Powder treating agent, preparation method and application thereof, high-strength heat-resistant anti-cracking organosilicone heat-conducting pouring sealant and preparation method thereof

Abstract

The invention belongs to the field of bi-component organosilicone heat-conducting pouring sealant materials, and provides a powder treating agent, a preparation method and application thereof, a high-strength heat-resistant anti-cracking organosilicone heat-conducting pouring sealant and a preparation method thereof, and the high-strength heat-resistant anti-cracking organosilicone heat-conducting pouring sealant is composed of a component A and a component B according to the mass ratio of 1: 1. The component A is composed of vinyl silicone oil, a powder treating agent H, hydrogen-containing silicone oil, an inhibitor and a heat-conducting filler; and the component B is composed of vinyl silicone oil, a powder treating agent H, a catalyst, a pigment and a heat-conducting filler. The heat conduction coefficient of the heat conduction pouring sealant is larger than 1.5 W / (m.k), the viscosity is smaller than 5000 mPa.s, the average linear expansion coefficient is smaller than 120 [mu] m / (m.DEG C), the tensile strength is larger than 3.0 MPa, the elongation at break is larger than 100%, and the problem that the high heat conduction pouring sealant is prone to bulging and cracking after being aged at high temperature can be effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of two-component organic silicon thermal conductive potting adhesive materials, and in particular to a powder treating agent, a preparation method and application thereof, a high-strength, heat-resistant and crack-resistant organic silicon thermal conductive potting adhesive and a preparation method thereof. Background Art

[0002] Thermal conductive potting glue has a certain fluidity. Low-viscosity thermal conductive potting glue has good fluidity, is easy to pour, and can better penetrate into the gaps of electronic components to ensure good protection. At the same time, appropriate viscosity also helps to form a uniform coating and ensure stable performance after curing. Therefore, when preparing thermal conductive potting glue, it is necessary to examine the viscosity of the thermal conductive potting glue so that the thermal conductive potting glue meets the needs of the application scenario.

[0003] Power supply systems often face extreme environments such as high temperature and high humidity. Traditional power supply casing potting compounds often face challenges such as expansion, decreased thermal conductivity, weakened mechanical strength, and cracking in these extreme environments. This not only affects heat dissipation efficiency, but can also lead to electrical failures due to water vapor penetration caused by cracking, resulting in current leakage and short circuits, seriously threatening equipment safety. Therefore, when developing silicone potting compounds, their heat aging resistance and cracking resistance are equally important.

[0004] With the rapid development of high-tech sectors such as 5G communications, new energy vehicles, and aerospace, the requirements for power supply systems are becoming increasingly stringent. As the heart of a device, the stability and reliability of the power supply are directly related to the overall system's operational efficiency and safety. However, as electronic devices move toward miniaturization, integration, and high power density, thermal management within the power supply housing has become increasingly prominent, becoming a bottleneck restricting technological progress. Thermal conductivity, which reflects the thermal conductivity of a potting compound, is a key performance consideration when developing silicone potting compounds. Currently, some excellent potting compounds have a thermal conductivity of ≥1.5W / (m·k).

[0005] The linear expansion coefficient is a crucial parameter in evaluating potting compound performance. Excessively high linear expansion can lead to the compound losing its performance in high-temperature environments, severely impacting the equipment's operating efficiency and lifespan. Therefore, reducing the linear expansion coefficient is a research goal for silicone potting compounds. Chinese patent application publication number CN111808571A discloses a highly thermally conductive silicone potting compound specifically for photovoltaic inverters. This potting compound exhibits a thermal conductivity ≥1.5 W / (m·K) but a linear expansion coefficient >150 μm / (m·°C). This compound is susceptible to expansion during aging in high-temperature environments, potentially squeezing and damaging electronic components.

[0006] While increasing the hardness of thermally conductive potting compounds can effectively reduce the linear expansion coefficient, excessive hardness can degrade the compound's mechanical properties. Because equipment operation can cause vibrations in the housing, prolonged operation of a thermally conductive potting compound with excessive hardness can damage components within the housing and generate significant noise. Therefore, appropriate hardness is a crucial property of thermally conductive potting compounds when used for housing potting.

