Two-component double-curing heat-conducting pouring adhesive for micro power supply and preparation method thereof

Abstract

The application discloses a two-component double-curing heat-conducting pouring adhesive for a micro power supply, which is composed of A component and B component with a mass ratio of 90-110:16; the A component comprises 15-40 parts of silane modified polymer, 1-5 parts of an epoxy curing agent, 1-5 parts of a first diluent, 0.1-0.5 parts of a dispersing agent, 0.5-2 parts of an antifoaming agent, 25-50 parts of a first heat-conducting filler, 3-8 parts of a second heat-conducting filler, 15-35 parts of a flame retardant, 0.8-2 parts of a coupling agent and 0.05-0.2 parts of a catalyst; and the B component comprises 55-85 parts of an epoxy resin, 10-30 parts of a second diluent, 1-3 parts of a solubilizer and 0.5-2 parts of deionized water. The silane modified polymer, the epoxy curing agent, the first heat-conducting filler and the second heat-conducting filler are used as main agents, and the epoxy resin is used as a curing agent, so that a two-component double-curing system is formed, the pouring adhesive is suitable for micro power supply pouring and is suitable for pouring of housings made of various materials.

Description

Technical Field

[0001] This invention relates to the field of potting compound technology, specifically to a two-component, dual-curing, thermally conductive potting compound for micro power supplies and its preparation method. Background Technology

[0002] Power modules are indispensable components in electronic devices, providing a stable power supply to ensure normal operation. Thermally conductive potting compound is a crucial part of power modules, effectively improving their heat dissipation performance and ensuring long-term stable operation. In power modules, thermally conductive potting compound is primarily used to fix the components and ensure a tight bond between the components and the heatsink, improving heat dissipation. Some applications require high-temperature resistance, preventing shell detachment and cracking under high temperatures. Electronic products are rapidly developing towards miniaturization and multifunctionality, and the power modules used in these products are becoming increasingly powerful and smaller in size, reflecting the overall design of the products. To adapt to market demands, the requirements for thermally conductive potting compound used in miniaturized power supply packaging are becoming increasingly stringent in terms of heat dissipation, waterproofing, temperature resistance, and adhesion to the potting shell.

[0003] Currently, there are three types of power supply potting compounds on the market: silicone potting compounds, polyurethane potting compounds, and epoxy potting compounds. Silicone potting compounds offer good temperature resistance, moderate hardness, and good elasticity, and are reworkable. However, without pretreatment of the casing, addition-type silicone potting compounds have poor adhesion to the casing substrate, posing a potential waterproofing issue. Oxime-based two-component potting compounds have good adhesion to the casing, but release small molecules with a strong odor during curing, causing some pollution to the construction environment. Polyurethane potting compounds have moderate hardness and good adhesion to the casing, but poor long-term high-temperature resistance. Furthermore, the main component of the polyurethane potting compound curing agent is isocyanate, which poses certain health risks. Epoxy potting compounds have good bonding properties, but their overall hardness is high, resulting in poor resistance to deformation. Under high-temperature environments, the potted components are prone to casing deformation and cracking, and their high strength also leads to poor reworkability. Therefore, currently available thermally conductive potting compounds cannot simultaneously meet the requirements of high heat dissipation, waterproofing, high-temperature resistance, and good adhesion. Summary of the Invention

[0004] To overcome the above-mentioned technical problems, this invention discloses a two-component, dual-curing, thermally conductive potting compound for micro power supplies and its preparation method.

[0005] The technical solution adopted by the present invention to achieve the above objectives is as follows:

[0006] A two-component, dual-curing, thermally conductive potting compound for a micro power supply, wherein the potting compound is composed of component A and component B in a mass ratio of 90-110:16; wherein, by mass parts,

[0007] Component A comprises the following components: 15-40 parts silane-modified polymer, 1-5 parts epoxy curing agent, 1-5 parts first diluent, 0.1-0.5 parts dispersant, 0.5-2 parts defoamer, 25-50 parts first thermally conductive filler, 3-8 parts second thermally conductive filler, 15-35 parts flame retardant, 0.8-2 parts coupling agent, and 0.05-0.2 parts catalyst;

[0008] Component B consists of the following components: 55-85 parts epoxy resin, 10-30 parts second diluent, 1-3 parts solubilizer and 0.5-2 parts deionized water.

