High-temperature-resistant epoxy resin packaging material and preparation method thereof

Abstract

The invention belongs to the technical field of packaging materials, and particularly relates to a high-temperature-resistant epoxy resin packaging material and a preparation method thereof. The high-temperature-resistant epoxy resin packaging material is prepared from components in parts by mass as follows: 7-10 parts of epoxy resin, 3-6 parts of triglycidyl p-aminophenol, 3-8 parts of a curing agent, 1-2 parts of a curing accelerator, 80-90 parts of filler and 1-3 parts of a coupling agent. The high-temperature-resistant epoxy resin packaging material prepared by the invention has excellent high temperature resistance, high tensile strength and strong copper substrate adhesion performance.

Description

Technical Field

[0001] This invention belongs to the field of encapsulation materials technology, specifically relating to a high-temperature resistant epoxy resin encapsulation material and its preparation method. Background Technology

[0002] In the field of new energy vehicles, with the rapid development of electrification technology, power semiconductor devices (such as IGBTs and SiC modules), as core components of motor drive systems, are facing increasingly harsh operating environments. These devices not only need to withstand high voltage and high current during operation, but also face complex conditions such as high temperatures in the engine compartment, severe temperature cycling, and long-term vibration. Especially under conditions of vehicle acceleration, braking, or high-temperature weather, the operating temperature of power chips can rapidly rise to over 180°C, with local hotspots even exceeding 200°C.

[0003] Traditional epoxy resin encapsulation materials exhibit significant defects in this application scenario. Under continuous high temperatures and thermal cycling, they are prone to thermal aging, leading to material embrittlement and cracking, loss of chip protection, and severely impacting the long-term reliability of the device. Simultaneously, the material's tensile strength is low, making it difficult to resist the risk of crack formation and propagation caused by mechanical impact or vibration. More critically, traditional epoxy resin exhibits poor adhesion to copper substrates (commonly used in DBC substrates for power modules), easily leading to interface delamination, compromising the integrity of the encapsulation structure, and becoming one of the main causes of device failure.

[0004] In the prior art, in order to improve the high temperature resistance of epoxy resin encapsulation materials, the common method is to increase the glass transition temperature (Tg) of the material by using multifunctional epoxy resin. However, this is often accompanied by a significant negative effect: a decrease in the tensile strength of the material.

[0005] Therefore, in the packaging of power modules for new energy vehicles, there is an urgent need for a new type of epoxy packaging material that combines excellent high temperature resistance and high tensile strength to ensure the long-term stable operation and high reliability of electronic devices under extreme conditions. Summary of the Invention

[0006] The purpose of this invention is to provide a high-temperature resistant epoxy resin encapsulation material and its preparation method.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A high-temperature resistant epoxy resin encapsulation material comprises the following components in parts by weight: 7-10 parts epoxy resin, 3-6 parts triglycidyl-p-aminophenol, 3-8 parts curing agent, 1-2 parts curing accelerator, 80-90 parts filler, and 1-3 parts coupling agent.

[0008] Preferably, the mass ratio of 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer, 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl)adipate is (1.3-1.5):(0.9-1.1):(0.2-0.4).

[0009] Preferably, the 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer is sourced from Jiangsu Taitel New Material Technology Co., Ltd., model TTA-34.

[0010] Preferably, the 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester has an epoxy equivalent of 125-135 g / mol, a viscosity of 220-300 mPa·s at 25°C, and a product model of T-2103P, originating from Changzhou Hongyu Chemical Co., Ltd.

[0011] Preferably, the bis((3,4-epoxycyclohexyl)methyl)adipate has an epoxy equivalent of 190-210 g / mol, a viscosity of 500-650 mPa·s at 25°C, and is product model TTA26, sourced from Jiangsu Taitel New Material Technology Co., Ltd.

[0012] This invention improves the glass transition temperature of high-temperature epoxy resin encapsulation materials and enhances adhesion to copper substrates by compounding three epoxy resins. Analysis shows that the 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer provides a rigid framework, which, when compounded with the other two components, achieves three-dimensional cross-linked network reinforcement, thereby increasing the glass transition temperature of the encapsulation material. Simultaneously, the appropriate addition of flexible aliphatic chain bridging epoxy groups can release interfacial stress and improve adhesion.

