High-temperature-resistant and anti-aging insulated wire and preparation method thereof

Abstract

This invention relates to the field of special cables and electrical equipment accessories, and particularly to a high-temperature resistant and anti-aging insulated conductor and its preparation method. The insulated conductor of this invention comprises a conductor and, from the inside out, an insulating wrapping layer, a high-temperature resistant and anti-aging varnish layer, and a braided sheath layer sequentially covering the conductor. The high-temperature resistant and anti-aging varnish layer contains a PCN-type metal-organic framework material, which has a nanoporous cage structure that specifically adsorbs oxygen. The preparation method includes: wrapping inorganic fiber filaments around the conductor to form an insulating wrapping layer, preparing a conductor core, coating the conductor core with a high-temperature resistant and anti-aging varnish and heating to cure it, and braiding inorganic fiber filaments as a sheath on the outermost layer. This invention, through the specific adsorption of oxygen by the PCN-type MOF material, effectively inhibits the decline in conductivity caused by conductor oxidation during long-term aging, reduces the damage to insulation performance caused by metal oxides, and allows the conductor to be used for a long time at 450°C. Even after high-temperature aging, it maintains excellent conductivity, insulation, and mechanical properties, making it suitable for fields such as nuclear power and aerospace equipment.

Description

Technical Field

[0001] This invention relates to the field of special cables and electrical equipment accessories, and in particular to a high-temperature resistant and anti-aging insulated wire and its preparation method. Background Technology

[0002] Insulated conductors are wires with one or more layers of electrical insulation material tightly wrapped around the conductor. They are widely used in electrical equipment, electronic circuits, and other fields, mainly for transmitting current and providing electrical isolation between the conductor and the external environment. With the increasing demands for reliability in electrical systems from high-end equipment such as nuclear power and aerospace, conductors not only need to possess excellent conductivity and insulation properties, but also must maintain long-term stable operation in harsh environments such as high temperature and high oxygen levels.

[0003] Currently, a common method to improve the high-temperature resistance of conductors is to plate a metal layer, such as nickel or silver, onto the conductor surface. This forms a dense metal protective layer to isolate the conductor from the air and slow down the high-temperature oxidation process. However, in practical applications, it has been found that during long-term high-temperature service, the difference in thermal expansion coefficients between the metal plating and the base conductor, as well as the volume expansion caused by the oxidation reaction of the plating material itself at high temperatures, leads to interfacial structural instability, resulting in a significant decrease in the conductor's conductivity and mechanical strength. More importantly, at high temperatures, metallic elements easily diffuse into the outer insulation layer of the conductor, forming conductive pathways and compromising the integrity of the insulation structure, thereby reducing the overall electrical insulation performance of the conductor.

[0004] Furthermore, the long-term aging problem of existing insulated wires under high-temperature environments has not been effectively solved. Issues such as increased resistance due to conductor oxidation, breakdown risk caused by insulation material deterioration, and damage to structural integrity severely restrict their application in fields with extremely high reliability requirements, such as nuclear power and aerospace.

[0005] Therefore, developing an insulated conductor that can resist long-term high-temperature aging and maintain excellent conductivity, mechanical strength and insulation properties throughout its service life has significant engineering application value and market prospects. Summary of the Invention

[0006] In view of the problem that the conductivity and insulation properties of existing insulated wires decrease significantly after long-term high-temperature aging, the present invention provides a high-temperature resistant and anti-aging insulated wire and its preparation method, which can be used for a long time at 450°C and has excellent thermal stability and anti-aging properties.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] The first aspect of the present invention provides a high-temperature resistant and anti-aging insulated wire, comprising a conductor and an insulating wrapping layer, a high-temperature resistant and anti-aging varnish layer, and a braided sheath layer sequentially wrapped around the conductor from the inside out;

[0009] The high-temperature resistant and anti-aging paint layer contains a PCN-type metal-organic framework material, which has a nanoporous cage structure that specifically adsorbs oxygen.

