High-thermal-conductivity insulating heat dissipation glue and preparation method thereof

Abstract

The invention discloses a high-thermal-conductivity insulating heat-dissipating adhesive and a preparation method thereof, and relates to the technical field of composite materials, the high-thermal-conductivity insulating heat-dissipating adhesive comprises the following components by weight: 23-27 parts of polyurethane resin, 63-67 parts of a thermal conductive filler, 3.5-4.5 parts of a flexibilizer, 3.5-4.5 parts of a curing agent, 1.3-1.7 parts of a coupling agent, and 0.4-0.6 part of an antifoaming agent. Compared with the prior art, the heat-dissipating adhesive has the advantages that silicon carbide and magnesium oxide are dispersed in the resin in a nanoscale mode through ultrasonic vibration, the particle size of filler is refined to be 5-15 microns, heat can be conducted and dissipated more effectively, and by combining the excellent insulating property of a polyurethane resin matrix, the heat-dissipating adhesive can maintain the high heat-conducting property and meanwhile has the good heat-dissipating effect. And good electrical insulation performance is ensured, so that the safety and the stability of electronic components during high-speed operation are ensured.

Description

Technical Field

[0001] The invention relates to the technical field of composite materials, in particular to a high thermal conductivity insulation heat dissipation adhesive and a preparation method thereof. Background Art

[0002] With the rapid development of electronic technology, the integration of electronic devices has been continuously improved, and the power consumption has also increased accordingly, which has put forward higher requirements on the heat dissipation performance of electronic components. Traditional heat dissipation materials are often difficult to ensure good electrical insulation performance while maintaining high thermal conductivity, thus limiting the stability and safety of electronic components under high-speed operation;

[0003] In the research and development of heat dissipation materials, the selection and dispersion technology of fillers is one of the key factors. Silicon carbide and magnesium oxide, as common inorganic fillers, are widely used in the preparation of heat dissipation materials due to their high thermal conductivity, stability and good mechanical properties. However, traditional mixing methods often make it difficult to achieve uniform dispersion of these fillers in the resin matrix, resulting in limited contact area between the filler and the resin and low heat conduction efficiency. We propose a high thermal conductivity insulating heat dissipation adhesive and its preparation method. Summary of the invention

[0004] The object of the present invention is to provide a high thermal conductivity insulation heat dissipation adhesive and a preparation method thereof.

[0005] In order to solve the problems raised in the above background technology, the present invention provides the following technical solutions: a high thermal conductivity insulating heat dissipation adhesive, the high thermal conductivity insulating adhesive comprising the following components in parts by weight: 23-27 parts by weight of polyurethane resin, 63-67 parts by weight of thermal conductive filler, 3.5-4.5 parts by weight of toughening agent, 3.5-4.5 parts by weight of curing agent, 1.3-1.7 parts by weight of coupling agent, and 0.4-0.6 parts by weight of defoaming agent.

[0006] As a further solution of the present invention: the thermal conductive filler is silicon carbide and magnesium oxide, and the composition of silicon carbide and magnesium oxide is 33-37 parts by weight of silicon carbide and 28-32 parts by weight of magnesium oxide, and the particle size range of the thermal conductive filler is 5-30 μm.

[0007] As a further solution of the present invention: the toughening agent is one of polyacrylic acid resin, polyester resin and polyether polyol.

[0008] As a further solution of the present invention: the curing agent is one of phthalic anhydride and phenolic resin.

[0009] As a further solution of the present invention: the coupling agent is one of aluminate and silane.

[0010] As a further solution of the present invention: the defoaming agent is one of polydimethylsiloxane and hydrophobic silica.

[0011] In addition, the present invention also provides a method for preparing a high thermal conductivity insulating heat dissipation adhesive, comprising the following steps:

[0012] Step 1: According to the above weight range, use a precision electronic scale to accurately weigh the raw materials of each component, put the polyurethane resin and the polyester resin into a reaction kettle with a stirring device, turn on the stirrer, stir at a moderate speed for 30 minutes, control the temperature at 15°C-30°C, and mix the two resins evenly;

[0013] Step 2: First, slowly add silicon carbide to the resin mixture, stir with a high-speed mechanical stirrer for 20 minutes, control the temperature at 15°C-30°C, and initially disperse the silicon carbide in the resin. Then add magnesium oxide and continue stirring for 30 minutes, control the temperature at 15°C-30°C, and ensure that the filler is evenly distributed in the resin without agglomeration.

