High-efficiency heat dissipation bus

Abstract

The invention discloses an efficient heat dissipation bus, and belongs to the technical field of buses, the efficient heat dissipation bus comprises a copper-clad aluminum pipe layer, a shielding layer and an insulating layer, the heat dissipation effect of the efficient heat dissipation bus is achieved through modification of the insulating layer, the insulating layer comprises, by weight, 100-200 parts of silicone rubber, 20-30 parts of fumed silica, 20-30 parts of boron nitride and 10-25 parts of tetrapod-like zinc oxide whiskers, and the shielding layer is a copper-clad aluminum pipe layer. 15-30 parts of an interface agent and 1-5 parts of a silane coupling agent; wherein the interface agent is polysiloxane modified by acryloyl perylene and N-acryloyl piperidine. The lamellar boron nitride and tetrapod-like zinc oxide whisker composite filler is blended with the interface agent, so that a three-dimensional heat-conducting path can be formed in the silicon rubber substrate, the interface thermal resistance is reduced, and the interface structure is optimized, thereby greatly improving the heat-conducting property and heat-resisting property of the insulating layer material, and having no negative influence on the mechanical property and insulating property.

Description

Technical Field

[0001] The present invention relates to the technical field of busbars, in particular to a high-efficiency heat dissipation busbar. Background Art

[0002] Busbars are a crucial component of power plants and substations, connecting their generators, transformers, transmission lines, distribution lines, and phase-shifting equipment. Busbar reliability directly impacts the reliability of these systems. Therefore, busbar design is crucial for ensuring the safe operation of power systems, and the heat dissipation performance of the busbar insulation layer is particularly crucial for safe and efficient operation. This is because busbars generate heat due to resistive losses when transmitting current. When the insulation layer poorly dissipates heat, the accumulated heat causes localized temperature increases. When the temperature exceeds the insulation material's tolerance threshold, it accelerates insulation aging and carbonization, and may even cause breakdown and short circuits, resulting in power outages or fire risks. High temperatures also reduce the dielectric strength of the insulation material, exacerbating partial discharge. Furthermore, conductor resistance increases with temperature. When the insulation layer poorly dissipates heat, the busbar temperature rises, resistance increases, and transmission losses further increase, creating a vicious cycle of "heat-loss-heat." Therefore, a busbar with good heat dissipation performance can control the busbar temperature within a reasonable range, ensuring transmission efficiency, maintaining the dielectric stability of the insulation layer, and minimizing discharge damage.

[0003] Silicone rubber has attracted significant attention for busbar insulation due to its excellent insulating properties, lightweight, and low cost. However, pure silicone rubber has a low thermal conductivity and often needs to be mixed with thermally conductive fillers to improve the thermal conductivity of the composite material. Boron nitride, a thermally conductive filler, possesses a layered structure, excellent thermal conductivity, high thermal stability, low thermal expansion coefficient, and high insulation properties, making it highly suitable for applications in extreme environments such as high temperature and high pressure. The introduction of boron nitride within the polymer matrix provides a pathway for phonons to transfer, allowing heat to dissipate rapidly through these channels, preventing significant heat accumulation and extending the service life of the busbar insulation layer. Boron nitride also offers extremely low dielectric loss and excellent insulating properties, but it also has poor dispersion and is prone to agglomeration. The thermal conductivity of the composite material is positively correlated with the filler loading. At low filler loadings, the polymer forms a continuous phase and the filler forms an isolated dispersed phase, forming a "sea-islands" pattern within the composite material, resulting in minimal improvement in the thermal conductivity of the composite material. As the amount of filler added increases, the contact between the fillers and the polymer becomes increasingly close. Once the percolation threshold, at which thermal pathways and networks are formed, is reached, the thermal conductivity of the composite material increases significantly. However, due to differences in the properties of inorganic fillers and the organic polymer matrix, their compatibility is relatively poor. This not only creates thermal resistance at the filler-matrix interface, leading to severe phonon scattering at the interface, but also affects the dispersion of the filler in the matrix, thereby reducing the thermal conductivity of the composite material. Therefore, it is still necessary to modify the filler or composite material to enhance the interfacial coupling between the filler and the polymer, improve the adhesion of the filler to the matrix while reducing defects, and reduce phonon scattering at the interface. Summary of the Invention