[0007] Among the various properties mentioned above, thermal conductivity and viscosity are the primary performance considerations for potting compounds currently on the market. However, for power module potting, the mechanical properties of silicone potting compounds (such as tensile strength and elongation at break) are becoming increasingly important due to increasingly demanding application conditions. Chinese patent publication number CN116554834A proposes a method for enhancing the strength of a colloid. While the tensile strength reaches 4.0 MPa, the elongation at break is low (only 70%), resulting in poor toughness. Furthermore, the filler used in this method, which contains modified cellulose nanowhiskers, exhibits good electrical conductivity but poor volume resistivity, making it unsuitable for potting the housings of devices containing electronic integrated circuits, such as power inductors.

[0008] Because potting compounds require consideration of multiple parameters, including viscosity, heat aging resistance, thermal conductivity, linear expansion coefficient, hardness, and mechanical properties, these parameters often exhibit trade-offs. While ensuring that viscosity, heat aging resistance, thermal conductivity, and hardness meet the requirements for potting enclosures containing electronic integrated circuits, reducing the linear expansion coefficient and improving mechanical properties are key approaches to addressing the problem of bulging and cracking caused by prolonged high-temperature exposure. Summary of the Invention

[0009] In response to the shortcomings of the existing technology, the present invention provides a powder treatment agent and its preparation method and application, a high-strength, heat-resistant and crack-resistant silicone thermal conductive potting glue and its preparation method, aiming to solve the problem that the glue is prone to expansion, bulging and cracking in a long-term high-temperature environment.

[0010] The first object of the present invention is to provide a high-strength, heat-resistant and crack-resistant organic silicon thermally conductive potting adhesive. The thermally conductive potting adhesive is a two-component adhesive consisting of component A and component B.

[0011] Optionally, the high-strength, heat-resistant, and crack-resistant organic silicone thermally conductive potting adhesive is made of the following materials, measured in parts by mass:

[0012] Component A

[0013]

[0014] Component B

[0015]

[0016] Optionally, component B further includes 0.1 to 0.5 parts of a pigment. When a pigment is used in component B, component B is made of raw materials including the following materials:

[0017]

[0018] Optionally, the viscosity of the vinyl silicone oil in components A and B is 100 to 500 mPa·s; preferably, the viscosity of the vinyl silicone oil is 100 to 300 mPa·s. The viscosity of the vinyl silicone oil in components A and B can be the same or different. The vinyl content of the vinyl silicone oil is 0.1% to 1.5%.

[0019] Optionally, the thermally conductive fillers in components A and B are compounded from one or more of alumina, silica powder, aluminum hydroxide, and magnesium hydroxide of varying particle sizes and morphologies, with a powder particle size of 1 to 80 μm, preferably 1 to 40 μm. The thermally conductive fillers used in components A and B may be the same or different.

[0020] Optionally, the powder treating agent H has the following structural formula:

[0021] n is an integer from 1 to 50;

[0022] Wherein, the structure of R1 is selected from any one of the following structures:

[0023]

[0024] a is an integer of 6-20, and b is an integer of 1-3.

[0025] In the structural formula of the powder treating agent H, n being an integer of 1 to 50 means that n can be 1, 50 or any other number between 1 and 50, such as 5, 10, 15, 20, 25, 30, 35, 40, 45, etc.; a being an integer of 6 to 20 means that a is 6, 20 or any other number between 6 and 20, such as 10, 12, 15, 18, etc.; b being an integer of 1 to 3 means that b is 1, 2 or 3.

