A low yarn breakage rate spandex fiber and a method for preparing the same

Abstract

The application discloses a low yarn breakage rate spandex fiber and a preparation method thereof. The preparation method comprises the following steps: dispersing modified nano molybdenum disulfide into DMF, uniformly ultrasonic dispersing to obtain a modified nano molybdenum disulfide solution; adding the modified nano molybdenum disulfide solution into a polyurethane urea solution, stirring and mixing to obtain a spandex spinning stock solution, extruding the spandex spinning stock solution through a spinneret in a duct to perform dry spinning, and obtaining the low yarn breakage rate spandex fiber. The modified nano molybdenum disulfide is obtained by modifying nano molybdenum disulfide by KH570, octavinyl POSS and sodium tetradecylene sulfonate. The modified particles are integrated with multiple functions such as lubrication, reinforcement and antistatic property, are uniformly distributed in the fiber, and cooperatively improve the mechanical property, thermal stability and unwinding performance of the spandex, so that the yarn breakage rate in the production and use process is significantly reduced, and the product quality and reliability are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of spandex technology, specifically to a low-breakage-rate spandex fiber and its preparation method. Background Technology

[0002] Spandex fiber, as an important elastic fiber, possesses excellent elastic recovery, fatigue resistance, and chemical stability, and is widely used in clothing, medical textiles, sporting goods, and other fields. With the rapid development of the textile industry and the increasing consumer demand for high-quality elastic fabrics, the market demand for spandex fiber continues to expand, placing higher requirements on its overall performance.

[0003] However, high fiber breakage rate has always been a key technical challenge plaguing the industry during the production and use of spandex fibers. During spinning, fibers are prone to breakage due to stress concentration, interface defects, and other factors. In subsequent processing and use, spandex fibers also frequently break during high-speed unwinding due to problems such as high surface friction coefficient, static electricity accumulation, and fiber adhesion, which seriously affects production efficiency and product quality, and increases production costs.

[0004] To address these issues, existing technologies primarily improve spandex fiber performance by optimizing spinning process parameters, improving spinning equipment, and adjusting polymer molecular structure. However, these methods have limited effectiveness in reducing fiber breakage rate and cannot fundamentally solve the problem.

[0005] In recent years, nanomaterials have shown great potential in the field of fiber modification. The introduction of nanoparticles can significantly improve the mechanical properties, thermal stability, and surface characteristics of fibers. Among them, molybdenum disulfide (MoS2), as a typical layered transition metal sulfide, has attracted widespread attention in the field of composite materials due to its excellent lubrication properties and unique physicochemical properties. However, the direct application of nano-molybdenum disulfide to spandex fibers faces key technical obstacles such as poor dispersibility and poor compatibility with the polymer matrix, making it difficult to fully realize the expected modification effect and even potentially having a negative impact on fiber properties.

[0006] Therefore, there is an urgent need to develop an effective nano-molybdenum disulfide surface modification technology to achieve its uniform dispersion and good compatibility in the spandex matrix, thereby producing spandex fibers with low breakage rate and high performance to meet the development needs of the modern textile industry. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a low-breakage spandex fiber and its preparation method. This invention solves the problem of dispersion and compatibility of molybdenum disulfide nanoparticles in the spandex matrix through multifunctional composite modification. Simultaneously, the modified particles integrate multiple functions such as lubrication, reinforcement, and antistatic properties, ensuring uniform distribution within the fiber. This synergistically improves the mechanical properties, thermal stability, and unwinding performance of the spandex, ultimately significantly reducing the breakage rate during production and use, and effectively improving product quality and reliability.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A method for preparing spandex fiber with low breakage rate includes the following steps: dispersing modified molybdenum disulfide nanoparticles in DMF and ultrasonically dispersing them uniformly to obtain a modified molybdenum disulfide nanoparticle solution; adding the modified molybdenum disulfide nanoparticle solution to a polyurethane urea solution and stirring to obtain a spandex spinning solution; and dry spinning the solution through a spinneret in a channel to obtain the spandex fiber with low breakage rate.

