Preparation method and use method of bi-component heat-conducting pouring sealant with low dielectric constant

Abstract

The invention provides a preparation method and a use method of a bi-component heat-conducting pouring sealant with a low dielectric constant, and belongs to the technical field of pouring sealant preparation. Vinyl-terminated polydimethylsiloxane, a triethoxy silane coupling agent, spherical aluminum hydroxide, hexagonal boron nitride, side hydrogen-containing silicone oil with the hydrogen content of 0.3%, double-end hydrogen-containing silicone oil with the hydrogen content of 0.1%, a platinum catalyst and iron oxide black are used as raw materials, and a specific treatment process is adopted. The heat-conducting pouring sealant with low dielectric constant and high heat-conducting property is prepared, and the requirements of packaging of electronic components in the fields of high frequency and high power consumption, such as 5G and future 6G communication equipment, server chips, power semiconductors and the like, are met.

Description

Technical Field

[0001] The invention belongs to the technical field of potting glue preparation, in particular to a preparation method and a use method of a two-component low dielectric constant thermal conductive potting glue. Background Art

[0002] With the rapid development of modern information technology, electronic equipment is moving towards high performance, miniaturization and high integration. Especially in the context of the rapid popularization of 5G communication technology, higher requirements are placed on the performance of electronic materials. In 5G communication systems, high-frequency signal transmission requires materials with low dielectric constants to reduce signal attenuation and energy loss. At the same time, the widespread use of high-power components in equipment makes the thermal conductivity of materials an important consideration to ensure that the equipment can quickly dissipate heat and maintain stable operation under high power consumption. Therefore, materials with both high thermal conductivity and low dielectric constant have become the focus of research and development in the field of electronic packaging.

[0003] Thermally conductive potting glue is a widely used packaging material for electronic products. It has good insulation, protection and thermal conductivity. It can pot the internal components and circuits of electronic products and provide moisture-proof, dust-proof and shock-proof protection after curing. However, the common thermally conductive potting glue on the market still has the following performance problems:

[0004] The dielectric constant is generally high: The dielectric constant of existing thermal conductive potting glue is usually between 4 and 8, which is difficult to meet the strict requirements for low dielectric constant in 5G and future 6G high-frequency communications.

[0005] Limited thermal conductivity: The thermal conductivity of common thermally conductive potting compounds on the market is usually between 0.8-1.5W / m·K, which is not enough to fully meet the heat dissipation requirements of high-power components.

[0006] Therefore, how to prepare a thermally conductive potting compound that has both a low dielectric constant and high thermal conductivity is a technical difficulty in the current field of electronic materials. Summary of the invention

[0007] The purpose of the present invention is to solve the above problems in the prior art and to provide a preparation method and a use method of a two-component low dielectric constant thermally conductive potting glue.

[0008] The purpose of the present invention can be achieved by the following technical scheme: a method for preparing a two-component low dielectric constant thermal conductive potting glue, the two-component low dielectric constant thermal conductive potting glue comprises component A and component B, and the method for preparing the two-component low dielectric constant thermal conductive potting glue comprises the following steps:

[0009] S1: preparing an intermediate formula material: after uniformly mixing the vinyl-terminated polydimethylsiloxane and the triethoxysilane coupling agent, adding a thermal conductive filler to obtain a pre-treated mixture, and subjecting the pre-treated mixture to a first stirring operation, a first vacuum stirring operation, a first vacuum high-speed dispersion operation, a second vacuum stirring operation, and a second vacuum high-speed dispersion operation in sequence by a specific process; after the second vacuum high-speed dispersion operation is completed, an intermediate formula material is obtained.

[0010] According to the weight ratio, the vinyl-terminated polydimethylsiloxane: triethoxysilane coupling agent: thermal conductive filler is 50-52: 1-1.1: 150-155; the viscosity of the vinyl-terminated polydimethylsiloxane is 90-110cps,

[0011] The thermal conductive filler includes spherical aluminum hydroxide with a particle size of 50um, spherical aluminum hydroxide with a particle size of 10um, spherical aluminum hydroxide with a particle size of 1um, and hexagonal boron nitride with a particle size of 6-8um. According to the weight ratio, the spherical aluminum hydroxide with a particle size of 50um: the spherical aluminum hydroxide with a particle size of 10um: the spherical aluminum hydroxide with a particle size of 1um: the hexagonal boron nitride is 10-11:4-4.5:1-1.1:18-20;

[0012] In the first stirring operation, the parameters are set as follows: the stirring speed is 20-22rpm, and the stirring temperature is 80-82°C; in the first vacuum stirring operation, the parameters are set as follows: the stirring speed is 25-27rpm, the stirring temperature is 118-122°C, and the vacuum degree is not higher than 0.09MPa; in the first vacuum high-speed dispersion operation, the parameters are set as follows: the stirring speed is 700-750rpm, the stirring temperature is 118-122°C, and the vacuum degree is not higher than 0.09MPa; in the second vacuum stirring operation, the parameters are set as follows: the stirring speed is 30-32rpm, the stirring temperature is 150-155°C, and the vacuum degree is not higher than 0.09MPa; in the second vacuum high-speed dispersion operation, the parameters are set as follows: the stirring speed is 1000-1050rpm, the stirring temperature is 150-155°C, and the vacuum degree is not higher than 0.09MPa;

[0013] S2 prepares component A: take a certain amount of intermediate formula material, add platinum catalyst and colorant to the taken intermediate formula material to obtain component A mixture, and sequentially perform the first high-speed dispersion operation, the second high-speed dispersion operation, the third high-speed dispersion operation and the fourth high-speed dispersion operation on the component A mixture by using specific process 2, and after the fourth high-speed dispersion operation, component A is obtained, and the colorant is specifically black iron oxide; according to the weight ratio, the intermediate formula material: platinum catalyst: black iron oxide is 1000-1010:0.5-0.53:5-5.2;

[0014] In the first high-speed dispersion operation, the stirring speed is 500-550rpm; in the second high-speed dispersion operation, the stirring speed is 700-750rpm, in the third high-speed dispersion operation, the stirring speed is 1050-1100rpm, and in the fourth high-speed dispersion operation, the stirring speed is 1150-1200rpm;

[0015] S3 prepares component B: taking the same weight of the intermediate formula material as that in step S2, adding a crosslinking agent and an inhibitor to the taken intermediate formula material to obtain a component B mixture, and subjecting the component B mixture to a first high-speed dispersion operation, a second high-speed dispersion operation and a third high-speed dispersion operation in sequence by using a specific process three, and after the third high-speed dispersion operation is completed, component B is obtained, and according to the weight ratio, the intermediate formula material: crosslinking agent: inhibitor is 1000-1010:10-10.1:0.1-0.102;

[0016] The crosslinking agent includes a side hydrogen-containing silicone oil with a hydrogen content of 0.3% and a double-end hydrogen-containing silicone oil with a hydrogen content of 0.1%. According to the weight ratio, the side hydrogen-containing silicone oil with a hydrogen content of 0.3% and the double-end hydrogen-containing silicone oil with a hydrogen content of 0.1% are 1:1;

[0017] The inhibitor is acetylene cyclohexanol;

[0018] Vinyl-terminated polydimethylsiloxane: Properties and functions: Vinyl-terminated polydimethylsiloxane is a type of vinyl silicone oil. Its molecular structure contains a polydimethylsiloxane main chain with vinyl (-CH=CH2) groups at both ends. The vinyl group is an active group that can cross-link with a cross-linking agent (such as hydrogenated silicone oil) through a silylation reaction to form a three-dimensional network structure. Its main chain polydimethylsiloxane structure provides good flexibility, low surface tension, high and low temperature resistance and electrical insulation properties. Reasons for selection: High reactivity of the vinyl-terminated group: Under the action of a platinum catalyst, it can quickly react with a cross-linking agent to form a cross-linked solid structure, ensuring the strength, durability and thermal conductivity of the cured adhesive. Distribution characteristics of the vinyl groups at the chain ends: The vinyl groups are mainly concentrated at the ends of the molecular chains, which is conducive to forming a uniform cross-linked network and improving the overall curing performance and toughness. Low dielectric and weather resistance of the main structure: The polydimethylsiloxane main chain itself has excellent low dielectric constant and chemical stability, making it suitable for use as a potting material to ensure product performance.

