An epoxy resin composition, a method of preparation and use

Abstract

The application discloses an epoxy resin composition, which comprises an A component and a B component, the A component comprises an epoxy resin, and the B component comprises a first curing agent and a second curing agent. The first curing agent is a curing agent containing two active hydrogens, and the second curing agent is selected from one of an amine curing agent with an active hydrogen number of greater than or equal to 3, a mercapto curing agent with an active hydrogen number of greater than or equal to 3 or an acid anhydride curing agent. The first curing agent and the second curing agent constitute a co-curing system, the first curing agent has only two active hydrogens in a molecular structure, only plays a chain extension role in a curing reaction, and has a free volume in a region greater than that of a curing region of the second curing agent. By selecting the first curing agent and the second curing agent with different main chain structure categories as the co-curing system, the epoxy resin composition can simultaneously have improved heat resistance, cracking resistance, voltage resistance and mechanical strength and the like while improving electrical insulation performance and Tg of the epoxy resin composition.

Description

An epoxy resin composition, its preparation method and its application Technical Field

[0001] This invention relates to the field of materials, and more particularly to an epoxy resin composition. Background Technology

[0002] Epoxy resins are polymers containing two or more epoxy groups in their molecular structure. These epoxy groups can react with curing agents (anhydrides, amines, etc.) to form cross-linked cured products.

[0003] Cable accessories are an essential component of cable connection lines. With the development of high-voltage cross-linked cables in my country, the demand for corresponding cable accessories is increasing. High-voltage cable accessories operate in harsh environments. Whether it's the terminal bushings of GIS systems, the stress cone sleeves of terminals, transformer end bushings, or the shells of intermediate joints, the materials used must possess high mechanical, physical, and electrical properties. Epoxy resin, as a power insulation material, has excellent electrical insulation, mechanical, adhesive, and corrosion resistance properties, while also possessing advantages such as low dielectric loss, low curing shrinkage, low linear expansion coefficient, low water absorption, and good dimensional stability.

[0004] Epoxy resin compositions used for high-voltage electrical insulation must possess good thermomechanical properties, electrical insulation properties, voltage withstand properties, heat resistance, crack resistance, and mechanical properties. However, it is difficult to simultaneously achieve all these properties. Summary of the Invention

[0005] The main objective of this invention is to solve the above-mentioned problems and provide an epoxy resin composition with excellent electrical insulation, voltage resistance, heat resistance, high and low temperature impact resistance, crack resistance, and mechanical strength.

[0006] The above-mentioned objective of this invention is achieved through the following technical solution:

[0007] In a first aspect, the present invention provides an epoxy resin composition comprising component A and component B;

[0008] Component A includes epoxy resin; component B includes a first curing agent and a second curing agent.

[0009] The first curing agent is a curing agent containing two active hydrogen atoms;

[0010] The second curing agent is selected from one of the following: amine curing agents with ≥3 active hydrogens, mercapto curing agents with ≥3 active hydrogens, or acid anhydride curing agents.

[0011] In some embodiments of this application, the epoxy resin includes at least one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin.

[0012] In some embodiments of this application, the first curing agent includes at least one of bisphenol hydroxyl curing agents, biscarboxyl curing agents, bisimine curing agents, bisthiol curing agents, or curing agents containing any two of the following groups: phenolic hydroxyl, thiol, carboxyl, and imine.

[0013] In some embodiments of this application, the first curing agent is selected from at least one of bisphenol A, hydroquinone and 4,4'-biphenyl, sebacic acid, terephthalic acid, 4,4'-bis-sec-butylaminodiphenylmethane, 4,4'-diacetamidodiphenylmethane, 2-dimercaptoethyl sulfide, and 2,2'-(1,2-ethylenedioxy)diethyl mercaptan.

[0014] In some embodiments of this application, the amine curing agent with ≥3 active hydrogens includes at least one of linear aliphatic amines, alicyclic amines, and aromatic amines.

[0015] In some embodiments of this application, the thiol-based curing agent with ≥3 active hydrogens includes at least one of linear aliphatic thiol, alicyclic thiol, and aromatic thiol.

[0016] In some embodiments of this application, the anhydride curing agent includes at least one of aromatic anhydrides, alicyclic anhydrides, or linear aliphatic anhydrides.

[0017] In some embodiments of this application, the amine curing agent with ≥3 active hydrogen atoms is selected from at least one of 4,4'-diaminodiphenylmethane, triethylenetetramine, isophorone diamine, 4,4'-diaminodiphenyl sulfone, polyetheramine, polyesteramine, 4,4'-oxodiphenylamine, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine.

[0018] In some embodiments of this application, the mercapto-based curing agent with ≥3 active hydrogen atoms is selected from at least one of trimethylolpropane tris(2-mercaptoacetate), pentaerythritol tetramercaptoacetate, tetramercaptobenzene, p-mercaptoterephthalic acid, hexamercaptotriethylene, tris[2-(3-mercaptopropionic acid)ethyl]isocyanuric acid, 2,3-dimercaptosuccinic acid, trimercaptotriazine, and 6-pentaerythritol tetra(3-mercaptobutyrate).

[0019] In some embodiments of this application, the anhydride curing agent is selected from at least one of methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, 2,2-dimethylglutaric anhydride, 2,3-dimethylsuccinic anhydride, glutaric anhydride, succinic anhydride, triphenylhexacarboxylic anhydride, 4,4'-biphenyl ether dianhydride, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, and methylnadic anhydride.