[0009] The aforementioned two-component, dual-curing, thermally conductive potting compound for micro power supplies is composed of component A and component B in a mass ratio of 90–110:16; wherein, by mass parts,

[0010] Component A comprises the following components: 15-40 parts of silane-modified polymer with a water content of less than 500 ppm, 1-5 parts of epoxy curing agent with a water content of less than 500 ppm, 1-5 parts of first diluent with a water content of less than 500 ppm, 0.1-0.5 parts of dispersant, 0.5-2 parts of defoamer, 25-50 parts of first thermally conductive filler with a water content of less than 3000 ppm, 3-8 parts of second thermally conductive filler with a water content of less than 3000 ppm, 15-35 parts of flame retardant with a water content of less than 2000 ppm, 0.8-2 parts of coupling agent, and 0.05-0.2 parts of catalyst;

[0011] Component B consists of the following components: 55-85 parts of epoxy resin with a water content of less than 500 ppm, 10-30 parts of a second diluent with a water content of less than 500 ppm, 1-3 parts of a solubilizer with a water content of less than 500 ppm, and 0.5-2 parts of deionized water.

[0012] The above-mentioned two-component, dual-curing, thermally conductive potting compound for micro power supplies, wherein the active group of the silane-modified polymer is methoxy or ethoxy, the molecular weight is 5000-30000, and the functionality is 2-3.

[0013] Optionally, the silane-modified polymer includes at least one of Zhongyuan Chemical S203H, SAX350, MAX951, Ruiyang Litai 201S, and Wacker STP-E10.

[0014] The aforementioned two-component, dual-curing, thermally conductive potting compound for micro power supplies, wherein the first thermally conductive filler comprises at least one of spherical alumina with a D50 of 20 micrometers, spherical silica with a D50 of 40 micrometers, and aluminum hydroxide with a D50 of 40 micrometers.

[0015] The aforementioned two-component, dual-curing, thermally conductive potting compound for micro power supplies, wherein the second thermally conductive filler comprises at least one of boron nitride GBN-60 with a D50 of 60 micrometers, active boron nitride GBN-60H48 with a D50 of 60 micrometers, and spherical aluminum nitride with a D50 of 60 micrometers.

[0016] The aforementioned two-component, dual-curing, thermally conductive potting compound for micro power supplies contains a coupling agent, Jiangsu Chenguang KH560, with a purity of 97%, 98%, or 99%.

[0017] The aforementioned two-component, dual-curing, thermally conductive potting compound for micro power supplies, wherein the second diluent is at least one of Eastman TXIB, Aladdin benzyl alcohol, Haierma modified epoxidized soybean oil T165, and Lanxess T50;

[0018] The solubilizer is polysorbate-20 from Haian Petrochemical in Jiangsu Province.

[0019] A method for preparing a two-component, dual-curing, thermally conductive potting compound for a micro power supply, wherein the method is used to prepare the aforementioned two-component, dual-curing, thermally conductive potting compound for a micro power supply.

[0020] The preparation method includes the following steps:

[0021] Step 1, Preparation of Component A: The silane-modified polymer, epoxy curing agent, first diluent, dispersant, defoamer, first thermally conductive filler, second thermally conductive filler, flame retardant, coupling agent and catalyst are added sequentially and stirred to disperse evenly to obtain Component A;

[0022] Step 2, Preparation of component B: The second diluent, solubilizer, deionized water and epoxy resin are added sequentially, stirred and dispersed evenly, and degassed under vacuum to obtain component B;

[0023] Step 3, prepare a two-component, dual-curing, thermally conductive potting compound for a micro power supply: mix component A and component B in a mass ratio of 90-110:16 to obtain the potting compound.

[0024] The above-mentioned method for preparing a two-component, dual-curing, thermally conductive potting compound for micro power supplies, wherein step 1 specifically includes the following steps:

[0025] Step 1-1: Mix the silane-modified polymer, epoxy curing agent, first diluent, dispersant and defoamer, and stir at 10 rpm for 10 min.

[0026] Steps 1-2: Add the first thermally conductive filler, the second thermally conductive filler and the flame retardant. Stir at 40 rpm and disperse at 800 rpm while heating to 105-110°C. Stir and disperse evenly under vacuum conditions below -0.098 MPa.

[0027] Steps 1-3: Cool down to below 60°C, add the coupling agent and catalyst, and stir evenly at a stirring speed of 40 rpm under a vacuum condition below -0.098 MPa to obtain component A.

[0028] The preparation method of the above-mentioned two-component dual-curing thermally conductive potting compound for micro power supplies, wherein step 2 specifically includes the following steps:

[0029] Step 2-1: Mix the second diluent, solubilizer and deionized water, and heat to 45-50°C while stirring at 10 rpm.

[0030] Step 2-2: Add the epoxy resin and heat it to 45-50°C while stirring at 40 rpm.

[0031] Steps 2-3: Cool down to 20-30℃, reduce the stirring speed to 10 rpm, turn on vacuum degassing, and degas under vacuum conditions below -0.098 MPa for 10 minutes to obtain component B.

