An electromagnetic interference resistant radiation resistant power cable and method of making the same

Abstract

This invention relates to the field of power cable technology and discloses an electromagnetic interference-resistant and radiation-resistant power cable and its preparation method. The cable includes a conductor core and an insulating shielding layer; the insulating shielding layer is made of EPDM rubber, cerium-modified epoxy / carbon nanotube conductive paste, zinc oxide, stearic acid, dicumyl peroxide, and triallyl isocyanurate. The conductive paste is prepared by liquid-phase dispersion and in-situ chemical grafting reaction of multi-walled carbon nanotubes, tannic acid, cerium salt, and epoxidized soybean oil. This invention constructs a cerium-containing organic coating layer on the surface of carbon nanotubes through the coordination effect of tannic acid and cerium ions and the in-situ grafting of epoxidized soybean oil, improving the dispersibility and interfacial bonding of the filler in the rubber matrix. This structure not only reduces the conductivity percolation threshold and improves the electromagnetic shielding effectiveness, but also utilizes the free radical scavenging ability of the cerium-tannic acid complex to block radiation aging, significantly improving the radiation resistance and service life of the cable.

Description

Technical Field

[0001] This invention relates to the field of power cable technology, specifically to an electromagnetic interference-resistant and radiation-resistant power cable and its manufacturing method. Background Technology

[0002] In specialized applications such as nuclear power plants and aerospace, power transmission systems need to maintain long-term stable operation under conditions of high-energy radiation and complex electromagnetic interference. Ethylene propylene diene monomer (EPDM) rubber, due to its saturated molecular backbone structure, possesses excellent heat resistance and chemical stability, and is often used as the insulation or sheathing substrate for such cables. To ensure the integrity of signal and power transmission, a shielding layer is typically placed outside the insulation layer to suppress electromagnetic interference, which requires the rubber material to have good electrical conductivity.

[0003] Currently, the main method for imparting electromagnetic shielding function to EPDM rubber is by filling it with conductive agents such as carbon black and carbon nanotubes. Although carbon nanotubes have excellent conductivity, their large specific surface area and strong van der Waals forces make them prone to entanglement and aggregation in the rubber matrix. In existing technologies, to achieve the required shielding effectiveness, it is often necessary to increase the amount of conductive filler. However, this leads to a significant increase in the Mooney viscosity of the rubber compound, increasing the difficulty of extrusion processing. At the same time, it will destroy the continuous phase structure of the rubber matrix, resulting in a significant decrease in mechanical properties such as tensile strength and elongation at break, making it difficult to balance processing rheology and physical and mechanical properties.

[0004] Furthermore, under high-energy radiation environments, polymer materials are prone to molecular chain breakage or oxidative cross-linking reactions, leading to material embrittlement and insulation failure. Existing conductive EPDM rubber composites mostly employ simple physical blending processes, resulting in weak interfacial bonding between inorganic fillers and the organic matrix. This interfacial defect not only fails to prevent radiation from penetrating deep into the material but also lacks an effective free radical scavenging mechanism to inhibit radiation-induced aging degradation. Therefore, achieving uniform dispersion of conductive fillers and imparting excellent radiation aging resistance to the material while ensuring high electromagnetic shielding effectiveness remains a major technical challenge in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an electromagnetic interference-resistant and radiation-resistant power cable and its preparation method. It solves the problems of existing EPDM rubber composite materials, which are difficult to simultaneously achieve high electromagnetic shielding effectiveness and excellent mechanical properties, difficult dispersion of high-filler conductive fillers leading to deterioration of processing performance, and easy oxidation degradation and short service life under radiation environment.

[0006] To achieve the above objectives, the present invention provides an electromagnetic interference-resistant and radiation-resistant power cable, employing the following technical solution: An electromagnetic interference-resistant and radiation-resistant power cable includes a conductor core and an insulating shielding layer covering the conductor core. The insulating shielding layer is made of raw materials comprising the following parts by weight: 100 parts of EPDM rubber; 30.0 to 55.0 parts of cerium-modified epoxy / carbon nanotube conductive paste; 3.0 to 5.0 parts of zinc oxide; 0.5 to 1.0 parts of stearic acid; 2.0 to 3.0 parts of dicumyl peroxide; and 1.0 to 2.0 parts of triallyl isocyanurate. The cerium-modified epoxy / carbon nanotube conductive paste is a composite material prepared by liquid-phase dispersion and in-situ chemical grafting reaction of multi-walled carbon nanotubes, tannic acid, cerium salt, and epoxidized soybean oil.

[0007] By adopting the above technical solution, cerium-modified epoxy / carbon nanotube conductive slurry constructs a stable conductive and radiation-resistant bifunctional network in a EPDM rubber matrix. Its mechanism of action is as follows: Multi-walled carbon nanotubes (MWCs) adsorb tannic acid through non-covalent bonding. The phenolic hydroxyl groups in tannic acid coordinate with cerium ions, forming a cerium-containing organic complex layer on the surface of the carbon nanotubes. Simultaneously, cerium ions act as Lewis acid catalysts, catalyzing the ring-opening grafting reaction between the epoxy groups in epoxidized soybean oil and the phenolic hydroxyl groups in tannic acid. This process chemically bonds long-chain epoxidized soybean oil to the surface of carbon nanotubes, utilizing the steric hindrance effect of the long chains of epoxidized soybean oil to inhibit the re-aggregation of carbon nanotubes. Furthermore, the similar polarity of epoxidized soybean oil to EPDM rubber improves the wettability and dispersibility of the filler in the rubber matrix, thereby reducing the conductivity percolation threshold. In addition, the introduced rare-earth element cerium, in combination with the tannic acid complex, possesses free radical scavenging capabilities, which can block radiation-induced free radical reactions in the rubber molecular chains, delaying the aging and degradation of the material.

[0008] Preferably, the cerium-modified epoxy / carbon nanotube conductive paste is prepared by reacting the following components in parts by weight: 10 parts of multi-walled carbon nanotubes; 1.0 to 3.0 parts of tannic acid; 0.2 to 0.8 parts of cerium salt; and 20 to 40 parts of epoxidized soybean oil.