[0019] The role of triethoxysilane coupling agent: 1. Improve interface bonding: triethoxysilane coupling agent can enhance the compatibility of thermal conductive fillers (aluminum hydroxide and hexagonal boron nitride) and silicone matrix (terminated vinyl polydimethylsiloxane), reduce the mutual repulsion phenomenon at the interface; by forming a stable interface chemical bond, improve the uniformity and mechanical properties of the potting compound. 2. Improve the dispersibility of the system: triethoxysilane coupling agent plays the role of a dispersant on the surface of the filler to avoid the agglomeration of the filler in the matrix. Improve the uniformity of the distribution of the filler in the silicone matrix, thereby improving the thermal conductivity and processing performance of the system. 3. Optimize thermal conductivity: The uniform distribution of thermal conductive fillers in the matrix has a significant effect on the thermal conductivity: through the interface modification of triethoxysilane coupling agent, the thermal conductive filler is more closely bonded to the matrix; reduce the interfacial thermal resistance between the filler and the matrix, and improve the overall thermal conductivity of the potting compound. 4. Improve the low dielectric properties of the material: The coupling agent can reduce the porosity and micro defects in the system by reducing the agglomeration of the filler in the system, which is very important for maintaining the low dielectric constant characteristics. At the same time, its coupling effect helps to reduce dielectric loss and further ensure that the system has a low dielectric constant. 5. Improve the mechanical properties of the material: Triethoxysilane coupling agent can significantly improve the mechanical strength of the potting compound, such as tensile and tear resistance, through the formation of chemical bonds and the improvement of dispersibility. Especially under the condition of high thermal conductivity filler and high load (such as 150-155 weight ratio), the presence of coupling agent can prevent the embrittlement of the material. 6. Reduce the viscosity of the system and optimize the processing performance: In the preparation of potting compound: coupling agent can significantly reduce the viscosity of the entire system by improving the interfacial wettability of the filler; this not only improves the efficiency of the mixing process (such as stirring, high-speed dispersion operation, etc.), but also improves the mixing uniformity of component A and component B, thereby optimizing the preparation and processing performance. Triethoxysilane coupling agent plays an important role in interface regulation in the preparation process of the two-component low dielectric constant thermal conductive potting compound. Its main functions include: interface bonding enhancement: improving the compatibility between the silicone matrix and the inorganic filler; dispersibility improvement: preventing filler agglomeration and improving the uniformity of filler dispersion; thermal conductivity optimization: reducing interface thermal resistance and improving thermal conductivity; low dielectric property maintenance: reducing porosity and dielectric loss; mechanical property improvement: improving the strength and toughness of the potting compound; processing performance improvement: reducing viscosity and optimizing the mixing process. These functions together ensure that the prepared thermal conductive potting compound has excellent comprehensive performance.

[0020] Reasons for selecting thermally conductive fillers and their particle size and weight ratio: Aluminum hydroxide has low cost and good electrical insulation properties. Its thermal conductivity is generally between 0.3-1W / m·K. By optimizing the particle size and dispersibility, its thermal conductivity can be significantly improved. The high expansion coefficient and low density of aluminum hydroxide are suitable for applications in long-term high temperature environments. The thermal conductivity of hexagonal boron nitride is particularly excellent, reaching 100-200W / m·K, which is much higher than many traditional thermal conductive materials. Hexagonal boron nitride provides very high thermal conductivity in thermal conductive adhesives, and its excellent electrical insulation makes it an ideal choice for electronic packaging materials. Its morphology can provide an efficient heat conduction path, especially the flake or layered hexagonal boron nitride has advantages in the direction of thermal conduction, matching thermal expansion coefficient: the thermal expansion coefficient of boron nitride is close to that of aluminum hydroxide, which helps to reduce stress during temperature changes and avoid packaging cracking caused by thermal stress. The hardness of boron nitride and the particle size adaptation of aluminum hydroxide can effectively improve the compressive strength and mechanical stress resistance of the colloid, enhance the stability and shock resistance of the overall package, and ensure reliability in long-term use. Characteristics of spherical aluminum hydroxide: Good dispersibility: The spherical particle shape has a smaller specific surface area, which is conducive to dispersion in the matrix and reduces agglomeration. Enhanced mechanical properties: Its moderate hardness can improve the mechanical strength of the material. Characteristics of hexagonal boron nitride: Low dielectric constant: Hexagonal boron nitride itself has the characteristics of low dielectric constant. While improving thermal conductivity, it will not significantly increase the dielectric constant of the material, making the material suitable for the field of electrical insulation. Lubricity: The layered structure of boron nitride helps to improve processability and reduce frictional resistance generated during the mixing process. Combination of fillers with different particle sizes:

[0021] The selection and matching of particle size have a significant impact on thermal conductivity for the following reasons: Large particle size filler (50μm spherical aluminum hydroxide): Skeleton effect: Larger particles can act as a "skeleton" in the filler network, forming a longer thermal conduction channel, reducing thermal resistance and improving overall thermal conductivity. Reduce interfaces: Larger particles reduce the number of interfaces between the filler and the matrix, thereby reducing interfacial thermal resistance. Medium particle size filler (10μm spherical aluminum hydroxide): Filling gaps: Medium particle size fillers are used to fill the gaps between large particle size fillers, thereby increasing the filler packing density. Enhance thermal conductivity path: Large particle size fillers are connected through medium particle size fillers to form a more complete thermal conductivity path. Small particle size filler (1μm spherical aluminum hydroxide): Further fill gaps: Small particle size fillers can further fill the tiny gaps between large and medium particles, increasing the filler density. Reduce matrix resistance: Because the gaps between the fillers are filled, the heat transfer resistance in the matrix is ​​reduced. Hexagonal Boron Nitride (6-8μm): Supplement thermal conductivity: The layered structure of boron nitride forms a synergistic effect with aluminum hydroxide to provide higher thermal conductivity. Dielectric performance optimization: The addition of boron nitride further reduces the dielectric constant of the system, making it suitable for low dielectric constant applications. Optimization of weight ratio: The weight ratio design of different particle sizes and different fillers is intended to optimize the packing density and thermal conductivity of the filler, while controlling the rheological properties and processing performance. Spherical aluminum hydroxide with a particle size of 50μm (10-11 parts): The higher ratio is because it provides the main thermal conductivity path and plays a skeleton support role. Spherical aluminum hydroxide with a particle size of 10μm (4-4.5 parts): As a filler with an intermediate particle size, it is used to increase the filling density and optimize the thermal conductivity path. Spherical aluminum hydroxide with a particle size of 1μm (1-1.1 parts): Fill tiny gaps with particles to improve thermal conductivity and uniformity of the system. Hexagonal Boron Nitride (18-20 parts): Hexagonal Boron Nitride has a larger proportion because it contributes significantly to the overall thermal conductivity and dielectric properties. At the same time, due to its medium particle size (6-8μm), it can also work with aluminum hydroxide to fill the gaps and improve the thermal conductivity of the system. Combination effect and advantages: Maximized filling efficiency: The reasonable combination of large, medium and small particle size fillers maximizes the packing density of the filler in the matrix, thereby reducing the thermal resistance of the matrix part and improving the overall thermal conductivity. Optimization of thermal conductivity path: Large particle size provides the skeleton, medium particle size connects the thermal conductivity path, and small particle size further reduces the heat transfer resistance in the matrix, realizing a multi-scale synergistic thermal conductivity path. Optimization of rheological properties and processability: The morphology of spherical aluminum hydroxide and hexagonal boron nitride makes the mixture have good fluidity and processability, which is suitable for potting applications. Low dielectric constant performance: The addition of boron nitride significantly reduces the dielectric constant of the system, ensuring the electrical insulation performance of the potting compound in thermal conductivity applications, especially suitable for electronic devices and high-frequency applications.

[0022] Selecting the above thermal conductive fillers and designing a reasonable particle size distribution and weight ratio can provide excellent thermal conductive potting glue based on improving thermal conductivity, reducing dielectric constant, optimizing rheological properties and processability. This material is particularly suitable for scenarios requiring high thermal conductivity and low dielectric constant, such as heat dissipation and insulation applications of electronic devices.

