Insulating carbon black composite material and application thereof in electronic device sealant

Abstract

The invention discloses an insulating carbon black composite material and application thereof in an electronic device sealant, belongs to the technical field of carbon black production, and aims to solve the problem that the sealant is poor in heat conduction and insulation performance. The preparation method of the composite material comprises the following steps: pretreating carbon black with nitric acid, reacting with silicon dioxide sol prepared from tetraethoxysilane to form a silicon dioxide coating, and modifying with KH550 to obtain the composite material. The composite material is mixed with a boron nitride-phosphorene composite nanosheet suspension and an organosilicon matrix, and the electronic device sealant is prepared through stirring, ultrasonic dispersion, 120 DEG C pre-curing, 160 DEG C secondary curing and vacuum defoaming. The volume resistivity of the sealant is greater than or equal to 1015 omega.cm, the heat conductivity coefficient of the sealant is greater than or equal to 1.0 W / (m.K), the tensile strength of the sealant is 11MPa, the working temperature of an electronic device can be reduced by 12-18 DEG C, and the sealant has high insulation, high heat conductivity and excellent mechanical properties.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of composite materials, and particularly relates to an insulating carbon black composite material and application thereof in electronic device sealant. BACKGROUND

[0002] In today's era of rapid development of electronic technology, electronic devices are rapidly advancing towards miniaturization, high performance and multi-function. This development trend has brought many new challenges, among which the heat dissipation and insulation of electronic devices are particularly prominent, and have become the key bottleneck restricting the further upgrading of electronic devices.

[0003] With the continuous rise of the integration of electronic devices, such as high-performance computing devices, 5G communication devices, and electronic control systems in electric vehicles, the number of electronic components in a unit volume has increased significantly, resulting in a sharp rise in heat generated by the device during operation. Taking the power device of a 5G base station as an example, its power density when working is several times higher than that of a 4G base station. If the heat cannot be dissipated in time and effectively, the device temperature will rise rapidly, thereby causing performance degradation, reduced stability, and even device damage, which greatly affects the normal operation and service life of the device. Traditional heat dissipation materials, such as metal materials, have relatively high thermal conductivity, but their insulation performance is poor, which can easily cause safety hazards such as short circuits in electronic device sealing scenarios, and cannot meet the dual requirements of heat dissipation and insulation for electronic devices.

[0004] Chinese patent CN104610903A discloses a waterproof electronic device sealant, which aims to improve the waterproof performance of the sealant, but the patent application does not address the problems of insulation and thermal conductivity. The applicant has also searched other relevant patent documents, such as CN104277197A, which discloses an organic silicon-polyurethane pouring sealant and its preparation method, and CN105238320A, which discloses a high-elasticity silane-terminated polypropylene oxide sealant and its preparation method, but neither of them provides technical inspiration for improving the insulation and thermal conductivity of the sealant. SUMMARY

[0005] The present application aims to solve the technical problem of poor material-based thermal conductivity and insulation performance of electronic device sealant, and provides an insulating carbon black composite material and its application in electronic device sealant.

[0006] The object of the present application can be achieved by the following technical solutions: An insulating carbon black composite material is prepared by the following steps: A1, carbon black with a particle size of 20-40 nm is selected, refluxed in a 3 mol / L nitric acid solution at 70℃ for 3 hours, ultrasonically dispersed for 30 minutes, filtered, washed with deionized water until pH=6-7, and vacuum dried at 80℃ for 12 hours to obtain pretreated carbon black; A2, using tetraethyl orthosilicate as a precursor, mixing according to the volume ratio of tetraethyl orthosilicate: ethanol: water = 1:4:1, adjusting the pH to 3.5-4.0 with 0.1 mol / L hydrochloric acid, stirring at 30°C for 60 minutes to form a transparent silica sol; A3, adding the pretreated carbon black to the sol system according to the mass ratio of 1:10, stirring at 50°C for 2 hours, the stirring rate is 1000 rpm, allowing the sol particles to adsorb on the surface of the carbon black and undergo condensation reaction to form a gel coating, the product is centrifuged and washed with ethanol for 3 times to remove free sol, vacuum dried at 60°C for 6 hours, and then heat treated at 200°C in a nitrogen atmosphere for 2 hours to convert the gel layer into a dense silica coating, obtaining the insulating carbon black; A4, dissolving the KH550 silane coupling agent (the addition amount is 1-2% of the mass of the carbon black) in the mixed solvent of ethanol and water (the volume ratio of ethanol: water = 8:2), preparing a dispersion liquid, and then adding the insulating carbon black, stirring at 55°C for 1.5 hours to obtain the insulating carbon black composite material.

