Nylon flame retardant fiber and preparation process thereof

Abstract

The present invention relates to the field of flame-retardant fiber technology, and discloses a nylon flame-retardant fiber and a preparation process thereof. The nylon fiber prepared by the present invention comprises the following raw materials in parts by weight: 100 parts of nylon 6 chips, 3-5 parts of modified hydrotalcite, 2-6 parts of reinforcing filler, 0.3-0.6 parts of antioxidant, and 0.2-0.5 parts of lubricant. The modified hydrotalcite and reinforcing filler are added to improve not only the flame retardancy of the nylon fiber but also the antistatic performance and air permeability. The zinc doped in the modified hydrotalcite acts as an anti-melting droplet during combustion, and the interlayers of the hydrotalcite are intercalated and modified, further improving the flame retardancy of the matrix. The reinforcing filler is based on silicon dioxide and is surface-modified using a silane coupling agent, thereby improving the flame retardancy, antistatic performance, and air permeability of the matrix.

Description

Technical Field

[0001] The present invention relates to the technical field of flame-retardant fibers, and in particular to a nylon flame-retardant fiber and a preparation process thereof. Background Art

[0002] Nylon fiber possesses excellent physical and textile properties, including excellent resistance to wear, oil, low temperatures, and chemicals. It also boasts high strength, impact resistance, and ease of dyeing. Therefore, it is widely used in a variety of interior decorative fabrics, webbing, bedding, sofas, tents, and parachutes. However, due to its molecular structure, nylon fiber is flammable and prone to producing dripping during combustion, posing a significant safety hazard in everyday use. Furthermore, nylon fiber has drawbacks such as poor hygroscopicity, airtightness, and static charge generation.

[0003] To address the shortcomings of nylon fiber, its performance can be improved by modifying it. For example, hydrotalcite, which has flame retardant properties, can be added. However, to achieve the desired flame retardant effect, a large amount of hydrotalcite must be added. Therefore, the hydrotalcite needs to be treated, and a combination of organic and inorganic flame retardants can be used to achieve a small amount of flame retardant effect. Silica with a certain degree of air permeability can be added to improve the air permeability of the fiber, and the surface of the silica can be modified to improve the antistatic properties of the fiber. Therefore, through the above modifications, researchers can prepare a nylon fiber with excellent flame retardant, antistatic and breathable properties. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a nylon flame retardant fiber and a preparation process thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A nylon flame-retardant fiber comprises the following raw materials in parts by weight: 100 parts of nylon 6 chips, 3-5 parts of modified hydrotalcite, 2-6 parts of reinforcing filler, 0.3-0.6 parts of antioxidant, and 0.2-0.5 parts of lubricant;

[0007] The modified hydrotalcite is prepared by the following steps:

[0008] Step A1: Add methyl dichlorophosphate and acetonitrile to a flask and stir to mix evenly. Raise the system temperature to 60-70°C, add sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution three times with an interval of 10 minutes between each addition. Then, raise the temperature again to 80-90°C, reflux for 16-22 hours, and filter to obtain the N / P intercalant.

[0009] Step A2: Heat deionized water to a boiling state, add Zn(NO3)2·6H2O, Al(NO3)3·9H2O, and Mg(NO3)2·6H2O, and stir for 30 minutes. Then transfer the mixture to a beaker, maintain the system temperature at 70°C, adjust the system pH to 10.5-11.3, and continue stirring for 3-4 hours to obtain a hydrotalcite precursor. Then, add an N / P intercalant to the hydrotalcite precursor and continue stirring for 3-5 hours. After the reaction is completed, centrifuge, wash, and dry to obtain a modified hydrotalcite.

[0010] Furthermore, in step A1, the amount ratio of methyl dichlorophosphate, acetonitrile and sodium N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonate acetonitrile solution is 0.01-0.03 mol: 100 mL: 100 mL, and the sodium N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonate acetonitrile solution is prepared by mixing sodium N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonate and acetonitrile in an amount ratio of 0.02-0.06 mol: 100 mL;

[0011] Furthermore, in step A2, the usage ratio of deionized water, Zn(NO3)2·6H2O, Al(NO3)3·9H2O, Mg(NO3)2·6H2O and N / P intercalant is 100 mL: 0.03-0.06 mol: 0.03-0.04 mol: 0.03-0.06 mol: 0.03-0.06 mol.