[0023] In order to obtain the best effect, by adding a coupling agent as a surface modifier, the surface modification can significantly improve the dispersion of the thermal conductive filler colloid and avoid the performance degradation caused by particle agglomeration. The selection and matching of the above thermal conductive fillers comprehensively consider the balance between cost and performance, which is specifically reflected in: particle size complementarity: reasonable matching of large, medium and small particle sizes, optimizing filler stacking, reducing voids and improving thermal conductivity; material complementarity: aluminum hydroxide and hexagonal boron nitride provide low-cost advantages and high thermal conductivity and low dielectric properties respectively, forming a synergistic effect; processability optimization: the synergistic effect of particle size matching and material properties improves the viscosity, dispersibility and processing performance of the system; this filler matching strategy not only achieves the goals of low dielectric constant and high thermal conductivity, but also takes into account processability and economy.

[0024] The purpose of using specific process 1 to process the intermediate formula material is to ensure the performance and quality of the two-component low dielectric constant thermal conductive potting glue, while taking into account its production feasibility and cost control. Specifically, the design of specific process 1 reflects the comprehensive consideration of material dispersion, uniformity, viscosity control and thermal conductivity optimization. The following is a detailed analysis from the aspects of the role and advantages of process design, material property requirements, and cost control. The first stirring operation: Goal: Preliminary mixing of the main components (terminated vinyl polydimethylsiloxane, triethoxysilane coupling agent) and thermal conductive fillers to make them evenly distributed. Parameter design: Stirring speed (20-22rpm): A lower stirring speed helps with preliminary mixing to avoid filler agglomeration or material splashing due to too fast stirring. Stirring temperature (80-82℃): A lower temperature can reduce the initial viscosity of the material, improve fluidity, and facilitate the uniformity of preliminary mixing. Function: Disperse the filler evenly in the matrix to form a preliminary mixed state. Provide a uniform material basis for subsequent high-speed dispersion and vacuum processing. The first vacuum stirring operation: Goal: Further enhance the uniformity of the material, and remove the gas in the gaps between large particles through the vacuum environment. Parameter design: Stirring speed (25-27rpm): Slightly higher than the first stirring speed, to enhance the further dispersion effect of the filler. Temperature (118-122℃): Higher temperature reduces the viscosity of the matrix and improves the dispersion efficiency of the filler. Vacuum degree (≤0.09MPa): Operating under a vacuum environment can effectively remove bubbles in the gaps between the fillers and the mixed system, and reduce the porosity after subsequent curing. Function: Improve the compactness of the system and reduce the interfacial thermal resistance between the thermally conductive filler and the matrix. Improve the continuity of the thermal conductivity path and optimize the final thermal conductivity. The first vacuum high-speed dispersion operation: Goal: Efficiently disperse the material under a vacuum environment to ensure that the filler particles are evenly distributed and fully wetted. Parameter design: Stirring speed (700-750rpm): High-speed dispersion can completely break up the agglomeration of the filler and form a more uniform dispersion system. Temperature (118-122℃): Maintain a high temperature to make the system viscosity moderate, which is conducive to high-speed dispersion. Vacuum degree (≤0.09MPa): further eliminate possible residual bubbles to ensure the density of the material. Function: Improve the uniform dispersion of the filler to avoid the decrease in thermal conductivity or inconsistent material performance due to particle agglomeration. Optimize the bonding between the filler and the matrix interface to further reduce the interfacial thermal resistance. Second vacuum stirring operation: Goal: Slowly homogenize the material after high-speed dispersion to eliminate possible local concentration unevenness. Parameter design: Stirring speed (30-32rpm): Reduce the speed again to allow the system to enter the homogenization stage. Temperature (150-155℃): The material has better fluidity at higher temperatures, further reducing microscopic unevenness. Vacuum degree (≤0.09MPa): Maintain a vacuum environment to ensure that no new bubbles are introduced during the stirring process. Function: Blend the system after high-speed dispersion to make the filler particles more evenly distributed.Lay the foundation for the final high-speed dispersion operation. The second vacuum high-speed dispersion operation: Goal: To perform the final high-speed dispersion of the system to ensure the uniform distribution of the filler, the dense accumulation of the particles and the complete degassing of the system. Parameter design: Stirring speed (1000-1050rpm): The highest dispersion speed ensures that the filler in the system is thoroughly dispersed. Temperature (150-155℃): Under high temperature environment, the filler and the matrix are more closely combined, and the viscosity is further reduced. Vacuum degree (≤0.09MPa): Continuously eliminate tiny bubbles during high-speed dispersion to ensure the density of the system. Function: Improve the dispersion and uniformity of the filler in the matrix to ensure the final performance of the system. Further reduce the interfacial thermal resistance and microporosity, and improve thermal conductivity and mechanical properties.

[0025] The necessity of adopting a specific process in terms of cost control is as follows: Multi-stage dispersion prevents filler waste: During multiple high-speed dispersion processes (especially in a vacuum environment), filler agglomeration is fully broken up and particles are evenly distributed. This prevents fillers from settling in the matrix due to poor dispersion or forming "ineffective filler" areas that do not participate in conduction, thereby maximizing the thermal conductivity of the filler.

[0026] It achieves efficient use of fillers, reduces the amount of fillers required, and reduces raw material costs while improving thermal conductivity. Gradually increasing stirring process: The process sets up a step-by-step operation from low speed to high speed (such as 20rpm→25rpm→700rpm→1050rpm). This design avoids excessive equipment load or energy waste caused by direct high-speed stirring. The initial stirring stage reduces the viscosity before high-speed dispersion, which significantly reduces the energy consumption in the high-speed stage. Staged temperature control energy saving:

[0027] The gradual increase in temperature (from 80°C to 155°C) matches the stirring requirements of each stage, which not only reduces unnecessary heat energy consumption, but also optimizes the dispersion efficiency of the filler. The high temperature reduces the viscosity of the material, shortens the high-speed dispersion time, and further reduces energy consumption. Reduce equipment wear and maintenance costs: Reasonable speed control and vacuum operation avoid the wear of equipment components (such as stirring blades) caused by filler agglomeration during high-speed stirring, extend the service life of the equipment, and reduce long-term maintenance costs. Reduce manual intervention: The process is highly standardized, so that the production process can be automated, reducing the cost and error rate of manual operation.

[0028] Necessity analysis of specific process 1: The performance of thermally conductive potting glue is closely related to the dispersion state of thermally conductive fillers, and thermally conductive fillers have the following challenges: Filler agglomeration phenomenon: Thermally conductive fillers (such as aluminum hydroxide and hexagonal boron nitride) are prone to agglomeration during mixing, which affects the dispersion effect and causes discontinuous thermal conductivity paths in the system. Through multiple high-speed dispersion operations, the agglomeration phenomenon can be gradually broken and the uniformity of the particles can be improved. Wettability of fillers and substrates: Vacuum environment and high-temperature operation can enhance the wetting effect of fillers and improve the bonding between particles and substrates. System bubble residue problem: Residual bubbles in potting glue materials will greatly reduce thermal conductivity and mechanical strength. Vacuum treatment effectively removes bubbles during the mixing process to ensure the density of the material. The need for particle size gradient optimization: The reasonable stacking of fillers of different particle sizes is the key to optimizing thermal conductivity. Multi-stage stirring and dispersion processes can ensure uniform distribution of fillers of different particle sizes and avoid particle stratification and sedimentation.

[0029] Contribution of specific process 1 to the final performance: Thermal conductivity: Through multiple vacuum high-speed dispersion and stirring operations, the filler particles are evenly distributed and tightly packed to form a continuous thermal conductivity path, which greatly improves the thermal conductivity. Low dielectric constant: The optimized filler distribution reduces the voids and micropores inside the material, ensuring the low dielectric constant characteristics of the system. Processability and fluidity:

[0030] The multi-stage process reduces the viscosity of the system through high temperature, improves the fluidity of the material, and facilitates subsequent processing and use. Mechanical properties: Highly dispersed fillers and dense stacking effectively improve the mechanical strength and toughness of the material.

[0031] The specific process 1 is used to process the intermediate formula material in order to meet the comprehensive requirements of the two-component low dielectric constant thermal conductive potting adhesive in terms of thermal conductivity, dielectric properties, mechanical properties and processability. Through the reasonable design of process parameters, the problems of agglomeration, poor wettability and residual bubbles in the filler system are overcome, ensuring the high performance of the material and the stability of production, while taking into account cost control on the basis of performance improvement.

