Process for preparing heat-resistant, high-tack, high-conductive acrylate resin adhesive

Abstract

The application relates to a preparation method of heat-resistant, high-adhesion, high-conductivity acrylate resin glue and relates to the technical field of conductive glue. An acrylate resin, a carbon nanotube dispersion liquid, an epoxy resin dispersion, diethylenetriamine, 2-ethyl-4-methyl imidazole and acetone are stirred and uniformly mixed to obtain a mixture A; an antioxidant, conductive silver powder and a coupling agent are added into the mixture A and uniformly stirred to obtain a mixture B; the mixture B is defoamed under a vacuum degree of less than -0.095 MPa for 10 min to obtain heat-resistant, high-dispersibility, self-repairing, high-adhesion conductive glue; the obtained conductive glue has a mass loss rate of less than 6.65%, a peeling strength of higher than 3.82 N / cm and a volume resistivity of less than 6.35*10 ‑5 Omega*cm, and exhibits good heat resistance, adhesion and relatively low volume resistivity.

Description

Technical Field

[0001] This invention relates to a method for preparing conductive adhesives, specifically a method for preparing a heat-resistant, highly adhesive, and highly conductive acrylate resin adhesive. Background Technology

[0002] With the continuous development of electronic technology, especially in high-frequency, high-density, and miniaturized electronic devices, traditional solder materials face many challenges. Although solder is widely used in electronic assembly, in applications requiring high performance, vibration resistance, and high-frequency stability, solder is prone to fatigue failure, thermal stress problems, and degradation of conductivity.

[0003] Conductive adhesive is a type of adhesive that becomes conductive after curing or drying, enabling the bonding of various conductive materials and creating an electrical path between them. In the electronics industry, conductive adhesive has become an indispensable key material. As a substitute for solder, conductive adhesive, due to its excellent conductivity, good temperature resistance, and operational flexibility, is gradually becoming a core technology in high-performance electronic assembly. Conductive adhesive not only replaces solder but also effectively solves problems such as heat damage and soldering defects during the soldering process.

[0004] Conductive adhesives typically consist of conductive fillers, adhesive matrices, and solvents. Fillers are primarily silver, copper, gold, nickel, and carbon-based materials, with silver powder being the most commonly used. Adhesive matrices commonly include epoxy resins, silicone rubbers, polyurethanes, and acrylates, with epoxy resins being the most prevalent. Solvents often include water, alcohols, ketones, and esters. Epoxy resin matrices offer high adhesion and heat resistance, making them suitable for precision chip bonding, printed circuit board component bonding, rigid connections of metal electrodes, and conductive connections in high-temperature environments. However, for flexible / wearable electronics and other fields, while acrylate resins offer excellent flexibility and fast curing speeds, adding conductive fillers increases material rigidity while improving conductivity, leading to a decrease in flexibility and peel strength, making it difficult to balance high conductivity and high flexibility. Furthermore, conventional acrylic resins have a high film-forming shrinkage rate (approximately 5%~10%), which compromises mechanical properties (such as adhesion and crack resistance), electrical properties (such as conductivity stability), and long-term reliability (such as aging resistance and migration resistance), limiting their application in scenarios requiring both high conductivity and high flexibility. Additionally, conventional acrylic conductive adhesives have poor heat resistance, easily decomposing or degrading under prolonged high temperatures, and their adhesive strength is relatively weak, necessitating improvements.

[0005] Invention patent CN116102989B discloses a fast-curing acrylic adhesive, prepared from the following raw materials in parts by weight: 13-17 parts of methacrylate-terminated nitrile rubber, 5-8 parts of polyurethane acrylate, 14-20 parts of monofunctional acrylate monomer, 7-13 parts of difunctional acrylate monomer, 1-3 parts of trifunctional acrylate monomer, 0.5-1.5 parts of peroxide, 0.01-0.04 parts of polymerization inhibitor, and 0.5-0.7 parts of coupling agent. The acrylic adhesive provided by this invention has the advantages of fast curing, low volume resistivity after curing with added silver powder, good bonding strength, and moderate elastic modulus. It can be used as conductive silver adhesive for photovoltaic shingled tiles, with a minimum volume resistivity of 3.2 × 10⁻⁶. -4 The value is Ω·cm, but no improvement in heat resistance is mentioned.

[0006] Invention patent CN113231760B discloses a conductive adhesive film composed of a soldering binder and tin-based metal powder. By mass percentage, the tin-based metal powder accounts for 0.1% to 30%, and the soldering binder accounts for 70% to 99.9%. The soldering binder, by mass percentage, includes 30% to 70% solvent, 45% to 65% resin tackifier, 1% to 5% organic acid activator, and 0.1% to 1% surfactant. The resin tackifier, by mass percentage, includes 0.1% to 0.5% peroxide initiator, 0.5% to 5% curing agent, and 94.5% to 99% resin. The tin-based metal powder content range in this patent is relatively higher than in existing technologies. By adding an organic acid activator to the soldering binder, the influence of the oxide film on the surface of the tin-based metal powder on the formation of metallurgical connections is effectively balanced, improving the metallurgical connection effect. Although this patent uses acrylate monomers, it does not address improvements to the heat resistance, high adhesion, and high conductivity of acrylate resins.

[0007] In summary, existing technologies have not yet simultaneously addressed the shortcomings of acrylate resins in terms of heat resistance, high adhesion, high conductivity, and curing shrinkage. Improvements in these properties are particularly important when these resins are applied in the field of flexible electronics. Summary of the Invention

[0008] This invention mainly addresses the defects of acrylate conductive adhesives, such as poor heat resistance, poor adhesion, and poor conductivity, while also solving the problem of high film shrinkage during film formation and curing.

[0009] The preparation method of heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive is as follows: (1) 25-30 parts of acrylic resin, 4-5 parts of carbon nanotube dispersion, 5-8 parts of epoxy resin dispersion, 2.6-3.0 parts of diethylenetriamine, 0.7-0.9 parts of 2-ethyl-4-methylimidazole, and 16-25 parts of acetone are stirred and mixed evenly to obtain mixture A; (2) 0.3-0.7 parts of antioxidant, 52-65 parts of conductive silver powder, and 0.4-1.9 parts of coupling agent are added to mixture A and stirred evenly to obtain mixture B; (3) Mixture B is degassed under a vacuum degree <-0.095MPa for 10 minutes to obtain heat-resistant, highly dispersible, self-healing, and highly adhesive conductive adhesive.

