High-temperature-resistant organosilicone gel for IGBT packaging and preparation method of high-temperature-resistant organosilicone gel

Abstract

The invention relates to the technical field of organosilicone gel, in particular to high-temperature-resistant organosilicone gel for IGBT packaging and a preparation method of the high-temperature-resistant organosilicone gel. The high-temperature-resistant organosilicone gel for IGBT packaging is prepared from a component A and a component B in a mass ratio of 1: (0.65-1), the component A is composed of vinyl-terminated silicone oil, monovinyl-terminated silicone oil and a platinum catalyst; the component B is composed of vinyl-terminated silicone oil, double-terminated hydrogen-based silicone oil, end-side hydrogen-based silicone oil, an inhibitor and a surface-functionalized nano inorganic filler; the molar ratio of Si-H to Si-Vi in the organic silicon gel is (0.4-0.8): 1. The high-temperature-resistant organic silicon gel is used as an IGBT packaging material, can resist high temperature of 200 DEG C or above for a long time without thermal oxidation, embrittling and cracking, has excellent high-temperature resistance and good electrical strength, has a good and lasting insulation protection effect on an IGBT, and prolongs the service life of an IGBT device.

Description

Technical Field

[0001] The present application relates to the technical field of organic silicone gel, and in particular to a high temperature resistant organic silicone gel for IGBT packaging and a preparation method thereof. Background Art

[0002] With the rapid development of electronic technology, the requirements for power semiconductors are getting higher and higher. Power semiconductors are the core electronic components for power control and conversion. As the "heart" of power drive, power semiconductors convert "rough electricity" into "fine electricity" for use. They are widely used in new energy vehicles, wind power converters, photovoltaic inverters, high-speed rail traction, high-voltage direct current transmission and other high-tech fields.

[0003] IGBT, also known as high-voltage and high-power insulated gate bipolar transistor, is a discrete device of the third generation of power semiconductors after bipolar transistors and metal-oxide-semiconductor field-effect transistors. It has the characteristics of easy driving, large peak current capacity, self-shutdown, and high switching frequency. It is one of the hot research objects in today's electronic market.

[0004] As IGBT devices develop towards high voltage and high power density, their insulating packaging materials are required to have better electrical, thermal and mechanical properties. However, the heat dissipation performance of conventional epoxy molding compounds is limited by the molecular structure of epoxy resin, and harmful substances are also generated during the synthesis process, which can no longer meet the packaging requirements of IGBT. Silicone gel is a special silicone rubber with "solid-liquid coexistence". It has the advantages of high elasticity, low stress, extremely small Young's modulus, and excellent heat resistance. It is currently the most popular IGBT packaging material. It can provide better vibration reduction protection for IGBT devices. At the same time, it can work stably under large temperature fluctuations and strong vibration conditions, effectively reducing the structural damage of electrical stress and thermal stress to the bonding wires in IGBT devices, thereby extending the service life of IGBT devices.

[0005] At present, the highest operating junction temperature of IGBT semiconductor chips is usually 150℃, and the heat resistance temperature requirement for silicone gel used for IGBT packaging is 175℃, that is, the chemical structure of silicone gel used for IGBT packaging is relatively low at 175℃ for a long time, and it is not easy to be oxidized by heat and cross-linked and hardened, which will affect the protection of IGBT packaging. As IGBT devices further develop in the direction of high voltage and high power density, the heat resistance temperature of traditional silicone gel used for IGBT packaging will become hard and brittle after being affected by long-term heat at around 200℃, completely losing elasticity and cracking, which can no longer meet the packaging requirements of the new generation of IGBT devices. A high-temperature resistant silicone gel for IGBT packaging is urgently needed. Summary of the invention

[0006] In order to meet the packaging requirements of a new generation of IGBT devices, the present application provides a high temperature resistant silicone gel for IGBT packaging and a preparation method thereof.

[0007] In the first aspect, the present application provides a high temperature resistant silicone gel for IGBT packaging, which is achieved through the following technical solutions: A high-temperature resistant organic silicone gel for IGBT encapsulation is prepared from component A and component B in a mass ratio of 1:(0.65-1); the component A is prepared from the following raw materials in mass parts: 76-83.99 parts of vinyl-terminated silicone oil, 16-24 parts of monovinyl-terminated silicone oil, and 0.01-2.0 parts of platinum catalyst; the component B is prepared from the following raw materials in mass parts: 68-82 parts of vinyl-terminated silicone oil, 16-28 parts of double-terminated hydrogen-based silicone oil acting as a chain extender, 1.2-2.8 parts of end-side hydrogen-based silicone oil acting as a cross-linking agent, 0.01-0.20 parts of an inhibitor, and 0.05-0.5 parts of a surface functionalized nano inorganic filler; the molar ratio of Si-H to Si-Vi in the high-temperature resistant organic silicone gel for IGBT encapsulation is (0.4-0.8):1.

[0008] The high temperature resistant organic silicone gel of the present invention can be used as an IGBT packaging material and can withstand high temperatures above 200°C for a long time without thermal oxidation, brittleness or cracking, has excellent high temperature resistance, and also has good electrical strength, plays a good and lasting insulating and protective role for the IGBT, and prolongs the service life of the IGBT device.

[0009] Preferably, the molar ratio of Si-H to Si-Vi in the high-temperature resistant silicone gel for IGBT encapsulation is (0.43-0.52):1. At the same time, the amount of end-side hydrogen-based silicone oil in component B that acts as a cross-linking agent also needs to be limited. If the cross-linking density is too high, the hardness of the finished high-temperature resistant silicone gel for IGBT encapsulation will be too large, and the electrical stress and thermal stress cannot be effectively eliminated, resulting in poor vibration damping protection of the prepared high-temperature resistant silicone gel for IGBT encapsulation; and too low a cross-linking density will affect the oil permeability of the high-temperature resistant silicone gel. As the material is used for a long time at high temperature, liquid seepage will occur. The seepage of small silicone molecules or inert small molecules will not only contaminate electrical components such as electrodes and reduce the sealing and bonding to electrical components, but also reduce its own flexibility and mechanical properties.