[0032] The purpose of using specific process 2 for processing is to further optimize the performance of component A, so that it can achieve efficient catalysis and performance stability in the two-component low dielectric constant thermal conductive potting glue, while controlling production costs and improving material quality. The necessity and advantages of using specific process 2 for processing are analyzed from the following perspectives: Improving the dispersion uniformity of the catalyst and the base material: The dispersion of the platinum catalyst and the intermediate formula directly affects the uniformity and efficiency of the reaction, and the multiple high-speed dispersion operations in specific process 2 are an important guarantee for improving the dispersion uniformity: Multi-stage dispersion ensures uniform distribution of the catalyst:

[0033] During the preparation of component A, the amount of platinum catalyst used is very small (0.5-0.53). If it is not dispersed evenly, the local catalytic efficiency may be too high or too low, resulting in incomplete reaction or local failure. By gradually increasing the stirring speed (from 500rpm to 1200rpm), specific process 2 can make the catalyst particles fully and evenly distributed in the matrix, avoiding the problems of uneven catalysis, low efficiency or high scrap rate caused by poor dispersion. High dispersion performance ensures the maximum effect of trace components: Platinum catalyst is a precious metal and its cost is high, so it is necessary to ensure that the amount of catalyst is as small as possible while maximizing the effect. Through multiple high-speed dispersions in specific process 2, the platinum catalyst can fully contact with the intermediate formula material, the catalytic efficiency is significantly improved, and unnecessary waste is reduced. 2. Ensure uniform distribution of colorants and improve the consistency of material appearance:

[0034] The colorant black iron oxide is added to component A to give the material color. Specific process 2 ensures uniform dispersion of the colorant, thereby optimizing the material appearance and market competitiveness: Preventing colorant agglomeration and improving appearance quality: If the colorant is unevenly dispersed in the formula, it may cause color spots or uneven colors, affecting the product appearance and customer acceptance. By gradually increasing the stirring speed, specific process 2 can fully disperse the colorant particles in the base material to ensure the uniformity and consistency of the material color. Color uniformity facilitates quality control: The uniform distribution of colorants can quickly determine whether the material is qualified through visual inspection, which helps to improve the quality control efficiency in the production process and reduce the scrap rate. 3. Prevent local overheating or degradation of the catalyst and base material: In specific process 2, the design of gradually increasing the dispersion speed can avoid the degradation of the catalyst or base material due to local overheating: Gradually increasing the speed to avoid excessive shear force: Direct use of high-speed dispersion is likely to cause the material to overheat due to excessive shear force or friction, which in turn causes local degradation of the platinum catalyst or base material, affecting the material performance. Specific process 2 gradually increases the dispersion speed (500rpm→1200rpm) to make the dispersion process more gentle and ensure that the material is in a stable physical and chemical state. Improve the fluidity and stability of the mixed system: Through multiple dispersion treatments in specific process 2, the fluidity and stability of component A have been significantly improved: Reduce viscosity and improve the convenience of subsequent operations: The shear force generated during the high-speed dispersion process helps to reduce the viscosity of the mixture, making it easier for subsequent storage, transportation and mixing operations. The reduction in the viscosity of component A can also ensure the fluidity and mixing uniformity when mixed with component B, thereby improving the quality of the end product. Prevent stratification and sedimentation: If the platinum catalyst or colorant is not completely dispersed, it may cause the mixture to settle or stratify during storage, affecting the long-term stability of the material. After being treated in specific process 2, component A with good dispersion is more stable and is not prone to stratification or sedimentation. Avoid the influence of bubbles, and eliminate bubbles by shear force and speed control: The gradual increase in the dispersion speed can gradually eliminate the mixed bubbles during the dispersion process, avoiding the phenomenon of a large number of bubbles directly generated by high-speed dispersion. This control method reduces the bubble content in component A and improves the density and thermal conductivity of the material. Improve the dielectric properties of the end product: Residual bubbles will increase the dielectric constant of the material, affecting the low dielectric properties of the potting compound. The bubble control measures in the dispersion process of Specific Process 2 ensure that the low dielectric properties of component A meet the design requirements. Multiple high-speed dispersions ensure the repeatability and standardization of the process: The dispersion steps of Specific Process 2 are scientifically designed to ensure the standardization and repeatability of the process, which is convenient for large-scale production: Clear parameters and easy to replicate: The dispersion speed (500rpm→1200rpm) and operation sequence (4 high-speed dispersions) are precisely designed so that the process can be consistent in different batches, reducing the variables caused by manual intervention.The highly standardized process improves production efficiency and reduces the defective product rate caused by human factors. Adapt to automated production: The process settings are simple and clear, suitable for combination with automated equipment, reducing manual operation costs and improving production efficiency.

[0035] The specific process 2 is used to treat component A in order to achieve the best results in terms of uniformity of platinum catalyst dispersion, uniformity of colorant, stability of the mixture and quality control. At the same time, by gradually increasing the dispersion speed, the problems of local overheating and residual bubbles are avoided, thus ensuring the performance stability of component A and the high quality of the terminal material. This process design not only improves product performance, but also takes into account the requirements of cost control and large-scale production, creating greater economic benefits for the company.

[0036] The purpose of using specific process 3 for treatment is to optimize the performance of component B so that it can better match component A, thereby achieving ideal cross-linking reaction efficiency, good thermal conductivity and stable low dielectric constant in the two-component low dielectric constant thermal conductive potting glue, while taking into account the controllability of the production process and cost optimization. The following is a detailed analysis of the necessity and advantages of using specific process 3 from the perspective of process requirements and material properties: Ensure the uniform dispersion of the cross-linking agent and the base material to improve the cross-linking efficiency: The importance of cross-linking agent dispersion uniformity: The cross-linking agent (side hydrogen silicone oil and double-end hydrogen silicone oil) in component B is the key component that determines the efficiency of the cross-linking reaction of the potting glue. Specific process 3 ensures that the cross-linking agent can be evenly distributed in the intermediate formula by gradually increasing the stirring speed (from 600rpm to 950rpm), avoiding local concentrations that are too high or too low, and preventing uneven cross-linking reactions or reduced efficiency. Characteristics of the cross-linking agent: The two cross-linking agents (side hydrogen silicone oil and double-end hydrogen silicone oil) have different hydrogen contents (0.3% and 0.1%), and need to be accurately proportioned and fully dispersed to achieve synergistic effects. If the dispersion is uneven, it may cause problems such as uneven hardening and insufficient crosslinking of the potting glue during use, thereby affecting the mechanical properties and thermal conductivity of the material. Prevent uneven distribution of the inhibitor and ensure the controllability of the crosslinking reaction: Inhibitor function: The inhibitor acetylene cyclohexanol functions to delay the occurrence of the crosslinking reaction so that there is enough operating time after the A and B components are mixed. The amount of the inhibitor used is very small (0.1-0.102), and its distribution uniformity is directly related to the control accuracy of the crosslinking reaction. The necessity of multi-stage high-speed dispersion: Since the inhibitor is difficult to disperse, if only a single high-speed dispersion process is used, it may cause uneven distribution in the base material, which in turn causes the problem of local reaction being too fast or too slow. Specific process 3 uses a high-speed dispersion process with three step-by-step speed increase (600rpm→950rpm) to ensure that the inhibitor can be evenly dispersed in the entire system, thereby achieving controllability and consistency of the reaction. Improve the mixing uniformity and stability of materials: The importance of multi-stage dispersion: The density and particle properties of the intermediate formula and additives (crosslinking agent, inhibitor) are different, and it is easy to produce stratification or unevenness due to insufficient dispersion.