[0010] The preparation method of the acrylate resin is as follows:

[0011] (1) Preparation of core layer emulsion: Add 40-70 g of water, 12-18 g of emulsifier A and 20-45 g of methacrylic acid to the reaction vessel, mix and stir evenly, heat to 50-60 ℃, stir for 45-60 min, then add monomer A, 13.4-14.5 g of DOPO and 5.88-6.12 g of maleic anhydride, stir for 30-40 min; heat to 65 ℃ and reflux water, continue to heat to 70-90 ℃, add 1-1.5 g of potassium persulfate initiator dropwise, add over a time of 0.5-1.0 h, react for 1-2 h to obtain core layer emulsion;

[0012] (2) Simultaneously add monomer B and initiator potassium persulfate 1-2 g to the core emulsion obtained in step (1) over a period of 1-1.5 h. Maintain the reaction temperature at 75-85 °C with stirring for 1-1.5 h. Then add diisopropanolamine 7.9-8.1 g and p-toluenesulfonic acid 0.32 g, and react at 70-85 °C for 1-3 h. Next, add tetramethylphosphoric acid 36.5-37.6 g and diethylthiophosphoric acid 2.8-3.1 g, and react at 70-80 °C with stirring for 1-2 h. Then add zirconium sulfate 2.8-3.4 g, aspartic acid 0.13-0.24 g, and 1H-indole-2-carboxamide 0.11-0.31 g. Cool to 40 °C, add emulsifier AEO-9 14-21 g and softener 2.1-3.5 g, and react for 30-60 h. min, add ammonia to adjust the pH to 7-8, distill under reduced pressure to 70% solid content to obtain acrylate resin;

[0013] The monomer A is composed of 33-60 g of ethyl acrylate, 22-38 g of methyl methacrylate, 5-7 g of styrene and 1-3 g of vinyl-terminated fluororubber;

[0014] The monomer B is composed of 20-70 g of methyl methacrylate, 51-86 g of ethyl acrylate, 3-5 g of styrene and 1-3 g of vinyl-terminated fluororubber.

[0015] The emulsifier A is a mixture of sodium dodecylbenzenesulfonate and AEO-9 in a weight ratio of 2.5:1.

[0016] The fabric softener is prepared as follows: 0.2-0.4 g of chloroplatinic acid and 6-8 g of isopropanol are added to a four-necked flask, the temperature is raised to 70-80 °C, 2.2 g of terminal hydrogen silicone oil and 25-36 g of allyl epoxy polyether are slowly added dropwise over a period of 1 h, glacial acetic acid is added to maintain the pH of the system at 5-6, and the reaction is carried out at 90-100 °C for 2-4 h to obtain intermediate A; 11-13 g of polyetheramine D400 and 1.3-2.4 g of ethylboric acid are added to intermediate A, the pH of the system is maintained at 5-6, and the reaction is carried out at 75-90 °C for 2-5 h, and the fabric softener is obtained after cooling.

[0017] The method for preparing the terminal vinyl fluorine rubber is as follows:

[0018] (1) Add 60 g of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer and 500-600 mL of acetone to a 2 L three-necked flask and let it stand at room temperature for 24 h. Then stir it for 30-60 min at 200-300 r / min until the copolymer is fully dissolved. Control the system temperature at 15 ℃, add 2.28 g of benzyltriethylammonium chloride and stir for 5-10 min. Add 20-24 g of 30% hydrogen peroxide aqueous solution and stir for 5 min. Then add 10.8 mL of 16 mol / L potassium hydroxide aqueous solution and stir for 5 min. Place the three-necked flask in a 24 ℃ oil bath and stir for 3-7 h. Stop the reaction and let it stand overnight. Acidify the reaction product and then add 5 times the volume of deionized water. The system separates into layers, with the upper layer being the aqueous phase and the lower layer being the organic phase. Small bubbles continuously rise from the organic phase to the aqueous phase. After the small bubbles completely disappear, collect the organic phase product and place it in a 60 ℃ oil bath. The system was dried in a vacuum oven at ℃ for 24 h to remove moisture, resulting in a pale yellow viscous liquid AEF with a number-average molecular weight of 2200 g / mol.

[0019] (2) Take 10 g of AEF obtained in step (1) and place it in a three-necked flask. Add 100 mL of acetone to dissolve it. After AEF is completely dissolved, add 0.8~1.0 g of silver carbonate, 1.7~2.1 g of allyl sulfone and 0.5~0.8 g of potassium persulfate to the three-necked flask in sequence. React at 30~65 ℃ for 2~4 h under mechanical stirring. After the reaction is completed, collect the product, wash it with deionized water to settle it 2~3 times, and dry the product under vacuum at 65 ℃ to constant weight to obtain vinyl-terminated fluororubber.

[0020] The epoxy resin dispersion is prepared by adding 4-6 g of boron nitride (particle size of about 1-10 μm) to 23 g of furfuryl alcohol glycidyl ether and sonicating in an ice-water bath for 1-1.5 h to obtain a uniformly dispersed boron nitride dispersion. Then, 110-130 g of epoxy resin E51 is added and stirred at 500-1000 r / min for 0.5-1.5 h to obtain the epoxy resin dispersion.

[0021] The conductive silver powder is composed of flake silver powder and spherical silver powder in a weight ratio of 2.5:1 to 3.6:1.

[0022] The carbon nanotube dispersion is prepared as follows: 1 g of carbon nanotubes, 0.1-0.6 g of ultralong carbon nanotubes, and 1.0-1.6 g of dispersant are added to 75 g of deionized water and stirred at 500-1200 r / min to completely wet the carbon nanotubes; then 1.4-2.7 g of p-hydroxybenzaldehyde is added, and the dispersion is further carried out using an ultrasonic cell disruptor with an output power of 600-700 W and an ultrasonic dispersion time of 10-50 min; finally, the dispersion is centrifuged at 900-1200 r / min for 15-30 min to obtain the carbon nanotube dispersion.

[0023] The dispersant is a mixture of sodium glycocholate, glycerol, dodecyl dimethyl betaine, and aminoacetic acid in a weight ratio of 3:1~1.5:0.3~0.5:0.4~0.45. The coupling agent is any one of KH550, KH560, KH792, and KH570, or a mixture of any two in any proportion. The antioxidant is any one of antioxidant 264 and p-hydroxyanisole, or a mixture of any two in any proportion.

[0024] The advantages of this invention are:

[0025] (1) To address the problem of poor heat resistance, flame retardant components, hexagonal boron nitride, carbon nanotubes and end-vinyl fluororubber are introduced for modification treatment; to address the defect of poor adhesion, epoxy resin is dispersed between the macromolecules of acrylate resin, cross-penetrating and entangled with each other, playing a role of mutual penetration and synergy, thereby improving the adhesion of acrylate resin; to address the problem of poor conductivity, flake silver powder and spherical silver powder are used in combination, and carbon nanotubes and ultra-long carbon nanotubes are used for dispersion stabilization treatment; to address the disadvantage of high film shrinkage rate of acrylate resin, the rigidity of monomer styrene, the toughness of softener and the elasticity of end-vinyl fluororubber are utilized to make its shrinkage rate decrease only slightly during curing.