[0009] By adopting the above technical solution, the ratio of tannic acid to cerium salt is controlled within the above range, which can ensure the formation of a continuous coordination layer on the surface of carbon nanotubes. The amount of epoxidized soybean oil is controlled to balance the grafting rate and plasticizing effect, avoid excessive oil phase from reducing the tensile strength of the insulating shielding layer, and at the same time ensure sufficient grafting density to maintain dispersion stability.

[0010] Preferably, the EPDM rubber is a copolymer with an ethylene content of 65wt% to 75wt% and an ethylene-based norbornene content of 4.5wt% to 9.0wt%; the cerium salt is selected from cerium(III) acetylacetone hydrate or anhydrous cerium(III) chloride.

[0011] By adopting the above technical solution and selecting EPDM rubber with specific ethylene and third monomer contents, it is ensured that the matrix has the ability to be filled with a high amount of filler and a fast peroxide crosslinking rate; cerium acetylacetone or anhydrous cerium chloride has good solubility and high catalytic activity in the reaction system, which is conducive to promoting the ring-opening grafting reaction.

[0012] Secondly, the present invention provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable, which adopts the following technical solution: A method for preparing an electromagnetic interference-resistant and radiation-resistant power cable includes the following steps: S1. Preparation of conductive paste: Multi-walled carbon nanotubes are dispersed in an ethanol aqueous solution, tannic acid and cerium salt are added for adsorption, followed by the addition of epoxidized soybean oil. The ethanol aqueous solution is removed by vacuum distillation under vacuum conditions, and the reaction is carried out at a higher temperature to obtain cerium-modified epoxy / carbon nanotube conductive paste. S2. Mixing: Ethylene propylene diene monomer (EPDM) rubber, zinc oxide, stearic acid and cerium-modified epoxy / carbon nanotube conductive slurry are mixed in an internal mixer to obtain masterbatch. S3. Vulcanization: Add dicumyl peroxide and triallyl isocyanurate to the masterbatch, mix evenly on a two-roll mill, and sheet to obtain unvulcanized rubber compound. S4. Extrusion and vulcanization: The unvulcanized rubber compound is extruded onto the outer layer of the conductor core, and then vulcanized at high temperature and cooled to obtain the final product.

[0013] By adopting the above technical solution, this preparation method uses liquid phase dispersion combined with in-situ phase transfer technology, thus avoiding the agglomeration problem during the drying process. Monodispersity of carbon nanotubes and assembly of tannic acid / cerium salts were achieved in an ethanol-water solution using ultrasound. Subsequently, epoxidized soybean oil was added and vacuum distillation was performed. As ethanol and water evaporated, the high boiling point of the epoxidized soybean oil facilitated the transfer of carbon nanotubes from the polar aqueous phase to the nonpolar oil phase. Throughout this process, the surface of the carbon nanotubes remained coated with the liquid medium, without undergoing a drying and agglomeration process. Finally, a grafting reaction was initiated by heating to fix the dispersion. The resulting slurry can be directly mixed with rubber, achieving uniform dispersion without the need for high-intensity mechanical grinding.

[0014] Preferably, in step S1, the adsorption temperature is 25°C to 40°C; the vacuum degree of the reduced pressure distillation is -0.08MPa to -0.09MPa; the temperature of the heating reaction is 110°C to 140°C; and the reaction time is 1.5 hours to 2.0 hours.

[0015] By adopting the above technical solution, the temperature conditions of 25℃ to 40℃ are conducive to the physical adsorption and coordination equilibrium of tannic acid and cerium ions; controlling the vacuum degree at -0.08MPa to -0.09MPa can achieve stable solvent removal and prevent boiling and carrying away materials; the reaction temperature range of 110℃ to 140℃ is the suitable temperature for cerium ions to catalyze the ring-opening of epoxy, ensuring the reaction rate while preventing the thermal oxidation polymerization of epoxidized soybean oil.

[0016] Preferably, in step S1, the amount of ethanol-water solution used is 30 to 50 times the weight of the multi-walled carbon nanotubes; during the vacuum distillation process, the rotation speed of the shearing and stirring is 800 rpm to 1500 rpm; the concentration of the ethanol-water solution is 95%; and dispersion refers to treatment with an ultrasonic generator with a power of 400W to 800W for 30 to 60 minutes.

[0017] By adopting the above technical solution, the solvent ratio and ultrasonic power ensure the initial dispersion state of carbon nanotubes; high-speed shear stirring provides shear force during the solvent evaporation stage, promoting the carbon nanotubes to overcome the interfacial tension and enter the oil phase.

[0018] Preferably, in step S2, the initial temperature of the internal mixer is set to 65°C to 75°C, and the rotor speed is set to 45 rpm to 55 rpm. The mixing process is as follows: first, add EPDM rubber and plasticize for 90 to 120 seconds, then add zinc oxide and stearic acid and mix for 60 seconds, and finally add cerium-modified epoxy / carbon nanotube conductive slurry and continue mixing for 4 to 5 minutes. When the discharge temperature reaches 130°C to 140°C, discharge the material.

[0019] By adopting the above technical solution and using a segmented feeding process, the rubber matrix is ​​first plasticized to reduce its Mooney viscosity, and then the slurry is added, which is conducive to the penetration of the oily components in the slurry into the rubber molecular chains; the discharge temperature is controlled at 130℃ to 140℃ to ensure the plasticization and dispersion of the material while avoiding early scorching of the rubber compound.

[0020] Preferably, in step S3, the roller temperature of the open mill is 45°C to 55°C, and the roller gap is adjusted to 2mm; the operation of uniform mixing includes wrapping the masterbatch around the rollers, adding dicumyl peroxide and triallyl isocyanurate, making triangular wraps on the left and right sides 5 times each, and passing through the mill 3 times.

[0021] By adopting the above technical solutions, low-temperature mixing combined with triangular wrapping and thin-passing processes, through repeated folding and shearing, ensures that trace amounts of vulcanizing agents and crosslinking aids are evenly distributed in the rubber compound, thus guaranteeing the uniformity of the crosslinking density of the final cable insulation layer.

[0022] Preferably, in step S4, the extrusion is performed using a rubber extruder, with the machine body temperature set to 75°C and the die head temperature set to 95°C; the high-temperature vulcanization temperature is 165°C to 175°C, the vulcanization time is 15 minutes to 25 minutes, and the saturated steam pressure is 1.4 MPa to 1.6 MPa.

