Flame-retardant high-elasticity fabric and preparation method thereof
By blending modified soybean oil diethanolamide with polyurethane fibers and combining it with modified aramid fibers, a flame-retardant and highly elastic fabric was prepared. This solved the problems of easy aging and flammability of traditional high-elastic fabrics, and improved the high strength, flame retardancy and UV resistance properties, meeting the comprehensive performance requirements of high-end protective clothing.
Patent Information
- Application Number
- CN202511342778.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-19
- Publication Date
- 2025-12-16
AI Technical Summary
Traditional high-elasticity fabrics are prone to aging and flammability, and existing technologies cannot effectively solve the problem of balancing flame retardancy, durability, and comfort.
Modified soybean oil was prepared by reacting soybean oil with 2-mercaptobenzimidazole and then with 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride. Subsequently, it was reacted with diethanolamine to synthesize modified soybean oil diethanolamide, which was used as a functional chain extender. This solution was polymerized with polytetramethylene ether glycol 2000, isophorone diisocyanate, and diol UV absorber to prepare a modified polyurethane solution. Functionalized polyurethane fibers were prepared by wet spinning. The functionalized polyurethane fibers were then blended with flame-retardant aramid fibers in a certain proportion and post-treated to obtain a flame-retardant high-elasticity fabric.
It achieves comprehensive performance in terms of high elasticity, high strength, permanent flame retardancy, UV resistance, and oxidation resistance, meeting the stringent requirements of high-end protective clothing.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of textile materials, in particular to a flame-retardant high-elasticity fabric and a preparation method thereof. BACKGROUND
[0002] High-elasticity fabrics are widely used in outdoor sports clothing, professional protective equipment and high-end casual wear due to their excellent comfort, stretch recovery and fit. However, traditional high-elasticity fabrics mostly use spandex as the core component, but spandex is prone to aging, has poor elastic durability, and is highly flammable, and melts and drips when burning, carrying the flame to spread and causing serious fire safety hazards. At the same time, with the increasing demand for safety protection and environmental protection, single-function elastic fabrics have been difficult to meet the market demand for multifunctional textiles with comfort, safety and durability.
[0003] In recent years, although some progress has been made in modifying elastic fibers by adding flame retardants, there are still problems such as loss of elasticity, poor durability, hard hand feeling or environmental pollution due to high addition amount. Aramid fibers have intrinsic flame retardance and high-temperature resistance, but they are too rigid and lack elasticity, so they cannot meet the requirements of high-elasticity applications when used alone. Therefore, it is a key technical problem in the current textile industry to develop a fabric that can synergistically utilize the advantages of elastic fibers and high-performance flame-retardant fibers, and to prepare a fabric with excellent flame retardance, high resilience and comfort through molecular structure design and spinning process innovation, which is of great significance to improve the safety and comfort of protective clothing. SUMMARY
[0004] The present application relates to the technical field of textile materials, in particular to a flame-retardant high-elasticity fabric and a preparation method thereof.
[0005] To solve the above technical problems, the present application provides the following technical solutions:
[0006] A flame-retardant high-elasticity fabric is prepared by mixing functional polyurethane fibers and modified aramid fibers in a certain proportion and then post-treating.
[0007] As an optimization, the functional polyurethane fibers are prepared by gradually polymerizing polytetramethylene ether glycol 2000, isophorone diisocyanate, diol UV absorber and modified soybean oil diethanolamide, and then wet spinning.
[0008] As an optimization, the modified soybean oil diethanolamide is prepared by reacting modified soybean oil with 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl chloride after photo-induced grafting of soybean oil with 2-mercaptobenzimidazole, and then acylating with diethanolamine.
[0009] As an optimization, the modified aramid fiber is made from m-phenylenediamine and phenyl phosphine dichloride to synthesize a flame-retardant intermediate, and then participates in m-aramid polymerization.
[0010] A preparation method of a flame-retardant high-elasticity fabric comprises the following preparation steps:
[0011] (1) Soybean oil, 2-mercaptobenzimidazole, a photoinitiator, and ethanol are mixed in a mass ratio of 1:(6-10):(0.05-0.07):(10-30), and stirred at 25-30°C and 300-500 r / min until completely dissolved, and then subjected to 365 nm ultraviolet irradiation for 1-3 h, and then the ethanol is removed by rotary evaporation, and 4-8 times of anhydrous N,N-dimethylformamide is added based on the mass of the soybean oil, and then stirred at 50-70°C and 200-400 r / min for 0.5-1.5 h, and then cooled to 25-30°C, and then 1.2-1.5 equivalents of sodium hydride relative to the benzimidazole unit is added in a nitrogen atmosphere, and then continuously stirred for 1-2 h, and then heated to 30-50°C, and then 1.2-1.5 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit is added, and then continuously stirred for 12-48 h, and then 4-5 drops of methanol is added dropwise for quenching, and then rotary evaporation and washing are performed to obtain a modified soybean oil; diethanolamine and sodium methoxide are mixed in a mass ratio of 1:0.01-0.03, and then stirred at 70-90°C and 200-400 r / min for 10-30 min; and then 0.8-1.2 parts of the modified soybean oil is added based on the mass of the diethanolamine, and then continuously stirred at 100-140°C for 2-6 h, and then dehydrated and vacuum dried to obtain a modified soybean oil diethanolamide;
[0012] (2) Polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanolamide, and dibutyltin dilaurate are weighed in a molar ratio of 1:0.3:4:2.7:(0.0008-0.0012); in a nitrogen atmosphere, the polytetramethylene ether glycol 2000, diol ultraviolet absorber, and isophorone diisocyanate are mixed, and then stirred at 70-90°C and 300-500 r / min for 1-3 h, and then cooled to 40-80°C, and then the dibutyltin dilaurate and the modified soybean oil diethanolamide are added, and then continuously stirred for 5-9 h to obtain a modified polyurethane solution; the prepared modified polyurethane solution is degassed and filtered, extruded into a 40-50 wt% dimethyl carbonate aqueous solution through a spinneret for wet spinning, and then subjected to drawing, drying, and winding to obtain a functionalized polyurethane fiber;
[0013] (3) Under the protection of nitrogen, m-phenylenediamine, triethylamine and anhydrous acetonitrile are mixed in a mass ratio of 1: (0.7-1.1): (4-6) and stirred at 25-30°C and 200-400 r / min for 10-30 min to obtain a m-phenylenediamine solution; phenylphosphonic dichloride is weighed in an amount of 0.3-0.4 times the molar amount of m-phenylenediamine and dissolved in anhydrous acetonitrile at 20-30 wt% to obtain a phenylphosphonic dichloride solution; the phenylphosphonic dichloride solution is added dropwise into the m-phenylenediamine solution under stirring at 0-5°C and 200-400 r / min for 1-3 h, and the reaction is continued at 25-30°C for 10-14 h, followed by filtration, rotary evaporation, and ice water washing to obtain a flame-retardant intermediate; the m-phenylenediamine and the flame-retardant intermediate are mixed in a molar ratio of 1:0.01-0.05 under a nitrogen atmosphere, and the mixture is added into N,N-dimethylacetamide at 20-30 wt% and stirred at 25-30°C and 200-400 r / min until complete dissolution, followed by cooling to -15 to -10°C, dropwise addition of isophthaloyl chloride in an amount of 1.01-1.05 times the molar amount of m-phenylenediamine, and further stirring at 50-70°C for 1-3 h, during which the pH of the system is controlled to 7-8 with a saturated calcium hydroxide solution to obtain a modified aramid spinning solution; the modified aramid spinning solution is extruded through a spinneret into a 50-55 wt% N,N-dimethylacetamide aqueous solution coagulation bath for wet spinning, followed by drawing, drying, and winding to obtain flame-retardant aramid fibers;
[0014] (4) The functionalized polyurethane fiber and the flame-retardant aramid fiber are blended in a ratio of 1:3 into an elastic yarn with a double-strand structure of 12.5 tex x 2 and a twist of 70 T / m; the elastic yarn is knitted on a multifunctional flat knitting machine and post-treated to obtain a flame-retardant high-elasticity fabric.