[0037] Specific process 3 uses three high-speed dispersion treatments to make the mixing of materials more uniform, eliminating the sedimentation or stratification problems that may be caused by poor dispersion. Improve material stability: Component B after uniform dispersion is more stable and is not easy to separate during storage, thus ensuring the performance and shelf life of the product. Avoid local overheating and protect the chemical activity of additives: Advantages of the gradual speed increase design: During the dispersion process, excessive stirring speed is prone to generate a large amount of shear heat, which leads to a decrease in the activity of the crosslinker or inhibitor. Specific process 3 can fully disperse the materials and avoid the failure of chemical components due to local overheating by gradually increasing the stirring speed (from 600rpm to 950rpm). Ensure the activity of chemical components: The chemical properties of hydrogenated silicone oil are relatively active and sensitive to temperature and stirring conditions. The gradually increasing speed dispersion process avoids the problem of side reactions or reduced activity due to local overheating, thereby ensuring the functional effect of the crosslinker. Improve the processing fluidity and operability of component B: Reduce the viscosity of the mixture and improve fluidity: Specific process 3 can effectively reduce the viscosity of component B through high-speed dispersion, making it easier to operate during subsequent storage, transportation and mixing with component A. Good fluidity helps components A and B to be quickly and evenly distributed after mixing, thereby ensuring the performance consistency of the two-component material. Reduce bubble formation and improve product quality: During the dispersion process, the formation of bubbles may lead to an increase in the dielectric constant of the material and a decrease in thermal conductivity. Specific process 3 avoids the bubble problem caused by high-speed dispersion by optimizing the dispersion speed and time, thereby improving the quality of component B. Ensure the stability and repeatability of the production process: Clear parameters and easy process control: The dispersion speed and sequence of specific process 3 are precisely designed to ensure that the process can remain consistent in different batches, reducing product fluctuations caused by manual intervention. The standardized process flow is easy to promote and apply in large-scale production, improving production efficiency and product consistency. Adapt to the needs of automated production: The dispersion steps and parameter settings of specific process 3 are simple and clear, which can be well adapted to automated equipment and further reduce production costs. Improve the electrical and thermal conductivity of terminal materials: Achieve low dielectric constant: By precisely dispersing the cross-linker and inhibitor, component B can be evenly cross-linked with component A during mixing, and the final solidified body is denser, reducing internal voids and residual bubbles, thereby reducing the dielectric constant of the material. Optimize thermal conductivity: Evenly dispersed cross-linkers can enable thermally conductive fillers to form a better thermal conductivity path in the solidified body, improve thermal conductivity efficiency, and ensure that the thermal conductivity of the potting compound meets the design requirements. The specific process 3 is used to treat component B in order to achieve uniform dispersion of the cross-linker and inhibitor, ensure the controllability and efficiency of the cross-linking reaction, and optimize the stability, fluidity and processing performance of component B. By gradually increasing the dispersion speed, it is possible to avoid local overheating problems and reduce bubble formation, thereby ensuring that component B performs stably and reliably in the final potting compound.In addition, specific process 3 also lays the foundation for the standardization and large-scale production of the process, providing important support for enterprises to reduce costs and improve efficiency.

[0038] The use of side hydrogen-containing silicone oil with a hydrogen content of 0.3% and double-terminal hydrogen-containing silicone oil with a hydrogen content of 0.1% as crosslinking agents, and the proportioning according to the weight ratio of 1:1, has many scientific considerations and optimization reasons. This combination design can meet the requirements of two-component low dielectric constant thermal conductive potting glue in terms of chemical reactivity, physical properties, process stability, etc., and the specific analysis is as follows: Optimize the controllability of the crosslinking reaction: The difference between the two hydrogen-containing silicone oils: Side hydrogen-containing silicone oil: Because its side chain contains hydrogen bonds, it is easier to react with the vinyl end of vinyl polydimethylsiloxane, and its reaction rate is relatively fast. Double-terminal hydrogen-containing silicone oil: Its hydrogen bonds are mainly concentrated at both ends of the molecular chain, and the reaction rate is slower, but the depth of the reaction is greater, which helps to form a more uniform and dense crosslinking network. The scientific nature of the 1:1 ratio: Side hydrogen-containing silicone oil provides a fast reaction, which can initially build a crosslinking network in a short time and provide initial strength for the material. The reaction of double-terminal hydrogen-containing silicone oil is slower, which helps the subsequent reaction to improve the network structure and make the overall performance of the material more uniform. By combining two crosslinking agents, it is possible to achieve rapid initial crosslinking while avoiding the problem of shortened operating window caused by too fast reaction (such as decreased fluidity after mixing components A and B). Improve the mechanical properties of the cured body: The role of side hydrogen silicone oil: The reaction of hydrogen silicone oil is more inclined to construct a linear or slightly branched crosslinked structure, which provides a certain flexibility in the initial curing stage, making the cured material less likely to crack under external force. The role of double-ended hydrogen silicone oil: Both ends of the double-ended hydrogen silicone oil participate in the crosslinking reaction, which helps to form a denser three-dimensional crosslinked network and improve the strength and modulus of the cured body. The 1:1 ratio of the two crosslinking agents makes the cured body have both appropriate flexibility (from the side hydrogen silicone oil) and excellent strength and thermal stability (from the double-ended hydrogen silicone oil). Control the low dielectric constant characteristics of the material: The uniformity of the crosslinking network: The synergistic effect of the side hydrogen silicone oil and the double-ended hydrogen silicone oil can form a uniform crosslinking network, reducing the structural defects caused by excessive or low local crosslinking density inside the material. The uniform cross-linking network reduces the uneven distribution of polar groups or charges in the solidified body, reduces the dielectric loss of the material, and thus achieves a stable low dielectric constant. Optimize filler distribution: Under the action of a suitable proportion of cross-linking agent, fillers (such as aluminum hydroxide and hexagonal boron nitride) can be more evenly distributed in the solidified body, reducing the fluctuation of dielectric properties caused by uneven distribution of fillers. Improve thermal conductivity: The key role of double-ended hydrogenated silicone oil: The uniform cross-linking characteristics of double-ended hydrogenated silicone oil help the filler form a continuous thermal conductivity path in the solidified body. The formation of this path is the key to thermal conductivity and can greatly improve the thermal conductivity efficiency of the material. The auxiliary role of side hydrogenated silicone oil: Side hydrogenated silicone oil provides appropriate flexibility to prevent the material from damaging the thermal conductivity path due to excessive shrinkage or stress concentration during the curing process.Synergistic effect of two crosslinking agents: The combination of the rapid crosslinking reaction of the side hydrogenated silicone oil and the deep crosslinking reaction of the double-end hydrogenated silicone oil ensures that the thermally conductive filler and the matrix can maintain a good dispersion and bonding state in both the early and late curing stages, thereby significantly improving the thermal conductivity. Reduce the risk of thermal decomposition: If only the side hydrogenated silicone oil is used, the crosslinking network may not be dense enough, and the material is prone to thermal decomposition under high temperature conditions. Adding double-end hydrogenated silicone oil can effectively avoid this problem and improve the stability of the material during high temperature and long-term use. Meet the production process requirements: Balance between fluidity and operation time: After the A and B components of the two-component potting glue are mixed, a certain amount of operation time is required to complete potting, filling and other operations. The 1:1 ratio design of the side hydrogenated silicone oil and the double-end hydrogenated silicone oil avoids the problem of shortened operation time due to too fast crosslinking reaction, while ensuring the full progress of the crosslinking reaction. Adapt to mass production and automation needs: The 1:1 ratio is simple and easy to control, which is not only convenient for accurate measurement and standardization of production processes, but also reduces product performance fluctuations caused by ratio errors. Economical efficiency of materials: The synergistic effect of side hydrogen-containing silicone oil and double-end hydrogen-containing silicone oil reduces the use of high hydrogen-containing silicone oil, which can not only meet performance requirements but also effectively reduce production costs. Reduce waste and rework risks: At a 1:1 ratio, the reaction is more uniform, the performance of the cured product is stable, and the scrap rate and rework cost caused by uneven cross-linking are reduced.

[0039] The side hydrogen-containing silicone oil with a hydrogen content of 0.3% and the double-end hydrogen-containing silicone oil with a hydrogen content of 0.1% are used in a weight ratio of 1:1. The main purpose is to achieve a balance between rapid initial cross-linking and deep subsequent cross-linking, optimize the efficiency and uniformity of the cross-linking reaction, and thus ensure the low dielectric constant, excellent thermal conductivity, mechanical properties and thermal stability of the material. At the same time, this ratio design facilitates the control and optimization of the production process, can meet the needs of mass production and cost-effectiveness, and is a key technical means in the preparation of two-component low dielectric constant thermal conductive potting glue.