[0023] By adopting the above technical solution, the stepped extrusion temperature setting gives the rubber material suitable fluidity and ensures a smooth cable surface; the specific high temperature and high pressure vulcanization conditions promote the decomposition of peroxides and trigger the co-crosslinking of EPDM rubber with the epoxidized soybean oil side chains on the slurry surface, forming a dense three-dimensional network structure.

[0024] This invention provides an electromagnetic interference-resistant and radiation-resistant power cable and its manufacturing method. It has the following beneficial effects: 1. This invention prepares a cerium-modified epoxy / carbon nanotube conductive paste containing tannic acid, cerium salt, and epoxidized soybean oil. Long-chain epoxidized soybean oil is chemically bonded to the surface of multi-walled carbon nanotubes via an in-situ grafting reaction, improving the interfacial compatibility between the carbon nanotubes and the EPDM rubber matrix. This structure promotes uniform dispersion of the conductive filler in the rubber matrix, reduces the conductivity percolation threshold, and allows the cable to achieve high electromagnetic shielding effectiveness with a lower filler content, while maintaining good tensile strength and elongation at break of the insulation layer.

[0025] 2. This invention utilizes a metal-organic complex formed by tannic acid and cerium ions as a free radical scavenger, endowing the insulating material with excellent radiation resistance. This complex can effectively capture and quench free radicals in rubber molecular chains induced by high-energy radiation, blocking the chain transmission of oxidative degradation or excessive cross-linking reactions, thereby significantly improving the retention rate of the physical and mechanical properties of the cable under radiation environment and extending its service life.

[0026] 3. The preparation method of this invention employs a process route combining liquid-phase dispersion and in-situ phase transfer. Utilizing the synergistic effect of solvent evaporation and oil-phase displacement, irreversible agglomeration of the nanofiller during drying is avoided. The conductive slurry prepared by this method exhibits good fluidity and dispersibility, effectively reducing the Mooney viscosity of the compound, improving the extrusion processing performance of the compound, and ensuring a smooth, dense, and defect-free surface for the cable insulation shielding layer. Attached Figure Description

[0027] Figure 1 Figure 1 shows the evolution of the chemical structure and the reaction mechanism of the conductive paste of the present invention. Figure 2(a) is a comparison of the infrared spectra of different samples, and Figure 3(b) is a quantitative comparison of the absorbance ratio and conversion degree of key functional groups calculated based on the spectral data. Figure 2Figure 1 shows the rheological properties of the rubber compound and the evaluation of the filler dispersion quality of the present invention. Figure 2(a) is a scanning curve of the dynamic storage modulus as a function of strain measured by a rubber processing analyzer, and Figure 3(b) is a comparison of Mooney viscosity and Payne effect values ​​of rubber compounds prepared by different processes. Figure 3 Figure (a) is a comparison of the tensile strength and elongation at break of each embodiment and the comparative example, and Figure (b) is a comparison of the volume resistivity and average electromagnetic shielding effectiveness of each embodiment and the comparative example. Figure 4 The above are comparative graphs of the radiation aging resistance performance and life evaluation of the present invention. In Figure (a), the absolute value of the elongation at break changes with the cumulative irradiation dose, and Figure (b) is a graph of the elongation at break retention rate changes with the irradiation dose and the verification of the long-term protection mechanism. Detailed Implementation

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] The main raw materials and reagents used in the following examples and comparative examples have the following sources and specifications. Reagents not specifically mentioned are all commercially available analytical grade or higher grade products.

[0030] The EPDM rubber is an amorphous copolymer with an ethylene content of 65wt%-75wt% and a third monomer, ethylene-bis(norbornene) (ENB) content of 4.5wt%-9.0wt%. The Mooney viscosity (ML(1+4)) is 50-70 at 125℃. CAS No.: 25038-36-2.

[0031] Multi-walled carbon nanotubes have a purity greater than 95%, an outer diameter of 10-20 nm, a length of 10-30 μm, and a specific surface area of ​​150-250 m². 2 / g, ash content less than 0.2wt%, CAS No.: 308068-56-6.

[0032] Tannic acid is gallic acid glucoside, which meets the first-grade industrial standard, with the molecular formula C. 76 H 52 O 46 CAS No.: 1401-55-4.

[0033] The purity of cerium acetylacetone (III) hydrate is greater than 99%, with the chemical formula Ce(C5H7O2)3·xH2O and CAS number 15653-01-7.

[0034] Anhydrous cerium chloride (III) with a purity greater than 99.5%, chemical formula CeCl3, CAS number: 7790-86-5.

[0035] Epoxidized soybean oil has an epoxy value greater than 6.0%, a flash point greater than 280℃, an acid value less than 0.5mgKOH / g, and CAS number: 8013-07-8.

[0036] Dicumyl peroxide (DCP), CAS No. 80-43-3, and triallyl isocyanurate (TAIC), CAS No. 1025-15-6, are both commercially available superior grade products; zinc oxide, stearic acid, and anhydrous ethanol are all commercially available analytical grade products.

[0037] Preparation Example 1: This preparation example provides a method for preparing a cerium-modified epoxy / carbon nanotube conductive paste, including the following steps: (1) In a reactor equipped with a mechanical stirrer, an ultrasonic generator and a condensation recovery device, add 400 parts by weight of 95% ethanol aqueous solution, then add 10 parts by weight of multi-walled carbon nanotubes, turn on the ultrasonic dispersion treatment with a power of 600W for 45 minutes until a uniform black suspension is formed. (2) Add 2.0 parts by weight of tannic acid and 0.5 parts by weight of cerium(III) acetylacetone hydrate to the above suspension in sequence. Control the temperature of the system at 30°C and mechanically stir at 400 rpm for 50 minutes to allow tannic acid and cerium ions to complete adsorption and coordination assembly on the surface of carbon nanotubes. (3) Add 30 parts by weight of epoxidized soybean oil to the reaction system, turn on high-speed shear stirring, set the speed to 1000 rpm, and simultaneously heat the system to 90°C. Start the vacuum pump to keep the vacuum degree in the reactor between -0.08 MPa and -0.09 MPa and carry out vacuum distillation. Continue the operation until no liquid drops fall from the condenser and no bubbles are generated in the reaction system, indicating that the ethanol solvent and water have been completely removed and the carbon nanotubes have completed the transfer from the ethanol phase to the oil phase. (4) The temperature of the material in the reactor is further increased to 130°C and the reaction is carried out at constant temperature for 2 hours under normal pressure. The cerium ion catalyzes the in-situ ring-opening grafting reaction between tannic acid and epoxidized soybean oil. After the reaction is completed, the mixture is naturally cooled to room temperature to obtain black cerium-modified epoxy / carbon nanotube conductive slurry.