[0020] In some embodiments of this application, the mass parts of each component of the epoxy resin composition are as follows:

[0021] Epoxy resin: 100 parts;

[0022] First curing agent: 1-20 parts;

[0023] When the second curing agent is an amine with ≥3 active hydrogens or a mercapto-based curing agent with ≥3 active hydrogens, the mass fraction of the second curing agent is Cg[ab / 100-2e / f] / h, where a is the mass fraction of epoxy resin (in g), b is the epoxy value of epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), h is the number of active hydrogens contained in the second curing agent, g is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2;

[0024] When the second curing agent is an anhydride-based curing agent, the mass fraction of the second curing agent is Ck[ab / 100-2e / f] / j, where a is the mass fraction of epoxy resin (in g), b is the epoxy value of epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), j is the number of anhydride groups contained in the second curing agent, k is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2.

[0025] In some embodiments of this application, the epoxy resin is a first epoxy resin and a second epoxy resin. The first epoxy resin is selected from one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin. The second epoxy resin is selected from one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin.

[0026] In some embodiments of this application, the epoxy values ​​of the first epoxy resin and the second epoxy resin are 0.2-0.9 mol / 100g, and the epoxy value of the first epoxy resin is less than that of the second epoxy resin.

[0027] In some embodiments of this application, the mass parts of each component of the epoxy resin composition are as follows:

[0028] First epoxy resin: 70-100 parts;

[0029] Second epoxy resin: 1-30 parts;

[0030] First curing agent: 1-20 parts;

[0031] When the second curing agent is an amine with ≥3 active hydrogens or a mercapto-based curing agent with ≥3 active hydrogens, the mass fraction of the second curing agent is Cg[(ab+cd) / 100-2e / f] / h, where a is the mass fraction of the first epoxy resin (in g), b is the epoxy value of the first epoxy resin (in mol / 100g), c is the mass fraction of the second epoxy resin (in g), d is the epoxy value of the second epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), h is the number of active hydrogens contained in the second curing agent, g is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2;

[0032] When the second curing agent is an anhydride-based curing agent, the mass fraction of the second curing agent is Ck[(ab+cd) / 100-2e / f] / j, where a is the mass fraction of the first epoxy resin (in g), b is the epoxy value of the first epoxy resin (in mol / 100g), c is the mass fraction of the second epoxy resin (in g), d is the epoxy value of the second epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (in g / mol), j is the number of anhydride groups contained in the second curing agent, k is the molar mass of the second curing agent (in g / mol), and C is a correction factor, 0.8≤C≤1.2.

[0033] In some embodiments of this application, the epoxy resin composition further includes 1-350 parts of filler, the filler including at least one selected from alumina, silica powder, silica, magnesium oxide, boron nitride, kaolin and zinc oxide.

[0034] In a second aspect, the present invention provides a method for preparing the above-mentioned epoxy resin composition, the method comprising the preparation of component A and component B;

[0035] The preparation method of component A includes: mixing epoxy resin evenly and degassing it under vacuum under certain conditions to obtain component A;

[0036] The preparation method of component B includes: mixing the first curing agent and the second curing agent evenly, and then dehydrating and degassing them under vacuum under certain conditions to obtain component B;

[0037] The epoxy resin composition is obtained by mixing component A and component B, injecting the mixture into a mold, and curing it under certain conditions.

[0038] In some embodiments of this application, if the epoxy resin is the first epoxy resin and the second epoxy resin, the preparation method of component A includes: mixing the first epoxy resin and the second epoxy resin evenly, and degassing under vacuum under certain conditions to obtain component A;

[0039] Alternatively, the preparation method of component A includes: mixing the first epoxy resin and the second epoxy resin evenly, dehydrating and degassing the filler under certain conditions, and adding the pretreated filler to the resin mixture to obtain component A;

[0040] Alternatively, the preparation method of component B includes: mixing the first curing agent and the second curing agent evenly, and dehydrating and degassing them under certain conditions to obtain component B.

[0041] In a third aspect, the present invention provides an epoxy resin composition for the preparation of insulating components in electronic and electrical equipment.

[0042] The epoxy resin composition of this invention comprises component A and component B. Component A comprises epoxy resin; component B comprises a first curing agent and a second curing agent. The first curing agent is a curing agent containing two active hydrogen atoms, and the second curing agent is selected from one of the following: amine curing agents with ≥3 active hydrogen atoms, mercapto curing agents with ≥3 active hydrogen atoms, or acid anhydride curing agents. The first and second curing agents constitute a co-curing system. The first curing agent has only two active hydrogen atoms in its molecular structure and only plays a chain-extending role in the curing reaction; its free volume is larger than that of the curing region of the second curing agent. By selecting first and second curing agents with different main chain structures as a co-curing system, it is possible to improve the electrical insulation properties and Tg of the epoxy resin composition while simultaneously improving its heat resistance, crack resistance, voltage resistance, and mechanical strength. Detailed Implementation

[0043] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0044] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the 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.

[0045] In this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0046] Epoxy resins are polymers containing two or more epoxy groups in their molecular structure. These epoxy groups can react with curing agents (anhydrides, amines, etc.) to form cross-linked cured products.