[0015] As an optimization, the preparation method of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride in step (1) is as follows: 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid is dissolved in thionyl chloride at 20-30 wt% and stirred at 25-30°C and 300-500 r / min for 2-4 h under reflux, followed by evaporation under reduced pressure to obtain the product.
[0016] As an optimization, the modified soybean oil diethanolamide reaction process in step (1) is as follows:
[0017]
[0018] As an optimization, the diol ultraviolet absorber in step (2) is 2-[3'-(2H-benzotriazole)-5'-tert-butyl-4'-hydroxy-phenyl]-2-ethylpropane-1,3-propanediol, which is of analytical purity and is available from Changzhou Enke New Material Technology Co., Ltd.
[0019] As optimization, the main spinning process of step (2) is as follows: the spinneret size is 0.1 mm in diameter x 30 round holes, the spinning speed is 0.5 mL / min, the coagulation bath temperature is kept at 20-25 DEG C, and the obtained primary fiber is washed with water, stretched 2.5 times in a hot water bath at 50 DEG C, and dried at 80-100 DEG C.
[0020] As optimization, the main spinning process of step (3) is as follows: the spinneret size is 0.1 mm in diameter x 30 round holes, the spinning speed is 1.2 mL / min, the coagulation bath temperature is 55-60 DEG C, the obtained primary fiber is washed with water, stretched 2.73 times in a hot water bath at 90 DEG C, dried at 120-140 DEG C, and stretched 1.45 times on a hot plate at 300-340 DEG C.
[0021] As optimization, the weaving and finishing process of step (4) is as follows: the elastic yarn is woven into a plain fabric with a warp-weft density of 320x250 roots / 10 cm and a thickness of 0.6+ / -0.04 mm on a multifunctional flat knitting machine, and the flame-retardant high-elasticity fabric is prepared after singeing, continuous boiling, drying, and calendering.
[0022] Compared with the prior art, the present application has the following beneficial effects:
[0023] In the preparation of the flame-retardant high-elasticity fabric, the modified soybean oil is prepared by reacting soybean oil with 2-mercaptobenzimidazole and then with 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride, and then the modified soybean oil diethanolamide is synthesized by reacting the modified soybean oil with diethanolamine, which is used as a functional chain extender, and the modified polyurethane solution is prepared by polymerizing polytetramethylene ether glycol 2000, isophorone diisocyanate, and diol ultraviolet absorber, and then the functional polyurethane fiber is prepared by wet spinning; the flame-retardant high-elasticity fabric is prepared by blending the functional polyurethane fiber with the flame-retardant aramid fiber in a certain proportion and then performing post-treatment.
[0024] Firstly, the renewable resource soybean oil is used as raw material, which is grafted with 2-mercaptobenzimidazole by ultraviolet light initiation, and then the 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride hindered phenol structural unit is introduced accurately, and the hindered phenol functional side chain is constructed in the benzimidazole structure; the significant synergistic effect of antioxidant performance is realized, the benzimidazole and the hindered phenol structure synergistically work together to efficiently quench free radicals by providing hydrogen atoms, which greatly improves the heat-oxidative degradation resistance of the fiber material; the modified soybean oil diethanolamide prepared therefrom is used as a chain extender to participate in the synthesis of polyurethane, which introduces intrinsic antioxidant function into the fiber; meanwhile, the diol ultraviolet absorber is added to the polymerization system, and the benzotriazole structure thereof can convert harmful ultraviolet light energy into harmless heat energy through an efficient photochromic mechanism, thereby providing the polyurethane fiber with durable and excellent ultraviolet resistance, which effectively prevents yellowing and aging of the material.
[0025] Secondly, by introducing a phosphorus-containing flame-retardant intermediate synthesized from m-phenylenediamine and phenylphosphonic dichloride as a third monomer into the meta-aramid main chain, the aramid fiber is endowed with intrinsic and durable structural flame-retardant properties; finally, the functionalized polyurethane fiber is blended with the flame-retardant aramid fiber to realize multifunctional synergy; the rigid skeleton of aramid provides high strength and high modulus, and assumes the main flame-retardant role; while the functionalized polyurethane contributes excellent resilience, as well as ultraviolet resistance brought by the diol ultraviolet absorber and antioxidant protection brought by the benzimidazole-hindered phenol structure, effectively prolonging the service life of the fabric; the two complement each other, and the prepared fabric comprehensively exhibits excellent properties of high elasticity, high strength, permanent flame retardance, ultraviolet resistance and antioxidant, meeting the stringent requirements of high-end protective clothing on comprehensive performance. DETAILED DESCRIPTION
[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0027] In order to more clearly illustrate the method provided by the present application, the following examples are used for detailed description.