[0010] A second aspect of the present invention provides a method for preparing the aforementioned high-temperature resistant and anti-aging insulated wire, comprising the following steps:

[0011] (1) An insulating wrapping layer is formed by wrapping one or more layers of inorganic fiber filaments around the conductor to obtain the wire core;

[0012] (2) Coat the outer surface of the core with a high-temperature resistant and anti-aging paint and heat to cure it to form a high-temperature resistant and anti-aging paint layer;

[0013] (3) Inorganic fiber filaments are woven into the outer layer of the high temperature resistant and anti-aging paint layer to form a woven sheath layer.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] 1. The insulated conductor provided by this invention adopts a composite structure of an insulating wrapping layer, a high-temperature resistant and anti-aging varnish layer, and a braided sheath layer. It can be used for extended periods at 450℃, and compared to ordinary conductors, its thermal stability and anti-aging performance at high temperatures are significantly improved. The conductor incorporates the specific oxygen adsorption characteristics of the PCN-type metal-organic framework material's nanoporous cage structure, inhibiting the decline in conductivity caused by conductor oxidation during long-term aging. Simultaneously, it reduces the damage to the conductor's insulation performance caused by metal oxides generated during conductor oxidation, enhancing the conductor's thermal stability, reliability, and long service life. Testing shows that after aging at 450℃ for 168 hours, the high-temperature insulation resistance of the conductor can reach 170-280 MΩ·m, and the conductivity can reach 68%-72% IACS. The surface of the conductor does not crack after being wound with a 40D round rod.

[0016] 2. This invention, through the synergistic effect of the insulating wrapping layer, the high-temperature resistant and anti-aging paint layer containing PCN type MOFs, and the braided sheath layer, avoids the impact of conductor oxidation failure on the overall performance. After long-term high and low temperature cycle aging, it can still maintain high conductivity and insulation performance, significantly improving the reliability and long service life of the wire.

[0017] 3. This invention further enhances the conductor's resistance to high-temperature softening and creep by using alumina-dispersed copper as the conductor material; it improves insulation performance by using alkali-free glass fiber as the insulating wrapping layer; and it enhances the conductor's mechanical strength and abrasion resistance by using alumina fiber as the braided sheath layer. Simultaneously, this invention simplifies the conductor's production process through structural design and process optimization. The wrapping, coating, and braiding processes are carried out continuously in the preparation method, with relatively low processing temperatures (90~120℃), low energy consumption, and a linear speed of 0.2~1.0 m / min, effectively improving product production efficiency and demonstrating promising prospects for industrial application.

[0018] 4. The high-temperature resistant and anti-aging insulated wire provided by this invention can be widely used in technical fields with high reliability and long service life requirements, such as nuclear power and aerospace equipment. It can effectively reduce the impact of wire aging on the overall equipment reliability and enhance the market competitiveness of signal or power transmission insulated wires. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a high-temperature resistant and anti-aging insulated wire provided in an embodiment of the present invention.

[0020] Figure label:

[0021] 1-Conductor; 2-Insulating wrapping layer; 3-High temperature resistant and anti-aging paint layer; 4-Braided sheath layer. Detailed Implementation

[0022] The following details the high-temperature resistant and anti-aging insulated wire of the present invention and its preparation method.

[0023] The first aspect of the present invention provides a high-temperature resistant and anti-aging insulated wire, comprising a conductor and an insulating wrapping layer, a high-temperature resistant and anti-aging varnish layer, and a braided sheath layer sequentially wrapped around the conductor from the inside out;

[0024] The high-temperature resistant and anti-aging paint layer contains a PCN-type metal-organic framework material, which has a nanoporous cage structure that specifically adsorbs oxygen.

[0025] The high-temperature resistant and anti-aging insulated wire of this invention adopts a multi-layer composite structure. The insulating wrapping layer directly covers the conductor surface, its main function being to provide basic electrical insulation performance for the wire, and simultaneously serving as an adhesion substrate for the intermediate layer, ensuring good adhesion between the subsequent varnish layer and the conductor. The high-temperature resistant and anti-aging varnish layer, covering the insulating wrapping layer, is the core functional layer of the high-temperature resistant and anti-aging insulated wire. It contains PCN-type metal-organic framework materials (PCN-MOFs) with specific oxygen adsorption capabilities, effectively inhibiting the diffusion of oxygen molecules to the conductor surface under high-temperature conditions, thereby delaying the oxidation process of the conductor. The braided sheath layer, as the outermost structure, forms a dense protective layer through tightly woven inorganic fibers, effectively resisting external mechanical damage, while further enhancing the high-temperature resistance and structural integrity of the high-temperature resistant and anti-aging insulated wire.