[0004] In order to overcome the deficiencies of the above-mentioned prior art, the present invention provides a high-efficiency heat dissipation busbar, the heat dissipation effect of which is achieved by modifying the insulating layer material. By adding polysiloxane modified with acryloylperylene and N-acryloylpiperidine as an interface agent to the silicone rubber and thermally conductive filler composite material of the insulating layer, the interfacial coupling between the filler and the polymer is greatly enhanced, the adhesion of the filler to the substrate is improved, and the thermal conductivity of the insulating layer is improved through the "hydrogen bond-phonon" synergistic heat conduction path.

[0005] The technical solutions for achieving the purpose of the present invention are as follows:

[0006] A high-efficiency heat dissipation busbar includes a copper-clad aluminum tube layer, a shielding layer, and an insulating layer. The insulating layer includes, by weight, 100-200 parts of silicone rubber, 20-30 parts of fumed silica, 20-30 parts of boron nitride, 10-25 parts of tetrapod-shaped zinc oxide whiskers, 15-30 parts of an interface agent, and 1-5 parts of a silane coupling agent. The interface agent has a general structural formula as shown in Formula 1:

[0007]

[0008] Formula 1, wherein m is 2 to 4, n is 10 to 20, and a is 5 to 15.

[0009] Among them, flake boron nitride has a high in-plane thermal conductivity coefficient and can form a two-dimensional thermal conductive path in the silicone rubber matrix, but its out-of-plane thermal conductivity is poor. The four-needle zinc oxide whiskers are distributed in a three-dimensional skeleton form. Their needle-like structure can penetrate the gaps between the boron nitride sheets and act as a thermal bridge to connect adjacent boron nitride sheets, forming a two-dimensional sheet-to-three-dimensional bridge interconnected network, reducing interfacial thermal resistance. At the same time, the three-dimensional structure of the four-needle zinc oxide whiskers prevents the stacking and agglomeration of the boron nitride sheets, forming a dense network with low porosity and improved phonon transmission efficiency.

[0010] Preferably, the mass ratio of the boron nitride to the tetrapod-shaped zinc oxide whiskers is 1:1.

[0011] The interfacial agent is obtained by modifying polysiloxane with acryloylperylene and N-acryloylpiperidine. Polysiloxane has good compatibility with silicone rubber, and the perylene group on the polysiloxane chain segment has conjugated π electrons, which can form π-π stacking with the boron nitride layers, improving the dispersibility of boron nitride and the interfacial compatibility with the silicone rubber substrate. The amide carbonyl group of N-acryloylpiperidine can act as a hydrogen bond acceptor, forming a hydrogen bond network with the hydroxyl groups on the surface of boron nitride, tetrapod-shaped zinc oxide whiskers, and fumed silica, thereby reducing phonon scattering, avoiding the formation of thermal resistance interfaces, and further improving the thermal conductivity of the composite material.

[0012] In a specific embodiment, the shielding layer is any one of a copper foil shielding layer, a copper wire braided shielding layer, an aluminum foil shielding layer, and an aluminum wire braided shielding layer.