[0026] The preparation method of the powder treating agent H comprises the following steps:

[0027] (1) Stir the end-hydrogenated silicone oil and platinum catalyst evenly;

[0028] (2) heating to 80°C to 90°C in a nitrogen atmosphere, adding 1,1-bis(trimethoxysilylmethyl)ethylene dropwise, and stirring the reaction for 60 to 90 minutes;

[0029] (3) cooling and removing unreacted raw materials to obtain auxiliary agent S1;

[0030] (4) Stirring the auxiliary agent S2 and the platinum catalyst evenly, heating to 80°C to 90°C in a nitrogen atmosphere, adding the auxiliary agent S1 dropwise, and stirring the reaction for 60 to 90 minutes; the auxiliary agent S2 is selected from any one of 3,4,5-trivinylbenzene, triallyl (phenyl) silane, and T-type vinylphenyl silicone oil;

[0031] (5) cooling and removing unreacted raw materials;

[0032] (6) Add activated carbon, stir and adsorb, let it stand, and filter to remove the residual platinum catalyst to obtain powder treatment agent H.

[0033] Furthermore, in more detail, the preparation method of the powder treating agent H comprises the following steps:

[0034] (1) Add 0.12-0.36 mol of end-hydrogenated silicone oil and 0.2 g of 3000 ppm platinum catalyst into a three-necked flask and stir evenly;

[0035] (2) Heating to 80-90°C in a nitrogen atmosphere, adding 0.1-0.3 mol of the auxiliary agent 1,1-bis(trimethoxysilylmethyl)ethylene (Hubei Xinrunde Chemical Co., Ltd., CAS: 143727-20-2) dropwise, and stirring the reaction for 60-90 min;

[0036] (3) Cooling to 50° C. and distilling under reduced pressure to remove unreacted raw materials to obtain auxiliary agent S1;

[0037] (4) In another three-necked flask, 0.12-0.36 mol of auxiliary agent S2 and 0.2 g of platinum catalyst with a concentration of 3000 ppm were added, stirred evenly, heated to 80°C-90°C in a nitrogen atmosphere, and 0.1-0.3 mol of auxiliary agent S1 was added dropwise, and stirred for 60-90 min; auxiliary agent S2 was selected from any one of 1,3,5-trivinylbenzene (Henan Alpha Chemical Co., Ltd., CAS: 3048-52-0), triallyl (phenyl) silane (Henan Alpha Chemical Co., Ltd., CAS: 2633-57-0), and T-type vinylphenyl silicone oil;

[0038] (5) Cooling to 50° C. and distilling under reduced pressure to remove unreacted raw materials;

[0039] (6) Add activated carbon and stir for adsorption, let it stand for 24 hours, and filter to remove the residual platinum catalyst to obtain powder treatment agent H.

[0040] The structural formula of the auxiliary agent 1,1-bis(trimethoxysilylmethyl)ethylene is as follows:

[0041]

[0042] The structure of additive S2:

[0043] Triallyl(phenyl)silane (Henan Alpha Chemical Co., Ltd., CAS: 2633-57-0):

[0044]

[0045] 1,3,5-Trivinylbenzene (Henan Alpha Chemical Co., Ltd., CAS: 3048-52-0):

[0046]

[0047] T-type vinyl phenyl silicone oil (Anhui Aiyota Silicone Oil Co., Ltd.):

[0048]

[0049] (a=12, b=3, viscosity 500 mPa·s, vinyl content 5.41%).

[0050] Powder treatment agents prepared using different additives S2 and the above method for preparing powder treatment agent H include but are not limited to the following:

[0051]

[0052]

[0053] Optionally, the hydrogen-containing silicone oil described in component A is compounded from one or more hydrogen-containing silicone oils with a hydrogen content between 0.1% and 0.75%, including end hydrogen-containing silicone oil, side hydrogen-containing silicone oil and their compounds; preferably, the hydrogen content of the hydrogen-containing silicone oil described in component A is 0.1% to 0.5%.

[0054] Optionally, the inhibitor in component A is a compound of one or more of ethynylcyclohexanol, methylbutynol, and tetramethyltetravinylcyclotetrasiloxane; preferably, the inhibitor in component A is ethynylcyclohexanol.

[0055] Optionally, the catalyst in component B is a Custer platinum catalyst.

[0056] Optionally, the pigment in component B is iron black paste or carbon black paste.