[0026] In some embodiments of the present invention, the conductor is a metal wire with a surface-coated layer that has undergone annealing treatment. Annealing treatment can increase the conductivity and flexibility of the conductor, which is beneficial to improving the electrical conductivity and mechanical properties of the wire. The surface-coated layer can increase the high-temperature resistance and corrosion resistance of the conductor, which is beneficial to improving the high-temperature resistance and aging resistance of the wire.

[0027] Preferably, the metal wire is selected from copper wire, silver wire, copper-silver alloy wire, and alumina-dispersed copper wire; the plating is selected from nickel plating or silver plating.

[0028] More preferably, the metal wire is an alumina-dispersed copper wire, and the mass fraction of aluminum in the alumina-dispersed copper wire is 0.03%~0.35%. For example, the mass fraction of aluminum can be 0.03%~0.05%, 0.05%~0.10%, 0.10%~0.15%, 0.15%~0.20%, 0.20%~0.25%, 0.25%~0.30%, or 0.30%~0.35%. The nano-alumina particles in the alumina-dispersed copper wire can effectively hinder the migration of copper ions, inhibit the oxidation and corrosion of the metal conductor, and significantly improve the conductivity and mechanical strength of the wire after high-temperature aging. It should be noted that an excessively high proportion of aluminum will lead to an increase in the alumina content, which in turn will reduce the conductivity of the alumina-dispersed copper wire; therefore, it needs to be controlled within the above-mentioned preferred range.

[0029] In this invention, the insulating wrapping layer is made of inorganic fibers, which provides basic insulation performance for the conductor and provides a substrate for the adhesion and penetration of the high-temperature resistant and anti-aging paint layer.

[0030] In some embodiments of the present invention, the insulating wrapping layer comprises one or more layers of inorganic fibers, wherein the inorganic fibers are selected from one or a combination of several of alkali-free glass fibers, high-silica glass fibers, quartz fibers, alumina fibers, zirconium oxide fibers, or basalt fibers. For example, it can be alkali-free glass fibers, quartz fibers, a combination of high-silica glass fibers and zirconium oxide fibers, a combination of quartz fibers and basalt fibers, or a combination of alkali-free glass fibers, high-silica glass fibers, and basalt fibers.

[0031] Preferably, the inorganic fibers of the insulating wrapping layer are alkali-free glass fibers with a linear density of 1~20 Tex. For example, the linear density can be 1~5 Tex, 5~10 Tex, 10~15 Tex, or 15~20 Tex. Alkali-free glass fibers have good flexibility, strong processability, high volume resistivity, and extremely low alkali metal content, which can prevent the precipitation of alkali metal oxides from affecting the insulation performance. This is beneficial to improving the insulation performance of the conductor after high-temperature aging, while significantly reducing material costs. When the linear density is low, it is less likely to break fibers or generate burrs during wrapping, and the insulation layer formed by the fiber wrapping is denser.

[0032] In this invention, the high-temperature resistant and anti-aging coating layer comprises PCN-type metal-organic framework materials (PCN-MOFs). PCN-type metal-organic framework materials possess a unique nanoporous cage structure, capable of specifically adsorbing oxygen, thereby inhibiting the decline in conductivity caused by conductor oxidation during long-term aging and reducing the damage to insulation performance caused by metal oxides generated from conductor oxidation. PCN-MOFs are composed of rare earth metal ions (such as Yb). 3+ Er 3+ PCN-MOFs are three-dimensional porous crystalline materials formed by the self-assembly of organic ligands (such as 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine) through coordination bonds, exhibiting a nanoscale pore cage structure (pore size typically in the range of 0.5~1.0 nm). PCN-MOFs can be commercially available products or prepared using methods known in the art. The proposed mechanism of action is based on the following: the organic ligands in PCN-MOFs are covalently linked to rare earth metal ions, forming an interwoven pore cage structure. This interpenetrating covalent bond further restricts the pore size, resulting in specific adsorption of oxygen molecules within the coating layer, thus achieving selective oxygen capture. Simultaneously, the interpenetrating covalent bonds between the ligands and the interwoven pore cage structure provide high thermal stability (withstanding temperatures above 450°C), thus maintaining effective oxygen capture capability even at high temperatures. It should be noted that the above mechanism analysis is only for understanding the technical principles of this invention and does not constitute any limitation on the scope of protection of this invention.

