Modified curing agent, epoxy resin AB glue crystal glue and preparation method of epoxy resin AB glue crystal glue

Abstract

The invention relates to the technical field of AB glue crystal glue, and discloses a modified curing agent, epoxy resin AB glue crystal glue and a preparation method of the epoxy resin AB glue crystal glue. The preparation method of the modified curing agent comprises the following steps: adding a catalyst and an epoxy curing agent into a reaction container, raising the temperature of a system to 45-50 DEG C, and adding fatty acid with stirring for 0.5 h; raising the temperature of the system to 60-70 DEG C, keeping the temperature for 2 hours, heating to 105 DEG C, vacuumizing and dehydrating for 1 hour; reducing the temperature of the system to 60-70 DEG C, adding the first epoxy resin, continuously keeping the temperature and stirring for 6 hours, and monitoring the viscosity change of the system until the viscosity of the system does not change any more to obtain the modified curing agent. According to the preparation method, the prepared modified curing agent retains the room-temperature curing characteristic, meanwhile, the humidity dependence on the environment is small, the requirement for the use environment can be reduced, and after the modified curing agent is applied to epoxy resin AB polyester resin and cured, the modified curing agent has the properties of high hardness, high transparency, yellowing resistance after curing, high weather resistance after curing and the like.

Description

Technical Field

[0001] The present application relates to the technical field of AB glue and crystal glue, and mainly to a modified curing agent, an epoxy resin AB glue and crystal glue and a preparation method thereof. Background Art

[0002] Crystal glue is popular among the public as a decoration and handicraft. The crystal glue on the market is mainly epoxy resin AB glue crystal glue and UV crystal glue. Epoxy resin crystal glue occupies an important market at this stage with its advantages of insulation, corrosion resistance, stability, heat resistance, high mechanical properties, strong cohesion, small curing shrinkage, and low cost. Epoxy resin AB glue crystal glue is composed of A glue epoxy resin as the main body and B glue curing agent as the main body. Among the epoxy resin AB glue crystal glue on the market, most of the B glue uses amine curing agent, and the use of amine curing agent has certain requirements for humidity during curing. When the humidity is greater than 70%, the surface will appear foggy, white, opaque, and wrinkled during the curing process. Therefore, generally, epoxy resin AB glue crystal glue requires air humidity between 40%-60% during curing. Therefore, in the production workshop for batch production, equipment needs to be installed to make the humidity reach the use range requirements, which will undoubtedly increase the production cost, and personal use will also be affected to a certain extent by the environment, affecting the performance of epoxy resin AB glue crystal glue. Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the purpose of the present application is to provide a modified curing agent, an epoxy resin AB glue crystal glue and a preparation method thereof, aiming to solve the problem that the existing B glue epoxy resin AB glue crystal glue using an amine curing agent exhibits surface fogging, whitening, opacity and wrinkling when cured in a high humidity environment.

[0004] The technical solution of this application is as follows: In a first aspect, the present application provides a method for preparing a modified curing agent, which comprises the following steps: Add the catalyst and epoxy curing agent into the reaction vessel, raise the system temperature to 45-50°C, add the fatty acid with stirring, and the addition process takes 0.5h; Then the system temperature was raised to 60-70°C, kept warm for 2 hours, and then heated to 105°C, and vacuumed for dehydration for 1 hour; The system temperature is lowered to 60-70° C., the first epoxy resin is added, and the mixture is stirred for 6 hours while maintaining the temperature. The viscosity change of the system is monitored until the viscosity of the system no longer changes, and the modified curing agent is obtained.

[0005] The modified curing agent provided in the present application can reduce the dependence on environmental humidity during curing, and can reduce the requirements for the use environment. When used in the curing of epoxy resin AB glue and crystal glue, it has high hardness, high transparency, yellowing resistance after curing, high weather resistance after curing and other properties.

[0006] Furthermore, the epoxy curing agent is one or two of polyetheramine D200, polyetheramine D230, curing agent 593, and isophorone diamine.