[0013] In a specific embodiment, the preparation method of the interface agent is:

[0014] S1. Octamethylcyclotetrasiloxane, 2,4,6,8-tetramethylcyclotetrasiloxane, 1,1,3,3-tetramethyldisiloxane and an initiator were added to a reactor and stirred under N2 atmosphere at room temperature. After the reaction was completed, an excess of anhydrous sodium bicarbonate and an excess of anhydrous sodium sulfate were added; then filtered and rotary evaporated and vacuum dried to obtain a hydrogen-containing polysiloxane;

[0015] S2. Add acryloylperylene, N-acryloylpiperidine, Custer's catalyst and toluene into the reactor in sequence, stir and heat to 70-90°C under N2 atmosphere, dissolve hydrogenated polysiloxane in toluene, and then add it dropwise into the reactor using a constant pressure dropping funnel, heat to 100-120°C and continue the reaction for 18-24 hours. After the reaction is completed, perform rotary evaporation to remove toluene, repeatedly extract with n-hexane to remove excess monomers, perform rotary evaporation and vacuum drying again to obtain an interfacial agent.

[0016] In a specific embodiment, the structural formula of the acryloylperylene is shown in Formula 2, and the structural formula of the N-acryloylpiperidine is shown in Formula 3.

[0017]

[0018] In a specific embodiment, the silicone rubber is methyl vinyl silicone rubber, and the vinyl content of the methyl vinyl silicone rubber is 1 to 5 mol%.

[0019] In a specific embodiment, the aluminum layer in the copper-clad aluminum tube layer is a hollow aluminum tube with a thickness of 6 to 8 mm. The copper layer and the aluminum layer are tightly mechanically bonded, the wall thickness of the copper layer is 2 to 3 mm, the thickness of the shielding layer is 4 to 5 mm, and the thickness of the insulating layer is 5 to 7 mm.

[0020] In a specific embodiment, the diameter of the four-needle zinc oxide whisker is 0.5-5 μm, and the length is 10-50 μm; the average particle size of the fumed silica is 10-50 nm, and the specific surface area is 70-400 m 2 / g.

[0021] In a specific embodiment, the insulating layer further includes, by weight, 0.2 to 2 parts of an antioxidant, 0.5 to 5 parts of a lubricant, 10-30 parts of a flame retardant, and 0.5 to 5 parts of a colorant; the antioxidants are a primary antioxidant and an auxiliary antioxidant in a mass ratio of (1 to 2): 1; the primary antioxidant is a hindered phenol antioxidant, and the auxiliary antioxidant is a phosphite antioxidant; the lubricant is any one or more of low molecular weight esters, metal soaps, stearic acid complex esters, and amides; the flame retardant is one or more of magnesium hydroxide and aluminum hydroxide, and the colorant is one or more of an organic colorant and an inorganic colorant.

[0022] In a specific embodiment, the method for preparing the insulating layer comprises the following steps:

[0023] Silicone rubber, fumed silica, boron nitride, four-needle zinc oxide whiskers, an interfacial agent, and a silane coupling agent are placed in a Hake internal mixer and mixed for a period of time to obtain a premixed rubber material. The premixed rubber material is transferred to a two-roll mill, and additives and a vulcanizing agent are added. The roller spacing is set to 0.35 mm, and cooling water is passed through the rollers. The mixing temperature is lowered to below 40°C, and the mixture is mixed for 20 to 40 minutes to produce a sheet. The insulating layer material is obtained by continuous vulcanization using high-pressure steam, and the insulating layer material is extruded onto the outside of the shielding layer to obtain an insulating layer.

[0024] Beneficial effects

[0025] The present invention provides a high-efficiency heat dissipation busbar, whose heat dissipation performance is achieved through the composite material used in the insulation layer. The insulation layer composite material provided by the present invention forms a three-dimensional heat conduction path by adding boron nitride and tetrapod-shaped zinc oxide whisker composite fillers to silicone rubber, reducing interfacial thermal resistance. In addition, the perylene-based conjugated π electron system in the interfacial agent can form π-π stacking with the boron nitride layers, and the excellent compatibility between the polysiloxane chain segments and the silicone rubber substrate optimizes the interfacial coupling between the boron nitride and the silicone rubber, further reducing the interfacial thermal resistance. The introduction of the amide group of acrylpiperidine can form hydrogen bonds with the hydroxyl groups on the surfaces of boron nitride, fumed silica, and tetrapod-shaped zinc oxide whiskers, filling the interfacial pores and forming a "hydrogen bond-phonon" synergistic heat conduction path. This can improve thermal conductivity uniformity at low filler content, thereby reducing the negative impact of excessive thermal conductive fillers on the mechanical properties of silicone rubber. In addition, the addition of tetrapod-shaped zinc oxide whiskers and fumed silica ensures the strength of the silicone rubber composite material, and the silane coupling agent and interface agent improve the toughness of the silicone rubber composite material, while also improving the heat resistance and weather resistance of the silicone rubber composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the synthesis route of the interfacial agent;

