High-performance multifunctional cable and method for manufacturing the same

Abstract

The application discloses a kind of high-performance multifunctional cable and preparation method thereof, belong to cable technical field, including the following steps: step one: nickel titanium wire is stretched to produce strain, after insulating layer is coated on its surface, shape memory alloy wire is obtained, shape memory alloy wire is tightly fixed in the inner cavity of polytetrafluoroethylene mold;Step two: the solution of phenolic resin prepolymer containing thermochromic microcapsule, MXene / ethanol dispersion, silica sol are mixed to obtain mixed sol, the pH value of mixed sol is adjusted, multifunctional composite sol is obtained after stirring;Step three: multifunctional composite sol is injected into polytetrafluoroethylene mold in which shape memory alloy wire has been fixed, and modified multifunctional composite gel is obtained after gelation and modification;Step four: modified multifunctional composite gel is supercritical CO2 drying, and multifunctional composite aerogel is obtained;Step five: multifunctional composite aerogel is filled between conductor with insulating layer and cable outer skin.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of cables, and particularly relates to a high-performance multifunctional cable and a preparation method thereof. BACKGROUND

[0002] With the rapid development of new energy, special industry, aerospace and ocean exploration fields, unprecedentedly high requirements are put forward for the performance of cables applied in extremely harsh environments. These cables not only need to ensure stable power and signal transmission, but also need to have excellent comprehensive protection capabilities such as high-temperature resistance, flame resistance, waterproof and ice resistance, wear resistance and chemical corrosion resistance under multiple complex factors such as high temperature, open flame, humidity, icing, mechanical wear and chemical corrosion. However, the high-performance cables in the prior art still have many technical bottlenecks that are difficult to overcome.

[0003] At present, the technical solutions in the market to meet the above-mentioned needs mostly adopt the traditional material superposition and structure design idea, and the typical methods and inherent defects include: in terms of heat insulation and flame resistance, mica tape, glass fiber woven tape or halogen-free flame-retardant tape (such as polyimide tape) are generally used for multi-layer wrapping as a heat insulation and flame resistance layer. Although such materials have certain effects, their thermal conductivity coefficients are relatively high (usually > 0.05 W / (m·K)), and the heat insulation efficiency is limited. Under continuous high temperature or open flame burning, the organic binder is easy to carbonize and fail, resulting in structural collapse, which is difficult to maintain the integrity of the line for a long time. In addition, the multi-layer wrapping structure will significantly increase the diameter, weight and rigidity of the cable, which seriously sacrifices its flexibility and convenient laying. In terms of waterproof and ice resistance, metal sheath (such as lead sheath, corrugated copper sheath) or thick polymer sheath is mainly relied on to realize physical water resistance. The metal sheath is heavy, high in cost and easy to fatigue and break, while the thick polymer sheath reduces the softness of the cable, and is easy to crack and form a weak point of waterproof in a dynamic bending and low temperature environment. Ice resistance mainly relies on the low surface energy characteristics of the sheath material, which is a passive protection strategy. The ice layer still adheres and consumes a lot of energy for external deicing. In terms of mechanical properties and durability, in order to balance multiple properties, the cable structure is often designed to be extremely complex, and there are many interfaces between layers. Under dynamic bending, twisting and other mechanical stress, the thermal expansion coefficient and elastic modulus of different materials are not matched, which easily leads to interface peeling, sheath wrinkling and other problems, affecting long-term reliability.

[0004] In recent years, aerogel, as a new type of nanoporous super-insulation material, has brought new hope to solve the above-mentioned insulation problems due to its extremely low thermal conductivity (<0.025 W / (m·K)), light weight, high specific surface area and excellent fireproof properties. In the prior art, attempts have been made to apply aerogel (mainly silica aerogel) to cables, such as filling in the inter-core gap in the form of powder or particles, or preparing a felt-like body for wrapping. However, these application methods have significant limitations: (1) The inherent brittleness of silica aerogel makes it extremely easy to pulverize and settle during the laying, installation of the cable, especially repeated dragging and bending in mobile situations, leading to a sharp decline in insulation performance and the formation of local hot spots, ultimately causing insulation failure, and the reliability cannot be guaranteed. (2) Single function and passive protection: Traditional silica-based aerogel has strong hydrophilicity, which will cause the collapse of its nanoporous structure and irreversible failure of insulation performance after contacting water, and the volume expansion may squeeze the internal conductor. Therefore, it not only cannot prevent water, but also needs an additional waterproof layer to protect it, increasing the complexity and cost of the structure. (3) Lack of integration and intelligence: Simple filling or wrapping cannot effectively synergize with other functional layers of the cable, and is only a physical "addition" rather than a structural "integration". More importantly, the existing aerogel application scheme has no sensing and responding ability at all, and is a "dumb" material that cannot monitor the mechanical strain, local overheating and other health status of the cable in real time, nor can it actively deice when icing or trigger an early warning when damaged, which cannot meet the demand for equipment state sensing and interaction in smart grids and modern industrial systems.