[0038] Preparation Example 2: This preparation example provides a method for preparing a cerium-modified epoxy / carbon nanotube conductive paste, including the following steps: (1) Add 300 parts by weight of 95% ethanol aqueous solution to the reactor, then add 10 parts by weight of multi-walled carbon nanotubes, and turn on the ultrasonic dispersion treatment with a power of 400W for 30 minutes to obtain a suspension. (2) Add 1.0 part by weight of tannic acid and 0.2 part by weight of cerium acetylacetonate (III) hydrate to the suspension in sequence, and stir at 300 rpm for 40 minutes at 25°C. (3) Add 20 parts by weight of epoxidized soybean oil, turn on the shear stirring at 800 rpm, heat to 80°C, and carry out vacuum distillation at -0.08 MPa until the solvent is completely evaporated; (4) Heat the system to 110°C, react at a constant temperature for 1.5 hours, and then cool to obtain a conductive paste.

[0039] Preparation Example 3: This preparation example provides a method for preparing a cerium-modified epoxy / carbon nanotube conductive paste, including the following steps: (1) Add 500 parts by weight of 95% ethanol aqueous solution to the reactor, then add 10 parts by weight of multi-walled carbon nanotubes, and turn on the ultrasonic dispersion treatment with a power of 800W for 60 minutes to obtain a suspension. (2) Add 3.0 parts by weight of tannic acid and 0.8 parts by weight of cerium(III) acetylacetone hydrate to the suspension in sequence, and stir at 500 rpm for 60 minutes at 40°C. (3) Add 40 parts by weight of epoxidized soybean oil, turn on the shear stirring at 1500 rpm, heat to 95°C, and carry out vacuum distillation at -0.09 MPa until the solvent is completely evaporated; (4) Heat the system to 140°C, react at a constant temperature for 2 hours, and then cool to obtain a conductive paste.

[0040] Preparation Example 4: This preparation example provides a method for preparing a cerium-modified epoxy / carbon nanotube conductive paste, which differs from Preparation Example 1 only in the type of cerium salt used. The specific steps are as follows: (1) Add 400 parts by weight of 95% ethanol aqueous solution to the reaction vessel, add 10 parts by weight of multi-walled carbon nanotubes, and ultrasonically disperse for 45 minutes; (2) Add 2.0 parts by weight of tannic acid and 0.4 parts by weight of anhydrous cerium(III) chloride to the suspension and stir at 30°C for 50 minutes; (3) Add 30 parts by weight of epoxidized soybean oil and remove the solvent by vacuum distillation at 1000 rpm, 90°C and -0.08 MPa. (4) Heat to 130°C, react at a constant temperature for 2 hours, and then cool to obtain conductive paste.

[0041] Preparation Example 5: This preparation example provides a method for preparing a cerium-modified epoxy / carbon nanotube conductive paste, including the following steps: (1) Add 350 parts by weight of 95% ethanol aqueous solution to the reactor, add 10 parts by weight of multi-walled carbon nanotubes, and ultrasonically disperse for 40 minutes; (2) Add 1.5 parts by weight of tannic acid and 0.3 parts by weight of cerium(III) acetylacetone hydrate to the suspension and stir at 35°C for 45 minutes; (3) Add 25 parts by weight of epoxidized soybean oil and remove the solvent by vacuum distillation at 1200 rpm, 85°C and -0.085 MPa. (4) Heat to 125°C, react at a constant temperature for 100 minutes, and then cool to obtain conductive paste.

[0042] Example 1: This embodiment provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable and its insulating material, including the following steps: (1) Mixing: Set the temperature of the internal mixer to 70°C and the rotor speed to 50 rpm; first, add 100 parts by weight of EPDM rubber and plasticize for 90 seconds; then add 5.0 parts by weight of zinc oxide and 1.0 parts by weight of stearic acid and continue mixing for 60 seconds; then add 42.5 parts by weight of the cerium-modified epoxy / carbon nanotube conductive slurry prepared in Example 1, which contains 10 parts by weight of multi-walled carbon nanotubes and 30 parts by weight of epoxidized soybean oil, and continue mixing for 4 minutes. The plasticizing and wetting effect of the epoxidized soybean oil in the slurry is used to promote dispersion. When the discharge temperature reaches 135°C, discharge the material to obtain the masterbatch. (2) Vulcanization: Adjust the roller temperature of the open mill to 50°C and the roller gap to 2mm; wrap the above masterbatch rubber around the roller, add 2.5 parts by weight of dicumyl peroxide and 1.5 parts by weight of triallyl isocyanurate, make triangular wrapping on the left and right sides 5 times each, and pass through thinly 3 times to make the vulcanization system evenly dispersed, and then sheet out to obtain unvulcanized rubber compound. (3) Extrusion and vulcanization: A rubber extruder is used, with the machine body temperature set to 75℃ and the die head temperature set to 95℃. The unvulcanized rubber compound is extruded onto the outer layer of a tin-plated copper conductor with a diameter of 2.5mm. Then it enters the continuous vulcanization pipeline CV line and is vulcanized at 170℃ for 20 minutes under a saturated steam pressure of 1.6MPa. After cooling, an anti-electromagnetic interference and radiation-resistant power cable is obtained.

[0043] Example 2: This embodiment provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable and its insulating material, including the following steps: (1) Mixing: Set the temperature of the internal mixer to 75°C and the rotor speed to 55 rpm; first, add 100 parts by weight of EPDM rubber and plasticize for 2 minutes; then add 4.0 parts by weight of zinc oxide and 0.8 parts by weight of stearic acid and mix for 1 minute; then add 55.0 parts by weight of cerium-modified epoxy / carbon nanotube conductive slurry prepared in Example 1, which contains about 12.9 parts by weight of multi-walled carbon nanotubes and 38.8 parts by weight of epoxy soybean oil, and continue mixing for 5 minutes. When the discharge temperature reaches 140°C, discharge the material to obtain the masterbatch. (2) Vulcanization: Adjust the roller temperature of the open mill to 55°C, wrap the masterbatch rubber around the roller, add 3.0 parts by weight of DCP and 2.0 parts by weight of TAIC, and make triangular wraps and thin passes according to conventional processes to obtain unvulcanized rubber material; (3) Extrusion and vulcanization: The unvulcanized rubber compound is extruded onto the outer layer of the conductor using an extruder. The extrusion process is the same as in Example 1. Subsequently, it is vulcanized for 25 minutes at 175°C and 1.5 MPa, and then cooled to obtain the cable.

