Lightweight high-branch high-density fabric and preparation method thereof

Abstract

This invention relates to the field of textile fabric technology, specifically a lightweight, high-count, high-density fabric and its preparation method. The invention involves a copolymerization reaction of potassium propyl 3-methyl methacrylate, a double-bond-terminated flame retardant, modified triphosphazene, glycidyl methacrylate, and azobisisobutyronitrile to obtain an antistatic flame retardant. The antistatic flame retardant and amino-terminated hyperbranched polyamide are pre-melted and blended, and then nylon 6 is added. The mixture is then melt-spun, drawn, and cooled to obtain modified nylon fibers. These modified nylon fibers are used as the core yarn, and an outer blended yarn is added. The resulting fabric is produced through a compact Sirosfil spinning process, twisting, and plain weave. The finished fabric obtained by this invention possesses excellent flame retardancy, antistatic properties, and toughness, thus having broad application prospects in the field of textile fabric technology.

Description

Technical Field

[0001] This invention relates to the field of textile fabric technology, specifically to a lightweight, high-count, high-density fabric and its preparation method. Background Technology

[0002] High-count, high-density fabrics possess a delicate, smooth texture and excellent drape, elevating the sensory experience of textiles to a new artistic level and deeply integrating into the process of contemporary industrial upgrading and improved consumer quality. However, these fabrics, especially the increasingly popular synthetic fiber materials, while providing superior texture, also bring a series of practical challenges that urgently need to be addressed. First, static electricity is becoming increasingly prominent in daily life, manifesting as clothing sticking to the skin, attracting dust, causing discomfort, and even producing unpleasant electric shocks in dry environments, severely impacting the wearing experience and functionality. Second, safety issues cannot be ignored. Textiles are flammable materials, and once ignited, they can spread rapidly and produce large amounts of toxic fumes, often playing a major role as a "fire carrier" in fires in residences, public transportation, and various public places. Furthermore, to meet the durability requirements of daily wear, fabrics must possess sufficient toughness; fabrics lacking toughness are easily damaged and deformed during wear, directly leading to a shortened product lifespan and premature disposal, which contradicts the current concept of sustainable consumption.

[0003] To overcome the shortcomings of the prior art, the present invention provides a lightweight high-count, high-density fabric and its preparation method. Summary of the Invention

[0004] The purpose of this invention is to provide a lightweight, high-count, high-density fabric and its preparation method, so as to solve the problems raised in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for preparing a lightweight, high-count, high-density fabric includes the following steps:

[0007] Step 1: Potassium propyl 3-sulfonate methacrylate, double bond-terminated flame retardant, modified triphosphazene, glycidyl methacrylate, and azobisisobutyronitrile are mixed and copolymerized to obtain an antistatic flame retardant; the antistatic flame retardant and amino-terminated hyperbranched polyamide are pre-melted and blended, and then nylon 6 is added. After melt spinning, drawing, and cooling, modified nylon fiber is obtained.

[0008] Step 2: Blend wool and polyester to obtain an outer blended yarn; use modified nylon fiber as the core yarn, add the outer blended yarn, and obtain core-spun yarn through a compact Sirofil spinning process; twist and weave the core-spun yarn in sequence to obtain the finished fabric.

[0009] In a more optimized manner, the melt blending temperature is 160-180℃, the melt spinning temperature is 250-260℃, the proportion of wool in the outer blended yarn is 65-75%, the proportion of core yarn in the core-spun yarn is 20-25%, and the twist is set to 1200-1300 twists / m.

[0010] In a more optimized manner, in step one, the content of each component of the modified nylon fiber is as follows: by mass parts, 90-100 parts nylon 6, 15-20 parts antistatic flame retardant, and 3-5 parts amino-terminated hyperbranched polyamide.

[0011] A more optimized preparation process for antistatic flame retardant is as follows:

[0012] Step S1: Under nitrogen atmosphere, hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, and 2,6-di-tert-butyl-p-cresol were mixed and stirred evenly. Hydroxyethyl methacrylate was then added dropwise. After the addition was completed, the temperature was raised to 90-100℃ and the reaction was continued for 13-15 hours. After the reaction was completed, the mixture was cooled, filtered, distilled under reduced pressure, and purified to obtain modified cyclotriphosphazene.

[0013] Step S2: Potassium propyl 3-sulfonate methacrylate, double bond-terminated flame retardant, and modified triphosphazene were added to anhydrous ethanol, followed by the sequential addition of glycidyl methacrylate and azobisisobutyronitrile. After the addition was completed, the mixture was stirred at 70-75℃ for 4.5-5.5 h. After the reaction was completed, the mixture was rotary evaporated, purified, and dried to obtain the antistatic flame retardant.

