Electromagnetic shielding sealing material for electronic control unit and preparation method of electromagnetic shielding sealing material

Abstract

The invention relates to the technical field of electromagnetic shielding materials, and discloses an electromagnetic shielding sealing material for an electronic control unit and a preparation method of the electromagnetic shielding sealing material. 40-90 parts of an electromagnetic shielding filler; 5-10 parts of white carbon black; 3-10 parts of a coupling agent; 1-8 parts of a peroxide crosslinking system; 1-5 parts of a softening agent; and 0.5-1.5 parts of a release agent. According to the electromagnetic shielding sealing material provided by the invention, the conductive filler can form a conductive network in the rubber matrix by preferably selecting the conductive filler, so that the consumption of the conductive filler is reduced. The magnetic filler is introduced on the conductive filler by adopting an electroplating method, so that the conductive filler and the magnetic filler cooperate with each other to generate a better electromagnetic shielding effect, and the use amount of the filler is further reduced; the shielding material has excellent conductivity and electromagnetic shielding performance, is suitable for the fields of electric automobiles, aerospace and the like (the shielding material is required to reach the shielding effectiveness of 70 dB or above), and is good in sealing performance and mechanical performance, small in density and low in cost.

Description

Technical Field

[0001] The present invention relates to the field of electromagnetic shielding materials, and in particular to an electromagnetic shielding sealing material for an electronic control unit and a preparation method thereof. Background Art

[0002] With the rapid development of electric vehicles, electronic control units (ECUs) play a vital role in electric vehicles. ECUs are responsible for controlling various electronic systems of the vehicle. Since a large number of electronic components and circuits are integrated inside the ECU, electromagnetic radiation will be generated during operation, and it is also susceptible to external electromagnetic interference, which may affect the normal operation of the ECU and even endanger driving safety. Therefore, an effective electromagnetic shielding sealing material is needed to protect the ECU from electromagnetic interference.

[0003] In order to ensure the normal operation of the ECU, electromagnetic shielding materials such as metal shielding covers and conductive rubber are usually used in its shell or inside. The metal shielding cover can isolate the ECU from the external electromagnetic field, and the conductive rubber can be used to fill the gap between the shielding cover and the ECU. Electromagnetic radiation can easily leak or enter from the gap. The shielding material used to fill the gap between the ECU shielding cover and the ECU is usually a conductive rubber based on silicone rubber. It is mainly composed of the following parts: rubber matrix, conductive filler, metal-plated particles, cross-linking agent and additives. This conductive rubber based on silicone rubber can not only meet the high requirements of the ECU for electromagnetic shielding, but also adapt to the harsh working environment inside the car, such as high and low temperature, vibration, humidity, etc.

[0004] At present, the existing electromagnetic shielding materials have some shortcomings, such as poor shielding effect, poor sealing performance, complex preparation process, high cost, etc. By consulting patent literature, it is known that there are currently many patents related to silicone rubber electromagnetic shielding materials.

[0005] The existing Chinese patent with publication number CN109082123A discloses a graphene-modified electromagnetic shielding silicone rubber material and its preparation method. The patent reports that the graphene-modified silicone rubber uses an anion catalyst, and the conductive filler is one or more of silver-plated glass microbeads, nickel-plated graphite, conductive carbon black, and nano-carbon tubes. The amount used is 100 parts of silicone rubber and 10-150 parts of conductive filler. The electromagnetic shielding effectiveness (SE) of the material in the frequency range of 500-1000Hz can reach 80dB.

[0006] The existing Chinese patent with publication number CN111961347A discloses a highly conductive fluorosilicone rubber composition, preparation method and electromagnetic shielding material. The conductive filler is at least one of nickel powder, nickel-coated graphite powder, silver powder, silver-coated copper, silver-coated aluminum, superconductive carbon black, conductive nano-carbon tubes and conductive graphene, and the amount is 100 parts of silicone rubber and about 150-210 parts of conductive filler, and the shielding effectiveness is higher than 100dB.