[0027] Figure 2 This is the infrared spectrum of hydrogen-containing polysiloxane and interface agent 1. DETAILED DESCRIPTION

[0028] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0029] In the examples, the experimental methods used are conventional methods unless otherwise specified, and the materials, reagents, etc. used are all commercially available unless otherwise specified.

[0030] The raw materials used in the embodiments and comparative examples are now described as follows:

[0031] Silicone rubber: methyl vinyl silicone rubber, model 112-7, vinyl content 1.8-5 mol%, measured value 3%, purchased from Dongjue Silicone;

[0032] Fumed silica: average particle size is 50nm, specific surface area is 200m 2 / g, model AM-SiO2-021-2, purchased from Zhejiang Yamei Technology;

[0033] Boron nitride: hexagonal boron nitride, model RH-N, average diameter 10 μm, purchased from Dandong Rijin Technology Co., Ltd.

[0034] Tetrapod-shaped zinc oxide whiskers: diameter 0.5-5 μm, length 10-50 μm, purchased from Hangzhou Jikang New Materials Co., Ltd.

[0035] Silane coupling agent: 3-aminopropyltriethoxysilane, KH-550, purchased from Shanghai Macklin;

[0036] Antioxidant: a mixture of antioxidant 1010 (SONOX) and antioxidant 168 (SONOX) in a mass ratio of 1:2, commercially available;

[0037] N-Acryloylpiperidine: Homemade, prepared as follows: Under anhydrous, oxygen-free, and nitrogen-purging conditions, 0.11 mol of piperidine and 0.12 mol of triethylamine were dissolved in 100 mL of dichloromethane. The solution was added dropwise to 7.5 mL of a dichloromethane solution containing acryloyl chloride over 3 hours with stirring, and the solution was maintained at 3-5°C. After the addition was complete, the reaction mixture was stirred at room temperature for 24 hours. The resulting mixture was extracted with dichloromethane and water and purified by column chromatography (n-hexane-ethyl acetate 1:1) to obtain a colorless to light yellow liquid.

[0038]

[0039] Acryloylperylene: Under anhydrous and oxygen-free conditions, dissolve 1 mol of 3-aminoperylene and 3 mol of triethylamine in 100 ml of chloroform. Slowly add 1.05 mol of acryloyl chloride dropwise in an ice-water bath. Stir and react at 60°C for 2 hours. Wash with saturated sodium bicarbonate solution and dry with anhydrous magnesium sulfate. Vacuum dry the concentrate to obtain acryloylperylene.

[0040]

[0041] Lubricant: zinc stearate, commercially available;

[0042] Interface agent 1: Homemade, the preparation method is as follows: add 0.2 mol of octamethylcyclotetrasiloxane, 1.6 mol of 2,4,6,8-tetramethylcyclotetrasiloxane, 0.1 mol of 1,1,3,3-tetramethyldisiloxane and 0.3 wt% of the initiator CF3SO3H accounting for the total amount of the reactants into the reactor, and stir the reaction for 24 hours under N2 atmosphere and 25 ° C. After the reaction is completed, add an excess of anhydrous sodium bicarbonate and stir for 1 hour, then add an excess of anhydrous sodium sulfate and stir for 1 hour; then, filter the mixture and rotary evaporate to obtain a concentrated solution; finally, vacuum dry the concentrated solution for 6 hours to obtain a colorless, transparent liquid hydrogen-containing polysiloxane with a yield of 78.6%. And through 1The integral calculation of H-NMR showed that the number of structural units m in hydrogen-containing polysiloxane was 3 and n was 16; the viscosity was measured by rotational rheometer and was 0.03 Pa·s;