[0014] In a more optimized manner, the molar ratio of hexachlorocyclotriphosphazene to hydroxyethyl methacrylate is 1:(6.1-6.2); the mass ratio of potassium propyl 3-sulfonate methacrylate, double bond-terminated flame retardant, modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile is (5.2-5.4):(7.3-7.5):6:3:0.3.

[0015] A more optimized preparation process for double-bond-terminated flame retardants is as follows:

[0016] Step S1: Under nitrogen atmosphere, m-phenylenediamine and anhydrous acetonitrile are mixed and stirred to dissolve. Triethylamine is then added, and the temperature is lowered to 0-2℃. Then, phenylphosphonic dichloride solution is added dropwise. After the addition is completed, the reaction continues for 2-3 hours. Then, the temperature is raised to 20-25℃ and the reaction continues for 12-14 hours. After the reaction is completed, the mixture is filtered, rotary evaporated, precipitated, washed, and dried to obtain phenylphosphonic diamine.

[0017] Step S2: Terephthalaldehyde and ethanol are mixed to obtain a terephthalaldehyde solution; phenylphosphonic diamine and ethanol are mixed to obtain a phenylphosphonic diamine solution; under nitrogen atmosphere, the terephthalaldehyde solution and the phenylphosphonic diamine solution are mixed and refluxed at 78-82℃ for 9-10 hours. After the reaction is completed, the mixture is filtered, rotary evaporated, recrystallized, and dried to obtain an amino-terminated flame retardant.

[0018] Step S3: Glycidyl methacrylate, amino-terminated flame retardant, p-toluenesulfonic acid and toluene are mixed and refluxed at 110-120℃ for 4.5-5.5h. After the reaction is completed, the mixture is cooled, neutralized, dried, rotary evaporated and purified to obtain the double bond-terminated flame retardant.

[0019] In a more optimized manner, phenylphosphonic dichloride and anhydrous acetonitrile are mixed to obtain a phenylphosphonic dichloride solution; the reaction molar ratio of m-phenylenediamine to phenylphosphonic dichloride is (2.4-2.6):1; the reaction molar ratio of phenylphosphonic diamine to terephthalaldehyde is (2.2-2.4):1; and the reaction molar ratio of glycidyl methacrylate to amino-terminated flame retardant is (2.1-2.2):1.

[0020] In a more optimized manner, diethylenetriamine and distilled water are mixed, stirred evenly, and then N,N'-methylenebisacrylamide is added. The mixture is reacted at 65-70℃ for 18-22 hours. After the reaction is completed, the mixture is dehydrated under vacuum and washed to obtain amino-terminated hyperbranched polyamide.

[0021] The optimal reaction molar ratio of diethylenetriamine to N,N'-methylenebisacrylamide is (1.15-1.20):1.

[0022] The beneficial effects of this invention are:

[0023] The invention is characterized by the addition of m-phenylenediamine and phenylphosphonic dichloride, which undergo a nucleophilic substitution reaction to obtain phenylphosphonic diamine with amino groups at both ends. Then, terephthalaldehyde and phenylphosphonic diamine are mixed and subjected to a Schiff base reaction to obtain an amino-terminated flame retardant with amino groups at both ends. Furthermore, glycidyl methacrylate and the amino-terminated flame retardant are mixed and subjected to a ring-opening reaction to introduce carbon-carbon double bonds, resulting in a double-bond-terminated flame retardant. This double-bond-terminated flame retardant contains a phosphorus-based flame-retardant phenylphosphonic group and a Schiff base flame-retardant structure, thus exhibiting good flame retardancy. Hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, 2,6-di-tert-butyl-p-cresol, and hydroxyethyl methacrylate are mixed and subjected to a nucleophilic substitution reaction to obtain a hexa-double-bond-functionalized cyclotriphosphazene monomer, i.e., modified cyclotriphosphazene. The modified cyclotriphosphazene decomposes upon heating to produce non-flammable gases such as nitrogen, diluting oxygen and flammable gases. Phosphazene decomposes to generate phosphorus-containing oxyacids, which catalyze polymerization into char, forming an expanded char layer that provides thermal and oxygen insulation. Therefore, this modified triphosphazene significantly improves flame retardant efficiency through a phosphorus-nitrogen synergistic flame retardant system.