[0007] The existing Chinese patent with publication number CN116285359A discloses a high electromagnetic shielding effectiveness silicone rubber composite material and its preparation method and use. The conductive filler adopts at least one of nano carbon materials such as carbon nanotubes, graphene, and graphyne. The metal filler is selected from at least one of silver powder, nickel powder, and silver-coated aluminum powder. The dosage is 100 parts of silicone rubber and about 100 parts of conductive filler. The shielding effectiveness is up to 120dB.

[0008] The existing Chinese patent with publication number CN103665878A discloses a method for preparing shielding silicone rubber. The conductive filler is nickel-plated copper powder, and the preparation amount by electroplating is 100 parts of silicone rubber and 250 parts of conductive filler. The electromagnetic shielding effectiveness of the material is up to 84dB.

[0009] The electromagnetic shielding materials prepared by the above four patented technologies all have high electromagnetic shielding effectiveness (higher than 70dB), but the prepared materials use more conductive fillers or the preparation methods are more complicated, which results in problems such as high cost of the prepared products and difficulty in industrialization. Summary of the invention

[0010] The purpose of the present invention is to provide an electromagnetic shielding sealing material for an electronic control unit and a preparation method thereof, by selecting a conductive filler, the conductive filler can form a conductive network in a rubber matrix, and the amount of conductive filler is reduced. On the other hand, by introducing a magnetic filler on the conductive filler by electroplating, the conductive and magnetic fillers work together to produce a better electromagnetic shielding effect, and the amount of filler is further reduced; so as to solve the problems of high cost and complex preparation process of existing electromagnetic shielding materials.

[0011] The present invention provides the following technical solutions:

[0012] In one aspect, the present invention provides an electromagnetic shielding sealing material for an electronic control unit, comprising the following material components in parts by weight:

[0013]

[0014] In the above embodiment, conductive fillers are preferably used so that the conductive fillers can form a conductive network in the rubber matrix, thereby reducing the amount of conductive fillers used. On the other hand, magnetic fillers are introduced by electroplating on the conductive fillers, so that the conductive and magnetic fillers work together to produce a better electromagnetic shielding effect, further reducing the amount of fillers used.

[0015] According to some embodiments, the silicone rubber includes at least one of methyl vinyl silicone rubber (MVQ), methyl phenyl vinyl silicone rubber (MPVQ), fluorosilicone rubber (FVMQ) and nitrile silicone rubber (NVMQ).

[0016] In the above embodiment, the rubber used is silicone rubber, which has a wide operating temperature range (-50°C-200°C). Silicone rubber includes methyl vinyl silicone rubber (MVQ), methyl phenyl vinyl silicone rubber (MPVQ), fluorosilicone rubber (FVMQ) and nitrile silicone rubber (NVMQ). Methyl vinyl silicone rubber (MVQ) is used in the embodiment. The amount of silicone rubber (by weight) is 100 parts.

[0017] According to some embodiments, the electromagnetic shielding filler includes at least one of nickel-plated carbon nanofibers, nickel-plated carbon fibers, carbon nanofibers, carbon nanotubes, nickel, copper, silver, and carbon black.

[0018] In the above embodiment, nickel-plated carbon nanofibers, nickel-plated carbon fibers and carbon black are selected in the following examples. Electromagnetic shielding fillers are preferably nickel-plated carbon nanofibers, nickel-plated carbon fibers and carbon black. When these three fillers are used in combination, a conductive network can be formed in the rubber, and the rubber has better electromagnetic shielding performance. Based on 100 parts of rubber (by weight), 40-90 parts of fillers, preferably 50-80 parts. The ratio of the three fillers is 2:6:2-4:4:2.