[0028] Example 1
[0029] A preparation method of a flame-retardant high-elasticity fabric mainly includes the following preparation steps:
[0030] (1) Mix soybean oil, 2-mercaptobenzimidazole, a photoinitiator and ethanol according to a mass ratio of 1:6:0.05:10, stir at 25°C and 300r / min until completely dissolved, irradiate with 365nm ultraviolet light for 1h, remove ethanol by rotary evaporation, add 4 times of anhydrous N,N-dimethylformamide based on the mass of soybean oil, stir at 50°C and 200r / min for 0.5h, cool to 25°C, add 1.2 equivalents of sodium hydride relative to the benzimidazole unit in a nitrogen atmosphere, continue to stir for 1h, warm to 30°C, add 1.2 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit, continue to stir for 12h, quench by adding 4 drops of methanol, rotary evaporation, and washing to obtain modified soybean oil; mix diethanolamine and sodium methoxide according to a mass ratio of 1:0.01, stir at 70°C and 200r / min for 10min; add 0.8 parts of modified soybean oil based on the mass of diethanolamine, continue to stir at 100°C for 2h, dehydrate, and vacuum dry to obtain modified soybean oil diethanolamide;
[0031] (2) polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanol amide and dibutyl tin dilaurate were weighed according to the molar ratio of 1:0.3:4:2.7:0.0008; under the nitrogen atmosphere, the polytetramethylene ether glycol 2000, diol ultraviolet absorber and isophorone diisocyanate were mixed, stirred at 70℃ and 300r / min for 1h, cooled to 40℃, and then the dibutyl tin dilaurate and modified soybean oil diethanol amide were added, and the stirring was continued for 5h to prepare a modified polyurethane solution; the prepared modified polyurethane solution was degassed and filtered, extruded into a 40wt% dimethyl carbonate aqueous solution through a spinneret for wet spinning, and then drawn, dried and wound to prepare a functionalized polyurethane fiber;
[0032] (3) under the protection of nitrogen, m-phenylenediamine, triethylamine and anhydrous acetonitrile were mixed according to the mass ratio of 1:0.7:4, stirred at 25℃ and 200r / min for 10min to obtain a m-phenylenediamine solution; phenyl phosphinic dichloride was weighed in an amount of 0.3 times the molar amount of m-phenylenediamine, and then dissolved in anhydrous acetonitrile to obtain a phenyl phosphinic dichloride solution at 20wt%; the phenyl phosphinic dichloride solution was added dropwise into the m-phenylenediamine solution under the conditions of 0℃ and 200r / min stirring for 1h, and then the temperature was increased to 25℃ and the reaction was continued for 10h; after filtration, rotary evaporation and ice water washing, a flame-retardant intermediate was prepared; under the nitrogen atmosphere, the m-phenylenediamine and the flame-retardant intermediate were mixed according to the molar ratio of 1:0.01, and then the mixture was added into N,N-dimethylacetamide at 20wt% and stirred at 25℃ and 200r / min until completely dissolved; the temperature was then decreased to-15℃, and 1.01 times the molar amount of m-phenylenediamine was added dropwise; the temperature was increased to 50℃, and the stirring was continued for 1h; during the reaction, the pH of the system was controlled to be 7 by using a saturated calcium hydroxide solution to prepare a modified aramid spinning solution; the modified aramid spinning solution was extruded into a 50wt% N,N-dimethylacetamide aqueous solution coagulation bath through a spinneret for wet spinning, and then drawn, dried and wound to prepare a flame-retardant aramid fiber;
[0033] (4) the functionalized polyurethane fiber and the flame-retardant aramid fiber were blended at a ratio of 1:3 to form an elastic yarn with a double-strand structure having a fineness of 12.5tex×2 and a twist of 70T / m; the elastic yarn was knitted into a plain fabric on a multifunctional flat knitting machine, with a warp density of 320 and a weft density of 250 roots / 10cm, and a thickness of 0.6±0.04mm; after singeing, continuous boiling, drying and calendering, a flame-retardant high-elasticity fabric was prepared.
[0034] Example 2:
[0035] A method for preparing a flame-retardant high-elasticity fabric mainly includes the following preparation steps:
[0036] (1) soybean oil, 2-mercapto benzimidazole, photoinitiator and ethanol were mixed in a mass ratio of 1:8:0.06:20, stirred at 27°C and 400 r / min until completely dissolved, irradiated with 365 nm ultraviolet light for 2 h, and the ethanol was removed by rotary evaporation. 6 times the amount of anhydrous N,N-dimethylformamide was added based on the mass of the soybean oil, and stirred at 60°C and 300 r / min for 1 h. The temperature was lowered to 27°C, and 1.3 equivalents of sodium hydride relative to the benzimidazole unit were added in a nitrogen atmosphere. Stirring was continued for 1.5 h, the temperature was raised to 40°C, and 1.35 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit were added. Stirring was continued for 24 h, 5 drops of methanol were added dropwise to quench, and rotary evaporation was performed. Washing was performed to obtain modified soybean oil; diethanolamine and sodium methoxide were mixed in a mass ratio of 1:0.02 and stirred at 80°C and 300 r / min for 20 min. 1 part of the modified soybean oil was added based on the mass of the diethanolamine, and stirring was continued at 120°C for 4 h. Dehydration and vacuum drying were performed to obtain modified soybean oil diethanolamide;
[0037] (2) polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanolamide, and dibutyltin dilaurate were weighed in a molar ratio of 1:0.3:4:2.7:0.001; in a nitrogen atmosphere, polytetramethylene ether glycol 2000, diol ultraviolet absorber, and isophorone diisocyanate were mixed, stirred at 80°C and 400 r / min for 2 h, the temperature was lowered to 60°C, dibutyltin dilaurate and modified soybean oil diethanolamide were added, and stirring was continued for 7 h to obtain a modified polyurethane solution; the prepared modified polyurethane solution was degassed and filtered, extruded into a 45 wt% aqueous dimethyl carbonate solution through a spinneret to perform wet spinning, and then drawn, dried, and wound to obtain functional polyurethane fibers;
[0038] (3) under the protection of nitrogen, mixing m-phenylenediamine, triethylamine and anhydrous acetonitrile according to the mass ratio of 1:0.9:5, stirring at 27℃, 300r / min for 20min to obtain m-phenylenediamine solution; weighing 0.35 times of phenyl phosphinic dichloride relative to the molar amount of m-phenylenediamine, and dissolving it in anhydrous acetonitrile to obtain a phenyl phosphinic dichloride solution with a concentration of 25wt%; under the condition of 3℃, 300r / min stirring, the phenyl phosphinic dichloride solution is added dropwise into the m-phenylenediamine solution and reacted for 2h, then the temperature is raised to 27℃ and the reaction is continued for 12h, then filtered, rotary evaporated, and washed with ice water to obtain a flame-retardant intermediate; mixing m-phenylenediamine and the flame-retardant intermediate according to the molar ratio of 1:0.03, then adding the mixture into N,N-dimethylacetamide with a concentration of 25wt% at 27℃, 300r / min stirring until completely dissolved, cooling to-12℃, adding 1.03 times of isophthaloyl chloride relative to the molar amount of m-phenylenediamine, raising the temperature to 60℃, and continuing to stir for 2h, during which the pH of the system is controlled to 7 with saturated calcium hydroxide solution to obtain a modified aramid spinning solution; the modified aramid spinning solution is extruded through the spinneret into a 53wt% N,N-dimethylacetamide aqueous solution coagulation bath for wet spinning, and then drawn, dried and wound to obtain flame-retardant aramid fiber;
[0039] (4) mixing the functionalized polyurethane fiber and the flame-retardant aramid fiber according to the ratio of 1:3 to form an elastic yarn with a fineness of 12.5texx2 and a twist of 70T / m in a double-strand structure; weaving a plain fabric with a warp density of 320 and a weft density of 250, a thickness of 0.6±0.04mm on a multifunctional flat knitting machine, and then singeing, continuous boiling, drying, and calendering to obtain a flame-retardant high-elasticity fabric.