[0005] Therefore, those skilled in the art have been working to develop a truly multifunctional and integrated high-performance cable. The core difficulty lies in how to create a new material that not only has ultra-light, ultra-insulation and high flexibility, but also deeply integrates with its waterproofness, active deicing ability and intelligent sensing and warning functions, to fundamentally break through the traditional paradigm of "multi-layer stacking", "functional isolation" and "passive protection" in the prior art, and achieve the goal of high reliability, long service life and intelligent operation of the cable under extreme conditions.

[0006] Therefore, it is practical to design a high-performance multifunctional cable and a preparation method thereof. SUMMARY

[0007] The purpose of the present application is to solve the problems in the background art and provide a high-performance multifunctional cable and a preparation method thereof.

[0008] A preparation method of a high-performance multifunctional cable, comprising the following steps:

[0009] Step one: fix the nickel-titanium wire on the pre-stretching clamp, uniformly stretch to generate 4% strain, and then evenly coat an insulating layer on the surface to obtain a shape memory alloy wire. The treated shape memory alloy wire is tightly fixed at the center position of the inner cavity of a polytetrafluoroethylene mold;

[0010] Step two: mix the phenolic resin prepolymer solution containing thermochromic microcapsules, MXene / ethanol dispersion, and silica sol according to a mass ratio of 1:1:1 to obtain a mixed sol. Slowly add ammonia water to accurately adjust the pH value of the mixed sol to 7.5. After stirring, a multifunctional composite sol is obtained.

[0011] Step three: inject the multifunctional composite sol into the polytetrafluoroethylene mold with the fixed shape memory alloy wire, seal the cover plate, and then perform gelation and modification to obtain a modified multifunctional composite gel.

[0012] Step four: sequentially immerse the modified multifunctional composite gel in anhydrous ethanol and n-hexane to replace the modifier in the pores of the modified multifunctional composite gel. Then, perform supercritical CO2 drying to obtain a multifunctional composite aerogel.

[0013] Step five: fill the multifunctional composite aerogel between the conductor with an insulating layer and the cable outer skin to form a multifunctional composite aerogel layer.

[0014] Preferably, in step one, the diameter of the nickel-titanium wire is 100 μm, and the insulating layer is polyimide varnish. After coating the polyimide varnish on the outer surface of the nickel-titanium wire, it is placed in an 80℃ oven for 1 hour to solidify. An insulating layer will be formed on the outer surface of the nickel-titanium wire.

[0015] Preferably, in step two, the preparation method of the phenolic resin prepolymer solution containing thermochromic microcapsules is as follows: mix resorcinol and formaldehyde in a molar ratio of 1:2 in deionized water, use sodium carbonate as a catalyst, and react at 60℃ for 4 hours to obtain a phenolic resin prepolymer solution with a solid content of 20%. In the phenolic resin prepolymer solution, add 1 wt% of thermochromic microcapsules corresponding to the solid mass of the phenolic resin, and stir uniformly to obtain a phenolic resin prepolymer solution containing thermochromic microcapsules.