[0012] The reinforcing filler is prepared by the following steps:

[0013] Step B1: Add bis(2-(2-methoxyethoxy)ethyl)amine to a flask containing methanol and stir to mix evenly under nitrogen. Then, add 1-pentene dropwise while stirring. After the addition is complete, raise the temperature to 35°C and react for 4-5 hours. After the reaction is complete, rotary evaporation is performed to obtain intermediate 1.

[0014] Step B2, epichlorohydrin was added to methanol and mixed and stirred evenly, and the mixture was heated to 60-70°C in an oil bath, and the intermediate product 1 was slowly added under stirring, and stirring was continued for 4-6 hours. After the reaction was completed, the mixture was cooled to room temperature, and distilled under reduced pressure and washed to obtain the intermediate product 2;

[0015] Step B3, add the intermediate product 2 to a flask containing methanol and stir to mix evenly, raise the temperature to 45-55°C, slowly add γ-aminopropyltriethoxysilane, and stir to react under nitrogen for 8-12 hours. After the reaction is completed, distill under reduced pressure, wash, and dry to obtain a product containing an ether bond function;

[0016] Step B4: Disperse nano-silica in a mixture of ethanol and deionized water, ultrasonically disperse for 30 minutes, then add the functional product, and heat to 60-70° C. for 4-6 hours. After the reaction is complete, the reinforced filler is obtained;

[0017] Furthermore, in step B1, the ratio of bis(2-(2-methoxyethoxy)ethyl)amine, methanol, and 1-pentene is 0.01-0.03 mol:100 mL:0.01-0.03 mol;

[0018] Furthermore, in step B2, the ratio of epichlorohydrin, methanol and intermediate 1 is 0.1-0.2 mol: 200 mL: 0.1-0.2 mol;

[0019] Furthermore, in step B3, the ratio of the intermediate product 2, methanol and γ-aminopropyltriethoxysilane is 0.1-0.2 mol: 100 mL: 0.1-0.2 mol;

[0020] Furthermore, in step B4, the usage ratio of nano-silica, ethanol, deionized water and the product containing ether bond functionality is 1 g:80 mL:20 mL:0.5-1 g.

[0021] A preparation process of nylon flame retardant fiber comprises the following steps:

[0022] Weigh the raw materials according to weight, add nylon 6 chips, modified hydrotalcite, reinforcing filler, antioxidant and lubricant into a high-speed mixer in sequence, mix and stir at a speed of 600-800 rpm for 10-15 minutes, then extrude into pellets through a twin-screw extruder, and then melt-spin the pellets through an FDY high-speed spinning machine to obtain nylon flame-retardant fiber;

[0023] Furthermore, the melt spinning process temperature is 220-230°C in zone 1, 230-240°C in zone 2, 230-245°C in zone 3, and 235-245°C in zone 4; the spinning speed is 4000-7000 m / min; and the draft ratio is 3-5 times.

[0024] Beneficial effects of the present invention:

[0025] The nylon fiber prepared by the present invention improves not only the flame retardancy of the nylon fiber but also the antistatic property and air permeability by adding modified hydrotalcite and reinforcing filler. The zinc doped in the modified hydrotalcite plays an anti-melting dripping role during combustion, and the interlayers of the hydrotalcite are intercalated and modified, thereby further improving the flame retardancy of the matrix. The reinforcing filler is based on silicon dioxide and is modified on its surface by using a silane coupling agent, thereby improving the flame retardancy, antistatic property and air permeability of the matrix.