[0010] Preferably, the modified nano-molybdenum dioxide is prepared by the following method steps:

[0011] (1) Disperse nano-molybdenum disulfide in deionized water, ultrasonically disperse, then add hydrogen peroxide aqueous solution dropwise, stir the reaction, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0012] Hydroxylation Modification of Nano-Molybdenum Disulfide: Nano-Molybdenum disulfide undergoes a surface oxidation reaction under the action of hydrogen peroxide. H₂O₂, acting as a strong oxidizing agent, attacks the edge and defect sites of the MoS₂ layered structure, oxidizing some sulfur atoms to sulfonic acid groups (-SO₃H). Simultaneously, molybdenum atoms are oxidized and combine with water molecules to form surface hydroxyl groups (-Mo-OH). During the reaction, H₂O₂ decomposes to generate reactive oxygen atoms, promoting the chemical activation of the MoS₂ surface and introducing a large number of hydroxyl active sites while maintaining the integrity of the layered structure.

[0013] Preferably, in step (1), the ratio of nano-molybdenum disulfide, deionized water, and hydrogen peroxide aqueous solution is 10g: 200-400mL: 20-50mL; and the concentration of hydrogen peroxide aqueous solution is 20-35wt%.

[0014] Preferably, in step (1), ultrasonic dispersion is performed for 20–40 min; and the stirring reaction is performed at 50–70 °C for 2–5 h.

[0015] (2) Activated molybdenum disulfide was dispersed in anhydrous ethanol, ultrasonically dispersed, and then KH570 and a small amount of deionized water were added to adjust the pH of the system. The reaction was heated, and the product was centrifuged, washed, and dried to obtain pretreated molybdenum disulfide.

[0016] Silane coupling agent modification: KH570 silane coupling agent first undergoes a hydrolysis reaction in the presence of water, where the methoxy group (-OCH3) hydrolyzes to generate silanol groups (-Si-OH) and release methanol. Subsequently, the silanol groups generated by hydrolysis undergo a condensation reaction with the hydroxyl groups on the activated molybdenum disulfide surface to form Si-O-Mo covalent bonds, while simultaneously removing water molecules. Through this silane coupling reaction, the methacrylate double bonds in KH570 are successfully grafted onto the molybdenum disulfide surface, providing polymerizable active sites for subsequent polymerization reactions.

[0017] Preferably, in step (2), the ratio of activated molybdenum disulfide, anhydrous ethanol, KH570, and deionized water is 10g: 200-400mL: 1-3g: 2-5mL.

[0018] Preferably, in step (2), the system is ultrasonically dispersed for 20-40 min; the pH of the system is adjusted to 4-5 with acetic acid solution; and the reaction is carried out at 65-80℃ for 4-7 h.

[0019] (3) The pretreated molybdenum disulfide was dispersed in DMF and ultrasonically dispersed to obtain a suspension. Then, octavinyl POSS was dissolved in toluene. Subsequently, the octavinyl POSS toluene solution was added to the suspension, and sodium tetradecene sulfonate was added. Azobisisobutyronitrile was added under a nitrogen atmosphere, and the reaction was heated. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

[0020] Free radical copolymerization reaction: Under the action of free radicals generated by the thermal decomposition of AIBN initiator, the methacrylate double bonds, the vinyl groups of octavinyl POSS, and the olefin double bonds of sodium tetradecene sulfonate on the surface of pretreated molybdenum disulfide simultaneously undergo ring opening and participate in free radical polymerization, ultimately forming an organic-inorganic composite modified molybdenum disulfide.

[0021] Preferably, in step (3), the ratio of the amount of pretreated molybdenum disulfide, DMF, octavinyl POSS, toluene, sodium tetradecene sulfonate, and azobisisobutyronitrile is 10g: 200-300mL: 1-4g: 100mL: 3-6g: 0.05-0.2g.

[0022] Preferably, in step (3), ultrasonic dispersion is performed for 40–60 min; the temperature reaction conditions are 70–85 °C for 6–12 h.

[0023] Preferably, the concentration of the modified nano-molybdenum disulfide solution is 5-20 wt%; the ratio of modified nano-molybdenum disulfide to polyurethane urea solution is 2-8 g: 100 mL; ultrasonic dispersion is performed for 1-3 h; and the stirring and mixing conditions are 40-60 °C for 24-36 h.

[0024] The present invention also claims protection for a low-breakage spandex fiber prepared using the aforementioned preparation method.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. This invention provides a method for preparing spandex fibers with low breakage rate. Through multi-step controllable surface chemical modification of nano-molybdenum disulfide, a functionalized nano-additive with excellent dispersibility and stability in spandex spinning solvent (DMF) is successfully prepared. The method has clear steps and mild, controllable reaction conditions, enabling the final additive to be stably and uniformly dispersed in a polyurethane urea solution, forming a homogenized spinning solution. This provides a key prerequisite for preparing high-performance spandex fibers, and the overall process is simple and easy to industrialize.