[0047] Cable accessories are an essential component of cable connection lines. With the development of high-voltage cross-linked cables in my country, the demand for corresponding cable accessories is increasing. High-voltage cable accessories operate in harsh environments. Whether it's the terminal bushings of GIS systems, the stress cone sleeves of terminals, transformer end bushings, or the shells of intermediate joints, the materials used must possess high mechanical, physical, and electrical properties. Epoxy resin, as a power insulation material, has excellent electrical insulation, mechanical, adhesive, and corrosion resistance properties, while also possessing advantages such as low dielectric loss, low curing shrinkage, low linear expansion coefficient, low water absorption, and good dimensional stability.

[0048] Epoxy resin compositions used for high-voltage electrical insulation must possess good electrical insulation properties, voltage resistance, heat resistance, resistance to high and low temperature impacts, crack resistance, mechanical strength, and chemical stability. However, it is difficult to simultaneously achieve good electrical insulation properties, voltage resistance, heat resistance, mechanical strength, and crack resistance.

[0049] In a first aspect, the present invention provides an epoxy resin composition comprising component A and component B;

[0050] Component A includes epoxy resin; component B includes a first curing agent and a second curing agent.

[0051] The first curing agent is a curing agent containing two active hydrogen atoms;

[0052] The second curing agent is selected from one of the following: amine curing agents with ≥3 active hydrogens, mercapto curing agents with ≥3 active hydrogens, or acid anhydride curing agents.

[0053] It should be noted that active hydrogen is a hydrogen atom that can undergo a ring-opening reaction with an epoxy group under certain conditions.

[0054] The epoxy resin composition of this invention comprises component A and component B. Component A comprises epoxy resin; component B comprises a first curing agent and a second curing agent. The first curing agent is a curing agent containing two active hydrogen atoms, and the second curing agent is selected from one of the following: amine curing agents with ≥3 active hydrogen atoms, mercapto curing agents with ≥3 active hydrogen atoms, or acid anhydride curing agents. The first and second curing agents constitute a co-curing system. The first curing agent has only two active hydrogen atoms in its molecular structure and only plays a chain-extending role in the curing reaction; its free volume is larger than that of the curing region of the second curing agent. By selecting first and second curing agents with different main chain structures as a co-curing system, it is possible to improve the electrical insulation properties and Tg of the epoxy resin composition while simultaneously improving its heat resistance, crack resistance, voltage resistance, and mechanical strength.

[0055] In some embodiments of this application, the epoxy resin includes at least one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin.

[0056] In some embodiments of this application, the first curing agent includes at least one of the following: a bisphenol hydroxyl curing agent containing two active hydrogen atoms, a biscarboxyl curing agent, a bisimine curing agent, a bisthiol curing agent, or a curing agent containing any two of the following groups: phenolic hydroxyl, thiol, carboxyl, and imine.

[0057] Specifically, the structural formula of bisphenol hydroxyl curing agents is as follows:

[0058]

[0059] R1-R5 contains only one -OH group, and the rest contain -H or organic groups that do not contain active hydrogen. Alternatively, R1-R5 contains only one phenolic hydroxyl group, and the rest contain -H or organic groups that do not contain active hydrogen.

[0060] The structural formula of dicarboxylic acid curing agents is as follows:

[0061] HOOC-R6·COOH

[0062] R6: An organic group that does not contain active hydrogen.

[0063] The structural formula of the diimine curing agent is as follows:

[0064]

[0065] R7-R8: Organic groups that do not contain active hydrogen; R8 and R9 cannot be -H.

[0066] The structural formula of the dithiol-based curing agent is as follows:

[0067]

[0068] R 10 Organic groups that do not contain active hydrogen.

[0069] Specifically, the first curing agent is selected from at least one of bisphenol A, hydroquinone and 4,4'-biphenyl, sebacic acid, terephthalic acid, 4,4'-bis-sec-butylaminodiphenylmethane, 4,4'-diacetamidodiphenylmethane, 2-dimercaptoethyl sulfide, and 2,2'-(1,2-ethylenedioxy)diethyl mercaptan.

[0070] In some embodiments of this application, the amine curing agent with ≥3 active hydrogens includes at least one of linear aliphatic amines, alicyclic amines, and aromatic amines.

[0071] Specifically, the amine curing agent with ≥3 active hydrogens is selected from at least one of 4,4'-diaminodiphenylmethane, triethylenetetramine, isophorone diamine, 4,4'-diaminodiphenyl sulfone, polyetheramine, polyesteramine, 4,4'-oxodiphenylamine, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine.

[0072] In some embodiments of this application, the thiol-based curing agent with ≥3 active hydrogens includes at least one of linear aliphatic thiol, alicyclic thiol, and aromatic thiol.

[0073] Specifically, the mercapto-based curing agent with ≥3 active hydrogens is selected from at least one of trimethylolpropane tris(2-mercaptoacetate), pentaerythritol tetramercaptoacetate, tetramercaptobenzene, p-mercaptoterephthalic acid, hexamercaptotriethylene, tris[2-(3-mercaptopropionic acid)ethyl]isocyanuric acid, 2,3-dimercaptosuccinic acid, trimercaptotriazine, and 6-pentaerythritol tetra(3-mercaptobutyrate).

[0074] In some embodiments of this application, the anhydride curing agent includes at least one of aromatic anhydrides, alicyclic anhydrides, or linear aliphatic anhydrides.

[0075] Specifically, the anhydride curing agent is selected from at least one of methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, 2,2-dimethylglutaric anhydride, 2,3-dimethylsuccinic anhydride, glutaric anhydride, succinic anhydride, triphenylhexacarboxylic anhydride, 4,4'-biphenyl ether dianhydride, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, and methylnadic anhydride.