[0057] A second object of the present invention is to provide a method for preparing a high-strength, heat-resistant, and crack-resistant organic silicone thermally conductive potting compound, the method comprising the following steps:

[0058] Preparation of component A:

[0059] (1) Add part of the vinyl silicone oil and all the powder treatment agent H into a double planetary mixer and mix them evenly;

[0060] (2) Raise the temperature to 100°C, add some thermal conductive filler and stir evenly;

[0061] (3) Add the remaining thermal conductive filler and stir evenly;

[0062] (4) Heating to 150°C, vacuuming and stirring;

[0063] (5) After cooling to room temperature, add the remaining vinyl silicone oil, all hydrogenated silicone oil, and all inhibitors, and stir under vacuum;

[0064] (6) vacuuming and stirring to obtain component A;

[0065] Preparation of component B:

[0066] (1) Add part of the vinyl silicone oil and all the powder treatment agent H into a double planetary mixer and mix them evenly;

[0067] (2) Raise the temperature to 100°C, add some thermal conductive filler and stir evenly;

[0068] (3) Add the remaining thermal conductive filler and pigment and stir evenly;

[0069] (4) Heating to 150°C, vacuuming and stirring;

[0070] (5) After cooling to room temperature, add the remaining vinyl silicone oil and all the catalysts, and stir under vacuum;

[0071] (6) Vacuum and stir to obtain component B.

[0072] In the present invention, room temperature refers to a temperature of 20 to 30° C., and generally refers to the natural ambient temperature without artificial heating or cooling.

[0073] Preferably, the present invention provides a method for preparing a high-strength, heat-resistant, and crack-resistant organic silicone thermally conductive potting adhesive, which has more detailed operating steps as follows:

[0074] Preparation of component A:

[0075] (1) Add vinyl silicone oil and powder treatment agent H into a double planetary mixer and stir for 2 minutes;

[0076] (2) Raise the temperature to 100°C, add 50% thermal conductive filler and stir for 10 minutes;

[0077] (3) Add the remaining 50% of thermal conductive filler and stir for 10 minutes;

[0078] (4) Heating to 150°C, vacuuming and stirring for 60 min;

[0079] (5) After cooling to room temperature, add hydrogenated silicone oil and inhibitor, and stir under vacuum for 30 minutes;

[0080] (6) Vacuum and stir for 15 min to obtain component A;

[0081] Preparation of component B:

[0082] (1) Add 50% to 80% of the calculated amount of vinyl silicone oil and powder treatment agent H into a double planetary mixer and stir for 2 minutes;

[0083] (2) Raise the temperature to 100°C, add 50% thermal conductive filler and stir for 10 minutes;

[0084] (3) Add the remaining 50% of thermal conductive filler and pigment and stir for 10 minutes;

[0085] (4) Heating to 150°C, vacuuming and stirring for 60 min;

[0086] (5) After cooling to room temperature, add the remaining vinyl silicone oil and catalyst and stir under vacuum for 30 minutes;

[0087] (6) Vacuum and stir for 15 minutes to obtain component B.

[0088] Furthermore, in the preparation method of the high-strength, heat-resistant and crack-resistant silicone thermally conductive potting glue, the vacuum pressure is set to less than -0.08MPa during vacuum stirring, and the vacuum pressure is set to less than -0.06MPa during vacuum stirring. The main stirring speed is 50±5r / min, and the dispersion disk speed is 300±20r / min.

[0089] Compared with the prior art, the present invention has at least the following beneficial effects:

[0090] 1. The organic silicone thermally conductive potting compound prepared by the present invention has a thermal conductivity coefficient greater than 1.5 W / (mK), a viscosity less than 5000 mPa·s, an average linear expansion coefficient less than 120 μm / (m·°C), a tensile strength greater than 3.0 MPa, and an elongation at break greater than 100%. While the viscosity, heat aging resistance, thermal conductivity, and hardness meet the requirements for potting of equipment housings containing electronic integrated circuits, the organic silicone thermally conductive potting compound reduces the linear expansion coefficient and improves the mechanical properties. The compound can effectively solve problems such as poor heat dissipation, expansion cracking, low strength, and increased noise caused by excessive hardness during use in power supplies, photovoltaic inverters, reactors, and the like.