[0026] In the modified hydrotalcite, the chlorine atoms in methyl dichlorophosphate are first reacted with the hydroxyl groups in sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate to obtain an N / P intercalant; then, Zn(NO3)2·6H2O, Al(NO3)3·9H2O and Mg(NO3)2·6H2O are used as zinc source, aluminum source and magnesium source, respectively, to prepare a hydrotalcite precursor, and then the negatively charged sulfonate ions in the N / P intercalant are used for intercalation modification through adsorption and exchange to obtain the modified hydrotalcite. The addition of modified hydrotalcite improves the flame retardancy of the matrix. This is because when the hydrotalcite decomposes under heat, it releases a large amount of water and carbon dioxide, which can dilute and block the combustible gas. At the same time, the magnesium and aluminum oxides produced by thermal decomposition and the carbonized products produced when the polymer burns can form a protective layer on the surface of the matrix, further blocking the intrusion of oxygen and achieving the gas-phase-solid-phase flame retardant effect. The zinc element forms zinc compounds when the matrix burns. The zinc compounds can form complexes with the amino groups produced when the polymer molecules decompose under heat, promoting the cross-linking of the decomposed matrix into carbon, causing the matrix to condense around the zinc compounds, thus avoiding the polymer transfer caused by combustion. The introduction of N / P intercalant further improves the flame retardant properties of hydrotalcite. This is because the phosphate and N source are introduced into the intercalant. When burning, the phosphate decomposes into phosphorus-containing free radicals such as P·, PO· and PO2· and acts as a free radical scavenger to capture active free radicals H· and OH· in the gas phase, thereby quenching free radicals, diluting the concentration of combustibles in the gas phase, interrupting the free radical chain reaction of combustion, and generating oxygen-containing phosphoric acid to promote the formation of a dense carbon layer in the matrix, thereby improving the flame retardant properties of the matrix. In addition, the NH3, N2 and NO generated by the thermal decomposition of the N source x Inert gases such as argon and argon can dilute the concentration of combustible and combustion-supporting gases in the air and cover the surface of the substrate to isolate it from the air.

[0027] In the reinforcing filler, a tertiary amine structure is first introduced by reacting the secondary amine in bis(2-(2-methoxyethoxy)ethyl)amine with the double bond in 1-pentene to obtain an intermediate product 1 containing an ether bond; then, the chlorine atom in epichlorohydrin reacts with the tertiary amine in the intermediate product 1 to generate an intermediate product 2 containing an epoxy group and a quaternary ammonium salt structure; then, the epoxy group in the intermediate product 2 reacts with the amino group in the silane coupling agent to generate a functional product containing an ether bond; finally, the silanol bond generated by the hydrolysis of the functional product containing an ether bond is condensed with the hydroxyl group on the surface of silica to obtain the reinforcing filler. The addition of reinforcing fillers further improves the comprehensive performance of the fiber; among them, silica is added to the fiber as the base of the reinforcing filler, which can widen the spacing between the fibers, thereby improving the air permeability of the fiber products. At the same time, silica also has a certain flame retardancy when the matrix burns; the introduction of hydrophilic ether bonds can enhance the hygroscopic properties of the matrix, easily attracting water molecules in the air, thereby improving the matrix's ability to adsorb water molecules in the surrounding environment, forming a layer of water film on the surface of the matrix, accelerating the dissipation rate of surface electrostatic charge, and improving the antistatic performance of the matrix. DETAILED DESCRIPTION

[0028] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention. Example 1

[0029] The modified hydrotalcite is prepared by the following steps:

[0030] Step A1: 0.01 mol of methyl dichlorophosphate and 100 mL of acetonitrile were added to a flask and stirred to mix evenly. The system temperature was raised to 60° C., and 100 mL of sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution was added three times with an interval of 10 minutes between each addition. The temperature was then raised to 80° C. again, and the mixture was refluxed for 16 hours. The mixture was then filtered to obtain an N / P intercalant. The sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution was prepared by mixing sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate and acetonitrile in a ratio of 0.02 mol:100 mL.

[0031] Step A2: Heat 100 mL of deionized water to a boiling state, add 0.03 mol of Zn(NO3)2·6H2O, 0.03 mol of Al(NO3)3·9H2O, and 0.03 mol of Mg(NO3)2·6H2O, and stir for 30 minutes. Then transfer the mixed solution to a beaker, maintain the system temperature at 70°C, adjust the system pH to 10.5, and continue stirring for 3 hours to obtain a hydrotalcite precursor. Then, add 0.03 mol of N / P intercalant to the hydrotalcite precursor and continue stirring for 3 hours. After the reaction is completed, centrifuge, wash, and dry to obtain the modified hydrotalcite.