[0076] In some embodiments of this application, the mass parts of each component of the epoxy resin composition are as follows:

[0077] Epoxy resin: 100 parts;

[0078] First curing agent: 1-20 parts;

[0079] When the second curing agent is an amine with ≥3 active hydrogens or a mercapto-based curing agent with ≥3 active hydrogens, the mass fraction of the second curing agent is Cg[ab / 100-2e / f] / h, where a is the mass fraction of epoxy resin (in g), b is the epoxy value of epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), h is the number of active hydrogens contained in the second curing agent, g is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2;

[0080] When the second curing agent is an anhydride-based curing agent, the mass fraction of the second curing agent is Ck[ab / 100-2e / f] / j, where a is the mass fraction of epoxy resin (in g), b is the epoxy value of epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), j is the number of anhydride groups contained in the second curing agent, k is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2.

[0081] For example, the first curing agent is 1 part, 3 parts, 6 parts, 9 parts, 12 parts, 15 parts, 18 parts, or 20 parts.

[0082] In some embodiments, the epoxy resin is a first epoxy resin and a second epoxy resin, wherein the first epoxy resin is selected from one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin, and the second epoxy resin is selected from one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin.

[0083] In some embodiments, the epoxy values ​​of the first epoxy resin and the second epoxy resin are 0.2-0.9 mol / 100g, and the epoxy value of the first epoxy resin is less than that of the second epoxy resin.

[0084] In some embodiments, the mass parts of each component of the epoxy resin composition are as follows:

[0085] First epoxy resin: 70-100 parts;

[0086] Second epoxy resin: 1-30 parts;

[0087] First curing agent: 1-20 parts;

[0088] When the second curing agent is an amine with ≥3 active hydrogens or a mercapto-based curing agent with ≥3 active hydrogens, the mass fraction of the second curing agent is Cg[(ab+cd) / 100-2e / f] / h, where a is the mass fraction of the first epoxy resin (in g), b is the epoxy value of the first epoxy resin (in mol / 100g), c is the mass fraction of the second epoxy resin (in g), d is the epoxy value of the second epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), h is the number of active hydrogens contained in the second curing agent, g is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2;

[0089] When the second curing agent is an anhydride-based curing agent, the mass fraction of the second curing agent is Ck[(ab+cd) / 100-2e / f] / j, where a is the mass fraction of the first epoxy resin (in g), b is the epoxy value of the first epoxy resin (in mol / 100g), c is the mass fraction of the second epoxy resin (in g), d is the epoxy value of the second epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (in g / mol), j is the number of anhydride groups contained in the second curing agent, k is the molar mass of the second curing agent (in g / mol), and C is a correction factor, 0.8≤C≤1.2.

[0090] For example, the first epoxy resin is 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, and 100 parts; the second epoxy resin is 1 part, 3 parts, 6 parts, 9 parts, 12 parts, 15 parts, 18 parts, 21 parts, 24 parts, 27 parts, and 30 parts; and the first curing agent is 1 part, 2 parts, 4 parts, 6 parts, 8 parts, 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, and 20 parts.

[0091] The epoxy resin comprises a first epoxy resin and a second epoxy resin, both with epoxy values ​​of 0.2-0.9 mol / 100g. The epoxy value of the first epoxy resin is lower than that of the second epoxy resin. The mass ratios of the first and second epoxy resins are also specified, with the first epoxy resin comprising 70-100 parts and the second epoxy resin comprising 1-30 parts. Because the average chain length of the second epoxy resin is shorter than that of the first epoxy resin, the crosslinking density in the cured region of the second epoxy resin is greater than that in the cured region of the first epoxy resin. Therefore, through the curing of the two-component epoxy resin, a soft-encapsulated-hard interpenetrating crosslinked network structure can be obtained. This network structure can further improve the heat resistance and Tg of the first epoxy resin.

[0092] In some embodiments, the epoxy resin composition further includes 1-350 parts of filler, the filler including at least one selected from alumina, silica powder, silica, magnesium oxide, boron nitride, kaolin and zinc oxide.

[0093] Adding appropriate fillers to epoxy curing systems can reduce costs, suppress exothermic reactions, extend the pot life of resin compositions, reduce the shrinkage and coefficient of thermal expansion of cured products, improve the heat resistance and flexural strength of cured products, and enhance the arc resistance, tracking resistance, and high-temperature dielectric properties of cured products. The fillers used in this invention are known fillers in epoxy electrical insulation materials, including at least one selected from alumina, silica powder, silica, magnesium oxide, boron nitride, kaolin, and zinc oxide. The average particle diameter of the filler is preferably 1–100 micrometers, more preferably 5–70 micrometers.

[0094] In a second aspect, the present invention provides a method for preparing the above-mentioned epoxy resin composition, the method comprising the preparation of component A and component B;

[0095] The preparation method of component A includes: mixing epoxy resin evenly and degassing it under vacuum under certain conditions to obtain component A;

[0096] The preparation method of component B includes: mixing the first curing agent and the second curing agent evenly, and then dehydrating and degassing them under vacuum under certain conditions to obtain component B;

[0097] Component A and component B are mixed, injected into a mold, and cured under certain conditions to obtain an epoxy resin composition.

[0098] In some embodiments, if the epoxy resin is a first epoxy resin and a second epoxy resin, the preparation method of component A includes: mixing the first epoxy resin and the second epoxy resin evenly, and degassing under vacuum under certain conditions to obtain component A.