[0014] Step 3: slowly pour the coupling agent into the mixture, increase the stirring speed, and continue stirring for 40 minutes. When the stirring is about to end, slowly add the curing agent and stir for 15 minutes to evenly disperse the curing agent in the mixture;

[0015] Step 4: Transfer the mixture to a vacuum degassing device, turn on the vacuum pump, perform vacuum treatment, set the vacuum degree to about -0.09 MPa, and degas for 1 hour. Pour the degassed mixture into a pre-prepared mold for molding. After molding, place the sample in a constant temperature drying oven for curing;

[0016] Step 5. Take out the heat dissipation glue sample, grind it into a disc shape, test the thermal conductivity with a thermal conductivity tester, test the insulation performance with an insulation resistance tester or a high-voltage tester, and test the mechanical properties with a tensile testing machine. Then compare the test data with the standard of the insulating heat dissipation glue to analyze and evaluate the product performance.

[0017] As a further solution of the present invention: in step 2, an ultrasonic transducer is placed at the bottom of the reactor, and ultrasonic vibration is used to disperse silicon carbide and magnesium oxide in the resin at the nanoscale, and stirring is continued under the action of ultrasound until the filler is completely and evenly dispersed and the particle size is refined to 5-15 μm.

[0018] As a further solution of the present invention: In the curing process of step 4, a two-stage temperature-controlled curing method is adopted, first pre-curing is carried out at 80°C for 0.5 hours to allow the curing agent to initially react with the resin to form a preliminary cross-linking network, and then the temperature is raised to 120°C for complete curing, which lasts for 1 hour.

[0019] By adopting the above technical solution, compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. The present invention uses ultrasonic vibration to disperse silicon carbide and magnesium oxide in the resin at the nano level, and refines the filler particle size to 5-15 μm, so that heat can be more effectively conducted and dissipated. Combined with the excellent insulation properties of the polyurethane resin matrix, the heat dissipation adhesive can maintain high thermal conductivity while ensuring good electrical insulation performance, thereby ensuring the safety and stability of electronic components during high-speed operation;

[0021] 2. The present invention adopts a two-stage temperature control curing method through the curing process, first pre-curing at 80°C to allow the curing agent to react with the resin to form a preliminary cross-linking network, and then raising the temperature to 120°C for complete curing. This method can ensure more complete and uniform curing and improve the mechanical properties and stability of the heat dissipation adhesive;

[0022] 3. The present invention uses polyurethane resin, silicon carbide and magnesium oxide as main raw materials, so that less waste is generated during the preparation process, the pollution load on the environment is reduced, and the cost of subsequent processing and recycling is reduced, thereby further improving resource utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the preparation method steps in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0025] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0026] Please refer to the attached Figure 1 The present invention discloses a high thermal conductivity insulating heat dissipation adhesive, which comprises the following components in parts by weight: 23-27 parts by weight of polyurethane resin, 63-67 parts by weight of thermal conductive filler, 3.5-4.5 parts by weight of toughening agent, 3.5-4.5 parts by weight of curing agent, 1.3-1.7 parts by weight of coupling agent, and 0.4-0.6 parts by weight of defoaming agent.

[0027] In one embodiment of the present invention, the thermal conductive filler is silicon carbide and magnesium oxide, and the composition of silicon carbide and magnesium oxide is 33-37 parts by weight of silicon carbide and 28-32 parts by weight of magnesium oxide. The particle size range of the thermal conductive filler is 5-30 μm.

[0028] In one embodiment of the present invention, the toughening agent is one of polyacrylic acid resin, polyester resin and polyether polyol.

[0029] In one embodiment of the present invention, the curing agent is one of phthalic anhydride and phenolic resin.

[0030] In one embodiment of the present invention: the coupling agent is one of aluminate and silane.

[0031] In one embodiment of the present invention, the defoaming agent is one of polydimethylsiloxane and hydrophobic silica.

