Uniform conductive spandex fiber and preparation method thereof

Abstract

The invention relates to the technical field of functional textiles, in particular to uniform conductive spandex fibers and a preparation method thereof.The preparation method comprises the steps that a conductive agent is added in the preparation process of a spandex fiber polymerization stock solution, then initial spandex fibers are obtained through dry spinning, and the particle size of the conductive agent is 50-1000 nm; the method comprises the following steps: soaking initial spandex fibers in a Fe < 3 + > aqueous solution, then soaking the initial spandex fibers in a mixed aqueous solution containing a conductive organic polymer monomer and p-toluenesulfonic acid for in-situ polymerization reaction, and drafting the initial spandex fibers in the soaking process of the mixed aqueous solution; after soaking is completed, washing, drying, stretching and shaping are conducted, and the conductive spandex fiber is obtained. Fabric prepared from the conductive spandex fiber has good antistatic performance, has great application potential in wearable intelligent fabric aspects such as healthy exercise monitoring and the like, and has wide market prospects.

Description

Technical Field

[0001] The invention relates to a uniform conductive spandex fiber and a preparation method thereof, belonging to the technical field of functional textiles. Background Art

[0002] With the rapid development of synthetic fibers, their application ratio in chemical fibers is getting higher and higher. However, synthetic fibers are prone to accumulate static electricity in practical applications. Spandex is an elastic fiber with alternating soft and hard segments, which has high resilience, excellent weather resistance and strength. At present, spandex is widely used in clothing and medical products, but it also has the problem of static electricity accumulation.

[0003] Traditional chemical fibers, natural fibers, etc. are not conductive, so it is necessary to use appropriate methods to add conductive components to improve the conductivity of the fibers. The materials currently added to conductive fibers include carbon nanomaterials, metal materials, and conductive polymer materials. Nanocarbon materials include carbon nanotubes (CNTs), carbon black (CB), and graphene oxide (GO); metal materials include silver nanowires, nanogold, and liquid metals; conductive polymer materials include polyaniline (PANl), polypyrrole (PPY), and polythiophene and derivatives (PEDOT, PSS). Among them, the addition of metal materials has the disadvantages of high cost, poor blending process, and poor fatigue resistance; while polyaniline, polypyrrole, and polythiophene are usually complexed on the fiber surface, and their water washing resistance is poor, and the resistance will gradually increase and eventually lose the antistatic effect.

[0004] The patent application with publication number CN106436288A discloses a method for preparing a conductive spandex yarn or cotton fabric, which is modified by a dopamine silane coupling agent and then added with conductive metal silver to enhance its conductivity. This method is expensive and not suitable for daily wear. The patent application with publication number CN115928256A discloses a method for preparing a low-resistance spandex fiber, which is characterized in that conductive nanoparticles are added to the spandex spinning solution, and finally a 40D low-resistance conductive fiber is prepared by dry spinning. The method has complicated steps and can resist static electricity, but the elongation elastic recovery force is poor. Summary of the invention

[0005] The present invention aims at the deficiencies of the prior art and provides a uniform conductive spandex fiber and a preparation method thereof. The spandex stock solution is modified by adding a conductive agent, and the spandex conductive fiber is obtained by dry spinning technology. The fiber is then post-treated with a conductive polymer material to further improve the conductive performance. The conductive layer and the coating layer have a coordinated effect, and the antistatic effect is greatly enhanced, so that the spandex fiber with a more excellent conductive effect is obtained, and the preparation method is simple.

[0006] The technical solution of the present invention to solve the above technical problems is as follows: a method for preparing uniform conductive spandex fiber, the preparation method comprising: S1. Preparation of initial spandex fiber: A conductive agent is added during the preparation of the spandex fiber polymerization solution, and then the initial spandex fiber is obtained by dry spinning, wherein the particle size of the conductive agent is 50nm-1000nm; S2. Post-processing operations: The initial spandex fiber was soaked in Fe 3+ aqueous solution, and then immersed in a mixed aqueous solution containing a conductive organic polymer monomer and p-toluenesulfonic acid to carry out an in-situ polymerization reaction, wherein the initial spandex fiber is subjected to a drafting operation during the immersion in the mixed aqueous solution; After the soaking is completed, the conductive spandex fiber is washed, dried, stretched and shaped to obtain the conductive spandex fiber.