[0016] Preferably, in step two, the thermochromic microcapsules are prepared by mixing an oil phase mixture and an aqueous phase mixture, wherein the oil phase mixture is prepared by mixing 5 wt% crystal violet lactone, 25 wt% bisphenol A or octadecyl phosphonic acid and 70 wt% tetradecyl alcohol or hexadecyl alcohol or a mixture of both, heating and melting at 85°C, and stirring to form a homogeneous liquid oil phase mixture; the aqueous phase mixture is prepared by adding deionized water and 10 wt% water-soluble polymer into a beaker, stirring to dissolve and obtain an aqueous phase mixture; the oil phase mixture is added into the aqueous phase mixture under shearing at 10,000 rpm for 5-10 minutes to form a stable oil-in-water emulsion; the pH value of the emulsion is adjusted to an acidic range of 3.5-4.5 using a citric acid or sodium acetate solution; 5 wt% melamine-formaldehyde prepolymer is slowly added; after stirring, the reaction is carried out at 60-70°C for 1 hour; the melamine-formaldehyde prepolymer gradually crosslinks, solidifies and precipitates from the aqueous phase mixture and deposits on the surface of the oil phase emulsion droplets to form a transparent wall shell; the temperature is gradually increased to 80-85°C, and the reaction is continued for 1-2 hours to completely solidify and harden the wall shell; after the reaction is completed, the reaction mixture is cooled to room temperature, and the microcapsule product is collected by filtration, washed repeatedly with deionized water and ethanol until the filtrate is neutral and clear, and the microcapsule product is vacuum dried at 40°C to obtain white thermochromic microcapsule powder.

[0017] Preferably, in step two, the MXene / ethanol dispersion is prepared by vacuum filtration of the MXene aqueous dispersion into a film, and then redispersion in anhydrous ethanol and probe sonication to obtain a stable MXene / ethanol dispersion.

[0018] Preferably, in step two, the silica sol is prepared by mixing tetraethyl orthosilicate, anhydrous ethanol and deionized water in a molar ratio of 1:4:4, adding HCl to adjust the pH to 3.0, and stirring at 40°C for 2 hours to obtain a clear silica sol.

[0019] Preferably, in step three, the gelation and modification process is as follows: the polytetrafluoroethylene mold filled with the multifunctional composite sol is placed in a 60°C air-drying oven and left to stand for 6 hours to complete the gelation process and obtain a multifunctional composite wet gel; the multifunctional composite wet gel is immersed in sufficient anhydrous ethanol together with the polytetrafluoroethylene mold, soaked at room temperature for 24 hours, and the anhydrous ethanol is replaced 3 times during the soaking; the aging process is completed, and finally the aged multifunctional composite wet gel is transferred to a perfluorodecyltriethoxysilane / ethanol solution and soaked at 50°C for 48 hours to complete the hydrophobic modification.

[0020] Preferably, in step four: the supercritical CO2 drying process is as follows: the modified multifunctional composite gel is placed in a supercritical drying kettle, liquid CO2 is introduced, and the temperature is kept at 10 DEG C and the pressure is kept at 6 MPa for 2 hours, then the temperature is increased to 50 DEG C at a rate of 0.5 DEG C / min, the pressure is increased to 12 MPa at a rate of 1 MPa / min, and the state is kept for 3 hours, finally, the pressure is released to normal pressure at a rate of <=0.1 MPa / min at 50 DEG C.

[0021] A high-performance multifunctional cable is prepared by a method for preparing a high-performance multifunctional cable.

[0022] The present application has the following advantages:

[0023] The present application realizes the functional transition from passive protection to active sensing and response, greatly improves the intelligence and safety of the cable, and successfully integrates a synergistic system composed of a MXene nanonetwork and a shape memory alloy wire in the multifunctional composite aerogel, so that the material itself has the functions of "nerves" and "muscles". The cable can realize real-time and distributed sensing of its own strain (such as bending and extrusion) and temperature (such as local overheating) changes, and output through electrical signals, realizing online monitoring of the health status of the cable. In an icing environment, the cable can start efficient and low-energy-consumption electric heating deicing through active energization, changing passive defense to active threat elimination. When the material appears microcracks due to fatigue, the shape memory alloy wire can also provide driving force under overheating conditions, realizing self-repairing of the cracks. This completely changes the "dumb" and "passive" characteristics of traditional cable aerogels, and provides a revolutionary solution for the safe operation of key lines.

