Conductive temperature-regulating nanofiber core-spun yarn and preparation method thereof

Abstract

The invention provides a preparation method of a conductive temperature-regulating nanofiber core-spun yarn. The preparation method comprises the following steps: (1) preparing a composite nanofiber yarn with a skin-core structure; (2) preparing the phase change fasciated yarn; (3) preparing a chemical plating solution; (4) preparing conductive cotton yarns; and (5) preparing the conductive temperature-adjusting nanofiber core-spun yarn. The core spun yarn prepared by the invention has excellent conductivity and temperature regulation performance, and has wide application prospects in the fields of wearable electronic equipment, intelligent textiles, medical care and environmental protection.

Description

Technical Field

[0001] The present invention belongs to the technical field of core-spun yarns, and particularly relates to a conductive temperature-regulating nanofiber core-spun yarn and a preparation method thereof. Background Art

[0002] With the progress of technology and the development of the textile industry, multifunctional composite fibers have gradually become a research hotspot. Wrap yarn, also known as parallel yarn and covered yarn, is a fancy yarn with a twistless sliver as the core and a filament or yarn wrapped around it. It is spun using a "hollow spindle". The short fiber sliver or roving enters the hollow spindle after passing through the drafting device. The filament bobbin is sleeved outside the hollow spindle and rotates at the same speed as it. The unwound filament converges with the drafted sliver and then enters the hollow spindle together. At the convergence point, the sliver is wrapped to form a wrap yarn. Core-spun yarn is a new type of yarn composed of two or more types of fibers. Compared with traditional yarns, core-spun yarns have the excellent properties of both the core filament and the outer short fibers. By selecting different nanofiber materials, conductive components, and adjusting the preparation process, etc., core-spun yarns with specific functions can be customized.

[0003] Organic phase change materials, as a class of efficient thermal energy storage media, exhibit excellent performance and have great potential in the fields of thermal energy storage and waste heat recovery and conversion. However, the inherent drawback of easy leakage during the solid-liquid conversion restricts their wide application. With the in-depth research, electrospinning technology has been innovatively applied to prepare phase change temperature control fibers, realizing the ingenious combination of phase change materials and polymer matrices. This method can either directly incorporate the phase change materials into the polymer solution for co-blending spinning or, through the advanced technology of coaxial electrospinning, construct a unique skin-core structure fiber membrane for phase change materials with poor compatibility with polymers. This structural design not only ensures the efficient encapsulation of phase change materials but also enhances the overall performance and stability of the fibers, opening up a new path for the wide application of phase change materials in the textile and other fields. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a conductive temperature-regulating nanofiber core-spun yarn. As a new type of multifunctional composite fiber, it has both conductive and temperature-regulating functions, is suitable for cold regions in winter, and can also be used in smart textiles, solving the technical problems related to temperature regulation and conductivity in the field of wearable electronic devices for existing textiles.

[0005] The first object of the present invention is to provide a preparation method of a conductive temperature-regulating nanofiber core-spun yarn, including the following steps:

[0006] (1) Preparation of a composite nanofiber yarn with a core-shell structure

[0007] Disperse the nano-thermal conductive filler and the polymer uniformly in an organic solvent to obtain a skin layer solution; heat and dissolve the organic phase change material to obtain a core layer solution; perform coaxial electrospinning on the skin layer solution and the core layer solution to obtain a composite nanofiber yarn with a skin-core structure;

[0008] (2) Preparation of phase change wrapped yarn

[0009] Wind the polyethylene terephthalate filament around the composite nanofiber yarn with a skin-core structure obtained in step (1) to obtain a phase change wrapped yarn;

[0010] (3) Preparation of electroless plating solution

[0011] Prepare an electroless plating solution of copper, nickel, silver, zinc or tin metal ions;

[0012] (4) Preparation of conductive cotton yarn

[0013] The cotton yarn modified by plant polyphenols is successively subjected to complexation, reduction, and electroless plating to obtain conductive cotton yarn;

[0014] (5) Preparation of conductive temperature-regulating nanofiber core-spun yarn

[0015] Feed the conductive cotton yarn prepared in step (4) into a jet vortex spinning machine, and the phase change wrapped yarn prepared in step (2) is fed through a yarn guiding device at the spacing between the first roller and the second roller for jet vortex spinning to obtain a conductive temperature-regulating nanofiber core-spun yarn with the phase change wrapped yarn as the core layer and the conductive cotton yarn as the outer layer.

[0016] Preferably, in step (1), the nano-thermal conductive filler includes one of nano-SiO 2 , Al 2 O 3 or BN; the dosage of the nano-thermal conductive filler is 0.1-6 wt% of the mass of the polymer; preferably, the nano-thermal conductive filler is BN.

[0017] Preferably, in step (1), the polymer includes one of polyacrylonitrile, polyvinylidene fluoride, polyurethane, polyamide or polyimide; the mass percentage content of the polymer in the skin layer solution is 5-20 wt%; preferably, the polymer is polyacrylonitrile.

[0018] Preferably, in step (1), the organic phase change material is polyethylene glycol (PEG); preferably, the organic phase change material is polyethylene glycol with a number average molecular weight of 800-1500, and most preferably, the organic phase change material is polyethylene glycol with a number average molecular weight of 1500.

[0019] Preferably, in step (1), the spinning voltage during coaxial electrospinning is 10 - 20 kV; preferably, the spinning voltage is 15 kV.

[0020] Preferably, the process parameters of the coaxial electrospinning further include: temperature 30 - 60 °C, humidity 20 - 50%, core layer solution feeding rate 0.005 - 0.5 mL / h, skin layer solution feeding rate 0.05 - 5 mL / h, receiving distance 12 - 40 cm.

[0021] Preferably, in step (2), the winding includes single-layer winding and spiral winding; preferably, the winding is single-layer winding.

[0022] Preferably, the process parameters of the winding are: PET filament draft ratio 1.01 - 1.20 times, distance between the composite nanofiber yarn and the PET filament 0.1 - 10 mm, yarn twist coefficient 100 - 800, filament feeding ratio 0.2 - 1.0; preferably, the filament feeding ratio is 0.9 - 1.0.

[0023] Preferably, in step (3), the concentration of metal ions in the electroless plating solution is 0.02 - 0.3 mol / L.

[0024] Preferably, the specific preparation method of the electroless plating solution is: dissolving 0.02 - 0.3 mol / L of copper sulfate hexahydrate / nickel sulfate hexahydrate / silver sulfate hexahydrate / zinc sulfate / tin sulfate, 0.1 mol / L - 1 mol / L of sodium dihydrogen phosphate, 0.05 - 0.6 mol / L of sodium citrate, and 0.5 - 2 mol / L of boric acid in deionized water, and stirring evenly to obtain.

[0025] Preferably, in step (4), the plant polyphenol is selected from tannic acid, tea polyphenol or aqueous solution of seaweed polyphenol, and the solution concentration is 5 g / L - 35 g / L.