[0099] Alternatively, the preparation method of component A includes: mixing the first epoxy resin and the second epoxy resin evenly, dehydrating and degassing the filler under certain conditions, and adding the pretreated filler to the resin mixture to obtain component A;

[0100] Alternatively, the preparation method of component B includes: mixing the first curing agent and the second curing agent evenly, and dehydrating and degassing them under certain conditions to obtain component B.

[0101] Specifically, the preparation method of component A includes: drying and degassing epoxy resin for more than 3 hours at a vacuum environment of 80℃~120℃ and a vacuum degree not exceeding 3500Pa to obtain component A;

[0102] The preparation method of component B includes: mixing the first curing agent and the second curing agent evenly, and degassing and dehydrating the mixture of the first curing agent and the second curing agent in a vacuum environment of 50℃~90℃ and a vacuum degree not higher than 5000Pa to obtain component B;

[0103] Component A and component B are mixed and injected into a mold. The mixture is then cured at 80℃ to 180℃ and under a vacuum of no more than 5000Pa to obtain an epoxy resin composition.

[0104] In a third aspect, the present invention provides an epoxy resin composition for the preparation of insulating components in electronic and electrical equipment.

[0105] The present invention will be further described in detail below with reference to specific embodiments.

[0106] Information on the raw materials involved in the specific implementation method is shown in Table 1:

[0107] Table 1 Information on raw materials for epoxy resin compositions in the examples and comparative examples.

[0108]

[0109]

[0110] Example 1

[0111] Please refer to Tables 1 and 2. The epoxy resin composition of this embodiment includes the following raw materials in parts by weight:

[0112] Bisphenol A type epoxy resin 2: 100 parts;

[0113] First curing agent: Bisphenol A: 1 part;

[0114] Second curing agent 4,4'-diaminodiphenylmethane: 24 parts;

[0115] Filler: 300 parts.

[0116] The preparation method of this epoxy resin composition is as follows:

[0117] The preparation method of component A includes: drying and degassing bisphenol A type epoxy resin 2 for more than 3 hours in a vacuum environment of 80℃~120℃ and vacuum degree not higher than 3500Pa to obtain component A;

[0118] The preparation method of component B includes: mixing the first curing agent bisphenol A and the second curing agent 4,4'-diaminodiphenylmethane evenly, and degassing and dehydrating the mixture of the first curing agent and the second curing agent in a vacuum environment of 50℃~90℃ and a vacuum degree not higher than 5000Pa to obtain component B;

[0119] Component A and component B are mixed and injected into a mold. The mixture is then cured at 100℃~180℃ and under a vacuum degree not exceeding 5000Pa to obtain an epoxy resin composition.

[0120] Example 2

[0121] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except for the proportions of each component. Please refer to Tables 1 and 2 for details.

[0122] Bisphenol A type epoxy resin 2: 100 parts;

[0123] First curing agent: Bisphenol A: 10 parts;

[0124] Second curing agent 4,4'-diaminodiphenylmethane: 16 parts;

[0125] Filler: 300 parts.

[0126] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the proportions of each raw material component are different. Please refer to Table 2.

[0127] Example 3

[0128] The raw material formulation for preparing the epoxy resin composition in this embodiment is basically the same as that in Example 1, except for the proportions of each component, as shown in Table 2:

[0129] Bisphenol A type epoxy resin 2: 100 parts;

[0130] First curing agent: Bisphenol A: 20 parts;

[0131] Second curing agent 4,4'-diaminodiphenylmethane: 7 parts;

[0132] Filler: 300 parts.

[0133] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the proportions of each raw material component are different. Please refer to Table 2.

[0134] Example 4

[0135] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and proportion of each component are shown in Tables 1 and 2.

[0136] Bisphenol A type epoxy resin 1:100 parts;

[0137] First curing agent: terephthalic acid: 10 parts;

[0138] Second curing agent 4,4'-diaminodiphenylmethane: 6 parts;

[0139] Filler: 300 parts.

[0140] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0141] Example 5

[0142] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and proportion of each component are shown in Tables 1 and 2.

[0143] Bisphenol A type epoxy resin 1:100 parts;

[0144] First curing agent: 4,4'-bis-sec-butylaminodiphenylmethane: 10 parts;

[0145] Second curing agent 4,4'-diaminodiphenylmethane: 9 parts;

[0146] Filler: 300 parts.

[0147] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0148] Example 6

[0149] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and proportion of each component are shown in Tables 1 and 2.

[0150] Bisphenol A type epoxy resin 1:100 parts;

[0151] First curing agent: Bisphenol A: 10 parts;

[0152] Second curing agent: trimethylolpropane tris(2-mercaptoacetic acid): 8 parts;

[0153] Filler: 300 parts.

[0154] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0155] Example 7

[0156] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and proportion of each component are shown in Tables 1 and 2.

[0157] Bisphenol A type epoxy resin 1:100 parts;

[0158] First curing agent: Bisphenol A: 10 parts;

[0159] Second curing agent: methyltetrahydrophthalic anhydride: 9.5 parts;

[0160] Filler: 300 parts.

[0161] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0162] Example 8

[0163] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and proportion of each component are shown in Tables 1 and 2.

[0164] Bisphenol A type epoxy resin 1:100 parts;

[0165] First curing agent: Bisphenol A: 10 parts;

[0166] Second curing agent: methyltetrahydrophthalic anhydride: 13 parts;

[0167] Filler: 300 parts.