[0033] In some embodiments of the present invention, the high-temperature resistant and anti-aging paint layer comprises one or more layers of high-temperature resistant and anti-aging paint. Preferably, the high-temperature resistant and anti-aging paint comprises the following components and parts by weight: 0.5 to 2 parts by weight of silane coupling agent, 1 to 3 parts by weight of inorganic filler, 5 to 10 parts by weight of dimethyl sulfoxide, 10 to 30 parts by weight of PCN-type metal-organic framework material, and 80 to 120 parts by weight of organosilicon resin.

[0034] The silane coupling agent is used to enhance the bonding force between the components of the high-temperature resistant and anti-aging paint, as well as between the paint layer and the inner and outer inorganic fibers, promoting interfacial compatibility. The silane coupling agent can be one or a combination of several of methyltrimethoxysilane, vinyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, (3-mercaptopropyl)trimethoxysilane, and 3-methacryloyloxypropyltrimethoxysilane. The weight percentage of the silane coupling agent is 0.5–2, and can be any value within this range, such as 0.5–0.9, 1–1.5, or 1.6–2.

[0035] Inorganic fillers are used to improve the heat resistance and insulation properties of the high-temperature resistant and anti-aging paint. The inorganic filler can be one or a combination of several of fumed silica, nano-alumina, and zirconium oxide. The average particle size of the inorganic filler is preferably from 10 nm to 1 μm. The weight percentage of the inorganic filler is 1 to 3, and can be any value within this range, for example, 1 to 1.5, 1.5 to 2, 2 to 2.5, or 2.5 to 3.

[0036] Dimethyl sulfoxide is used to adjust the viscosity of the high-temperature resistant and anti-aging paint and enhance the uniformity of dispersion of each component in the paint. The weight of dimethyl sulfoxide is 5 to 10, and can be any value within this range, such as 5 to 6, 7 to 8, or 9 to 10.

[0037] Organosilicon resin is used to improve the adhesion and insulation properties of the high-temperature resistant and anti-aging paint. The organosilicon resin can be one or a combination of several of methylethoxy polysiloxane silicone resin, ethoxyphenyl polysiloxane resin, epoxy-modified polysiloxane resin, and organopolysilazane resin. The organosilicon resin has a weight ratio of 80-120, and can be any value within this range, such as 80-90, 91-100, 101-110, or 111-120.

[0038] In some embodiments of the present invention, the high-temperature resistant and anti-aging paint is prepared by a method comprising the following steps: taking each component according to the weight ratio, adding inorganic filler and dimethyl sulfoxide to an organosilicon resin, mixing evenly, adding PCN-type metal-organic framework material and silane coupling agent, and mechanically stirring to obtain the final product. In some embodiments of the present invention, after uniform mechanical stirring, the temperature is raised to 55~65℃ (e.g., 55℃, 58℃, 60℃, 62℃, 65℃), and mechanical stirring is continued for 3~4 hours (e.g., 3 hours, 3.5 hours, 4 hours). In some embodiments of the present invention, the viscosity of the high-temperature resistant and anti-aging paint is adjusted with xylene before use, and measured using a Forecast-4 viscometer, controlling the outflow time to be 40~160 s (e.g., 40s, 50s, 100s, 120s, 140s, 160s).

[0039] In some embodiments of the present invention, the PCN-type metal-organic framework material is formed by coordination of rare earth metal ions with the organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine.

[0040] In some embodiments of the present invention, the rare earth metal ion is one of erbium ion, dysprosium ion, ytterbium ion, and yttrium ion.

[0041] In some embodiments of the present invention, the PCN-type metal-organic framework material is prepared by a solvothermal reaction of a rare earth metal nitrate and an organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine. Specifically, the process includes the following steps: adding the rare earth metal nitrate and the organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine to an organic solvent, mixing thoroughly, then adding hydrogen peroxide solution, placing the mixture in a sealed reaction vessel, heating to 142~148℃ (e.g., 142℃, 145℃, 148℃), maintaining the temperature for 60~80 h (e.g., 60 h, 72 h, 80 h), cooling to 30~38℃ (e.g., 30℃, 35℃, 38℃), washing, and vacuum drying to obtain the final product.

[0042] In some embodiments of the present invention, the molar ratio of rare earth metal nitrate to organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine is 1 to 3:1, preferably 2:1.