[0026] Preferably, the modification with plant polyphenol is specifically: soaking the cotton yarn to be treated in the aqueous solution of plant polyphenol, and performing microwave-assisted treatment on the cotton yarn for 1 - 5 min.

[0027] The complexation is specifically: soaking the cotton yarn modified with plant polyphenol in a solution of 10 - 50 g / L of Ni 2+ 、Fe 3+ 、Zn 2+ or Mg 2+ for 5 - 60 min to obtain the complexed modified cotton yarn.

[0028] The reduction is specifically: treating the complexed modified cotton yarn with 0.01 - 0.5 mol / L of sodium borohydride / potassium borohydride solution for 10 s - 300 s to obtain the reduced cotton yarn.

[0029] The electroless plating specifically is as follows: The reduced cotton yarn is soaked in the electroless plating solution described in step (3) at 10 - 60 °C for 20 - 150 min.

[0030] Preferably, in step (5), the process parameters of the air-jet vortex spinning are as follows: The total draft multiple is 50 - 300 times, and the main draft multiple is 10 - 50 times; preferably, the total draft multiple is 120 - 260 times, and the main draft multiple is 21 - 35 times.

[0031] The second object of the present invention is to provide a conductive temperature-regulating core-spun yarn made by the above preparation method.

[0032] The beneficial effects of the present invention are as follows:

[0033] The present invention uses a wrapped yarn with a phase change function as the core yarn and conductive cotton fibers as the outer wrapping fibers, and is obtained by vortex spinning, having excellent temperature-regulating performance and conductive performance. The temperature-regulating performance is mainly reflected in the phase change wrapped yarn. The phase change wrapped yarn uses a polyethylene glycol (PEG) phase change material as the core layer and a polymer such as polyacrylonitrile (PAN) as the shell layer. The two are obtained by coaxial electrospinning to obtain a core-shell structured nano-composite fiber yarn, and polyethylene terephthalate (PET) filaments are wound around the nano-composite fiber yarn. In the selection of the core layer material, the phase change temperature of the PEG composite material is 36.4 °C, which is suitable for the human body temperature, and has a latent heat of 171 J·g -1 , and it is an excellent composite material for preparing intelligent temperature-regulating textiles. The shell layer materials such as PAN polymers have good mechanical properties and thermal stability, and the addition of nano-thermal conductive fillers makes the nano-fiber yarn have good thermal conductivity and faster temperature responsiveness. The conductive performance is mainly reflected in that the cotton fibers are modified by a modifier and then obtained conductive cotton fibers through complexation, reduction, and electroless plating; the modifier is selected from plant polyphenols, which can be well adsorbed on the cotton fibers, and then complexation, reduction, and electroless plating of metal ions are carried out to obtain outer wrapping cotton fibers with excellent conductive performance. The preparation method of a core-spun yarn of the present invention can continuously wrap the core yarn containing different phase change and conductive materials, thereby obtaining a core-spun yarn with temperature-regulating and conductive functions.

[0034] The core-spun yarn prepared by the present invention has excellent conductive and temperature-regulating performance, and has broad application prospects in the fields of wearable electronic devices, intelligent textiles, medical care, and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0036] Figure 1 The heating curves of nanofiber yarns with different phase change materials.

[0037] Figure 2 The cooling curves of nanofiber yarns with different phase change materials.

[0038] Figure 3 The temperature changes of nanofiber yarns with different phase change materials during 20 heating and cooling cycles.

[0039] Figure 4 SEM image of composite nanofibers containing PEG1500.

[0040] Figure 5 TEM image of composite nanofibers containing PEG1500.

[0041] Figure 6 The heating curves of different PEG nanofiber yarns.

[0042] Figure 7 The cooling curves of different PEG nanofiber yarns.

[0043] Figure 8 The heating curves of nanofiber yarns with different thermal conductive materials.

[0044] Figure 9 The cooling curves of nanofiber yarns with different thermal conductive materials.

[0045] Figure 10 The heating curves of nanofiber yarns with different voltages.

[0046] Figure 11 The cooling curves of nanofiber yarns with different voltages.

[0047] Figure 12 The structure of the phase change wrapped yarn. Among them, 1 is a composite nanofiber yarn with a core - sheath structure, and 2 is a polyethylene terephthalate (PET) filament.

[0048] Figure 13 The structure of the conductive and temperature - adjustable core - spun nanofiber yarn. Among them, 3 is a conductive cotton yarn, and 4 is a phase change wrapped yarn.

[0049] Figure 14 The heating curves of different PET winding methods.

[0050] Figure 15 The cooling curves of different PET winding methods.

[0051] Figure 16 The heating curves of fabrics made of different metal electroless core - spun yarns.

[0052] Figure 17Cooling curves of electrolessly plated core-spun yarn fabrics with different metals.

[0053] Figure 18 Heating curves of core-spun yarn fabrics with different plant polyphenols.

[0054] Figure 19 Cooling curves of core-spun yarn fabrics with different plant polyphenols. Detailed implementation manners

[0055] The following examples facilitate a better understanding of the present invention, but do not limit the present invention. The experimental methods in the following examples are all conventional methods unless otherwise specified. The test materials used in the following examples are all commercially available unless otherwise specified. In the following examples, quantitative tests are all set with three repeated experiments, and the results are averaged.

[0056] The preparation method of the conductive temperature-regulating nanofiber core-spun yarn of the present invention includes the following steps:

[0057] (1) Preparation of composite nanofiber yarn with skin-core structure

[0058] Disperse the nano-thermal conductive filler and the polymer uniformly in an organic solvent to obtain a skin layer solution; heat and dissolve the organic phase change material to obtain a core layer solution; perform coaxial electrospinning on the skin layer solution and the core layer solution to obtain a composite nanofiber yarn with a skin-core structure;

[0059] (2) Preparation of phase change wrapped yarn

[0060] Wind the polyethylene terephthalate (PET) filament around the composite nanofiber yarn with a skin-core structure in step (1) to obtain a phase change wrapped yarn;

[0061] (3) Preparation of electroless plating solution

[0062] Prepare an electroless plating solution of copper, nickel, silver, zinc or tin metal ions;

[0063] (4) Preparation of conductive cotton yarn

[0064] The cotton yarn modified with plant polyphenols is successively subjected to complexation, reduction, and electroless plating to obtain a conductive cotton yarn;

[0065] (5) Preparation of conductive temperature-regulating nanofiber core-spun yarn

[0066] Feed the conductive cotton yarn prepared in step (4) into a jet vortex spinning machine, and feed the phase change wrapped yarn prepared in step (2) through a yarn guiding device into the gap between the first roller and the second roller for jet vortex spinning to obtain a conductive temperature-regulating nanofiber core-spun yarn with the phase change wrapped yarn as the core layer and the conductive cotton yarn as the outer layer.