[0007] Furthermore, the specific operations of step S1 are: S1.1. Under the protection of inert gas, polytetramethylene ether glycol and 4,4-diphenylmethane diisocyanate are stirred and mixed to prepare a prepolymer; S1.2, adding DMAC to the prepolymer for dilution, and then adding a chain extender and a chain terminator to obtain a chain extension solution; S1.3, adding an antioxidant, an anti-ultraviolet agent, an anti-yellowing agent and a conductive agent to the chain extension solution and stirring to obtain a modified spandex fiber polymerization stock solution; S1.4, filtering the modified spandex fiber polymerization stock solution, removing DMAC through a channel, spinning, and obtaining initial spandex fibers.

[0008] Furthermore, the chain extender is a diamine; the terminator is a monoamine; The antioxidant is at least one of BHT and BHA; The anti-ultraviolet agent is at least one of Tinuvin 328 and Tinuvin 234; The anti-yellowing agent is at least one of Tinuvin 622 and Irganox 1010; The conductive agent is at least one of single-layer carbon nanotubes, multi-layer carbon nanotubes, carbon black, and graphene oxide, and the conductive agent is used after being treated with high-pressure microfluidization.

[0009] Furthermore, in parts by weight, the ingredients include 50-75 parts of polytetramethylene ether glycol, 20-30 parts of 4,4-diphenylmethane diisocyanate, 2-5 parts of chain extender, 1-1.5 parts of chain terminator, 0.1-1 parts of antioxidant, 0.1-1 parts of anti-ultraviolet agent, 0.1-1 parts of anti-yellowing agent and 0.1-1 parts of conductive agent.

[0010] Furthermore, when preparing the prepolymer in step S1.1, the temperature is controlled to be 60-95° C. and the stirring time is 1-2 h; In step S1.2, when preparing the chain extension solution, the temperature is controlled at 5-15°C and the viscosity is controlled at 3000-6000 poise; In step S1.3, when preparing the spandex fiber polymerization stock solution, the temperature is controlled at 60-85° C. and the viscosity is controlled at 1500-3000 poise.

[0011] Furthermore, the dry spinning conditions are as follows: the inlet air temperature is 38-42°C, the upper return air temperature is 48-52°C, the spinning temperature is 226-234°C, and the spinning speed is 235-245 m / min.

[0012] Furthermore, the Fe 3+ Fe in aqueous solution 3+ The concentration is 0.05-0.6 mol / L, Fe 3+ Fe in aqueous solution 3+ The ratio of the concentration of the conductive organic polymer monomer in the mixed aqueous solution to the concentration of the conductive organic polymer monomer in the mixed aqueous solution is 1: (1-3); the ratio of the concentration of the conductive organic polymer monomer in the mixed aqueous solution to the concentration of p-toluenesulfonic acid is 1: (0.95-1.05).

[0013] Furthermore, the drafting ratio of the initial spandex fiber during the drafting operation during the soaking process of the mixed aqueous solution is 1.1-1.5; The temperature of the in-situ polymerization reaction is 0-5°C, and the reaction time is 60-240min.

[0014] Furthermore, the conductive organic polymer monomer is at least one of aniline and pyrrole; The drying temperature is 40-60° C., and the drying time is 1-3 hours.

[0015] The invention also discloses a uniform conductive spandex fiber, and the conductive spandex fiber is prepared according to the preparation method of the invention.

[0016] The beneficial effects of the present invention are: The present invention discloses a uniform conductive spandex fiber, which is prepared by adding a conductive agent to a stock solution and then polymerizing a layer of conductive polymer in situ on the outside. The conductive agent and the outer conductive polymer have a coordinated effect, which greatly enhances the antistatic effect. This allows the spandex fiber, an elastic fiber, to have high conductivity while maintaining high elongation and high resilience. The fabric made of the conductive spandex fiber of the present invention has good antistatic properties, has great application potential in wearable smart fabrics such as health and sports monitoring, and has broad market prospects.