[0007] Further, an application of an insulating carbon black composite material in an electronic device sealant, comprising the following steps: adding the insulating carbon black composite material to the silicone matrix, stirring at a speed of 1200 rpm for 1 hour to form a premix, adding a boron nitride-phosphorene composite nanosheet suspension to the premix, starting a 200W ultrasonic disperser, using the cavitation effect generated by high-frequency vibration to destroy the nanosheet agglomerates and assist dispersion for 30 minutes, then increasing the stirring speed to 1800 rpm for 1-2 hours of high-speed stirring to further strengthen the dispersion effect, pre-curing at 120°C for 2 hours to preliminarily crosslink the matrix, secondary curing at 160°C for 1.5 hours to promote the interface bonding of phosphorene with boron nitride and carbon black, obtaining the sealant, and vacuum degassing the sealant for 30 minutes to obtain the electronic device sealant.

[0008] Further, the electronic device sealant comprises the following mass parts of raw materials: 10-15 parts of insulating carbon black composite material, 2-4 parts of boron nitride-phosphorene composite nanosheet suspension, and 80-90 parts of silicone matrix.

[0009] Further, the boron nitride-phosphorene composite nanosheet suspension is prepared by the following steps: T1, boron nitride nanosheets were dispersed in an ethanol-water mixture (volume ratio 7:3), 1-2% of the mass of boron nitride nanosheets of KH560 coupling agent was added, 0.1 mol / L dilute hydrochloric acid was used to adjust the pH of the mixture to 4.5, stirring at 300 rpm under constant temperature of 60℃ for 2 hours, after the reaction was completed, centrifugal separation was carried out at 8000 rpm for 15 min, then washed with anhydrous ethanol for 3 times, and finally dried under vacuum at 50℃ for 12h to obtain modified boron nitride nanosheets; T2, the modified boron nitride nanosheets were dispersed in 0.1 mol / L hydrofluoric acid solution, the dosage ratio of modified boron nitride nanosheets to 0.1 mol / L hydrofluoric acid solution was 0.5-1g:1L, stirring at room temperature for 30 minutes, etching the surface trace oxidation layer to expose active boron atoms, then washing with deionized water to pH 7, vacuum drying at 60℃ for 8 hours to obtain pretreated boron nitride nanosheets; T3, quartz boat 1 was used as the deposition substrate, acetone and ethanol were used for ultrasonic cleaning for 30 minutes, after nitrogen blowing dry, the pretreated boron nitride nanosheets were uniformly spread on the surface of the substrate (thickness ≤50μm), avoiding stacking to affect the uniformity of deposition, 500mg red phosphorus was placed in quartz boat 2, which was placed upstream of the reaction tube, the quartz boat 1 loaded with boron nitride nanosheets was placed in the center of the reaction tube, the valves at both ends of the reaction tube were closed, vacuum was drawn to a pressure ≤10Pa, argon gas (flow rate 100sccm) was introduced, repeated 3 times to completely remove the air in the tube, then the argon flow rate was kept at 50sccm and the hydrogen flow rate was 5sccm, the temperature was raised to 550℃ and kept for 0.5-1.5 hours, after the heat preservation was completed, the heating was turned off, the argon and hydrogen atmosphere (flow rate unchanged) was maintained, and the natural cooling to room temperature was carried out, the quartz boat 1 substrate after reaction was placed in n-hexane and ultrasonic cleaned for 10 minutes at 200W to remove the unreacted red phosphorus particles on the surface, the product was collected by centrifugation, and vacuum dried at 60℃ for 2 hours to obtain boron nitride-phosphorene composite nanosheets; T4, the boron nitride-phosphorene composite nanosheets were dispersed in anhydrous ethanol, ultrasonic cleaning was carried out for 30 minutes at 400W to form a 0.5mg / mL suspension, and a boron nitride-phosphorene composite nanosheet suspension was obtained.

[0010] Further, the organic silicon matrix is prepared by the following steps: Dimethyldichlorosilane and phenyltrichlorosilane were added to the toluene solvent in a molar ratio of 4:1 to form a mixed reaction system, anhydrous aluminum chloride catalyst was added to the system under a nitrogen protective atmosphere, the amount of which was 15% of the mass of phenyltrichlorosilane, the system was stirred at a speed of 300 rpm for 30 min, then the reaction temperature was raised to 60℃, and constant temperature reaction was carried out for 7 hours, after the reaction was completed, the product was washed with 0.1 mol / L dilute hydrochloric acid for 15 min, and then vacuum dried at 110℃ for 8 hours to obtain the organic silicon matrix.

[0011] The beneficial effects of the present application are: (1) The material of the present application breaks through 1.0 W / (m·K) in thermal conductivity by the synergistic dispersion of boron nitride nanosheets and insulating carbon black, which is more than 300% higher than that of pure organic silicone sealant. This contradiction of "high insulation-high thermal conductivity" solves the industry pain point of "good insulation but poor thermal conductivity" of traditional sealing materials, which can reduce the working temperature of electronic devices by 12-18℃.