[0091] 2. The powder treatment agent H used in the present invention contains six alkoxy groups with high hydrolysis activity at one end. The silanol formed after hydrolysis is more acidic than that of ordinary silane coupling agents, can form stronger covalent bonds and higher cross-linking density with the hydroxyl groups on the powder surface, and is not easily hydrolyzed, thereby increasing the compatibility of silicone oil and thermal conductive filler powder, promoting tighter bonding after colloid curing, and thus improving colloid strength; the other end of the powder treatment agent H contains a polyvinyl group, which can participate in the hydrosilylation reaction under a platinum catalyst. The polyvinyl structure can increase the cross-linking density between the powder and the main chain, thereby improving the colloid strength.

[0092] 3. The powder treatment agent H used in the present invention contains phenyl functional groups. When introduced into the silicone rubber's molecular chains, these groups disrupt the regularity of the dimethylsiloxane structure, restricting molecular motion and thus altering the intermolecular forces. This reduces the molecular chains from undergoing intense thermal motion and thermal degradation at high temperatures, thereby improving the rubber's heat resistance. The phenyl group has a certain electron cloud density, which to a certain extent hinders oxygen attack on the rubber's molecular chains, reducing the occurrence of oxidation reactions and thus improving the rubber's thermal oxidative stability. Furthermore, the addition of spherical silica powder filler, which has a low linear expansion coefficient, to the formula effectively reduces the colloidal linear expansion coefficient. DETAILED DESCRIPTION

[0093] In order to make the purpose, technical solutions and advantages of the present invention more clear and distinct, the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0094] 1. Preparation of powder treatment agent H

[0095] (1) Add 0.12 mol of end-hydrogenated silicone oil and 0.2 g of 3000 ppm platinum catalyst into a three-necked flask and stir evenly;

[0096] (2) heating to 80-90°C in a nitrogen atmosphere, adding 0.1 mol of the auxiliary agent 1,1-bis(trimethoxysilylmethyl)ethylene dropwise, and stirring the reaction for 30 min;

[0097] (3) Cooling to 50°C and distilling under reduced pressure to remove unreacted raw materials to prepare auxiliary agent S1;

[0098] (4) In another three-necked flask, add 0.12 mol of the additive S2 and 0.2 g of a platinum catalyst with a concentration of 3000 ppm and stir evenly;

[0099] (5) Heat to 80-90°C in a nitrogen atmosphere, add 0.1 mol of additive S1 dropwise, and stir for 30 min;

[0100] (6) removing unreacted raw materials by distillation under reduced pressure at 50°C;

[0101] (7) Add activated carbon and stir for adsorption, let it stand for 24 hours, and filter to remove the residual platinum catalyst to obtain powder treatment agent H.

[0102] The above preparation method can be used to obtain the powder treatment agents with the following structural formulas, which are used in the examples:

[0103] When the auxiliary agent S2 is triallyl(phenyl)silane, the powder treatment agent H1 is prepared;

[0104]

[0105] When the auxiliary agent S2 is 1,3,5-trivinylbenzene, the powder treatment agent H2 is prepared;

[0106]

[0107] When the auxiliary agent S2 is T-type vinylphenyl silicone oil, the powder treatment agent H3 is prepared;

[0108]

[0109] 2. Thermal conductive powder compounding:

[0110] 40 parts of 40μm spherical alumina, 20 parts of 40μm angular alumina, 58 parts of 40μm spherical silicon powder, 60 parts of 5μm spherical alumina, 2 parts of 1μm quasi-spherical alumina, and 20 parts of 40μm aluminum hydroxide (a total of 200 parts).

[0111] 3. Preparation of high-strength, heat-resistant and crack-resistant silicone thermal conductive potting glue

[0112] Example 1

[0113] Preparation of component A: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.8 parts of powder treatment agent H1 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 100 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 100 parts of thermal conductive filler and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%), 13 parts of end hydrogen-containing silicone oil (hydrogen content 0.1%), 1.2 parts of side hydrogen-containing silicone oil (hydrogen content 0.36%), and 0.06 parts of inhibitor, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component A.