[0032] The beneficial effects of this invention include the following:

[0033] (1) The two-component dual-curing thermally conductive potting compound for micro power supply of the present invention uses silane modified polymer, epoxy curing agent, first thermally conductive filler and second thermally conductive filler as the main agent and epoxy resin as the curing agent to form a two-component dual-curing system, which is suitable for micro power supply potting, has wide adaptability to potting substrates, and is suitable for potting various shell substrates, solving the shortcomings of other single system application processes;

[0034] (2) The silane-modified polymer in the main agent, under the action of a catalyst, hydrolyzes and crosslinks with the water molecules in the curing agent to form an elastomer. At the same time, the epoxy curing agent in the main agent reacts with the epoxy resin in the curing agent to form a hard adhesive layer, achieving good high-temperature resistance. The silane-modified polymer has good elasticity after curing. No pretreatment of the shell is required during the potting process. No odor is generated during the curing process. It provides good adhesion and good resistance to deformation. After the potting adhesive is cured, the hardness is moderate, the adhesive layer has good elasticity, and it has good adhesion to the shell. It also has good high-temperature resistance and thermal conductivity. The flame retardant level can reach UL94 V-0. The waterproof performance can reach IP68. The thermal conductivity is greater than 0.8W / mK. It has excellent aging resistance. It can withstand 1000 cycles of high and low temperature impact from -40℃ to 85℃ without cracking or peeling. It can also be baked at 130℃ for 7 days without cracking or peeling. It is environmentally friendly and has extremely low odor.

[0035] (3) Since the cured potting compound contains epoxy groups and a lot of organosilicon components, the overall high temperature resistance of the potting compound is better than that of the polyurethane system. Although it contains high-strength epoxy groups, the main agent is innovatively made of silane-modified polymer, and the overall hardness of the potting compound is moderate, which can meet the rework requirements. It is significantly improved compared with the pure epoxy system.

[0036] (4) The silane-modified polymers selected are S203H, SAX350 and MX951 from Zhongyuan Chemical. Among them, the main chain structure of S203H is pure ether bond, which is highly flexible and reduces the hardness of the cured adhesive layer, thus meeting the requirements for rework. SAX350 has high activity and can meet the initial curing requirements. The main chain of MX951 contains a certain amount of acrylic acid structure, which provides a guarantee for bonding to substrates with smooth surfaces and low polarity, and improves the adaptability of the product to potting substrates.

[0037] (5) The first thermally conductive filler is made of spherical alumina with a D50 of 20 micrometers, spherical silicon dioxide with a D50 of 40 micrometers, and aluminum hydroxide with a D50 of 40 micrometers. The second thermally conductive filler is made of boron nitride GBN-60 with a D50 of 60 micrometers, active boron nitride GBN-60H48 with a D50 of 60 micrometers, and spherical aluminum nitride with a D50 of 60 micrometers. The resulting potting compound has a moderate viscosity and a thermal conductivity greater than 0.8 W / mK.

[0038] (6) The coupling agent used is KH560 with higher purity, so that the potting compound can achieve a good waterproof effect;

[0039] (7) The second diluent is preferably modified epoxidized soybean oil, which has good hydrophilicity, good storage stability with deionized water, and good compatibility with epoxy resin.

[0040] (8) The solubilizer can more efficiently distribute deionized water evenly in the modified epoxidized soybean oil, while also improving the compatibility and storage stability of component B. Detailed Implementation

[0041] The present invention will be further described below through specific embodiments, so as to make the technical solution of the present invention easier to understand and master, rather than to limit the present invention.

[0042] This invention provides a two-component, dual-curing, thermally conductive potting compound for a micro power supply. The potting compound is composed of component A and component B in a mass ratio of 90–110:16; wherein, by mass parts,

[0043] Component A comprises the following components: 15-40 parts silane-modified polymer, 1-5 parts epoxy curing agent, 1-5 parts first diluent, 0.1-0.5 parts dispersant, 0.5-2 parts defoamer, 25-50 parts first thermally conductive filler, 3-8 parts second thermally conductive filler, 15-35 parts flame retardant, 0.8-2 parts coupling agent, and 0.05-0.2 parts catalyst;

[0044] Component B consists of the following components: 55-85 parts epoxy resin, 10-30 parts second diluent, 1-3 parts solubilizer and 0.5-2 parts deionized water.

[0045] Preferably, the potting compound is composed of component A and component B in a mass ratio of 90-110:16; wherein, by mass parts,

[0046] Component A comprises the following components: 15-40 parts of silane-modified polymer with a water content of less than 500 ppm, 1-5 parts of epoxy curing agent with a water content of less than 500 ppm, 1-5 parts of first diluent with a water content of less than 500 ppm, 0.1-0.5 parts of dispersant, 0.5-2 parts of defoamer, 25-50 parts of first thermally conductive filler with a water content of less than 3000 ppm, 3-8 parts of second thermally conductive filler with a water content of less than 3000 ppm, 15-35 parts of flame retardant with a water content of less than 2000 ppm, 0.8-2 parts of coupling agent, and 0.05-0.2 parts of catalyst;

[0047] Component B consists of the following components: 55-85 parts of epoxy resin with a water content of less than 500 ppm, 10-30 parts of a second diluent with a water content of less than 500 ppm, 1-3 parts of a solubilizer with a water content of less than 500 ppm, and 0.5-2 parts of deionized water.