[0027] 2. This invention provides a method for preparing modified nano-molybdenum disulfide. First, the core nano-molybdenum disulfide itself is an excellent nano-lubricating particle, and its introduction can effectively improve the unwinding performance of spandex fibers. Through multi-step modification, octavinyl POSS not only acts as a nanofiller with its cage-like structure, physically enhancing the mechanical properties of spandex fibers, such as hardness, abrasion resistance, and thermal stability, but also effectively reduces surface roughness and static friction coefficient by enriching on the fiber surface. This significantly reduces fiber adhesion during unwinding and alleviates the problem of stickiness at the bottom of the yarn cake after prolonged storage, extending the service life. Simultaneously, the tetradecene sulfonate introduced through copolymerization acts as a highly efficient antistatic agent, ensuring the antistatic properties of the spandex yarn. Ultimately, the nano-lubricating effect of molybdenum disulfide, the physical reinforcement and surface modification effect of POSS, and the antistatic effect of tetradecene sulfonate work synergistically to ensure stable tension and smooth unwinding during the unwinding process, thereby endowing spandex fibers with excellent comprehensive performance and a significantly reduced breakage rate. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. Of course, the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0029] Unless otherwise specified, all chemical reagents and materials in this invention are purchased from the market or synthesized from raw materials purchased from the market.

[0030] The particle size of nano-molybdenum disulfide is 50–100 nm;

[0031] The CAS number for octavinyl POSS is 69655-76-1;

[0032] The polyurethane urea solution is prepared by the following steps: Dimethylformamide and polytetramethylene ether glycol are added sequentially to a prepolymer tank, followed by 4,4-diphenylmethane diisocyanate. The molar ratio of isocyanate groups in the diisocyanate to hydroxyl groups in the polyether glycol is 1.70–1.90. The prepolymerization reaction is carried out at 50–60°C under a nitrogen atmosphere for 1.5–2 hours to obtain a prepolymer solution. Dimethylformamide is then added to the prepolymer tank to dilute the prepolymer solution. The solution is then transferred to a chain extender tank, cooled to 10–15°C, and ethylenediamine and piperidine (ethylenediamine and piperidine are 4–6% and 1–2% of the prepolymer solution mass, respectively) are slowly added to carry out a chain extension reaction, yielding a 30–38 wt% polyurethane urea solution.

[0033] A method for preparing spandex fiber with low breakage rate includes the following steps:

[0034] (1) Disperse 10g of nano molybdenum disulfide in 200-400mL of deionized water, ultrasonically disperse for 20-40min, then add 20-50mL of 20-35wt% hydrogen peroxide aqueous solution, stir and react at 50-70℃ for 2-5h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0035] (2) Disperse 10g of activated molybdenum disulfide in 200-400mL of anhydrous ethanol, sonicate for 20-40min, then add 1-3g of KH570 and 2-5mL of deionized water, adjust the pH of the system to 4-5 with acetic acid aqueous solution, heat to 65-80℃ and react for 4-7h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0036] (3) Disperse 10g of pretreated molybdenum disulfide in 200-300mL of DMF and sonicate for 40-60min to obtain a suspension. Then dissolve 1-4g of octavinyl POSS in 100mL of toluene. Add the octavinyl POSS toluene solution to the suspension, then add 3-6g of sodium tetradecene sulfonate. Add 0.05-0.2g of azobisisobutyronitrile under a nitrogen atmosphere. Heat to 70-85℃ and react for 6-12h. Cool, centrifuge, wash and dry the product to obtain modified nano molybdenum disulfide.

[0037] (4) The modified nano molybdenum disulfide is dispersed in DMF and ultrasonically dispersed for 1-3 hours to obtain a 5-20 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution is added to a polyurethane urea solution (the ratio of modified nano molybdenum disulfide to polyurethane urea solution is 2-8 g: 100 mL), and stirred and mixed at 40-60°C for 24-36 hours to obtain a spandex spinning solution. The solution is then dry-spun in a channel by extrusion through a spinneret to obtain the low-breakage spandex fiber.

[0038] The present invention will be further described below through specific embodiments.