[0010] The functional groups contained in the surface functionalized nano-inorganic filler can make it have good compatibility with the silicone resin system, that is, the surface functionalized nano-inorganic filler can be evenly dispersed in the silicone resin system to avoid the agglomeration of the surface functionalized nano-inorganic filler at the nano level and affect the overall flexibility, mechanical strength and heat stability. In addition, the functional groups contained in the surface functionalized nano-inorganic filler will also produce a bonding reaction with the double-terminal hydrogen-based silicone oil and the end-side hydrogen-based silicone oil, that is, the surface functionalized nano-inorganic filler can improve the overall cross-linking density, so it is necessary to strictly control its addition amount. If the addition amount of the surface functionalized nano-inorganic filler is too low, the high temperature resistance and oil permeation resistance will not be significantly improved, while if the addition amount of the surface functionalized nano-inorganic filler is too high, although the overall heat resistance and oil permeation resistance are improved, the overall hardness is too large and the flexibility is significantly reduced, which is not conducive to the shock absorption protection of the IGBT device.

[0011] Therefore, optimizing the molar ratio of Si-H and Si-Vi and the amount of end-side hydrogen-based silicone oil and surface functionalized nano-inorganic filler in the formula can effectively improve the heat resistance, flexibility, mechanical strength and oil resistance of the high-temperature resistant silicone gel for IGBT encapsulation. The prepared high-temperature resistant silicone gel can effectively protect the IGBT and extend the service life of the IGBT.

[0012] Preferably, the surface functionalized nano inorganic filler is a nano inorganic filler with surface grafted vinyl silane, and the nano inorganic filler is at least one of nano spherical alumina, halloysite nanotubes, and hexagonal nitride nanosheets, and the sheet diameter of the hexagonal nitride nanosheet is 50-200nm; the average particle size of the nano spherical alumina is 20-100nm.

[0013] Nano-spherical alumina can toughen and reinforce high-temperature resistant silicone gel and improve its heat dissipation performance. The spherical nano-filler structure makes the high-temperature resistant silicone gel produced by it have good fluidity, which is convenient for IGBT device glue filling processing. In addition, nano-spherical alumina will produce friction resistance to the migration of polysiloxane molecular chains, which is beneficial to improve the overall anti-oil penetration performance.

[0014] Halloysite nanotubes can toughen and reinforce high-temperature resistant silicone gel and improve its heat dissipation performance. The nanotube structure of halloysite can improve the heat resistance of high-temperature resistant silicone gel more significantly. In addition, it can physically and chemically adsorb the polysiloxane molecular chains in both directions, increase the difficulty of migration of the polysiloxane molecular chains, and thus help improve the overall anti-oil permeation performance.

[0015] It should be noted that the addition of halloysite nanotubes significantly improves the hardness of the high-temperature resistant silicone gel. The addition amount of surface-functionalized halloysite nanotubes is relatively lower than that of surface-functionalized nano-spherical alumina and surface-functionalized hexagonal nitride nanosheets to ensure flexibility.

[0016] Hexagonal nitride nanosheets can better toughen and reinforce high temperature resistant silicone gel and improve the overall heat dissipation performance more significantly. The disadvantage is that the price of hexagonal nitride nanosheets is relatively expensive. Hexagonal nitride nanosheets will produce friction resistance to the migration of polysiloxane molecular chains, which is beneficial to improve the overall oil resistance.

[0017] Preferably, the surface functionalized nano inorganic filler is a hexagonal nitride nanosheet with vinyl silane grafted on the surface, and the preparation method of the hexagonal nitride nanosheet with vinyl silane grafted on the surface is as follows: S1. firstly subjecting the hexagonal nitride nanosheets to thermal activation treatment; S2. ball milling the thermally activated hexagonal nitride nanosheets; S3. The ball-milled hexagonal nitride nanosheets are subjected to low-temperature plasma modification to obtain hydroxylated hexagonal nitride nanosheets; S4. 3-5 parts of hydroxylated modified hexagonal nitride nanosheets and 0.01-0.02 parts of an inhibitor were added to 100-120 parts of a 4-8wt% aqueous solution of vinyl silane, mixed well and subjected to ultrasonic dispersion treatment for 15-30min to obtain a dispersion; S5. The obtained dispersion is filtered, and the obtained solid is vacuum dried and then ball-milled to obtain hexagonal nitride nanosheets with surface grafted vinyl silane.

[0018] The preparation method of hexagonal nitride nanosheets with surface grafted vinyl silane is relatively simple, which reduces the industrial use cost of hexagonal nitride nanosheets with surface grafted vinyl silane, and thus facilitates the promotion and application of high-temperature resistant silicone gel for IGBT packaging.

[0019] Preferably, the A component is made of the following raw materials in parts by mass: 80 parts of vinyl-terminated silicone oil, 19 parts of monovinyl-terminated silicone oil, and 1 part of platinum catalyst; the B component is made of the following raw materials in parts by mass: 77-80 parts of vinyl-terminated silicone oil, 17-20 parts of double-terminated hydrogen-based silicone oil acting as a chain extender, 1.70-1.85 parts of end-side hydrogen-based silicone oil acting as a cross-linking agent, 0.10-0.20 parts of inhibitors, and 0.20-0.30 parts of surface functionalized nano-inorganic fillers.