[0032] The present invention also provides a method for preparing a high thermal conductivity insulating heat dissipation adhesive, comprising the following steps:

[0033] Step 1: According to the above weight range, use a precision electronic scale to accurately weigh the raw materials of each component, put the polyurethane resin and the polyester resin into a reaction kettle with a stirring device, turn on the stirrer, stir at a moderate speed for 30 minutes, control the temperature at 15°C-30°C, and mix the two resins evenly;

[0034] Step 2: First, slowly add silicon carbide to the resin mixture, stir with a high-speed mechanical stirrer for 20 minutes, control the temperature at 15°C-30°C, and initially disperse the silicon carbide in the resin. Then add magnesium oxide and continue stirring for 30 minutes, control the temperature at 15°C-30°C, and ensure that the filler is evenly distributed in the resin without agglomeration.

[0035] Step 3: slowly pour the coupling agent into the mixture, increase the stirring speed, and continue stirring for 40 minutes. When the stirring is about to end, slowly add the curing agent and stir for 15 minutes to evenly disperse the curing agent in the mixture;

[0036] Step 4: Transfer the mixture to a vacuum degassing device, turn on the vacuum pump, perform vacuum treatment, set the vacuum degree to about -0.09 MPa, and degas for 1 hour. Pour the degassed mixture into a pre-prepared mold for molding. After molding, place the sample in a constant temperature drying oven for curing;

[0037] Step 5. Take out the heat dissipation glue sample, grind it into a disc shape, test the thermal conductivity with a thermal conductivity tester, test the insulation performance with an insulation resistance tester or a high-voltage tester, and test the mechanical properties with a tensile testing machine. Then compare the test data with the standard of the insulating heat dissipation glue to analyze and evaluate the product performance.

[0038] In one embodiment of the present invention: in step 2, an ultrasonic transducer is placed at the bottom of the reactor, and ultrasonic vibration is used to disperse silicon carbide and magnesium oxide in the resin at the nanoscale, and stirring is continued under the action of ultrasound until the filler is completely and evenly dispersed and the particle size is refined to 5-15 μm.

[0039] In one embodiment of the present invention: During the curing process of step four, a two-stage temperature-controlled curing method is adopted. First, pre-curing is carried out at 80°C for 0.5 hours to allow the curing agent to initially react with the resin to form a preliminary cross-linked network. The temperature is then raised to 120°C for complete curing, which lasts for 1 hour.

[0040] Example 1, please refer to the attached Figure 1 , take 25 parts by weight of polyurethane resin, put it together with 4 parts by weight of toughening agent (polyester resin) into a reactor with a stirring device, turn on the stirrer, stir at a moderate speed, control the temperature to 25°C, and stir for 30 minutes to mix the two substances evenly. Then, slowly add 35 parts by weight of silicon carbide to the resin mixture, use a high-speed mechanical stirrer to stir, control the temperature to 25°C, and stir for 20 minutes to make the silicon carbide preliminarily dispersed in the resin. Then, add 30 parts by weight of magnesium oxide, continue stirring for 30 minutes, control the temperature to 25°C, ensure that the filler is evenly distributed in the resin without agglomeration, then slowly pour 1.5 parts by weight of coupling agent (silane) into the mixture, increase the stirring speed, and continue stirring for 40 minutes. When the stirring is about to end, slowly add 4 parts by weight of curing agent (phthalic anhydride), stir for 15 minutes, so that the curing agent is evenly dispersed in the mixture, and then convert the mixture to Move to the vacuum degassing equipment, turn on the vacuum pump, and perform vacuum treatment. The vacuum degree is set to about -0.09MPa, and the degassing time is 1 hour. Pour the degassed mixture into a pre-prepared mold for molding. After molding, put the sample into a constant temperature drying oven for curing. The curing process adopts a two-stage temperature control curing method. First, pre-curing is performed at 80°C for 0.5 hours to allow the curing agent to initially react with the resin to form a preliminary cross-linking network. Then the temperature is raised to 120°C for complete curing, which lasts for 1 hour. Finally, take out the heat dissipation glue sample, grind it into a disc shape, test the thermal conductivity using a thermal conductivity tester, test the insulation performance using an insulation resistance tester or a high-voltage tester, and test the mechanical properties using a tensile testing machine. The test results are as follows: thermal conductivity 2.5 (W / (m·K)), insulation resistance 100MΩ, tensile strength 15MPa, and the amount of waste generated accounts for about 5% of the total mass.