[0017] The present invention adds a conductive agent with a suitable particle size treated by high-pressure micro-jetting during the preparation of the spandex fiber polymerization stock solution, so that the conductive agent is evenly dispersed in the spandex fiber, so that the spandex fiber maintains a good strength while the conductive agent is evenly distributed on the surface of the initial spandex fiber, which is more conducive to the in-situ polymerization of the conductive organic polymer monomer on the surface of the initial spandex fiber, and then cooperates with the appropriate drafting operation during the in-situ polymerization process to make the conductive polymer evenly and stably attached to the conductive spandex fiber. The conductive spandex fiber has excellent mechanical strength and conductive properties. The conductive polymer will not fall off after being stretched, rubbed or eroded by solvents, which significantly enhances the durability of the conductive spandex fiber. At the same time, the conductive agent added to the conductive spandex fiber cooperates with the conductive polymer layer attached to the surface, so that the conductive property of the conductive spandex fiber is more continuous, and the two have a coordinated effect to greatly enhance the antistatic effect, and can effectively improve the flexibility and recoverable deformation properties of the spandex fiber. The preparation process of the method is simple and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a microscopic morphology of the conductive spandex fiber prepared in Example 1. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is described in detail below. The present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used are only for describing specific embodiments and are not intended to limit the present invention.

[0021] A method for preparing uniform conductive spandex fiber, the preparation method comprising: S1. Preparation of initial spandex fiber: A conductive agent is added during the preparation of the spandex fiber polymerization solution, and then the initial spandex fiber is obtained by dry spinning, wherein the particle size of the conductive agent is 50nm-1000nm; S2. Post-processing operations: The initial spandex fiber was soaked in Fe 3+ aqueous solution, and then immersed in a mixed aqueous solution containing a conductive organic polymer monomer and p-toluenesulfonic acid to carry out an in-situ polymerization reaction, wherein the initial spandex fiber is subjected to a drafting operation during the immersion in the mixed aqueous solution; After the soaking is completed, the conductive spandex fiber is washed, dried, stretched and shaped to obtain the conductive spandex fiber.

[0022] Specifically, the specific operations of step S1 are: S1.1. Under the protection of inert gas, polytetramethylene ether glycol (PTMEG) and 4,4-diphenylmethane diisocyanate (MDI) are stirred and mixed to prepare a prepolymer; S1.2, adding DMAC to the prepolymer for dilution, and then adding a chain extender and a chain terminator to obtain a chain extension solution; S1.3, adding an antioxidant, an anti-ultraviolet agent, an anti-yellowing agent and a conductive agent to the chain extension solution and stirring to obtain a modified spandex fiber polymerization stock solution; S1.4, filtering the modified spandex fiber polymerization stock solution, removing DMAC through a channel, spinning, and obtaining initial spandex fibers.

[0023] Specifically, the chain extender is a diamine; the terminator is a monoamine; The antioxidant is at least one of BHT (2,6-di-tert-butyl-p-cresol) and BHA (butylated hydroxyanisole); The anti-ultraviolet agent is at least one of Tinuvin 328 and Tinuvin 234; The anti-yellowing agent is at least one of Tinuvin 622 and Irganox 1010; The conductive agent is at least one of single-layer carbon nanotubes, multi-layer carbon nanotubes, carbon black, and graphene oxide, and the conductive agent is used after being treated with high-pressure microfluidization.

[0024] More specifically, the high-pressure microfluidization treatment conditions are: conductive agent concentration of 0.5-1wt%, pressure of 100-300 MPa, temperature of 40-60°C, and 3-5 cycles.

[0025] More specifically, the diamine is selected from one or more of ethylenediamine, propylenediamine, butylenediamine, pentanediamine and isomers thereof; The monoamine is selected from one or more of diethylamine, dipropylamine, dibutylamine, cyclohexylamine and ethanolamine.

[0026] Specifically, according to the weight parts, polytetramethylene ether glycol is 50-75 parts, 4,4-diphenylmethane diisocyanate is 20-30 parts, chain extender is 2-5 parts, chain terminator is 1-1.5 parts, antioxidant is 0.1-1 parts, anti-ultraviolet agent is 0.1-1 parts, anti-yellowing agent is 0.1-1 parts, and conductive agent is 0.1-1 parts.

[0027] More specifically, the weight average molecular weight of the polytetramethylene ether glycol used in the embodiments of the present invention is 1700-2000.