[0026] (2) This invention employs a core-shell emulsion polymerization method to polymerize acrylate resins. In the core layer, utilizing a free radical reaction mechanism, the phosphorus-hydrogen bond in DOPO (9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) undergoes an addition reaction with the carbon-carbon double bond on maleic anhydride and the double bond of the acrylate monomer, thus incorporating it into the acrylate resin chain segment. In the shell layer, a ring-opening or esterification reaction occurs with the NH bond and hydroxyl group in diisopropanolamine. The resulting compound further reacts with the hydroxyl group in tetramethylolphosphine sulfate, improving the flexibility of the flame retardant through branching. Simultaneously, the remaining hydroxyl groups in the system undergo a complexation reaction with zirconium in zirconium sulfate, introducing highly heat-resistant zirconium sulfate into the system. Aspartic acid and 1H-indole-2-carboxamide in the system enhance the bonding between zirconium sulfate and the flame retardant system, strengthening the heat resistance of the flame retardant, connecting the core and shell layers, and improving the heat resistance of the acrylate resin. DOPO provides both the char source and the acid source, maleic anhydride provides the char source, and diisopropanolamine provides the gas source. When the flame retardant decomposes upon heating, it produces non-flammable gases such as ammonia and nitrogen oxides. These gases encapsulate the system, isolating it from air and reducing the contact area with the combustion-supporting agent, thus achieving flame retardancy. Simultaneously, the heat-decomposition of the flame retardant continuously produces acidic substances such as polyphosphoric acid and metaphosphoric acid, promoting carbonization of the material surface and forming a dense, porous char layer and zirconium layer. This slows down combustion and inhibits smoke release. Furthermore, the phosphorus in DOPO can capture oxygen free radicals released from combustibles, reducing the likelihood of combustion.

[0027] (3) Flake-shaped silver powder, such as fish scales or leaves, is more likely to form a dense conductive network through physical contact, sliding, and stacking; however, flake-shaped silver powder has high surface energy and strong van der Waals forces between flakes, making it prone to surface-to-surface stacking and agglomeration, which affects the smoothness of the colloidal film surface. In this invention, flake-shaped silver powder is used as a "conductive skeleton" or "conductive pathway", and spherical silver powder is used as a "conductive filler" to fill the gaps, grooves, and uncontacted areas between the flake-shaped silver powder, connecting the tiny gaps between the flake-shaped structures like "balls" and repairing the breaks in the conductive network. At a given total silver content, a more tightly connected, less defective, and less anisotropic three-dimensional network can be formed, resulting in higher and more stable conductivity. The "ball effect" of spherical particles can significantly reduce the viscosity of the mixture, improve fluidity, and make the conductive adhesive easier to stir and degas. Furthermore, spherical particles can separate flake powder, reducing the probability of surface-to-surface contact, thereby alleviating agglomeration, improving storage stability, and making the filler distribution more uniform. The addition of spherical particles can also play a role in stress buffering and dispersion, improving the toughness, impact resistance, and fatigue resistance of the adhesive layer.

[0028] (4) Due to the high aspect ratio of carbon nanotubes, they can overlap with each other to form a three-dimensional conductive network that runs through the entire colloid with extremely low addition amounts. Since the contact between carbon nanotubes is a line contact or a surface contact, electrons can tunnel through more easily. On the one hand, a very small amount of addition is required to achieve conductivity, and the uniformly dispersed carbon nanotube network can provide isotropic conductivity, thereby reducing the amount of silver used and controlling costs; on the other hand, the carbon nanotube network itself is flexible and can deform with the matrix without easily breaking, so that the resistance of the conductive adhesive changes very little after bending and stretching cycles, which meets the requirements of flexible electronics and wearable devices; in addition, carbon nanotubes have extremely high axial thermal conductivity. Introducing carbon nanotubes into the conductive adhesive can not only conduct electricity, but also significantly improve the thermal conductivity of the colloid, which helps the heat dissipation of components and improves reliability and lifespan.

[0029] (5) The electrical and thermal conductivity of carbon nanotubes is improved through the synergistic effect of carbon nanotubes and ultra-long carbon nanotubes (the ultra-long carbon nanotubes of this invention are prepared according to Example 1 of Chinese Invention Patent CN202211361272.5). To address the potential aggregation problem of ultra-long carbon nanotubes, this invention effectively dissociates aggregated carbon nanotubes from the aggregates through the synergistic effect of electrostatic repulsion and steric hindrance of dispersant molecules, forming a uniformly dispersed carbon nanotube dispersion. Specifically, glycerol and sodium glycocholate interact through hydrogen bonds and non-covalent bonds to form a stable adsorption layer on the surface of carbon nanotubes, achieving functional group modification and micronization; dodecyl dimethyl betaine reduces the surface tension of carbon nanotubes, promoting their wetting and dispersion in the solvent; glycine regulates the ionic environment of the system, maintaining the stability of the dispersion system. Glycerol and sodium glycocholate, as dispersing stabilizers for ultra-long carbon nanotubes, exert a synergistic effect of small molecule desorption and large molecule steric hindrance, constructing a multi-scale molecular film structure dispersion system. This composite structure allows small dispersant molecules to penetrate the interior of ultralong carbon nanotube aggregates, bind to the tube walls, and disrupt the original aggregation driving force. Simultaneously, a steric hindrance layer is formed on the surface of the monodispersed ultralong carbon nanotubes, effectively inhibiting secondary aggregation. Furthermore, ultrasonic treatment and the addition of p-hydroxybenzaldehyde further disperse potentially agglomerated carbon nanotubes, reducing the likelihood of aggregation and improving the dispersion stability. The resulting carbon nanotubes and ultralong carbon nanotubes are uniformly distributed within the voids of the conductive silver powder, synergistically enhancing the conductivity of the conductive silver powder.

[0030] (6) During combustion, hexagonal boron nitride migrates to the surface of the material, forming a dense and stable ceramic-like protective layer. This layer acts as a physical shield, free radical capture, and thermal / oxygen barrier, effectively delaying or preventing combustion and significantly reducing the release of toxic fumes and gases. Furfuryl alcohol glycidyl ether is dispersed in epoxy resin, and then dispersed in conductive adhesive based on the viscosity of the epoxy resin, improving the thermal conductivity of the conductive adhesive material and extending its service life.