[0024] The present invention is characterized by a copolymerization reaction of potassium propyl 3-sulfonate methacrylate, a double-bond-terminated flame retardant, a modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile to obtain an antistatic flame retardant. The side chains of potassium propyl 3-sulfonate methacrylate contain strongly hydrophilic ionic groups. These groups can rapidly dissipate static charge by forming ionic conductive channels in the material, reducing surface resistance and providing a long-lasting antistatic effect. Therefore, by copolymerizing potassium propyl 3-sulfonate methacrylate, which has good antistatic properties, with a double-bond-terminated flame retardant and a modified cyclotriphosphazene, which have good flame retardancy, an antistatic flame retardant can be obtained. Furthermore, since glycidyl methacrylate is also added to this copolymer structure, epoxy groups are introduced into this antistatic flame retardant.

[0025] The key feature of this invention is the addition of diethylenetriamine and N,N'-methylenebisacrylamide to obtain amino-terminated hyperbranched polyamides. The amino groups of diethylenetriamine undergo addition to olefins, forming hyperbranched polyamides through a stepwise reaction involving multiple functional groups. Due to the excess of diethylenetriamine, the final terminal groups are amino. The antistatic flame retardant and the amino-terminated hyperbranched polyamides are then pre-melted and blended. After adding nylon 6, the mixture is melt-spun to obtain modified nylon fibers. The antistatic flame retardant has epoxy groups at the molecular chain ends or side chains, and the surface of the amino-terminated hyperbranched polyamide is densely covered with amino groups. Under the high temperature of melt blending, a ring-opening reaction can occur, forming strong covalent bonds. The addition of nylon 6 allows the exposed amino groups of the amino-terminated hyperbranched polyamides to react with the terminal carboxyl groups of nylon 6, thereby forming a chemically bonded flexible interface layer between the antistatic flame retardant and the nylon 6 matrix. This interface effectively transfers stress, prevents interface debonding, transforms brittle fracture into ductile fracture, and enhances the toughness of the material.

[0026] Modified nylon fiber is then used as the core yarn, and an outer layer of blended yarn is added. The resulting fabric is then produced through a compact Sirofil spinning process, twisting, and plain weave. The finished fabric obtained by this invention possesses excellent flame retardancy, antistatic properties, and toughness, thus having broad application prospects in the field of textile fabric technology. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Raw material source:

[0029] Nylon 6, supplied by Shanghai Bangsu New Materials Co., Ltd., grade HTN51G35HSL; outer blended yarn, supplied by Zhangjiagang Xianghe Textile Co., Ltd., with wool accounting for 70% and polyester accounting for 30%; by weight, one part is 1g.

[0030] Example 1: Step S1: Under nitrogen atmosphere, m-phenylenediamine and anhydrous acetonitrile were mixed and stirred until dissolved. Triethylamine was then added, and the temperature was lowered to 2°C. Then, phenylphosphonic dichloride solution was added dropwise. After the addition was completed, the reaction was continued for 3 hours, and then the temperature was raised to 25°C and the reaction was continued for 14 hours. After the reaction was completed, the mixture was filtered, rotary evaporated, precipitated, washed, and dried to obtain phenylphosphonic diamine. Phenylphosphonic dichloride and anhydrous acetonitrile were mixed to obtain phenylphosphonic dichloride solution. The molar ratio of m-phenylenediamine to phenylphosphonic dichloride was 2.5:1.

[0031] Step S2: Terephthalaldehyde and ethanol are mixed to obtain a terephthalaldehyde solution; phenylphosphonic diamine and ethanol are mixed to obtain a phenylphosphonic diamine solution; under nitrogen atmosphere, the terephthalaldehyde solution and the phenylphosphonic diamine solution are mixed and refluxed at 82℃ for 10 h. After the reaction is completed, the mixture is filtered, rotary evaporated, recrystallized, and dried to obtain an amino-terminated flame retardant; the molar ratio of phenylphosphonic diamine to terephthalaldehyde is 2.3:1.

[0032] Step S3: Glycidyl methacrylate, amino-terminated flame retardant, p-toluenesulfonic acid and toluene are mixed and refluxed at 120℃ for 5.5h. After the reaction is completed, the mixture is cooled, neutralized, dried, rotary evaporated and purified to obtain double bond-terminated flame retardant. The molar ratio of glycidyl methacrylate to amino-terminated flame retardant is 2.15:1.