[0019] According to some embodiments, the nickel-plated carbon nanofibers and nickel-plated carbon fibers are prepared by electroplating nickel on carbon nanofibers and carbon fibers, and the electroplating includes the following steps: S11 pretreatment: first use an organic solvent acetone or ethanol for ultrasonic cleaning, and the ultrasonic time is 30-60 minutes to fully remove oil stains; then use an acidic solution, selected from dilute hydrochloric acid treatment, to remove oxides that may exist on the surface; after these treatments, rinse with a large amount of deionized water to ensure that the surface of the carbon nanofibers and carbon fibers is clean and free of residue; S12 prepare the electroplating solution: the formula of the electroplating nickel solution is 300-400g / L of nickel sulfamate, 30-40g / L of nickel chloride, and 30-40g / L of boric acid; S13 electroplating: the pretreated carbon nanofibers and carbon fibers are used as cathodes, and pure nickel plates are used as anodes, and are placed in the electroplating solution; under the action of direct current, nickel ions migrate to the cathode, that is, the carbon nanofibers, and obtain electrons on the cathode surface and are reduced to metallic nickel, thereby plating a nickel layer on the carbon nanofibers; during the electroplating process, the current density is controlled at 1-5A / dm 2 The electroplating time is determined according to the required nickel layer thickness and current density; the nickel-plated carbon nanofibers and nickel-plated carbon fibers are treated with a coupling agent to obtain modified nickel-plated carbon nanofibers and nickel-plated carbon fibers.

[0020] In the above embodiment, in order to overcome the problem that the electromagnetic shielding fillers nickel-plated carbon nanofibers and nickel-plated carbon fibers are difficult to disperse and easy to agglomerate in silicone rubber, the present invention uses coupling agent KH560 to organically treat the electromagnetic shielding fillers, which significantly improves the dispersion uniformity of the electromagnetic shielding fillers in the rubber, and also enhances the bonding force between the electromagnetic shielding fillers and the rubber.

[0021] According to some embodiments, the white carbon black is precipitated white carbon black or gas phase white carbon black, and its specific surface area is 180-220 m2 / g; the white carbon black is treated with a coupling agent to obtain modified white carbon black.

[0022] In the above embodiment, white carbon black has a reinforcing effect on silicone rubber. In order to improve the compatibility between white carbon black and silicone rubber, the coupling agent γ-glycidyloxypropyltrimethoxysilane (KH560) is used to treat white carbon black in the embodiment. The epoxy group in the molecular structure of KH560 has a high reactivity. While reacting with the hydroxyl group on the surface of white carbon black, it can also undergo a cross-linking reaction with the active group in the rubber molecular chain, further enhancing the interface bonding between white carbon black and rubber. The mechanical properties and heat resistance of rubber products can be significantly improved.

[0023] According to some embodiments, the coupling agent includes any one of γ-aminopropyltriethoxysilane (KH-550), vinyltrimethoxysilane (A-171), and γ-glycidoxypropyltrimethoxysilane (KH-560).

[0024] According to some embodiments, the coupling agent treatment process includes the following steps: S21: drying the white carbon black, the nickel-plated carbon nanofiber or the nickel-plated carbon fiber at 110°C for 3 hours to remove moisture adsorbed on the surface thereof; S22: diluting the coupling agent with ethanol to prepare a coupling agent solution with a concentration of 8%; S23: adding the dried white carbon black, nickel-plated carbon nanofiber and nickel-plated carbon fiber to the coupling agent solution, and reacting at 80°C and a stirring speed of 400rpm for 2.5 hours; after the reaction is completed, filtering, washing and drying to obtain modified white carbon black, nickel-plated carbon nanofiber or nickel-plated carbon fiber.

[0025] In the above embodiment, S21 is to remove the moisture adsorbed on the surface, because the moisture will affect the hydrolysis reaction of the coupling agent. If there is too much moisture, the coupling agent may hydrolyze and agglomerate in advance and cannot react well with the white carbon black. The role of the ethanol solvent in S22 is to enable the coupling agent to be better dispersed on the surface of the white carbon black.