[0007] In the present application, the selected epoxy curing agent has good room temperature curing performance. Through the provided preparation method, the epoxy curing agent is modified to improve the curing performance under high humidity. The product after curing under low humidity is also brighter, more transparent and has higher hardness.

[0008] Furthermore, the fatty acid is one of eleostearic acid and linoleic acid.

[0009] In the present application, fatty acids are used to extend the chain of epoxy curing agent, thereby increasing the carbon chain, enhancing the hydrophobicity, reducing the influence of water vapor under high humidity, and ensuring the transparency after curing.

[0010] Furthermore, the first epoxy resin is one of a polymer of 4,4'-(1-methylethylene)bisphenol and (chloromethyl)ethylene oxide and 2,2-bis-(4-glycolylaminophenyl)propane.

[0011] Further, in the preparation method of the modified curing agent, the weight ratio of the first epoxy resin, fatty acid and epoxy curing agent added is 10:5:85; The catalyst is one or two of boron trifluoride, aluminum trichloride, organotin and organobismuth; The added weight of the catalyst is 0.05% of the total added weight of the first epoxy resin, fatty acid and epoxy curing agent.

[0012] In a second aspect, the present application further provides a modified curing agent, wherein the modified curing agent is prepared by the preparation method of the modified curing agent as described in the first aspect.

[0013] In a third aspect, the present application further provides an epoxy resin AB glue crystal glue resistant to high humidity curing, comprising glue A and glue B, wherein the glue A comprises the following components by weight: 85-90 parts of a second epoxy resin, 10-15 parts of a reactive diluent, and 0.5-1 part of an anti-yellowing additive; The B glue comprises the following components by weight: 95-97 parts of the modified curing agent as described in the second aspect and 3-5 parts of alkyl primary amine.

[0014] Furthermore, the active diluent is one or two of n-butyl glycidyl ether, allyl glycidyl ether, and propylene carbonate; The second epoxy resin is one of a polymer of 4,4'-(1-methylethylene)bisphenol and (chloromethyl)ethylene oxide and 2,2-bis-(4-glycolylaminophenyl)propane.

[0015] Further, the alkyl primary amine is one of octadecylamine and hexadecylamine; The anti-yellowing aid is one or two of antioxidant 1010, UV-9 ultraviolet absorber, and ultraviolet absorber 326.

[0016] In a fourth aspect, the present application further provides a method for preparing the high humidity curing resistant epoxy resin AB glue crystal glue as described in the third aspect, wherein the method comprises the following steps: The second epoxy resin, the active diluent and the anti-yellowing aid are added to a reaction container in parts by weight, heated to 35-40° C., dispersed for 15-20 minutes by a high-speed disperser at a stirring speed of 1000-1200 rpm, and then vacuumed and degassed to obtain the A glue; The modified curing agent and alkyl primary amine are added into a reaction container according to weight proportions, heated to 35-40° C., dispersed for 15-20 minutes by a high-speed disperser with a stirring speed of 1000-1200 rpm, and then vacuumed and degassed to obtain the B glue.

[0017] Beneficial effects: The present application modifies the epoxy curing agent, extends the chain through fatty acids, reduces the amino content in the molecule, and increases the molecular weight, thereby enhancing the hydrophobicity and further enhancing the moisture resistance, so that it can be cured normally under high humidity conditions and retains the original room temperature curing characteristics. The cured product has high hardness, high transparency and other characteristics. DETAILED DESCRIPTION

[0018] The present application provides a modified curing agent, an epoxy resin AB glue crystal glue and a preparation method thereof. To make the purpose, technical scheme and effect of the present application clearer and more specific, the present application is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0019] Among the existing AB glues, amine curing agents have a relatively small molecular weight, so they are suitable for room temperature curing, and the cured product has high hardness and high transparency. However, due to the strong water solubility of the amino group in its structure, it is more sensitive to humidity and easily absorbs moisture in the air, resulting in whitening, fogging, and wrinkling on the surface during curing.