[0040] Example 3:
[0041] A method for preparing a flame-retardant high-elasticity fabric, mainly comprising the following preparation steps:
[0042] (1) soybean oil, 2-mercapto benzimidazole, photoinitiator and ethanol were mixed in a mass ratio of 1:10:0.07:30, stirred at 30°C and 500 r / min until completely dissolved, irradiated with 365 nm ultraviolet light for 3h, and the ethanol was removed by rotary evaporation. 8 times anhydrous N,N-dimethylformamide was added based on the mass of the soybean oil, stirred at 70°C and 400 r / min for 1.5h, cooled to 30°C, and 1.5 equivalents of sodium hydride relative to the benzimidazole unit was added in a nitrogen atmosphere, and continued to stir for 2h. The temperature was raised to 50°C, 1.5 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit was added, and continued to stir for 48h. 5 drops of methanol were added dropwise to quench, rotary evaporation, and washing to obtain a modified soybean oil; diethanolamine and sodium methoxide were mixed in a mass ratio of 1:0.03 and stirred at 90°C and 400 r / min for 30min. 1.2 parts of the modified soybean oil was added based on the mass of the diethanolamine, and continued to stir at 140°C for 6h, dehydrated, and vacuum dried to obtain a modified soybean oil diethanolamide;
[0043] (2) polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanolamide and dibutyltin dilaurate were weighed in a molar ratio of 1:0.3:4:2.7:0.0012; in a nitrogen atmosphere, polytetramethylene ether glycol 2000, diol ultraviolet absorber and isophorone diisocyanate were mixed, stirred at 90°C and 500 r / min for 3h, cooled to 80°C, and dibutyltin dilaurate and modified soybean oil diethanolamide were added, and continued to stir for 9h to obtain a modified polyurethane solution; the prepared modified polyurethane solution was degassed and filtered, extruded into a 50wt% aqueous dimethyl carbonate solution through a spinneret for wet spinning, and then drawn, dried and wound to obtain a functional polyurethane fiber;
[0044] (3) Under the protection of nitrogen, m-phenylenediamine, triethylamine and anhydrous acetonitrile were mixed in a mass ratio of 1:1.1:6, stirred at 30°C and 400 r / min for 30 min to obtain a m-phenylenediamine solution; 0.4 times of phenyl phosphinic dichloride relative to the molar amount of m-phenylenediamine was weighed and dissolved in anhydrous acetonitrile to obtain a phenyl phosphinic dichloride solution at 30 wt%; the phenyl phosphinic dichloride solution was added dropwise into the m-phenylenediamine solution under the condition of stirring at 5°C and 400 r / min for 3 h, and then the temperature was increased to 30°C and the reaction was continued for 14 h; filtration, rotary evaporation, and ice water washing were performed to obtain a flame-retardant intermediate; the m-phenylenediamine and the flame-retardant intermediate were mixed in a molar ratio of 1:0.05 under a nitrogen atmosphere, and then the mixture was added into N,N-dimethylacetamide at 30 wt% to be completely dissolved under stirring at 30°C and 400 r / min; the temperature was decreased to -10°C, and 1.05 times of isophthaloyl chloride relative to the molar amount of m-phenylenediamine was added dropwise; the temperature was increased to 70°C, and the stirring was continued for 3 h; during the stirring, the pH of the system was controlled to be 7 by using a saturated calcium hydroxide solution to obtain a modified aramid spinning solution; the modified aramid spinning solution was extruded through a spinneret into a 55 wt% N,N-dimethylacetamide aqueous solution coagulation bath for wet spinning, and then drawn, dried, and wound to obtain a flame-retardant aramid fiber;
[0045] (4) The functionalized polyurethane fiber and the flame-retardant aramid fiber were blended in a ratio of 1:3 to form an elastic yarn with a double-strand structure having a fineness of 12.5 tex x 2 and a twist of 70 T / m; the elastic yarn was knitted on a multifunctional flat knitting machine to form a plain fabric with a warp density of 320 and a weft density of 250 per 10 cm and a thickness of 0.6 ± 0.04 mm; after singeing, continuous boiling, drying, and calendering, a flame-retardant high-elasticity fabric was obtained.
[0046] Comparative Example 1
[0047] A method for preparing a flame-retardant high-elasticity fabric mainly includes the following preparation steps:
[0048] (1) Soybean oil, 2-mercaptobenzimidazole, a photoinitiator, and ethanol were mixed in a mass ratio of 1:8:0.06:20, and stirred at 27°C and 400 r / min until completely dissolved; 365 nm ultraviolet irradiation was performed for 2 h; ethanol was removed by rotary evaporation; and washing was performed to obtain a modified soybean oil; diethanolamine and sodium methoxide were mixed in a mass ratio of 1:0.02, and stirred at 80°C and 300 r / min for 20 min; 1 part of the modified soybean oil was added based on the mass of diethanolamine; the stirring was continued at 120°C for 4 h; dehydration was performed; and vacuum drying was performed to obtain a modified soybean oil diethanolamide;
[0049] (2) polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanol amide and dibutyl tin dilaurate were weighed according to a molar ratio of 1:0.3:4:2.7:0.001; under a nitrogen atmosphere, the polytetramethylene ether glycol 2000, diol ultraviolet absorber and isophorone diisocyanate were mixed, stirred at 80°C and 400 r / min for 2h, cooled to 60°C, and then dibutyl tin dilaurate and modified soybean oil diethanol amide were added, and the stirring was continued for 7h to prepare a modified polyurethane solution; the prepared modified polyurethane solution was degassed and filtered, extruded into a 45wt% dimethyl carbonate aqueous solution through a spinneret for wet spinning, and then drawn, dried and wound to prepare a functional polyurethane fiber;
[0050] (3) under nitrogen protection, m-phenylenediamine, triethylamine and anhydrous acetonitrile were mixed according to a mass ratio of 1:0.9:5, stirred at 27°C and 300 r / min for 20 min to obtain a m-phenylenediamine solution; phenyl phosphinic dichloride was weighed at 0.35 times the molar amount of m-phenylenediamine, and then dissolved in anhydrous acetonitrile at 25wt% to obtain a phenyl phosphinic dichloride solution; the phenyl phosphinic dichloride solution was added dropwise into the m-phenylenediamine solution under stirring at 3°C and 300 r / min for 2h, and then the temperature was raised to 27°C for continuous reaction for 12h, followed by filtration, rotary evaporation, ice water washing to obtain a flame-retardant intermediate; under a nitrogen atmosphere, m-phenylenediamine and the flame-retardant intermediate were mixed according to a molar ratio of 1:0.03, and then the mixture was added into N,N-dimethylacetamide at 25wt%, stirred at 27°C and 300 r / min until completely dissolved, cooled to-12°C, and then 1.03 times the molar amount of m-phthaloyl chloride relative to m-phenylenediamine was added dropwise, the temperature was raised to 60°C, and the stirring was continued for 2h, during which the pH of the system was controlled to be 7 with saturated calcium hydroxide solution to obtain a modified aramid spinning solution; the modified aramid spinning solution was extruded into a 53wt% N,N-dimethylacetamide aqueous solution coagulation bath through a spinneret for wet spinning, and then drawn, dried and wound to obtain a flame-retardant aramid fiber;
[0051] (4) the functional polyurethane fiber and the flame-retardant aramid fiber were blended at a ratio of 1:3 into a two-strand structure elastic yarn with a fineness of 12.5texx2 and a twist of 70T / m; the elastic yarn was knitted into a plain fabric with a warp density of 320 and a weft density of 250 per 10 cm, and a thickness of 0.6±0.04mm on a multifunctional flat knitting machine, and then singeing, continuous boiling, drying, calendering were performed to obtain a flame-retardant high-elasticity fabric.