[0028] Specifically, when preparing the prepolymer in step S1.1, the temperature is controlled to be 60-95° C. and the stirring time is 1-2 h; Step S1.2: When preparing the chain extension solution, the temperature is controlled at 5-15°C, and the viscosity is controlled at 3000-6000 poise (viscosity data tested at 25°C); In step S1.3, when preparing the spandex fiber polymerization stock solution, the temperature is controlled at 60-85° C., and the viscosity is controlled at 1500-3000 poise (viscosity data tested at 25° C.).

[0029] Specifically, the dry spinning conditions are: inlet air temperature is 38-42°C, upper return air temperature is 48-52°C, spinning temperature is 226-234°C, and spinning speed is 235-245 m / min.

[0030] More specifically, in the embodiment of the present invention, the initial spandex fiber prepared in step S1.4 is 40 denier yarn.

[0031] Specifically, the Fe 3+ Fe in aqueous solution 3+ The concentration is 0.05-0.6 mol / L, Fe 3+ Fe in aqueous solution 3+ The ratio of the concentration of the conductive organic polymer monomer in the mixed aqueous solution to the concentration of the conductive organic polymer monomer in the mixed aqueous solution is 1: (1-3); the ratio of the concentration of the conductive organic polymer monomer in the mixed aqueous solution to the concentration of p-toluenesulfonic acid is 1: (0.95-1.05).

[0032] To increase the conductivity of conductive organic polymers, it is necessary to make some defects in the conjugated structure of organic polymers, that is, to remove electrons from the polymer chain (oxidation) or insert electrons (reduction). This process is called doping. Therefore, the key to its conductivity lies in doping. The essence of doping is that the polymer chain with a conjugated structure undergoes charge transfer or redox reaction with the dopant. Generally, oxidizing dopants, such as metal salts (FeCl 3 ), and its doping mechanism is a charge transfer mechanism. When this dopant is used to dope a conductive polymer, the polymer chain donates or withdraws electrons, and the dopant is reduced or oxidized, and the formed dopant ions form a complex with the conductive polymer chain to maintain electrical neutrality.

[0033] Ferrous chloride (FeCl 3 ) as an oxidant to prepare polypyrrole, the reaction proceeds as follows, and a conductive polymer is formed through charge transfer.

[0034] .

[0035] Specifically, the drafting ratio of the initial spandex fiber during the drafting operation during the soaking process of the mixed aqueous solution is 1.1-1.5; The temperature of the in-situ polymerization reaction is 0-5°C, and the reaction time is 60-240min.

[0036] Specifically, the conductive organic polymer monomer is at least one of aniline and pyrrole; The drying temperature is 40-60° C., and the drying time is 1-3 hours.

[0037] A uniform conductive spandex fiber is prepared according to the preparation method of the present invention.

[0038] Example 1 S1. Preparation of initial spandex fiber: S1.1, under nitrogen protection, 50 kg of polytetramethylene ether glycol and 25 kg of diphenylmethane diisocyanate were stirred and reacted at 60°C for 1 hour to obtain prepolymer PPS; S1.2, PPS was transferred to a dissolver, 100 kg of DMAC was added, the temperature was cooled to 10°C, and it was poured into a reactor, and a mixed amine solution containing 2 kg of ethylenediamine and 1.5 kg of diethylamine was added dropwise thereto to carry out chain extension reaction and chain termination reaction to obtain a chain extension solution.

[0039] S1.3, 1kg antioxidant (BHT), 0.5kg anti-ultraviolet agent (Tinuvin 328), 0.5kg anti-yellowing agent (Tinuvin 622), 1kg conductive agent (carbon black treated with high-pressure microfluidization, 50nm-1000nm) were added to DMAC for grinding, and then added to the chain extension solution, reacted and aged at 60℃ for 8h, and then filtered to obtain the spandex fiber polymerization stock solution. DMAC was removed through the channel, and the initial spandex fiber was obtained by dry spinning; the dry spinning conditions were as follows: the inlet air temperature was 40℃, the upper return air temperature was 50℃, the spinning temperature was 230℃, and the spinning speed was 240m / min.