[0039] Example 1

[0040] A method for preparing spandex fiber with low breakage rate includes the following steps:

[0041] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 50mL of 30wt% hydrogen peroxide aqueous solution, stir at 70℃ for 2h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0042] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 3g of KH570 and 5mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 80℃ and react for 4h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0043] (3) 10g of pretreated molybdenum disulfide was dispersed in 250mL of DMF and ultrasonically dispersed for 50min to obtain a suspension. Then, 4g of octavinyl POSS was dissolved in 100mL of toluene. Subsequently, the octavinyl POSS toluene solution was added to the suspension, followed by 6g of sodium tetradecene sulfonate. 0.2g of azobisisobutyronitrile was added under a nitrogen atmosphere. The mixture was heated to 85℃ and reacted for 6h. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

[0044] (4) The modified nano molybdenum disulfide was dispersed in DMF and ultrasonically dispersed for 3 h to obtain a 15 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution was added to a 34.7 wt% polyurethane urea solution (the ratio of modified nano molybdenum disulfide to polyurethane urea solution was 8 g: 100 mL), and stirred and mixed at 50 °C for 30 h to obtain a spandex spinning solution. The solution was then dry spun in a channel by extrusion through a spinneret to obtain the low-breakage spandex fiber.

[0045] Example 2

[0046] A method for preparing spandex fiber with low breakage rate includes the following steps:

[0047] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 40mL of 30wt% hydrogen peroxide aqueous solution, stir at 60℃ for 3h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0048] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 2g of KH570 and 4mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 75℃ and react for 5h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0049] (3) 10g of pretreated molybdenum disulfide was dispersed in 250mL of DMF and ultrasonically dispersed for 50min to obtain a suspension. Then, 3g of octavinyl POSS was dissolved in 100mL of toluene. Subsequently, the octavinyl POSS toluene solution was added to the suspension, and then 5g of sodium tetradecene sulfonate was added. Under a nitrogen atmosphere, 0.15g of azobisisobutyronitrile was added, and the temperature was raised to 80℃ for 8h. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

[0050] (4) The modified nano molybdenum disulfide was dispersed in DMF and ultrasonically dispersed for 2 h to obtain a 15 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution was added to a 34.7 wt% polyurethane urea solution (the ratio of modified nano molybdenum disulfide to polyurethane urea solution was 6 g: 100 mL), and stirred and mixed at 50 °C for 30 h to obtain a spandex spinning solution. The solution was then dry spun in a channel by extrusion through a spinneret to obtain the low-breakage spandex fiber.

[0051] Example 3

[0052] A method for preparing spandex fiber with low breakage rate includes the following steps:

[0053] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 30mL of 30wt% hydrogen peroxide aqueous solution, stir at 60℃ for 4h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0054] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 2g of KH570 and 3mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 70℃ and react for 6h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0055] (3) 10g of pretreated molybdenum disulfide was dispersed in 250mL of DMF and ultrasonically dispersed for 50min to obtain a suspension. Then, 2g of octavinyl POSS was dissolved in 100mL of toluene. Subsequently, the octavinyl POSS toluene solution was added to the suspension, and then 4g of sodium tetradecene sulfonate was added. Under a nitrogen atmosphere, 0.1g of azobisisobutyronitrile was added, and the temperature was raised to 75℃ for 8h. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

[0056] (4) The modified nano molybdenum disulfide was dispersed in DMF and ultrasonically dispersed for 2 h to obtain a 15 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution was added to a 34.7 wt% polyurethane urea solution (the ratio of modified nano molybdenum disulfide to polyurethane urea solution was 4 g: 100 mL), and stirred and mixed at 50 °C for 30 h to obtain a spandex spinning solution. The solution was then dry spun in a channel by extrusion through a spinneret to obtain the low-breakage spandex fiber.

[0057] Example 4

[0058] A method for preparing spandex fiber with low breakage rate includes the following steps:

[0059] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 20mL of 30wt% hydrogen peroxide aqueous solution, stir at 50℃ for 5h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0060] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 1g of KH570 and 2mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 65℃ and react for 7h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0061] (3) 10g of pretreated molybdenum disulfide was dispersed in 250mL of DMF and ultrasonically dispersed for 50min to obtain a suspension. Then, 1g of octavinylPOSS was dissolved in 100mL of toluene. Subsequently, the octavinylPOSS toluene solution was added to the suspension, followed by 3g of sodium tetradecene sulfonate. 0.05g of azobisisobutyronitrile was added under a nitrogen atmosphere. The mixture was heated to 70℃ and reacted for 12h. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

[0062] (4) The modified nano molybdenum disulfide was dispersed in DMF and ultrasonically dispersed for 1 h to obtain a 15 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution was added to a 34.7 wt% polyurethane urea solution (the ratio of modified nano molybdenum disulfide to polyurethane urea solution was 2 g: 100 mL), and stirred and mixed at 50 °C for 30 h to obtain a spandex spinning solution. The solution was then dry spun in a channel by extrusion through a spinneret to obtain the low-breakage spandex fiber.