[0043] 1 mol of acryloylperylene, 1.72 mol of N-acryloylpiperidine, 5 ppm of Custer's catalyst and 144 ml of toluene were added to the reactor in sequence, stirred for 15 min under N2 atmosphere, and heated to 80 °C at the same time. 0.1 mol of hydrogen-containing polysiloxane was dissolved in 144 ml of toluene and then added dropwise to the reactor using a constant pressure dropping funnel. The addition was completed within 90 min. The entire reaction was then heated to 100 °C and the reaction was continued for 18 to 24 h. After the reaction was completed, rotary evaporation was performed to remove toluene, and then repeated extraction with n-hexane was performed to remove excess monomers. Rotary evaporation and vacuum drying were performed again to finally obtain the interface agent 1. The synthesis route is as follows: Figure 1 The yield is 91.0% and the viscosity is 9.2 Pa·s. The hydrogen-containing polysiloxane and the interface agent 1 were tested by FT-IR using Nicoletis 50 Fourier transform infrared spectrometer (USA) with a resolution of 4 cm -1 , scanning range is 4000~500cm -1 , the results are as follows Figure 2 As shown. Figure 2 It can be seen that the infrared spectrum of the interface agent 1 is compared with the infrared spectrum of the hydrogen-containing polysiloxane, and the -1 The Si-H characteristic peak at 3267 cm -1 The stretching vibration peak attributed to acryloylperylene-NH appears at 3034 cm -1 The aromatic CH stretching vibration peak attributed to acryloylperylene appears at 1643 cm -1 The C=O stretching vibration peak assigned to N-acryloylpiperidine appears at , proving the successful accession of acryloylperylene and N-acryloylpiperidine.

[0044] Interface agent 2: The preparation method is similar to that of interface agent 1, except that the addition amount of acryloylperylene is 1.72 mol and the addition amount of N-acryloylpiperidine is 1 mol;

[0045] Interface agent 3: The preparation method is different from that of interface agent 1, except that acryloylperylene is not added;

[0046] Interface agent 4: The preparation method is different from that of interface agent 1, except that N-acryloylpiperidine is not added;

[0047] Unless otherwise specified, the components and raw materials used in the examples and comparative examples of the present invention are all commercially available raw materials, and the components and raw materials used in each parallel experiment are all of the same kind.

[0048] Examples and Comparative Examples

[0049] A high-efficiency heat dissipation busbar includes a copper-clad aluminum tube layer, a shielding layer, and an insulating layer. The aluminum layer in the copper-clad aluminum tube layer is a hollow aluminum tube with a thickness of 7 mm. The copper layer and the aluminum layer are tightly mechanically bonded, and the wall thickness of the copper layer is 2 mm. The shielding layer is a copper wire braided shielding layer with a thickness of 4 mm. The insulating layer is a silicone rubber insulating layer with a thickness of 6 mm. The composition and proportion of the silicone rubber insulating layer are shown in Table 1. The preparation method is as follows:

[0050] Silicone rubber, fumed silica, boron nitride, tetrapod-shaped zinc oxide whiskers, an interfacial agent, and a silane coupling agent were placed in a HAAKE Rheomix 600OS mixer (Germany) and mixed for 30 minutes to obtain a premixed rubber compound. The premixed rubber compound was then transferred to a 6-inch two-roll mill (XK-160, Zhanjiang Guangyi Machinery Equipment Co., Ltd., China), where additives and a vulcanizing agent, DBPMH, were added. The roller spacing was set to 0.35 mm, and cooling water was passed through the rollers to reduce the mixing temperature to below 40°C. The mixture was mixed for 20 to 40 minutes, and the sheet was produced. The sheet was continuously vulcanized with 1.5 MPa high-pressure steam for 30 minutes to obtain an insulating layer material. The insulating layer material was then extruded onto the shielding layer to obtain an insulating layer.