[0012] (2) A phosphorene transition layer is constructed on the surface of the boron nitride nanosheet by chemical vapor deposition, and the two-dimensional layered structure and semiconductor characteristics of phosphorene are used to form an electronic trap synergistic effect with the modified insulating carbon black in the system: the band gap of phosphorene can capture migrating electrons, while the silica coating of insulating carbon black blocks the conduction path, and the volume resistivity of the composite is increased to more than 10 16 Ω·cm, while retaining the high thermal conductivity of boron nitride nanosheet, and the multi-level electronic capture sites are constructed by the three-phase interface of boron nitride-phosphorene-carbon black, which significantly reduces the dielectric loss performance of the electronic device sealant, and the low dielectric loss of the material can reduce signal attenuation.

[0013] (3) The three-dimensional reinforced network formed by insulating carbon black and boron nitride nanosheet makes the tensile strength of the electronic device sealant increase to 11 MPa, and the hardness also increases significantly, and the sealant has good flexibility and ductility, which can deform without breaking when the electronic device is shaken or slightly deformed, and maintains good sealing effect. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application. Meanwhile, the raw materials, reagents or devices used in the following embodiments are commercially available or can be obtained by known methods, unless otherwise specified.

[0015] Example 1

[0016] Preparation of insulating carbon black composite material: A1, 20 nm carbon black was selected, refluxed in 3 mol / L nitric acid solution at 70℃ for 3 hours, ultrasonically dispersed for 30 minutes, filtered, washed with deionized water to pH=6.0, and vacuum dried at 80℃ for 12 hours to obtain pretreated carbon black; A2, tetraethyl orthosilicate (purchased from Shandong Yuanjin New Material Co., Ltd.) was used as the precursor, mixed according to tetraethyl orthosilicate: ethanol: water = 1:4:1 (volume ratio), adjusted to pH 3.5 with 0.1 mol / L hydrochloric acid, stirred at 30°C for 60 minutes, and a transparent silica sol was formed; A3, the pretreated carbon black was added to the sol system at a mass ratio of 1:10, stirred at 50°C for 2 hours, the stirring rate was 1000 rpm, the sol particles were adsorbed on the surface of the carbon black and underwent condensation reaction, a gel coating was formed, the product was centrifuged, washed with ethanol 3 times to remove free sol, vacuum dried at 60°C for 6 hours, then heat treated at 200°C in a nitrogen atmosphere for 2 hours, the gel layer was converted into a dense silica coating, and insulating carbon black was obtained; A4, the KH550 silane coupling agent (purchased from Shandong Yuanjin New Material Co., Ltd.) was dissolved in a mixed solvent of ethanol and water (volume ratio of ethanol: water = 8:2), and the dispersion liquid was prepared, then the surface modification treatment was carried out on the insulating carbon black, stirred at 55°C for 1.5 hours, and the insulating carbon black composite material was obtained.

[0017] Example 2

[0018] Preparation of insulating carbon black composite material: A1, carbon black with a particle size of 30 nm was selected, refluxed in a 3 mol / L nitric acid solution at 70°C for 3 hours, ultrasonically dispersed for 30 minutes, filtered, washed with deionized water until pH = 6.5, and vacuum dried at 80°C for 12 hours to obtain pretreated carbon black; A2, tetraethyl orthosilicate (purchased from Shandong Yuanjin New Material Co., Ltd.) was used as the precursor, mixed according to tetraethyl orthosilicate: ethanol: water = 1:4:1 (volume ratio), adjusted to pH 3.7 with 0.1 mol / L hydrochloric acid, stirred at 30°C for 60 minutes, and a transparent silica sol was formed; A3, the pretreated carbon black was added to the sol system at a mass ratio of 1:10, stirred at 50°C for 2 hours, the stirring rate was 1000 rpm, the sol particles were adsorbed on the surface of the carbon black and underwent condensation reaction, a gel coating was formed, the product was centrifuged, washed with ethanol 3 times to remove free sol, vacuum dried at 60°C for 6 hours, then heat treated at 200°C in a nitrogen atmosphere for 2 hours, the gel layer was converted into a dense silica coating, and insulating carbon black was obtained; A4, the KH550 silane coupling agent (purchased from Shandong Yuanjin New Material Co., Ltd.) was dissolved in a mixed solvent of ethanol and water (volume ratio of ethanol: water = 8:2), and the dispersion liquid was prepared, then the surface modification treatment was carried out on the insulating carbon black, stirred at 55°C for 1.5 hours, and the insulating carbon black composite material was obtained.