[0031] (7) The double bonds of allyl epoxy polyether react with hydrogen in the terminal hydrogen silicone oil under the action of chloroplatinic acid catalyst to form a compound with epoxy bonds at both ends, introducing flexible silicone oil into the molecular chain. At the same time, the reaction of polyetheramine with epoxy bonds forms a silicon-hydrogen bond conversion product. Under the action of ethylboric acid, the reaction between epoxy bonds and polyetheramine is enhanced, improving its hydrophilicity. This softener disperses epoxy resin between acrylate resin macromolecules, allowing cross-penetration and mutual entanglement, playing a mutually penetrating and synergistic role, reducing entanglement resistance, which is conducive to its good dispersion and improving thermal conductivity.

[0032] (8) The vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer is oxidized and degraded into liquid carboxyl-terminated fluororubber, wherein H2O2 is used as the oxidant, and the product of the oxidation reaction is water, which facilitates post-treatment; potassium persulfate homolytic cracking produces S2O8. 2- S2O8 2- Ag + Oxidation into highly reactive Ag 2+ Intermediate; Acetic acid fragment in AEF in Ag 2+ Under the action of oxidation, it rapidly decarboxylates, releasing CO2 and forming fluoroalkyl radicals; the fluoroalkyl radicals continue to attack allyl sulfones to obtain benzenesulfonyl intermediates, and finally, through elimination reaction, terminal vinyl fluororubber is obtained. Detailed Implementation

[0033] The flake silver powder was from Ningbo Jinlei Nanomaterials Technology Co., Ltd. (item number: JL-Ag-N20); the spherical silver powder was from Zhejiang Manli Nanotechnology Co., Ltd. (item number: ML-Ag-N20); 1H-indole-2-carboxamide was purchased from Zhengzhou Alpha Chemical Co., Ltd.; the terminal hydrogen silicone oil was a product of Huawi Ruike Chemical Co., Ltd., with a molecular weight of 208.4 g / mol; the allyl epoxy polyether was APE600 from Guangdong Yunxing Biotechnology Co., Ltd.; the vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer (mass ratio of 65 / 15 / 20) with a number average molecular weight of 14000 was purchased from Zhonghao Chenguang Chemical Research Institute; parts are by weight, corresponding to g, Kg, etc.

[0034] The invention will be further illustrated below with examples.

[0035] Example 1

[0036] The preparation method of heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive is as follows: (1) 25 parts of acrylic resin, 4 parts of carbon nanotube dispersion, 5 parts of epoxy resin dispersion, 2.6 parts of diethylenetriamine, 0.7 parts of 2-ethyl-4-methylimidazole, and 16 parts of acetone are stirred evenly to obtain mixture A; (2) 0.3 parts of antioxidant 264, 52 parts of conductive silver powder, and 0.4 parts of coupling agent KH550 are added to mixture A and stirred evenly to obtain mixture B; (3) Mixture B is degassed for 10 minutes under a vacuum degree <-0.095MPa to obtain heat-resistant, highly dispersible, self-healing, and highly adhesive conductive adhesive.

[0037] The preparation method of acrylate resins is as follows:

[0038] (1) Preparation of core layer emulsion: Add 40 g of water, 12 g of emulsifier A (made by mixing sodium dodecylbenzenesulfonate and AEO-9 at a mass ratio of 2.5:1) and 20 g of methacrylic acid to the reaction vessel, mix and stir evenly, heat to 50 ℃, stir for 45 min, then add monomer A, 13.4 g of DOPO and 5.88 g of maleic anhydride, stir for 30 min; heat to 65 ℃ and reflux water, continue to heat to 70 ℃, add 1 g of potassium persulfate initiator (dissolved in 10 g of water) dropwise, add for 0.5 h, react for 1 h to obtain core layer emulsion;

[0039] (2) Add monomer B and 1 g of potassium persulfate (dissolved in 7 g of water) dropwise to the core emulsion obtained in step (1) for 1 h. Keep the mixture at 75 °C and stir for 1 h. Then add 7.9 g of diisopropanolamine and 0.32 g of p-toluenesulfonic acid and react at 70 °C for 1 h. Then add 36.5 g of tetrahydroxymethylphosphoric acid and 2.8 g of diethylthiophosphoric acid and stir for 1 h at 70 °C. Then add 2.8 g of zirconium sulfate, 0.13 g of aspartic acid and 0.11 g of 1H-indole-2-carboxamide. Cool the mixture to 40 °C, add 14 g of emulsifier AEO-9 and 2.1 g of softener and react for 30 min. Add ammonia to adjust the pH to 7-8 and distill under reduced pressure until the solid content is 70% to obtain acrylate resin.

[0040] Monomer A is composed of 33 g of ethyl acrylate, 22 g of methyl methacrylate, 5 g of styrene, and 1 g of vinyl-terminated fluororubber;

[0041] Monomer B is a mixture of 20 g of methyl methacrylate, 51 g of ethyl acrylate, 3 g of styrene and 1 g of vinyl-terminated fluororubber.

[0042] Preparation method of fabric softener: Add 0.2 g of chloroplatinic acid and 6 g of isopropanol to a four-necked flask, heat to 70 ℃, slowly add 2.2 g of terminal hydrogen silicone oil and 25 g of allyl epoxy polyether dropwise over 1 h, add glacial acetic acid to maintain the pH of the system at 5-6, react at 90 ℃ for 2 h to obtain intermediate A; continue to add 11 g of polyetheramine D400 and 1.3 g of ethylboric acid to intermediate A, maintain the pH of the system at 5-6, react at 75 ℃ for 2 h, and obtain fabric softener after cooling.

[0043] The preparation method of vinyl-terminated fluororubber is as follows:

[0044] (1) Add 60 g of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer and 500 mL of acetone to a 2 L three-necked flask and let it stand at room temperature for 24 h. Then stir for 30 min under mechanical stirring at 200 r / min until the copolymer is fully dissolved. Control the system temperature at 15 ℃, add 2.28 g of benzyltriethylammonium chloride, stir for 5 min, add 20 g of 30% hydrogen peroxide aqueous solution, stir for 5 min, then add 10.8 mL of 16 mol / L potassium hydroxide aqueous solution, stir for 5 min. Place the three-necked flask in a 24 ℃ oil bath and react for 3~7 h under stirring, then let it stand overnight. Acidify the reaction product, then add 5 times the volume of deionized water. The system separates into layers, with the upper layer being the aqueous phase and the lower layer being the organic phase. Small bubbles continuously rise from the organic phase to the aqueous phase. After the small bubbles completely disappear, collect the organic phase product and place it in a 60 L oil bath. The system was dried in a vacuum oven at ℃ for 24 hours to remove moisture, resulting in a pale yellow viscous liquid AEF with a number-average molecular weight of 2200 g / mol.