[0040] S2. Post-processing operations: FeCl 3 Dissolve in water to prepare a concentration of 0.05 mol / L Fe 3+ The initial spandex fiber is immersed in Fe 3+ The aqueous solution was shaken for 1 hour to allow the initial spandex fibers to absorb Fe 3+ ; Conductive organic polymer monomer (pyrrole) and p-toluenesulfonic acid were dissolved in distilled water to obtain a mixed aqueous solution, wherein the concentration of the conductive organic polymer monomer was 0.15 mol / L and the concentration of p-toluenesulfonic acid was 0.15 mol / L. 3+ The initial spandex fiber in the aqueous solution is immersed in the mixed aqueous solution at 4° C. for 1 hour to perform an in-situ polymerization reaction, and the drawing ratio during the immersion process is 1.2 times.

[0041] The fiber was washed with distilled water, dried, stretched and shaped at a temperature of 50° C. for 2 h, and finally the conductive spandex fiber was obtained.

[0042] Example 2 S1. Preparation of initial spandex fiber: S1.1, under nitrogen protection, 55 kg of polytetramethylene ether glycol and 20 kg of diphenylmethane diisocyanate were stirred and reacted at 60°C for 1 hour to obtain prepolymer PPS; S1.2, transfer PPS to a dissolver, add 100 kg of DMAC, cool the temperature to 15°C, pour it into a reactor, and drop a mixed amine solution containing 2 kg of ethylenediamine and 1 kg of diethylamine to carry out chain extension reaction and chain termination reaction to obtain a chain extension solution.

[0043] S1.3, 1kg antioxidant (BHA), 0.5kg anti-ultraviolet agent (Tinuvin 234), 0.5kg anti-yellowing agent (Irganox 1010), 0.5kg conductive agent (single-layer carbon nanotubes treated with high-pressure microfluidization, 50nm-1000nm) were added to DMAC for grinding, and then added to the chain extension solution, reacted and aged at 60℃ for 8h, and then filtered to obtain the spandex fiber polymerization stock solution. DMAC was removed through the channel, and the initial spandex fiber was obtained by dry spinning; the dry spinning conditions were as follows: the inlet air temperature was 42℃, the upper return air temperature was 52℃, the spinning temperature was 234℃, and the spinning speed was 245m / min.

[0044] S2. Post-processing operations: FeCl 3 Dissolve in water to prepare a concentration of 0.4 mol / L Fe 3+ The initial spandex fiber is immersed in Fe 3+ The aqueous solution was shaken for 1 hour to allow the initial spandex fibers to absorb Fe 3+ ; Conductive organic polymer monomer (aniline) and p-toluenesulfonic acid were dissolved in distilled water to obtain a mixed aqueous solution, wherein the concentration of the conductive organic polymer monomer was 0.4 mol / L and the concentration of p-toluenesulfonic acid was 0.6 mol / L. 3+ The initial spandex fiber in the aqueous solution is immersed in the mixed aqueous solution at 4° C. for 1 hour to perform an in-situ polymerization reaction, and the drawing ratio during the immersion process is 1.5 times.

[0045] The fiber was washed with distilled water, dried, stretched and shaped at a temperature of 60° C. for 1 h, and finally the conductive spandex fiber was obtained.

[0046] Example 3 S1. Preparation of initial spandex fiber: S1.1, under nitrogen protection, 75 kg of polytetramethylene ether glycol and 30 kg of diphenylmethane diisocyanate were stirred and reacted at 95°C for 1 hour to obtain prepolymer PPS; S1.2, PPS was transferred to a dissolver, 120 kg of DMAC was added, the temperature was cooled to 5°C, and it was poured into a reactor, and a mixed amine solution containing 5 kg of butanediamine and 1.2 kg of dipropylamine was added dropwise thereto to carry out chain extension reaction and chain termination reaction to obtain a chain extension solution.

[0047] S1.3, 0.1kg antioxidant (BHA), 1kg anti-ultraviolet agent (Tinuvin 328), 1kg anti-yellowing agent (Irganox1010), 0.1kg conductive agent (graphene oxide treated by high-pressure microfluidization, 50nm-1000nm) were added to DMAC for grinding, and then added to the chain extension solution, reacted and aged at 85℃ for 6h, and then filtered to obtain the spandex fiber polymerization stock solution. DMAC was removed through the channel, and the initial spandex fiber was obtained by dry spinning; the dry spinning conditions were as follows: the inlet air temperature was 38℃, the upper return air temperature was 48℃, the spinning temperature was 226℃, and the spinning speed was 235m / min.