[0020] To solve this problem, the present application provides a method for preparing a modified curing agent, which comprises the following steps: S1. Add a catalyst and an epoxy curing agent into a reaction vessel, raise the system temperature to 45-50°C, and add fatty acid with stirring. The addition process takes 0.5h. S2, then raise the system temperature to 60-70°C, keep warm for 2 hours, then heat to 105°C, and evacuate to perform dehydration for 1 hour; S3. Lower the temperature to 60-70°C, add epoxy resin, continue to keep warm and stir for 6 hours, monitor the change in system viscosity until the system viscosity no longer changes to obtain the modified curing agent.

[0021] The epoxy curing agent is modified by the preparation method provided in the present application, and the chain is extended by fatty acids to reduce the content of amino groups in the molecule, thereby increasing the molecular weight, thereby enhancing the hydrophobicity and further enhancing the moisture resistance, so that it can be cured normally under high humidity conditions and retain the original room temperature curing characteristics. The cured product has high hardness, high transparency and other characteristics.

[0022] Further, the epoxy curing agent is one or two of polyetheramine D200, polyetheramine D230, curing agent 593, and isophorone diamine. In the present application, the selected epoxy curing agent has good room temperature curing performance. Through the preparation method provided in the present application, the amine epoxy curing agent is modified to improve the curing performance under high humidity. The product after curing under low humidity is also brighter and more transparent, and has high hardness. At the same time, after being modified, the original room temperature curing characteristics can be maintained, which is convenient for curing.

[0023] Furthermore, the fatty acid is one of eleostearic acid and linoleic acid. In the present application, the fatty acid is used to extend the chain of the epoxy curing agent, so that the carbon chain is increased, the hydrophobic property is enhanced, the influence of water vapor under high humidity is reduced, and the transparency after curing is ensured.

[0024] Further, the first epoxy resin is one of a polymer of 4,4'-(1-methylethylidene)bisphenol and (chloromethyl)oxirane, and 2,2-bis-(4-glycolylaminophenyl)propane. In the present application, the selected epoxy resin takes into account the reaction performance when preparing the modified curing agent. The selected epoxy resin has a suitable molecular weight and epoxy equivalent, and has high reaction performance while maintaining its own low viscosity, which is conducive to maintaining the good curing ability of the prepared modified curing agent.

[0025] Further, in the preparation method of the modified curing agent, the weight ratio of the first epoxy resin, fatty acid and epoxy curing agent is: (first epoxy resin: fatty acid: epoxy curing agent = 10:5:85). In the present application, the changes in the amount of the first epoxy resin, fatty acid and epoxy curing agent will affect the overall performance of the modified curing agent. The appropriate ratio is explored through experiments to balance the comprehensive performance of the modified curing agent. This ratio is suitable for fine-tuning. Among them, if the addition ratio of epoxy resin is too high, the overall viscosity of the modified curing agent will increase, which will cause the AB glue to be difficult to foam when mixed. If the addition ratio of the curing agent is too high, the humidity resistance will decrease, and the modification effect will not be obvious. If the content of fatty acid is too high, the yellowing resistance after curing will deteriorate. Under the provided ratio, the good curing effect of the modified curing agent can be guaranteed.

[0026] In the present application, the selected epoxy curing agent has an amino group, and the fatty acid and the epoxy curing agent react in step S1, and the carboxyl group in the fatty acid and the amino group in the epoxy curing agent are dehydrated and condensed, and the long carbon chain of the fatty acid is introduced into the epoxy curing agent, and the content of the amino group in the curing agent system can be reduced at the same time. After the reaction, the introduced long carbon chain can enhance the hydrophobic property. At the same time, it can also make the prepared modified curing agent have a higher compatibility with the alkyl primary amine used together in the subsequent B glue, avoiding the generation of curing defects due to the insufficient compatibility of the B glue. Specifically, taking the reaction of eleostearic acid and polyetheramine D230 as an example, the reaction formula is as follows: .