[0052] Comparative Example 2
[0053] A preparation method of a flame-retardant high-elasticity fabric mainly includes the following preparation steps:
[0054] (1) mixing diethanolamine and sodium methoxide according to the mass ratio of 1:0.02, stirring at 80°C and 300 r / min for 20 min; adding 1 part of soybean oil based on the mass of diethanolamine, continuing to stir at 120°C for 4 h, dehydrating, and vacuum drying to prepare soybean oil diethanolamide;
[0055] (2) taking polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanolamide, and dibutyltin dilaurate according to the molar ratio of 1:0.3:4:2.7:0.001; in a nitrogen atmosphere, mixing polytetramethylene ether glycol 2000, diol ultraviolet absorber, and isophorone diisocyanate, stirring at 80°C and 400 r / min for 2 h, cooling to 60°C, adding dibutyltin dilaurate and soybean oil diethanolamide, and continuing to stir for 7 h to prepare a modified polyurethane solution; defoaming and filtering the prepared modified polyurethane solution, extruding it into a 45 wt% aqueous dimethyl carbonate solution through a spinneret to perform wet spinning, and performing drawing, drying, and winding to prepare functional polyurethane fibers;
[0056] (3) mixing m-phenylenediamine, triethylamine, and anhydrous acetonitrile according to the mass ratio of 1:0.9:5 under nitrogen protection, stirring at 27°C and 300 r / min for 20 min to obtain a m-phenylenediamine solution; taking phenyl phosphinic dichloride at 0.35 times the molar amount of m-phenylenediamine, and dissolving it in anhydrous acetonitrile at 25 wt% to obtain a phenyl phosphinic dichloride solution; adding the phenyl phosphinic dichloride solution dropwise into the m-phenylenediamine solution under stirring at 3°C and 300 r / min for 2 h, warming to 27°C and continuing to react for 12 h, filtering, rotary evaporation, and ice water washing to prepare a flame-retardant intermediate; mixing m-phenylenediamine and the flame-retardant intermediate according to the molar ratio of 1:0.03 in a nitrogen atmosphere, adding the mixture into N,N-dimethylacetamide at 25 wt%, stirring at 27°C and 300 r / min until complete dissolution, cooling to -12°C, adding m-phthaloyl chloride at 1.03 times the molar amount of m-phenylenediamine, warming to 60°C, and continuing to stir for 2 h, during which the pH of the system is controlled to be 7 with saturated calcium hydroxide solution to prepare a modified aramid spinning solution; extruding the modified aramid spinning solution into a 53 wt% N,N-dimethylacetamide aqueous solution coagulation bath through a spinneret to perform wet spinning, and performing drawing, drying, and winding to prepare flame-retardant aramid fibers;
[0057] (4) blending the functional polyurethane fibers and the flame-retardant aramid fibers at a ratio of 1:3 into an elastic yarn with a double-strand structure of 12.5 tex x 2 and a twist of 70 T / m; weaving a plain fabric with a warp density of 320 and a weft density of 250 roots / 10 cm and a thickness of 0.6±0.04 mm on a multifunctional flat knitting machine, and preparing a flame-retardant high-elasticity fabric after singeing, continuous boiling, drying, and calendering.
[0058] Comparative Example 3:
[0059] The application discloses a preparation method of a flame-retardant high-elasticity fabric.
[0060] (1) soybean oil, 2-mercaptobenzimidazole, a photoinitiator and ethanol are mixed according to a mass ratio of 1:8:0.06:20, stirring is carried out at 27 DEG C and 400 r / min until complete dissolution, 365 nm ultraviolet irradiation is carried out for 2 h, ethanol is removed by rotary evaporation, 6 times of anhydrous N,N-dimethylformamide is added based on the mass of the soybean oil, stirring is carried out at 60 DEG C and 300 r / min for 1 h, the temperature is lowered to 27 DEG C, 1.3 equivalents of sodium hydride relative to the benzimidazole unit are added in a nitrogen atmosphere, stirring is continued for 1.5 h, the temperature is raised to 40 DEG C, 1.35 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit are added, stirring is continued for 24 h, 5 drops of methanol are added dropwise for quenching, rotary evaporation is carried out, and washing is carried out to obtain modified soybean oil; diethanolamine and sodium methoxide are mixed according to a mass ratio of 1:0.02, stirring is carried out at 80 DEG C and 300 r / min for 20 min; 1 part of the modified soybean oil is added based on the mass of the diethanolamine, stirring is continued at 120 DEG C for 4 h, dehydration is carried out, and vacuum drying is carried out to obtain modified soybean oil diethanolamide;
[0061] (2) polytetramethylene ether glycol 2000, isophorone diisocyanate, modified soybean oil diethanolamide and dibutyltin dilaurate are weighed according to a molar ratio of 1:4:3:0.001; in a nitrogen atmosphere, the polytetramethylene ether glycol 2000 and the isophorone diisocyanate are mixed, stirring is carried out at 80 DEG C and 400 r / min for 2 h, the temperature is lowered to 60 DEG C, the dibutyltin dilaurate and the modified soybean oil diethanolamide are added, and stirring is continued for 7 h to obtain a modified polyurethane solution; the prepared modified polyurethane solution is degassed and filtered, is extruded into 45 wt% dimethyl carbonate aqueous solution through a spinneret for wet spinning, and is subjected to drawing, drying and winding to obtain functional polyurethane fibers;
[0062] (3) under the protection of nitrogen, mixing m-phenylenediamine, triethylamine and anhydrous acetonitrile according to the mass ratio of 1:0.9:5, stirring at 27°C, 300r / min for 20min to obtain m-phenylenediamine solution; weighing 0.35 times of phenyl phosphinic dichloride relative to the molar amount of m-phenylenediamine, and dissolving it in anhydrous acetonitrile to obtain a phenyl phosphinic dichloride solution with a concentration of 25wt%; under the condition of 3°C, 300r / min stirring, the phenyl phosphinic dichloride solution is added dropwise into the m-phenylenediamine solution and reacted for 2h, then the temperature is raised to 27°C and the reaction is continued for 12h, then filtered, rotary evaporated, and washed with ice water to obtain a flame-retardant intermediate; mixing m-phenylenediamine and the flame-retardant intermediate according to the molar ratio of 1:0.03, then adding the mixture into N,N-dimethylacetamide with a concentration of 25wt% at 27°C, 300r / min stirring until completely dissolved, cooling to-12°C, adding 1.03 times of isophthaloyl chloride relative to the molar amount of m-phenylenediamine, raising the temperature to 60°C, and continuing to stir for 2h, during which the pH of the system is controlled to 7 with saturated calcium hydroxide solution to obtain a modified aramid spinning solution; the modified aramid spinning solution is extruded through the spinneret into a 53wt% N,N-dimethylacetamide aqueous solution coagulation bath for wet spinning, and then drawn, dried and wound to obtain a flame-retardant aramid fiber;
[0063] (4) mixing the functionalized polyurethane fiber and the flame-retardant aramid fiber according to the ratio of 1:3 to form an elastic yarn with a fineness of 12.5texx2 and a twist of 70T / m in a double-strand structure; weaving a plain fabric with a warp density of 320 and a weft density of 250, a thickness of 0.6±0.04mm on a multifunctional flat knitting machine, and then singeing, continuous boiling, drying, and calendering to obtain a flame-retardant high-elasticity fabric.
[0064] Comparative Example 4:
[0065] A method for preparing a flame-retardant high-elasticity fabric, mainly comprising the following preparation steps:
[0066] (1) soybean oil, 2-mercapto benzimidazole, photoinitiator and ethanol were mixed in a mass ratio of 1:8:0.06:20, stirred at 27°C and 400 r / min until completely dissolved, irradiated with 365 nm ultraviolet light for 2 h, and the ethanol was removed by rotary evaporation. 6 times the amount of anhydrous N,N-dimethylformamide was added based on the mass of the soybean oil, stirred at 60°C and 300 r / min for 1 h, cooled to 27°C, and 1.3 equivalents of sodium hydride relative to the benzimidazole unit was added in a nitrogen atmosphere. Stirring was continued for 1.5 h, the temperature was raised to 40°C, 1.35 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit was added, and stirring was continued for 24 h. 5 drops of methanol were added dropwise to quench the reaction, and the modified soybean oil was obtained by rotary evaporation and washing. Diethanolamine and sodium methoxide were mixed in a mass ratio of 1:0.02 and stirred at 80°C and 300 r / min for 20 min. 1 part of the modified soybean oil was added based on the mass of the diethanolamine, and stirring was continued at 120°C for 4 h. The modified soybean oil diethanolamide was obtained by dehydration and vacuum drying.