[0020] By optimizing the content of component A and component B in the formula, the hardness, flexibility and heat resistance of the high-temperature resistant silicone gel for IGBT packaging can be effectively improved, and it can withstand higher temperatures for a long time without becoming brittle and cracking due to thermal oxidation.

[0021] Preferably, the vinyl-terminated silicone oil in the component A contains 40-60 wt % of vinyl-sealed polysiloxane containing benzene rings in its molecular chain.

[0022] By introducing phenyl groups into the polysiloxane molecular chain, the overall high temperature resistance performance of the high temperature resistant silicone gel for IGBT encapsulation can be improved, that is, it can withstand higher temperatures for a long time without thermal oxidation, brittleness and cracking. It should be noted that the amount of vinyl-sealed polysiloxane containing benzene rings in the molecular chain should be added. If too much phenyl groups are introduced into the polysiloxane molecular chain, the rigidity of the high temperature resistant silicone gel for IGBT encapsulation will increase, the flexibility will decrease, and the hardness will increase, making it more brittle, which is not conducive to the vibration reduction protection of the IGBT.

[0023] Preferably, the dual-terminal hydrogen-based silicone oil in the B component that acts as a chain extender contains 40-60 wt % of a dual-terminal hydrogen-based terminated polysiloxane having a benzene ring in its molecular chain.

[0024] By introducing phenyl groups into the polysiloxane molecular chain, the overall high temperature resistance performance of the high temperature resistant silicone gel for IGBT encapsulation can be improved, that is, it can withstand higher temperatures for a long time without thermal oxidation, brittleness and cracking. It should be noted that the amount of vinyl-sealed polysiloxane containing benzene rings in the molecular chain should be added. If too much phenyl groups are introduced into the polysiloxane molecular chain, the rigidity of the high temperature resistant silicone gel for IGBT encapsulation will increase, the flexibility will decrease, and the hardness will increase, making it more brittle, which is not conducive to the vibration reduction protection of the IGBT.

[0025] Preferably, the vinyl-terminated silicone oil in component A contains 25-30wt% of vinyl-capped polysiloxane having a benzene ring in its molecular chain, and the dual-terminated hydrogen-based silicone oil in component B that acts as a chain extender contains 20-40wt% of dual-terminated hydrogen-capped polysiloxane having a benzene ring in its molecular chain.

[0026] Whether only introducing a benzene ring structure into the terminal vinyl silicone oil molecular chain of component A or only introducing a benzene ring structure into the double-terminal hydrogen-based silicone oil molecular chain that acts as a chain extender of component B, although both methods can improve the overall high temperature resistance, the distribution uniformity of the benzene rings in the three-dimensional cross-linked network structure is general under the above two methods. By simultaneously introducing a benzene ring structure into the terminal vinyl silicone oil molecular chain of component A and into the double-terminal hydrogen-based silicone oil molecular chain that acts as a chain extender of component B and strictly controlling the benzene ring content, the high temperature resistant silicone gel for IGBT encapsulation prepared therefrom can be endowed with better high temperature resistance.

[0027] Preferably, the inhibitor is at least one of 1-ethynylcyclohexanol, (S)-5-phenyl-1-pentyn-3-ol, 3-octyl-1-butyn-3-ol, and 3-methyl-1-butyn-3-ol.

[0028] In the second aspect, the present application provides a method for preparing a high temperature resistant silicone gel for IGBT packaging, which is achieved by the following technical solutions: A method for preparing a high temperature resistant silicone gel for IGBT packaging comprises the following steps: Preparation of component A: Mix accurately measured vinyl-terminated silicone oil and monovinyl-terminated silicone oil evenly, add accurately measured platinum catalyst, stir evenly, and perform vacuum degassing to obtain component A; Preparation of component B: first prepare a surface functionalized nano inorganic filler, then mix the vinyl-terminated silicone oil, the double-terminated hydrogen-based silicone oil, the side-terminated hydrogen-based silicone oil, the inhibitor, and the surface functionalized nano inorganic filler uniformly, and then perform vacuum degassing to obtain component B; When in use, component A and component B are evenly mixed in a mass ratio of 1:(0.65-1) to obtain a finished high temperature resistant silicone gel.

[0029] The preparation method of the present invention is relatively simple, has low operation difficulty, and is convenient for achieving the purpose of industrialized production.

[0030] The application of high-temperature resistant silicone gel for IGBT packaging in high-power IGBT packaging is to first dry the IGBT module, and the drying parameters are as follows: pre-bake at 80-95℃ for 20-24h to remove residual moisture; when in use, mix component A and component B at a mass ratio of 1:(0.65-1) to obtain a finished high-temperature resistant silicone gel; pour the finished high-temperature resistant silicone gel into the IGBT module that has been dried, and vacuum degas for 5-10min at a pressure of 0.08-0.1MPa. After the filling is completed, it is cured at a temperature of 80-120℃ for 1-5h, and demolding can complete the silicone gel packaging of the IGBT module.

[0031] In summary, this application has the following advantages: 1. The high temperature resistant silicone gel of the present invention can be used as an IGBT packaging material and can withstand high temperatures above 200°C for a long time without thermal oxidation, brittleness or cracking. It has excellent high temperature resistance and good electrical strength, and plays a good and lasting insulation protection role for the IGBT, thereby extending the service life of the IGBT device.

[0032] 2. The preparation method of the present invention is relatively simple, has low operating difficulty, and is easy to realize industrial production, thereby reducing the production cost of high-temperature resistant silicone gel for IGBT packaging and facilitating rapid marketing. DETAILED DESCRIPTION

[0033] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples and comparative examples.