[0032] The reinforcing filler is prepared by the following steps:

[0033] Step B1: Add 0.01 mol of bis(2-(2-methoxyethoxy)ethyl)amine to a flask containing 100 mL of methanol and stir to mix evenly under nitrogen. Then, add 0.01 mol of 1-pentene dropwise while stirring. After the addition is complete, raise the temperature to 35°C and react for 4 hours. After the reaction is complete, rotary evaporation is performed to obtain intermediate 1.

[0034] Step B2, 0.1 mol of epichlorohydrin was added to 200 mL of methanol and mixed and stirred evenly. The mixture was heated to 60° C. in an oil bath, and 0.1 mol of intermediate 1 was slowly added under stirring. The mixture was stirred for 4 h. After the reaction was completed, the mixture was cooled to room temperature, distilled under reduced pressure, and washed to obtain intermediate 2.

[0035] Step B3, 0.1 mol of intermediate product 2 was added to a flask containing 100 mL of methanol and stirred to mix evenly. The temperature was raised to 45° C., and 0.1 mol of γ-aminopropyltriethoxysilane was slowly added. The mixture was stirred and reacted under nitrogen for 8 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed, and dried to obtain a product containing an ether bond function;

[0036] Step B4: Disperse 1 g of nano-silica in a mixture of 80 mL of ethanol and 20 mL of deionized water, perform ultrasonic dispersion for 30 min, add 0.5 g of a product containing an ether bond function, and heat to 60° C. to react for 4 h. After the reaction is completed, a reinforced filler is obtained. Example 2

[0037] The modified hydrotalcite is prepared by the following steps:

[0038] Step A1: 0.02 mol of methyl dichlorophosphate and 100 mL of acetonitrile were added to a flask and stirred to mix evenly. The system temperature was raised to 65° C., and 100 mL of sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution was added three times with an interval of 10 minutes between each addition. The temperature was then raised to 85° C. again, and the mixture was refluxed for 19 hours. The mixture was then filtered to obtain an N / P intercalant. The sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution was prepared by mixing sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate and acetonitrile in a ratio of 0.04 mol:100 mL.

[0039] Step A2: Heat 100 mL of deionized water to a boiling state, add 0.045 mol of Zn(NO3)2·6H2O, 0.035 mol of Al(NO3)3·9H2O and 0.045 mol of Mg(NO3)2·6H2O and stir for 30 minutes, then transfer the mixed solution to a beaker, maintain the system temperature at 70°C, adjust the system pH to 11, and continue stirring for 3.5 hours to obtain a hydrotalcite precursor. Then, add 0.045 mol of N / P intercalant to the hydrotalcite precursor and continue stirring for 4 hours. After the reaction is completed, centrifuge, wash, and dry to obtain the modified hydrotalcite.

[0040] The reinforcing filler is prepared by the following steps:

[0041] Step B1: Add 0.02 mol of bis(2-(2-methoxyethoxy)ethyl)amine to a flask containing 100 mL of methanol and stir to mix evenly under nitrogen. Then, add 0.02 mol of 1-pentene dropwise while stirring. After the addition is complete, raise the temperature to 35°C and react for 4.5 hours. After the reaction is complete, rotary evaporation is performed to obtain intermediate 1.

[0042] Step B2, 0.15 mol of epichlorohydrin was added to 200 mL of methanol and mixed and stirred evenly. The mixture was heated to 65° C. in an oil bath, and 0.15 mol of intermediate 1 was slowly added under stirring. The mixture was stirred for 5 h. After the reaction was completed, the mixture was cooled to room temperature, distilled under reduced pressure, and washed to obtain intermediate 2.