[0045] (2) Take 10 g of AEF obtained in step (1) and place it in a three-necked flask. Add 100 mL of acetone to dissolve it. After AEF is completely dissolved, add 0.8 g of silver carbonate, 1.7 g of allyl sulfone and 0.5 g of potassium persulfate to the three-necked flask in sequence. React at 30 °C for 2 h under mechanical stirring. After the reaction is completed, collect the product, wash it with deionized water to settle it 2-3 times, and dry the product under vacuum at 65 °C to constant weight to obtain vinyl-terminated fluororubber.

[0046] Preparation method of epoxy resin dispersion: 4 g boron nitride (particle size of about 1~10 μm) was added to 23 g furfuryl alcohol glycidyl ether and sonicated in an ice water bath for 1 h to obtain a uniformly dispersed boron nitride dispersion. Then, 10 g of epoxy resin E51110 was added and stirred at 500 r / min for 0.5 h to obtain epoxy resin dispersion.

[0047] The conductive silver powder is composed of flake silver powder and spherical silver powder in a weight ratio of 2.5:1.

[0048] The preparation method of carbon nanotube dispersion is as follows: 1g of carbon nanotubes, 0.1g of ultralong carbon nanotubes and 1.0g of dispersant are added to 75g of deionized water and stirred at 500 r / min to completely wet the carbon nanotubes; the dispersant is a mixture of sodium glycocholate, glycerol, dodecyl dimethyl betaine and aminoacetic acid in a weight ratio of 3:1:0.3:0.4; then 1.4g of p-hydroxybenzaldehyde is added, and the dispersion is further carried out using an ultrasonic cell disruptor with an output power of 600 W and an ultrasonic dispersion time of 10 min; finally, the dispersion is centrifuged at 900 r / min for 15 min to obtain the carbon nanotube dispersion.

[0049] Example 2

[0050] The preparation method of heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive is as follows: (1) 30 parts of acrylic resin, 5 parts of carbon nanotube dispersion, 8 parts of epoxy resin dispersion, 3.0 parts of diethylenetriamine, 0.9 parts of 2-ethyl-4-methylimidazole, and 25 parts of acetone are stirred evenly to obtain mixture A; (2) 0.7 parts of p-hydroxyanisole, 65 parts of conductive silver powder (composed of flake silver powder and spherical silver powder in a weight ratio of 3.6:1) and 1.9 parts of coupling agent KH-560 are added to mixture A and stirred evenly to obtain mixture B; (3) Mixture B is degassed under a vacuum degree <-0.095MPa for 10min to obtain heat-resistant, highly dispersible, self-healing, and highly adhesive conductive adhesive;

[0051] The preparation method of acrylate resins is as follows:

[0052] (1) Preparation of core layer emulsion: Add 70 g of water, 18 g of emulsifier A (made by mixing sodium dodecylbenzenesulfonate and AEO-9 at a mass ratio of 2.5:1) and 45 g of methacrylic acid to the reaction vessel, mix and stir evenly, heat to 60 ℃, stir for 60 min, then add monomer A, 14.5 g of DOPO and 6.12 g of maleic anhydride, stir for 40 min; heat to 65 ℃ and reflux water, continue to heat to 90 ℃, add 1.5 g of potassium persulfate initiator (dissolved in 10 g of water) dropwise, add for 1.0 h, react for 2 h to obtain core layer emulsion;

[0053] (2) Add monomer B and 2 g of potassium persulfate (dissolved in 10 g of water) dropwise to the core emulsion obtained in step (1) over a period of 1.5 h. Keep the mixture at 85 °C and stir for 1.5 h. Then add 8.1 g of diisopropanolamine and 0.32 g of p-toluenesulfonic acid and react at 85 °C for 3 h. Then add 37.6 g of tetrahydroxymethylphosphonic acid and 3.1 g of diethylthiophosphoric acid and stir for 2 h at 80 °C. Then add 3.4 g of zirconium sulfate, 0.24 g of aspartic acid and 0.31 g of 1H-indole-2-carboxamide. Cool the mixture to 40 °C and add 21 g of emulsifier AEO-9 and 3.5 g of softener. React for 60 min. Add ammonia to adjust the pH to 7-8 and distill under reduced pressure until the solid content is 70% to obtain an acrylate resin.

[0054] Monomer A is a mixture of 60 g of ethyl acrylate, 38 g of methyl methacrylate, 7 g of styrene and 3 g of vinyl-terminated fluororubber.

[0055] Monomer B is a mixture of 70 g of methyl methacrylate, 86 g of ethyl acrylate, 5 g of styrene and 3 g of vinyl-terminated fluororubber.

[0056] Preparation method of fabric softener: Add 0.4 g of chloroplatinic acid and 8 g of isopropanol to a four-necked flask, heat to 80 ℃, slowly add 2.2 g of terminal hydrogen silicone oil and 36 g of allyl epoxy polyether dropwise over 1 h, add glacial acetic acid to maintain the pH of the system at 5-6, and react at 100 ℃ for 4 h to obtain intermediate A; continue to add 13 g of polyetheramine D400 and 2.4 g of ethylboric acid to intermediate A, maintain the pH of the system at 5-6, react at 90 ℃ for 5 h, and obtain fabric softener after cooling.

[0057] The preparation method of vinyl-terminated fluororubber is as follows:

[0058] (1) Add 60 g of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer and 600 mL of acetone to a 2 L three-necked flask and let it stand at room temperature for 24 h. Then stir it for 60 min under mechanical stirring at 300 r / min until the copolymer is fully dissolved. Control the system temperature at 15 ℃, add 2.28 g of benzyltriethylammonium chloride, stir for 10 min, add 24 g of 30% hydrogen peroxide aqueous solution, stir for 5 min, then add 10.8 mL of 16 mol / L potassium hydroxide aqueous solution, stir for 5 min. Place the three-necked flask in a 24 ℃ oil bath and react for 7 h under stirring, then let it stand overnight. Acidify the reaction product, then add 5 times the volume of deionized water. The system separates into layers, with the upper layer being the aqueous phase and the lower layer being the organic phase. Small bubbles continuously rise from the organic phase to the aqueous phase. After the small bubbles completely disappear, collect the organic phase product and dry it in a vacuum oven at 60 ℃ for 24 h. h, remove water from the system to obtain a pale yellow viscous liquid AEF with a number average molecular weight of 2200 g / mol;

[0059] (2) Take 10 g of AEF obtained in step (1) and place it in a three-necked flask. Add 100 mL of acetone to dissolve it. After AEF is completely dissolved, add 1.0 g of silver carbonate, 2.1 g of allyl sulfone and 0.8 g of potassium persulfate to the three-necked flask in sequence. React at 65 °C for 4 h under mechanical stirring. After the reaction is completed, collect the product, wash it with deionized water to settle it 3 times, and dry the product under vacuum at 65 °C to constant weight to obtain vinyl-terminated fluororubber.