[0043] In some embodiments of the present invention, the organic solvent is a polar aprotic solvent, such as dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-diethylformamide (DEF), N-methylpyrrolidone (NMP), etc., and more preferably dimethyl sulfoxide. The amount of organic solvent added can be determined according to the total amount of reactants and the volume of the reaction vessel, for example, 5-10 mL, to ensure complete dissolution of the reactants and maintain a suitable reaction concentration and pressure.

[0044] In some embodiments of the present invention, the concentration of the hydrogen peroxide solution is 25%~35% (w / w), which can be 25%~30% (w / w) or 30%~35% (w / w). The amount added is determined based on the amount of rare earth metal nitrate and the volume of organic solvent in the reaction system, to ensure that the hydrogen peroxide can exert sufficient oxidizing effect to promote the coordination reaction in the reaction system, without causing excessive pressure in the reaction system or introducing too much water, thus affecting crystal formation. Those skilled in the art can appropriately adjust the amount of hydrogen peroxide added within the above range according to the volume of the reaction vessel and the total amount of reactants, for example, it can be 1~2 mL.

[0045] In some embodiments of the present invention, the washing medium is the same as the aforementioned organic solvent, and the number of washing cycles is 2 to 3.

[0046] In this invention, the braided sheath layer is made of inorganic fibers, which can protect the inner structure from external mechanical damage and enhance the bending and winding resistance of the conductor. The braided sheath layer includes at least one layer of inorganic fibers; for example, the number of inorganic fiber layers can be one, two, or three. In some embodiments of this invention, the inorganic fibers are selected from one or more combinations of alkali-free glass fibers, high-silica glass fibers, quartz fibers, alumina fibers, zirconium oxide fibers, or basalt fibers. For example, it can be alkali-free glass fibers, quartz fibers, a combination of high-silica glass fibers and zirconium oxide fibers, a combination of quartz fibers and basalt fibers, or a combination of alkali-free glass fibers, high-silica glass fibers, and basalt fibers.

[0047] Preferably, the inorganic fiber of the braided sheath layer is alumina fiber with a linear density of 10~400 Tex, which can be 10~20 Tex, 20~40 Tex, 40~60 Tex, 60~80 Tex, 80~100 Tex, 100~200 Tex, 200~300 Tex, or 300~400 Tex. Alumina fiber has high mechanical strength and good abrasion resistance, and as a sheath, it can effectively prevent mechanical damage to the inner structure of the conductor. Alumina fiber with a relatively high linear density has high tensile strength, is not easy to break during weaving, and is beneficial to strengthening the mechanical properties of the braided sheath layer.

[0048] A second aspect of the present invention provides a method for preparing a high-temperature resistant and anti-aging insulated wire as described in the first aspect, comprising the following steps:

[0049] (1) An insulating wrapping layer is formed by wrapping one or more layers of inorganic fiber filaments around the conductor to obtain the wire core;

[0050] (2) Coat the outer surface of the core with a high-temperature resistant and anti-aging paint and heat to cure it to form a high-temperature resistant and anti-aging paint layer;

[0051] (3) Inorganic fiber filaments are woven into the outer layer of the high temperature resistant and anti-aging paint layer to form a woven sheath layer.

[0052] In some embodiments of the present invention, in step (1), the number of wrapping layers of the inorganic fiber filament is 1 to 6 layers, which can be 1, 2, 3, 4, 5, or 6 layers. In some embodiments of the present invention, the wrapping method can adopt conventional wrapping processes such as overlapping wrapping, gap wrapping, or flat wrapping.

[0053] In some embodiments of the present invention, in step (2), the heating and curing temperature is 90~120℃, which can be 90~100℃, 100~110℃, or 110~120℃; the heating and curing time is 10~20min, which can be 10~12min, 12~14min, 14~16min, 16~18min, or 18~20min; the linear velocity is 0.2~1.0m / min, which can be 0.2~0.4 m / min, 0.4~0.6 m / min, 0.6~0.8 m / min, or 0.8~1.0 m / min. The linear velocity refers to the travel speed of the conductor during the coating and curing process.

[0054] In some embodiments of the present invention, in step (2), the coating is an immersion coating, and the number of coating layers is 2 to 4, for example, 2, 3 or 4 layers. Each coating layer is heated and cured to form a high-temperature resistant and anti-aging paint layer.