[0067] In some embodiments, in step (1), the nano-thermal conductive filler includes one of nano-SiO 2 , Al 2 O 3 or BN; the dosage of the nano-thermal conductive filler is 0.1-6 wt% of the mass of the polymer; preferably, the nano-thermal conductive filler is BN.

[0068] In some embodiments, in step (1), the polymer includes one of polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polyurethane (TPU), polyamide (PA) or polyimide (PI); the mass percentage content of the polymer in the skin solution is 5-20 wt%; preferably, the polymer is polyacrylonitrile.

[0069] In some embodiments, in step (1), the organic solvent is a mixed solvent of N,N-dimethylformamide (DMF) and acetone.

[0070] In some embodiments, in step (1), the specific method for preparing the skin solution is: dispersing the nano-thermal conductive filler and the polymer in the organic solvent, stirring at 50-100 °C for 3-9 h to obtain the skin solution; or first dispersing the nano-thermal conductive filler in the organic solvent, ultrasonically treating at room temperature for 2-3 h, then adding the polymer, and stirring at 50-100 °C for 3-9 h to obtain the skin solution.

[0071] In some embodiments, in step (1), the organic phase change material is polyethylene glycol (PEG); preferably, the organic phase change material is polyethylene glycol with a number average molecular weight of 800-1500, and most preferably, the organic phase change material is polyethylene glycol with a number average molecular weight of 1500, i.e., PEG1500.

[0072] In some embodiments, in step (1), the spinning voltage during coaxial electrospinning is 10-20 kV; preferably, the spinning voltage is 15 kV.

[0073] As a preferred scheme, in step (1), the process parameters of the coaxial electrospinning further include: the temperature is 30-60 °C, the humidity is 20-50%, the receiving distance is 12-40 cm, the core layer solution feeding rate is 0.005-0.5 mL / h, and the skin layer solution feeding rate is 0.05-5 mL / h.

[0074] In some embodiments, in step (2), the fiber fineness of the PET filament is 30-80 denier (D).

[0075] In some embodiments, in step (2), the winding includes single-layer winding and spiral winding; preferably, the winding is single-layer winding.

[0076] In some embodiments, in step (2), the process parameters for winding are as follows: the draft multiple of the PET filament is 1.01 - 1.20 times, the distance between the composite nanofiber yarn and the PET filament is 0.1 - 10 mm, the yarn twist coefficient is 100 - 800, and the filament feeding ratio is 0.2 - 1.0; preferably, the filament feeding ratio is 0.9 - 1.0. Within this parameter range, the yarn strength can meet the standard.

[0077] In some embodiments, in step (2), the fineness of the phase change wrapped yarn is 50 - 200 D.

[0078] In some embodiments, in step (3), the concentration of metal ions in the electroless plating solution is 0.02 - 0.3 mol / L.

[0079] In some embodiments, in step (3), when preparing the electroless plating solution, the reducing agent is sodium dihydrogen phosphate, and the concentration is 0.1 mol / L - 1 mol / L.

[0080] As a preferred embodiment, in step (3), the specific preparation method of the electroless plating solution is as follows: dissolve 0.02 - 0.3 mol / L of copper sulfate hexahydrate / nickel sulfate hexahydrate / silver sulfate hexahydrate / zinc sulfate / tin sulfate, 0.1 mol / L - 1 mol / L of sodium dihydrogen phosphate, 0.05 - 0.6 mol / L of sodium citrate, and 0.5 - 2 mol / L of boric acid in deionized water, stir evenly, and prepare different metal electroless plating solutions with a pH value of 7 - 12.

[0081] Among them, copper sulfate hexahydrate, nickel sulfate hexahydrate, silver sulfate hexahydrate, zinc sulfate, and tin sulfate are the main salts, sodium dihydrogen phosphate is the reducing agent, sodium citrate is the complexing agent, and boric acid is the buffer.

[0082] As a preferred embodiment, in step (3), prepare the electroless plating solution of copper, nickel, or silver metal ions.

[0083] In some embodiments, in step (4), the plant polyphenols are selected from tannic acid, tea polyphenols, or aqueous solution of seaweed polyphenols, and the solution concentration is 5 g / L - 35 g / L.

[0084] As a preferred embodiment, in step (4), the modification with plant polyphenols is specifically as follows: soak the cotton yarn to be treated in an aqueous solution of 5 - 35 g / L of plant polyphenols, and microwave-assisted treatment of the cotton yarn for 1 - 5 min.

[0085] In some embodiments, in step (4), the complexation is specifically as follows: soak the cotton yarn modified with plant polyphenols in 10 - 50 g / L of Ni 2+ 、Fe 3+ 、Zn 2+ or Mg 2+Soak in the solution for 5 - 60 min to obtain the complexed modified cotton yarn.

[0086] In some embodiments, in step (4), the reduction is specifically: treating the complexed modified cotton yarn with a 0.01 mol / L - 0.5 mol / L sodium borohydride / potassium borohydride solution for 10 - 300 s to obtain the reduced cotton yarn.

[0087] In some embodiments, in step (4), the electroless plating is specifically: soaking the reduced cotton yarn in the electroless plating solution described in step (3) at 10 - 60 °C for 20 - 150 min.

[0088] In some embodiments, in step (5), the process parameters of the air-jet vortex spinning are: the total draft multiple is 50 - 300 times, and the main draft multiple is 10 - 50 times; preferably, the total draft multiple is 120 - 260 times, and the main draft multiple is 21 - 35 times. The draft multiple determines the thickness and strength of the yarn. If the draft multiple is too large, the end will appear during drafting, or the yarn strength is insufficient. If the draft multiple is too small, the yarn will be too thick and the subsequent spinnability will be poor.

[0089] Example 1 Screening of Organic Phase Change Materials for the Preparation of Composite Nanofiber Yarns with Core-Sheath Structure

[0090] Selection of organic phase change materials: Paraffin, stearic acid, sodium stearate, pentaerythritol, sorbitol, polyethylene glycol (PEG), isooctyl palmitate, isodecyl neopentanoate, etc. are all good organic phase change materials. Among them, paraffin, PEG, stearic acid, palmitic acid, and isodecyl neopentanoate can be selected as phase change materials suitable for functional fabrics. In this example, n-eicosane is selected as paraffin, and polyethylene glycol with a number average molecular weight of 1500, i.e., PEG1500, is selected as PEG.

[0091] Disperse 2 g of polyacrylonitrile (PAN) in a mixed solution of 18 g of N,N-dimethylformamide (DMF) and acetone (the mass ratio of DMF to acetone is 7:3), stir at 70 °C for 6 h to make it a uniform spinning solution, and obtain a skin layer solution with a PAN concentration of 10%. Heat and dissolve the above different organic phase change materials respectively and use them as the core layer solutions for coaxial electrospinning. In an environment with a temperature of 35 °C and a humidity of 40%, set the core layer solution feeding rate to 0.25 mL / h, the skin layer solution feeding rate to 2.5 mL / h, the receiving distance to 28 cm, and the voltage to 15 kV. Prepare composite nanofiber yarns with core-sheath structure through an electrospinning machine with a spinning device.