[0033] Step S4: Under nitrogen atmosphere, hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, and 2,6-di-tert-butyl-p-cresol were mixed and stirred until homogeneous. Hydroxyethyl methacrylate was then added dropwise. After the addition was complete, the temperature was raised to 100°C and the reaction was continued for 15 hours. After the reaction was completed, the mixture was cooled, filtered, distilled under reduced pressure, and purified to obtain modified cyclotriphosphazene. The molar ratio of hexachlorocyclotriphosphazene to hydroxyethyl methacrylate was 1:6.15.

[0034] Step S5: Potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, and modified cyclotriphosphazene were added to anhydrous ethanol, followed by dropwise addition of glycidyl methacrylate and azobisisobutyronitrile. After the addition was complete, the mixture was stirred at 75°C for 5.5 h. After the reaction was completed, the mixture was rotary evaporated, purified, and dried to obtain the antistatic flame retardant. The mass ratio of potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile was 5.3:7.4:6:3:0.3.

[0035] Step S6: Mix diethylenetriamine and distilled water, stir well, and then add N,N'-methylenebisacrylamide. React at 70°C for 22 hours. After the reaction is complete, dehydrate and wash under vacuum to obtain amino-terminated hyperbranched polyamide. The molar ratio of diethylenetriamine to N,N'-methylenebisacrylamide is 1.17:1.

[0036] Step S7: 17g of antistatic flame retardant and 4g of amino-terminated hyperbranched polyamide are pre-melted and blended, and then 95g of nylon 6 is added. After melt spinning, stretching and cooling, modified nylon fiber is obtained. The melt blending temperature is 180℃ and the melt spinning temperature is 260℃.

[0037] Step S8: Blend wool and polyester to obtain an outer blended yarn; use modified nylon fiber as the core yarn, add the outer blended yarn, and obtain a core-spun yarn through a compact Sirofil spinning process; twist and weave the core-spun yarn sequentially to obtain the finished fabric; the proportion of wool in the outer blended yarn is 70%; the proportion of core yarn in the core-spun yarn is 23%; the twist is set to 1300 twists / m.

[0038] Example 2: Step S1: Under nitrogen atmosphere, m-phenylenediamine and anhydrous acetonitrile were mixed and stirred until dissolved. Triethylamine was then added, and the temperature was lowered to 1°C. Then, phenylphosphonic dichloride solution was added dropwise. After the addition was completed, the reaction was continued for 2.5 hours. The temperature was then raised to 23°C and the reaction was continued for 13 hours. After the reaction was completed, the mixture was filtered, rotary evaporated, precipitated, washed, and dried to obtain phenylphosphonic diamine. Phenylphosphonic dichloride and anhydrous acetonitrile were mixed to obtain phenylphosphonic dichloride solution. The molar ratio of m-phenylenediamine to phenylphosphonic dichloride was 2.5:1.

[0039] Step S2: Terephthalaldehyde and ethanol are mixed to obtain a terephthalaldehyde solution; phenylphosphonic diamine and ethanol are mixed to obtain a phenylphosphonic diamine solution; under nitrogen atmosphere, the terephthalaldehyde solution and the phenylphosphonic diamine solution are mixed and refluxed at 80°C for 9.5 h. After the reaction is completed, the mixture is filtered, rotary evaporated, recrystallized, and dried to obtain an amino-terminated flame retardant; the molar ratio of phenylphosphonic diamine to terephthalaldehyde is 2.3:1.

[0040] Step S3: Glycidyl methacrylate, amino-terminated flame retardant, p-toluenesulfonic acid and toluene are mixed and refluxed at 115℃ for 5 hours. After the reaction is completed, the mixture is cooled, neutralized, dried, rotary evaporated and purified to obtain double bond-terminated flame retardant. The molar ratio of glycidyl methacrylate to amino-terminated flame retardant is 2.15:1.

[0041] Step S4: Under nitrogen atmosphere, hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, and 2,6-di-tert-butyl-p-cresol were mixed and stirred until homogeneous. Hydroxyethyl methacrylate was then added dropwise. After the addition was complete, the temperature was raised to 95°C and the reaction was continued for 14 hours. After the reaction was completed, the mixture was cooled, filtered, distilled under reduced pressure, and purified to obtain modified cyclotriphosphazene. The molar ratio of hexachlorocyclotriphosphazene to hydroxyethyl methacrylate was 1:6.15.

[0042] Step S5: Potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, and modified cyclotriphosphazene were added to anhydrous ethanol, followed by dropwise addition of glycidyl methacrylate and azobisisobutyronitrile. After the addition was complete, the mixture was stirred at 72°C for 5 hours. After the reaction was completed, the mixture was rotary evaporated, purified, and dried to obtain the antistatic flame retardant. The mass ratio of potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile was 5.3:7.4:6:3:0.3.