[0026] According to some embodiments, the cross-linking system includes a cross-linking agent and a co-cross-linking agent, the cross-linking agent includes any one of diisopropylbenzene peroxide (DCP), 2,5-dimethyl-2,5-di-tert-butylperoxyhexane (DBPH), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane and diethylaminomethyltriethoxysilane; the co-cross-linking agent includes any one of triallyl isocyanurate (TAIC) and trimethylolpropane trimethacrylate (TMPTMA).

[0027] In the above embodiment, the crosslinking agent 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane and the auxiliary crosslinking agent TAIC are selected in the following examples. Based on 100 parts of rubber (by weight), the amount of the peroxide crosslinking system is 1-10 parts, preferably 3-8 parts. The ratio of the crosslinking agent to the auxiliary crosslinking agent is 2:1-5:1.

[0028] According to some embodiments, the softening agent includes any one of paraffin oil, naphthenic oil, and vinyl-terminated polydimethylsiloxane (PDMS-Vi).

[0029] In the above embodiment, the addition of softener is beneficial to the dispersion of shielding filler and white carbon black in silicone rubber, and can also improve the processing performance of silicone rubber. PDMS-Vi is selected as softener in the following examples. Based on 100 parts of rubber (by weight), the softener is 1-5 parts.

[0030] According to some embodiments, the release agent is any one of zinc stearate and barium stearate or a mixture of any two thereof.

[0031] In the above embodiment, the release agent can form an interface coating in the internal mixer, which can make the surface of the agglomerated object easy to release, smooth and clean. In the following examples, zinc stearate is selected. Based on 100 parts of rubber (by weight), the release agent is 0.5-1.5 parts.

[0032] On the other hand, the present invention also provides a method for preparing the electromagnetic shielding sealing material for an electronic control unit, which comprises the following preparation steps:

[0033] S1: Add silicone rubber, electromagnetic shielding filler, white carbon black, softener and release agent to the middle of two rollers of a two-roll mill, and adjust the distance between the two rollers to a suitable distance;

[0034] S2: After the material package in step S1 is rolled, the peroxide cross-linking system is added in sequence, and after the material is eaten, the roller distance is reduced, and the thin pass is passed several times. After the mixing is uniform, the roller distance is increased, and the sheet is removed to obtain a mixed rubber;

[0035] S3: Use a flat plate vulcanizer to prepare the model for vulcanization, put a certain amount of the mixed rubber in step S2 into the mold, and then put the mold between the plates of the flat plate vulcanizer for vulcanization. After the vulcanization is complete, the vulcanization temperature is 200° C., the pressure is 10 MPa, and the time is 20 min.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] Based on the research results of predecessors, the present invention selects nickel-plated carbon nanofibers, nickel-plated carbon fibers and carbon black for compounding, and organically treats the nickel-plated carbon nanofibers and nickel-plated carbon fibers, thereby achieving optimization and improvement in conductive fillers and increasing the conductivity of materials, reducing the content of conductive fillers in the materials, and greatly reducing the cost of materials. The sealing material prepared by the present invention has excellent performance, simple preparation method and low cost. The electromagnetic shielding effectiveness in the range of 50Hz-5GHz is higher than 80dB. It can be used for electromagnetic shielding of electric vehicle ECU and has excellent sealing performance.

[0038] The electromagnetic shielding sealing material of the present invention has good electromagnetic shielding performance in a wide frequency range of 50Hz-5GHz, can effectively shield the electromagnetic radiation generated by the electric vehicle ECU and the electromagnetic interference from the outside, and improves the working stability and reliability of the ECU. The material has excellent sealing performance, can prevent impurities such as dust and moisture from entering the ECU, and protect the ECU from environmental factors. The electromagnetic shielding filler uses conductive and magnetic fillers in combination, and the nano-scale conductive fibers and powder conductive fillers added at the same time can form a conductive network, which reduces the amount of electromagnetic shielding filler used and greatly reduces the material cost. The preparation method is simple and easy to industrialize. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with the embodiments, but it should be understood that the embodiments are only used to exemplify the present invention and do not constitute any limitation on the protection scope of the present invention. All reasonable changes and combinations included in the scope of the invention spirit of the present invention fall within the protection scope of the present invention.