[0055] In some embodiments of the present invention, in step (3), the weaving density of the inorganic fiber filament is 80%~100%, which can be 80%~85%, 85%~90%, 90%~95%, or 95%~100%. In some embodiments of the present invention, the weaving method can adopt conventional weaving processes such as plain weave, twill weave, or satin weave.

[0056] The following detailed description of specific embodiments of the present invention, in conjunction with preferred embodiments, further illustrates the relevant details. When numerical ranges are given in the embodiments, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range, as well as any value between the two endpoints, may be selected. Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by those skilled in the art. In addition to the specific methods, devices, and materials used in the embodiments, the present invention can be implemented using any prior art methods, devices, and materials similar to or equivalent to those described in the embodiments of the present invention, provided that those skilled in the art possess the prior art and the description of the present invention.

[0057] Example 1

[0058] (1) Preparation of PCN-type metal-organic framework materials

[0059] 30 mmol of ytterbium nitrate and 15 mmol of the organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine were added to 8 mL of dimethyl sulfoxide and mixed thoroughly. Then, 1.5 mL of 30% (w / w) hydrogen peroxide solution was added, and the mixture was placed in a reaction vessel, sealed, heated to 145 °C, maintained for 72 h, cooled to 35 °C, washed three times with dimethyl sulfoxide, and then vacuum dried to obtain the PCN-type metal-organic framework material.

[0060] (2) Preparation of high temperature resistant and anti-aging paint

[0061] Weigh the following components by weight: 100 parts of organosilicon resin (including 2 parts of ethoxyphenyl polysiloxane resin and 1 part of organosilazane resin), 2.4 parts of inorganic filler (including 3 parts of fumed silica, 3 parts of nano alumina, and 1 part of zirconium oxide), 8 parts of dimethyl sulfoxide, 20 parts of PCN type metal-organic framework material, and 1 part of silane coupling agent ((3-mercaptopropyl)trimethoxysilane).

[0062] Inorganic fillers and dimethyl sulfoxide are added to the silicone resin and mixed evenly. PCN type metal-organic framework material and silane coupling agent are added, and the mixture is mechanically stirred. The temperature is raised to 60±3℃ and mechanically stirred for 3.5 hours. Before use, the viscosity is adjusted with xylene (22~24℃, Ford-4 viscometer) to a flow time of 100 s to obtain a high-temperature resistant and anti-aging paint.

[0063] (3) Preparation of high temperature resistant and anti-aging insulated wires

[0064] S1. A nickel-plated alumina-dispersed copper round wire with a diameter of 0.5 mm is selected as the conductor. The mass fraction of aluminum in the alumina-dispersed copper is 0.15%, and the nickel plating grade is 4. 24 spindles of alkali-free glass fiber with a linear density of 4.5 Tex are used to wrap 3 layers of alkali-free glass fiber around the conductor to form an insulating wrapping layer.

[0065] S2. Apply high-temperature resistant and anti-aging paint to the above-mentioned wire core by impregnation coating. Apply 3 coats, and after each coat, heat and cure in an oven at 110°C for 15±1 min at a linear speed of 0.6 m / min to form a high-temperature resistant and anti-aging paint layer.

[0066] S3. The outermost layer is formed by weaving 16 spindles of alumina fiber with a linear density of 67 Tex to form a braided sheath layer with a braiding density of 94%, thus obtaining the high-temperature resistant and anti-aging insulated wire of this embodiment.

[0067] Example 2

[0068] This embodiment is basically the same as Embodiment 1, except that the nickel plating grade used for the conductor is grade 2; the mass fraction of aluminum in the alumina-dispersed copper is 0.05%; and two coats of high-temperature resistant and anti-aging paint are applied.

[0069] Example 3

[0070] This embodiment is basically the same as Embodiment 1, except that the number of inorganic fiber wrapping layers on the conductor is 4; and the high-temperature resistant and anti-aging paint is applied in 4 coats.

[0071] Comparative Example 1

[0072] This comparative example is basically the same as Example 1, except that the conductor is oxygen-free copper round wire.

[0073] Comparative Example 2

[0074] This comparative example is basically the same as Example 1, except that PCN-type metal-organic framework material is not added to the high-temperature resistant and anti-aging paint.

[0075] Comparative Example 3

[0076] This comparative example is basically the same as Example 1, except that the outermost layer does not have a woven sheath layer.