[0027] Specifically, after step S1, water will be generated in the reaction system. By removing the water in step S2, the subsequent reaction and the performance of the modified curing agent are avoided from being affected.

[0028] In the present application, by reacting the epoxy resin with the epoxy curing agent in step S3, the content of the amino group in the epoxy curing agent can be further reduced while maintaining the reaction activity. Specifically, taking the reaction of 2,2-bis-(4-glycolaminophenyl)propane and polyetheramine D230 as an example, the reaction formula is as follows: .

[0029] Furthermore, the catalyst is one or two of boron trifluoride, aluminum trichloride, organic tin, and organic bismuth; the added weight of the catalyst is 0.05% of the total amount of the first epoxy resin, fatty acid, and epoxy curing agent.

[0030] By adjusting the curing properties of the epoxy curing agent through the preparation method provided in the present application, a modified curing agent with good overall curing properties can be obtained, which can also maintain good curing properties under high humidity and avoid the problem of fogging during curing.

[0031] The present application also provides a modified curing agent, wherein the modified curing agent is prepared by the preparation method of the modified curing agent as described above. The prepared modified curing agent can be well applied to epoxy resin crystal glue to improve its curing performance and help improve the apparent performance after curing.

[0032] The present application also provides an epoxy resin AB glue crystal glue resistant to high humidity curing, comprising glue A and glue B, wherein glue A comprises the following components by weight: 85-90 parts of a second epoxy resin, 10-15 parts of a reactive diluent, and 0.5-1 part of an anti-yellowing additive; The B glue comprises the following components by weight: 95-97 parts of the modified curing agent as described above, and 3-5 parts of the alkyl primary amine; The modified curing agent provided in the present application can reduce the dependence of epoxy resin AB glue and crystal glue on environmental humidity during curing, and can reduce the requirements for the use environment. The prepared epoxy resin AB glue and crystal glue not only has the original room temperature curing characteristics, but also maintains high hardness, high transparency, yellowing resistance after curing, and high weather resistance after curing.

[0033] Specifically, the mass ratio of A glue and B glue in the high humidity resistant curing epoxy resin AB glue crystal glue is 2:1.

[0034] Furthermore, the active diluent is one or two of n-butyl glycidyl ether, allyl glycidyl ether and propylene carbonate. In the present application, the active diluent selected can reduce the overall viscosity, so that the bubbles generated after the mixture of glue A and glue B are easily eliminated, and the active diluent selected also has a certain reaction ability, and can ensure the degree of transparency and brightness after participating in the curing. Among them, the amino group in the modified curing agent of the present application has been adjusted, and the addition ratio of the active diluent should not be too high, which will reduce the overall reaction speed of the crystal glue.

[0035] Furthermore, the second epoxy resin is one of a polymer of 4,4'-(1-methylethylidene)bisphenol and (chloromethyl)oxirane, and 2,2-bis-(4-glycolylaminophenyl)propane. In the present application, the selected second epoxy resin has good curing performance and is relatively consistent with the properties of the modified curing agent, which is conducive to ensuring high transparency of the cured product and avoiding defects.

[0036] Furthermore, the alkyl primary amine is one of octadecylamine and hexadecylamine. In the present application, the selected octadecylamine and hexadecylamine can play a hydrophobic role, can increase the hydrophobicity of the entire system, and at the same time act on the crystal glue curing reaction process, reduce the influence of moisture, and help improve transparency. Among them, the addition ratio of the alkyl primary amine should not be too high, which will reduce the reaction speed.

[0037] The present application can overcome the problem that the amine curing agent absorbs water during curing under high humidity conditions, causing the surface to become foggy, wrinkled, and opaque by modifying the epoxy curing agent and adding an alkyl primary amine.

[0038] Furthermore, the anti-yellowing aid is one or two of antioxidant 1010, UV-9 ultraviolet absorber, and ultraviolet absorber 326.