[0168] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0169] Example 9

[0170] The formulation of the epoxy resin composition in this embodiment is basically the same as that in Example 1, except that the composition and proportion of each component are shown in Tables 1 and 2.

[0171] Bisphenol A type epoxy resin 1:70 parts;

[0172] Bisphenol A type epoxy resin 3:30 parts;

[0173] First curing agent: Bisphenol A: 10 parts;

[0174] Second curing agent: methyltetrahydrophthalic anhydride: 21 parts;

[0175] Filler: 300 parts.

[0176] The preparation method of this epoxy resin composition is as follows:

[0177] The preparation method of component A includes: drying and degassing bisphenol A type epoxy resin 1 and bisphenol A type epoxy resin 3 for more than 3 hours in a vacuum environment of 80℃~120℃ and vacuum degree not higher than 3500Pa to obtain component A.

[0178] The preparation method of component B includes: mixing the first curing agent bisphenol A and the second curing agent methyltetrahydrophthalic anhydride evenly, and degassing and dehydrating the mixture of the first curing agent and the second curing agent in a vacuum environment of 50℃~90℃ and a vacuum degree not higher than 5000Pa to obtain component B;

[0179] Component A and component B are mixed and injected into a mold. The mixture is then cured at 100℃~180℃ and under a vacuum degree not exceeding 5000Pa to obtain an epoxy resin composition.

[0180] Example 10

[0181] The raw material formulation for preparing the epoxy resin composition in this embodiment is basically the same as that in Example 9, except that the composition and proportion of each component are shown in Tables 1 and 2:

[0182] Bisphenol A type epoxy resin 1:90 parts;

[0183] Alicyclic epoxy resin: 10 parts;

[0184] First curing agent: Bisphenol A: 10 parts;

[0185] Second curing agent: methyltetrahydrophthalic anhydride: 19 parts;

[0186] Filler: 300 parts.

[0187] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 9, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0188] Example 11

[0189] The raw material formulation for preparing the epoxy resin composition in this embodiment is basically the same as that in Example 9, except that the composition and proportion of each component are shown in Tables 1 and 2:

[0190] Bisphenol A type epoxy resin 1:85 parts;

[0191] Bisphenol A type epoxy resin 3:15 parts;

[0192] First curing agent: Bisphenol A: 10 parts;

[0193] Second curing agent: methyltetrahydrophthalic anhydride: 16 parts;

[0194] Filler: 300 parts.

[0195] The preparation method of the epoxy resin composition in this embodiment is basically the same as that in Example 9, except that the composition and quantity of each raw material component are different. Please refer to Table 2.

[0196] Comparative Example 1

[0197] The raw material formulation for preparing the epoxy resin composition in this comparative example is basically the same as that in Example 1, except for the proportions of each component, as shown in Tables 1 and 2:

[0198] Bisphenol A type epoxy resin 2: 100 parts;

[0199] First curing agent: Bisphenol A: 26 parts;

[0200] Filler: 300 parts.

[0201] The preparation method of the epoxy resin composition in this comparative example is basically the same as that in Example 1, except that the proportions of each raw material component are different. Please refer to Table 2.

[0202] Comparative Example 2

[0203] The raw material formulation for preparing the epoxy resin composition in this comparative example is basically the same as that in Example 1, except for the proportions of each component, as shown in Tables 1 and 2:

[0204] Bisphenol A type epoxy resin 2: 100 parts;

[0205] Second curing agent 4,4'-diaminodiphenylmethane: 26 parts;

[0206] Filler: 300 parts.

[0207] The preparation method of the epoxy resin composition in this comparative example is basically the same as that in Example 1, except that the proportions of each raw material component are different. Please refer to Table 2.

[0208] Comparative Example 3

[0209] The raw material formulation for preparing the epoxy resin composition in this comparative example is basically the same as that in Example 9, except for the proportions of each component, as shown in Tables 1 and 2:

[0210] Bisphenol A type epoxy resin 1:60 parts;

[0211] Bisphenol A type epoxy resin 2:40 parts;

[0212] First curing agent: Bisphenol A: 10 parts;

[0213] Second curing agent: 4,4'-diaminodiphenylmethane: 9 parts;

[0214] Filler: 300 parts.

[0215] The preparation method of the epoxy resin composition in this comparative example is basically the same as that in Example 9, except that the proportions of each raw material component are different. Please refer to Table 2.

[0216] The test standards for the properties of the epoxy resin compositions obtained in the above embodiments and comparative examples are as follows:

[0217] (1) Breakdown strength test

[0218] The test was conducted using a power frequency test transformer (power frequency voltage measurement system) according to the method specified in GB / T 1408—2016. The test temperature was 23±2℃. For the electrical performance test, samples with a diameter of 100mm and a thickness of 1mm were used. To prevent surface flashover, the samples and electrodes were immersed in dimethyl silicone oil. During the test, the voltage rise rate was controlled at 1kV / s, and the average value was taken.

[0219] (2) Dielectric property testing

[0220] The tests were conducted according to the method specified in 7.3 of GB 1409-2006, at a test temperature of 23±2℃. The relative permittivity and dielectric loss of the samples at room temperature were measured using a broadband dielectric spectrometer. The test frequency range was 10... -1 ~10 6 Hz. Five samples were tested, and the average value was taken.