[0034] Preparation Example 1: The surface functionalized nano inorganic filler is a hexagonal nitride nanosheet with vinyl silane grafted on the surface, and the preparation method thereof is as follows: S1. First, heat-activate the hexagonal nitride nanosheets (hexagonal nitride nanosheets with the product number XT-BN-01 from Shanghai Xiangtian Nanomaterial Co., Ltd., with a specification of 120 nm) at 200°C for 2 h and set aside; S2. The hexagonal nitride nanosheets treated with heat activation were added to a planetary ball mill and the speed was adjusted to 80 rpm for dry ball milling for 30 min; S3. The ball-milled hexagonal nitride nanosheets were subjected to low-temperature plasma modification. Specifically, the dry-milled hexagonal nitride nanosheets in S2 were placed in a plasma surface treatment instrument, and ozone was introduced at 0-4°C for low-temperature plasma treatment for 8 minutes. The plasma generator frequency was 40KHz, and the gas flow rate under the float needle valve flow controller was 1.5L / min to obtain hydroxylated modified hexagonal nitride nanosheets; S4. 5 g of hydroxylated modified hexagonal nitride nanosheets and 0.05 g of inhibitor - benzoquinone were added to 100 g of a 4 wt % aqueous solution of dimethoxymethylvinylsilane (CAS No. 16753-62-1), mixed well, and then subjected to ultrasonic dispersion treatment for 30 min at an ultrasonic frequency of 40 kHz / power of 600 W to obtain a dispersion; S5. The obtained dispersion is filtered, and the obtained solid is placed in a vacuum drying oven, and dried at 105°C for 4 hours at an internal pressure of 10Pa to obtain a solid material. The obtained solid material is placed in a planetary ball mill for fine ball milling treatment, and the ball milling is performed at a speed of 60rpm for 30min to obtain hexagonal nitride nanosheets with surface grafted vinyl silane.

[0035] The difference between Preparation Example 2 and Preparation Example 1 is: S1. First, the hexagonal nitride nanosheets (hexagonal nitride nanosheets with the product number XT-BN-04 of Shanghai Xiangtian Nanomaterial Co., Ltd., with a specification of 800 nm) are placed at 200° C. for thermal activation treatment for 2 h and set aside.

[0036] The difference between Preparation Example 3 and Preparation Example 1 is that the surface-functionalized nano-inorganic filler is nano-spherical alumina with vinyl silane grafted on the surface.

[0037] The difference between the preparation method of nano-spherical alumina with surface grafted vinyl silane and the preparation method of hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 1 is that the hexagonal nitride nanosheets are replaced by nano-spherical alumina (α-spherical alumina with product number XT-AL203-03 of Shanghai Xiangtian Nanomaterials Co., Ltd., with a specification of 80nm), and the other steps are the same.

[0038] The difference between Preparation Example 4 and Preparation Example 1 is that the surface-functionalized nano-inorganic filler is nano-spherical alumina with vinyl silane grafted on the surface.

[0039] The difference between the preparation method of nano-spherical alumina with surface grafted vinyl silane and the preparation method of hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 1 is that the hexagonal nitride nanosheets are replaced by nano-spherical alumina (α-spherical alumina with product number XT-AL203-07 of Shanghai Xiangtian Nanomaterials Co., Ltd., with a specification of 1 micron), and the other steps are the same.

[0040] The difference between Preparation Example 5 and Preparation Example 1 is that the surface-functionalized nano inorganic filler is a halloysite nanotube with vinyl silane grafted on the surface.

[0041] The difference between the preparation method of halloysite nanotubes with surface grafted vinyl silane and the preparation method of hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 1 is that the hexagonal nitride nanosheets are replaced by halloysite nanotubes with a diameter of 50-300nm, a length of 1-10μm, and a purity of greater than 95at%. Order from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd. Example

[0042] A high temperature resistant organic silicon gel for IGBT packaging is prepared from component A and component B in a mass ratio of 1:(0.65-1).

[0043] Component A is prepared from the following raw materials in parts by mass: 76-83.99 parts of vinyl-terminated silicone oil, 16-24 parts of monovinyl-terminated silicone oil, and 0.01-2.0 parts of platinum catalyst.

[0044] Preferably, component A is made of the following raw materials in parts by mass: 80 parts of vinyl-terminated silicone oil, 19 parts of monovinyl-terminated silicone oil, and 1 part of platinum catalyst.

[0045] Component B is made of the following raw materials in parts by mass: 68-82 parts of vinyl-terminated silicone oil, 16-28 parts of double-terminated hydrogen-based silicone oil acting as a chain extender, 1.2-2.8 parts of side-terminated hydrogen-based silicone oil acting as a crosslinking agent, 0.01-0.20 parts of an inhibitor, and 0.05-0.5 parts of a surface functionalized nano inorganic filler.

[0046] The inhibitor is at least one of 1-ethynylcyclohexanol, (S)-5-phenyl-1-pentyn-3-ol, 3-octyl-1-butyn-3-ol, and 3-methyl-1-butyn-3-ol, and is preferably (S)-5-phenyl-1-pentyn-3-ol.

[0047] Preferably, component B is made of the following raw materials in parts by mass: 77-80 parts of vinyl-terminated silicone oil, 17-20 parts of double-terminated hydrogen-based silicone oil acting as a chain extender, 1.70-1.85 parts of side-terminated hydrogen-based silicone oil acting as a cross-linking agent, 0.10-0.20 parts of an inhibitor, and 0.20-0.30 parts of a surface functionalized nano-inorganic filler.

[0048] The molar ratio of Si-H and Si-Vi in the high temperature resistant silicone gel for IGBT packaging is (0.4-0.8):1. Preferably, the molar ratio of Si—H to Si—Vi is (0.43-0.52):1.