[0041] Example 2, please refer to the attached Figure 1, weigh 23 parts by weight of polyurethane resin, select polyether polyol as a toughening agent, take 3.5 parts by weight and put it into a reactor, mix and stir with the polyurethane resin, the stirring temperature is 15°C, the stirring time is 30 minutes, slowly add 33 parts by weight of silicon carbide to the resin mixture, the stirring temperature is 15°C, the stirring time is 20 minutes, then add 28 parts by weight of magnesium oxide, continue stirring for 30 minutes, control the temperature to 15°C, slowly pour 1.3 parts by weight of coupling agent (aluminate) into the mixture, stir for 40 minutes and then add 3.5 parts by weight of curing agent (phenolic resin) were stirred for 15 minutes, and the mixture was vacuum degassed with a vacuum degree of -0.09 MPa and a degassing time of 1 hour. After being poured into a mold for forming, it was placed in a constant temperature drying oven for curing. It was pre-cured at 80°C for 0.5 hour, and then heated to 120°C for complete curing for 1 hour. The performance of the prepared heat dissipation adhesive sample was tested, with a thermal conductivity of 2.3 (W / (m·K)), an insulation resistance of 90MΩ, a tensile strength of 14MPa, and the amount of waste generated accounted for about 4.5% of the total mass.

[0042] Example 3, please refer to the attached Figure 1 , prepare 27 parts by weight of polyurethane resin, use polyacrylic acid resin as a toughening agent, take 4.5 parts by weight and mix with polyurethane resin in a reactor, stir at a stirring temperature of 30°C, and stir for 30 minutes. First, add 37 parts by weight of silicon carbide, stir at a temperature of 30°C for 20 minutes, then add 32 parts by weight of magnesium oxide, continue stirring for 30 minutes, pour in 1.7 parts by weight of coupling agent (silane), stir for 40 minutes, then add 4.5 parts by weight of curing agent (phthalic anhydride), stir for 15 minutes, vacuum degas the mixture, the vacuum degree is -0.09MPa, the degassing time is 1 hour, pour it into the mold for molding, and use two-stage temperature control for curing, pre-curing at 80°C for 0.5 hour, and fully curing at 120°C for 1 hour. The performance of the prepared heat dissipation adhesive sample is tested, the thermal conductivity is 2.4 (W / (m·K)), the insulation resistance is 95MΩ, the tensile strength is 14.5MPa, and the amount of waste generated accounts for about 4.8% of the total mass.

[0043] Specifically, ultrasonic vibration is used to disperse silicon carbide and magnesium oxide in the resin at the nanoscale, and the filler particle size is refined to 5-15μm, so that heat can be conducted and dissipated more effectively. Combined with the excellent insulating properties of the polyurethane resin matrix, the heat dissipation adhesive can maintain high thermal conductivity while ensuring good electrical insulation performance, thereby ensuring the safety and stability of electronic components during high-speed operation.

[0044] Specifically, a two-stage temperature-controlled curing method is adopted in the curing process. First, pre-curing is performed at 80°C to allow the curing agent to initially react with the resin to form a preliminary cross-linking network, and then the temperature is raised to 120°C for complete curing. This method can ensure more complete and uniform curing, and improve the mechanical properties and stability of the heat dissipation adhesive.

[0045] Specifically, by using polyurethane resin, silicon carbide and magnesium oxide as the main raw materials, less waste is generated during the preparation process, the pollution load on the environment is reduced, and the cost of subsequent processing and recycling is reduced, further improving the efficiency of resource utilization.

[0046] The above-mentioned front, back, left, right, top and bottom are all based on the figures in the specification. Figure 1 As a benchmark, according to the person's observation perspective, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0047] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present invention.

[0048] It should be noted that the device structure and the drawings of the present invention mainly describe the principle of the present invention. In terms of the technology of the design principle, the settings of the power mechanism, power supply system and control system of the device are not fully described. On the premise that the technical personnel in this field understand the principle of the above invention, the details of the power mechanism, power supply system and control system can be clearly known. The control method of the application document is automatic control through a controller, and the control circuit of the controller can be realized by simple programming by the technical personnel in this field.