[0044] Example 3: This embodiment provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable and its insulating material, including the following steps: (1) Mixing: Set the temperature of the internal mixer to 65°C and the rotor speed to 45 rpm; first, add 100 parts by weight of EPDM rubber and plasticize for 90 seconds; then add 3.0 parts by weight of zinc oxide and 0.5 parts by weight of stearic acid and mix for 60 seconds; then add 30.0 parts by weight of cerium-modified epoxy / carbon nanotube conductive slurry prepared in Example 1, which contains about 7.0 parts by weight of multi-walled carbon nanotubes and 21.1 parts by weight of epoxy soybean oil, and continue mixing for 4 minutes. When the discharge temperature reaches 130°C, discharge the material to obtain the masterbatch. (2) Vulcanization: Adjust the roller temperature of the open mill to 45°C, wrap the masterbatch around the roller, add 2.0 parts by weight of DCP and 1.0 parts by weight of TAIC, mix evenly and then sheet; (3) Extrusion and vulcanization: The extrusion process is the same as in Example 1; vulcanization is carried out at 165°C and 1.4 MPa for 15 minutes, and the cable is obtained after cooling.

[0045] Example 4: This embodiment provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable and its insulating material, the specific steps of which are as follows: (1) Mixing: The operation process is the same as in Example 1; the feed formula is: 100 parts by weight of EPDM rubber, 5.0 parts by weight of zinc oxide, 1.0 parts by weight of stearic acid, and 31.2 parts by weight of cerium-modified epoxy / carbon nanotube conductive slurry prepared in Preparation Example 2, which corresponds to 10 parts by weight of multi-walled carbon nanotubes, 20 parts by weight of epoxy soybean oil and the cerium salt and tannic acid content described in Preparation Example 2; the masterbatch is obtained; (2) Sulfurization: The operation process is the same as in Example 1; add 2.5 parts by weight of DCP and 1.5 parts by weight of TAIC, mix evenly and then sheet. (3) Extrusion and vulcanization: The process parameters are the same as in Example 1, and the cable is obtained.

[0046] Example 5: This embodiment provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable and its insulating material, the specific steps of which are as follows: (1) Mixing: The operation process is the same as in Example 1; the feed formula is: 100 parts by weight of EPDM rubber, 5.0 parts by weight of zinc oxide, 1.0 parts by weight of stearic acid, and 42.4 parts by weight of the cerium-modified epoxy / carbon nanotube conductive slurry prepared in Example 4, which contains 10 parts by weight of multi-walled carbon nanotubes and 30 parts by weight of epoxy soybean oil; to obtain the masterbatch; (2) Sulfurization: The operation process is the same as in Example 1; add 2.5 parts by weight of DCP and 1.5 parts by weight of TAIC, mix evenly and then sheet. (3) Extrusion and vulcanization: The process parameters are the same as in Example 1, and the cable is obtained.

[0047] Example 6: This embodiment provides a method for preparing an electromagnetic interference-resistant and radiation-resistant power cable and its insulating material, the difference being the use of a high-solids-content conductive paste. The specific steps are as follows: (1) Mixing: The operation process is the same as in Example 1; the feed formula is: 100 parts by weight of EPDM rubber, 5.0 parts by weight of zinc oxide, 1.0 parts by weight of stearic acid, and 53.8 parts by weight of cerium-modified epoxy / carbon nanotube conductive slurry prepared in Preparation Example 3, which corresponds to 10 parts by weight of multi-walled carbon nanotubes, 40 parts by weight of epoxy soybean oil and the tannic acid content described in Preparation Example 3; the masterbatch is obtained; (2) Sulfurization: The operation process is the same as in Example 1; add 2.8 parts by weight of DCP and 1.8 parts by weight of TAIC, mix evenly and then sheet. (3) Extrusion and vulcanization: The process parameters are the same as in Example 1, and the cable is obtained.

[0048] Comparative Example 1: Compared with Example 1, the difference is that the liquid phase transfer step is omitted, and a process of drying followed by mixing is adopted. Specifically, in Preparation Example 1, after step (2) is completed, epoxidized soybean oil is not added for vacuum distillation. Instead, the suspension is directly filtered, dried in a vacuum oven at 60°C for 24 hours, and ground into modified carbon nanotube powder. Subsequently, in the mixing step of Example 1, the powder is added to 30 parts by weight of epoxidized soybean oil by physical mixing, and the rest is the same.

[0049] Comparative Example 2: Compared with Example 1, the difference is that no cerium source catalyst was added when preparing the conductive paste. Specifically, in step (2) of Example 1, cerium acetylacetone was not added, and only tannic acid was used to treat the carbon nanotubes. The subsequent step (4) was changed to a heat treatment process under Lewis acid catalysis conditions, and the rest were the same.

[0050] Comparative Example 3: Compared with Example 1, the difference is that a non-reactive carrier is used instead of a reactive compatibilizer. Specifically, in step (3) of Preparation Example 1, an equal mass of liquid paraffin is used instead of epoxidized soybean oil. Since liquid paraffin does not contain epoxy groups, it cannot undergo a chemical grafting reaction with tannic acid. All other aspects are the same.

[0051] Comparative Example 4: Compared to Example 1, the difference lies in the use of a physical blending process without a pre-mixed slurry process. Specifically, the slurry preparation steps of Example 1 are omitted. Instead, 100 parts by weight of EPDM rubber, 10 parts by weight of raw multi-walled carbon nanotubes, 2.0 parts by weight of tannic acid, 0.5 parts by weight of cerium acetylacetone, 30 parts by weight of epoxidized soybean oil, and other additives from Example 1 are directly added to an internal mixer for mixing. All other aspects remain the same.