[0049] In actual industrial production, the preferred formula is a Si-H to Si-Vi molar ratio of (0.48-0.52):1.

[0050] The surface functionalized nano inorganic filler is a nano inorganic filler with vinyl silane grafted on the surface. The nano inorganic filler in the nano inorganic filler with vinyl silane grafted on the surface is at least one of nano spherical alumina, halloysite nanotubes, and hexagonal nitride nanosheets.

[0051] When the nano inorganic filler is hexagonal nitride nanosheets, the sheet diameter is preferably 50-200 nm.

[0052] When the nano inorganic filler is nano spherical alumina, the average particle size thereof is preferably 20-100 nm.

[0053] Preferably, the surface functionalized nano inorganic filler is a hexagonal nitrided nanosheet with vinyl silane grafted on the surface. The preparation method of the hexagonal nitrided nanosheet with vinyl silane grafted on the surface can be found in the preparation example.

[0054] Under the premise of ensuring the overall flexibility of the high temperature resistant silicone gel, in order to improve the overall heat resistance of the high temperature resistant silicone gel, the mid-terminal vinyl silicone oil in component A contains 40-60wt% of vinyl-sealed polysiloxane with benzene rings in the molecular chain, and the remainder is vinyl-sealed polysiloxane without benzene rings in the molecular chain.

[0055] Alternatively, under the premise of ensuring the overall flexibility of the high temperature resistant silicone gel, in order to improve the overall heat resistance of the high temperature resistant silicone gel, the double-terminal hydrogen-based silicone oil acting as a chain extender in component B contains 40-60wt% of double-terminal hydrogen-based terminated polysiloxane whose molecular chain contains benzene rings, and the remainder is double-terminal hydrogen-based terminated polysiloxane whose molecular chain does not contain benzene rings.

[0056] Preferably, under the premise of ensuring the overall flexibility of the high-temperature resistant silicone gel, in order to improve the overall heat resistance of the high-temperature resistant silicone gel, the end-vinyl silicone oil in component A contains 25-30wt% of vinyl-capped polysiloxane containing benzene rings in the molecular chain, and the double-terminal hydrogen-based silicone oil acting as a chain extender in component B contains 20-40wt% of double-terminal hydrogen-capped polysiloxane containing benzene rings in the molecular chain.

[0057] A method for preparing a high temperature resistant silicone gel for IGBT packaging comprises the following steps: Preparation of component A: Mix accurately measured vinyl-terminated silicone oil and monovinyl-terminated silicone oil evenly, add accurately measured platinum catalyst, stir evenly, and perform vacuum degassing to obtain component A; Preparation of component B: first prepare a surface functionalized nano inorganic filler, then mix the vinyl-terminated silicone oil, the double-terminated hydrogen-based silicone oil, the side-terminated hydrogen-based silicone oil, the inhibitor, and the surface functionalized nano inorganic filler uniformly, and then perform vacuum degassing to obtain component B; When in use, component A and component B are evenly mixed in a mass ratio of 1:(0.65-1) to obtain a finished high temperature resistant silicone gel.

[0058] The application of high-temperature resistant silicone gel for IGBT packaging in high-power IGBT packaging is to first dry the IGBT module, and the drying parameters are as follows: pre-bake at 80-95℃ for 20-24h to remove residual moisture; when in use, mix component A and component B at a mass ratio of 1:(0.65-1) to obtain a finished high-temperature resistant silicone gel; pour the finished high-temperature resistant silicone gel into the IGBT module that has been dried, and vacuum degas for 5-10min at a pressure of 0.08-0.1MPa. After the filling is completed, it is cured at a temperature of 80-120℃ for 1-5h, and demolding can complete the silicone gel packaging of the IGBT module.

[0059] Example 1: The high temperature resistant organic silicone gel for IGBT encapsulation is made of component A and component B in a mass ratio of 1:1. Component A is made of the following raw materials in mass parts: 80 parts of vinyl-terminated silicone oil (vinyl-terminated polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 19 parts of monovinyl-terminated silicone oil (grade MCR-V21, product of Gelest Company), and 1 part of platinum catalyst (Karstedt, 5000ppm, product of Dongguan Dongsheng Synthetic Materials Co., Ltd.).

[0060] Component B is made of the following raw materials in parts by mass: 78 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.05 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0061] A method for preparing a high temperature resistant silicone gel for IGBT packaging comprises the following steps: Preparation of component A: 80 parts of accurately measured vinyl-terminated silicone oil (vinyl-terminated polydimethylsiloxane, viscosity 100 mPa*s, vinyl content 1.0 wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) and 19 parts of monovinyl-terminated silicone oil (grade MCR-V21, product of Gelest Company) were mixed evenly, and then 1 part of accurately measured platinum catalyst (Karstedt, 5000 ppm, product of Dongguan Dongsheng Synthetic Materials Co., Ltd.) was added, and mechanical stirring was carried out at 80 rpm for 10 minutes, and then vacuum degassing treatment was carried out for 30 minutes to obtain component A; Preparation of component B: First, prepare a surface functionalized nano-inorganic filler, refer to the preparation of hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 1, and then add 78 parts of vinyl-terminated silicone oil (vinyl-terminated polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminated hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminated hydrogen-capped polydimethylsiloxane, Anhui Aiyota Silicone Oil Co., Ltd.) as a chain extender. 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a crosslinking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), 0.05 parts of the hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 1 were mechanically stirred at 80 rpm for 10 minutes and then vacuum degassed for 30 minutes to obtain component B; When in use, component A and component B are uniformly mixed in a mass ratio of 1:1 to obtain a finished high temperature resistant organic silicone gel, and the Si-H / Si-Vi molar ratio of the finished high temperature resistant organic silicone gel is 0.495 / 1.00.