[0043] Step S6: Mix diethylenetriamine and distilled water, stir evenly, then add N,N'-methylenebisacrylamide, and react at 67℃ for 20h. After the reaction is completed, dehydrate and wash under vacuum to obtain amino-terminated hyperbranched polyamide; the molar ratio of diethylenetriamine to N,N'-methylenebisacrylamide is 1.17:1.

[0044] Step S7: 17g of antistatic flame retardant and 4g of amino-terminated hyperbranched polyamide are pre-melted and blended, and then 95g of nylon 6 is added. After melt spinning, stretching, and cooling and shaping, modified nylon fiber is obtained; the melt blending temperature is 170℃ and the melt spinning temperature is 255℃.

[0045] Step S8: Wool and polyester are blended to obtain an outer blended yarn; modified nylon fiber is used as the core yarn, and the outer blended yarn is added. The core-spun yarn is obtained through a compact Sirofil spinning process; the core-spun yarn is twisted and woven in a plain weave to obtain the finished fabric; the proportion of wool in the outer blended yarn is 70%; the proportion of core yarn in the core-spun yarn is 23%; the twist is set to 1250 twists / m.

[0046] Example 3: Step S1: Under nitrogen atmosphere, m-phenylenediamine and anhydrous acetonitrile were mixed and stirred until dissolved. Triethylamine was then added, and the temperature was lowered to 0°C. Then, phenylphosphonic dichloride solution was added dropwise. After the addition was completed, the reaction was continued for 2 hours, and then the temperature was raised to 20°C and the reaction was continued for 12 hours. After the reaction was completed, the mixture was filtered, rotary evaporated, precipitated, washed, and dried to obtain phenylphosphonic diamine. Phenylphosphonic dichloride and anhydrous acetonitrile were mixed to obtain phenylphosphonic dichloride solution. The molar ratio of m-phenylenediamine to phenylphosphonic dichloride was 2.5:1.

[0047] Step S2: Terephthalaldehyde and ethanol are mixed to obtain a terephthalaldehyde solution; phenylphosphonic diamine and ethanol are mixed to obtain a phenylphosphonic diamine solution; under nitrogen atmosphere, the terephthalaldehyde solution and the phenylphosphonic diamine solution are mixed and refluxed at 78°C for 9 hours. After the reaction is completed, the mixture is filtered, rotary evaporated, recrystallized, and dried to obtain an amino-terminated flame retardant; the molar ratio of phenylphosphonic diamine to terephthalaldehyde is 2.3:1.

[0048] Step S3: Glycidyl methacrylate, amino-terminated flame retardant, p-toluenesulfonic acid and toluene are mixed and refluxed at 110℃ for 4.5h. After the reaction is completed, the mixture is cooled, neutralized, dried, rotary evaporated and purified to obtain double bond-terminated flame retardant. The molar ratio of glycidyl methacrylate to amino-terminated flame retardant is 2.15:1.

[0049] Step S4: Under nitrogen atmosphere, hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, and 2,6-di-tert-butyl-p-cresol were mixed and stirred until homogeneous. Hydroxyethyl methacrylate was then added dropwise. After the addition was complete, the temperature was raised to 90°C and the reaction was continued for 13 hours. After the reaction was completed, the mixture was cooled, filtered, distilled under reduced pressure, and purified to obtain modified cyclotriphosphazene. The molar ratio of hexachlorocyclotriphosphazene to hydroxyethyl methacrylate was 1:6.15.

[0050] Step S5: Potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, and modified cyclotriphosphazene were added to anhydrous ethanol, followed by dropwise addition of glycidyl methacrylate and azobisisobutyronitrile. After the addition was complete, the mixture was stirred at 70°C for 4.5 h. After the reaction was completed, the mixture was rotary evaporated, purified, and dried to obtain the antistatic flame retardant. The mass ratio of potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile was 5.3:7.4:6:3:0.3.

[0051] Step S6: Mix diethylenetriamine and distilled water, stir well, and then add N,N'-methylenebisacrylamide. React at 65°C for 18 hours. After the reaction is complete, dehydrate and wash under vacuum to obtain amino-terminated hyperbranched polyamide. The molar ratio of diethylenetriamine to N,N'-methylenebisacrylamide is 1.17:1.