[0019] Example 3

[0020] Preparation of insulating carbon black composite material: A1, select carbon black with particle size of 40 nm, reflux for 3 hours at 70°C with 3 mol / L nitric acid solution, ultrasonic dispersion for 30 minutes, then filter, wash with deionized water until pH=7.0, vacuum drying at 80°C for 12 hours to obtain pretreated carbon black; A2, using tetraethyl orthosilicate (purchased from Shandong Yuanjin New Material Co., Ltd.) as precursor, mixing according to tetraethyl orthosilicate: ethanol: water = 1:4:1 (volume ratio), adjusting pH to 4.0 with 0.1 mol / L hydrochloric acid, stirring at 30°C for 60 minutes to form transparent silica sol; A3, adding pretreated carbon black to the sol system according to 1:10 (mass ratio), stirring at 50°C for 2 hours, stirring rate is 1000 rpm, making sol particles adsorb on the surface of carbon black and occur condensation reaction to form gel coating, the product is centrifuged, then washed with ethanol for 3 times to remove free sol, vacuum drying at 60°C for 6 hours, then heat treatment at 200°C under nitrogen atmosphere for 2 hours to convert gel layer into dense silica coating, obtaining insulating carbon black; A4, dissolving KH550 silane coupling agent (purchased from Shandong Yuanjin New Material Co., Ltd.) (addition amount is 2% of carbon black mass) in ethanol-water mixed solvent (volume ratio of ethanol: water = 8:2), preparing dispersion liquid to modify the surface of insulating carbon black, stirring at 55°C for 1.5 hours, obtaining insulating carbon black composite material.

[0021] Example 4

[0022] Preparation of boron nitride-phosphorene composite nanosheet suspension: T1, dispersing boron nitride nanosheets in ethanol-water mixed solution (volume ratio 7:3), adding KH560 coupling agent with 1% of boron nitride nanosheet mass, adjusting pH of the mixed solution to 4.5 with 0.1 mol / L dilute hydrochloric acid, stirring at 300 rpm under constant temperature condition of 60°C for 2 hours, centrifuging for 15 min at 8000 rpm after reaction, then washing with anhydrous ethanol for 3 times, finally drying at 50°C under vacuum condition for 12h, obtaining modified boron nitride nanosheets; T2, dispersing modified boron nitride nanosheets in 0.1 mol / L hydrofluoric acid solution, the dosage ratio of modified boron nitride nanosheets to 0.1 mol / L hydrofluoric acid solution is 0.5g:1L, stirring at room temperature for 30 minutes, etching surface trace oxidation layer to expose active boron atoms, then washing with deionized water until pH is 7, vacuum drying at 60°C for 8 hours, obtaining pretreated boron nitride nanosheets; T3, take quartz boat 1 as deposition substrate, sequentially clean with acetone and ethanol for 30 minutes by ultrasonic, dry with nitrogen after cleaning, spread the pretreated boron nitride nanosheets uniformly on the surface of the substrate (control the thickness ≤ 50 μm, the thickness is controlled to 40 μm in this embodiment), avoid stacking to affect the deposition uniformity, 500 mg of red phosphorus is placed in quartz boat 2, which is placed upstream of the reaction tube, the quartz boat 1 loaded with boron nitride nanosheets is placed in the center of the reaction tube, close the valves at both ends of the reaction tube, vacuumize to a pressure ≤ 10 Pa (the pressure is controlled to 1 Pa in this embodiment), introduce argon (flow rate 100 sccm), repeat 3 times to completely remove the air in the tube, then the argon flow rate is kept at 50 sccm and the hydrogen flow rate is kept at 5 sccm, heat to 550 ℃ and keep for 0.5 hours, after the heat preservation is completed, close the heating, keep the argon and hydrogen atmosphere (the flow rate is unchanged), naturally cool to room temperature, put the reacted quartz boat 1 substrate into n-hexane and clean for 10 minutes by 200 W ultrasonic, remove the unreacted red phosphorus particles on the surface, centrifugal collect the product, vacuum dry at 60 ℃ for 2 hours, and obtain boron nitride-phosphorene composite nanosheets; T4, disperse the boron nitride-phosphorene composite nanosheets in anhydrous ethanol, form a 0.5 mg / mL suspension by 400 W ultrasonic dispersion for 30 minutes, and obtain a boron nitride-phosphorene composite nanosheet suspension.