[0039] The present application also provides a method for preparing the epoxy resin AB glue crystal glue resistant to high humidity curing as described above, which comprises the following steps: Add the second epoxy resin, the active diluent and the anti-yellowing additive into a reaction container according to weight, heat, stir and then vacuum degas to obtain glue A; Add the modified curing agent and the alkyl primary amine into a reaction container according to weight, heat, stir, and then vacuum and degas to obtain glue B; In the preparation method, the heating temperature is 35-40°C and the heating time is 15-20 minutes; In the preparation method, the stirring is performed by a high-speed disperser, the stirring speed is 1000-1200 rpm, and the dispersion time is 15-20 minutes.

[0040] The preparation method provided in the present application is simple and easy to implement, and is suitable for batch industrial production.

[0041] The invention is further described below by means of specific examples.

[0042] The preparation method of the modified curing agent used in the examples of the present application comprises the following steps: Add the catalyst and epoxy curing agent into the reaction vessel, raise the system temperature to 50°C, and add the fatty acid with stirring. The addition process takes 0.5h. The system temperature was then raised to 70°C, kept at this temperature for 2 h, and then heated to 105°C, and vacuumed for dehydration for 1 h; The system temperature was lowered to 65° C., the first epoxy resin was added, and the mixture was stirred for 6 hours at a constant temperature. The viscosity of the system was monitored until the viscosity of the system stopped changing. Then, the modified curing agent was obtained.

[0043] The epoxy curing agent is polyetheramine D230, the fatty acid is eleostearic acid, the first epoxy resin is 2,2-bis-(4-glycolylaminooxyphenyl)propane, and the weight ratio of 2,2-bis-(4-glycolylaminooxyphenyl)propane, eleostearic acid and polyetheramine D230 is 10:5:85. The catalyst is organic tin, and the added weight is 0.05% of the total amount of 2,2-bis-(4-glycolylaminooxyphenyl)propane, eleostearic acid and polyetheramine D230.

[0044] Example 1 The high humidity resistant curing epoxy resin AB glue crystal glue of Example 1 is prepared by mixing glue A and glue B in a weight ratio of 2:1; Glue A includes the following components by weight: 85 parts of 2,2-bis-(4-glycolylaminophenyl)propane, 15 parts of propylene carbonate, and 0.5 parts of UV-9 ultraviolet absorber; each component is poured into a reaction container at once, heated to 40° C., dispersed with a high-speed disperser at a stirring speed of 1200 rpm for 20 minutes, and vacuumed and degassed to obtain glue A; Glue B includes the following components by weight: 95 parts of modified curing agent and 5 parts of hexadecylamine. Pour all components into a reaction kettle at once, heat to 40°C, disperse with a high-speed disperser at a stirring speed of 1200 rpm for 20 minutes, and vacuum degas to obtain glue B.

[0045] Example 2 The high humidity resistant curing epoxy resin AB glue crystal glue of Example 2 is prepared by mixing glue A and glue B in a weight ratio of 2:1; Glue A includes the following components by weight: 87 parts of 2,2-bis-(4-glycolylaminophenyl)propane, 13 parts of propylene carbonate, and 0.5 parts of UV-9 ultraviolet absorber; each component is poured into a reaction container at once, heated to 40° C., dispersed with a high-speed disperser at a stirring speed of 1200 rpm for 20 minutes, and vacuumed and degassed to obtain glue A; Glue B includes the following components by weight: 95 parts of modified curing agent and 5 parts of hexadecylamine. Pour all components into a reaction kettle at once, heat to 40°C, disperse with a high-speed disperser at a stirring speed of 1200 rpm for 20 minutes, and vacuum degas to obtain glue B.