[0013] The preferred product is triglycidyl-p-aminophenol, sourced from Jiangsu Taiter New Material Technology Co., Ltd., model TTA500.

[0014] This invention improves the tensile strength of encapsulation materials by compounding triglycidyl-p-aminophenol and epoxy resin. Analysis shows that the synergistic effect of triglycidyl-p-aminophenol and epoxy resin forms a highly branched network, increasing molecular chain entanglement and thus improving tensile strength.

[0015] Preferably, the curing agent is selected from at least one of m-phenylenediamine, diaminodiphenylmethane, benzophenone tetracarboxylic anhydride, and methylhexahydrophthalic anhydride.

[0016] The curing agent selected in this invention can increase the glass transition temperature of high-temperature epoxy resin encapsulation materials, while also improving aging resistance. In particular, when the curing agent is diaminodiphenylmethane, the diphenylmethane backbone and active hydrogen form high-density CN crosslinks with the epoxy groups, thereby increasing both the glass transition temperature and aging resistance.

[0017] Preferably, the curing accelerator is selected from at least one of tris(dimethylaminomethyl)phenol and 2,2-(dimethylaminomethyl)phenol.

[0018] Preferably, the coupling agent is selected from at least one of silane coupling agents KH550, KH560, and KH580.

[0019] Preferably, the filler is 325-mesh fused silica powder with a silica content of 99.95 wt%, manufactured by Jiangsu Haosen New Material Technology Co., Ltd., and model number HS-RG18.

[0020] This invention provides a method for preparing a high-temperature resistant epoxy resin encapsulation material, comprising the following steps: mixing aliphatic epoxy resin and triglycidyl-p-aminophenol, stirring until homogeneous, continuing to add a curing agent and a curing accelerator, and ensuring complete dissolution; finally adding filler and coupling agent, and stirring until homogeneous; and evacuating to a vacuum. 0.1 MPa, maintain for 10 min, add to screw extruder for mixing and extrusion, feeding section 40-50℃, melt mixing section 70-80℃, homogenization section 85-90℃, die head extrusion section 60-65℃, to obtain high temperature resistant epoxy resin encapsulation material.

[0021] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: 1. This invention provides a high-temperature resistant epoxy resin encapsulation material and its preparation method. Through precise component design and synergistic mechanism, the high-temperature resistance, adhesion and mechanical properties are improved simultaneously.

[0022] 2. This invention improves the glass transition temperature of high-temperature epoxy resin encapsulation materials by compounding three types of epoxy resins, and at the same time improves the adhesion of copper substrates.

[0023] 3. In the system of the present invention, the tensile strength of the encapsulation material is improved by compounding triglycidyl-p-aminophenol and epoxy resin.

[0024] 4. The curing agent selected in this invention can increase the glass transition temperature of the high-temperature epoxy resin encapsulation material and improve its aging resistance. Detailed Implementation

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0026] Example 1 This embodiment provides a high-temperature resistant epoxy resin encapsulation material, comprising the following components in parts by weight: 8 parts epoxy resin, 5 parts triglycidyl-p-aminophenol, 6 parts curing agent, 1.4 parts curing accelerator, 86 parts filler, and 2 parts coupling agent.

[0027] The epoxy resin includes 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer in a mass ratio of 1.4:1:0.3, 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl)adipate.

[0028] The 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer is sourced from Jiangsu Taitel New Material Technology Co., Ltd., model TTA-34.

[0029] The 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester has an epoxy equivalent of 125-135 g / mol, a viscosity of 220-300 mPa·s at 25°C, and is product model T-2103P, sourced from Changzhou Hongyu Chemical Co., Ltd.

[0030] The bis((3,4-epoxycyclohexyl)methyl)adipate has an epoxy equivalent of 190-210 g / mol and a viscosity of 500-650 mPa·s at 25°C. The product model is TTA26 and it is sourced from Jiangsu Taiter New Material Technology Co., Ltd.