[0048] S2. Post-processing operations: FeCl 3 Dissolve in water to prepare a concentration of 0.6 mol / L Fe 3+ The initial spandex fiber is immersed in Fe 3+ The aqueous solution was shaken for 1 hour to allow the initial spandex fibers to absorb Fe 3+ ; Conductive organic polymer monomer (pyrrole) and p-toluenesulfonic acid were dissolved in distilled water to obtain a mixed aqueous solution, wherein the concentration of the conductive organic polymer monomer was 0.6 mol / L and the concentration of p-toluenesulfonic acid was 0.6 mol / L. 3+ The initial spandex fiber in the aqueous solution is immersed in the mixed aqueous solution at 5° C. for 1 hour to perform an in-situ polymerization reaction, and the drawing ratio during the immersion process is 1.1 times.

[0049] The fiber was washed with distilled water, dried, stretched and shaped at a temperature of 40° C. for 3 h, and finally the conductive spandex fiber was obtained.

[0050] Example 4 S1. Preparation of initial spandex fiber: S1.1, under nitrogen protection, 60 kg of polytetramethylene ether glycol and 25 kg of diphenylmethane diisocyanate were stirred and reacted at 80°C for 1 hour to obtain prepolymer PPS; S1.2, PPS was transferred to a dissolver, 100 kg of DMAC was added, the temperature was cooled to 10°C, and it was poured into a reactor, and a mixed amine solution containing 3 kg of propylenediamine and 1.2 kg of dibutylamine was added dropwise thereto to carry out chain extension reaction and chain termination reaction to obtain a chain extension solution.

[0051] S1.3, 0.5kg antioxidant (BHT), 0.1kg anti-ultraviolet agent (Tinuvin 328), 0.1kg anti-yellowing agent (Irganox 1010), 0.5kg conductive agent (multilayer carbon nanotubes treated with high-pressure microfluidization, 50nm-1000nm) were added to DMAC for grinding, and then added to the chain extension solution, reacted and aged at 80℃ for 8h, and then filtered to obtain the spandex fiber polymerization stock solution. DMAC was removed through the channel, and the initial spandex fiber was obtained by dry spinning; the dry spinning conditions were as follows: the inlet air temperature was 40℃, the upper return air temperature was 50℃, the spinning temperature was 230℃, and the spinning speed was 240m / min.

[0052] S2. Post-processing operations: FeCl 3 Dissolve in water to prepare a concentration of 0.2 mol / L Fe 3+ The initial spandex fiber is immersed in Fe 3+ The aqueous solution was shaken for 1 hour to allow the initial spandex fibers to absorb Fe 3+ ; Conductive organic polymer monomer (pyrrole) and p-toluenesulfonic acid were dissolved in distilled water to obtain a mixed aqueous solution, wherein the concentration of the conductive organic polymer monomer was 0.2 mol / L and the concentration of p-toluenesulfonic acid was 0.2 mol / L. 3+ The initial spandex fiber in the aqueous solution is immersed in the mixed aqueous solution at 0° C. for 4 hours to perform an in-situ polymerization reaction, and the drawing ratio during the immersion process is 1.3 times.

[0053] The fiber was washed with distilled water, dried, stretched and shaped at a temperature of 50° C. for 2 h, and finally the conductive spandex fiber was obtained.

[0054] Comparative Example 1 The initial spandex fiber was prepared by the same method as in Example 1, but in this Comparative Example 1, no post-treatment operation was performed on the initial spandex fiber.

[0055] Comparative Example 2 The conductive spandex fiber was prepared by the same method as in Example 1, except that no conductive agent was added when the initial spandex fiber was prepared in this comparative example 2.

[0056] Comparative Example 3 The conductive spandex fiber was prepared by the same method as in Example 1, except that in Comparative Example 3, when the in-situ polymerization reaction was carried out, no drawing operation was performed during the immersion process.

[0057] Comparative Example 4 The conductive spandex fiber was prepared by the same method as in Example 1, except that in this comparative example 4, the conductive agent used was not subjected to high-pressure microfluidization treatment.

[0058] Comparative Example 5 The conductive spandex fiber was prepared by the same method as in Example 1, except that in Comparative Example 6, the spinning temperature of Comparative Example 5 was 245° C. (higher than the temperature condition specified in the present invention).