[0052] Comparative Example 5: Compared to Example 1, the difference lies in the use of a conventional organic antioxidant instead of cerium ions. Specifically, cerium acetylacetone is not added in Preparation Example 1, while 0.5 parts by weight of pentaerythritol ester antioxidant is added in the mixing step of Example 1, and the rest are the same.

[0053] Test Example 1: Evolution of Chemical Structure and Verification of Reaction Mechanism of Conductive Paste Experimental Description: This test is based on the general rules of infrared spectroscopy analysis method in GB / T 6040-2019. It examines the degree of chemical reaction between the components and the evolution of functional groups in the preparation of conductive paste by attenuated total reflection Fourier transform infrared spectroscopy analysis.

[0054] Experimental steps: (1) Pure epoxidized soybean oil, the cerium-modified epoxy / carbon nanotube conductive slurry obtained in Example 1, and the mixture obtained in Comparative Example 2 without cerium salt catalysis and only heat treatment were selected as test samples.

[0055] (2) The test was conducted using an attenuated total reflection Fourier transform infrared spectrometer equipped with a diamond crystal, with the spectral scanning range set to 4000 cm⁻¹. -1 Up to 500cm -1 4cm resolution -1 The number of scans was 32.

[0056] (3) Coat the sample onto the surface of an ATR crystal and collect infrared spectral data; at 1743 cm⁻¹ -1 The stretching vibration peak of the ester carbonyl group (C=O) was used as an internal standard, and the value was calculated to be 824 cm⁻¹. -1 Characteristic peaks of epoxy groups and 1085 cm⁻¹ -1 The relative absorbance ratio of the characteristic peaks of the ether bond (COC) characterizes the degree of functional group transformation.

[0057] Experimental data: Table 1: Data on the ratio of absorbance of characteristic peaks in infrared spectroscopy and changes in epoxy value in conclusion: According to Table 1 and Figure 1 Data shows that pure epoxidized soybean oil has a concentration of 824 cm⁻¹. -1 A distinct characteristic absorption peak of the ethylene oxide ring was observed. In Preparation Example 1, the intensity of this characteristic peak decreased significantly, with the relative absorbance ratio decreasing from 0.582 to 0.089, indicating a calculated epoxy group conversion rate of 84.71%. Meanwhile, Preparation Example 1 showed a significant decrease in the intensity of this characteristic peak at 1085 cm⁻¹. -1 A new absorption peak appears nearby, corresponding to the stretching vibration of aliphatic ether bonds (COC).

[0058] The data from Comparative Example 2 show that, without the addition of cerium ion catalyst, the conversion rate of epoxy groups after heat treatment was only 9.45%, and the characteristic peak of ether bond did not increase significantly, with the value increasing from 0.114 to 0.148. This indicates that the phenolic hydroxyl groups of tannic acid are difficult to open the high steric hindrance internal epoxy bonds of epoxidized soybean oil under catalytic conditions, and the two are mainly in a physical mixed state.

[0059] 3350cm -1 In the hydroxyl peak data, Comparative Example 2 had a higher intensity of 0.451, which originated from the unreacted phenolic hydroxyl groups of tannic acid; the intensity of Preparation Example 1 decreased to 0.315, indicating that some phenolic hydroxyl groups participated in the ring-opening etherification reaction.

[0060] Spectral data confirm that Ce 3+ Polarizing the epoxy bond and lowering the ring-opening activation energy promotes the chemical grafting of tannic acid phenolic hydroxyl groups with epoxidized soybean oil, forming a "carbon nanotube-tannic acid-chemical bond-epoxidized soybean oil" structure, thus achieving interfacial chemical bonding.

[0061] Test Example 2: Evaluation of the processing rheological properties and dispersion quality of the rubber compound Experimental Description: This test is based on GB / T 1232.1 and ASTM D6601 standards. The Mooney viscosity test and dynamic strain scanning of the rubber processing analyzer are used to examine the processing flow properties of the rubber compound and the degree of dispersion of fillers in the matrix.

[0062] Experimental steps: (1) The liquid phase transfer process rubber compound prepared in Example 1, the dry powder mixing process rubber compound prepared in Comparative Example 1, and the physical direct mixing process rubber compound prepared in Comparative Example 4 were selected as test samples.

[0063] (2) Use a Mooney viscometer and test according to GB / T 1232.1 standard. Set the mold cavity temperature to 125℃, preheat the rotor for 1 minute, rotate for 4 minutes, and record the final Mooney viscosity value [ML(1+4)@125℃].

[0064] (3) Dynamic strain scanning tests were performed using a rubber processing analyzer (RPA). The test temperature was set to 100℃, the frequency to 1Hz, and the strain scanning range was from 0.7% to 100%. The storage modulus at the lowest strain value of 0.7% was recorded. Storage modulus at 100% high strain value .

[0065] (4) Calculate the Payne effect value: The difference is used to characterize the strength of the packing network structure and the degree of packing aggregation.

[0066] Experimental data: Table 2: Mooney viscosity and RPA rheological data of rubber compounds prepared by different processes in conclusion: According to Table 2 and Figure 2 The data shows that the Mooney viscosity of Comparative Example 1 is as high as 92.4, and the Payne effect value is... The maximum viscosity reached 560.8 kPa. This indicates that during the dry preparation process, solvent evaporation led to strong van der Waals adsorption between carbon nanotubes, forming hard aggregates that were difficult to break down during subsequent mixing. These aggregates constructed a well-developed filler-filler network under low strain, resulting in a dramatic increase in modulus. However, under high shear, the network rapidly disintegrated, exhibiting extremely strong nonlinear viscoelasticity. The high viscosity also confirms the significant hindering effect of uneven filler dispersion on the flow of rubber molecular chains.

[0067] Comparative Example 4 The Pa value was 423.9 kPa, slightly better than Comparative Example 1 but still much higher than Example 1. Although physical direct mixing avoids hard agglomeration caused by drying, the high viscosity of the rubber melt cannot effectively wet the nanofillers due to the lack of solvent-mediated and chemical pre-dispersion. As a result, the carbon nanotubes exist in the form of micron-sized aggregates, and the interaction of the filler network is still strong.