[0063] Comparative Example 1

[0064] A method for preparing spandex fiber includes the following steps:

[0065] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 50mL of 30wt% hydrogen peroxide aqueous solution, stir at 70℃ for 2h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0066] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 3g of KH570 and 5mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 80℃ and react for 4h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0067] (3) 10g of pretreated molybdenum disulfide was dispersed in 250mL of DMF and ultrasonically dispersed for 50min to obtain a suspension. Then, 4g of octavinylPOSS was dissolved in 100mL of toluene. Subsequently, the octavinylPOSS toluene solution was added to the suspension. 0.2g of azobisisobutyronitrile was added under a nitrogen atmosphere. The temperature was raised to 85℃ and reacted for 6h. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

[0068] (4) The modified nano molybdenum disulfide and sodium tetradecene sulfonate were dispersed in DMF and ultrasonically dispersed for 3 h to obtain a 15 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution was added to a 34.7 wt% polyurethane urea solution (the ratio of modified nano molybdenum disulfide, sodium tetradecene sulfonate and polyurethane urea solution was 8 g: 4 g: 100 mL), and stirred and mixed at 50 °C for 30 h to obtain spandex spinning solution. The solution was then dry spun in the channel by extrusion through a spinneret to obtain spandex fiber.

[0069] Comparative Example 2

[0070] A method for preparing spandex fiber includes the following steps:

[0071] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 50mL of 30wt% hydrogen peroxide aqueous solution, stir at 70℃ for 2h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0072] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 3g of KH570 and 5mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 80℃ and react for 4h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0073] (3) Disperse 10g of pretreated molybdenum disulfide into 250mL of DMF, ultrasonically disperse for 50min to obtain a suspension, then add 6g of sodium tetradecene sulfonate, add 0.2g of azobisisobutyronitrile under a nitrogen atmosphere, heat to 85℃ and react for 6h, cool, centrifuge, wash and dry the product to obtain modified nano molybdenum disulfide.

[0074] (4) The modified nano molybdenum disulfide and octavinyl POSS were dispersed in DMF and ultrasonically dispersed for 3 h to obtain a 15 wt% modified nano molybdenum disulfide solution; the modified nano molybdenum disulfide solution was added to a 34.7 wt% polyurethane urea solution (the ratio of modified nano molybdenum disulfide, octavinyl POSS and polyurethane urea solution was 8 g: 4 g: 100 mL), and stirred and mixed at 50 °C for 30 h to obtain a spandex spinning solution. The solution was then dry spun in a channel by extrusion through a spinneret to obtain the spandex fiber.

[0075] Comparative Example 3

[0076] A method for preparing spandex fiber includes the following steps:

[0077] (1) Disperse 10g of nano molybdenum disulfide into 300mL of deionized water, sonicate for 30min, then add 50mL of 30wt% hydrogen peroxide aqueous solution, stir at 70℃ for 2h, filter, wash and dry the product to obtain activated molybdenum disulfide;

[0078] (2) Disperse 10g of activated molybdenum disulfide in 300mL of anhydrous ethanol, sonicate for 30min, then add 3g of KH570 and 5mL of deionized water, adjust the pH of the system to 4.5 with acetic acid aqueous solution, heat to 80℃ and react for 4h, centrifuge, wash and dry the product to obtain pretreated molybdenum disulfide;

[0079] (3) Disperse the pretreated molybdenum disulfide in DMF and ultrasonically disperse for 3 h to obtain a 15 wt% pretreated molybdenum disulfide solution; add the pretreated molybdenum disulfide solution to a 34.7 wt% polyurethane urea solution (the ratio of pretreated molybdenum disulfide to polyurethane urea solution is 8 g: 100 mL), stir and mix at 50 °C for 30 h to obtain spandex spinning solution, and dry spin the spandex fiber by extruding it through a spinneret in the channel.