[0051] Table 1 Specific composition and ratio of insulating layer materials (parts by weight)

[0052]

[0053] The insulating layer materials prepared in the examples and comparative examples were subjected to the following performance tests, and the results are shown in Table 2.

[0054] 1. Bending strength: The bending strength of the specimen is tested in accordance with GB / T 9341-2008 "Determination of flexural properties of plastics" for insulating layer materials. The specimen size is 80mm×10mm×4mm.

[0055] 2. Elongation at break: According to the national standard GB / T 528-2009 "Determination of tensile stress and strain properties of vulcanized rubber or thermoplastic rubber", the insulation layer material is tested. The insulation layer material is cut into dumbbell shape as required and tested using a SANS electronic tensile testing machine.

[0056] 3. Thermal conductivity: The thermal conductivity test of the sample is carried out in accordance with GB / T 10297-2015 "Determination of thermal conductivity of non-metallic solid materials - Hot wire method" for testing the insulation layer material. The sample size is 10mm×10mm×2mm.

[0057] 4. Electrical insulation properties: The volume resistivity test of the sample is carried out in accordance with GB / T 31838.2-2019 "Dielectric and resistive properties of solid insulating materials - Part 2: Resistance characteristics".

[0058] 5. Heat resistance: The test was conducted in accordance with the national standard "GB / T 6553-2003 Test method for assessing the resistance of electrical insulating materials to tracking and erosion for use in harsh environmental conditions". A voltage of 4.5kV was applied across the insulating material while a dirty liquid was dripped. The time required for the sample to burn through was tested. The longer the burn-through time, the better the heat resistance.

[0059] Table 2 Performance test results of the embodiments and comparative examples

[0060]

[0061]

[0062] It can be seen from the performance of the embodiments and comparative examples that the silicone rubber composite obtained in the embodiments has better thermal conductivity and heat resistance, and the mechanical properties and insulation properties do not decrease significantly, so the prepared busbar has good heat dissipation effect and can effectively extend the service life of the cable.

[0063] In Comparative Example 1, no acryloylperylene was added to the modified interface agent, and the interface coupling between the thermal conductive filler such as boron nitride and the silicone rubber substrate was poor, and its thermal conductivity was significantly lower than that of Example 3.

[0064] In Comparative Example 2, N-acryloylpiperidine was not added to the modified interface agent. When the number of perylene groups was too large, they were easily stacked to form conductive paths, affecting the insulation performance of the composite material.

[0065] Comparative Example 3 does not add tetrapod-shaped zinc oxide whiskers, and the dispersibility of boron nitride is not as good as that of Example 3.

[0066] Comparative Examples 4 and 5 did not add silane coupling agent and interface agent respectively, and their interface effect was poor and the filler dispersion performance was poor. When the total amount of filler did not reach the percolation threshold, the thermal conductivity of the material was not significantly improved.

[0067] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A high-efficiency heat dissipation busbar, characterized in that: The invention comprises a copper-clad aluminum tube layer, a shielding layer and an insulating layer. The insulating layer comprises, by weight, 100 to 200 parts of silicone rubber, 20 to 30 parts of fumed silica, 20 to 30 parts of boron nitride, 10 to 25 parts of tetrapod-shaped zinc oxide whiskers, 15 to 30 parts of an interface agent, and 1 to 5 parts of a silane coupling agent. The interface agent has a general structural formula as shown in Formula 1: Formula 1, wherein m is 2 to 4, n is 10 to 20, and a is 5 to 15.

2. The high-efficiency heat dissipation busbar according to claim 1, characterized in that: The shielding layer is any one of a copper foil shielding layer, a copper wire braided shielding layer, an aluminum foil shielding layer, and an aluminum wire braided shielding layer.