[0024] Through multi-scale structure design and composite synergy, excellent mechanical properties and extreme environmental tolerance are realized, solving the long-standing performance contradiction. The present application solves the bottleneck of traditional aerogels in terms of force performance and functionality at the molecular and micro levels by constructing a phenolic resin / silica double network skeleton, introducing MXene two-dimensional nanosheets for reinforcement, and in-situ fluorination modification, so that the aerogel not only maintains the core advantages of ultra-low density (~0.20 g / cm³) and ultra-low thermal conductivity (<0.023 W / m·K), but also has high flexibility (bendable), high compression strength and superhydrophobicity. This means that the cable has excellent heat insulation and insulation capacity, and the mechanical damage resistance is greatly improved, and has intrinsic and durable waterproof and ice-proof ability, which solves the technical problems of "light and thin cannot be strong" and "heat insulation cannot be waterproof" in traditional solutions, and significantly prolongs the service life of the cable in complex working conditions.

[0025] Highly integrated functionality simplifies cable structure and reduces overall system cost and energy consumption. This invention creatively integrates multiple functions such as heat insulation, flame retardancy, waterproofing, sensing, heating, and early warning into a single aerogel layer. This simplifies the design of multi-layered shielding structures in cables, avoiding the use of separate sensors, heating wires, and heavy waterproof metal sheaths. This reduces the overall weight and volume of the cable, improving the ease of installation and applicability. Furthermore, the electrothermal de-icing system based on MXene and shape memory alloy wires boasts high thermal efficiency, and the visual early warning mechanism (thermochromic) requires no external power supply. From a life-cycle perspective, this significantly reduces the operating and maintenance costs of the cable. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the cross-section of the high-performance multifunctional cable in this invention;

[0027] Figure 2 This is a schematic diagram of the shape memory alloy wire in this invention;

[0028] Figure 3 This is a flowchart illustrating the preparation process of the multifunctional composite aerogel in this invention.

[0029] In the picture:

[0030] 1: Shape memory alloy wire; 111: Nickel-titanium wire; 112: Insulation layer; 2: Phenolic resin prepolymer solution; 3: Thermochromic microcapsules; 4: MXene / ethanol dispersion; 5: Silica sol; 6: Ammonia water; 7: Multifunctional composite sol; 8: Polytetrafluoroethylene mold; 9: Modified multifunctional composite gel; 10: Anhydrous ethanol; 11: n-Hexane; 12: Multifunctional composite aerogel; 13: Cable; 131: Conductor; 132: Insulating outer layer; 133: Multifunctional composite aerogel layer; 134: Shielding layer; 135: Protective layer. Detailed Implementation

[0031] To better illustrate the preparation process involved in this invention and its advantages over the prior art, further explanation will be provided with reference to the accompanying drawings.

[0032] As shown in the attached figure, a method for manufacturing a high-performance multifunctional cable includes the following steps:

[0033] Step 1: As Figure 2 As shown, the pretreatment of shape memory alloy wire 1 is as follows: nickel-titanium wire 111 is fixed on a pre-stretching fixture and stretched at a uniform speed until a strain of 4% is generated. After uniformly coating an insulating layer 112 on its surface, shape memory alloy wire 1 is obtained. The treated shape memory alloy wire 1 is tightened and fixed in the center of the inner cavity of the polytetrafluoroethylene mold 8.

[0034] Step Two: As Figure 3As shown, a mixed sol is obtained by mixing phenolic resin prepolymer solution 2 containing thermochromic microcapsules 3, MXene / ethanol dispersion 4, and silica sol 5 in a mass ratio of 1:1:1. Ammonia water 6 with a volume fraction of 15%-28% is slowly added dropwise until the pH value of the mixed sol is precisely adjusted to 7.5. After gently stirring for 5 minutes, a multifunctional composite sol 7 is obtained.

[0035] Step 3: Inject the multifunctional composite sol 7 into the polytetrafluoroethylene mold 8 in which the shape memory alloy wire 1 has been fixed, seal the cover plate, and after gelation and modification, obtain the modified multifunctional composite gel 9.

[0036] Step 4: The modified multifunctional composite gel 9 is soaked in anhydrous ethanol 10 and n-hexane 11 for 12 hours each to completely displace the modifier in the pores of the modified multifunctional composite gel 9, and then dried by supercritical CO2 to obtain multifunctional composite aerogel 12.

[0037] Step 5: As Figure 1 As shown, a multifunctional composite aerogel 12 is filled between an insulating conductor and a cable sheath to form a multifunctional composite aerogel layer 133. The cable sheath includes a shielding layer 134 and a protective layer 135. The insulating conductor includes a conductor 131 and an insulating outer layer 132 covering the outer surface of the conductor 131.