[0040] The present invention is further described below.

[0041] The reagents used in the present invention are from:

[0042] Methyl vinyl silicone rubber (Yichang Xingyue New Materials Co., Ltd., brand 110, vinyl content 0.04%-0.3%, density 0.98g / cm 3 ). Carbon nanofiber (Chengdu Organic Chemistry Co., Ltd., Chinese Academy of Sciences, brand C-25, purity 99wt%, diameter between 150-200nm, length 10-20μm). Nickel powder (Hebei Yirui Alloy Welding Material Co., Ltd. 99.5%, particle size 300 mesh). Carbon black (Shanxi Yongdong Chemical Co., Ltd., brand N550, purity greater than 98%, 40-48nm). The reagents used without indicating the manufacturer are all conventional reagent products that can be purchased commercially.

[0043] The test method used in the performance test of the present invention is as follows:

[0044] Tensile strength: According to GB / T 528-1998 standard, the test result is obtained by using a universal testing machine.

[0045] Compression set - Measured in accordance with GB / T 7759.1-2015 standard using a universal testing machine.

[0046] Shore Hardness - Measured in accordance with GB / T531-2008 standard using a Shore Hardness Tester.

[0047] Density - According to GB / T533-2008 standard, it is tested with a rubber electronic density meter.

[0048] Volume resistivity - Measured in accordance with GB / T 1692-2008 standard using an insulation high resistance tester.

[0049] Electromagnetic shielding effectiveness - GB / T 36763 2018 Appendix A standard was implemented. The shielding effectiveness of the sample was tested using a vector network analyzer (produced by Agilent, USA, model N5230A) and the coaxial transmission reflection method. The test frequency range was 50Hz-5 GHz. The sample was a disc with a thickness of 2.0mm and a diameter of 13.0mm.

[0050] Example 1

[0051] 100 parts of methyl vinyl silicone rubber, 10 parts of nickel-plated carbon nanofibers, 50 parts of nickel-plated carbon nanofibers, 7 parts of white carbon black, 4 parts of vinyl-terminated polydimethylsiloxane (PDMS-Vi), and 1 part of zinc stearate are put into the middle of the two rollers of the double-roll open mill, and the distance between the two rollers is adjusted to a suitable distance; after the rubber material is rolled, 10 parts of carbon black, 3 parts of 2,5-dimethyl-2,5-di-tert-butyl peroxyhexane (DBPH) and 1 part of triallyl isocyanurate (TAIC) are added in sequence, and after the material is eaten, the roller distance is adjusted to a small value, and the thin pass is passed several times. After mixing evenly, the roller distance is increased, and the sheet is removed to obtain a mixed rubber; a flat vulcanizer is used for model vulcanization. The mixed rubber obtained by mixing is placed in a mold, and then the mold is placed between the plates of the flat vulcanizer for vulcanization to obtain an electromagnetic shielding sealing material. The vulcanization temperature is 200°C, the pressure is 10MPa, and the time is 20min. The raw material composition of Example 1 is shown in Table 1. The performances are shown in Table 2.

[0052] Embodiment 2-7

[0053] The raw material compositions of Examples 2-7 are shown in Table 1. The material preparation method is the same as that of Example 1. The various properties are shown in Table 2.