[0040] Reasons for choosing acetylene cyclohexanol as an inhibitor and its dosage: The reason why acetylene cyclohexanol was chosen as an inhibitor is mainly based on its chemical properties, functional requirements, mechanism of action with platinum catalysts and its significant advantages in two-component potting adhesives. The following is a detailed analysis from multiple aspects: Mechanism of action with platinum catalysts: Reversibility of inhibition: The acetylene cyclohexanol molecule contains acetylenic groups (C≡C) and hydroxyl groups (-OH), among which the acetylenic groups can form weak coordination bonds or complexes with the active center of the platinum catalyst, thereby temporarily reducing the activity of the catalyst. This inhibition is reversible. When heated to a higher temperature, acetylene cyclohexanol will release the activity of the platinum catalyst to ensure the smooth completion of the hydrosilylation reaction. High compatibility of the inhibitor with the system: The hydroxyl groups of acetylene cyclohexanol make it more soluble and dispersible in the silicon-based system, and it can work evenly without affecting the performance of other chemical components of the system. Avoid premature reaction, low temperature inhibition, high temperature release: At room temperature or lower temperature, acetylene cyclohexanol stably inhibits the activity of the platinum catalyst and prolongs the operating window time. During the high-temperature curing stage, the inhibitory effect of acetylene cyclohexanol is gradually released, allowing the reaction to be completely cured. Avoid premature curing: Environmentally friendly and safe: Low toxicity and strong environmental protection: The toxicity of acetylene cyclohexanol is much lower than some traditional inhibitors (such as p-benzoquinone or highly volatile acetylene compounds), making it safer and more environmentally friendly. It has low volatility (low VOC emissions) and is not easy to pollute the operating environment. Good decomposition: During the curing process, acetylene cyclohexanol will be completely decomposed into harmless by-products, with no negative impact on the final product and the environment. System compatibility: Acetylene cyclohexanol has good dispersibility in silicone matrix and filler, and will not cause system stratification or precipitation due to compatibility problems. Advantages compared to other inhibitors: Compared with p-benzoquinone: Although p-benzoquinone has a good inhibitory effect, it has high toxicity, poor safety, and insufficient accuracy in temperature control release. Compared with other acetylene compounds: Although other acetylene compounds (such as acetylene or propyne) can inhibit the activity of catalysts, they are highly volatile and unstable, and may be lost during storage or processing, resulting in unstable inhibition. Compared with other acetylene alcohol compounds: acetylene cyclohexanol has larger molecules and higher stability than other acetylene alcohol inhibitors (such as acetylene butanol), and the polarity of the hydroxyl group enhances its solubility and dispersibility in the system. Reasons for the use of acetylene cyclohexanol: Significant effects can be achieved with low dosage: The molecular structure of acetylene cyclohexanol makes its inhibition efficiency high, and only low concentrations are required to produce a significant inhibitory effect on the catalyst activity. Economic considerations: Due to the low dosage and superior performance of acetylene cyclohexanol, it can effectively reduce the overall cost of materials while meeting environmental protection and safety requirements.

[0041] The selection of acetylene cyclohexanol as an inhibitor is based on its comprehensive advantages of high efficiency, stability, safety and environmental protection. It can significantly inhibit the activity of platinum catalysts at low concentrations, ensuring that the two-component potting glue has sufficient working time during the operation phase. The precise control of the dosage reflects its high efficiency and economy, which can not only meet industrial needs but also reduce costs.

[0042] Preferably, in the first high-speed dispersion operation, the stirring speed is 600-650 rpm; in the second high-speed dispersion operation, the stirring speed is 700-750 rpm; in the third high-speed dispersion operation, the stirring speed is 900-950 rpm.

[0043] Preferably, in step S1, in the first stirring operation, first stir for 55-65 minutes, then scrape the sides and bottom, and continue stirring for 55-65 minutes; in the first vacuum stirring operation, the stirring time is 10-15 minutes; in the first vacuum high-speed dispersion operation, the stirring time is 115-125 minutes, in the second vacuum stirring operation, the stirring time is 10-15 minutes; in the second vacuum high-speed dispersion operation, the stirring time is 115-125 minutes.

[0044] Preferably, in step S2, in the first high-speed dispersion operation, the stirring time is 10-12 minutes; in the second high-speed dispersion operation, the stirring time is 10-12 minutes; in the third high-speed dispersion operation, the stirring time is 30-32 minutes; in the fourth high-speed dispersion operation, the stirring time is 30-35 minutes.

[0045] Preferably, in step S3, in the first high-speed dispersion operation, the stirring time is 20-22 minutes; in the second high-speed dispersion operation, the stirring time is 20-25 minutes; in the third high-speed dispersion operation, the stirring time is 30-35 minutes.

[0046] Preferably, in the first stirring operation, the first vacuum stirring operation and the second vacuum stirring operation, a planetary stirring device is used for stirring.

[0047] Preferably, for the first vacuum stirring operation, the first vacuum high-speed dispersion operation, the second vacuum stirring operation and the second vacuum high-speed dispersion operation, the vacuum parameters are set as follows: the vacuum degree is not higher than 0.09 MPa.

[0048] A method for using a two-component low dielectric constant thermal conductive potting glue, wherein the two-component low dielectric constant thermal conductive potting glue is prepared by the above-mentioned preparation method, component A and component B are mixed to obtain a potting glue mixture, the potting glue mixture is sequentially subjected to high-speed dispersion operations and vacuum degassing operations to obtain a target potting glue, the target potting glue is poured into a potting object by a layer-by-layer pouring method, and after the pouring is completed, a curing operation is performed; according to the weight ratio, component A:component B is 1:1.

[0049] Preferably, the specific steps of the high-speed dispersing operation are as follows: using a high-speed disperser, stir the potting glue mixture at a stirring speed of 500-550rpm for 5-7 minutes, and then scrape the edges and bottom. After the operation is completed, keep the stirring speed unchanged and continue stirring for 5-6 minutes.

[0050] Preferably, in the curing operation, the curing temperature is 118-122° C. and the curing time is 60-65 minutes.

[0051] Preferably, the vacuum degassing treatment is performed for 5-7 minutes.

[0052] Compared with the prior art, the preparation method and use method of the two-component low dielectric constant thermal conductive potting glue have the following beneficial effects:

[0053] 1. Realization of low dielectric constant: The present invention adopts a rationally designed formula system, and adopts the synergistic effect of terminal vinyl polydimethylsiloxane and thermal conductive fillers of specific particle size (such as spherical aluminum hydroxide and hexagonal boron nitride of different particle sizes) to significantly reduce the dielectric constant of the prepared thermal conductive potting glue, which can meet the requirements of 5G and future 6G high-frequency communication equipment for low dielectric constant materials, and effectively reduce energy loss and signal attenuation during signal transmission.

[0054] 2. Realization of high thermal conductivity: The present invention forms an efficient thermal conduction channel inside the potting compound by precisely controlling the type and particle size distribution of thermal conductive fillers (such as 50μm, 10μm, 1μm spherical aluminum hydroxide and 6-8μm hexagonal boron nitride), which greatly improves the thermal conductivity of the material. The thermal conductivity coefficient of the prepared thermal conductive potting compound is significantly higher than that of conventional products on the market, and can meet the heat dissipation requirements of high-power components.

[0055] 3. Stable and reliable mechanical properties: By optimizing the addition ratio and process parameters of the coupling agent (triethoxysilane coupling agent), the potting glue prepared by the present invention has excellent mechanical strength and stability after curing, and can effectively protect electronic components from external mechanical stress, vibration and impact, thereby improving the service life and reliability of electronic equipment.

[0056] 4. Excellent process controllability: The present invention ensures uniform distribution of components during mixing, reduces bubble generation, improves fluidity and molding performance of potting compound, and ensures consistency and stability of product performance by finely controlling temperature, rotation speed and vacuum degree in mixing, stirring and high-speed dispersion processes.

[0057] 5. Environmental protection and operability improvement: The inhibitor used in the present invention is acetylene cyclohexanol, which has excellent inhibitory effect, can prolong the operation time, and improve the convenience of use. At the same time, the raw materials used are non-toxic and environmentally friendly, which meets the environmental protection requirements of electronic product packaging materials.

[0058] 6. Wide range of applications: Since the two-component low dielectric constant thermal conductive potting glue of the present invention has high thermal conductivity, low dielectric constant, excellent insulation performance and reliable mechanical properties, it is particularly suitable for the packaging of electronic components in high-frequency and high-power consumption fields such as 5G and future 6G communication equipment, server chips, power semiconductors, etc.