[0023] Example 5

[0024] Preparation of boron nitride-phosphorene composite nanosheet suspension: T1, disperse the boron nitride nanosheets in an ethanol-water mixture (volume ratio 7:3), add 1.5% of the mass of the boron nitride nanosheets of KH560 coupling agent, adjust the pH of the mixture to 4.5 by using 0.1 mol / L dilute hydrochloric acid, stir at 300 rpm under constant temperature condition of 60 ℃ for 2 hours, centrifugal separate at 8000 rpm for 15 min after the reaction is completed, then wash with anhydrous ethanol for 3 times, and finally dry under vacuum condition at 50 ℃ for 12 h, and obtain modified boron nitride nanosheets; T2, disperse the modified boron nitride nanosheets in 0.1 mol / L hydrofluoric acid solution, the use amount ratio of the modified boron nitride nanosheets to the 0.1 mol / L hydrofluoric acid solution is 0.75 g:1 L, stir at room temperature for 30 minutes, etch the trace of surface oxidation layer to expose active boron atoms, then wash with deionized water to pH 7, and vacuum dry at 60 ℃ for 8 hours, and obtain pretreated boron nitride nanosheets; T3, using quartz boat 1 as the deposition substrate, sequentially ultrasonic cleaning with acetone and ethanol for 30 minutes, after nitrogen blowing dry, the pretreated boron nitride nanosheets were evenly spread on the surface of the substrate (thickness ≤50 μm, the thickness of this embodiment was controlled to be 45 μm), avoiding stacking to affect the deposition uniformity, 500 mg of red phosphorus was placed in quartz boat 2, which was placed upstream of the reaction tube, and the quartz boat 1 loaded with boron nitride nanosheets was placed in the center of the reaction tube, the valves at both ends of the reaction tube were closed, vacuum was drawn to a pressure ≤10 Pa (in this embodiment, the pressure was controlled to be 1 Pa), argon gas was introduced (flow rate 100 sccm), and the process was repeated 3 times to completely remove the air in the tube. After that, the argon flow rate was kept at 50 sccm and the hydrogen flow rate was 5 sccm, the temperature was raised to 550°C and kept for 1 hour, after the heat preservation was completed, the heating was turned off, the argon and hydrogen atmosphere was maintained (flow rate unchanged), and the system was naturally cooled to room temperature. The quartz boat 1 substrate after reaction was placed in n-hexane and ultrasonically cleaned for 10 minutes at 200W to remove the unreacted red phosphorus particles on the surface, the product was collected by centrifugation, and vacuum dried at 60°C for 2 hours to obtain boron nitride-phosphorene composite nanosheets; T4, the boron nitride-phosphorene composite nanosheets were dispersed in anhydrous ethanol, ultrasonicated at 400W for 30 minutes to form a 0.5mg / mL suspension, and a boron nitride-phosphorene composite nanosheet suspension was obtained.

[0025] Example 6

[0026] Preparation of boron nitride-phosphorene composite nanosheet suspension: T1, the boron nitride nanosheets were dispersed in an ethanol-water mixture (volume ratio 7:3), 2% of the mass of the boron nitride nanosheets of KH560 coupling agent was added, the pH of the mixture was adjusted to 4.5 using 0.1 mol / L dilute hydrochloric acid, and the mixture was stirred at 300 rpm under constant temperature conditions at 60°C for 2 hours. After the reaction was completed, the mixture was centrifuged at 8000 rpm for 15 min, then washed with anhydrous ethanol 3 times, and finally dried under vacuum conditions at 50°C for 12h to obtain modified boron nitride nanosheets; T2, the modified boron nitride nanosheets were dispersed in 0.1 mol / L hydrofluoric acid solution, the use amount ratio of the modified boron nitride nanosheets to the 0.1 mol / L hydrofluoric acid solution was 1g:1L, and the mixture was stirred at room temperature for 30 minutes. The surface was etched to expose active boron atoms, then washed with deionized water to adjust the pH to 7, and vacuum dried at 60°C for 8 hours to obtain pretreated boron nitride nanosheets; T3, quartz boat 1 was used as the deposition substrate, and was sequentially cleaned with acetone and ethanol by ultrasonic for 30 minutes. After nitrogen blowing dry, the pretreated boron nitride nanosheets were uniformly spread on the surface of the substrate (thickness ≤ 50 μm, thickness of this embodiment is 50 μm), and 500 mg of red phosphorus was placed in quartz boat 2 upstream of the reaction tube. The quartz boat 1 loaded with boron nitride nanosheets was placed in the center of the reaction tube. The valves at both ends of the reaction tube were closed, and the pressure was vacuumed to ≤ 10 Pa (the pressure was controlled to 10 Pa in this embodiment). Argon gas (flow rate of 100 sccm) was introduced, and the process was repeated for 3 times to completely remove the air in the tube. Then, the argon flow rate was maintained at 50 sccm, and the hydrogen flow rate was 5 sccm. The temperature was raised to 550 ℃ and maintained for 1.5 hours. After the heat preservation was completed, the heating was turned off, and the argon and hydrogen atmosphere was maintained (flow rate unchanged). The system was naturally cooled to room temperature. The quartz boat 1 substrate after reaction was placed in n-hexane and cleaned by ultrasonic for 10 minutes at 200 W. The unreacted red phosphorus particles on the surface were removed, and the product was collected by centrifugation. The product was vacuum dried at 60 ℃ for 2 hours to obtain boron nitride-phosphorene composite nanosheets. T4, the boron nitride-phosphorene composite nanosheets were dispersed in anhydrous ethanol, and a 0.5 mg / mL suspension was formed by ultrasonic at 400 W for 30 minutes to obtain a boron nitride-phosphorene composite nanosheet suspension.

[0027] Example 7

[0028] Preparation of silicone matrix: Dimethyldichlorosilane and phenyltrichlorosilane were added to the toluene solvent in a molar ratio of 4:1 to form a mixed reaction system. Anhydrous aluminum chloride catalyst was added to the system under a nitrogen protective atmosphere, and the amount of catalyst was 15% of the mass of phenyltrichlorosilane. The system was stirred at a speed of 300 rpm for 30 min. Then the reaction temperature was raised to 60 ℃, and the constant temperature reaction was carried out for 7 hours. After the reaction was completed, the product was washed with 0.1 mol / L dilute hydrochloric acid for 15 min, and then vacuum dried at 110 ℃ for 8 hours to obtain the silicone matrix.