[0046] Example 3 The high humidity resistant curing epoxy resin AB glue crystal glue of Example 3 is prepared by mixing glue A and glue B in a weight ratio of 2:1; Glue A includes the following components by weight: 90 parts of 2,2-bis-(4-glycolylaminophenyl)propane, 10 parts of propylene carbonate, and 0.5 parts of UV-9 ultraviolet absorber; each component is poured into a reaction container at once, heated to 40° C., dispersed with a high-speed disperser at a stirring speed of 1200 rpm for 20 minutes, and vacuumed and degassed to obtain glue A; Glue B includes the following components by weight: 95 parts of modified curing agent and 5 parts of hexadecylamine. Pour all components into a reaction kettle at once, heat to 40°C, disperse with a high-speed disperser at a stirring speed of 1200 rpm for 20 minutes, and vacuum degas to obtain glue B.

[0047] The performance of the high humidity resistant epoxy resin AB glue crystal glue prepared in Examples 1-3 was tested. The curing test results of Examples 1-3 under different humidity environments are shown in Table 1: Table 1 Test items Example 1 Example 2 Example 3 25℃, 60% humidity The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles 25℃, 70% humidity The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles 25℃, 75% humidity The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles 25℃, 80% humidity The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles 25℃, 90% humidity The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles The surface is bright, transparent, without white fog and wrinkles The high humidity resistant curing epoxy resin AB glue crystal glue prepared in Examples 1-3 can maintain good curing performance under different humidity conditions, is not easy to absorb water, and does not have the problems of surface fogging, wrinkling, and opacity even under a high humidity of 90%.

[0048] Comparative Example 1 The AB glue crystal glue of comparative example 1 is prepared by mixing glue A and glue B in a weight ratio of 3:1; Glue A is the same as glue A in Example 1; Only epoxy curing agent 593 is used for B glue.

[0049] Comparative Example 2 The AB glue crystal glue of comparative example 2 is prepared by mixing glue A and glue B in a weight ratio of 3:1; Glue A is the same as glue A in Example 1; B glue only uses polyetheramine D230.

[0050] Comparative Example 3 The AB glue crystal glue of comparative example 3 is prepared by mixing glue A and glue B in a weight ratio of 3:1; Glue A is the same as glue A in Example 1; B glue uses only isophorone diamine.

[0051] The performance test of the AB glue crystal glue prepared in Comparative Examples 1-3 was carried out. The curing test results of Comparative Examples 1-3 under different humidity environments are shown in Table 2: Table 2 Test items Comparative Example 1 Comparative Example 2 Comparative Example 3 25℃, 60% humidity The surface is wrinkled and opaque The surface is bright, transparent, without white fog and wrinkles The surface is wrinkled and opaque 25℃, 70% humidity The surface is wrinkled and opaque The surface is bright, transparent, without white fog and wrinkles The surface is wrinkled and opaque 25℃, 75% humidity The surface is wrinkled and opaque The surface is foggy and wrinkled The surface is wrinkled and opaque 25℃, 80% humidity The surface is wrinkled and opaque The surface is foggy and wrinkled The surface is wrinkled and opaque The AB glue crystal glue of Comparative Examples 1 and 3 showed wrinkles and opacity on the surface when cured under different humidity environments. The curing performance of Comparative Example 2 was better at 60% humidity and 70% humidity, but fogging and wrinkling occurred at 75% humidity and 80% humidity.

[0052] The performance comparison of Comparative Example 2 and Examples 1, 2, and 3 after curing at 75% humidity is shown in Table 3: Table 3 Test items Comparative Example 2 Example 1 Example 2 Example 3 Surface appearance Opaque, wrinkled Bright and transparent Bright and transparent Bright and transparent Hardness (Shore D) 82D 81D 82D 82D 1 week outside after curing Yellowing in less than a week (more serious than indoors) No yellowing (no change compared to indoor) No yellowing (no change compared to indoor) No yellowing (no change compared to indoor) The epoxy resin AB glue crystal glue with high humidity curing resistance provided in the embodiment of the present application can overcome the problem that the amine curing agent absorbs water during curing under high humidity conditions, causing the surface to become foggy, wrinkled, and opaque. At the same time, the cured product has the characteristics of high hardness, high transparency, and yellowing resistance.