[0077] Comparative Example 4

[0078] This comparative example is basically the same as Example 1, except that 3A type molecular sieve is used instead of PCN type metal-organic framework material.

[0079] Performance testing

[0080] The following performance tests were performed on the finished wires prepared in Examples 1-3 and Comparative Examples 1-4:

[0081] 1. Insulation performance test

[0082] The conductor was heated at 450℃ for 168 hours, and then its insulation resistance was tested. Test method: GB / T 3048.5-2007 "Electrical Performance Tests for Wires and Cables - Part 5: Insulation Resistance Test", voltage-current method. Requirement: High-temperature insulation resistance ≥100MΩ·m.

[0083] 2. Mechanical performance testing

[0084] The conductor is heated at 450℃ for 168 hours and wound onto a round rod with a diameter 40 times that of the conductor. The surface should not crack after winding. Test method: GB / T 4074.3-2024 "Test Methods for Winding Wires Part 3: Mechanical Properties", visual inspection with normal vision.

[0085] 3. Conductivity test

[0086] The conductor was heated at 450°C for 168 hours, and then its conductivity was tested. Test method: ASTM B193. Requirement: Conductivity ≥ 60% IACS.

[0087] The test results are shown in Table 1 below.

[0088] Table 1 Performance Test Results

[0089]

[0090] The test results in Table 1 show that:

[0091] The high-temperature resistant and anti-aging insulated wires prepared in Examples 1-3, after aging at 450℃ for 168 h, all achieved a high-temperature insulation resistance of over 170 MΩ·m, far exceeding the requirement of 100 MΩ·m; their conductivity all reached over 68% IACS, exceeding the requirement of 60% IACS; and the surface of the 40D round bars did not crack after winding, indicating good mechanical properties.

[0092] Comparative Example 1 used oxygen-free copper conductors without the addition of alumina-dispersed copper. Its insulation performance (5.1 MΩ·m) and conductivity performance (57% IACS) did not meet the requirements, and its mechanical properties were unqualified (surface cracking). This indicates that alumina-dispersed copper conductors play an important role in improving the high-temperature aging resistance of conductors.

[0093] Comparative Example 2, without the addition of PCN-MOFs, failed to meet the required insulation performance (9.6 MΩ·m) and conductivity performance (54% IACS), indicating that the oxygen adsorption function of PCN-MOFs is crucial for inhibiting conductor oxidation and maintaining the conductivity and insulation performance of the wire.

[0094] Comparative Example 3 did not have a braided sheath layer, and its mechanical properties were unqualified (surface cracking). Although its insulation performance (15 MΩ·m) was better than that of Comparative Examples 1 and 2, it still did not meet the requirements, indicating that the braided sheath layer is indispensable for protecting the inner structure.

[0095] Comparative Example 4 used type 3A molecular sieve instead of PCN-MOFs. Its insulation performance (11 MΩ·m) and conductivity performance (56% IACS) did not meet the requirements. This indicates that although type 3A molecular sieve has adsorption function, its pore structure is not specifically for oxygen adsorption and cannot achieve the technical effect of PCN-MOFs.

[0096] In summary, this invention, by employing a composite structure of an insulating wrapping layer, a high-temperature resistant and anti-aging varnish layer containing PCN-MOFs, and a braided sheath layer, and preferably using an alumina-dispersed copper conductor, achieves the technical effect of maintaining excellent conductivity, insulation, and mechanical properties of the conductor after long-term aging at 450℃, thus solving the technical problem of a sharp decline in performance after long-term high-temperature aging in the prior art.

[0097] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A high-temperature resistant and anti-aging insulated wire, characterized in that, It includes a conductor (1) and an insulating wrapping layer (2), a high-temperature resistant and anti-aging paint layer (3), and a braided sheath layer (4) that are sequentially wrapped around the conductor (1) from the inside out. The high-temperature resistant and anti-aging paint layer (3) contains a PCN-type metal-organic framework material, which has a nanoporous cage structure that specifically adsorbs oxygen.