[0092] Spread 5 g of yarn containing different organic phase change materials evenly in a polypropylene (PP) container, place it in a constant temperature and humidity chamber at 26 °C for 24 h, and then at 1 kW·m -2Under the irradiation of a xenon lamp, the temperature change within 70 s is as shown in Figure 1 Shown. Different nanofiber yarns were heated to 65 °C with a 1 kW·m -2 Xenon lamp. After stopping heating, the temperature change is as shown in Figure 2 Shown. The heating and cooling processes were repeated to investigate the stability of the phase change material. The results are shown in Figure 3 .

[0093] Figure 1 Are the heating curves of nanofiber yarns with different phase change materials.

[0094] Figure 2 Are the cooling curves of nanofiber yarns with different phase change materials.

[0095] Figure 3 Are the temperature changes of nanofiber yarns with different phase change materials during 20 heating and cooling processes.

[0096] It can be seen from Figure 1 That under the same light conditions, when stearic acid and palmitic acid are used as phase change materials, they can only rise to 64 °C and 63 °C respectively. On the one hand, this is because their thermal conductivities are relatively weak; on the other hand, at 70 s, their phase change temperatures are reached, so that their temperatures cannot continue to rise. When n-eicosane, PEG1500 and isodecyl neopentanoate are used as phase change materials, the temperature can rise to 65 °C. The temperature of n-eicosane is lower than that of PEG1500 between 40 s and 60 s, which is because at this time, it is in the phase change temperature range of n-eicosane, absorbing heat but the temperature does not rise. Isodecyl neopentanoate undergoes a phase change between 10 s and 30 s, and the temperature is higher than that of PEG1500 after 30 s.

[0097] It can be seen from Figure 2 That when stearic acid, palmitic acid and isodecyl neopentanoate are used as phase change materials, the temperature of the yarn drops rapidly. Before cooling to 6 min, the yarn has reached room temperature, indicating that it stores less heat. The cooling rates of n-eicosane and PEG1500 are slower, and during the temperature drop process, the temperature is higher than that of the other three phase change materials.

[0098] It can be seen from Figure 3 That the nanofiber containing PEG1500 phase change material has excellent cycling performance. After 20 cycles, the maximum temperature does not decrease significantly. The decrease of n-eicosane is obvious. On the one hand, this is because the stability of n-eicosane is poor, and on the other hand, it is due to leakage during the heating and cooling processes. Considering the energy storage capacity and stability, the nanofiber yarn containing PEG1500 has the best performance.

[0099] Example 2 Screening of Polyethylene Glycols with Different Molecular Weights for the Preparation of Composite Nanofiber Yarns with a Core-Shell Structure

[0100] Disperse 2 g of PAN in a mixed solution of 18 g of DMF and acetone (mass ratio of DMF to acetone is 7:3), stir at 70 °C for 6 h to form a homogeneous spinning solution, and obtain a skin layer solution with a PAN concentration of 10%. Heat and dissolve the blank component, PEG800, PEG1000, and PEG1500 respectively as the core layer solution for coaxial electrospinning. In an environment with a temperature of 35 °C and a humidity of 40%, set the core layer solution propulsion speed to 0.25 mL / h, the skin layer solution propulsion speed to 2.5 mL / h, the receiving distance to 28 cm, and the voltage to 15 kV. Prepare composite nanofiber yarns with a core-shell structure through an electrospinning machine equipped with a spinning device.

[0101] Among them, PEG800, PEG1000, and PEG1500 are polyethylene glycols with number average molecular weights of 800, 1000, and 1500 respectively.

[0102] The morphology of the nanofibers containing PEG1500 is as Figure 4 shown. It can be clearly seen from the TEM image ( Figure 5 ) that its core-shell structure. Test the temperature change during the heating and cooling processes of the specimens according to the method in Example 1, and the results are as Figure 6 and Figure 7 shown.

[0103] Figure 4 is the SEM image of the composite nanofibers containing PEG1500.

[0104] Figure 5 is the TEM image of the composite nanofibers containing PEG1500.

[0105] Figure 6 is the heating curve of different PEG nanofiber yarns.

[0106] Figure 7 is the cooling curve of different PEG nanofiber yarns.

[0107] It can be seen from Figure 4 - 7 that PEG is a good energy storage material. As the relative molecular mass of PEG increases, the phase change temperature gradually increases. Therefore, under heating conditions, the nanofiber yarn without PEG heats up the fastest; the nanofiber yarn containing PEG1500 heats up the slowest. However, when heated to 60 s, all nanofiber yarns reach the same temperature. This is because the temperature at this time exceeds the phase change temperature of PEG.

[0108] The nanofiber yarn containing PEG has a slower cooling rate, while the nanofiber yarn without PEG has a faster cooling rate. After 8 minutes, all nanofiber yarns reach room temperature. This is because PEG stores heat during the heating process and releases energy during the cooling process, slowing down the cooling rate. After all the heat is released, it gradually approaches room temperature.

[0109] Generally speaking, PEG1500 has the best energy storage property.

[0110] Screening of nano-thermal conductive fillers for the preparation of composite nanofiber yarns with a core-shell structure in Example 3

[0111] Respectively disperse 0.02 g of nano-SiO 2 , Al 2 O 3 , and BN in 18 g of a mixed solution of DMF and acetone (the mass ratio of DMF to acetone is 7:3), and ultrasonically treat at room temperature for 2 h; then add 2 g of PAN and stir at 70 °C for 6 h to mix them into a uniform spinning solution, obtaining a skin layer solution with a PAN concentration of 10%. Heat and dissolve PEG1500 to be used as the core layer solution for coaxial electrospinning. In an environment with a temperature of 35 °C and a humidity of 40%, set the core layer solution propulsion speed to 0.25 mL / h, the skin layer solution propulsion speed to 2.5 mL / h, the receiving distance to 28 cm, and the voltage to 15 kV. Prepare composite nanofiber yarns with a core-shell structure through an electrospinning machine equipped with a spinning device. Test the temperature changes during the heating and cooling processes of the specimens according to the method in Example 1, and the test results are shown in Figure 8 and Figure 9 .

[0112] Figure 8 are the heating curves of nanofiber yarns with different thermal conductive materials.

[0113] Figure 9 are the cooling curves of nanofiber yarns with different thermal conductive materials.

[0114] From Figure 8 and Figure 9 , it can be seen that the thermal conductivity coefficients of SiO 2 , Al 2 O 3 , and BN increase in turn. Therefore, under the irradiation of the same energy, within the first 3 minutes, the nanofiber yarn containing BN has the fastest temperature drop due to its good thermal conductivity, and heat can be rapidly released in a cold environment. From 2 to 6 minutes, due to the presence of PEG1500, the temperature drop slows down, but in the later stage, the nanofiber yarn containing BN reaches temperature equilibrium the fastest. In short, the nanofiber yarn containing BN can store the most heat and release heat the fastest.