[0054] Table 1 Composition of raw materials of Examples and Comparative Examples

[0055]

[0056] Table 2 Performance of Examples and Comparative Examples

[0057]

[0058]

[0059] From the performance results of Examples 1-7, it can be seen that when the amount of electromagnetic shielding filler is 70 parts, the electromagnetic shielding effectiveness of the electromagnetic shielding sealing material is higher than 80dB, which shows that the material has good electromagnetic shielding performance. Compared with the performance of Example 1, the content of nickel-plated carbon nanofibers in Examples 2-3 gradually increases, that is, as the content of electromagnetic shielding fillers in the material increases, the conductivity and electromagnetic shielding effectiveness of the material are significantly improved. Compared with the performance of Example 1, the content of carbon black in Examples 4-5 gradually increases, but the electromagnetic shielding effectiveness does not increase significantly, which shows that carbon black mainly plays the role of connecting nickel-plated carbon nanofibers in the system. When the amount of carbon black is 10 parts, it can completely connect nickel-plated carbon nanofibers and nickel-plated carbon fibers to form a conductive network channel, and the material achieves good conductivity. Compared with the performance of Example 1, the content of nickel-plated carbon nanofibers in Examples 6-7 gradually increases, and the electromagnetic shielding effectiveness does not increase significantly. This may be due to the increase in the content of nickel-plated carbon nanofibers, and the nickel-plated carbon nanofibers are easy to agglomerate, resulting in uneven dispersion in the material, so the electromagnetic shielding effectiveness of the material is not significantly improved. The material has good tensile strength and low permanent deformation. The permanent deformation of the material can be used as an important reference indicator of the sealing performance of the material. In Examples 1-7, the permanent deformation of the material is less than 30% at room temperature and less than 40% at high temperature, which shows that the material has good sealing performance at high and low temperatures.

[0060] Comparative Examples 1-3

[0061] The total content of electromagnetic shielding fillers in Comparative Examples 1-3 is the same as that in Example 1, except that only two electromagnetic shielding fillers are used in the comparative examples. The material preparation method is the same as that in Example 1. The various properties are shown in Table 2. As can be seen from Table 2, the electrical conductivity and electromagnetic shielding effectiveness of Comparative Examples 1-3 are significantly lower than those of Example 1. This shows that the three conductive fillers of nickel-plated carbon nanofibers, nickel-plated carbon fibers and carbon black have a synergistic effect on the electrical conductivity of the material. The nickel-plated carbon nanofibers and nickel-plated carbon fibers are randomly distributed in the material, connected by carbon black, and finally form a continuous conductive network.

[0062] The above embodiments are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. An electromagnetic shielding sealing material for an electronic control unit, characterized in that: The composition comprises the following materials by weight:

2. The electromagnetic shielding sealing material for an electronic control unit according to claim 1, characterized in that: The silicone rubber includes at least one of methyl vinyl silicone rubber (MVQ), methyl phenyl vinyl silicone rubber (MPVQ), fluorosilicone rubber (FVMQ) and nitrile silicone rubber (NVMQ).

3. The electromagnetic shielding sealing material for an electronic control unit according to claim 1, characterized in that: The electromagnetic shielding filler includes at least one of nickel-plated carbon nanofibers, nickel-plated carbon fibers, carbon nanofibers, carbon nanotubes, nickel, copper, silver and carbon black.

4. The electromagnetic shielding sealing material for an electronic control unit as claimed in claim 3, characterized in that: The nickel-plated carbon nanofibers and nickel-plated carbon fibers are prepared by electroplating nickel on carbon nanofibers and carbon fibers, and the electroplating includes the following steps: S11 pretreatment: first use an organic solvent selected from acetone or ethanol for ultrasonic cleaning, and the ultrasonic time is 30-60 minutes to fully remove oil stains; then use an acidic solution selected from dilute hydrochloric acid to remove oxides that may exist on the surface; after these treatments, rinse with a large amount of deionized water to ensure that the surface of the carbon nanofibers and carbon fibers is clean and free of residue; S12 prepare the electroplating solution: the formula of the electroplating nickel solution is 300-400g / L of nickel sulfamate, 30-40g / L of nickel chloride, and 30-40g / L of boric acid; S13 electroplating: the pretreated carbon nanofibers and carbon fibers are used as cathodes, and pure nickel plates are used as anodes, and are placed in the electroplating solution; under the action of direct current, nickel ions migrate to the cathode, that is, the carbon nanofibers, and obtain electrons on the cathode surface to be reduced to metallic nickel, thereby plating a nickel layer on the carbon nanofibers; during the electroplating process, the current density is controlled at 1-5A / dm 2 The electroplating time is determined according to the required nickel layer thickness and current density; the nickel-plated carbon nanofibers and nickel-plated carbon fibers are treated with a coupling agent to obtain modified nickel-plated carbon nanofibers and nickel-plated carbon fibers.