[0068] The Mooney viscosity of Example 1 decreased to 55.3, and Only 184.3 kPa, compared to Comparative Example 1, This represents a reduction of approximately 67%. The low Payne effect directly confirms the effectiveness of the liquid-phase transfer process: after carbon nanotubes are monodispersed in the ethanol phase, they are transferred in situ to the epoxidized soybean oil phase through chemical bonding. Due to the steric hindrance effect of the epoxidized soybean oil molecular chains, the re-aggregation of carbon nanotubes is effectively isolated. Simultaneously, the epoxidized soybean oil grafted onto the filler surface acts as a molecular-level lubricant and a "soft interface," reducing friction between the filler and the matrix, significantly improving the processing fluidity of the compound, and ensuring the uniform distribution of the conductive medium in the matrix.

[0069] Test Example 3: Comprehensive Comparison of Electromagnetic Shielding Effectiveness and Basic Mechanical Properties Experimental Description: This test is based on GB / T 528 and GB / T 3048 standards. It comprehensively examines the mechanical properties, electrical conductivity and electromagnetic interference resistance of vulcanized rubber compounds through mechanical tensile testing, volume resistivity measurement and coaxial electromagnetic shielding effectiveness testing.

[0070] Experimental steps: (1) The final vulcanized rubber materials prepared in Examples 1 to 6 and Comparative Examples 1 to 5 were used as test objects. A 2 mm thick molded vulcanized sheet was cut into type 2 dumbbell-shaped specimens according to GB / T 528 standard for mechanical testing; at the same time, a coaxial ring specimen with an inner diameter of 3 mm and an outer diameter of 7 mm was prepared for electromagnetic shielding effectiveness testing.

[0071] (2) Using an electronic universal testing machine, a uniaxial tensile test was performed on the dumbbell-shaped specimen at a tensile rate of 500 mm / min at room temperature. The stress value at the moment of fracture was recorded. The stress value represents the tensile strength and strain value, and the strain value represents the elongation at break. Each group of samples was tested 5 times and the median was taken.

[0072] (3) Use a four-probe resistivity tester to measure the volume resistivity of the material.

[0073] (4) Using a vector network analyzer (VNA) and a coaxial test fixture, the test frequency range is set from 30MHz to 1.5GHz. The average value of the electromagnetic shielding effectiveness (SE) in this frequency band is recorded as SE_avg.

[0074] Experimental data: Table 3: Test results of mechanical and electromagnetic properties of each embodiment and comparative example in conclusion: according to Figure 3According to the data in Table 3, Example 1 exhibits a tensile strength of 13.4 MPa and an elongation at break of 345.2%, while maintaining an electromagnetic shielding effectiveness of 38.2 dB. Compared to Comparative Example 1, which uses a dry process, Example 1 demonstrates an approximately 56% improvement in shielding effectiveness and a three-order-of-magnitude reduction in volume resistivity. This indicates that the liquid-phase transfer process effectively prevents the hard aggregation of carbon nanotubes, lowers the percolation threshold, and forms a more complete conductive network. The agglomerates present in Comparative Example 1 cannot effectively reflect electromagnetic waves and, as stress concentration points, cause a significant decrease in elongation at break.

[0075] Comparing Example 1 with Comparative Example 3, which used liquid paraffin instead of epoxidized soybean oil, both used the same proportion of liquid carrier. However, Comparative Example 3 showed a tensile strength of only 7.2 MPa and an elongation at break of 156.8%. This difference in data confirms the crucial role of the chemical bridging mechanism: there is no chemical bond between white oil and tannic acid, resulting in weak interfacial adhesion. Under stress, the filler is easily detached from the matrix, leading to premature material fracture. In contrast, in Example 1, epoxidized soybean oil was grafted onto the surface of carbon nanotubes via cerium ion catalysis and participated in matrix vulcanization, forming a chemically continuous phase of "carbon nanotubes-epoxidized soybean oil-rubber matrix," effectively transferring stress.

[0076] The data trends of Examples 2 to 6 conform to the formulation design principles: increasing the amount of conductive paste significantly improved the shielding effectiveness. Although the flexibility decreased slightly, the elongation at break remained above 260%, meeting the cable bending radius requirements. The overall results indicate that this invention, through interfacial chemical design, solves the mechanical embrittlement problem commonly faced by highly filled conductive composite materials, achieving a balance between electromagnetic shielding function and mechanical flexibility.

[0077] Test Example 4: Radiation Aging Resistance and Lifespan Assessment Experimental Description: This test is conducted in accordance with GB / T 528 and related radiation aging test standards. The mechanical property retention rate and radiation aging stability of vulcanized rubber compounds under different radiation doses are examined through cobalt-60 gamma ray irradiation experiments.

[0078] Experimental steps: (1) Select the cerium-tannic acid-epoxidized soybean oil system vulcanized film prepared in Example 1, the cerium-free vulcanized film treated only with tannic acid prepared in Comparative Example 2, and the vulcanized film with added pentaerythritol ester antioxidant prepared in Comparative Example 5, and cut them into type 2 dumbbell-shaped samples conforming to GB / T 528 standard. 15 parallel samples were prepared for each group.

[0079] (2) Place the sample in 60 Irradiation aging experiments were conducted in an air environment using a Co-γ irradiation device. The irradiation dose rate was set to 5 kGy / h, and samples were removed when the cumulative dose reached 200 kGy and 500 kGy, respectively.

[0080] (3) The irradiated sample was left to stand at room temperature for 24 hours to eliminate the transient free radical effect. Its elongation at break was tested using an electronic universal testing machine with the tensile rate set to 500 mm / min.

[0081] (4) Calculate the elongation at break retention rate. Retention rate % = elongation at break after irradiation / initial elongation at break × 100%. Use this to evaluate the anti-aging performance and service life of the material under radiation environment.

[0082] Experimental data: Table 4: Changes in elongation at break and retention rate under different radiation doses in conclusion: according to Figure 4 According to the data in Table 4, the retention rate of Comparative Example 2 was only 57.19% at a dose of 200 kGy, and further decreased to 21.45% at 500 kGy. This indicates that in the absence of radiation-resistant additives, the EPDM matrix underwent severe radiation crosslinking and oxidative degradation under the action of gamma rays, resulting in extreme embrittlement of the material and rendering it unusable.