[0053] It should be understood that the application of the present application is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made according to the above description, and all these improvements and changes should fall within the scope of protection of the present application.

Claims

1. A method for preparing a modified curing agent, characterized in that: The following steps are involved: Add the catalyst and epoxy curing agent into the reaction vessel, raise the system temperature to 45-50°C, add the fatty acid with stirring, and the addition process takes 0.5h; Then the system temperature was raised to 60-70°C, kept warm for 2 hours, and then heated to 105°C, and vacuumed for dehydration for 1 hour; The system temperature is lowered to 60-70° C., the first epoxy resin is added, and the mixture is stirred for 6 hours while maintaining the temperature. The viscosity change of the system is monitored until the viscosity of the system no longer changes, and the modified curing agent is obtained.

2. The method for preparing a modified curing agent according to claim 1, characterized in that: The epoxy curing agent is one or two of polyetheramine D200, polyetheramine D230, curing agent 593, and isophorone diamine.

3. The method for preparing a modified curing agent according to claim 2, characterized in that: The fatty acid is one of eleostearic acid and linoleic acid.

4. The method for preparing a modified curing agent according to claim 3, characterized in that: The first epoxy resin is one of a polymer of 4,4'-(1-methylethylene)bisphenol and (chloromethyl)ethylene oxide and 2,2-bis-(4-glycolylaminophenyl)propane.

5. The method for preparing a modified curing agent according to claim 4, characterized in that: In the preparation method of the modified curing agent, the weight ratio of the first epoxy resin, fatty acid and epoxy curing agent added is 10:5:85; The catalyst is one or two of boron trifluoride, aluminum trichloride, organotin and organobismuth; The added weight of the catalyst is 0.05% of the total added weight of the first epoxy resin, fatty acid and epoxy curing agent.

6. A modified curing agent, characterized in that: The modified curing agent is prepared by the preparation method of the modified curing agent according to any one of claims 1 to 5.

7. An epoxy resin AB glue crystal glue resistant to high humidity curing, comprising A glue and B glue, characterized in that: The A glue comprises the following components by weight: 85-90 parts of a second epoxy resin, 10-15 parts of a reactive diluent, and 0.5-1 parts of an anti-yellowing additive; The B glue is measured by weight. Includes the following components: 95-97 parts of the modified curing agent as claimed in claim 6 and 3-5 parts of the alkyl primary amine.

8. The high humidity resistant curing epoxy resin AB glue crystal glue according to claim 7, characterized in that: The active diluent is one or two of n-butyl glycidyl ether, allyl glycidyl ether and propylene carbonate; The second epoxy resin is one of a polymer of 4,4'-(1-methylethylene)bisphenol and (chloromethyl)ethylene oxide and 2,2-bis-(4-glycolylaminophenyl)propane.

9. The high humidity resistant curing epoxy resin AB glue crystal glue according to claim 7, characterized in that: The alkyl primary amine is one of octadecylamine and hexadecylamine; The anti-yellowing aid is one or two of antioxidant 1010, UV-9 ultraviolet absorber, and ultraviolet absorber 326.

10. A method for preparing the high humidity resistant curing epoxy resin AB glue crystal glue as claimed in any one of claims 7 to 9, characterized in that: The following steps are involved: The second epoxy resin, the active diluent and the anti-yellowing aid are added to a reaction container in parts by weight, heated to 35-40° C., dispersed for 15-20 minutes by a high-speed disperser at a stirring speed of 1000-1200 rpm, and then vacuumed and degassed to obtain the A glue; The modified curing agent and alkyl primary amine are added into a reaction container according to weight proportions, heated to 35-40° C., dispersed for 15-20 minutes by a high-speed disperser with a stirring speed of 1000-1200 rpm, and then vacuumed and degassed to obtain the B glue.