[0049] The standard parts used therein can all be purchased from the market and can be customized according to the instructions and drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. The machinery, parts and equipment all adopt conventional models in the prior art, and the structures and principles of the components known to technical personnel in this field can be known by these technical personnel through technical manuals or through conventional experimental methods.

[0050] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations are made to these embodiments without departing from the principle and spirit of the present invention, and they still fall within the protection scope of the present invention.

Claims

1. A high thermal conductivity insulation heat dissipation adhesive, characterized in that: The high thermal conductive insulating adhesive comprises the following components in parts by weight: 23-27 parts by weight of polyurethane resin, 63-67 parts by weight of thermal conductive filler, 3.5-4.5 parts by weight of toughening agent, 3.5-4.5 parts by weight of curing agent, 1.3-1.7 parts by weight of coupling agent, and 0.4-0.6 parts by weight of defoaming agent.

2. The high thermal conductivity insulation heat dissipation adhesive according to claim 1, characterized in that: The thermal conductive filler is silicon carbide and magnesium oxide, and the composition of silicon carbide and magnesium oxide is 33-37 parts by weight of silicon carbide and 28-32 parts by weight of magnesium oxide. The particle size range of the thermal conductive filler is 5-30 μm.

3. The high thermal conductivity insulation heat dissipation adhesive according to claim 1, characterized in that: The toughening agent is one of polyacrylic acid resin, polyester resin and polyether polyol.

4. The high thermal conductivity insulating heat dissipation adhesive according to claim 1, characterized in that: The curing agent is one of phthalic anhydride and phenolic resin.

5. The high thermal conductivity insulation heat dissipation adhesive according to claim 1, characterized in that: The coupling agent is one of aluminate and silane.

6. The high thermal conductivity insulation heat dissipation adhesive according to claim 1, characterized in that: The defoaming agent is one of polydimethylsiloxane and hydrophobic silica.

7. A method for preparing a high thermal conductivity insulating heat dissipation adhesive suitable for any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: According to the above weight range, use a precision electronic scale to accurately weigh the raw materials of each component, put the polyurethane resin and the polyester resin into a reaction kettle with a stirring device, turn on the stirrer, stir at a moderate speed for 30 minutes, control the temperature at 15°C-30°C, and mix the two resins evenly; Step 2: First, slowly add silicon carbide to the resin mixture, stir with a high-speed mechanical stirrer for 20 minutes, control the temperature at 15°C-30°C, and initially disperse the silicon carbide in the resin. Then add magnesium oxide and continue stirring for 30 minutes, control the temperature at 15°C-30°C, and ensure that the filler is evenly distributed in the resin without agglomeration. Step 3: slowly pour the coupling agent into the mixture, increase the stirring speed, and continue stirring for 40 minutes. When the stirring is about to end, slowly add the curing agent and stir for 15 minutes to evenly disperse the curing agent in the mixture; Step 4: Transfer the mixture to a vacuum degassing device, turn on the vacuum pump, perform vacuum treatment, set the vacuum degree to about -0.09 MPa, and degas for 1 hour. Pour the degassed mixture into a pre-prepared mold for molding. After molding, place the sample in a constant temperature drying oven for curing; Step 5. Take out the heat dissipation glue sample, grind it into a disc shape, test the thermal conductivity with a thermal conductivity tester, test the insulation performance with an insulation resistance tester or a high-voltage tester, and test the mechanical properties with a tensile testing machine. Then compare the test data with the standard of the insulating heat dissipation glue to analyze and evaluate the product performance.

8. The method for preparing a highly thermally conductive insulating heat dissipating adhesive according to claim 7, characterized in that: In the step 2, an ultrasonic transducer is placed at the bottom of the reactor, and ultrasonic vibration is used to disperse silicon carbide and magnesium oxide in the resin at the nanoscale, and stirring is continued under the action of ultrasound until the filler is completely and evenly dispersed and the particle size is refined to 5-15 μm.

9. The method for preparing a high thermal conductivity insulating heat dissipation adhesive according to claim 7, characterized in that: During the curing process of step 4, a two-stage temperature-controlled curing method is adopted. First, pre-curing is carried out at 80°C for 0.5 hours to allow the curing agent to initially react with the resin to form a preliminary cross-linking network. The temperature is then raised to 120°C for complete curing, which lasts for 1 hour.

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