[0067] (2) Polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanolamide, and dibutyltin dilaurate were weighed in a molar ratio of 1:0.3:4:2.7:0.001. In a nitrogen atmosphere, polytetramethylene ether glycol 2000, diol ultraviolet absorber, and isophorone diisocyanate were mixed, stirred at 80°C and 400 r / min for 2 h, cooled to 60°C, and dibutyltin dilaurate and modified soybean oil diethanolamide were added. Stirring was continued for 7 h to obtain a modified polyurethane solution. The prepared modified polyurethane solution was degassed and filtered, extruded through a spinneret into a 45 wt% aqueous dimethyl carbonate solution for wet spinning, and then drawn, dried, and wound to obtain functionalized polyurethane fibers.
[0068] (3) In a nitrogen atmosphere, m-phenylenediamine, triethylamine, and anhydrous acetonitrile were mixed in a mass ratio of 1:0.9:5 and stirred at 27°C and 300 r / min for 20 min to obtain a m-phenylenediamine solution. Phenylphosphonic dichloride was weighed in a molar amount of 0.35 times that of m-phenylenediamine and dissolved in anhydrous acetonitrile to obtain a phenylphosphonic dichloride solution at 25 wt%. Under stirring conditions at 3°C and 300 r / min, 0.03 times the molar amount of the phenylphosphonic dichloride solution and 1.03 times the molar amount of isophthaloyl chloride were added dropwise simultaneously. The temperature was raised to 27°C and reacted for 12 h, and then the temperature was raised to 60°C and stirred for 2 h. During this period, the pH of the system was controlled at 7 with saturated calcium hydroxide solution to obtain a modified aramid spinning solution. The modified aramid spinning solution was extruded through a spinneret into a 53 wt% aqueous N,N-dimethylacetamide coagulation bath for wet spinning, and then drawn, dried, and wound to obtain a flame-retardant aramid fiber.
[0069] (4) The functional polyurethane fiber is blended with the flame-retardant aramid fiber at a ratio of 1:3 to form an elastic yarn with a fineness of 12.5 tex x 2 and a twist of 70 T / m in a double-strand structure; the elastic yarn is knitted into a plain fabric with a warp density of 320 and a weft density of 250 per 10 cm and a thickness of 0.6 ± 0.04 mm on a multifunctional flat knitting machine; and the flame-retardant high-elasticity fabric is obtained after singeing, continuous boiling, drying and calendering.
[0070] Comparative Example 5
[0071] A preparation method of a flame-retardant high-elasticity fabric mainly includes the following preparation steps:
[0072] (1) Soybean oil, 2-mercaptobenzimidazole, a photoinitiator and ethanol are mixed at a mass ratio of 1:8:0.06:20, stirred at 27°C and 400 r / min until completely dissolved, irradiated with 365 nm ultraviolet light for 2 h, and then rotary evaporated to remove ethanol; 6 times of anhydrous N,N-dimethylformamide is added based on the mass of the soybean oil, stirred at 60°C and 300 r / min for 1 h, cooled to 27°C, and then 1.3 equivalents of sodium hydride relative to the benzimidazole unit is added in a nitrogen atmosphere, and the stirring is continued for 1.5 h; the temperature is raised to 40°C, 1.35 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit is added, and the stirring is continued for 24 h; 5 drops of methanol is added dropwise for quenching, rotary evaporated, and washed to obtain modified soybean oil; diethanolamine and sodium methoxide are mixed at a mass ratio of 1:0.02, stirred at 80°C and 300 r / min for 20 min; 1 part of the modified soybean oil is added based on the mass of the diethanolamine, and the stirring is continued at 120°C for 4 h, dehydrated, and vacuum dried to obtain modified soybean oil diethanolamide;
[0073] (2) Polytetramethylene ether glycol 2000, diol ultraviolet absorber, isophorone diisocyanate, modified soybean oil diethanolamide and dibutyltin dilaurate are weighed at a molar ratio of 1:0.3:4:2.7:0.001; in a nitrogen atmosphere, the polytetramethylene ether glycol 2000, diol ultraviolet absorber and isophorone diisocyanate are mixed, stirred at 80°C and 400 r / min for 2 h, cooled to 60°C, and then the dibutyltin dilaurate and the modified soybean oil diethanolamide are added, and the stirring is continued for 7 h to obtain a modified polyurethane solution; the prepared modified polyurethane solution is degassed and filtered, extruded into a 45 wt% aqueous dimethyl carbonate solution through a spinneret for wet spinning, and then subjected to drawing, drying and winding to obtain a functional polyurethane fiber;
[0074] (3) under the protection of nitrogen, m-phenylenediamine is added to N,N-dimethylacetamide at 25wt%, stirred at 27°C and 300r / min until completely dissolved, cooled to-12°C, drop 1 times of isophthaloyl chloride relative to the molar amount of m-phenylenediamine, warmed to 60°C, continue to stir for 2h, control the pH of the system to 7 with saturated calcium hydroxide solution during the period, to prepare a modified aramid spinning solution; the modified aramid spinning solution is extruded into a 53wt% N,N-dimethylacetamide aqueous solution coagulation bath through the spinneret to spin by wet spinning, drawn, dried and wound to prepare aramid fiber;
[0075] (4) the functional polyurethane fiber and the flame-retardant aramid fiber are blended at 1:3 to form an elastic yarn with a fineness of 12.5texx2 and a twist of 70T / m in a double-strand structure; the elastic yarn is knitted into a plain fabric with a warp density of 320 and a weft density of 250 per 10cm and a thickness of 0.6±0.04mm on a multifunctional flat knitting machine, and a flame-retardant high-elasticity fabric is prepared after singeing, continuous boiling, drying and calendering.
[0076] Comparative Example 6:
[0077] A method for preparing a flame-retardant high-elasticity fabric mainly includes the following preparation steps:
[0078] (1) under the protection of nitrogen, m-phenylenediamine, triethylamine and anhydrous acetonitrile are mixed at a mass ratio of 1:0.9:5, stirred at 27°C and 300r / min for 20min to obtain a m-phenylenediamine solution; phenyl phosphinic dichloride is weighed at 0.35 times relative to the molar amount of m-phenylenediamine, and dissolved in anhydrous acetonitrile at 25wt% to obtain a phenyl phosphinic dichloride solution; the phenyl phosphinic dichloride solution is added dropwise to the m-phenylenediamine solution under the condition of 3°C and 300r / min stirring for 2h, and then the temperature is raised to 27°C for continuous reaction for 12h, followed by filtration, rotary evaporation and ice water washing to obtain a flame-retardant intermediate; under the nitrogen atmosphere, m-phenylenediamine and the flame-retardant intermediate are mixed at a molar ratio of 1:0.03, and then the mixture is added to N,N-dimethylacetamide at 25wt%, stirred at 27°C and 300r / min until completely dissolved, cooled to-12°C, drop 1.03 times of isophthaloyl chloride relative to the molar amount of m-phenylenediamine, warmed to 60°C, continue to stir for 2h, control the pH of the system to 7 with saturated calcium hydroxide solution during the period, to prepare a modified aramid spinning solution; the modified aramid spinning solution is extruded into a 53wt% N,N-dimethylacetamide aqueous solution coagulation bath through the spinneret to spin by wet spinning, drawn, dried and wound to prepare a flame-retardant aramid fiber;
[0079] (4) The functional polyurethane fiber is blended with the flame-retardant aramid fiber at 1:3 to form an elastic yarn with a fineness of 12.5 tex x 2 and a twist of 70 T / m in a double-strand line structure; the elastic yarn is knitted into a plain fabric with a warp and weft density of 320 x 250 roots / 10 cm and a thickness of 0.6 ± 0.04 mm on a multifunctional flat knitting machine, and a flame-retardant high-elasticity fabric is prepared after singeing, continuous boiling, drying and calendering.