[0029] Example 8

[0030] The application of the insulating carbon black composite material in the electronic device sealant includes the following steps: Firstly, the electronic device sealant includes the following mass parts of raw materials: 10 parts of the insulating carbon black composite material prepared in Example 1, 2 parts of the boron nitride-phosphorene composite nanosheet suspension prepared in Example 4, and 80 parts of the silicone resin prepared in Example 7. Then, the electronic device sealant is prepared by the following steps: The insulating carbon black composite material prepared in Example 1 was added to the silicone resin prepared in Example 7, stirred at a speed of 1200 rpm for 1 hour to form a premix, and the boron nitride-phosphorene composite nanosheet suspension prepared in Example 4 was added to the premix. A 200 W ultrasonic disperser was started, and the cavitation effect generated by high-frequency vibration was used to break the nanosheet agglomerates and assist dispersion for 30 minutes. Then, the stirring speed was increased to 1800 rpm, and high-speed stirring was performed for 1 hour to further strengthen the dispersion effect. The mixture was pre-cured at 120°C for 2 hours to preliminarily crosslink the matrix, and then secondarily cured at 160°C for 1.5 hours to promote the interfacial bonding of phosphorene with boron nitride and carbon black. A gum was obtained, which was vacuum degassed for 30 minutes to obtain an electronic device sealant.

[0031] Example 9

[0032] The application of the insulating carbon black composite material in electronic device sealant includes the following steps: First, the electronic device sealant includes the following mass parts of raw materials: 12 parts of the insulating carbon black composite material of Example 2, 3 parts of the boron nitride-phosphorene composite nanosheet suspension of Example 5, and 85 parts of the silicone resin prepared in Example 7. Then, the electronic device sealant is prepared by the following steps: The insulating carbon black composite material of Example 2 was added to the silicone resin prepared in Example 7, stirred at a speed of 1200 rpm for 1 hour to form a premix, and the boron nitride-phosphorene composite nanosheet suspension prepared in Example 5 was added to the premix. A 200 W ultrasonic disperser was started, and the cavitation effect generated by high-frequency vibration was used to break the nanosheet agglomerates and assist dispersion for 30 minutes. Then, the stirring speed was increased to 1800 rpm, and high-speed stirring was performed for 1.5 hours to further strengthen the dispersion effect. The mixture was pre-cured at 120°C for 2 hours to preliminarily crosslink the matrix, and then secondarily cured at 160°C for 1.5 hours to promote the interfacial bonding of phosphorene with boron nitride and carbon black. A gum was obtained, which was vacuum degassed for 30 minutes to obtain an electronic device sealant.

[0033] Example 10

[0034] The application of the insulating carbon black composite material in electronic device sealant includes the following steps: First, the electronic device sealant includes the following mass parts of raw materials: 15 parts of the insulating carbon black composite material of Example 3, 4 parts of the boron nitride-phosphorene composite nanosheet suspension of Example 6, and 90 parts of the silicone resin prepared in Example 7. Then, the electronic device sealant is prepared by the following steps: The insulating carbon black composite material prepared in Example 3 was added to the silicone resin prepared in Example 7, stirred at a speed of 1200 rpm for 1 hour to form a premix, and then the boron nitride-phosphorene composite nanosheet suspension prepared in Example 6 was added. A 200W ultrasonic disperser was started, and the cavitation effect generated by high-frequency vibration was used to break the nanosheet agglomerates and assist dispersion for 30 minutes. Then, the stirring speed was increased to 1800 rpm, and high-speed stirring was performed for 2 hours to further strengthen the dispersion effect. The mixture was pre-cured at 120°C for 2 hours to preliminarily crosslink the matrix, and then secondarily cured at 160°C for 1.5 hours to promote the interfacial bonding of phosphorene with boron nitride and carbon black. A sealant for electronic devices was obtained, and the sealant was vacuum degassed for 30 minutes to obtain an electronic device sealant.

[0035] Comparative Example 1 Comparative Example 1 differs from Example 9 in that the insulating carbon black composite material prepared in Example 2 in Example 9 is replaced by the raw material carbon black (carbon black with a particle size of 30 nm) in A1 in Example 2. The remaining raw materials and steps are the same as in Example 9, and finally an electronic device sealant is obtained.

[0036] Comparative Example 2 Comparative Example 2 differs from Example 9 in that the boron nitride-phosphorene composite nanosheet suspension is removed, and finally an electronic device sealant is obtained. The specific steps are as follows: The insulating carbon black composite material prepared in Example 2 was added to the silicone matrix prepared in Example 7, stirred at a speed of 1200 rpm for 1 hour to form a premix, and then the stirring speed was increased to 1800 rpm, and high-speed stirring was performed for 1.5 hours to further strengthen the dispersion effect. The mixture was pre-cured at 120°C for 2 hours to preliminarily crosslink the matrix, and then secondarily cured at 160°C for 1.5 hours to obtain a sealant. The sealant was vacuum degassed for 30 minutes to obtain an electronic device sealant.