[0048] Preferably, the active group of the silane-modified polymer is methoxy or ethoxy, the molecular weight is 5000-30000, and the functionality is 2-3.

[0049] Optionally, the silane-modified polymer includes at least one of Zhongyuan Chemical S203H, SAX350, MAX951, Ruiyang Litai 201S, and Wacker STP-E10.

[0050] Preferably, the epoxy curing agent is at least one of Ancamine K54, Momentive A1120, Momentive A1110, and Momentive A1100;

[0051] The first diluent is at least one of Eastman TXIB, Aladdin benzyl alcohol, and BASF DINCH;

[0052] The dispersant is at least one of BYK110, BYK410, and silok7455;

[0053] The defoamer is at least one of BYK088, BYK1794, and BYK A530.

[0054] Preferably, the first thermally conductive filler includes at least one of the following: spherical alumina with a D50 of 20 micrometers from Jiangsu Lianrui, spherical silica with a D50 of 40 micrometers from Jiangsu Lianrui, and aluminum hydroxide with a D50 of 40 micrometers from Dongguan Dongchao.

[0055] The second thermally conductive filler includes at least one of the following: boron nitride GBN-60 with a D50 of 60 micrometers, active boron nitride GBN-60H48 with a D50 of 60 micrometers, and spherical aluminum nitride with a D50 of 60 micrometers from Bohuas Nanotechnology.

[0056] Preferably, the flame retardant includes at least one of Zhenjiang Xingxing flame retardant D50 of aluminum hypophosphite with a size of 2-3 microns and Lanxess IPPP50;

[0057] The coupling agent is Jiangsu Chenguang KH560, with a purity of 97%, 98%, or 99%.

[0058] The catalyst is at least one of Nitto Chemical U-220H and Shanghai Guoyao dibutyltin dilaurate.

[0059] Preferably, the epoxy resin is at least one of Kunshan Nanya 828 and Kemic E-55;

[0060] The second diluent is at least one of Eastman TXIB, Aladdin benzyl alcohol, Haierma modified epoxidized soybean oil T165, and Lanxess T50;

[0061] The solubilizer is polysorbate-20 (Tween-20) from Jiangsu Haian Petrochemical Co., Ltd.

[0062] The present invention also discloses a method for preparing a two-component, dual-curing, thermally conductive potting compound for a micro power supply, the method being used to prepare the above-mentioned two-component, dual-curing, thermally conductive potting compound for a micro power supply.

[0063] The preparation method includes the following steps:

[0064] Step 1, Preparation of Component A: The silane-modified polymer, epoxy curing agent, first diluent, dispersant, defoamer, first thermally conductive filler, second thermally conductive filler, flame retardant, coupling agent and catalyst are added sequentially and stirred to disperse evenly to obtain Component A;

[0065] Step 2, Preparation of component B: The second diluent, solubilizer, deionized water and epoxy resin are added sequentially, stirred and dispersed evenly, and degassed under vacuum to obtain component B;

[0066] Step 3, prepare a two-component, dual-curing, thermally conductive potting compound for a micro power supply: mix component A and component B in a mass ratio of 90-110:16 to obtain the potting compound.

[0067] Preferably, step 1 specifically includes the following steps:

[0068] Step 1-1: Mix the silane-modified polymer, epoxy curing agent, first diluent, dispersant and defoamer, and stir at 10 rpm for 10 min.

[0069] Steps 1-2: Add the first thermally conductive filler, the second thermally conductive filler and the flame retardant. Stir at 40 rpm and disperse at 800 rpm while heating to 105-110°C. Stir and disperse evenly under vacuum conditions below -0.098 MPa.

[0070] Steps 1-3: Cool down to below 60°C, add the coupling agent and catalyst, and stir evenly at a stirring speed of 40 rpm under a vacuum condition below -0.098 MPa to obtain component A.

[0071] Preferably, step 2 specifically includes the following steps:

[0072] Step 2-1: Mix the second diluent, solubilizer and deionized water, and heat to 45-50°C while stirring at 10 rpm.

[0073] Step 2-2: Add the epoxy resin and heat it to 45-50°C while stirring at 40 rpm.

[0074] Steps 2-3: Cool down to 20-30℃, reduce the stirring speed to 10 rpm, turn on vacuum degassing, and degas under vacuum conditions below -0.098 MPa for 10 minutes to obtain component B.