[0052] Step S7: 17g of antistatic flame retardant and 4g of amino-terminated hyperbranched polyamide are pre-melted and blended, and then 95g of nylon 6 is added. After melt spinning, stretching and cooling, modified nylon fiber is obtained. The melt blending temperature is 160℃ and the melt spinning temperature is 250℃.

[0053] Step S8: Blend wool and polyester to obtain an outer blended yarn; use modified nylon fiber as the core yarn, add the outer blended yarn, and obtain a core-spun yarn through a compact Sirofil spinning process; twist and weave the core-spun yarn sequentially to obtain the finished fabric; the proportion of wool in the outer blended yarn is 70%; the proportion of core yarn in the core-spun yarn is 23%; the twist is set to 1200 twists / m.

[0054] Comparative Example 1: The antistatic flame retardant was removed, and the rest was the same as in Example 1. The specific steps are as follows: Step S1: Diethylenetriamine and distilled water were mixed and stirred evenly, and then N,N'-methylenebisacrylamide was added. The mixture was reacted at 70°C for 22 hours. After the reaction was completed, the mixture was dehydrated under vacuum and washed to obtain amino-terminated hyperbranched polyamide. The molar ratio of diethylenetriamine to N,N'-methylenebisacrylamide was 1.17:1.

[0055] Step S2: Mix 4g of amino-terminated hyperbranched polyamide and 95g of nylon 6, and then melt spin, draw, and cool to set to obtain modified nylon fiber; the melt spinning temperature is 260℃.

[0056] Step S3: Wool and polyester are blended to obtain an outer blended yarn; modified nylon fiber is used as the core yarn, and the outer blended yarn is added. The core-spun yarn is obtained through a compact Sirofil spinning process; the core-spun yarn is twisted and woven in a plain weave to obtain the finished fabric; the proportion of wool in the outer blended yarn is 70%; the proportion of core yarn in the core-spun yarn is 23%; the twist is set to 1300 twists / m.

[0057] Comparative Example 2: The terminal amino hyperbranched polyamide was removed, and the rest was the same as in Example 1. The specific steps are as follows: Step S1: Under nitrogen atmosphere, m-phenylenediamine and anhydrous acetonitrile were mixed and stirred to dissolve. Triethylamine was then added, and the temperature was lowered to 2°C. Then, phenylphosphonic dichloride solution was added dropwise. After the addition was completed, the reaction was continued for 3 hours. Then, the temperature was raised to 25°C and the reaction was continued for 14 hours. After the reaction was completed, the mixture was filtered, rotary evaporated, precipitated, washed, and dried to obtain phenylphosphonic diamine. Phenylphosphonic dichloride and anhydrous acetonitrile were mixed to obtain phenylphosphonic dichloride solution. The molar ratio of m-phenylenediamine to phenylphosphonic dichloride was 2.5:1.

[0058] Step S2: Terephthalaldehyde and ethanol are mixed to obtain a terephthalaldehyde solution; phenylphosphonic diamine and ethanol are mixed to obtain a phenylphosphonic diamine solution; under nitrogen atmosphere, the terephthalaldehyde solution and the phenylphosphonic diamine solution are mixed and refluxed at 82℃ for 10 h. After the reaction is completed, the mixture is filtered, rotary evaporated, recrystallized, and dried to obtain an amino-terminated flame retardant; the molar ratio of phenylphosphonic diamine to terephthalaldehyde is 2.3:1.

[0059] Step S3: Glycidyl methacrylate, amino-terminated flame retardant, p-toluenesulfonic acid and toluene are mixed and refluxed at 120℃ for 5.5h. After the reaction is completed, the mixture is cooled, neutralized, dried, rotary evaporated and purified to obtain double bond-terminated flame retardant. The molar ratio of glycidyl methacrylate to amino-terminated flame retardant is 2.15:1.

[0060] Step S4: Under nitrogen atmosphere, hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, and 2,6-di-tert-butyl-p-cresol were mixed and stirred until homogeneous. Hydroxyethyl methacrylate was then added dropwise. After the addition was complete, the temperature was raised to 100°C and the reaction was continued for 15 hours. After the reaction was completed, the mixture was cooled, filtered, distilled under reduced pressure, and purified to obtain modified cyclotriphosphazene. The molar ratio of hexachlorocyclotriphosphazene to hydroxyethyl methacrylate was 1:6.15.