[0115] Screening of Voltage in the Coaxial Electrospinning Process of Composite Nanofiber Yarns with a Core-Sheath Structure in Example 4

[0116] Disperse 2 g of PAN and 0.02 g of BN in 18 g of a mixed solution of DMF and acetone (mass ratio of DMF to acetone is 7:3), stir at 70 °C for 6 h to mix them into a uniform spinning solution, and obtain a skin layer solution with a PAN concentration of 10%. Heat and dissolve PEG1500 as the core layer solution for coaxial electrospinning. In an environment with a temperature of 35 °C and a humidity of 40%, set the core layer solution feeding rate to 0.25 mL / h, the skin layer solution feeding rate to 2.5 mL / h, the receiving distance to 28 cm, and the voltages to 12 kV, 15 kV, and 18 kV respectively. Prepare composite nanofiber yarns with a core-sheath structure through an electrospinning machine with a spinning device. Test the temperature changes during the heating and cooling processes of the specimens according to the method in Example 1, and the results are as Figure 10 、 Figure 11 and shown in Table 1.

[0117] Figure 10 is the heating curve of nanofiber yarns at different voltages.

[0118] Figure 11 is the cooling curve of nanofiber yarns at different voltages.

[0119] Table 1 Nanofiber Yarn Diameter and Core-Wall Thickness Ratio under Different Voltage Conditions

[0120] Voltage / kV 12 15 18 Average fiber diameter / nm 850 650 500 Ratio of core wall thickness 3∶1 4.5∶1 6∶1

[0121] From Figure 10 、 Figure 11As can be seen from Table 1, the voltage affects the fiber diameter, the core-wall content ratio, the BN and phase change material content (because the compositions of the core layer and the skin layer solutions are different, resulting in different conductivities. Under the same electric field drawing, the electric field forces on the skin layer and the core layer are different, which will inevitably lead to different thicknesses of the skin layer and the core layer, that is, different core-wall contents, thus resulting in different fiber diameters and different contents of each component (conductive component BN and phase change material) (because the phase change material is in the core layer and the heat-conducting material is in the skin layer)), thereby leading to heat storage and release of the yarn. The lower the voltage, the larger the fiber diameter, the thicker the wall layer, the relatively less content of the phase change material, and the more content of the heat-conducting material. When the spinning voltage is 12 kV, the content of the heat-conducting material is the largest and the temperature is the highest during the heating process. During the cooling process, since the content of the heat-conducting material is the largest when the spinning voltage is 12 kV, the temperature drops the fastest. At 6 min, the temperature drops to room temperature. When the spinning voltage is 18 kV, the content of the heat-conducting material is less, the heating is slower, and the temperature is the lowest after 70 s. Although the cooling process is relatively slow, compared with the spinning voltage of 15 kV, there is no obvious temperature increase. This is because, although its phase change material content is relatively large and it stores more heat, it releases too much heat, and does not cause the temperature of the material itself to rise. Instead, the heat is released into the environment, resulting in heat loss. Therefore, the optimal spinning voltage is 15 kV.

[0122] Selection of Different Winding Methods for the Preparation of Conductive and Temperature-Regulating Core-Sheath Nanofiber Yarn in Example 5

[0123] The preparation method of the conductive and temperature-regulating core-sheath nanofiber yarn includes the following steps:

[0124] (1) Preparation of Composite Nanofiber Yarn 1 with Core-Sheath Structure

[0125] Prepare composite nanofiber yarn 1 with core-sheath structure (spinning voltage is 15 kV) according to the method in Example 4.

[0126] (2) Preparation of Phase Change Wrapped Yarn 4

[0127] Wrap 50 denier (50D) PET filament 2 around the composite nanofiber yarn 1 with core-sheath structure prepared in step (1) by a core-sheath yarn winding machine in two ways: single-layer winding and spiral winding. The draw ratio of the PET filament is 1.04 times, the spacing between the composite nanofiber yarn and the PET filament is 5 mm, the yarn twist coefficient is 450, and the filament feeding ratio is 0.95, thereby obtaining phase change wrapped yarn 4 with a fineness of 130D.

[0128] (3) Preparation of Electroless Plating Solution

[0129] Dissolve 25 g of nickel sulfate hexahydrate, 25 g of sodium dihydrogen phosphate, 30 g of sodium citrate, and 60 g of boric acid in deionized water, stir evenly, and prepare 1 L of nickel metal electroless plating solution with a pH value of 9.

[0130] (4) Preparation of Conductive Cotton Yarn 3

[0131] Soak the cotton yarn to be processed in a tea polyphenol aqueous solution with a concentration of 10 g / L, subject the cotton yarn to microwave-assisted treatment for 3 min, take it out, wash it three times with deionized water, and dry it to obtain tea polyphenol-modified cotton yarn; soak the tea polyphenol-modified cotton yarn in a ferric sulfate hexahydrate solution with a concentration of 20 g / L for 20 min, take it out to obtain modified cotton yarn with metal iron ions adsorbed (i.e., complexed) on the surface; reduce the modified cotton yarn with metal iron ions adsorbed on the surface with a 0.03 mol / L sodium borohydride solution for 100 s to obtain reduced cotton yarn; soak the reduced cotton yarn in an electroless nickel plating solution at 40 °C for 50 min, take it out, wash it three times with deionized water, and dry it to obtain nickel-plated conductive cotton yarn 3.

[0132] (5) Preparation of Conductive Temperature-Regulating Core-Spun Nanofibers

[0133] Feed the conductive cotton yarn 3 prepared in step (4) into a jet vortex spinning machine, and the phase change wrapped yarn 4 is fed into the gap between the first roller and the second roller through a yarn guiding device for jet vortex spinning, and a conductive temperature-regulating core-spun nanofiber with the phase change wrapped yarn 4 as the core layer and the conductive cotton yarn 3 as the outer layer can be obtained. The process parameters of jet vortex spinning are that the total draft multiple is 180 times and the main draft multiple is 26 times.

[0134] After subjecting the obtained yarn to a series of pre-weaving preparation processes such as winding, warping, sizing, and threading, a warp beam is made, and then the warp and weft yarns are interwoven on a loom according to the fabric organization rule of one up and one down through "shedding, weft insertion, beating-up, take-up, and let-off" to form a fabric. Cut the test sample into a specification of 5 cm × 5 cm, and according to the method in Example 1, test the temperature change during the heating and cooling processes of the test sample. By observing the time for the fabric to return to room temperature, its heat preservation performance is characterized. The experimental results are shown in Figure 14 and Figure 15 。

[0135] Figure 12 is the structure of the phase change wrapped yarn. Among them, 1 is a composite nanofiber yarn with a skin-core structure, and 2 is a polyethylene terephthalate (PET) filament.

[0136] Figure 13 is the structure of the conductive temperature-regulating core-spun nanofiber. Among them, 3 is the conductive cotton yarn, and 4 is the phase change wrapped yarn.