[0031] Triglycidyl-p-aminophenol, sourced from Jiangsu Taiter New Material Technology Co., Ltd., model TTA500.

[0032] The curing agent is diaminodiphenylmethane. The curing accelerator is tris(dimethylaminomethyl)phenol. The coupling agent is silane coupling agent KH550. The filler is 325-mesh fused silica powder with a silica content of 99.95 wt%, manufactured by Jiangsu Haosen New Material Technology Co., Ltd., specification HS-RG18.

[0033] The preparation method of the high-temperature resistant epoxy resin encapsulation material includes the following steps: mixing aliphatic epoxy resin and triglycidyl-p-aminophenol, stirring until uniformly mixed, continuing to add curing agent and curing accelerator, and ensuring complete dissolution; finally adding filler and coupling agent, and stirring until uniform; and evacuating to... 0.1 MPa, maintained for 10 min, added to the screw extruder for mixing and extrusion, feeding section 45℃, melt mixing section 75℃, homogenization section 90℃, die head extrusion section 65℃, to obtain high temperature resistant epoxy resin encapsulation material.

[0034] Example 2 This embodiment provides a high-temperature resistant epoxy resin encapsulation material, comprising the following components in parts by weight: 7 parts epoxy resin, 6 parts triglycidyl-p-aminophenol, 3 parts curing agent, 2 parts curing accelerator, 80 parts filler, and 3 parts coupling agent.

[0035] The epoxy resin includes 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer in a mass ratio of 1.3:1:0.4, 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl)adipate.

[0036] The 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer is sourced from Jiangsu Taitel New Material Technology Co., Ltd., model TTA-34.

[0037] The 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester has an epoxy equivalent of 125-135 g / mol, a viscosity of 220-300 mPa·s at 25°C, and is product model T-2103P, sourced from Changzhou Hongyu Chemical Co., Ltd.

[0038] The bis((3,4-epoxycyclohexyl)methyl)adipate has an epoxy equivalent of 190-210 g / mol and a viscosity of 500-650 mPa·s at 25°C. The product model is TTA26 and it is sourced from Jiangsu Taiter New Material Technology Co., Ltd.

[0039] Triglycidyl-p-aminophenol, sourced from Jiangsu Taiter New Material Technology Co., Ltd., model TTA500.

[0040] The curing agent is diaminodiphenylmethane. The curing accelerator is tris(dimethylaminomethyl)phenol. The coupling agent is silane coupling agent KH550. The filler is 325-mesh fused silica powder with a silica content of 99.95 wt%, manufactured by Jiangsu Haosen New Material Technology Co., Ltd., specification HS-RG18.

[0041] The preparation method of the high-temperature resistant epoxy resin encapsulation material includes the following steps: mixing aliphatic epoxy resin and triglycidyl-p-aminophenol, stirring until uniformly mixed, continuing to add curing agent and curing accelerator, and ensuring complete dissolution; finally adding filler and coupling agent, and stirring until uniform; and evacuating to... 0.1 MPa, maintained for 10 min, added to the screw extruder for mixing and extrusion, feeding section 45℃, melt mixing section 75℃, homogenization section 90℃, die head extrusion section 65℃, to obtain high temperature resistant epoxy resin encapsulation material.

[0042] Example 3 This embodiment provides a high-temperature resistant epoxy resin encapsulation material, comprising the following components in parts by weight: 10 parts epoxy resin, 3 parts triglycidyl-p-aminophenol, 8 parts curing agent, 1 part curing accelerator, 90 parts filler, and 1 part coupling agent.

[0043] The epoxy resin includes 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer in a mass ratio of 1.5:1:0.2, 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl)adipate.

[0044] The 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer is sourced from Jiangsu Taitel New Material Technology Co., Ltd., model TTA-34.

[0045] The 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester has an epoxy equivalent of 125-135 g / mol, a viscosity of 220-300 mPa·s at 25°C, and is product model T-2103P, sourced from Changzhou Hongyu Chemical Co., Ltd.