[0061] Step S5: Potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, and modified cyclotriphosphazene were added to anhydrous ethanol, followed by dropwise addition of glycidyl methacrylate and azobisisobutyronitrile. After the addition was complete, the mixture was stirred at 75°C for 5.5 h. After the reaction was completed, the mixture was rotary evaporated, purified, and dried to obtain the antistatic flame retardant. The mass ratio of potassium propyl 3-sulfonate methacrylate, double-bond end-capped flame retardant, modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile was 5.3:7.4:6:3:0.3.

[0062] Step S6: Mix 17g of antistatic flame retardant and 95g of nylon 6, and then melt spin, draw, and cool to set to obtain modified nylon fiber; the melt spinning temperature is 260℃.

[0063] Step S7: Blend wool and polyester to obtain an outer blended yarn; use modified nylon fiber as the core yarn, add the outer blended yarn, and obtain a core-spun yarn through a compact Sirofil spinning process; twist and weave the core-spun yarn sequentially to obtain the finished fabric; the proportion of wool in the outer blended yarn is 70%; the proportion of core yarn in the core-spun yarn is 23%; the twist is set to 1300 twists / m.

[0064] Testing and experimentation:

[0065] Flame retardancy test: The finished fabric prepared by this invention is used as a sample. Referring to GB / T 5454-1997 "Test for Burning Performance of Textiles - Oxygen Index Method", under the specified test conditions, the minimum oxygen concentration required for the sample to just maintain a burning state in the oxygen-nitrogen mixture is tested, which is the oxygen index of the sample.

[0066] Antistatic property test: The finished fabric prepared by this invention is used as a sample. The antistatic property of the sample is evaluated with reference to GB / T 12703.1-2021 "Textiles - Test methods for electrostatic properties - Part 1: Corona charging method" (half-life HDT≤10s: excellent; 10s < half-life HDT≤30s: good; 30s < half-life HDT≤60s: fair).

[0067] Tear strength test: The finished fabric prepared according to this invention was used as the sample. Referring to GB / T 3917.1-2009 "Textiles - Tear Properties of Fabrics - Part 1: Determination of Tear Strength by Impact Pendulum Method", the sample was fixed on a fixture, a slit was cut in the sample, and the pendulum at its maximum potential energy position was released. When the movable fixture left the fixed fixture, the sample was torn along the slit direction. The force required to expand the initial slit on the sample was taken as the tear strength. The results are shown in the table below:

[0068]

[0069] Conclusion: In Examples 1-3, the dosage remained unchanged, with only some reaction parameters modified. Experimental data show that the various properties of the samples did not exhibit significant fluctuations.

[0070] Comparative Example 1: The antistatic flame retardant was removed, and the rest was the same as in Example 1. The experimental data showed that, compared with Example 1, the oxygen index decreased to 25.2%, and the antistatic performance was rated as average. The reason for this is that the antistatic flame retardant contains an NP synergistic flame retardant system, which has excellent flame retardant performance. Removing it will significantly reduce the flame retardant performance and decrease the oxygen index. The antistatic flame retardant also contains strongly hydrophilic ionic groups, which can provide a long-lasting antistatic effect. Therefore, removing them will worsen the antistatic performance.

[0071] Comparative Example 2: The terminal amino hyperbranched polyamide was removed, and the rest was the same as in Example 1. The experimental data showed that the tear strength was reduced to 31N compared with Example 1. The reason for this is that the terminal amino hyperbranched polyamide can react with the terminal carboxyl groups of nylon 6, thereby establishing a strong, chemically bonded flexible interface layer between the antistatic flame retardant and the nylon 6 matrix, which effectively toughens the material. Therefore, removing it reduces the toughness and tear strength.

[0072] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process method article or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process method article or apparatus.