5. The electromagnetic shielding sealing material for an electronic control unit according to claim 1, characterized in that: The white carbon black is precipitated white carbon black or gas phase white carbon black, and its specific surface area is 180-220m2 / g; the white carbon black is treated with a coupling agent to obtain modified white carbon black.

6. The electromagnetic shielding sealing material for an electronic control unit according to claim 1, characterized in that: The coupling agent includes any one of γ-aminopropyltriethoxysilane (KH-550), vinyltrimethoxysilane (A-171) and γ-glycidyloxypropyltrimethoxysilane (KH-560).

7. The electromagnetic shielding sealing material for an electronic control unit according to any one of claims 4 to 6, characterized in that: The coupling agent treatment process includes the following steps: S21: drying the white carbon black, the nickel-plated carbon nanofiber or the nickel-plated carbon fiber at 110° C. for 3 hours to remove the moisture adsorbed on the surface thereof; S22: diluting the coupling agent with ethanol to prepare a coupling agent solution with a concentration of 8%; S23: adding the dried white carbon black, nickel-plated carbon nanofiber and nickel-plated carbon fiber to the coupling agent solution, and reacting at 80° C. and a stirring speed of 400 rpm for 2.5 hours; after the reaction is completed, filtering, washing and drying to obtain modified white carbon black, nickel-plated carbon nanofiber or nickel-plated carbon fiber.

8. The electromagnetic shielding sealing material for an electronic control unit according to claim 1, characterized in that: The cross-linking system includes a cross-linking agent and a co-cross-linking agent, wherein the cross-linking agent includes any one of diisopropylbenzene peroxide (DCP), 2,5-dimethyl-2,5-di-tert-butylperoxyhexane (DBPH), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane and diethylaminomethyltriethoxysilane; and the co-cross-linking agent includes any one of triallyl isocyanurate (TAIC) and trimethylolpropane trimethacrylate (TMPTMA).

9. The electromagnetic shielding sealing material for an electronic control unit according to claim 1, characterized in that: The softener includes any one of paraffin oil, cyclohexane oil and vinyl-terminated polydimethylsiloxane (PDMS-Vi); and the release agent is any one of zinc stearate and barium stearate or a mixture of the two.

10. A method for preparing an electromagnetic shielding sealing material for an electronic control unit as claimed in any one of claims 1 to 9, characterized in that: The method comprises the following preparation steps: S1: Add silicone rubber, electromagnetic shielding filler, white carbon black, softener and release agent to the middle of two rollers of a two-roll mill, and adjust the distance between the two rollers to a suitable distance; S2: After the material package in step S1 is rolled, the peroxide cross-linking system is added in sequence, and after the material is eaten, the roller distance is reduced, and the thin pass is passed several times. After the mixing is uniform, the roller distance is increased, and the sheet is removed to obtain a mixed rubber; S3: Use a flat plate vulcanizer to prepare the model for vulcanization. Put a certain amount of the mixed rubber in step S2 into the mold, and then put the mold between the plates of the flat plate vulcanizer for vulcanization. After the vulcanization is complete, the vulcanization temperature is 200° C., the pressure is 10 MPa, and the time is 20 min.

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