[0080] The spandex fibers prepared in Examples 1-4 and Comparative Examples 1-3 were subjected to performance tests. The breaking elongation was tested using a yarn tensile strength tester according to FZ / T 50006-2013 "Test Method for Tensile Properties of Spandex Yarn"; the elastic recovery rate was determined using a single yarn tensile strength tester and a one-time constant elongation test according to FZ / T 50007-2012 "Test Method for Elasticity of Spandex Yarn"; the surface resistance of the spandex fibers was tested according to GB / T12703.4-2010 "Evaluation of Electrostatic Properties of Textiles - Part 4: Resistivity"; the unwinding property of the fibers was evaluated using a spandex unwinding tester under deterioration conditions of 65℃ for 72 hours, and the surface friction coefficient of the fiber samples was also tested. Specific data are shown in Table 1.

[0081] Table 1 Results of fiber sample performance tests

[0082]

[0083] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing spandex fibers with low breakage rate, characterized in that, The process includes the following steps: dispersing modified nano-molybdenum disulfide in DMF and ultrasonically dispersing it evenly to obtain a modified nano-molybdenum disulfide solution; adding the modified nano-molybdenum disulfide solution to a polyurethane urea solution and stirring to obtain a spandex spinning solution; and dry spinning the solution through a spinneret in a channel to obtain the low-breakage spandex fiber. The modified nano-molybdenum disulfide was prepared by the following steps: (1) Disperse nano-molybdenum disulfide in deionized water, ultrasonically disperse, then add hydrogen peroxide aqueous solution dropwise, stir the reaction, filter, wash and dry the product to obtain activated molybdenum disulfide; (2) Activated molybdenum disulfide was dispersed in anhydrous ethanol, ultrasonically dispersed, and then KH570 and a small amount of deionized water were added to adjust the pH of the system. The reaction was heated, and the product was centrifuged, washed, and dried to obtain pretreated molybdenum disulfide. (3) The pretreated molybdenum disulfide was dispersed in DMF and ultrasonically dispersed to obtain a suspension. Then, octavinyl POSS was dissolved in toluene. Subsequently, the octavinyl POSS toluene solution was added to the suspension, and sodium tetradecene sulfonate was added. Azobisisobutyronitrile was added under a nitrogen atmosphere, and the reaction was heated. The product was cooled, centrifuged, washed, and dried to obtain modified nano molybdenum disulfide.

2. The preparation method according to claim 1, characterized in that, In step (1), the ratio of nano molybdenum disulfide, deionized water, and hydrogen peroxide aqueous solution is 10g: 200~400mL: 20~50mL; the concentration of hydrogen peroxide aqueous solution is 20~35wt%.

3. The preparation method according to claim 1, characterized in that, In step (1), ultrasonic dispersion is performed for 20-40 minutes; the stirring reaction conditions are 50-70℃ for 2-5 hours.

4. The preparation method according to claim 1, characterized in that, In step (2), the ratio of activated molybdenum disulfide, anhydrous ethanol, KH570, and deionized water is 10g: 200~400mL: 1~3g: 2~5mL.

5. The preparation method according to claim 1, characterized in that, In step (2), the system is ultrasonically dispersed for 20-40 minutes; the pH of the system is adjusted to 4-5 with acetic acid solution; and the reaction is carried out at 65-80℃ for 4-7 hours.

6. The preparation method according to claim 1, characterized in that, In step (3), the ratio of the amount of pretreated molybdenum disulfide, DMF, octavinyl POSS, toluene, sodium tetradecyl sulfonate, and azobisisobutyronitrile is 10g: 200~300mL: 1~4g: 100mL: 3~6g: 0.05~0.2g.

7. The preparation method according to claim 1, characterized in that, In step (3), ultrasonic dispersion is performed for 40-60 minutes; the reaction is carried out at 70-85℃ for 6-12 hours.

8. The preparation method according to claim 1, characterized in that, The concentration of the modified nano-molybdenum disulfide solution is 5~20wt%; the ratio of modified nano-molybdenum disulfide to polyurethane urea solution is 2~8g:100mL; ultrasonic dispersion is performed for 1~3h; and stirring and mixing are carried out at 40~60℃ for 24~36h.

9. A low-breakage spandex fiber prepared by the preparation method according to any one of claims 1 to 8.

Images