[0059] In summary, the present invention has successfully developed a thermally conductive potting adhesive with both low dielectric constant and high thermal conductivity through scientific formula design and optimized preparation process, which effectively solves the deficiencies in the prior art and has significant technical advantages and broad application prospects. DETAILED DESCRIPTION

[0060] The following are specific embodiments of the present invention, which further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0061] The preparation method of the two-component low dielectric constant thermal conductive potting glue comprises component A and component B. The preparation method of the two-component low dielectric constant thermal conductive potting glue comprises the following contents:

[0062] Raw material preparation: (1) Select end-vinyl polydimethylsiloxane with a viscosity of 100cps; (2) Triethoxysilane coupling agent is used as the treatment agent; (3) Thermal conductive filler: spherical aluminum hydroxide with particle sizes of 50um, 10um and 1um and hexagonal boron nitride with particle size of 7um, the mass ratio is 10:4:1:19 respectively (4) The catalyst is a platinum catalyst with a content of 10000ppm; (5) The colorant is black iron oxide. (6) The cross-linking agent is a side hydrogen-containing silicone oil (hydrogen content of 0.3%) and a double-end hydrogen-containing silicone oil (hydrogen content of 0.1%), the mass ratio is 1:1; (7) The inhibitor is acetylene cyclohexanol;

[0063] Preparation process:

[0064] Preparation of intermediate ingredients: Add 500g of raw material (1) to the cylinder of a 5L dynamic mixer, then add 10g of raw material (2), and stir at 15rpm for 5 minutes. Then add 1500g of raw material (3), stir at 20rpm and 80℃ for 1 hour, and scrape the edges and bottom after completion; continue to stir under the above conditions for 1 hour, and scrape the edges and bottom after completion; then control the temperature at 120℃, start vacuuming, control the vacuum degree to be below 0.09MPa, set the planetary stirring speed to 25rpm, stir for 10 minutes, then use a high-speed dispersion speed device, set the stirring speed to 700rpm, stir for 2 hours, open the air release valve after completion, and then scrape the edges and bottom; then control the temperature at 150℃, control the vacuum degree to be below 0.09MPa, set the planetary stirring speed to 30rpm, and stir for 15 minutes, and finally use a high-speed dispersion speed device, set the stirring speed to 1000rpm, and stir for 2 hours. Cool to room temperature to obtain the intermediate ingredients.

[0065] Preparation of component A: In a 2L jar, add 1kg of the intermediate ingredients prepared above, then add 0.5g of raw material (4) and 5g of raw material (5), and disperse them for 10 minutes using a high-speed dispersing device, with a stirring speed of 500rpm. After the dispersion is completed, scrape the sides and bottom; increase the stirring speed to 700rpm, stir for 10 minutes, and after the dispersion is completed, scrape the sides and bottom; increase the stirring speed to 1100rpm, stir for 30 minutes, and after the dispersion is completed, scrape the sides and bottom; finally increase the stirring speed to 1200rpm, stir for 30 minutes, and after the dispersion is completed, scrape the sides and bottom. Obtain component A.

[0066] Preparation of component B: In a 2L jar, add 1kg of the intermediate ingredient prepared above, then add 10g of raw material (6) and 0.1g of raw material (7), and disperse using a high-speed dispersing device for 20 minutes at a stirring speed of 600rpm. After dispersion, scrape the sides and bottom; increase the stirring speed to 700rpm, stir for 20 minutes, and after dispersion, scrape the sides and bottom; increase the stirring speed to 900rpm, stir for 30 minutes, and after dispersion, scrape the sides and bottom; obtain component B.

[0067] Use and performance test of potting glue:

[0068] Take a 2L jar, add 500g component A and 500g component B in turn, stir at 500rpm for 5 minutes using a high-speed disperser, scrape the sides and bottom after completion, and continue stirring for 5 minutes. Then put it in a vacuum box for 5 minutes to evacuate and degas, then bake it in a 120℃ oven for 1 hour to finally obtain a cured sample. The sample was tested. The thermal conductivity test standard refers to ASTMD5470, and the dielectric constant test standard refers to ASTMD150. The results are as follows: thermal conductivity (W / m·K) is 1.1; dielectric constant is 2.9.

[0069] Thermally conductive potting glue is a material that can be used to pot the internal components and circuits of electronic products. After curing, it can achieve the following main functions: protection function: prevent components from being damaged by environmental factors such as moisture, dust, and mechanical vibration; insulation function: provide electrical insulation to prevent short circuits or leakage; heat dissipation function: effectively dissipate heat through thermal conductive materials to avoid overheating damage; chemical stability: prevent chemical corrosion. In traditional thermally conductive potting glue, the dielectric constant is usually high (4-8), which may cause signal interference and energy loss for electronic products with high-frequency and high-speed signal transmission, especially 5G communication equipment. Therefore, higher requirements are placed on potting glue: high thermal conductivity and low dielectric constant.

[0070] According to the test of the present invention, the main performance indicators of the thermal conductive potting glue are: thermal conductivity: 1.1W / m·K; dielectric constant: 2.9 (test standard ASTMD150). Compared with the thermal conductive potting glue on the market, its dielectric constant is generally 4-8, and the thermal conductivity is between 0.8-1.5W / m·K. The product of the present invention has significant advantages in thermal conductivity and dielectric constant.

[0071] Thermal conductivity analysis: Thermal conductivity (1.1W / m·K) is a key parameter to measure the efficiency of heat conduction of materials, and determines the ability of materials to dissipate heat generated by electronic components. The advantages of the present invention in thermal conductivity mainly come from the following points: Optimized thermal conductive filler system: Thermal conductive fillers include spherical aluminum hydroxide (particle size of 50μm, 10μm, 1μm) and hexagonal boron nitride (particle size of 7μm), and these particles have high thermal conductivity. Through the design of reasonable particle size gradient and mass ratio (10:4:1:19), a tight stacking structure is formed between the fillers, which improves the density of the thermal conductive channel and optimizes the thermal conductivity efficiency. Interface compatibility between fillers and substrates: The filler is surface treated with triethoxysilane coupling agent to improve the interface bonding force between the filler and the silicon-based substrate and reduce the interface thermal resistance. Uniform dispersion: High-speed dispersion and vacuum stirring process make the filler more evenly dispersed in the matrix, avoid filler agglomeration or stratification, and ensure the stability and consistency of the overall thermal conductivity. Meeting the heat dissipation needs of electronic products: The thermal conductivity of 1.1W / m·K is sufficient to meet the heat dissipation needs of chips and other high-power components in most 5G devices, effectively reducing operating temperatures and extending component life.

[0072] Analysis of low dielectric constant: Dielectric constant (2.9) is an important indicator to measure the ability of a material to store charge in an electric field, which is crucial for high-frequency signal transmission equipment (such as 5G communications). The advantages of low dielectric constant are mainly reflected in the following aspects: High signal transmission efficiency: Low dielectric constant means that electromagnetic waves propagate faster in the material, with less signal attenuation, which is suitable for high-frequency transmission applications; Reduce signal interference: In a complex electromagnetic environment, a lower dielectric constant helps reduce interference between signals (crosstalk effect) and ensure signal integrity. This product can achieve such a low dielectric constant thanks to the following innovations: Filler selection and ratio optimization: Hexagonal boron nitride (BN) is used as an important component of thermal conductive filler. BN itself not only has excellent thermal conductivity, but also has the characteristics of low dielectric constant. It is an ideal high-performance filler. Selection of silicon-based main material: Low-polarity terminal vinyl polydimethylsiloxane is selected as the main silicon-based material, which significantly reduces the overall dielectric constant of the material. At the same time, after the segment structure and cross-linking density are optimized, the number of polar groups in the material is further reduced, reducing dielectric loss. Uniformly dispersed filler system: The uniform distribution and efficient filling of fillers in the matrix avoid the generation of microscopic voids and reduce the adverse effects of voids on dielectric properties.

[0073] The test results are better than general products on the market: compared with the common thermal conductive potting glue with a dielectric constant of 4-8 on the market, this product is significantly reduced to 2.9, making it more suitable for high-frequency applications in 5G and even 6G communications.

[0074] Advantages of this product in the field of 5G / 6G communications: Low dielectric constant meets high-frequency requirements: In 5G and future 6G devices, the signal frequency is higher (the frequency range is in the millimeter wave or even terahertz band), and the dielectric constant requirements for potting glue are lower. Products with a dielectric constant of only 2.9 can significantly reduce signal attenuation and loss, ensuring high-speed transmission performance. Excellent thermal conductivity:

[0075] With the increase in power consumption of 5G / 6G equipment, the demand for heat dissipation of chips and modules has increased significantly. This product can effectively solve the heat dissipation problem of high-power components and avoid performance degradation due to overheating. Good comprehensive performance: In addition to thermal conductivity and low dielectric constant, this product also has good anti-settling, wettability and mechanical properties, suitable for long-term use in complex environments. Meet the needs of future communication technology development: 5G / 6G technology development has put forward higher requirements for materials, especially low dielectric constant and high thermal conductivity. The performance indicators of this product have reached or even exceeded the current technical standards, and have broad market application prospects.

