to a flask, slowly add concentrated sulfuric acid and concentrated phosphoric acid, control the temperature at 0-5℃, stir and disperse evenly, raise the temperature to 10℃, then slowly add potassium permanganate. After the addition is complete, raise the temperature, stir the reaction, slowly add deionized water to dilute, then add hydrogen peroxide, centrifuge, wash repeatedly with deionized water and 1M HCl solution, and vacuum dry to obtain graphene oxide. B2: The graphene oxide prepared in step B1 is dispersed in dimethyl sulfoxide and ultrasonically dispersed to obtain a graphene oxide dispersion. The temperature is controlled at 0-5℃, and 3-aminopropyltriethoxysilane is slowly added dropwise to the graphene oxide dispersion. After the addition is complete, the temperature is raised to 60℃, and the mixture is continuously stirred, centrifuged, washed repeatedly with deionized water and ethanol, and vacuum dried to obtain aminographene.

3. The anti-aging electro-epoxy resin according to claim 2, characterized in that, The antioxidant is any one of 2,6-di-tert-butyl-p-cresol, ascorbic acid, N-phenyl-α-naphthylamine, and dilauryl thiodipropionate.

4. The anti-aging electro-epoxy resin according to claim 3, characterized in that, The ultraviolet absorber is any one of 2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, benzyl salicylate, and phenyl salicylic acid.

5. The anti-aging electro-epoxy resin according to claim 4, characterized in that, In step A1, the ratio of the amount of nano-silica to anhydrous ethanol is 1g:40-50mL; the ratio of the amount of γ-glycidoxypropyltrimethoxysilane, anhydrous ethanol, deionized water and acetic acid is 1g:15-20mL:0.5-0.6mL:0.04-0.05mL.

6. The anti-aging electro-epoxy resin according to claim 5, characterized in that, In step A2, the volume ratio of the coupling agent solution to the nano silica dispersion is 0.02 to 0.03:

1.

7. The anti-aging electro-epoxy resin according to claim 6, characterized in that, In step B1, the ratio of graphite powder, concentrated sulfuric acid, and concentrated phosphoric acid is 1g:20-25mL:2-3mL; the ratio of potassium permanganate, deionized water, hydrogen peroxide, and graphite powder is 3g:80-100mL:3-4mL:1g.

8. The anti-aging electro-epoxy resin according to claim 7, characterized in that, In step B2, the ratio of the amount of graphene oxide, dimethyl sulfoxide and 3-aminopropyltriethoxysilane is 3-5 mg: 1 mL: 0.04-0.05 mL.

9. A method for preparing an anti-aging electro-epoxy resin according to any one of claims 1-8, characterized in that, The specific preparation steps are as follows: S1: Modified nano-silica and amino graphene are added to epoxy resin in a certain weight ratio, stirred and dispersed evenly, sodium dodecyl sulfate is added and stirred, then polyurethane, antioxidant and ultraviolet absorber are added and stirred to obtain mixed raw materials. S2: The mixed raw material prepared in step S1 is cured at 80°C for 2 hours, and then cured at 120°C for 2 hours to obtain a cured material; methyltriethoxysilane is added to anhydrous ethanol, half the weight of the substrate is added to deionized water, and the mixture is stirred to obtain a hydrolysis solution. S3: Spray the hydrolysis solution prepared in step S2 onto the surface of the cured material prepared in step S2. After spraying, vacuum dry to obtain epoxy resin.

10. A method for preparing the anti-aging electro-epoxy resin according to claim 9, characterized in that, In step S3, the spraying operation parameters are 0.1-0.3 MPa, distance 15-20 cm, speed 20-30 cm / s, and stand for 5-10 minutes after each spraying, for a total of 3 sprayings.

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