[0080] Test Example 1
[0081] Test of flame-retardant property, elasticity, ultraviolet resistance, thermal-oxidative aging resistance and breaking strength
[0082] Test method of flame-retardant property: the flame-retardant high-elasticity fabric obtained in each example and the fabric of the comparative example are tested for limiting oxygen index according to GB / T5454-1997 “Textile Burning Property Test Oxygen Index Method”,
[0083] Test method of fabric elasticity: the flame-retardant high-elasticity fabric obtained in each example and the fabric of the comparative example are tested for fabric elasticity recovery rate according to FZ / T70006-2022 “Knitted Fabric Tensile Elasticity Recovery Rate Test Method” using a YG026H fabric strength machine.
[0084] Test method of ultraviolet resistance: the flame-retardant high-elasticity fabric obtained in each example and the fabric of the comparative example are tested for ultraviolet resistance according to GB / T18830-2009 “Evaluation of Anti-Ultraviolet Property of Textiles”.
[0085] Test method of thermal-oxidative aging resistance: the flame-retardant high-elasticity fabric obtained in each example and the fabric of the comparative example are placed in an oven at 90℃, and the elasticity recovery rate is tested according to FZ / T70006-2022 “Knitted Fabric Tensile Elasticity Recovery Rate Test Method” after aging for 48 h.
[0086] Test method of tensile strength: the flame-retardant high-elasticity fabric obtained in each example and the fabric of the comparative example are tested for tensile strength according to GB / T3923.1-2013 “Textile Fabric Tensile Property Part 1” with a tensile speed of 100 mm / min.
[0087] The results are shown in Table 1.
[0088] Table 1
[0089]
[0090]
[0091] It can be found from the experimental data of Examples 1-3 and Comparative Examples 1-6 in Table 1 that the flame-retardant high-elasticity fabric prepared in the present application has good flame-retardant property, elasticity, ultraviolet resistance, thermal-oxidative aging resistance and breaking strength.
[0092] It can be found by comparing Example 1-3 and Comparative Example 1 that the elastic recovery rate of Comparative Example 1 after aging is significantly reduced, which shows that the hindered phenol structure 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl chloride grafted in the modified soybean oil can effectively capture and eliminate free radicals generated during thermal oxidative aging, interrupt the degradation chain reaction of polymer chains, and thus significantly improve the thermal oxidative aging resistance of the final fabric.
[0093] It can be found by comparing Comparative Example 1 and Comparative Example 2 that the rebound performance of Comparative Example 1 after thermal aging is significantly reduced, which shows that relying solely on the benzimidazole structure can provide certain primary antioxidant effect, but its ability to stabilize free radicals is limited, while the hindered phenol structure 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl chloride grafted can more efficiently capture and eliminate macromolecular free radicals generated during thermal oxidative aging by providing more steric hindered phenolic hydroxyl groups, and has a synergistic antioxidant effect with the benzimidazole structure, thereby significantly enhancing the long-term thermal oxidative aging stability of the material as a whole.
[0094] It can be found by comparing Example 1-3 and Comparative Example 3 that the diol ultraviolet absorber 2-[3'-(2H-benzotriazole)-5'-tert-butyl-4'-hydroxy-phenyl]-2-ethylpropane-1,3- propanediol added during the synthesis of polyurethane can efficiently absorb ultraviolet light and convert it into harmless heat energy, thereby effectively preventing the destruction of the polyurethane molecular chain by ultraviolet light and significantly enhancing the ultraviolet resistance of the final fabric.
[0095] It can be found by comparing Example 1-3 and Comparative Example 4 that the limiting oxygen index of the aramid fabric prepared by one-pot method in Comparative Example 4 is significantly reduced and the breaking strength is also reduced, which shows that the method of preparing the diamine flame-retardant intermediate first and then participating in polymerization in the original scheme can ensure that the phenyl phosphine dichloride selectively reacts with p-phenylenediamine to form a regular diamine monomer containing a phosphorus-based flame-retardant unit, thereby achieving uniform and stable embedding of the flame-retardant element in the aramid polymer molecular chain. The one-pot method causes the phenyl phosphine dichloride to compete with p-phenylenediamine chloride to react with p-phenylenediamine, resulting in a phosphorus content in the aramid macromolecular structure that is much lower than the theoretical value, and causing the regularity of the molecular chain structure to be destroyed, the distribution of the flame-retardant groups to be uneven, and part of the active amine groups to be prematurely consumed. This not only severely affects the molecular weight and crystallinity of the polymer, resulting in a reduction in breaking strength, but also significantly reduces the efficiency of the phosphorus-based flame retardant, ultimately leading to deterioration of the flame-retardant performance of the fabric.
[0096] It can be found by comparing Examples 1-3 and Comparative Example 5 that the limiting oxygen index of the aramid fiber modified by copolymerization of the diamine flame-retardant monomer is significantly improved, which indicates that the phosphorus-nitrogen synergistic effect formed by the introduction of the phosphorus-containing flame-retardant monomer during the aramid polymerization process can promote the formation of a dense carbon layer on the fiber surface during combustion to play a condensed phase barrier role, and can also release phosphorus-containing free radicals to capture gas phase free radicals to interrupt the combustion reaction, thereby greatly improving the flame-retardant performance.
[0097] It can be found by comparing Examples 1-3 and Comparative Example 6 that the elastic recovery rate of the fabric prepared by using only flame-retardant aramid is low, which indicates that the micro-phase separation structure formed by the polytetramethylene ether glycol soft segment and isophorone diisocyanate hard segment in the molecular chain of the functional polyurethane fiber can provide excellent high elasticity and rebound force, and after blending with flame-retardant aramid fiber at a ratio of 1:3, the reversible stretching / recovery characteristics of the polyurethane molecular chain and the rigid support of aramid form a complementary system, when the fabric is stretched by external force, the polyurethane fiber absorbs energy and provides ductility through molecular chain orientation and rearrangement of hydrogen bond network, and after the external force is removed, it can also restore to the original state through the memory effect of the micro-phase separation structure, thereby significantly improving the elastic performance of the final fabric.
[0098] It is apparent to those skilled in the art that the present application is not limited to the details of the foregoing exemplary embodiments, and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and not restrictive, and the scope of the present application should be defined by the appended claims rather than the above description, and it is intended to encompass all changes falling within the meaning and range of equivalents of the claims. Any mark in the claims should not be considered as limiting the involved claims.