[0046] The bis((3,4-epoxycyclohexyl)methyl)adipate has an epoxy equivalent of 190-210 g / mol and a viscosity of 500-650 mPa·s at 25°C. The product model is TTA26 and it is sourced from Jiangsu Taiter New Material Technology Co., Ltd.

[0047] Triglycidyl-p-aminophenol, sourced from Jiangsu Taiter New Material Technology Co., Ltd., model TTA500.

[0048] The curing agent is diaminodiphenylmethane. The curing accelerator is tris(dimethylaminomethyl)phenol. The coupling agent is silane coupling agent KH550. The filler is 325-mesh fused silica powder with a silica content of 99.95 wt%, manufactured by Jiangsu Haosen New Material Technology Co., Ltd., specification HS-RG18.

[0049] The preparation method of the high-temperature resistant epoxy resin encapsulation material includes the following steps: mixing aliphatic epoxy resin and triglycidyl-p-aminophenol, stirring until uniformly mixed, continuing to add curing agent and curing accelerator, and ensuring complete dissolution; finally adding filler and coupling agent, and stirring until uniform; and evacuating to... 0.1 MPa, maintained for 10 min, added to the screw extruder for mixing and extrusion, feeding section 45℃, melt mixing section 75℃, homogenization section 90℃, die head extrusion section 65℃, to obtain high temperature resistant epoxy resin encapsulation material.

[0050] Comparative Example 1 The difference between this comparative example and Example 1 is that the total number of epoxy resin and triglycidyl-p-aminophenol remains the same, but 8 parts of epoxy resin and 5 parts of triglycidyl-p-aminophenol are replaced with 13 parts of epoxy resin.

[0051] A high-temperature resistant epoxy resin encapsulation material comprises the following components in parts by weight: 8 parts epoxy resin, 5 parts triglycidyl-p-aminophenol, 6 parts curing agent, 1.4 parts curing accelerator, 86 parts filler, and 2 parts coupling agent.

[0052] Comparative Example 2 The difference between this comparative example and Example 1 is that the total number of epoxy resin and triglycidyl-p-aminophenol remains unchanged, but 8 parts of epoxy resin and 5 parts of triglycidyl-p-aminophenol are replaced with 12 parts of epoxy resin and 1 part of triglycidyl-p-aminophenol.

[0053] Comparative Example 3 The difference between this comparative example and Example 1 is that the 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester has an epoxy equivalent of 125-145 g / mol, a viscosity of 300-450 mPa·s at 25°C, and the product model is T-2103, which is sourced from Changzhou Hongyu Chemical Co., Ltd.

[0054] Comparative Example 4 The difference between this comparative example and Example 1 is that the epoxy resin includes 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer in a mass ratio of 1.4:1, and 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester.

[0055] Comparative Example 5 The difference between this comparative example and Example 1 is that the epoxy resin includes 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer, 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl) adipate in a mass ratio of 1.2:1.2:0.1.

[0056] Comparative Example 6 The difference between this comparative example and Example 1 is that the epoxy resin includes 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer in a mass ratio of 1.6:0.8:0.5, 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl)adipate.

[0057] Comparative Example 7 The difference between this comparative example and Example 1 is that the curing agent is phthalic anhydride.

[0058] Performance testing The epoxy resin encapsulation materials prepared in Examples 1-3 and Comparative Examples 1-7 were subjected to performance tests.

[0059] (1) Glass transition temperature: Refer to GB / T40564 Tested according to the 2021 "Test Methods for Epoxy Molding Compounds for Electronic Packaging"; (2) Tensile strength: Refer to GB / T2567 The 2021 standard specifies a tensile rate of 20 mm / min, and testing is conducted using a universal electronic testing machine.

[0060] (3) Aging resistance: The sample thickness is 0.2 mm. It is placed in a constant temperature and humidity chamber with a temperature of 65±2℃ and a relative humidity of 80±2%. After 6 months of storage, observe whether there is obvious corrosion, yellowing, blistering or cracking. If there is, it is considered unqualified, otherwise it is considered qualified. 80 samples are tested in each group, and the number of qualified samples is counted.