[0137] Figure 14 is the heating curve of different PET winding methods.

[0138] Figure 15 is the cooling curve of different PET winding methods.

[0139] The main winding methods of core-spun yarn include single-layer winding, double-layer winding, spiral winding, etc. Using double-layer core-spun yarn for heat storage and slow release has low efficiency. Therefore, only the heat storage and release of PET single-layer winding and spiral winding are compared. Due to the large elasticity and fluffiness of the spiral-wound yarn and the presence of an air layer, it is not easy to store and release heat. From Figure 14 and 15 It can also be seen that single-layer wound fabrics can achieve higher temperatures, and the heat is released faster during the cooling process, with better heat preservation performance. Although the spiral winding has an air layer and has good heat preservation effect, at the same time, the heat of the internal nanofiber yarn is not easy to dissipate, resulting in a lower surface temperature of the fabric. Therefore, single-layer winding has better heat storage and release performance.

[0140] Example 6 Selection of Electroless Plating Solution for the Preparation of Conductive Temperature-Regulating Nanofiber Core-Spun Yarn

[0141] In this example, the difference in the preparation method of the conductive temperature-regulating nanofiber core-spun yarn from that in Example 5 lies in:

[0142] (1) Preparation of electroless plating solution

[0143] Dissolve 25 g of copper sulfate hexahydrate / 25 g of nickel sulfate hexahydrate / 25 g of silver sulfate hexahydrate / 25 g of zinc sulfate / 25 g of stannous sulfate, 25 g of sodium dihydrogen phosphate, 30 g of sodium citrate, and 60 g of boric acid in deionized water, stir evenly, and prepare 1 L of different metal electroless plating solutions with a pH value of 9.

[0144] (2) Preparation of phase change wrapped yarn

[0145] Wrap 50D PET filaments around the nanofiber yarn containing BN in a single layer to prepare phase change wrapped yarn.

[0146] The remaining steps and parameters are the same as those in Example 5, and a series of conductive temperature-regulating nanofiber core-spun yarns are prepared.

[0147] And according to the fabric preparation method in Example 5, different metal electroless plating core-spun yarn fabrics are prepared, and the temperature changes during the heating and cooling processes of the specimens are tested. By observing the time for the fabric to return to room temperature, its heat preservation performance is characterized, and the results are as Figure 16 、 Figure 17 shown.

[0148] Figure 16 is the heating curve of different metal electroless plating core-spun yarn fabrics.

[0149] Figure 17 is the cooling curve of different metal electroless plating core-spun yarn fabrics.

[0150] Performance test:

[0151] The morphology of the nanofiber membrane was observed using a TM3000 type SEM and a JEM2100F type TEM. A circular sample with a diameter of 5 cm was placed under the irradiation of a xenon lamp (HGILX500) with a power of 1 kW·m -2 in a constant temperature and humidity environment with a temperature of 26 °C and a relative humidity of 35%. The temperature of the specimen was measured using a Tis10 type infrared thermal imager. The mechanical properties of the fabric were tested using a universal material testing machine. The sample was cut into a size of 40 mm × 10 mm, the distance between the upper and lower chucks was set to 20 mm, and the sample was stretched at a speed of 10 mm / min. Each sample was tested five times, and then the average value was taken.

[0152] According to the ASTM E96 moisture permeability test standard, the moisture vapor transmission rate (WVTR) of the sample was measured using the inverted cup method. First, three suitable specimens were cut from different positions of the same sample, and then the cut specimens were fixed in the specimen cups. Then, they were placed in a constant moisture permeability test chamber, where the temperature and humidity in the chamber were set to 38 °C and 50% RH respectively. After the experiment, the WVTR was calculated.

[0153] The formula for calculating the moisture vapor transmission rate is: WVTR = [(m1 - m2) / A] × 24, where m1 is the weight before the test, m2 is the weight after the test, and A is the test area, with the unit of kg·m -2 ·d -1 .

[0154] According to the ASTM D 737 air permeability test standard, the air permeability of the nanofiber membrane was tested using a fabric air permeability tester (YG461G). The test area was 20 cm 2 , the air pressure was 100 Pa, and each sample was tested at least 3 times.

[0155] The sheet resistance and resistivity of the sample were measured using an RTS-11 type four-probe tester. The sheet resistance and resistivity at 5 different positions of each sample were measured, and the average value was taken.

[0156] The results of the performance tests are shown in Table 2.

[0157] Table 2 Performance indexes of different electroless metal-plated core-spun yarn fabrics

[0158]

[0159] Among them, the BN nanofiber fabric in Table 2 is a composite nanofiber yarn with a skin-core structure prepared according to the method of Example 4 (the voltage in the coaxial electrospinning process is 15 kV).

[0160] The modified cotton fabric in Table 2 is a conductive cotton yarn prepared according to the method of step (4) of Example 5.

[0161] The preparation method of the PET wrapped yarn fabric in Table 2 is the conductive cotton yarn prepared by the method of step (2) of Example 5.

[0162] From Figure 16 、 Figure 17 and Table 2, it can be seen that after adding modified cotton fibers or PET wrapping to the BN nanofiber fabric, the heating rate decreases significantly, which is due to the poor heat conduction rate of cotton fibers and PET fibers. The heating rate of the copper, nickel, and silver electroless plating core-spun yarn fabrics is significantly better than that of the BN nanofiber fabric. Among them, the silver-plated core-spun yarn fabric and the copper-plated core-spun yarn fabric have the best heat conduction performance, indicating that electroless plating can significantly improve the heat conduction performance of the fabric. The heating process of the zinc-plated and tin-plated core-spun yarns has no obvious advantage over the BN nanofiber fabric, which may be due to the easy oxidation of zinc and tin during the deposition process, resulting in uneven deposition or decreased adhesion. There is also no obvious advantage for the zinc-plated and tin-plated core-spun yarns during the cooling process. Moreover, during the cooling process, due to the presence of the energy storage material PEG, low thermal conductivity materials such as cotton fibers and PET fibers, the fabric dissipates heat slowly. Therefore, the copper, nickel, and silver electroless plating core-spun yarn fabrics have excellent temperature regulation functions.

[0163] In summary, in addition to having good heat preservation function, cotton fabrics also provide excellent wearing comfort. The presence of PET not only provides heat preservation but also good mechanical properties. Electroless plating provides excellent electrical conductivity. Therefore, the fabric of the present invention not only has good temperature regulation function and is suitable for cold regions in winter, but can also be used in smart textiles, endowing winter protective articles with good intelligence.

[0164] Example 7 Selection of Complexing Agents for Conductive Cotton Yarn in the Preparation of Conductive Temperature-Regulating Nanofiber Core-Spun Yarn

[0165] In this example, the difference in the preparation method of the conductive temperature-regulating nanofiber core-spun yarn from that of Example 5 lies in:

[0166] (1) When preparing the phase change wrapped yarn 4, the winding method is single-layer winding.