[0060] Preparation method of epoxy resin dispersion: 6 g boron nitride (particle size of about 1~10 μm) was added to 23 g furfuryl alcohol glycidyl ether and sonicated in an ice water bath for 1.5 h to obtain a uniformly dispersed boron nitride dispersion. Then, 30 g of epoxy resin E511 was added and stirred at 1000 r / min for 1.5 h to obtain epoxy resin dispersion.

[0061] The preparation method of carbon nanotube dispersion is as follows: 1 g of carbon nanotubes, 0.6 g of ultralong carbon nanotubes and 1.6 g of dispersant are added to 75 g of deionized water and stirred at 1200 r / min to completely wet the carbon nanotubes; the dispersant is a mixture of sodium glycocholate, glycerol, dodecyl dimethyl betaine and aminoacetic acid in a weight ratio of 3:1.5:0.5:0.45; then 2.7 g of p-hydroxybenzaldehyde is added, and the dispersion is further carried out using an ultrasonic cell disruptor with an output power of 700 W and an ultrasonic dispersion time of 50 min; finally, the dispersion is centrifuged at 1200 r / min for 30 min to obtain the carbon nanotube dispersion.

[0062] Example 3

[0063] The preparation method of heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive is as follows: (1) 27.5 parts of acrylic resin, 4.5 parts of carbon nanotube dispersion, 6.5 parts of epoxy resin dispersion, 2.8 parts of diethylenetriamine, 0.8 parts of 2-ethyl-4-methylimidazole, and 20.5 parts of acetone are stirred evenly to obtain mixture A; (2) 0.5 parts of antioxidant 264, 58.5 parts of conductive silver powder (flake silver powder and spherical silver powder in a weight ratio of 3.0:1) and 1.15 parts of coupling agent KH792 are added to mixture A and stirred evenly to obtain mixture B; (3) mixture B is degassed for 10 min under a vacuum degree <-0.095MPa to obtain heat-resistant, highly dispersible, self-healing, and highly adhesive conductive adhesive;

[0064] The preparation method of acrylate resins is as follows:

[0065] (1) Preparation of core layer emulsion: Add 55 g of water, 15 g of emulsifier A (made by mixing sodium dodecylbenzenesulfonate and AEO-9 at a mass ratio of 2.5:1) and 32.5 g of methacrylic acid to the reaction vessel, mix and stir evenly, heat to 55 ℃, stir for 50 min, then add monomer A, 14 g of DOPO and 6 g of maleic anhydride, stir for 35 min; heat to 65 ℃ and reflux water, continue to heat to 80 ℃, add 1.25 g of potassium persulfate initiator (dissolved in 12 g of water) dropwise, add over a time of 0.75 h, react for 1.5 h to obtain core layer emulsion;

[0066] (2) Add monomer B and 1.5 g of potassium persulfate (dissolved in 13 g of water) dropwise to the core emulsion obtained in step (1) for 1 h. Keep the mixture at 80 °C and stir for 1 h. Then add 8 g of diisopropanolamine and 0.32 g of p-toluenesulfonic acid and react at 75 °C for 2 h. Then add 37 g of tetrahydroxymethylphosphoric acid and 2.95 g of diethylthiophosphoric acid and stir for 1.5 h at 75 °C. Then add 3.1 g of zirconium sulfate, 0.17 g of aspartic acid and 0.21 g of 1H-indole-2-carboxamide. Cool the mixture to 40 °C and add 17.5 g of emulsifier AEO-9 and 2.8 g of softener. React for 45 min. Add ammonia to adjust the pH to 7-8. Distill under reduced pressure until the solid content is 70% to obtain acrylate resin.

[0067] Monomer A is composed of 46.5 g of ethyl acrylate, 30 g of methyl methacrylate, 6 g of styrene and 2 g of vinyl-terminated fluororubber;

[0068] Monomer B is a mixture of 45 g of methyl methacrylate, 68 g of ethyl acrylate, 4 g of styrene and 2 g of terminal vinyl fluororubber.

[0069] Preparation method of fabric softener: Add 0.3 g of chloroplatinic acid and 7 g of isopropanol to a four-necked flask, heat to 75 ℃, slowly add 2.2 g of terminal hydrogen silicone oil and 30.5 g of allyl epoxy polyether dropwise over 1 h, add glacial acetic acid to maintain the pH of the system at 5-6, and react at 95 ℃ for 3 h to obtain intermediate A; continue to add 12 g of polyetheramine D400 and 1.8 g of ethylboric acid to intermediate A, maintain the pH of the system at 5-6, react at 80 ℃ for 3.5 h, and obtain fabric softener after cooling.

[0070] The preparation method of vinyl-terminated fluororubber is as follows:

[0071] (1) Add 60 g of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer and 550 mL of acetone to a 2 L three-necked flask and let it stand at room temperature for 24 h. Then stir it for 45 min under mechanical stirring at 250 r / min until the copolymer is fully dissolved. Control the system temperature at 15 ℃, add 2.28 g of benzyltriethylammonium chloride and stir for 5 min. Add 22 g of 30% hydrogen peroxide aqueous solution and stir for 5 min. Then add 10.8 mL of 16 mol / L potassium hydroxide aqueous solution and stir for 5 min. Place the three-necked flask in a 24 ℃ oil bath and stir for 5 h. Let it stand overnight. Acidify the reaction product and then add 5 times the volume of deionized water. The system separates into layers, with the upper layer being the aqueous phase and the lower layer being the organic phase. Small bubbles continuously rise from the organic phase to the aqueous phase. After the small bubbles completely disappear, collect the organic phase product and dry it in a vacuum oven at 60 ℃ for 24 hours. h, remove water from the system to obtain a pale yellow viscous liquid AEF with a number-average molecular weight of 2200 g / mol;

[0072] (2) Take 10 g of AEF obtained in step (1) and place it in a three-necked flask. Add 100 mL of acetone to dissolve it. After AEF is completely dissolved, add 0.9 g of silver carbonate, 1.9 g of allyl sulfone and 0.65 g of potassium persulfate to the three-necked flask in sequence. React at 45 °C for 3 h under mechanical stirring. After the reaction is completed, collect the product, wash it with deionized water to settle it 2-3 times, and dry the product under vacuum at 65 °C to constant weight to obtain vinyl-terminated fluororubber.