[0037] Comparative Example 3 Comparative Example 3 is the silicone resin prepared in Example 7, which is regarded as an electronic device sealant in this comparative example.

[0038] The electronic device sealants prepared in Examples 8-10 and Comparative Examples 1-3 were tested for performance, and the performance test process was as follows. The test results are shown in Table 1: Surface and volume resistances: detected by a ZST-530 volume and surface resistivity tester (produced by Beijing Aviation Times Instrument and Equipment Co., Ltd.) according to the provisions of GB / T31838.2-2019; Thermal conductivity: detected by a XIATECH general thermal conductivity tester TC3100 (produced by Xi'an Xiaxi Electronic Technology Co., Ltd.) according to the provisions of GB / T10297-2015; Tensile strength: refer to the provisions of GB / T6329-1996, using tensile universal testing machine WAW-600E (Jinan Chen Da testing machine manufacturing Co., Ltd.) detection; Hardness: refer to the provisions of GBT2411-2008, using FENIX 200AR Rockwell hardness tester (iron instrument (Shanghai) Co., Ltd. production) detection.

[0039] Dielectric loss: refer to the provisions of IEC60250, using ZJD-A type dielectric constant dielectric loss tester (Beijing Zhonghang times instrument equipment Co., Ltd. production) detection.

[0040] Table 1 test results Item Example 8 Example 9 Example 10 Comparative Example 1 Comparative Example 2 Comparative Example 3 Surface resistance / Ω ≥ 5.13 x 10 15 ]] ≥ 5.25 x 10 15 ]] ≥ 5.20 x 10 15 ]] ≥ 1.55 x 10 6 ]] ≥ 3.80 x 10 14 ]] ≥ 8.26 x 10 5 ]] Volume resistance / Ω-cm ≥ 8.25 x 10 16 ]] ≥ 8.71 x 10 16 ]] ≥ 8.53 x 10 16 ]] ≥ 8.32 x 10 7 ]] ≥ 4.02 x 10 15 ]] ≥ 3.22 x 10 6 ]] Thermal conductivity / (w / (m-k); 25°C) 1.31 1.35 1.33 0.83 0.35 0.31 Tensile strength / MPa ≥11 ≥11 ≥11 ≥6 ≥10 ≥5 Hardness / Shore A ≥74 ≥75 ≥73 ≥55 ≥70 ≥45 Dielectric loss (tan δ) 0.0009 0.0007 0.0008 0.0011 0.0025 0.0030 The surface resistance and volume resistance data of comparative examples 8-10 and comparative examples 1-3 can be obtained: the electronic device sealant prepared by the three groups of example schemes of the application has excellent insulation performance, which meets the insulation requirements.

[0041] The thermal conductivity data of comparative example 9 and comparative example 2 can be obtained: by introducing boron nitride-phosphorene composite nanosheet, the application significantly improves the thermal conductivity of the electronic device sealant.

[0042] The tensile strength and hardness of comparative example 9 and comparative example 1 can be obtained: by modifying the carbon black, the application significantly improves the mechanical properties of the electronic device sealant.

[0043] The dielectric loss data of comparative example 9 and comparative example 2 can be obtained: by introducing boron nitride-phosphorene composite nanosheet, the application significantly reduces the dielectric loss of the electronic device sealant.

[0044] It should be noted that in this paper, such as the term "including, containing" or any other variant is intended to cover non-exclusive containing, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes the elements inherent to such process, method, article or equipment.

[0045] Although the embodiments of the application have been shown and described, it can be understood by those of ordinary skill in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the application, and the scope of the application is defined by the appended claims and their equivalents.

Claims

1. An insulating carbon black composite material, characterized by, Preparation by the following steps: A1, select the particle size of 20-40 nm carbon black, 70 ℃ backflow 3 hours after ultrasonic dispersion 30 minutes by 3 mol / L nitric acid solution, filter, washed with deionized water to pH = 6-7, 80 ℃ vacuum drying 12 hours to get pretreated carbon black; A2, according to the volume ratio of tetraethyl orthosilicate: ethanol: water = 1:4:1 mixed with 0.1 mol / L hydrochloric acid to adjust pH to 3.5-4.0, 30 ℃ stirring 60 minutes, forming sol; A3, the pretreated carbon black and sol according to the mass ratio of 1:10 mixed, 50 ℃ stirring 2 hours, stirring speed 1000 rpm, the product after centrifugal separation, washed with ethanol 3 times, 60 ℃ vacuum drying 6 hours, then in 200 ℃ nitrogen atmosphere for 2 hours, get insulating carbon black; A4, KH550 silane coupling agent according to the solid-liquid ratio 1g:10ml dissolved in ethanol and water mixed solvent, preparation of dispersion after the insulating carbon black is added, 55 ℃ stirring 1.5 hours, again after filtration drying to get insulating carbon black composite material.