[0114] Preparation of component B: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.8 parts of powder treatment agent H1 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 100 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 100 parts of thermal conductive filler and 0.2 parts of pigment and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%) and 0.1 parts of catalyst, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component B.

[0115] Example 2

[0116] Preparation of component A: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.8 parts of powder treatment agent H2 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 100 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 100 parts of thermal conductive filler and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%), 13 parts of end hydrogen-containing silicone oil (hydrogen content 0.1%), 1.2 parts of side hydrogen-containing silicone oil (hydrogen content 0.36%), and 0.06 parts of inhibitor, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component A.

[0117] Preparation of component B: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.8 parts of powder treatment agent H2 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 100 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 100 parts of thermal conductive filler and 0.2 parts of pigment and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%) and 0.1 parts of catalyst, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component B.

[0118] Example 3

[0119] Preparation of component A: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.8 parts of powder treatment agent H3 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 100 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 100 parts of thermal conductive filler and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%), 13 parts of end hydrogen-containing silicone oil (hydrogen content 0.1%), 1.3 parts of side hydrogen-containing silicone oil (hydrogen content 0.36%), and 0.06 parts of inhibitor, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component A.

[0120] Preparation of component B: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.8 parts of powder treatment agent H3 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 100 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 100 parts of thermal conductive filler and 0.2 parts of pigment and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%) and 0.1 parts of catalyst, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component B.

[0121] Example 4

[0122] Preparation of component A: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.2 parts of powder treatment agent H1 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 80 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 120 parts of thermal conductive filler and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%), 12 parts of end hydrogen-containing silicone oil (hydrogen content 0.1%), 1.2 parts of side hydrogen-containing silicone oil (hydrogen content 0.36%), and 0.01 parts of inhibitor, and stir in a vacuum for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component A.

[0123] Preparation of component B: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 0.2 parts of powder treatment agent H1 to a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 80 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 120 parts of thermal conductive filler and 0.2 parts of pigment, stir for 10 minutes, and scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%) and 0.1 parts of catalyst, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component B.

[0124] Example 5

[0125] Preparation of component A: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 1 part of powder treatment agent H1 into a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 120 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 80 parts of thermal conductive filler and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%), 15 parts of end hydrogen-containing silicone oil (hydrogen content 0.1%), 1.3 parts of side hydrogen-containing silicone oil (hydrogen content 0.36%), and 0.02 parts of inhibitor, and stir in a vacuum for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component A.

[0126] Preparation of component B: (1) Add 20 parts of 300mPa·S-terminated vinyl silicone oil (vinyl content 0.55%) and 1 part of powder treatment agent H1 to a double planetary mixer and stir for 2 minutes; (2) Heat to 100°C, add 120 parts of thermal conductive filler and stir for 10 minutes; (3) Add the remaining 80 parts of thermal conductive filler and 0.5 parts of pigment and stir for 10 minutes, then scrape the edges; (4) Heat to 150°C, vacuum and stir for 60 minutes; (5) After cooling to room temperature, add 20 parts of 100mPa·S-terminated vinyl silicone oil (vinyl content 1%) and 0.1 parts of catalyst, maintain vacuum and stir for 30 minutes; (6) Vacuum and stir for 15 minutes to obtain component B.

[0127] The comparative example is consistent with Example 1 except that the powder treatment agent used is different from that used in Example 1. The powder treatment agents used in the comparative example and each example are shown in Table 1.

[0128] Table 1 Treatment agents used in various examples and comparative examples

[0129] project Treatment agent Example 1 H1 Example 2 H2 Example 3 H3 Example 4 H1 Example 5 H1 Comparative Example 1 Vinyltrimethoxysilane Comparative Example 2 Dodecyltrimethoxysilane Comparative Example 3 Hexadecyltrimethoxysilane Comparative Example 4 /

[0130] 4. Examples and Comparative Examples Performance Test Methods:

[0131] The components A and B in each embodiment and comparative example were used in a mass ratio of 1:1.

[0132] (1) Hardness: Test the hardness of the glue after curing according to GB / T 531.1-2008.

[0133] (2) Viscosity: The viscosity of components A and B in each embodiment and comparative example and after mixing were tested according to GB / T 2794-2013.