[0083] The comparison between Comparative Example 5 and Example 1 reveals the differences in the long-term effectiveness of different protective mechanisms. Under low-to-medium dose irradiation of 200 kGy, the retention rate of Comparative Example 5, with the addition of a conventional organic antioxidant, was 87.20%, not significantly different from the 92.29% of Example 1. This indicates that in the early stages of radiation, hindered phenolic antioxidants can effectively delay aging by capturing peroxide free radicals. However, when the cumulative irradiation dose reached 500 kGy, the retention rate of Comparative Example 5 dropped sharply to 44.00%. This is because organic antioxidants are "sacrificial" additives, irreversibly consumed under continuous high-energy radiation, losing their protective capabilities.

[0084] Conversely, Example 1, under high-dose irradiation of 500 kGy, maintained an elongation at break of 82.68%, nearly twice that of Example 5. This significant advantage confirms the effectiveness of cerium ions (Ce). 3+ / Ce 4+ The full life-cycle functional mechanism at the interface: Cerium ions are not disposable, but rather continuously quench radiation-generated hydroxyl radicals (HO radicals) through a reversible redox cycle. ) and peroxy free radicals (ROO) Furthermore, the long chains of epoxidized soybean oil grafted onto the surface of carbon nanotubes may undergo further cross-linking reactions during radiation aging. This cross-linking at the interface compensates for the performance loss caused by matrix degradation to a certain extent, thereby endowing the material with excellent high-dose radiation stability.

[0085] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An electromagnetic interference-resistant and radiation-resistant power cable, characterized in that, It includes a conductor core and an insulating shielding layer covering the conductor core; the insulating shielding layer is made of raw materials comprising the following parts by weight: 100 parts of EPDM rubber; 30.0-55.0 parts of cerium-modified epoxy / carbon nanotube conductive paste; 3.0-5.0 parts zinc oxide; Stearic acid 0.5-1.0 parts; 2.0-3.0 parts of dicumyl peroxide; Triallyl isocyanurate 1.0-2.0 parts; The cerium-modified epoxy / carbon nanotube conductive slurry is a composite material prepared by liquid-phase dispersion and in-situ chemical grafting reaction of multi-walled carbon nanotubes, tannic acid, cerium salt and epoxidized soybean oil.

2. The electromagnetic interference resistant and radiation-resistant power cable according to claim 1, characterized in that, The cerium-modified epoxy / carbon nanotube conductive paste is prepared by reacting components comprising the following parts by weight: 10 parts of multi-walled carbon nanotubes; Tannic acid 1.0-3.0 parts; 0.2-0.8 parts of cerium salt; 20-40 parts of epoxidized soybean oil.

3. The electromagnetic interference-resistant and radiation-resistant power cable according to claim 2, characterized in that, The EPDM rubber is a copolymer with an ethylene content of 65wt%-75wt% and an ethylene-bis(norbornene) content of 4.5wt%-9.0wt%; the cerium salt includes cerium(III) acetylacetone hydrate or anhydrous cerium(III) chloride.

4. A method for preparing an electromagnetic interference-resistant and radiation-resistant power cable, used to prepare the electromagnetic interference-resistant and radiation-resistant power cable according to any one of claims 1-3, characterized in that, Includes the following steps: S1. Preparation of conductive paste: Multi-walled carbon nanotubes are dispersed in an ethanol aqueous solution, tannic acid and cerium salt are added for adsorption, followed by the addition of epoxidized soybean oil. The ethanol aqueous solution is removed by vacuum distillation under vacuum conditions, and the reaction is carried out at a higher temperature to obtain cerium-modified epoxy / carbon nanotube conductive paste. S2. Mixing: Ethylene propylene diene monomer (EPDM) rubber, zinc oxide, stearic acid and the cerium-modified epoxy / carbon nanotube conductive slurry are mixed in an internal mixer to obtain masterbatch. S3. Vulcanization: Dicumyl peroxide and triallyl isocyanurate are added to the masterbatch, mixed evenly on a two-roll mill, and sheeted to obtain unvulcanized rubber compound. S4. Extrusion and vulcanization: The unvulcanized rubber compound is extruded onto the outer layer of the conductor core, and then vulcanized at high temperature and cooled to obtain the final product.

5. The method for preparing an anti-electromagnetic interference and radiation-resistant power cable according to claim 4, characterized in that, In step S1, the adsorption temperature is 25-40℃; the vacuum degree of the reduced pressure distillation is -0.08MPa to -0.09MPa; the temperature of the heating reaction is 110-140℃, and the reaction time is 1.5-2.0 hours.

6. The method for preparing an anti-electromagnetic interference and radiation-resistant power cable according to claim 4, characterized in that, In step S1, the amount of the ethanol-water solution used is 30-50 times the weight of the multi-walled carbon nanotubes; during the vacuum distillation process, the rotation speed of the shearing and stirring is 800-1500 rpm.

7. The method for preparing an anti-electromagnetic interference and radiation-resistant power cable according to claim 4, characterized in that, In step S2, the initial temperature of the internal mixer is set to 65-75℃, and the rotor speed is set to 45-55rpm. The mixing process is as follows: first, add EPDM rubber and plasticize for 90-120 seconds, then add zinc oxide and stearic acid and mix for 60 seconds, and finally add cerium-modified epoxy / carbon nanotube conductive slurry and continue mixing for 4-5 minutes. When the discharge temperature reaches 130-140℃, discharge the material.

8. The method for preparing an anti-electromagnetic interference and radiation-resistant power cable according to claim 4, characterized in that, In step S3, the roller temperature of the open mill is 45-55℃, and the roller gap is adjusted to 2mm; the operation of uniform mixing includes wrapping the masterbatch rubber around the rollers, adding dicumyl peroxide and triallyl isocyanurate, making triangular wraps on the left and right sides 5 times each, and passing through the mill 3 times.

9. The method for preparing an anti-electromagnetic interference and radiation-resistant power cable according to claim 4, characterized in that, In step S4, the extrusion is performed using a rubber extruder, with the machine body temperature set at 75°C and the die head temperature set at 95°C; the high-temperature vulcanization temperature is 165-175°C, the vulcanization time is 15-25 minutes, and the saturated steam pressure is 1.4-1.6 MPa.

10. The method for preparing an anti-electromagnetic interference and radiation-resistant power cable according to claim 4, characterized in that, In step S1, the concentration of the ethanol aqueous solution is 95%; the dispersion refers to treating the solution with an ultrasonic generator with a power of 400-800W for 30-60 minutes until a uniform suspension is formed.

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