[0075] The preparation method according to the present invention is described in detail in the following examples:

[0076] Example 1:

[0077] This embodiment provides a two-component, dual-curing, thermally conductive potting compound for a miniature power supply, which is prepared by the following steps:

[0078] Step 1: Add 180g of SAX350 (450ppm water content), 60g of S203H (475ppm water content), 121.2g of MAX951 (480ppm water content), 24g of Ancamine K54 (400ppm water content), 24g of TXIB (450ppm water content), 3.6g of BYK 110, and 12g of BYK1794 to a dry and clean 2L dual planetary mixer in sequence, and stir at 10rpm for 10min.

[0079] Add 324g of spherical alumina with a water content of 1240ppm and a D50 of 20 microns, 42g of active boron nitride GBN-60H48 with a water content of 1620ppm and a D50 of 60 microns, and 396g of aluminum hypophosphite with a water content of 1450ppm and a D50 of 2 microns. Stir at 40 rpm and disperse at 800 rpm while heating to 110℃. Stir and disperse evenly under vacuum conditions below -0.098MPa.

[0080] The mixture was cooled to below 60°C, and 1.2g of U-220H and 12g of KH560 with a purity of 97% were added. The mixture was stirred at a speed of 40 rpm under a vacuum of below -0.098 MPa to obtain component A.

[0081] Step 2: Add 50.328g of modified epoxidized soybean oil T165 with a water content of 410ppm, 6.72g of solubilizer TWEEN-20 with a water content of 395ppm and 2.4g of deionized water to a 500ml dry and clean three-necked flask in sequence. Stir at 10rpm and heat to 45℃.

[0082] Add 180.552g of Kunshan Nanya 828 epoxy resin with a water content of 433ppm, and heat to 50℃ while stirring at 40rpm.

[0083] Cool down to 30°C, reduce the stirring speed to 10 rpm, turn on vacuum degassing, and degas under vacuum conditions below -0.098 MPa for 10 min to obtain component B;

[0084] Step 3: Mix component A and component B at a mass ratio of 100:16 to obtain the potting compound.

[0085] Example 2:

[0086] This embodiment provides a two-component, dual-curing, thermally conductive potting compound for a miniature power supply, which is prepared by the following steps:

[0087] Step 1: Add 180g of SAX350 (420ppm water content), 60g of S203H (455ppm water content), 121.2g of MAX951 (460ppm water content), 24g of Ancamine K54 (430ppm water content), 24g of TXIB (400ppm water content), 3.6g of BYK 110, and 12g of BYK1794 to a dry and clean 2L dual planetary mixer in sequence, and stir at 10rpm for 10min.

[0088] Add 324g of spherical alumina with a water content of 1200ppm and a D50 of 20 microns, 196g of aluminum hydroxide with a water content of 1250ppm and a D50 of 40 microns, 42g of active boron nitride GBN-60H48 with a water content of 1620ppm and a D50 of 60 microns, and 200g of aluminum hypophosphite with a water content of 1250ppm and a D50 of 2 microns. Stir at 40 rpm and disperse at 800 rpm while heating to 110°C. Stir and disperse evenly under vacuum conditions below -0.098 MPa.

[0089] The mixture was cooled to below 60°C, and 1.2g of U-220H and 12g of KH560 with a purity of 99% were added. The mixture was stirred at a speed of 40 rpm under a vacuum of below -0.098 MPa to obtain component A.

[0090] Step 2: Add 50.328g of modified epoxidized soybean oil T165 with a water content of 420ppm, 6.72g of solubilizer TWEEN-20 with a water content of 385ppm and 2.4g of deionized water to a 500ml dry and clean three-necked flask in sequence. Stir at 10rpm and heat to 45℃.

[0091] Add 180.552g of Kunshan Nanya 828 epoxy resin with a water content of 405ppm, and heat to 50℃ while stirring at 40rpm.

[0092] Cool down to 30°C, reduce the stirring speed to 10 rpm, turn on vacuum degassing, and degas under vacuum conditions below -0.098 MPa for 10 min to obtain component B;

[0093] Step 3: Mix component A and component B at a mass ratio of 100:16 to obtain the potting compound.

[0094] Example 3:

[0095] This embodiment provides a two-component, dual-curing, thermally conductive potting compound for a miniature power supply, which is prepared by the following steps:

[0096] Step 1: Add 210g of SAX350 (423ppm water content), 30g of S203H (405ppm water content), 121.2g of MAX951 (465ppm water content), 24g of Ancamine K54 (400ppm water content), 24g of TXIB (380ppm water content), 3.6g of BYK 110, and 12g of BYK1794 to a dry and clean 2L dual planetary mixer in sequence, and stir at 10rpm for 10min.

[0097] Add 324g of spherical alumina with a water content of 1200ppm and a D50 of 20 microns, 196g of aluminum hydroxide with a water content of 1550ppm and a D50 of 40 microns, 42g of active boron nitride GBN-60H48 with a water content of 1220ppm and a D50 of 60 microns, and 200g of aluminum hypophosphite with a water content of 1150ppm and a D50 of 3 microns. Stir at 40 rpm and disperse at 800 rpm while heating to 110°C. Stir and disperse evenly under vacuum conditions below -0.098 MPa.