[0073] Preparation method of epoxy resin dispersion: 5 g boron nitride (particle size of about 1~10 μm) was added to 23 g furfuryl alcohol glycidyl ether and sonicated in an ice water bath for 1 h to obtain a uniformly dispersed boron nitride dispersion. Then, 20 g of epoxy resin E511 was added and stirred at 750 r / min for 1 h to obtain epoxy resin dispersion.

[0074] The preparation method of carbon nanotube dispersion is as follows: 1 g of carbon nanotubes, 0.35 g of ultralong carbon nanotubes and 1.3 g of dispersant are added to 75 g of deionized water and stirred at 850 r / min to completely wet the carbon nanotubes; the dispersant is a mixture of sodium glycocholate, glycerol, dodecyl dimethyl betaine and aminoacetic acid in a weight ratio of 3:1.2:0.4:0.4; then 2.1 g of p-hydroxybenzaldehyde is added, and the dispersion is further carried out using an ultrasonic cell disruptor with an output power of 650 W and an ultrasonic dispersion time of 30 min; finally, the dispersion is centrifuged at 1050 r / min for 20 min to obtain the carbon nanotube dispersion.

[0075] Film preparation: The conductive adhesive is mixed evenly according to the weight formula, vacuum treated and poured into a polytetrafluoroethylene mold to form a film, and then its performance is tested.

[0076] The film shrinkage rate is the percentage ratio obtained by dividing the area of ​​the emulsion when it forms a film at 80 ℃ by the area when it is cooled to room temperature.

[0077] Cone calorimetry was performed according to ISO 5660-1 standard: the sample was cut into 100 mm × 100 mm × 3 mm pieces with a heat flux density of 35 kW / m², and the peak smoke generation rate (pSPR) was measured, with units of m³ / s. 2 / s.

[0078] Volume resistivity: measured using a four-probe resistance tester according to the method in GJB 548C—2021 standard.

[0079] Bending resistance stability: The ratio of the resistance of the conductive film to the original resistance was measured after 200 bending cycles at 60 ℃ and a bending radius of 15 mm.

[0080] Thermal conductivity: The sample was measured using the laser pulse method. The sample size was 10 mm × 10 mm and the thickness was 3 mm.

[0081] Adhesion strength: The conductive adhesive is coated on polyimide to a thickness of 3 mm and tested according to GB / T 2792-2014 (peel strength).

[0082] Aging test: High temperature and high humidity aging is adopted. The resistance change rate is less than 20% after aging for 500 hours at 85 ℃ and 85% RH. The stability is considered to be up to standard.

[0083] Heat resistance of the membrane: The formed film was placed in a muffle furnace under nitrogen protection at 700 °C for 10 s and then removed to measure its mass loss rate and area shrinkage rate.

[0084] Table 1. Properties of heat-resistant, high-adhesion, and high-conductivity acrylic resin films

[0085] Heat resistance (mass loss rate) (%) 6.65 5.89 5.13 8.93 10.25 Heat resistance (area shrinkage rate) (%) 1.75 2.13 3.17 6.16 7.97 Thermal conductivity (W / m·K) 2.32 2.18 2.05 1.99 1.64 Volume resistivity (Ω·cm) <![CDATA[6.35×10 -5 ]]> <![CDATA[8.45×10 -5 ]]> <![CDATA[9.35×10 -5 ]]> <![CDATA[1.32×10 -4 ]]> <![CDATA[9.65×10 -4 ]]> Bending resistance stability 1.22 1.19 1.25 2.36 2.57 High temperature and high humidity aging Meets standards Meets standards Meets standards Substandard Substandard <![CDATA[pSPR smoke generation rate reaches its peak (m 2 / s)]]> 0.062 0.073 0.068 0.089 0.126 Membrane shrinkage rate (%) 1.2 1.5 1.3 2.1 3.1 Peel strength (N / cm) 3.86 3.92 3.95 2.3 2.4

[0086] A comparison was made with Example 3 of Invention Patent CN119875459B (where the acrylate resin was replaced with the acrylate resin of this invention, while other components remained unchanged), and with Example 3 of CN119307200B (using the same adhesive composition) (if the comparative patent has corresponding index tests, the test data from the literature was used; otherwise, the tests were conducted by this invention). Table 1 shows that this invention outperforms the comparative patent in terms of heat resistance, thermal conductivity, volume resistivity, film shrinkage, peel strength, high-temperature and high-humidity aging, and peak smoke generation rate.

[0087] Taking Example 1 as an example, the heat resistance (mass loss rate, %) of the conductive film without zirconium sulfate, aspartic acid, or 1H-indole-2-carboxamide was 7.88, 7.12, and 6.88, respectively. Without hexagonal boron nitride or furfuryl alcohol glycidyl ether, the thermal conductivity was 0.57 W / m·K and 1.98 W / m·K, respectively. Without ultralong carbon nanotubes or p-hydroxybenzaldehyde, the volume resistivity of the obtained conductive film was 8.36 × 10⁻⁶. -4 Ω·cm and 6.65×10 -4 Ω·cm; the volume resistivity of the conductive adhesive obtained by using only flake silver powder or only spherical silver powder is 3.73×10 Ω·cm; -4 Ω·cm and 8.86×10 -4 The carbon nanotube dispersion exhibited a static stability exceeding 72 h. Without a dispersant or p-hydroxybenzaldehyde, precipitation occurred after 10 min of standing and less than 48 h of standing, respectively. Without tetramethylolphosphine sulfate and diethylthiophosphoric acid chloride, the peak pSPR smoke generation rates were 0.132 m² / s and 0.126 m² / s, respectively. Without terminal vinyl fluororubber, the film shrinkage rate was 2.6%, and the bending resistance stability was 1.36. Without a softener, the thermal conductivity was 1.77 W / m·K. Other data not mentioned have been verified according to the advantages described in this invention and will not be elaborated here.