Claims
1. A flame-retardant, highly elastic fabric, characterized in that, The flame-retardant high-elasticity fabric is made by blending functionalized polyurethane fibers and modified aramid fibers in a certain proportion and then performing post-treatment.
2. The flame-retardant high-elasticity fabric according to claim 1, characterized in that, The functionalized polyurethane fiber is prepared by wet spinning after stepwise polymerization of polytetramethylene ether glycol 2000, isophorone diisocyanate, diol UV absorber and modified soybean oil diethanolamide.
3. The flame-retardant high-elasticity fabric according to claim 2, characterized in that, The modified soybean oil diethanolamide is prepared by photoinitiating the grafting of soybean oil with 2-mercaptobenzimidazole and reacting it with 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride, followed by amidation with diethanolamine.
4. The flame-retardant high-elasticity fabric according to claim 1, characterized in that, The modified aramid fiber is prepared by condensing m-phenylenediamine and phenylphosphonodichloride to synthesize a flame-retardant intermediate, which is then involved in the meta-aramid polymerization.
5. A method for preparing a flame-retardant, highly elastic fabric, characterized in that, The preparation steps include the following: (1) Mix soybean oil, 2-mercaptobenzimidazole, photoinitiator, and ethanol at a mass ratio of 1:(6-10):(0.05-0.07):(10-30), stir at 25-30℃ and 300-500 r / min until completely dissolved, irradiate with 365 nm ultraviolet light for 1-3 h, remove ethanol by rotary evaporation, add 4-8 times the mass of anhydrous N,N-dimethylformamide based on the weight of soybean oil, stir at 50-70℃ and 200-400 r / min for 0.5-1.5 h, cool to 25-30℃, add sodium hydride in a nitrogen atmosphere at an amount of 1.2-1.5 equivalents relative to the benzimidazole unit, and continue stirring for 1-3 h. After 2 hours, the temperature was raised to 30–50°C, and 1.2–1.5 equivalents of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride relative to the benzimidazole unit were added. The mixture was stirred for 12–48 hours, and 4–5 drops of methanol were added dropwise to quench the mixture. The mixture was then rotary evaporated and washed to obtain modified soybean oil. Diethanolamine and sodium methoxide were mixed at a mass ratio of 1:0.01–0.03 and stirred at 70–90°C and 200–400 r / min for 10–30 min. 0.8–1.2 parts of modified soybean oil were added based on the mass of diethanolamine, and the mixture was stirred at 100–140°C for 2–6 hours. The mixture was then dehydrated and vacuum dried to obtain modified soybean oil diethanolamide. (2) Weigh out polytetramethylene ether glycol 2000, glycol UV absorber, isophorone diisocyanate, modified soybean oil diethanolamide and dibutyltin dilaurate in a molar ratio of 1:0.3:4:2.7:(0.0008~0.0012); mix polytetramethylene ether glycol 2000, glycol UV absorber and isophorone diisocyanate in a nitrogen atmosphere, stir at 70~90℃ and 300~500r / min for 1~3h, cool down to 40~80℃, add dibutyltin dilaurate and modified soybean oil diethanolamide, continue stirring for 5~9h to obtain a modified polyurethane solution; degas and filter the prepared modified polyurethane solution, extrude it through the spinneret into a 40~50wt% dimethyl carbonate aqueous solution for wet spinning, and then draw, dry and wind to obtain functionalized polyurethane fiber; (3) Under nitrogen protection, m-phenylenediamine, triethylamine, and anhydrous acetonitrile are mixed at a mass ratio of 1:(0.7-1.1):(4-6) and stirred at 25-30℃ and 200-400 r / min for 10-30 min to obtain a m-phenylenediamine solution; phenylphosphonic dichloride is weighed at a molar weight relative to m-phenylenediamine and dissolved in anhydrous acetonitrile at 20-30 wt% to obtain a phenylphosphonic dichloride solution; the phenylphosphonic dichloride solution is added dropwise to the m-phenylenediamine solution under stirring at 0-5℃ and 200-400 r / min for 1-3 h, the temperature is raised to 25-30℃ and the reaction continues for 10-14 h, filtered, rotary evaporated, and washed with ice water to obtain a flame-retardant intermediate; under a nitrogen atmosphere, m-phenylenediamine is added to the solution... After mixing diamine and flame-retardant intermediates at a molar ratio of 1:0.01–0.05, 20–30 wt% of the mixture is added to N,N-dimethylacetamide. The mixture is stirred at 25–30 °C and 200–400 r / min until completely dissolved. The temperature is then lowered to -15–-10 °C, and isophthaloyl chloride is added dropwise at 1.01–1.05 times the molar amount of m-phenylenediamine. The temperature is then raised to 50–70 °C, and stirring is continued for 1–3 h. During this period, the pH of the system is controlled at 7–8 using a saturated calcium hydroxide solution to obtain a modified aramid spinning solution. The modified aramid spinning solution is then extruded through a spinneret into a coagulation bath containing 50–55 wt% N,N-dimethylacetamide aqueous solution for wet spinning. After drawing, drying, and winding, flame-retardant aramid fibers are obtained. (4) Functionalized polyurethane fiber and flame-retardant aramid fiber are blended at a ratio of 1:3 to form a double-strand elastic yarn with a fineness of 12.5tex×2 and a twist of 70T / m; the elastic yarn is woven on a multi-functional flat knitting machine and then finished to obtain a flame-retardant high elastic fabric.
6. The method for preparing a flame-retardant high-elasticity fabric according to claim 5, characterized in that, The preparation method of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl chloride in step (1) is as follows: 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid is dissolved in thionyl chloride at 20-30 wt%, stirred and refluxed at 25-30℃ and 300-500 r / min for 2-4 h, and then evaporated under reduced pressure to prepare the product.
7. The method for preparing a flame-retardant high-elasticity fabric according to claim 5, characterized in that, The diol UV absorber mentioned in step (2) is 2-[3'-(2H-benzotriazole)-5'-tert-butyl-4'-hydroxy-phenyl]-2-ethylpropane-1,3-propanediol, which is of analytical grade.
8. The method for preparing a flame-retardant high-elasticity fabric according to claim 5, characterized in that, The main spinning process in step (2) is as follows: the spinneret is a 0.1mm diameter × 30mm round hole, the spinneret speed is 0.5mL / min, the coagulation bath temperature is maintained at 20~25℃, the obtained nascent fiber is washed with water, stretched 2.5 times in a 50℃ hot water bath, and dried at 80~100℃.
9. The method for preparing a flame-retardant high-elasticity fabric according to claim 5, characterized in that, The main spinning process in step (3) is as follows: the spinneret is a 0.1mm diameter × 30mm round hole, the spinneret speed is 1.2mL / min, the coagulation bath temperature is 55~60℃, the nascent fiber is washed with water, stretched 2.73 times in a 90℃ hot water bath, dried at 120~140℃, and then stretched 1.45 times on a hot plate at 300~340℃.
10. The method for preparing a flame-retardant high-elasticity fabric according to claim 5, characterized in that, The weaving and finishing process described in step (4) is as follows: elastic yarn is woven on a multi-functional flat knitting machine to make a plain weave fabric with a warp and weft density of 320×250 threads / 10cm and a thickness of 0.6±0.04mm. After singeing, boiling, drying and calendering, flame-retardant high elastic fabric is obtained.