[0098] The mixture was cooled to below 60°C, and 1.2g of U-220H and 12g of KH560 with a purity of 99% were added. The mixture was stirred at a speed of 40 rpm under a vacuum of below -0.098 MPa to obtain component A.

[0099] Step 2: Add 54.648g of modified epoxidized soybean oil T165 with a water content of 400ppm, 2.4g of solubilizer TWEEN-20 with a water content of 375ppm and 2.4g of deionized water to a 500ml dry and clean three-necked flask in sequence. Stir at 10rpm and heat to 45℃.

[0100] Add 180.552g of Kunshan Nanya 828 epoxy resin with a water content of 428ppm, and heat to 50℃ while stirring at 40rpm.

[0101] Cool down to 30°C, reduce the stirring speed to 10 rpm, turn on vacuum degassing, and degas under vacuum conditions below -0.098 MPa for 10 min to obtain component B;

[0102] Step 3: Mix component A and component B at a mass ratio of 100:16 to obtain the potting compound.

[0103] Example 4:

[0104] This embodiment provides a two-component, dual-curing, thermally conductive potting compound for a miniature power supply, which is prepared by the following steps:

[0105] Step 1: Add 180g of SAX350 (415ppm water content), 60g of S203H (435ppm water content), 121.2g of MAX951 (465ppm water content), 24g of Ancamine K54 (438ppm water content), 24g of TXIB (408ppm water content), 3.6g of BYK 110, and 12g of BYK1794 to a dry and clean 2L dual planetary mixer in sequence, and stir at 10rpm for 10min.

[0106] Add 324g of spherical alumina with a water content of 1280ppm and a D50 of 20 microns, 196g of aluminum hydroxide with a water content of 1350ppm and a D50 of 40 microns, 42g of active boron nitride GBN-60H48 with a water content of 1520ppm and a D50 of 60 microns, and 200g of aluminum hypophosphite with a water content of 1200ppm and a D50 of 3 microns. Stir at 40 rpm and disperse at 800 rpm while heating to 105℃ and stirring and dispersing under vacuum conditions below -0.098MPa until uniformly dispersed.

[0107] The mixture was cooled to below 60°C, and 1.2g of U-220H and 12g of KH560 with a purity of 99% were added. The mixture was stirred at a speed of 40 rpm under a vacuum of below -0.098 MPa to obtain component A.

[0108] Step 2: Add 50.328g of epoxidized soybean oil with a water content of 411ppm, 6.72g of solubilizer TWEEN-20 with a water content of 415ppm and 2.4g of deionized water to a 500ml dry and clean three-necked flask. Stir at 10rpm and heat to 50℃.

[0109] Add 180.552g of Kunshan Nanya 828 epoxy resin with a water content of 445ppm, and heat to 50℃ while stirring at 40rpm.

[0110] Cool down to 20°C, reduce the stirring speed to 10 rpm, turn on vacuum degassing, and degas under vacuum conditions below -0.098 MPa for 10 min to obtain component B;

[0111] Step 3: Mix component A and component B at a mass ratio of 100:16 to obtain the potting compound.

[0112] Samples of the two-component, dual-curing, thermally conductive potting compound for the micro power supply prepared in Examples 1-4 were prepared, and basic performance parameters were measured. Detailed test results are shown in Table 1.

[0113] Table 1 Results of Basic Performance Parameter Measurement

[0114]

[0115]

[0116] The experimental results show that:

[0117] (1) The potting compound experimental samples of Examples 1 to 4 had no obvious odor;

[0118] (2) As can be seen from the comparison between Example 1 and Examples 2-4, the combination of the first thermally conductive filler and the second thermally conductive filler is crucial. The combination of 20-micron spherical alumina, 60-micron spherical aluminum nitride and 40-micron aluminum hydroxide can achieve a moderate viscosity and a thermal conductivity of more than 0.8 W / mK in the potting compound test sample.

[0119] (3) As can be seen from the comparison between Example 1 and Examples 2-4, the purity of the coupling agent has a significant impact on the waterproof performance of the cured potting compound test sample. The higher the purity, the better the waterproof performance. Using KH560 with a purity of 99%, the waterproof rating of the potting compound test sample can reach IP68.

[0120] (4) As can be seen from the comparison between Example 2 and Example 3, the amount of solubilizer added has a significant impact on the storage stability of component B. When the amount added is 6.72g, the reaction system has good homogeneity and no turbidity is observed after 7 days of standing at room temperature.

[0121] (5) As can be seen from the comparison between Example 2 and Example 4, the use of modified epoxidized soybean oil in component B has a significant effect on improving the compatibility and stability of the reaction system.