Claims

1. A method for preparing a heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive, characterized in that, The preparation method is as follows: (1) 25-30 parts of acrylate resin, 4-5 parts of carbon nanotube dispersion, 5-8 parts of epoxy resin dispersion, 2.6-3.0 parts of diethylenetriamine, 0.7-0.9 parts of 2-ethyl-4-methylimidazole, and 16-25 parts of acetone are stirred and mixed evenly to obtain mixture A; (2) 0.3-0.7 parts of antioxidant, 52-65 parts of conductive silver powder, and 0.4-1.9 parts of coupling agent are added to mixture A and stirred evenly to obtain mixture B; (3) Mixture B is degassed under a vacuum degree <-0.095MPa for 10 minutes to obtain a heat-resistant, highly dispersible, self-healing, and highly adhesive conductive adhesive. The preparation method of the acrylate resin is as follows: (1) Preparation of core layer emulsion: Add 40-70 g of water, 12-18 g of emulsifier A and 20-45 g of methacrylic acid to the reaction vessel, mix and stir evenly, heat to 50-60 ℃, stir and react for 45-60 min, then add monomer A, 13.4-14.5 g of DOPO and 5.88-6.12 g of maleic anhydride, and react for 30-40 min; heat to 65 ℃ and reflux water, continue to heat to 70-90 ℃, add 1-1.5 g of potassium persulfate initiator dropwise, add over a time of 0.5-1.0 h, and react for 1-2 h to obtain core layer emulsion; (2) Simultaneously add monomer B and initiator potassium persulfate 1-2 g to the core emulsion obtained in step (1) over a period of 1-1.5 h. Maintain the reaction temperature at 75-85 °C with stirring for 1-1.5 h. Then add diisopropanolamine 7.9-8.1 g and p-toluenesulfonic acid 0.32 g, and react at 70-85 °C for 1-3 h. Next, add tetramethylphosphoric acid 36.5-37.6 g and diethylthiophosphoric acid 2.8-3.1 g, and react at 70-80 °C with stirring for 1-2 h. Then add zirconium sulfate 2.8-3.4 g, aspartic acid 0.13-0.24 g, and 1H-indole-2-carboxamide 0.11-0.31 g. Cool to 40 °C, add emulsifier AEO-9 14-21 g and softener 2.1-3.5 g, and react for 30-60 h. min, add ammonia to adjust the pH to 7-8, distill under reduced pressure to 70% solid content to obtain acrylate resin; The monomer A is composed of 33-60 g of ethyl acrylate, 22-38 g of methyl methacrylate, 5-7 g of styrene and 1-3 g of vinyl-terminated fluororubber; The monomer B is composed of 20-70 g of methyl methacrylate, 51-86 g of ethyl acrylate, 3-5 g of styrene and 1-3 g of vinyl-terminated fluororubber. The emulsifier A is a mixture of sodium dodecylbenzenesulfonate and AEO-9 in a weight ratio of 2.5:1; The fabric softener is prepared as follows: 0.2-0.4 g of chloroplatinic acid and 6-8 g of isopropanol are added to a four-necked flask, the temperature is raised to 70-80 °C, and 2.2 g of terminal hydrogen silicone oil and 25-36 g of allyl epoxy polyether are slowly added dropwise over a period of 1 h. Glacial acetic acid is added to maintain the pH of the system at 5-6, and the reaction is carried out at 90-100 °C for 2-4 h to obtain intermediate A. 11-13 g of polyetheramine D400 and 1.3-2.4 g of ethylboric acid are then added to intermediate A, the pH of the system is maintained at 5-6, and the reaction is carried out at 75-90 °C for 2-5 h. After cooling, the fabric softener is obtained. The method for preparing the terminal vinyl fluorine rubber is as follows: (1) Add 60 g of vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer and 500-600 mL of acetone to a 2 L three-necked flask and let it stand at room temperature for 24 h. Then stir it for 30-60 min at 200-300 r / min until the copolymer is fully dissolved. Control the system temperature at 15 ℃, add 2.28 g of benzyltriethylammonium chloride and stir for 5-10 min. Add 20-24 g of 30% hydrogen peroxide aqueous solution and stir for 5 min. Then add 10.8 mL of 16 mol / L potassium hydroxide aqueous solution and stir for 5 min. Place the three-necked flask in a 24 ℃ oil bath and stir for 3-7 h. Stop the reaction and let it stand overnight. Acidify the reaction product and then add 5 times the volume of deionized water. The system separates into layers, with the upper layer being the aqueous phase and the lower layer being the organic phase. Small bubbles continuously rise from the organic phase to the aqueous phase. After the small bubbles completely disappear, collect the organic phase product and place it in a 60 ℃ oil bath. The system was dried in a vacuum oven at ℃ for 24 h to remove moisture, resulting in a pale yellow viscous liquid AEF with a number-average molecular weight of 2200 g / mol. (2) Take 10 g of AEF obtained in step (1) and place it in a three-necked flask. Add 100 mL of acetone to dissolve it. After AEF is completely dissolved, add 0.8~1.0 g of silver carbonate, 1.7~2.1 g of allyl sulfone and 0.5~0.8 g of potassium persulfate to the three-necked flask in sequence. React at 30~65 ℃ for 2~4 h under mechanical stirring. After the reaction is completed, collect the product, wash it with deionized water to settle it 2~3 times, and dry the product under vacuum at 65 ℃ to constant weight to obtain vinyl-terminated fluororubber. The preparation method of the epoxy resin dispersion is as follows: 4-6 g of boron nitride is added to 23 g of furfuryl alcohol glycidyl ether, and ultrasonicated in an ice-water bath for 1-1.5 h to obtain a uniformly dispersed boron nitride dispersion. Then, 110-130 g of epoxy resin E51 is added, and the mixture is stirred at 500-1000 r / min for 0.5-1.5 h to obtain the epoxy resin dispersion. The carbon nanotube dispersion is prepared as follows: 1 g of carbon nanotubes, 0.1-0.6 g of ultralong carbon nanotubes, and 1.0-1.6 g of dispersant are added to 75 g of deionized water and stirred at 500-1200 r / min to completely wet the carbon nanotubes; then 1.4-2.7 g of p-hydroxybenzaldehyde is added, and the dispersion is further carried out using an ultrasonic cell disruptor with an output power of 600-700 W and an ultrasonic dispersion time of 10-50 min; finally, the dispersion is centrifuged at 900-1200 r / min for 15-30 min to obtain the carbon nanotube dispersion.

2. The method for preparing the heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive according to claim 1, characterized in that, The boron nitride has a particle size of 1~10 μm.

3. The method for preparing the heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive according to claim 1, characterized in that, The conductive silver powder is composed of flake silver powder and spherical silver powder in a weight ratio of 2.5:1 to 3.6:

1.

4. The method for preparing the heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive according to claim 1, characterized in that, The dispersant is a mixture of sodium glycocholate, glycerol, dodecyl dimethyl betaine and aminoacetic acid in a weight ratio of 3: 1~1.5: 0.3~0.5: 0.4~0.

45.

5. The method for preparing the heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive according to claim 1, characterized in that, The coupling agent is any one of KH550, KH560, KH792, and KH570, or a mixture of two in any proportion.

6. The method for preparing the heat-resistant, highly adhesive, and highly conductive acrylic resin adhesive according to claim 1, characterized in that, The antioxidant is any one of antioxidant 264 and p-hydroxyanisole, or a mixture of the two in any proportion.