[0073] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a lightweight, high-count, high-density fabric, characterized in that: Includes the following steps: Step 1: Potassium propyl 3-sulfonate methacrylate, double bond-terminated flame retardant, modified triphosphazene, glycidyl methacrylate, and azobisisobutyronitrile are mixed and copolymerized to obtain an antistatic flame retardant; the antistatic flame retardant and amino-terminated hyperbranched polyamide are pre-melted and blended, and then nylon 6 is added. After melt spinning, drawing, and cooling, modified nylon fiber is obtained. The content of each component in the modified nylon fiber is as follows (by mass): 90-100 parts nylon 6, 15-20 parts antistatic flame retardant, and 3-5 parts amino-terminated hyperbranched polyamide. The preparation process of the antistatic flame retardant is as follows: Step S1: Under nitrogen atmosphere, hexachlorocyclotriphosphazene, dioxane, N,N-dimethylaniline, and 2,6-di-tert-butyl-p-cresol were mixed and stirred evenly. Hydroxyethyl methacrylate was then added dropwise. After the addition was completed, the temperature was raised to 90-100℃ and the reaction was continued for 13-15 hours. After the reaction was completed, the mixture was cooled, filtered, distilled under reduced pressure, and purified to obtain modified cyclotriphosphazene. Step S2: Potassium propyl 3-sulfonate methacrylate, double bond-terminated flame retardant, and modified triphosphazene were added to anhydrous ethanol, followed by the sequential addition of glycidyl methacrylate and azobisisobutyronitrile. After the addition was completed, the mixture was stirred at 70-75℃ for 4.5-5.5 h. After the reaction was completed, the mixture was rotary evaporated, purified, and dried to obtain the antistatic flame retardant. The molar ratio of hexachlorocyclotriphosphazene to hydroxyethyl methacrylate is 1:(6.1-6.2); the mass ratio of potassium propyl 3-sulfonate methacrylate, double bond-terminated flame retardant, modified cyclotriphosphazene, glycidyl methacrylate, and azobisisobutyronitrile is (5.2-5.4):(7.3-7.5):6:3:0.

3. Step 2: Blend wool and polyester to obtain an outer blended yarn; use modified nylon fiber as the core yarn, add the outer blended yarn, and obtain core-spun yarn through a compact Sirofil spinning process; twist and weave the core-spun yarn in sequence to obtain the finished fabric.

2. The method for preparing a lightweight, high-count, high-density fabric according to claim 1, characterized in that: The melt blending temperature is 160-180℃, and the melt spinning temperature is 250-260℃; the proportion of wool in the outer blended yarn is 65-75%; the proportion of core yarn in the core-spun yarn is 20-25%; and the twist is set to 1200-1300 twists / m.

3. The method for preparing a lightweight, high-count, high-density fabric according to claim 1, characterized in that: The preparation process of double-bond-terminated flame retardants is as follows: Step S1: Under nitrogen atmosphere, m-phenylenediamine and anhydrous acetonitrile are mixed and stirred to dissolve. Triethylamine is then added, and the temperature is lowered to 0-2℃. Then, phenylphosphonic dichloride solution is added dropwise. After the addition is completed, the reaction continues for 2-3 hours. Then, the temperature is raised to 20-25℃ and the reaction continues for 12-14 hours. After the reaction is completed, the mixture is filtered, rotary evaporated, precipitated, washed, and dried to obtain phenylphosphonic diamine. Step S2: Terephthalaldehyde and ethanol are mixed to obtain a terephthalaldehyde solution; phenylphosphonic diamine and ethanol are mixed to obtain a phenylphosphonic diamine solution; under nitrogen atmosphere, the terephthalaldehyde solution and the phenylphosphonic diamine solution are mixed and refluxed at 78-82℃ for 9-10 hours. After the reaction is completed, the mixture is filtered, rotary evaporated, recrystallized, and dried to obtain an amino-terminated flame retardant. Step S3: Glycidyl methacrylate, amino-terminated flame retardant, p-toluenesulfonic acid and toluene are mixed and refluxed at 110-120℃ for 4.5-5.5h. After the reaction is completed, the mixture is cooled, neutralized, dried, rotary evaporated and purified to obtain the double bond-terminated flame retardant.

4. The method for preparing a lightweight, high-count, high-density fabric according to claim 3, characterized in that: Phenylphosphonic dichloride and anhydrous acetonitrile were mixed to obtain a phenylphosphonic dichloride solution; the reaction molar ratio of m-phenylenediamine to phenylphosphonic dichloride was (2.4-2.6):1; the reaction molar ratio of phenylphosphonic diamine to terephthalaldehyde was (2.2-2.4):1; and the reaction molar ratio of glycidyl methacrylate to amino-terminated flame retardant was (2.1-2.2):

1.

5. The method for preparing a lightweight, high-count, high-density fabric according to claim 1, characterized in that: Diethylenetriamine and distilled water were mixed and stirred evenly before N,N'-methylenebisacrylamide was added. The mixture was reacted at 65-70℃ for 18-22 hours. After the reaction was completed, the mixture was dehydrated under vacuum and washed to obtain amino-terminated hyperbranched polyamide.

6. The method for preparing a lightweight, high-count, high-density fabric according to claim 5, characterized in that: The molar ratio of diethylenetriamine to N,N'-methylenebisacrylamide is (1.15-1.20):

1.

7. A lightweight, high-count, high-density fabric, characterized in that, Prepared by the preparation method according to any one of claims 1-6.

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