3. The high-efficiency heat dissipation busbar according to claim 1, characterized in that: The preparation method of the interface agent is: S1. Octamethylcyclotetrasiloxane, 2,4,6,8-tetramethylcyclotetrasiloxane, 1,1,3,3-tetramethyldisiloxane and an initiator were added to a reactor and stirred under N2 atmosphere at room temperature. After the reaction was completed, an excess of anhydrous sodium bicarbonate and an excess of anhydrous sodium sulfate were added; then filtered and rotary evaporated and vacuum dried to obtain a hydrogen-containing polysiloxane; S2. Add acryloylperylene, N-acryloylpiperidine, Custer's catalyst and toluene into the reactor in sequence, stir and heat to 70-90°C under N2 atmosphere, dissolve hydrogenated polysiloxane in toluene, and then add it dropwise into the reactor using a constant pressure dropping funnel, heat to 100-120°C and continue the reaction for 18-24 hours. After the reaction is completed, perform rotary evaporation to remove toluene, repeatedly extract with n-hexane to remove excess monomers, perform rotary evaporation and vacuum drying again to obtain an interfacial agent.

4. The high-efficiency heat dissipation busbar according to claim 3, characterized in that: The structural formula of the acryloylperylene is shown in Formula 2, and the general structural formula of the N-acryloylpiperidine is shown in Formula 3.

5. The high-efficiency heat dissipation busbar according to claim 1, characterized in that: The silicone rubber is methyl vinyl silicone rubber, and the vinyl content of the methyl vinyl silicone rubber is 1 to 5 mol%.

6. The high-efficiency heat dissipation busbar according to claim 1, characterized in that: The aluminum layer in the copper-clad aluminum tube layer is a hollow aluminum tube with a thickness of 6 to 8 mm. The copper layer and the aluminum layer are tightly mechanically bonded. The wall thickness of the copper layer is 2 to 3 mm. The thickness of the shielding layer is 4 to 5 mm. The thickness of the insulating layer is 5 to 7 mm.

7. The high-efficiency heat dissipation busbar according to claim 1, characterized in that: The diameter of the four-needle zinc oxide whisker is 0.5-5 μm, and the length is 10-50 μm; the average particle size of the fumed silica is 10-50 nm, and the specific surface area is 70-400 m 2 / g.

8. The high-efficiency heat dissipation busbar according to claim 1, characterized in that: The insulating layer further includes, by weight, 0.2 to 2 parts of an antioxidant, 0.5 to 5 parts of a lubricant, 10-30 parts of a flame retardant, and 0.5 to 5 parts of a colorant; the antioxidants are a primary antioxidant and an auxiliary antioxidant in a mass ratio of (1 to 2):1; the primary antioxidant is a hindered phenol antioxidant, and the auxiliary antioxidant is a phosphite antioxidant; the lubricant is any one or more of low molecular weight esters, metal soaps, stearic acid complex esters, and amides; the flame retardant is one or more of magnesium hydroxide and aluminum hydroxide, and the colorant is one or more of an organic colorant and an inorganic colorant.

9. The high-efficiency heat dissipation busbar according to any one of claims 1 to 8, characterized in that: The method for preparing the insulating layer comprises the following steps: Silicone rubber, fumed silica, boron nitride, four-needle zinc oxide whiskers, an interfacial agent, and a silane coupling agent are placed in a Hake internal mixer and mixed for a period of time to obtain a premixed rubber material. The premixed rubber material is transferred to a two-roll mill, and additives and a vulcanizing agent are added. The roller spacing is set to 0.35 mm, and cooling water is passed through the rollers. The mixing temperature is lowered to below 40°C, and the mixture is mixed for 20 to 40 minutes to produce a sheet. The insulating layer material is obtained by continuous vulcanization using high-pressure steam, and the insulating layer material is extruded onto the outside of the shielding layer to obtain an insulating layer.

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