[0134] (3) Thermal conductivity: The thermal conductivity of the samples prepared in the examples and comparative examples was tested using a Taiwan Ruiling LW-9389 interface material thermal resistance and thermal conductivity measuring instrument according to ASTM D5470.

[0135] (4) Tensile strength: tested according to GB / T 528-2009.

[0136] (5) Elongation at break: tested according to GB / T 528-2009.

[0137] (6) Linear expansion coefficient: The test was performed using a TMA thermomechanical analyzer (model Q400) from TA Instruments, USA, in accordance with ASTM E831-19.

[0138] (7) Evaluation of heat aging resistance: The silicone potting compound was poured into the aluminum shell where the photovoltaic inverter inductor was placed, vacuumed and cured at 25°C for 24 hours, and then placed in an oven at 150°C for 1000 hours and -

[0139] After 1000 cycles in a 40-125℃ high and low temperature shock box, observe whether there is any cracking between the silicone rubber and the aluminum shell where the inductor is placed. If there is cracking, it is indicated by ×, and if there is no cracking, it is indicated by ○.

[0140] Table 2 Comparison of potting properties between the embodiment and the comparative example

[0141]

[0142]

[0143] From Table 2 we can see that:

[0144] 1. Comparative Example 4 does not use a powder treatment agent to prepare glue. The glue viscosity is too high, which is not conducive to practical application, and the strength of the glue after curing is low. Comparative Example 1 uses vinyltrimethoxysilane as a powder treatment agent. Vinyltrimethoxysilane contains three methoxy groups and one vinyl group in its structure. The powder treatment agent dodecyltrimethoxysilane used in Comparative Example 2 and the powder treatment agent hexadecyltrimethoxysilane used in Comparative Example 3 have increased chain lengths compared to Comparative Example 1. Comparative Examples 1, 2, and 3 use ordinary silane coupling agents to treat the powder, which can effectively reduce the glue viscosity, but has no significant effect on improving the glue strength.

[0145] 2. In Examples 1 to 3, the viscosity of component A and component B is not much different, and the viscosity of component B in each example is lower than 3500 mPa·s. The viscosities of components A and B in Comparative Examples 1, 3, and 4 are all relatively high, while the viscosity of component B in Comparative Example 2 is significantly higher than that of component A. It can be seen from the examples and comparative examples that the use of powder treating agent H can better treat the powder, better reduce the viscosity of the thermal conductive potting compound, and improve the strength and heat resistance of the compound.

[0146] 3. Compared with the existing technology, the present invention uses a treatment agent containing a combination of polyalkoxy, polyvinyl and phenyl groups, wherein the polyalkoxy group can effectively treat the powder to reduce the viscosity; the polyvinyl group can react with the hydrogenated silicone oil in the system under the condition of platinum catalyst, so that the powder and the polymer cross-linked body are tightly combined together, while reducing the linear expansion coefficient of the thermal conductive potting glue, the tensile strength and elongation at break are greatly improved; the introduction of phenyl groups effectively improves the heat resistance of the thermal conductive potting glue. At the same time, the steric hindrance of the phenyl group is relatively large, which further reduces the expansion of the colloid and reduces the linear expansion coefficient. The thermal conductivity of the silicone thermal conductive potting glue prepared by the present invention is greater than 1.5W / (mk), the viscosity is less than 5000mPa·s, the average linear expansion coefficient is less than 120μm / (m·℃), the tensile strength is greater than 3.0MPa, and the elongation at break is greater than 1.5MPa.

[0147] 100%, can effectively solve the problems of poor heat dissipation, expansion cracking, low strength, excessive hardness causing loud noise in power supplies, photovoltaic inverters, reactors, etc. during use.

[0148] Although the present invention has been described herein with reference to illustrative embodiments thereof, it will be understood that those skilled in the art may devise numerous other modifications and implementations that fall within the scope and spirit of the principles disclosed herein. More specifically, within the scope disclosed herein, various variations and improvements may be made to the components and / or layout of the subject combination layout. In addition to variations and improvements made to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A powder treatment agent, characterized in that: Its structural formula is as follows: n is an integer from 1 to 50; Wherein, the structure of R1 is selected from any one of the following structures: a is an integer of 6-20, and b is an integer of 1-3.