2. The insulating carbon black composite material according to claim 1, characterized by The amount of KH550 silane coupling agent added in A4 is 1-2% of the mass of insulating carbon black.

3. The insulating carbon black composite material according to claim 1, characterized by The volume ratio of the mixed solvent ethanol and water in A4 is 8:

2.

4. Use of an insulating carbon black composite material according to any one of claims 1 to 3 in an encapsulant for electronic devices, characterized in that, The application includes the following steps: adding insulating carbon black composite material to silicone matrix, stirring at a speed of 1200 rpm for 1 hour to form a premix, adding boron nitride-phosphorene composite nanosheet suspension to the premix, ultrasonic dispersing for 30 minutes at 200 W, then increasing the stirring speed to 1800 rpm and stirring for 1-2 hours, pre-curing at 120 ℃ for 2 hours, and secondary curing at 160 ℃ for 1.5 hours to obtain a glue, and vacuum degassing the glue for 30 minutes to obtain an electronic device sealant.

5. Use of an insulating carbon black composite material according to claim 4 in encapsulants for electronic devices, characterized in that, The electronic device sealant includes the following mass parts of raw materials: insulating carbon black composite material 10-15 parts, boron nitride-phosphorene composite nanosheet suspension 2-4 parts, and silicone matrix 80-90 parts.

6. Use of an insulating carbon black composite material according to claim 4 in encapsulants for electronic devices, characterized in that, The boron nitride-phosphorene composite nanosheet suspension is prepared by the following steps: T1, disperse boron nitride nanosheets in an ethanol solution with a volume fraction of 70%, add KH560 coupling agent with a mass of 1.5% of the boron nitride nanosheets, adjust the pH of the mixture to 4.5 using 0.1 mol / L dilute hydrochloric acid, stir at a constant temperature of 60 ℃ and a speed of 300 rpm for 2 hours, centrifuge at a speed of 8000 rpm for 15 minutes after the reaction is complete, wash with anhydrous ethanol 3 times, and dry at 50 ℃ under vacuum conditions for 12 hours to obtain modified boron nitride nanosheets; T2, disperse the modified boron nitride nanosheets in a 0.1 mol / L hydrofluoric acid solution, stir at room temperature for 30 minutes, wash with deionized water to pH 7, and vacuum dry at 60 ℃ for 8 hours to obtain pretreated boron nitride nanosheets; T3, using quartz boat 1 as deposition substrate, ultrasonic cleaning with ethanol for 30 minutes, after nitrogen blowing dry, the pretreated boron nitride nanosheet is spread on the surface of the substrate, so that its thickness is ≤50 μm, 500 mg of red phosphorus is placed in quartz boat 2, which is placed upstream of the reaction tube, the quartz boat 1 loaded with boron nitride nanosheet is placed in the center of the reaction tube, the valves at both ends of the reaction tube are closed, vacuum is extracted to a pressure of ≤10 Pa, argon is introduced for 2 minutes to make the flow rate 100 sccm, then the argon flow rate is kept at 50 sccm and the hydrogen flow rate is 5 sccm, the temperature is raised to 550 ℃ and kept for 0.5-1.5 hours, after the heat preservation is completed, the heating is turned off, the argon and hydrogen atmosphere is kept, the flow rate is unchanged, and the natural cooling is carried out to room temperature, then the cooled quartz boat 1 is placed in n-hexane and ultrasonic cleaned for 10 minutes at 200 W, the product is collected by centrifugation, vacuum dried at 60 ℃ for 2 hours, and boron nitride-phosphorene composite nanosheet is obtained; T4, the boron nitride-phosphorene composite nanosheet is dispersed in anhydrous ethanol, ultrasonic cleaning is carried out at 400 W for 30 minutes to form a 0.5 mg / mL suspension, and a boron nitride-phosphorene composite nanosheet suspension is obtained.

7. Use of an insulating carbon black composite material according to claim 4 in encapsulants for electronic devices, characterized in that, The amount ratio of the modified boron nitride nanosheet in T2 to the 0.1 mol / L hydrofluoric acid solution is 0.5-1 g:1 L.

8. Use of an insulating carbon black composite material according to claim 4 in encapsulants for electronic devices, characterized in that, The silicone matrix is prepared by the following steps: Dimethyldichlorosilane, phenyltrichlorosilane and toluene are mixed in a molar ratio of 4:1:20 to form a mixed reaction system, anhydrous aluminum chloride catalyst is added to the system under a nitrogen protective atmosphere, the amount of which is 15% of the mass of phenyltrichlorosilane, the system is stirred at a speed of 300 rpm for 30 minutes, then the reaction temperature is raised to 60 ℃, and constant temperature reaction is carried out for 7 hours, after the reaction is completed, the product is washed with 0.1 mol / L dilute hydrochloric acid for 15 minutes, and then vacuum drying is carried out at 110 ℃ for 8 hours to obtain the silicone matrix.