[0167] (2) When preparing the conductive cotton yarn 3, the cotton yarn to be treated is respectively immersed in aqueous solutions of tannic acid, red algae polyphenol, and green algae polyphenol (both red algae and green algae polyphenols belong to seaweed polyphenols) with a concentration of 10 g / L to prepare the conductive cotton yarn 3.

[0168] The remaining steps and parameters are the same as those in Example 5, and a series of conductive temperature-regulating nanofiber core-spun yarns are prepared.

[0169] And according to the fabric preparation method in Example 5, different metal electroless plating core-spun yarn fabrics are prepared, and the temperature changes during the heating and cooling processes of the specimens are tested. By observing the time for the fabric to return to room temperature, its heat preservation performance is characterized, and the results are as Figure 18 、 Figure 19 shown.

[0170] Figure 18 The heating curve of the core-spun yarn fabric with different plant polyphenols.

[0171] Figure 19 The cooling curve of the core-spun yarn fabric with different plant polyphenols.

[0172] Tannic acid usually has a complex polymer structure and contains a large number of phenolic hydroxyl groups, which gives it strong complexing ability. In the treatment of cotton yarn, tannic acid can quickly and firmly complex metal ions on the yarn surface to form a relatively dense complex layer. Tea polyphenols mainly include components such as catechins and flavonoids. The number of phenolic hydroxyl groups is relatively less than that of tannic acid, and the complexing ability is relatively weak. The complexing abilities of red algae polyphenols and green algae polyphenols are between tannic acid and tea polyphenols. They have good complexing effects on some transition metal ions and can form complexes with certain stability on the surface of cotton yarn. From Figure 18 and Figure 19 results, there is almost no difference among tannic acid, tea polyphenols, red algae polyphenols and green algae polyphenols during the heating and cooling processes of the core-spun yarn, and the curves almost coincide, indicating that the above four substances have good ability to complex metals and subsequent electroless plating processes can be carried out.

[0173] Preparation of Conductive and Temperature-Regulating Core-Spun Nanofibers in Example 8

[0174] The preparation method of the conductive and temperature-regulating core-spun nanofibers includes the following steps:

[0175] (1) Preparation of Composite Nanofiber Yarn 1 with Skin-Core Structure

[0176] Disperse 1 g of PVDF and 0.06 g of BN in a mixed solution of 19 g of DMF and acetone (the mass ratio of DMF to acetone is 7:3), stir at 100 °C for 8 h to make it a uniform spinning solution, and obtain a skin layer solution with a PAN concentration of 5%. Heat and dissolve PEG1500 as the core layer solution for coaxial electrospinning. In an environment with a temperature of 30 °C and a humidity of 20%, set the core layer solution propulsion speed to 0.005 mL / h, the skin layer solution propulsion speed to 0.05 mL / h, the receiving distance to 12 cm, and the voltage to 15 kV. Prepare a composite nanofiber yarn with a skin-core structure through an electrospinning machine with a spinning device.

[0177] (2) Preparation of Phase-Change Wrapped Yarn 4

[0178] The 50 denier (50D) PET filaments 2 are wound around the composite nanofiber yarn 1 with a core - sheath structure prepared in step (1) by a core - spun wrapping machine in a single - layer winding manner. The draw ratio of the PET filaments is 1.01 times, the spacing between the composite nanofiber yarn and the PET filaments is 0.1 mm, the yarn twist coefficient is 100, and the filament feeding ratio is 0.2, thereby obtaining the phase - change wrapped yarn 4.

[0179] (3) Preparation of electroless plating solution

[0180] Dissolve 70 g of copper sulfate hexahydrate, 119 g of sodium dihydrogen phosphate, 150 g of sodium citrate, and 120 g of boric acid in deionized water, stir evenly, adjust the pH value of the electroless plating solution, and prepare 1 L of copper metal electroless plating solution with a pH value of 7.

[0181] (4) Preparation of conductive cotton yarn 3

[0182] Immerse the cotton yarn to be treated in a tea polyphenol aqueous solution with a concentration of 5 g / L, perform microwave - assisted treatment on the cotton yarn for 5 min, take it out, wash it three times with deionized water, and dry it to obtain the tea - polyphenol - modified cotton yarn; immerse the tea - polyphenol - modified cotton yarn in a zinc sulfate solution with a concentration of 10 g / L for 60 min, take it out to obtain the modified cotton yarn with metal zinc ions adsorbed (i.e., complexed) on the surface; reduce the modified cotton yarn with metal zinc ions adsorbed on the surface with a 0.01 mol / L potassium borohydride solution for 300 s to obtain the reduced cotton yarn; immerse the reduced cotton yarn in the electroless copper plating solution at 10 °C for 150 min, take it out, wash it three times with deionized water, and dry it to obtain the copper - plated conductive cotton yarn 3.

[0183] (5) Preparation of conductive temperature - regulating nanofiber core - spun yarn

[0184] Feed the conductive cotton yarn 3 prepared in step (4) into a jet vortex spinning machine, and the phase - change wrapped yarn 4 is fed through a yarn - guiding device into the gap between the first roller and the second roller for jet vortex spinning, thereby obtaining a conductive temperature - regulating nanofiber core - spun yarn with the phase - change wrapped yarn 4 as the core layer and the conductive cotton yarn 3 as the outer layer. The process parameters of jet vortex spinning are a total draw ratio of 300 times and a main draw ratio of 50 times.

[0185] Example 9 Preparation of conductive temperature - regulating nanofiber core - spun yarn

[0186] The preparation method of the conductive temperature - regulating nanofiber core - spun yarn includes the following steps:

[0187] (1) Preparation of composite nanofiber yarn 1 with a core - sheath structure

[0188] Disperse 4 g of PVDF and 0.004 g of BN in a mixed solution of 16 g of DMF and acetone (the mass ratio of DMF to acetone is 7:3), stir at 80 °C for 3 h to mix them into a uniform spinning solution, and obtain a skin layer solution with a PAN concentration of 20%. Heat and dissolve PEG1500 as the core layer solution for coaxial electrospinning. In an environment with a temperature of 60 °C and a humidity of 50%, set the core layer solution feeding rate to 0.5 mL / h, the skin layer solution feeding rate to 5 mL / h, the receiving distance to 40 cm, and the voltage to 15 kV. Prepare a composite nanofiber yarn with a skin-core structure through an electrospinning machine with a spinning device.

[0189] (2) Preparation of phase change wrapped yarn 4

[0190] Wind the 50 denier (50D) PET filament 2 around the composite nanofiber yarn 1 with a skin-core structure prepared in step (1) by a core-spun yarn winding machine in a single-layer winding manner, where the draw ratio of the PET filament is 1.20 times, the distance between the composite nanofiber yarn and the PET filament is 10 mm, the yarn twist coefficient is 800, and the filament feeding ratio is 1.0, thereby obtaining the phase change wrapped yarn 4.