[0038] Preferably, in step one, the nickel-titanium wire 111 has a diameter of 100 μm, and the insulating layer 112 is a polyimide varnish. After the polyimide varnish is coated on the outer surface of the nickel-titanium wire 111, it is placed in an oven at 80°C for 1 hour to cure, at which time the insulating layer 112 is formed on the outer surface of the nickel-titanium wire 111.

[0039] Preferably, in step two, the preparation method of the phenolic resin prepolymer solution 2 containing thermochromic microcapsules 3 is as follows: resorcinol and formaldehyde are mixed in deionized water at a molar ratio of 1:2, and sodium carbonate is used as a catalyst to react at 60°C for 4 hours to obtain a phenolic resin prepolymer solution 2 with a solid content of 20%. In the phenolic resin prepolymer solution 2, thermochromic microcapsules 3 equivalent to 1 wt% of the solid mass of phenolic resin are added, and the mixture is stirred evenly to obtain the phenolic resin prepolymer solution 2 containing thermochromic microcapsules 3.

[0040] Preferably, in step two, the thermochromic microcapsule 3 is composed of an oil phase mixture (core material) and an aqueous phase mixture, wherein the oil phase mixture is prepared by mixing 5wt% crystal violet lactone, 25wt% bisphenol A or octadecyl phosphonic acid and 70wt% tetradecyl alcohol or hexadecyl alcohol or a mixture of both, heating to melt at 85°C, and stirring to form a uniform liquid oil phase mixture; the aqueous phase mixture is prepared by adding deionized water, 10wt% water-soluble polymer (such as gum arabic or styrene-maleic anhydride copolymer as emulsifier and stabilizer) in a beaker, stirring to dissolve to obtain an aqueous phase mixture; the oil phase mixture is slowly added to the aqueous phase mixture under high shear (10,000 rpm), and the shearing is continued for 5-10 minutes to form a stable oil-in-water (O / W) emulsion, the droplet size of the emulsion determines the particle size of the final microcapsule (usually 5-20 μm), then the pH of the emulsion is adjusted to an acidic range of 3.5-4.5 with a citric acid or sodium acetate solution, and then 5wt% melamine-formaldehyde prepolymer is slowly added, and the reaction is carried out at 60-70°C for 1 hour under moderate stirring, under acidic conditions and heating, the melamine-formaldehyde prepolymer gradually crosslinks and solidifies, its hydrophobicity increases, it precipitates from the aqueous phase mixture and deposits on the surface of the oil phase emulsion droplets, forming a transparent wall shell, then the temperature is gradually increased to 80-85°C, and the reaction is continued for 1-2 hours to completely solidify the wall shell, after the reaction is completed, the product is cooled to room temperature, filtered to collect the microcapsule product, and washed repeatedly with deionized water and ethanol until the filtrate is neutral and clear to remove all unreacted monomers and emulsifiers, and finally the microcapsule product is vacuum dried at 40°C to obtain white thermochromic microcapsule 3 powder.

[0041] Preferably, in step two, the MXene / ethanol dispersion 4 is prepared by vacuum filtration of the MXene aqueous dispersion (5mg / mL) into a film, and then redispersed in anhydrous ethanol and treated by probe sonication (300W, 2h) to obtain a stable MXene / ethanol dispersion 4 (concentration ~2.5mg / mL).

[0042] Preferably, in step two, the silica sol 5 is prepared by mixing tetraethyl orthosilicate, anhydrous ethanol and deionized water in a molar ratio of 1:4:4, adding 0.1mol HCl to adjust the pH to 3.0, and stirring at 40°C for 2 hours to obtain a clear silica sol 5.

[0043] Preferably, in step three, the gelation and modification process is as follows: the polytetrafluoroethylene mold 8 filled with the multifunctional composite sol 7 is placed in a 60°C air-drying oven and left to stand for 6 hours to complete the gelation process and obtain a multifunctional composite wet gel. Then the multifunctional composite wet gel is immersed in sufficient anhydrous ethanol, and soaked at room temperature for 24 hours, during which the anhydrous ethanol is replaced 3 times to complete the aging process. Finally, the aged multifunctional composite wet gel is transferred to a 1wt% perfluorodecyltriethoxysilane / ethanol solution and soaked at 50°C for 48 hours to complete the hydrophobic modification and obtain the modified multifunctional composite gel 9.