[0062] The difference between Example 2 and Example 1 is that component B is made of the following raw materials in parts by mass: 77.95 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.1 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0063] The difference between Example 3 and Example 1 is that component B is made of the following raw materials in parts by mass: 77.85 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.2 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0064] The difference between Example 4 and Example 1 is that component B is made of the following raw materials in parts by mass: 77.75 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0065] The difference between Example 5 and Example 1 is that component B is made of the following raw materials in parts by mass: 77.65 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.4 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0066] The difference between Example 6 and Example 1 is that component B is made of the following raw materials in parts by mass: 77.55 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.5 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0067] The difference between Example 7 and Example 1 is that component B is made of the following raw materials in parts by mass: 79.9 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 18 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.7 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high temperature resistant silicone gel is 0.437 / 1.00.

[0068] The difference between Example 8 and Example 1 is that component B is made of the following raw materials in parts by mass: 81.6 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 16.4 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.6 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high temperature resistant silicone gel is 0.404 / 1.00.

[0069] The difference between Example 9 and Example 1 is that component B is made of the following raw materials in parts by mass: 76.6 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 21 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 2 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high temperature resistant silicone gel is 0.519 / 1.00.

[0070] The difference between Example 10 and Example 1 is that component B is made of the following raw materials in parts by mass: 72 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 25 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 2.5 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high temperature resistant silicone gel is 0.649 / 1.00.

[0071] The difference between Example 11 and Example 8 is that component A is made of the following raw materials in parts by mass: 40 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Iota Silicone Oil Co., Ltd.), 40 parts of phenyl vinyl silicone oil (IOTA252, customized by Anhui Iota Silicone Oil Co., Ltd., molecular weight 6000, vinyl content 0.8wt%, phenyl content of 55wt%), 19 parts of monovinyl terminated silicone oil (grade MCR-V21, product of Gelest Company), and 1 part of platinum catalyst (Karstedt, 5000ppm, product of Dongguan Dongsheng Synthetic Materials Co., Ltd.).

[0072] The difference between Example 12 and Example 8 is that component B is made of the following raw materials in parts by weight: 82 parts of vinyl-terminated silicone oil (vinyl-terminated polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Iyota Silicone Oil Co., Ltd.), 9.6 parts of double-terminated hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminated hydrogen-terminated polydimethylsiloxane, customized by Anhui Iyota Silicone Oil Co., Ltd.) acting as a chain extender, and 6.4 parts of hydrogen-terminated phenyl silicone oil IOTA231 (molecular weight 1500, active hydrogen content 0.13wt%, double-terminated hydrogen-terminated polydimethylsiloxane, customized by Anhui Iyota Silicone Oil Co., Ltd.) 1000 molecular weight, active hydrogen content 0.2wt%, viscosity 100mPa*s, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 1.6 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high-temperature resistant silicone gel is 0.452 / 1.00.

[0073] The difference between Example 13 and Example 12 is that component B is made of the following raw materials in parts by mass: 82 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Iyota Silicone Oil Co., Ltd.), 9.6 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Iyota Silicone Oil Co., Ltd.) acting as a chain extender, 6.4 parts of hydrogen-terminated phenyl silicone oil IOTA231 (molecular weight 1000, active hydrogen content 0.2wt%, viscosity 100mPa*s, customized by Anhui Iyota Silicone Oil Co., Ltd. 0.8 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.8 parts of methyl-terminated end-side hydrogen-containing silicone oil 25H-0.3 (active hydrogen content 0.32wt%, fluorine content 12.3wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high-temperature resistant silicone gel is 0.479 / 1.00.

[0074] The difference between Example 14 and Example 13 is that component A is made of the following raw materials in parts by mass: 40 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Iota Silicone Oil Co., Ltd.), 40 parts of phenyl vinyl silicone oil (IOTA252, customized by Anhui Iota Silicone Oil Co., Ltd., molecular weight 6000, vinyl content 0.8wt%, phenyl content of 55wt%), 19 parts of monovinyl terminated silicone oil (grade MCR-V21, product of Gelest Company), and 1 part of platinum catalyst (Karstedt, 5000ppm, product of Dongguan Dongsheng Synthetic Materials Co., Ltd.).

[0075] The difference between Example 15 and Example 14 is that the hexagonal nitride nanosheets with vinyl silane grafted on the surface in Preparation Example 1 are replaced by nano-spherical alumina with vinyl silane grafted on the surface in Preparation Example 3.

[0076] The difference between Example 16 and Example 14 is that the hexagonal nitride nanosheets with vinyl silane grafted on the surface in Preparation Example 1 are replaced by the halloysite nanotubes with vinyl silane grafted on the surface in Preparation Example 5.

[0077] The difference between Comparative Example 1 and Example 1 is that component B is made of the following raw materials in parts by mass: 80.05 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, and 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1).

[0078] The difference between Comparative Example 2 and Example 1 is that component B is made of the following raw materials in parts by mass: 80.03 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of (S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.02 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0079] The difference between Comparative Example 3 and Example 1 is that component B is made of the following raw materials in parts by mass: 77.45 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 20 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.85 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of (S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.60 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1.

[0080] The difference between Comparative Example 4 and Example 1 is that component B is made of the following raw materials in parts by mass: 66.4 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 30 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 3.2 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a cross-linking agent, 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high temperature resistant silicone gel is 0.814 / 1.00.