[0122] (6) The potting adhesive test samples of Examples 1 to 4 showed good adhesion to 3003 series aluminum alloy and PA. After baking at 130°C for 7 days, there were no abnormalities in appearance.

[0123] (7) Based on the above embodiments, it can be concluded that the comprehensive performance of Example 2 is the best. It has no odor during the curing process, moderate viscosity, good compatibility of component B, good stability, thermal conductivity above 0.8W / mK, good adhesion to 3003 series aluminum materials and PA, waterproof rating of IP68, and no abnormal appearance after baking at 130℃ for 7 days.

[0124] The two-component, dual-curing, thermally conductive potting compound for miniature power supplies of the present invention has the following advantages:

[0125] (1) The two-component dual-curing thermally conductive potting compound for micro power supply of the present invention uses silane modified polymer, epoxy curing agent, first thermally conductive filler and second thermally conductive filler as the main agent and epoxy resin as the curing agent to form a two-component dual-curing system, which is suitable for micro power supply potting, has wide adaptability to potting substrates, and is suitable for potting various shell substrates, solving the shortcomings of other single system application processes;

[0126] (2) The silane-modified polymer in the main agent, under the action of a catalyst, hydrolyzes and crosslinks with the water molecules in the curing agent to form an elastomer. At the same time, the epoxy curing agent in the main agent reacts with the epoxy resin in the curing agent to form a hard adhesive layer, achieving good high-temperature resistance. The silane-modified polymer has good elasticity after curing. No pretreatment of the shell is required during the potting process. No odor is generated during the curing process. It provides good adhesion and good resistance to deformation. After the potting adhesive is cured, the hardness is moderate, the adhesive layer has good elasticity, and it has good adhesion to the shell. It also has good high-temperature resistance and thermal conductivity. The flame retardant level can reach UL94 V-0. The waterproof performance can reach IP68. The thermal conductivity is greater than 0.8W / mK. It has excellent aging resistance. It can withstand 1000 cycles of high and low temperature impact from -40℃ to 85℃ without cracking or peeling. It can also be baked at 130℃ for 7 days without cracking or peeling. It is environmentally friendly and has extremely low odor.

[0127] (3) Since the cured potting compound contains epoxy groups and a lot of organosilicon components, the overall high temperature resistance of the potting compound is better than that of the polyurethane system. Although it contains high-strength epoxy groups, the main agent is innovatively made of silane-modified polymer, and the overall hardness of the potting compound is moderate, which can meet the rework requirements. It is significantly improved compared with the pure epoxy system.

[0128] (4) The silane-modified polymers selected are S203H, SAX350 and MX951 from Zhongyuan Chemical. Among them, the main chain structure of S203H is pure ether bond, which is highly flexible and reduces the hardness of the cured adhesive layer, thus meeting the requirements for rework. SAX350 has high activity and can meet the initial curing requirements. The main chain of MX951 contains a certain amount of acrylic acid structure, which provides a guarantee for bonding to substrates with smooth surfaces and low polarity, and improves the adaptability of the product to potting substrates.

[0129] (5) The first thermally conductive filler is made of spherical alumina with a D50 of 20 micrometers, spherical silicon dioxide with a D50 of 40 micrometers, and aluminum hydroxide with a D50 of 40 micrometers. The second thermally conductive filler is made of boron nitride GBN-60 with a D50 of 60 micrometers, active boron nitride GBN-60H48 with a D50 of 60 micrometers, and spherical aluminum nitride with a D50 of 60 micrometers. The resulting potting compound has a moderate viscosity and a thermal conductivity greater than 0.8 W / mK.

[0130] (6) The coupling agent used is KH560 with higher purity, so that the potting compound can achieve a good waterproof effect;

[0131] (7) The second diluent is preferably modified epoxidized soybean oil, which has good hydrophilicity, good storage stability with deionized water, and good compatibility with epoxy resin.

[0132] (8) The solubilizer can more efficiently distribute deionized water evenly in the modified epoxidized soybean oil, while also improving the compatibility and storage stability of component B.

[0133] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any person skilled in the art can make many possible variations and modifications to the technical solution of the present invention, or modify it into equivalent embodiments, without departing from the scope of the present invention, using the disclosed technical means and content. Therefore, all equivalent changes made based on the shape, structure, and principle of the present invention without departing from the scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A two-component dual-cure thermal conductive potting adhesive for micro power supply, characterized in that, The potting glue is composed of A component and B component in a mass ratio of 90-110:16; wherein, in terms of mass fraction, The A component is composed of 15-40 parts of silane modified polymer, 1-5 parts of epoxy curing agent, 1-5 parts of first diluent, 0.1-0.5 parts of dispersant, 0.5-2 parts of defoaming agent, 25-50 parts of first thermal conductive filler, 3-8 parts of second thermal conductive filler, 15-35 parts of flame retardant, 0.8-2 parts of coupling agent and 0.05-0.2 parts of catalyst; The B component is composed of 55-85 parts of epoxy resin, 10-30 parts of second diluent, 1-3 parts of solubilizer and 0.5-2 parts of deionized water; The second diluent is at least one of Eastman TXIB, Araldite benzyl alcohol, Hailma modified epoxy soybean oil T165 and Lonza T50; The solubilizer is Jiangsu Hainan Petrochemical Polysorbate-20.