[0191] (3) Preparation of electroless plating solution

[0192] Dissolve 9 g of silver sulfate hexahydrate, 12 g of sodium dihydrogen phosphate, 13 g of sodium citrate, and 30 g of boric acid in deionized water, stir evenly, adjust the pH value of the electroless plating solution, and prepare a silver metal electroless plating solution with a pH value of 12 in 1 L.

[0193] (4) Preparation of conductive cotton yarn 3

[0194] Soak the cotton yarn to be treated in an aqueous solution of plant tea polyphenols with a concentration of 35 g / L, perform microwave-assisted treatment on the cotton yarn for 1 min, take it out, wash it three times with deionized water, and dry it to obtain tea polyphenol-modified cotton yarn; soak the tea polyphenol-modified cotton yarn in a 50 g / L nickel sulfate hexahydrate solution for 5 min, take it out to obtain a modified cotton yarn with metal nickel ions adsorbed (i.e., complexed) on the surface; reduce the modified cotton yarn with metal nickel ions adsorbed on the surface with a 0.5 mol / L sodium borohydride solution for 10 s to obtain the reduced cotton yarn; soak the reduced cotton yarn in the electroless silver plating solution at 60 °C for 20 min, take it out, wash it three times with deionized water, and dry it to obtain the silver-plated conductive cotton yarn 3.

[0195] (5) Preparation of conductive temperature-regulating nanofiber core-spun yarn

[0196] Feed the conductive cotton yarn 3 prepared in step (4) into a jet vortex spinning machine. The phase change wrapped yarn 4 is fed into the gap between the first roller and the second roller through a yarn guiding device, and jet vortex spinning is carried out, then a conductive temperature-regulating nanofiber core-spun yarn with the phase change wrapped yarn 4 as the core layer and the conductive cotton yarn 3 as the outer layer can be obtained. The process parameters of the jet vortex spinning are that the total draft multiple is 50 times and the main draft multiple is 10 times.

[0197] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a conductive temperature-regulating nanofiber core-spun yarn, characterized in that: The following steps are involved: (1) Preparation of composite nanofiber yarn with skin-core structure The nano thermal conductive filler and the high molecular polymer are uniformly dispersed in an organic solvent to obtain a skin solution; the organic phase change material is heated and dissolved to obtain a core solution; the skin solution and the core solution are coaxially electrospun to obtain a composite nanofiber yarn with a skin-core structure; (2) Preparation of phase change wrapped yarn Winding polyethylene terephthalate filaments onto the composite nanofiber yarn with a core-skin structure in step (1) to obtain a phase change wrapped yarn; (3) Preparation of chemical plating solution Preparation of chemical plating solutions of copper, nickel, silver, zinc or tin metal ions; (4) Preparation of conductive cotton yarn Conductive cotton yarn is obtained by subjecting cotton yarn modified with plant polyphenols to complexation, reduction and chemical plating in sequence; (5) Preparation of conductive temperature-regulating nanofiber core-spun yarn The conductive cotton yarn prepared in step (4) is fed into a jet vortex spinning machine, and the phase change wrapped yarn prepared in step (2) is fed into the gap between the first roller and the second roller through a yarn guide device, and jet vortex spinning is performed to obtain a conductive temperature-regulating nanofiber core-wrapped yarn with the phase change wrapped yarn as the core layer and the conductive cotton yarn as the outer layer.

2. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (1), the nano thermally conductive filler includes one of nano SiO2, Al2O3 or BN; the amount of the nano thermally conductive filler is 0.1-6wt% of the mass of the high molecular polymer; preferably, the nano thermally conductive filler is BN.

3. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (1), the high molecular polymer includes one of polyacrylonitrile, polyvinylidene fluoride, polyurethane, polyamide or polyimide; the mass percentage of the high molecular polymer in the cortex solution is 5-20wt%; preferably, the high molecular polymer is polyacrylonitrile.

4. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (1), the organic phase change material is polyethylene glycol (PEG); preferably, the organic phase change material is polyethylene glycol with a number average molecular weight of 800-1500, and most preferably, the organic phase change material is polyethylene glycol with a number average molecular weight of 1500.

5. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (1), the spinning voltage during the coaxial electrospinning is 10-20 kV; preferably, the spinning voltage is 15 kV; Preferably, the process parameters of the coaxial electrospinning also include: temperature of 30-60°C, humidity of 20-50%, core solution advancing speed of 0.005-0.5mL / h, skin solution advancing speed of 0.05-5mL / h, and receiving distance of 12-40cm.

6. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (2), the winding includes single-layer winding and spiral winding; preferably, the winding is single-layer winding; Preferably, the winding process parameters are: PET filament drafting multiple 1.01-1.20 times, the spacing between the composite nanofiber yarn and the PET filament is 0.1-10 mm, the yarn twist coefficient is 100-800, and the filament feed ratio is 0.2-1.0; preferably, the filament feed ratio is 0.9-1.

0.

7. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (3), the concentration of metal ions in the chemical plating solution is 0.02 to 0.3 mol / L; Preferably, the specific preparation method of the chemical plating solution is: dissolve 0.02-0.3 mol / L of copper sulfate hexahydrate / nickel sulfate hexahydrate / silver sulfate hexahydrate / zinc sulfate / tin sulfate, 0.1 mol / L-1 mol / L of sodium dihydrogen phosphate, 0.05-0.6 mol / L of sodium citrate, and 0.5-2 mol / L of boric acid in deionized water, and stir evenly to obtain the solution.

8. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (4), the plant polyphenol is selected from tannic acid, tea polyphenol or seaweed polyphenol aqueous solution, and the concentration of the solution is 5g / L-35g / L; Preferably, the modification with plant polyphenols is specifically as follows: soaking the cotton yarn to be treated in a plant polyphenol aqueous solution, and subjecting the cotton yarn to microwave-assisted treatment for 1-5 minutes; The complexation is specifically as follows: the plant polyphenol modified cotton yarn is placed in 10-50g / L Ni 2+ , Fe 3+ 、Zn 2+ or Mg 2+ Soaking in the solution for 5-60 minutes to obtain the complexed modified cotton yarn; The reduction is specifically as follows: treating the modified cotton yarn after complexation with a 0.01-0.5 mol / L sodium borohydride / potassium borohydride solution for 10s-300s to obtain the reduced cotton yarn; The chemical plating is specifically as follows: the reduced cotton yarn is immersed in the chemical plating solution described in step (3) at 10-60° C. for a soaking time of 20-150 min.

9. The method for preparing a conductive temperature-regulating nanofiber core-spun yarn according to claim 1, characterized in that: In step (5), the process parameters of the jet vortex spinning are: the total drafting ratio is 50-300 times, and the main drafting ratio is 10-50 times; preferably, the total drafting ratio is 120-260 times, and the main drafting ratio is 21-35 times.

10. A conductive temperature regulating nanofiber core-spun yarn, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 9.

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