2. The high-temperature resistant and anti-aging insulated wire as described in claim 1, characterized in that, Includes one or more of the following characteristics: (a) The conductor (1) is a metal wire with a surface coating that has undergone annealing treatment; (b) The insulating wrapping layer (2) comprises one or more layers of inorganic fibers, wherein the inorganic fibers are selected from one or more combinations of alkali-free glass fibers, high silica glass fibers, quartz fibers, alumina fibers, zirconium oxide fibers or basalt fibers; (c) The high-temperature resistant and anti-aging paint layer (3) includes one or more layers of high-temperature resistant and anti-aging paint; (d) The PCN-type metal-organic framework material is formed by coordination of rare earth metal ions with the organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine; (e) The woven sheath layer (4) includes one or more layers of inorganic fibers, wherein the inorganic fibers are selected from one or more combinations of alkali-free glass fibers, high silica glass fibers, quartz fibers, alumina fibers, zirconium oxide fibers or basalt fibers.

3. The high-temperature resistant and anti-aging insulated wire as described in claim 2, characterized in that, Includes one or more of the following characteristics: (a1) The metal wire is selected from one of copper wire, silver wire, copper-silver alloy wire and alumina-dispersed copper wire; the plating is selected from one of nickel plating or silver plating; (b1) The inorganic fibers of the insulating wrapping layer (2) are selected from alkali-free glass fibers, and their linear density is 1~20Tex; (c1) The high-temperature resistant and anti-aging paint comprises the following components and parts by weight: 0.5 to 2 parts by weight of silane coupling agent, 1 to 3 parts by weight of inorganic filler, 5 to 10 parts by weight of dimethyl sulfoxide, 10 to 30 parts by weight of PCN type metal-organic framework material and 80 to 120 parts by weight of organosilicon resin. (d1) The rare earth metal ion is one of erbium ion, dysprosium ion, ytterbium ion, and yttrium ion; (e1) The inorganic fiber of the braided sheath layer (4) is alumina fiber with a linear density of 10~400Tex.

4. The high-temperature resistant and anti-aging insulated wire as described in claim 3, characterized in that, The metal wire is an alumina-dispersed copper wire, and the mass fraction of aluminum in the alumina-dispersed copper wire is 0.03%~0.35%.

5. The high-temperature resistant and anti-aging insulated wire as described in claim 3, characterized in that, The high-temperature resistant and anti-aging paint is prepared by a method including the following steps: taking each component according to the weight ratio, adding inorganic filler and dimethyl sulfoxide to the organosilicon resin, mixing evenly, adding PCN type metal-organic framework material and silane coupling agent, and mechanically stirring to obtain the final product.

6. The high-temperature resistant and anti-aging insulated wire as described in claim 5, characterized in that, Includes one or more of the following characteristics: (a) After mechanical stirring until homogeneous, heat to 55~65℃ and continue mechanical stirring for 3~4 hours; (b) Before use, xylene is added to adjust the viscosity of the high-temperature resistant and anti-aging paint. The viscosity is measured using a Forte 4 viscometer, and the outflow time is controlled to be 40-160 seconds.

7. The high-temperature resistant and anti-aging insulated wire as described in claim 2, characterized in that, The PCN-type metal-organic framework material is prepared by a solvothermal reaction of rare earth metal nitrates with the organic ligand 2,4,6-tris(4-carboxyphenyl)-1,3,5-triazine.

8. A method for preparing a high-temperature resistant and anti-aging insulated wire as described in any one of claims 1 to 6, characterized in that, Includes the following steps: (1) An insulating wrapping layer is formed by wrapping one or more layers of inorganic fiber filaments around the conductor to obtain the wire core; (2) Coat the outer surface of the core with a high-temperature resistant and anti-aging paint and heat to cure it to form a high-temperature resistant and anti-aging paint layer; (3) Inorganic fiber filaments are woven into the outer layer of the high temperature resistant and anti-aging paint layer to form a woven sheath layer.

9. The method for preparing a high-temperature resistant and anti-aging insulated conductor as described in claim 8, characterized in that, Includes one or more of the following characteristics: (a) In step (1), the number of inorganic fiber wrapping layers is 1 to 6; (b) In step (2), the heating curing temperature of the high-temperature resistant and anti-aging paint is 90~120℃, the heating curing time is 10~20min, and the linear velocity is 0.2~1.0m / min; (c) In step (3), the weaving density of the inorganic fiber filament is 80%~100%.

10. The preparation method according to claim 8 or 9, characterized in that, In step (2), the coating is an immersion coating, with 2 to 4 coating layers, and each layer is heated and cured after coating.

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