[0059] The conductive spandex fibers prepared in the above examples and comparative examples were subjected to performance tests. The specific test results are shown in Table 1 below. The test methods involved are as follows.

[0060] Conductive spandex fiber conductivity test: At 25°C, use a metal plate to press both ends of the conductive spandex fiber to fix it, leave it for 24 hours, then use a resistivity meter to test the resistance of the yarn bundle, and then divide the resistance by the distance between the probes to get the conductivity of the conductive spandex fiber.

[0061] Tensile strength and tensile test of conductive spandex fiber: Place the conductive spandex fiber in a tensile testing machine, pull it up at a speed of 20cm / min, and record the strength and tensile length of the conductive spandex fiber at the moment of breaking. Elongation at break = maximum tensile length / length to be tested. During the tensile test, observe whether the fiber will have powder loss problem.

[0062] Table 1 Conductive spandex fiber performance test data

[0063] From the data in Table 1 above, it can be seen that the conductive spandex fibers prepared by the preparation method of the present invention in Examples 1 to 4 have both good conductivity and strength properties, and will not fall off. By adding a conductive agent to the stock solution and then polymerizing a layer of conductive polymer in situ on the outside, there is a coordination effect between the conductive agent and the outer conductive polymer, which greatly enhances the antistatic effect. This allows the elastic fiber spandex fiber to have high conductivity while maintaining high elongation and high resilience. The fabric made using the conductive spandex fiber of the present invention has good antistatic properties, has great application potential in wearable smart fabrics such as health and sports monitoring, and has broad market prospects. Figure 1 The microscopic morphology of the conductive spandex fiber obtained in Example 1 is shown in FIG. Figure 1 It can be seen that the surface of the conductive spandex fiber prepared by the preparation method of the present invention is very uniform and has good application performance.

[0064] From the comparison of the data of Comparative Example 1 and Example 1, it can be seen that if no post-treatment operation is performed when preparing the conductive spandex fiber, the conductivity of the fiber is significantly reduced, and the strength performance also shows a downward trend.

[0065] From the data comparison of comparative example 2 and embodiment 1, it can be seen that if no conductive agent is added when preparing the conductive spandex fiber, the conductive properties and strength properties of the fiber will both decrease, and a small amount of powder will fall off during the stretching process. In the preparation method of the present invention, a conductive agent with a suitable particle size treated with high-voltage micro-jet is added during the preparation of the spandex fiber polymerization stock solution, so that the conductive agent is evenly distributed on the surface of the initial spandex fiber, thereby maintaining good strength of the spandex fiber, and also facilitating the in-situ polymerization of the conductive organic polymer monomer on the surface of the initial spandex fiber, and then coordinated with the appropriate drafting process during the in-situ polymerization process, so that the conductive polymer is evenly and stably attached to the conductive spandex fiber, the conductive spandex fiber has excellent mechanical strength and conductive properties, and the conductive polymer will not fall off after being stretched, rubbed or eroded by solvents, which significantly enhances the durability of the conductive spandex fiber.

[0066] From the comparison of the data of Comparative Example 3 and Example 1, it can be seen that if no stretching operation is performed during the immersion process when the in-situ polymerization reaction is carried out, the conductive performance will decrease, and it will be accompanied by a decrease in tensile strength and elongation at break.

[0067] From the comparison of the data of Comparative Example 4 and Example 1, it can be seen that if the conductive agent is not subjected to high-pressure microfluidization treatment, the conductive agent will be poorly dispersed and agglomerated, resulting in a significant decrease in conductive properties, accompanied by a decrease in tensile strength and elongation at break.

[0068] From the comparison of the data of Comparative Example 5 and Example 1, it can be seen that if the spinning temperature is increased to 245° C., the properties of the yarn will be affected, and further the tensile strength and elongation at break will be affected.

[0069] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] For those skilled in the art, several modifications and improvements may be made without departing from the concept of the present invention, all of which belong to the protection scope of the present invention. The protection scope of the present invention shall be based on the attached claims.