[0081] The difference between Comparative Example 5 and Example 1 is that component B is made of the following raw materials in parts by mass: 86.2 parts of terminal vinyl silicone oil (terminal vinyl polydimethylsiloxane, viscosity 100mPa*s, vinyl content 1.0wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 12 parts of double-terminal hydrogen-based silicone oil (ITOA-616, molecular weight 1500, active hydrogen content 0.13wt%, double-terminal hydrogen-terminated polydimethylsiloxane, customized by Anhui Aiyota Silicone Oil Co., Ltd.) acting as a chain extender, 1.4 parts of end-side hydrogen-based silicone oil (methyl-terminated end-side hydrogen-containing silicone oil ITOA-203, molecular weight 650, active hydrogen content 0.46wt%, customized by Anhui Aiyota Silicone Oil Co., Ltd.), 0.1 parts of inhibitor-(S)-5-phenyl-1-pentyn-3-ol (CAS No.: 183904-28-1), and 0.3 parts of hexagonal nitrided nanosheets with surface grafted vinyl silane in Preparation Example 1. The Si-H / Si-Vi molar ratio of the finished high temperature resistant silicone gel is 0.305 / 1.00.

[0082] The difference between Comparative Example 6 and Example 14 is that the hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 1 are replaced by the hexagonal nitride nanosheets with surface grafted vinyl silane in Preparation Example 2.

[0083] The difference between Comparative Example 7 and Example 14 is that the hexagonal nitride nanosheets with vinyl silane grafted on the surface in Preparation Example 1 are replaced by nano-spherical alumina with vinyl silane grafted on the surface in Preparation Example 4.

[0084] Test sample: First dry the mold with the following drying parameters: pre-bake at 95°C for 24 hours to remove residual moisture; when in use, mix component A and component B in a mass ratio of 1:1 to obtain the finished high-temperature resistant silicone gel; pour the finished high-temperature resistant silicone gel into the mold that has been dried, and vacuum degas at a pressure of 0.08-0.1MPa for 10 minutes, then cure at 120°C for 1 hour, and demold.

[0085] 1. Cone penetration tester: SN-ZRD2000 is used for the measurement.

[0086] 2. Volume resistivity test method: According to IEC62631-3-1-2016, the test method is the three-electrode method, the lower flat electrode diameter d1 = 58mm, the upper flat electrode diameter d2 = 50mm, the inner and outer diameters of the annular auxiliary electrode d3 = 54mm, d4 = 58mm, the test voltage is 1000VDC, and the test temperature is 150℃.

[0087] 3. Electric strength test method: Measured in accordance with IEC60243-1-2013 test method.

[0088] 4. Test method for cone penetration change rate: Under 250°C, the duration T of cone penetration change rate ≤15% reflects the heat resistance of silicone gel for IGBT encapsulation, and the acceptance standard is T≥30h.

[0089] 5. Oil penetration performance test: Place the same mass of organic silicone gel for IGBT encapsulation on filter paper, place it in a vacuum oven at a temperature of 100℃ and a vacuum degree of -0.1MPa, and observe the oil penetration performance of the organic silicone gel sample for IGBT encapsulation from 0 to 120 hours. The oil penetration performance is expressed by the oil penetration rate r, r=Dm / D0, D0 is the initial diameter of the sample; Dm is the diameter of the sample including the oil mark after oil penetration.

[0090] Table 1: Test parameters of silicone gel for IGBT encapsulation in Examples 1-16 and Comparative Examples 1-7

[0091] Note: The above-mentioned silicone gel for IGBT encapsulation has a uniform colorless and transparent liquid appearance.

[0092] It can be seen from Examples 1-6 and Comparative Examples 1-3 and Table 1 that based on the formula provided by the present invention, the amount of surface functionalized nano inorganic filler added is preferably controlled to be 0.05-0.50 parts, which can improve the overall high temperature resistance and insulation safety performance, and maintain relatively good flexibility.

[0093] Combining Examples 7-10 and Comparative Examples 4-5 and Table 1, it can be seen that the molar ratio of Si-H and Si-Vi in the high-temperature resistant silicone gel for IGBT encapsulation is preferably controlled at (0.40-0.8):1. When the amount of surface functionalized nano-inorganic filler added is controlled to 0.3 parts, the molar ratio of Si-H and Si-Vi is preferably (0.43-0.52):1, and it can withstand high temperatures above 200°C for a long time without thermal oxidation, brittle cracking, and excellent high temperature resistance. When the molar ratio of Si-H and Si-Vi is greater than 0.8:1, the hardness of the silicone gel is too large and cannot meet the IGBT encapsulation requirements. In industrial design, the adjustment range of the molar ratio of Si-H and Si-Vi is controlled between 0.4-0.65.

[0094] It can be seen from Example 8 and Examples 11-14 and Table 1 that the introduction of an appropriate amount of benzene rings into the molecular chain can improve the overall high temperature resistance while ensuring its softness, and the product penetration is ≥270mm / 10.

[0095] It can be seen from Example 1 and Comparative Example 5 and Table 1 that the average particle size of hexagonal nano-boron nitride affects the heat resistance, electrical strength and volume resistivity of the silicone gel for IGBT encapsulation. The silicone gel for IGBT encapsulation prepared by using the hexagonal nitride nanosheets with surface grafted vinyl silane of Preparation Example 1 in this application has better comprehensive performance.

[0096] It can be seen from Example 15 and Comparative Example 6 and Table 1 that the average particle size of the spherical nano-alumina affects the heat resistance, electrical strength and volume resistivity of the silicone gel for IGBT encapsulation. The silicone gel for IGBT encapsulation prepared by using the spherical nano-alumina with surface grafted vinyl silane in Preparation Example 1 of this application has better comprehensive performance.