[0044] Preferably, in step four, the supercritical CO2 drying process is as follows: the modified multifunctional composite gel 9 is placed in a supercritical drying kettle, liquid CO2 is introduced, and the temperature is maintained at 10°C and the pressure at 6 MPa for 2 hours. Then the temperature is increased to 50°C at a rate of 0.5°C / min, the pressure is increased to 12 MPa at a rate of 1 MPa / min, and the state is maintained for 3 hours. Finally, the pressure is released to atmospheric pressure at a very slow rate (≤0.1 MPa / min) at 50°C, and the multifunctional composite aerogel 12 is obtained after cooling to room temperature.

[0045] Preferably, in step five, the cable 13 consists of a conductor 131, an insulating outer layer 132, a multifunctional composite aerogel layer 133, a shielding layer 134, and a protective layer 135. The conductor 131 is a twisted bundle of oxygen-free bare copper wires with a cross-sectional area of 1.5-4.0 mm². The insulating outer layer 132 is cross-linked polyethylene or silicone rubber with a thickness of 0.8-1.2 mm. The shielding layer 134 is a tinned copper wire woven shield (density ≥ 85%). The protective layer 135 is a fluoroplastic coating with a thickness of 0.5 mm.

[0046] The multifunctional composite aerogel layer 133 is constructed by building an organic (phenolic resin)-inorganic (silica) interpenetrating network, using the toughness of phenolic resin to compensate for the brittleness of silica, to obtain flexible aerogel that can bend and resist compression. Further, on the basis of the phenolic resin / silica double network, a third-phase nanomaterial MXene (Ti3C2T X ) with special functions is introduced to build a three-level interpenetrating network structure, and MXene is used for photothermal deicing due to its extremely high light-to-heat conversion efficiency. In addition, the pre-stretched nickel-titanium wire 111 serves as a macroscopic heating element and a driving element. When electrified, it can quickly heat up for deicing. When the temperature exceeds its austenite transformation starting temperature (A sWhen the temperature of the cable 13 exceeds the temperature of the thermochromic microcapsule 3, the thermochromic microcapsule 3 will change color irreversibly, providing a visual warning. This provides a valuable early warning window and enables a transition from passive protection to active early warning, solving the technical problem of how to achieve a power-free, advanced, and intuitive fire hazard warning.

[0047] During the aging stage of the gel, perfluorodecyltriethoxysilane is introduced for in-situ surface modification instead of post-spraying, so that the aerogel skeleton obtains durable and uniform super-hydrophobic properties, enhancing its inherent water and ice repellency.

Claims

1. A method of manufacturing a high performance multi-functional cable, characterized by: The method comprises the following steps: Step one: fix the nickel-titanium wire (111) on a pre-stretching clamp, uniformly stretch to generate 4% strain, and obtain a shape memory alloy wire (1) after uniformly coating an insulation layer (112) on the surface. The treated shape memory alloy wire (1) is tightly fixed at the center position of the inner cavity of a polytetrafluoroethylene mold (8); Step two: mix phenolic resin prepolymer solution (2) containing thermochromic microcapsules (3), MXene / ethanol dispersion (4) and silica sol (5) to obtain a mixed sol according to a mass ratio of 1:1:1, slowly add ammonia water (6) to accurately adjust the pH value of the mixed sol to 7.5, and obtain a multifunctional composite sol (7) after stirring; Step three: inject the multifunctional composite sol (7) into the polytetrafluoroethylene mold (8) in which the shape memory alloy wire (1) is fixed, seal the cover plate, and obtain a modified multifunctional composite gel (9) after gelation and modification; Step four: sequentially immerse the modified multifunctional composite gel (9) in anhydrous ethanol (10) and n-hexane (11) to replace the modifier in the pores of the modified multifunctional composite gel (9), perform supercritical CO2 drying, and obtain a multifunctional composite aerogel (12); Step five: fill the multifunctional composite aerogel (12) between the conductor with an insulation layer and the cable outer skin to form a multifunctional composite aerogel layer (133).

2. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step one, the diameter of the nickel-titanium wire (111) is 100 μm, and the insulation layer (112) is polyimide varnish. After coating the polyimide varnish on the outer surface of the nickel-titanium wire (111), it is placed in an 80°C oven for 1 hour. The outer surface of the nickel-titanium wire (111) will form an insulation layer (112).

3. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step two, the preparation method of the phenolic resin prepolymer solution (2) containing thermochromic microcapsules (3) is as follows: mix resorcinol and formaldehyde in a molar ratio of 1:2 in deionized water, use sodium carbonate as a catalyst, and react at 60°C for 4 hours to obtain a phenolic resin prepolymer solution (2) with a solid content of 20%. In the phenolic resin prepolymer solution (2), add thermochromic microcapsules (3) equivalent to 1 wt% of the solid mass of the phenolic resin, and stir uniformly to obtain a phenolic resin prepolymer solution (2) containing thermochromic microcapsules (3).

4. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step two, the thermochromic microcapsule (3) is composed of an oil phase mixture and an aqueous phase mixture. The preparation method of the oil phase mixture is as follows: 5wt% crystal violet lactone, 25wt% bisphenol A or octadecyl phosphonic acid, and 70wt% tetradecyl alcohol or hexadecyl alcohol or a mixture of the two are mixed and heated to melt at 85°C, and stirred to form a uniform liquid oil phase mixture; the preparation method of the aqueous phase mixture is as follows: deionized water and 10wt% water-soluble polymer are added to a beaker and stirred to dissolve to obtain an aqueous phase mixture; the oil phase mixture is added to the aqueous phase mixture under shearing at 10,000 rpm for 5-10 minutes to form a stable oil-in-water emulsion; the pH value of the emulsion is adjusted to an acidic range of 3.5-4.5 with a citric acid or sodium acetate solution; 5wt% melamine-formaldehyde prepolymer is slowly added; after stirring, the reaction is carried out at 60-70°C for 1 hour; the melamine-formaldehyde prepolymer gradually crosslinks and solidifies and precipitates from the aqueous phase mixture and deposits on the surface of the oil phase emulsion droplets to form a transparent wall shell; the temperature is gradually increased to 80-85°C; the reaction is continued for 1-2 hours to completely solidify and harden the wall shell; after the reaction is completed, the reaction system is cooled to room temperature; the microcapsule product is collected by filtration; the microcapsule product is repeatedly washed with deionized water and ethanol until the filtrate is neutral and clear; the microcapsule product is vacuum dried at 40°C to obtain white thermochromic microcapsule (3) powder.

5. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step two, the preparation method of the MXene / ethanol dispersion (4) is as follows: the MXene aqueous dispersion is vacuum filtered into a film, and then redispersed in anhydrous ethanol and treated by probe ultrasonic to obtain a stable MXene / ethanol dispersion (4).

6. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step two, the preparation method of the silica sol (5) is as follows: tetraethyl orthosilicate, anhydrous ethanol, and deionized water are mixed in a molar ratio of 1:4:4; HCl is added dropwise to adjust the pH to 3.0; and the mixture is stirred at 40°C for 2 hours to obtain a clear silica sol (5).

7. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step three, the gelation and modification process is as follows: the polytetrafluoroethylene mold (8) into which the multifunctional composite sol (7) is injected is placed in a 60°C air-drying oven and left to stand for 6 hours to complete the gelation process and obtain a multifunctional composite wet gel; the multifunctional composite wet gel is immersed in sufficient anhydrous ethanol together with the polytetrafluoroethylene mold (8) and soaked at room temperature for 24 hours, during which the anhydrous ethanol is replaced 3 times to complete the aging process; finally, the aged multifunctional composite wet gel is transferred to a perfluorodecyltriethoxysilane / ethanol solution and soaked at 50°C for 48 hours to complete the hydrophobic modification.

8. The method for preparing a high-performance multifunctional cable according to claim 1, characterized in that: In step four, the supercritical CO2 drying process is as follows: the modified multifunctional composite gel (9) is placed in a supercritical drying kettle, liquid CO2 is introduced, and the temperature is maintained at 10°C and the pressure is maintained at 6 MPa for 2 hours; then the temperature is increased to 50°C at a rate of 0.5°C / min, the pressure is increased to 12 MPa at a rate of 1 MPa / min, and the state is maintained for 3 hours; finally, the pressure is released to atmospheric pressure at a rate of ≤0.1 MPa / min at 50°C.

9. A high performance multi-functional cable characterized by: The high-performance multifunctional cable is prepared by any one of the preparation methods of claims 1-8.

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