Claims

1. A method for preparing a uniform conductive spandex fiber, characterized in that: The preparation method is: S1. Preparation of initial spandex fiber: A conductive agent is added during the preparation of the spandex fiber polymerization solution, and then the initial spandex fiber is obtained by dry spinning, wherein the particle size of the conductive agent is 50nm-1000nm; S2. Post-processing operations: The initial spandex fiber was soaked in Fe 3+ aqueous solution, and then immersed in a mixed aqueous solution containing a conductive organic polymer monomer and p-toluenesulfonic acid to carry out an in-situ polymerization reaction, wherein the initial spandex fiber is subjected to a drafting operation during the immersion in the mixed aqueous solution; After the soaking is completed, the conductive spandex fiber is washed, dried, stretched and shaped to obtain the conductive spandex fiber.

2. The method for preparing a uniform conductive spandex fiber according to claim 1, characterized in that: The specific operations of step S1 are: S1.

1. Under the protection of inert gas, polytetramethylene ether glycol and 4,4-diphenylmethane diisocyanate are stirred and mixed to prepare a prepolymer; S1.2, adding DMAC to the prepolymer for dilution, and then adding a chain extender and a chain terminator to obtain a chain extension solution; S1.3, adding an antioxidant, an anti-ultraviolet agent, an anti-yellowing agent and a conductive agent to the chain extension solution and stirring to obtain a modified spandex fiber polymerization stock solution; S1.4, filtering the modified spandex fiber polymerization stock solution, removing DMAC through a channel, spinning, and obtaining initial spandex fibers.

3. The method for preparing a uniform conductive spandex fiber according to claim 2, characterized in that: The chain extender is a diamine; the terminator is a monoamine; The antioxidant is at least one of BHT and BHA; The anti-ultraviolet agent is at least one of Tinuvin 328 and Tinuvin 234; The anti-yellowing agent is at least one of Tinuvin 622 and Irganox 1010; The conductive agent is at least one of single-layer carbon nanotubes, multi-layer carbon nanotubes, carbon black, and graphene oxide, and the conductive agent is used after being treated with high-pressure microfluidization.

4. The method for preparing a uniform conductive spandex fiber according to claim 2, characterized in that: Calculated by weight, the ingredients include 50-75 parts of polytetramethylene ether glycol, 20-30 parts of 4,4-diphenylmethane diisocyanate, 2-5 parts of chain extender, 1-1.5 parts of chain terminator, 0.1-1 parts of antioxidant, 0.1-1 parts of anti-ultraviolet agent, 0.1-1 parts of anti-yellowing agent and 0.1-1 parts of conductive agent.

5. The method for preparing a uniform conductive spandex fiber according to claim 2, characterized in that: When preparing the prepolymer in step S1.1, the temperature is controlled at 60-95°C and the stirring time is 1-2h; In step S1.2, when preparing the chain extension solution, the temperature is controlled at 5-15°C and the viscosity is controlled at 3000-6000 poise; In step S1.3, when preparing the spandex fiber polymerization stock solution, the temperature is controlled at 60-85° C. and the viscosity is controlled at 1500-3000 poise.

6. The method for preparing a uniform conductive spandex fiber according to claim 1, characterized in that: The dry spinning conditions are: inlet air temperature is 38-42°C, upper return air temperature is 48-52°C, spinning temperature is 226-234°C, and spinning speed is 235-245m / min.

7. The method for preparing a uniform conductive spandex fiber according to claim 1, characterized in that: The Fe 3+ Fe in aqueous solution 3+ The concentration is 0.05-0.6 mol / L, Fe 3+ Fe in aqueous solution 3+ The ratio of the concentration of the conductive organic polymer monomer in the mixed aqueous solution to the concentration of the conductive organic polymer monomer in the mixed aqueous solution is (1-3):1; the ratio of the concentration of the conductive organic polymer monomer in the mixed aqueous solution to the concentration of p-toluenesulfonic acid is 1:(1-1.5).

8. The method for preparing a uniform conductive spandex fiber according to claim 1, characterized in that: The drafting ratio of the initial spandex fiber during the drafting operation during the soaking in the mixed aqueous solution is 1.1-1.5; The temperature of the in-situ polymerization reaction is 0-5°C, and the reaction time is 60-240min.

9. The method for preparing a uniform conductive spandex fiber according to claim 1, characterized in that: The conductive organic polymer monomer is at least one of aniline and pyrrole; The drying temperature is 40-60° C., and the drying time is 1-3 hours.

10. A uniform conductive spandex fiber, characterized in that: The conductive spandex fiber is prepared according to the preparation method according to any one of claims 1 to 9.

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