[0097] In summary, the high temperature resistant silicone gel in the present invention can be used as an IGBT packaging material and can withstand high temperatures above 200°C for a long time without thermal oxidation, brittleness or cracking. It has excellent high temperature resistance and good electrical strength, and can provide good and lasting insulation protection for the IGBT, thereby extending the service life of the IGBT device.

[0098] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A high temperature resistant silicone gel for IGBT encapsulation, characterized in that: The high temperature resistant organic silicone gel for IGBT encapsulation is made of component A and component B in a mass ratio of 1:(0.65-1); The A component is made of the following raw materials in parts by mass: 76-83.99 parts of vinyl-terminated silicone oil, 16-24 parts of monovinyl-terminated silicone oil, and 0.01-2.0 parts of platinum catalyst; The B component is made of the following raw materials in parts by mass: 68-82 parts of vinyl-terminated silicone oil, 16-28 parts of double-terminated hydrogen-based silicone oil acting as a chain extender, 1.6-2.8 parts of side-terminated hydrogen-based silicone oil acting as a cross-linking agent, 0.01-0.20 parts of an inhibitor, and 0.05-0.5 parts of a surface functionalized nano inorganic filler; The molar ratio of Si-H to Si-Vi in the high temperature resistant silicone gel for IGBT packaging is (0.4-0.8):

1.

2. The high temperature resistant silicone gel for IGBT encapsulation according to claim 1, characterized in that: The surface functionalized nano inorganic filler is a nano inorganic filler with surface grafted vinyl silane, and the nano inorganic filler is at least one of nano spherical alumina, halloysite nanotubes, and hexagonal nitride nano sheets, and the sheet diameter of the hexagonal nitride nano sheets is 50-200nm; the average particle size of the nano spherical alumina is 20-100nm.

3. The high temperature resistant silicone gel for IGBT encapsulation according to claim 2, characterized in that: The surface functionalized nano inorganic filler is a hexagonal nitrided nano sheet with vinyl silane grafted on the surface. The preparation method of the hexagonal nitrided nano sheet with vinyl silane grafted on the surface is as follows: S1. firstly subjecting the hexagonal nitride nanosheets to thermal activation treatment; S2. ball milling the thermally activated hexagonal nitride nanosheets; S3. The ball-milled hexagonal nitride nanosheets are subjected to low-temperature plasma modification to obtain hydroxylated hexagonal nitride nanosheets; S4. 3-5 parts of hydroxylated modified hexagonal nitride nanosheets and 0.01-0.02 parts of an inhibitor were added to 100-120 parts of a 4-8wt% aqueous solution of vinyl silane, mixed well and subjected to ultrasonic dispersion treatment for 15-30min to obtain a dispersion; S5. The obtained dispersion is filtered, and the obtained solid is vacuum dried and then ball-milled to obtain hexagonal nitride nanosheets with surface grafted vinyl silane.

4. The high temperature resistant silicone gel for IGBT encapsulation according to claim 3, characterized in that: The A component is made of the following raw materials in parts by mass: 80 parts of vinyl-terminated silicone oil, 19.5-19 parts of monovinyl-terminated silicone oil, and 1 part of platinum catalyst; the B component is made of the following raw materials in parts by mass: 77-80 parts of vinyl-terminated silicone oil, 17-20 parts of double-terminated hydrogen-based silicone oil acting as a chain extender, 1.70-1.85 parts of end-side hydrogen-based silicone oil acting as a cross-linking agent, 0.10-0.20 parts of inhibitors, and 0.20-0.30 parts of surface functionalized nano-inorganic fillers.

5. The high temperature resistant silicone gel for IGBT encapsulation according to claim 4, characterized in that: The molar ratio of Si-H and Si-Vi in the high temperature resistant silicone gel for IGBT packaging is (0.43-0.52):

1.

6. The high temperature resistant silicone gel for IGBT encapsulation according to claim 1, characterized in that: The vinyl-terminated silicone oil in component A contains 40-60 wt % of vinyl-capped polysiloxane containing benzene rings in its molecular chain.

7. The high temperature resistant silicone gel for IGBT encapsulation according to claim 1, characterized in that: The double-terminal hydrogen-based silicone oil in component B, which acts as a chain extender, contains 40-60 wt % of double-terminal hydrogen-based terminated polysiloxane whose molecular chain contains benzene rings.

8. The high temperature resistant silicone gel for IGBT encapsulation according to claim 1, characterized in that: The vinyl-terminated silicone oil in component A contains 25-30 wt% of vinyl-capped polysiloxane with benzene rings in its molecular chain, and the double-terminated hydrogen-based silicone oil in component B that acts as a chain extender contains 20-40 wt% of double-terminated hydrogen-capped polysiloxane with benzene rings in its molecular chain.

9. The high temperature resistant silicone gel for IGBT encapsulation according to claim 7, characterized in that: The inhibitor is at least one of 1-ethynylcyclohexanol, (S)-5-phenyl-1-pentyn-3-ol, 3-octyl-1-butyn-3-ol, and 3-methyl-1-butyn-3-ol.

10. A method for preparing the high temperature resistant organic silicone gel for IGBT encapsulation according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: preparation of component A: uniformly mixing accurately measured vinyl-terminated silicone oil and monovinyl-terminated silicone oil, adding accurately measured platinum catalyst, stirring evenly and performing vacuum degassing to obtain component A; preparation of component B: first preparing surface functionalized nanometer inorganic filler, then uniformly mixing vinyl-terminated silicone oil, double-terminated hydrogen-based silicone oil, side-terminated hydrogen-based silicone oil, inhibitor and surface functionalized nanometer inorganic filler, and performing vacuum degassing to obtain component B; when using, uniformly mixing component A and component B at a mass ratio of 1:(0.65-1) to obtain a finished high-temperature resistant organic silicone gel.

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