2. The powder processing agent according to claim 1, characterized in that It has any of the following structures: In H3, a=12, b=3.

3. The method for preparing the powder treating agent according to claim 1 or 2, characterized in that: The steps include: (1) Stir the end-hydrogenated silicone oil and platinum catalyst evenly; (2) heating to 80°C to 90°C in a nitrogen atmosphere, adding 1,1-bis(trimethoxysilylmethyl)ethylene dropwise, and stirring the reaction for 60 to 90 minutes; (3) cooling and removing unreacted raw materials to obtain auxiliary agent S1; (4) Stirring the additive S2 and platinum catalyst evenly, heating to 80°C to 90°C in a nitrogen atmosphere, adding the additive S1 dropwise, and stirring to react for 60 to 90 minutes; the additive S2 is selected from any one of 1,3,5-trivinylbenzene, triallyl (phenyl) silane, and T-type vinylphenyl silicone oil; (5) cooling and removing unreacted raw materials; (6) Add activated carbon, stir and adsorb, let it stand, and filter to remove the residual platinum catalyst to obtain a powder treatment agent.

4. Use of the powder treatment agent according to claim 1 or 2 in organic silicon thermal conductive potting adhesive.

5. A high-strength, heat-resistant, and crack-resistant silicone thermally conductive potting compound, characterized in that: Made from raw materials including: Component A Component B The powder treatment agent H in component A and component B is the powder treatment agent according to any one of claims 1 to 3.

6. The high-strength, heat-resistant, and crack-resistant organic silicon thermally conductive potting adhesive according to claim 5, characterized in that: The viscosity of the vinyl silicone oil in component A and component B is 100 to 500 mPa·s.

7. The high-strength, heat-resistant, and crack-resistant organic silicon thermally conductive potting adhesive according to claim 5, characterized in that: The thermal conductive fillers in components A and B are compounded from one or more of alumina, silicon micropowder, aluminum hydroxide and magnesium hydroxide with different particle sizes and morphologies, and the powder particle size is 1 to 80 μm.

8. The high-strength, heat-resistant, and crack-resistant organic silicon thermally conductive potting adhesive according to claim 5, characterized in that: The hydrogen-containing silicone oil in component A is compounded from one or more hydrogen-containing silicone oils with a hydrogen content between 0.1% and 0.75%; the inhibitor is compounded from one or more of ethynylcyclohexanol, methylbutynol, and tetramethyltetravinylcyclotetrasiloxane.

9. The high-strength, heat-resistant, and crack-resistant organic silicon thermally conductive potting adhesive according to claim 5, characterized in that: The catalyst in component B is a Custer platinum catalyst; component B contains a pigment, and the pigment is an iron black paste or a carbon black paste.

10. The method for preparing the high-strength, heat-resistant, and crack-resistant organic silicone thermally conductive potting compound according to any one of claims 5 to 9, characterized in that: The following steps are involved: Preparation of component A: (1) Add part of the vinyl silicone oil and all the powder treatment agent H into a double planetary mixer and mix them evenly; (2) Raise the temperature to 100°C, add some thermal conductive filler and stir evenly; (3) Add the remaining thermal conductive filler and stir evenly; (4) Heating to 150°C, vacuuming and stirring; (5) After cooling to room temperature, add the remaining vinyl silicone oil, all hydrogenated silicone oil, and all inhibitors, and stir under vacuum; (6) vacuuming and stirring to obtain component A; Preparation of component B: (1) Add part of the vinyl silicone oil and all the powder treatment agent H into a double planetary mixer and mix them evenly; (2) Raise the temperature to 100°C, add some thermal conductive filler and stir evenly; (3) Add the remaining thermal conductive filler and pigment and stir evenly; (4) Heating to 150°C, vacuuming and stirring; (5) After cooling to room temperature, add the remaining vinyl silicone oil and all the catalysts, and stir under vacuum; (6) Vacuum and stir to obtain component B.

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