2. The two-component dual-cure thermal conductive potting adhesive for micro power supply according to claim 1, characterized in that, The potting glue is composed of A component and B component in a mass ratio of 90-110:16; wherein, in terms of mass fraction, The A component is composed of 15-40 parts of silane modified polymer, 1-5 parts of epoxy curing agent, 1-5 parts of first diluent, 0.1-0.5 parts of dispersant, 0.5-2 parts of defoaming agent, 25-50 parts of first thermal conductive filler, 3-8 parts of second thermal conductive filler, 15-35 parts of flame retardant, 0.8-2 parts of coupling agent and 0.05-0.2 parts of catalyst; The B component is composed of 55-85 parts of epoxy resin, 10-30 parts of second diluent, 1-3 parts of solubilizer and 0.5-2 parts of deionized water.

3. The two-component dual-cure thermal conductive potting adhesive for micro power supply according to claim 2, characterized in that, The active group of the silane modified polymer is methoxy or ethoxy, the molecular weight is 5000-30000, and the functionality is 2-3; Optionally, the silane modified polymer includes at least one of Zhongjian Chemical S203H, SAX350, MAX951, Ruoyang Litai 201S and Wacker STP-E10.

4. The two-component dual-cure thermal conductive potting adhesive for micro power supply according to claim 3, characterized in that, The first thermal conductive filler includes at least one of spherical alumina with a D50 of 20 microns, spherical silica with a D50 of 40 microns and aluminum hydroxide with a D50 of 40 microns.

5. The two-component dual-cure thermal conductive potting adhesive for micro power supply according to claim 4, characterized in that, The second thermal conductive filler includes at least one of boron nitride GBN-60 with a D50 of 60 microns, active boron nitride GBN-60H48 with a D50 of 60 microns and spherical aluminum nitride with a D50 of 60 microns.

6. The two-component dual-cure thermal conductive potting adhesive for micro power supply according to claim 5, characterized in that, The coupling agent is Jiangsu Chen Guang KH560 with a purity of one of 97%, 98% and 99%.

7. A method for preparing a two-component dual-cure thermal conductive encapsulant for micro power supply, characterized in that, The preparation method is used for preparing the two-component double-curing thermal conductive potting glue for micro power supply according to any one of claims 1-6; The preparation method includes the following steps: Step 1, preparing A component: sequentially adding the silane-modified polymer, epoxy curing agent, first diluent, dispersant, defoaming agent, first thermal conductive filler, second thermal conductive filler, flame retardant, coupling agent and catalyst, stirring and uniformly dispersing to obtain the A component; Step 2, preparing B component: sequentially adding the second diluent, solubilizer, deionized water and epoxy resin, stirring and uniformly dispersing, vacuum degassing to obtain the B component; Step 3, preparing two-component double-curing thermal conductive pouring sealant for micro power supply: mixing the A component and B component in a mass ratio of 90-110:16 to obtain the pouring sealant.

8. The method for preparing the two-component dual-curing thermal conductive pouring sealant for micro power supply according to claim 7, characterized in that, The step 1 specifically comprises the following steps: Step 1-1, mixing the silane-modified polymer, epoxy curing agent, first diluent, dispersant and defoaming agent, stirring at a stirring speed of 10 rpm for 10 min; Step 1-2, adding the first thermal conductive filler, second thermal conductive filler and flame retardant, stirring and dispersing at a stirring speed of 40 rpm and a dispersing speed of 800 rpm, heating to 105-110°C, and stirring and uniformly dispersing under a vacuum condition of less than -0.098 MPa; Step 1-3, cooling to below 60°C, adding the coupling agent and catalyst, stirring uniformly under a vacuum condition of less than -0.098 MPa at a stirring speed of 40 rpm to obtain the A component.

9. The method for preparing the two-component dual-curing thermal conductive pouring sealant for micro power supply according to claim 7, characterized in that, The step 2 specifically comprises the following steps: Step 2-1, mixing the second diluent, solubilizer and deionized water, stirring at a stirring speed of 10 rpm and heating to 45-50°C; Step 2-2, adding the epoxy resin, stirring at a stirring speed of 40 rpm and heating to 45-50°C; Step 2-3, cooling to 20-30°C, reducing the stirring speed to 10 rpm, opening the vacuum degassing, vacuum degassing under a vacuum condition of less than -0.098 MPa for 10 min to obtain the B component.

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