[0061] (4) Adhesion to copper substrate: Refer to GB / T40564 The 2021 "Test Method for Epoxy Molding Compounds for Electronic Packaging" tests the adhesion of the compound to a copper substrate.

[0062] The results are shown in Table 1.

[0063] Table 1 Performance Test Results

[0064] As shown in Table 1, the epoxy resin encapsulation materials of Examples 1-3 have a glass transition temperature higher than 200°C, while maintaining excellent tensile strength, copper substrate adhesion, and aging resistance.

[0065] In Comparative Example 1, the absence of triglycidyl-p-aminophenol (TGAP) resulted in a decrease in crosslinking density, and a significant reduction in glass transition temperature, tensile strength, aging resistance, and adhesion to copper substrates.

[0066] In Comparative Example 2, the reduction of triglycidyl p-aminophenol resulted in an incomplete rigid network, a decrease in the benzene ring conjugated structure, and a decrease in the glass transition temperature.

[0067] In Comparative Example 3, the viscosity of 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester increased, which led to residual micropores after vacuum degassing and a decrease in tensile strength.

[0068] In Comparative Example 4, the removal of bis((3,4-epoxycyclohexyl)methyl)adipate reduced the number of flexible segments in the system, resulting in decreased tensile strength and adhesion to copper substrates.

[0069] The change in the composition ratio of epoxy resin in Comparative Examples 5 and 6 led to uneven cross-linking, resulting in varying degrees of decrease in glass transition temperature.

[0070] In Comparative Example 7, phthalic anhydride was used as a curing agent. The phthalic anhydride reacted with the epoxy group to form a linear ester bond structure instead of a three-dimensional cross-linked network, which led to a decrease in the glass transition temperature.

[0071] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-temperature resistant epoxy resin encapsulation material, characterized in that, The product comprises the following components in parts by weight: 7-10 parts epoxy resin, 3-6 parts triglycidyl-p-aminophenol, 3-8 parts curing agent, 1-2 parts curing accelerator, 80-90 parts filler, and 1-3 parts coupling agent.

2. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, Epoxy resins include 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymers in a mass ratio of (1.3-1.5):(0.9-1.1):(0.2-0.4), 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester, and bis((3,4-epoxycyclohexyl)methyl)adipate.

3. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The type of the 2-(3,4-epoxycyclohexyl)-5,5-spiro(3,4-epoxycyclohexyl)-1,3-dioxane homopolymer is TTA-34.

4. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The 3,4-epoxycyclohexylcarboxylic acid-3',4'-epoxycyclohexylmethyl ester has an epoxy equivalent of 125-135 g / mol and a viscosity of 220-300 mPa·s at 25°C.

5. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The bis((3,4-epoxycyclohexyl)methyl)adipate has an epoxy equivalent of 190-210 g / mol and a viscosity of 500-650 mPa·s at 25 °C.

6. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The curing agent is selected from at least one of m-phenylenediamine, diaminodiphenylmethane, benzophenone tetracarboxylic anhydride, and methylhexahydrophthalic anhydride.

7. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The curing accelerator is selected from at least one of tris(dimethylaminomethyl)phenol and 2,2-(dimethylaminomethyl)phenol.

8. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The coupling agent is selected from at least one of the silane coupling agents KH550, KH560, and KH580.

9. The high-temperature resistant epoxy resin encapsulation material according to claim 1, characterized in that, The filler is fused silica powder.

10. A method for preparing a high-temperature resistant epoxy resin encapsulation material according to any one of claims 1-9, characterized in that, The process includes the following steps: mixing aliphatic epoxy resin and triglycidyl-p-aminophenol, stirring until homogeneous, adding curing agent and curing accelerator to fully dissolve them; finally adding filler and coupling agent and stirring until homogeneous; vacuuming, adding to a screw extruder for mixing and extrusion to obtain a high-temperature resistant epoxy resin encapsulation material.

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