[0076] The two-component low dielectric constant thermally conductive potting glue of the present invention achieves a high thermal conductivity of 1.1W / m·K and an extremely low dielectric constant of 2.9 by optimizing the thermal conductive filler system, silicon-based main material and precise process control. It is significantly better than existing market products and is particularly suitable for high-frequency and high-power module applications in 5G / 6G communication equipment, providing a technical solution for future high-performance electronic materials.

[0077] The specific embodiments described herein are merely examples of the spirit of the present invention. A person skilled in the art of the present invention may make various modifications or supplements to the specific embodiments described or replace them in a similar manner, but will not deviate from the spirit of the present invention or exceed the defined scope. Although the present invention is described and described in detail in the foregoing description, such descriptions and descriptions are considered to be illustrative or exemplary rather than restrictive. It should be understood that within the scope of the following claims, changes and modifications may be made by a person of ordinary skill. Specifically, the present invention encompasses additional embodiments having any combination of features from the above-mentioned different embodiments. With respect to the use of the expression "generally" or "substantially", this patent application should be understood to disclose that these features and values ​​are also fully satisfied, i.e., there is no aforementioned characterization as "generally" or "substantially".

Claims

1. A method for preparing a two-component low dielectric constant thermally conductive potting adhesive, characterized in that: The two-component low dielectric constant thermal conductive potting glue comprises component A and component B. The preparation method of the two-component low dielectric constant thermal conductive potting glue comprises the following steps: S1: preparing an intermediate formula material: after uniformly mixing the vinyl-terminated polydimethylsiloxane and the triethoxysilane coupling agent, adding a thermal conductive filler to obtain a pre-treated mixture, and subjecting the pre-treated mixture to a first stirring operation, a first vacuum stirring operation, a first vacuum high-speed dispersion operation, a second vacuum stirring operation, and a second vacuum high-speed dispersion operation in sequence by a specific process; after the second vacuum high-speed dispersion operation is completed, an intermediate formula material is obtained. According to the weight ratio, the vinyl-terminated polydimethylsiloxane: triethoxysilane coupling agent: thermal conductive filler is 50-52: 1-1.1: 150-155; The thermal conductive filler includes spherical aluminum hydroxide with a particle size of 50um, spherical aluminum hydroxide with a particle size of 10um, spherical aluminum hydroxide with a particle size of 1um, and hexagonal boron nitride with a particle size of 6-8um. According to the weight ratio, the spherical aluminum hydroxide with a particle size of 50um: the spherical aluminum hydroxide with a particle size of 10um: the spherical aluminum hydroxide with a particle size of 1um: the hexagonal boron nitride is 10-11:4-4.5:1-1.1:18-20; In the first stirring operation, the parameters are set as follows: stirring speed is 20-22rpm, stirring temperature is 80-82℃; in the first vacuum stirring operation, the parameters are set as follows: stirring speed is 25-27rpm, stirring temperature is 118-122℃, in the first vacuum high-speed dispersion operation, the parameters are set as follows: stirring speed is 700-750rpm, stirring temperature is 118-122℃, in the second vacuum stirring operation, the parameters are set as follows: stirring speed is 30-32rpm, stirring temperature is 150-155℃; in the second vacuum high-speed dispersion operation, the parameters are set as follows: stirring speed is 1000-1050rpm, stirring temperature is 150-155℃; S2 prepares component A: take a certain amount of intermediate formula material, add platinum catalyst and colorant to the taken intermediate formula material to obtain component A mixture, and sequentially perform the first high-speed dispersion operation, the second high-speed dispersion operation, the third high-speed dispersion operation and the fourth high-speed dispersion operation on the component A mixture by using specific process 2, and after the fourth high-speed dispersion operation, component A is obtained, and the colorant is specifically black iron oxide; according to the weight ratio, the intermediate formula material: platinum catalyst: black iron oxide is 1000-1010:0.5-0.53:5-5.2; In the first high-speed dispersion operation, the stirring speed is 500-550rpm; in the second high-speed dispersion operation, the stirring speed is 700-750rpm, in the third high-speed dispersion operation, the stirring speed is 1050-1100rpm, and in the fourth high-speed dispersion operation, the stirring speed is 1150-1200rpm; S3 prepares component B: taking the same weight of the intermediate formula material as that in step S2, adding a crosslinking agent and an inhibitor to the taken intermediate formula material to obtain a component B mixture, and subjecting the component B mixture to a first high-speed dispersion operation, a second high-speed dispersion operation and a third high-speed dispersion operation in sequence by using a specific process three, and after the third high-speed dispersion operation is completed, component B is obtained, and according to the weight ratio, the intermediate formula material: crosslinking agent: inhibitor is 1000-1010:10-10.1:0.1-0.102; The crosslinking agent includes a side hydrogen-containing silicone oil with a hydrogen content of 0.3% and a double-end hydrogen-containing silicone oil with a hydrogen content of 0.1%. According to the weight ratio, the side hydrogen-containing silicone oil with a hydrogen content of 0.3% and the double-end hydrogen-containing silicone oil with a hydrogen content of 0.1% are 1:1; The inhibitor is acetylene cyclohexanol; In the first high-speed dispersion operation, the stirring speed is 600-650 rpm; in the second high-speed dispersion operation, the stirring speed is 700-750 rpm; in the third high-speed dispersion operation, the stirring speed is 900-950 rpm.

2. The method for preparing the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 1, characterized in that: In step S1, in the first stirring operation, first stir for 55-65 minutes, then scrape the sides and bottom, and continue stirring for 55-65 minutes; in the first vacuum stirring operation, the stirring time is 10-15 minutes; in the first vacuum high-speed dispersion operation, the stirring time is 115-125 minutes, and in the second vacuum stirring operation, the stirring time is 10-15 minutes; in the second vacuum high-speed dispersion operation, the stirring time is 115-125 minutes.

3. The method for preparing the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 1, characterized in that: In step S2, in the first high-speed dispersion operation, the stirring time is 10-12 minutes; in the second high-speed dispersion operation, the stirring time is 10-12 minutes; in the third high-speed dispersion operation, the stirring time is 30-32 minutes; in the fourth high-speed dispersion operation, the stirring time is 30-35 minutes.

4. The method for preparing the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 1, characterized in that: In step S3, in the first high-speed dispersion operation, the stirring time is 20-22 minutes; in the second high-speed dispersion operation, the stirring time is 20-25 minutes; in the third high-speed dispersion operation, the stirring time is 30-35 minutes.

5. The method for preparing the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 1, characterized in that: In the first mixing operation, the first vacuum mixing operation and the second vacuum mixing operation, planetary mixing equipment is used for mixing.

6. The method for preparing the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 1, characterized in that: For the first vacuum mixing operation, the first vacuum high-speed dispersion operation, during the second vacuum mixing operation and the second vacuum high-speed dispersion operation, the vacuum parameters are set as follows: the vacuum degree is not higher than 0.09MPa.

7. A method for using a two-component low dielectric constant thermally conductive potting adhesive, wherein the two-component low dielectric constant thermally conductive potting adhesive is prepared by the preparation method of any one of claims 1 to 6, characterized in that: After mixing component A and component B, a potting glue mixture is obtained, and the potting glue mixture is subjected to high-speed dispersion operation and vacuum degassing treatment operation in sequence to obtain a target potting glue, and the target potting glue is poured into the potting object by a layer-by-layer pouring method. After the pouring is completed, a curing operation is performed; according to the weight ratio, component A: component B is 1:

1.

8. The method for using the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 7, characterized in that: The specific steps of high-speed dispersion operation are as follows: Use a high-speed disperser to stir the potting glue mixture at a stirring speed of 500-550rpm for 5-7 minutes, and then scrape the edges and bottom. After the operation, keep the stirring speed unchanged and continue stirring for 5-6 minutes.

9. The method for using the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 7, characterized in that: The vacuum degassing treatment time is 5-7 minutes.

10. The method for using the two-component low dielectric constant thermally conductive potting adhesive as claimed in claim 7, characterized in that: In the curing operation, the curing temperature is 118-122°C and the curing time is 60-65 minutes.