[0221] (3) Tensile test

[0222] The test was conducted according to Clause 9 of GB 1040—2008, with a test temperature of 23±2℃. The tensile test used a standard dumbbell-shaped specimen with a tensile speed of 2 mm / min. The tensile strength and elongation at break of five specimens were tested using a micro-controlled electronic universal tensile testing machine from Dongguan High-Speed ​​Railway Testing Co., Ltd., and the average value of the results was taken.

[0223] (4) Glass transition temperature test

[0224] Differential scanning calorimetry (DSC) was performed using a Netzsch differential scanning calorimeter from Germany. The sample mass was approximately 5-10 mg, the test temperature range was 30–180 °C, the heating rate was 10 K / min, and the test atmosphere was nitrogen with a flow rate of 20 mL / min.

[0225] (5) Thermal stability performance test

[0226] Thermogravimetric analysis (TGA) was performed using a Netzsch thermogravimetric analyzer from Germany. The sample was approximately 5-10 mg, and the test was conducted in a nitrogen atmosphere with a flow rate of 20 mL / min. The temperature range was 50-700 °C, and the heating rate was 10 K / min.

[0227] (6) Impact performance test

[0228] Impact strength shall be measured using an automated digital IZOD impact tester (Guangdong, Guangce) in accordance with GB / T 1843-2008.

[0229] See Table 3 for the test results of the epoxy resin compositions GJB7279-2011 prepared in the examples and comparative examples.

[0230] Table 2 Examples and Comparative Formulations of Epoxy Resin Compositions

[0231]

[0232]

[0233]

[0234] Table 3. Test results of epoxy resin compositions (GJB7279-2011) prepared in the examples and comparative examples.

[0235]

[0236]

[0237] Table 3 shows that the glass transition temperatures (Tg) of the epoxy resin compositions prepared in Examples 1 to 11 are all greater than 120℃, indicating a wide applicable temperature range. They also exhibit good thermal stability, with a 5% mass loss temperature (Tg) under specific conditions. d5％ All temperatures were above 350℃, and Tmax was above 380℃. At 700℃, the percentage of residual carbon after pyrolysis (RCY700℃ wt%) was above 70%. Dielectric properties, such as dielectric constant and dielectric loss, were good. The breakdown strength of Examples 1 to 6 was above 12KV / mm, and the breakdown strength of Examples 7 to 11 was above 30KV / mm. Tensile strength and elongation at break were both improved. The impact strength of Examples 1 to 3 was above 6KJ / m. 2 The impact strength of Examples 4-11 is greater than 10 KJ / m. 2 It has good crack resistance.

[0238] Comparative Example 1 did not add a second curing agent, and the resulting epoxy resin composition had a long-chain structure. Compared with the 3D network crosslinked structure of the epoxy resin composition in Example 2, the glass transition temperature Tg, dielectric properties, breakdown strength, tensile strength, elongation at break, and impact strength were all significantly reduced.

[0239] Comparative Example 2 did not add a first curing agent. Although the epoxy resin composition prepared was also a network structure, Comparative Example 2 lacked a first curing agent that was more rigid than the main chain structure of epoxy resin. Therefore, compared with Example 2, the epoxy resin composition prepared in Comparative Example 2 showed a decreasing trend in glass transition temperature Tg, dielectric properties, breakdown strength, tensile strength, elongation at break, and impact strength.

[0240] Although Comparative Example 3 uses two curing agents, the first epoxy resin has too few parts by mass and the second epoxy resin has too many parts by mass, making it difficult to mix the two resins evenly during the mixing process. Defects are easily generated inside the interpenetrating network structure after curing. As a result, the epoxy resin composition prepared in Comparative Example 3 shows a decreasing trend in glass transition temperature Tg, dielectric properties, breakdown strength, tensile strength, elongation at break, and impact strength compared with Example 2.

[0241] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. An epoxy resin composition, characterized in that, The product comprises component A and component B; component A comprises epoxy resin; component B comprises a first curing agent and a second curing agent; the first curing agent is a curing agent containing two active hydrogen atoms, and the first curing agent includes at least one of bisphenol hydroxyl curing agents, biscarboxyl curing agents, bisimine curing agents, bisthiol curing agents, or curing agents containing any two of the following groups: phenolic hydroxyl, thiol, carboxyl, and imine; the second curing agent is selected from one of the following: amine curing agents with ≥3 active hydrogen atoms, thiol curing agents with ≥3 active hydrogen atoms, or acid anhydride curing agents.

2. The epoxy resin composition according to claim 1, characterized in that, The epoxy resin includes at least one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin.

3. The epoxy resin composition according to claim 1, characterized in that, The first curing agent is selected from at least one of bisphenol A, hydroquinone and 4,4'-biphenyl, sebacic acid, terephthalic acid, 4,4'-bis-sec-butylaminodiphenylmethane, 4,4'-diacetamidodiphenylmethane, 2-dimercaptoethyl sulfide, and 2,2'-(1,2-ethylenedioxy)diethyl mercaptan.

4. The epoxy resin composition according to claim 1, characterized in that, The amine curing agent with ≥3 active hydrogens includes at least one of linear aliphatic amines, alicyclic amines, and aromatic amines.

5. The epoxy resin composition according to claim 1, characterized in that, The thiol-based curing agent with ≥3 active hydrogens includes at least one of linear aliphatic thiol, alicyclic thiol, and aromatic thiol.

6. The epoxy resin composition according to claim 1, characterized in that, The anhydride curing agent includes at least one of aromatic anhydrides, alicyclic anhydrides, or linear aliphatic anhydrides.

7. The epoxy resin composition according to claim 4, characterized in that, The amine curing agent with ≥3 active hydrogen atoms is selected from at least one of 4,4'-diaminodiphenylmethane, triethylenetetramine, isophorone diamine, 4,4'-diaminodiphenyl sulfone, polyetheramine, polyesteramine, 4,4'-oxodiphenylamine, 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane, m-phenylenediamine, o-phenylenediamine, and p-phenylenediamine.

8. The epoxy resin composition according to claim 5, characterized in that, The thiol-based curing agent with ≥3 active hydrogens is selected from at least one of trimethylolpropane tris(2-mercaptoacetate), pentaerythritol tetramercaptoacetate, tetramercaptobenzene, p-mercaptoterephthalic acid, hexamercaptotriethylene, tris[2-(3-mercaptopropionic acid)ethyl]isocyanuric acid, 2,3-dimercaptosuccinic acid, trimercaptotriazine, and 6-pentaerythritol tetra(3-mercaptobutyrate).

9. The epoxy resin composition according to claim 6, characterized in that, The anhydride curing agent is selected from at least one of methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, 2,2-dimethylglutaric anhydride, 2,3-dimethylsuccinic anhydride, glutaric anhydride, succinic anhydride, triphenylhexacarboxylic anhydride, 4,4'-biphenyl ether dianhydride, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, and methylnadic anhydride.

10. The epoxy resin composition according to claim 1, characterized in that, The mass parts of each component in the epoxy resin composition are as follows: epoxy resin: 100 parts; first curing agent: 1-20 parts; when the second curing agent is an amine with ≥3 active hydrogens or a mercapto-based curing agent with ≥3 active hydrogens, the mass parts of the second curing agent are... Where a is the mass fraction of epoxy resin (in g), b is the epoxy value of epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), h is the amount of active hydrogen contained in the second curing agent, g is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2; when the second curing agent is an anhydride-based curing agent, the mass fraction of the second curing agent is... Where a is the mass fraction of epoxy resin (in g), b is the epoxy value of epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), j is the number of anhydride groups in the second curing agent, k is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.

2.

11. The epoxy resin composition according to claim 1, characterized in that, The epoxy resin is a first epoxy resin and a second epoxy resin. The first epoxy resin is selected from one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin. The second epoxy resin is selected from one of bisphenol A type epoxy resin, alicyclic epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and aliphatic epoxy resin.

12. The epoxy resin composition according to claim 11, characterized in that, The epoxy values ​​of the first epoxy resin and the second epoxy resin are 0.2-0.9 mol / 100g, and the epoxy value of the first epoxy resin is less than that of the second epoxy resin.

13. The epoxy resin composition according to claim 12, characterized in that, The mass parts of each component in the epoxy resin composition are as follows: First epoxy resin: 70-100 parts; Second epoxy resin: 1-30 parts; First curing agent: 1-20 parts; When the second curing agent is an amine with ≥3 active hydrogens or a mercapto-based curing agent with ≥3 active hydrogens, the mass part of the second curing agent is... Where, a is the mass fraction of the first epoxy resin (in g), b is the epoxy value of the first epoxy resin (in mol / 100g), c is the mass fraction of the second epoxy resin (in g), d is the epoxy value of the second epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), h is the amount of active hydrogen contained in the second curing agent, g is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.2; when the second curing agent is an anhydride-based curing agent, the mass fraction of the second curing agent is... Where, a is the mass fraction of the first epoxy resin (in g), b is the epoxy value of the first epoxy resin (in mol / 100g), c is the mass fraction of the second epoxy resin (in g), d is the epoxy value of the second epoxy resin (in mol / 100g), e is the mass fraction of the first curing agent (in g), f is the molar mass of the first curing agent (g / mol), j is the number of anhydride groups contained in the second curing agent, k is the molar mass of the second curing agent (g / mol), and C is a correction factor, 0.8≤C≤1.

2.

14. The epoxy resin composition according to claim 1, characterized in that, The epoxy resin composition further includes 1-350 parts of filler, wherein the filler includes at least one selected from alumina, silica powder, silica, magnesium oxide, boron nitride, kaolin and zinc oxide.

15. A method for preparing an epoxy resin composition according to any one of claims 1-14, characterized in that, The preparation method includes the preparation of component A and the preparation of component B; The preparation method of component A includes: mixing epoxy resin evenly and degassing under vacuum under certain conditions to obtain component A; the preparation method of component B includes: mixing the first curing agent and the second curing agent evenly and dehydrating and degassing under vacuum under certain conditions to obtain component B; mixing component A and component B, injecting into a mold, and curing under certain conditions to obtain the epoxy resin composition.

16. The method for preparing the epoxy resin composition according to claim 15, characterized in that, If the epoxy resin is the first epoxy resin and the second epoxy resin, the preparation method of component A includes: mixing the first epoxy resin and the second epoxy resin evenly, and degassing under vacuum under certain conditions to obtain component A; or, the preparation method of component A includes: mixing the first epoxy resin and the second epoxy resin evenly, dehydrating and degassing the filler under certain conditions, and adding the pretreated filler to the resin mixture to obtain component A; or, the preparation method of component B includes: mixing the first curing agent and the second curing agent evenly, and dehydrating and degassing under certain conditions to obtain component B.

17. The use of an epoxy resin composition as described in any one of claims 1-14 in an insulating component of an electronic or electrical device.

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