[0043] Step B3, 0.15 mol of intermediate product 2 was added to a flask containing 100 mL of methanol and stirred to mix evenly. The temperature was raised to 50° C., and 0.15 mol of γ-aminopropyltriethoxysilane was slowly added. The mixture was stirred and reacted under nitrogen for 10 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed, and dried to obtain a product containing an ether bond function;

[0044] Step B4: Disperse 1 g of nano-silica in a mixture of 80 mL of ethanol and 20 mL of deionized water, perform ultrasonic dispersion for 30 min, add 0.75 g of a product containing an ether bond function, and heat to 65° C. to react for 5 h. After the reaction is completed, a reinforced filler is obtained. Example 3

[0045] The modified hydrotalcite is prepared by the following steps:

[0046] Step A1: 0.03 mol of methyl dichlorophosphate and 100 mL of acetonitrile were added to a flask and stirred to mix evenly. The system temperature was raised to 70° C., and 100 mL of sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution was added three times with an interval of 10 minutes between each addition. The temperature was then raised to 90° C. again, and the mixture was refluxed for 22 hours. The mixture was then filtered to obtain an N / P intercalant. The sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution was prepared by mixing sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate and acetonitrile in a ratio of 0.06 mol:100 mL.

[0047] Step A2: Heat 100 mL of deionized water to a boiling state, add 0.06 mol Zn(NO3)2·6H2O, 0.04 mol Al(NO3)3·9H2O and 0.06 mol Mg(NO3)2·6H2O and stir for 30 minutes, then transfer the mixed solution to a beaker, maintain the system temperature at 70°C, adjust the system pH to 11.3, and continue stirring for 4 hours to obtain a hydrotalcite precursor. Then, add 0.06 mol N / P intercalant to the hydrotalcite precursor and continue stirring for 5 hours. After the reaction is completed, centrifuge, wash, and dry to obtain the modified hydrotalcite.

[0048] The reinforcing filler is prepared by the following steps:

[0049] Step B1: Add 0.03 mol of bis(2-(2-methoxyethoxy)ethyl)amine to a flask containing 100 mL of methanol and stir to mix evenly under nitrogen. Then, add 0.03 mol of 1-pentene dropwise while stirring. After the addition is complete, raise the temperature to 35°C and react for 5 hours. After the reaction is complete, rotary evaporation is performed to obtain intermediate 1.

[0050] Step B2, 0.2 mol of epichlorohydrin was added to 200 mL of methanol and mixed and stirred evenly. The mixture was heated to 70° C. in an oil bath, and 0.2 mol of intermediate 1 was slowly added under stirring. The mixture was stirred for 6 h. After the reaction was completed, the mixture was cooled to room temperature, distilled under reduced pressure, and washed to obtain intermediate 2.

[0051] Step B3, 0.2 mol of intermediate product 2 was added to a flask containing 100 mL of methanol and stirred to mix evenly. The temperature was raised to 55° C., and 0.2 mol of γ-aminopropyltriethoxysilane was slowly added. The mixture was stirred under nitrogen for 12 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed, and dried to obtain a product containing an ether bond function;

[0052] Step B4: Disperse 1 g of nano-silica in a mixture of 80 mL of ethanol and 20 mL of deionized water, perform ultrasonic dispersion for 30 min, add 1 g of a product containing an ether bond function, and heat to 70° C. to react for 6 h. After the reaction is completed, a reinforced filler is obtained. Example 4

[0053] A preparation process of nylon flame retardant fiber comprises the following steps:

[0054] 100 parts of nylon 6 chips, 3 parts of modified hydrotalcite prepared in Example 1, 2 parts of reinforcing filler prepared in Example 1, 0.3 parts of diester of thiodipropionate, and 0.2 parts of alkyl diphenyl ether oil;

[0055] The raw materials were weighed according to weight, and nylon 6 chips, modified hydrotalcite prepared in Example 1, reinforcing filler prepared in Example 1, diester thiodipropionate and alkyl diphenyl ether oil were added to a high-speed mixer in sequence and mixed and stirred at a speed of 600 rpm for 10 minutes. The mixture was then extruded into pellets through a twin-screw extruder, and the pellets were melt-spun through an FDY high-speed spinning machine to obtain nylon flame-retardant fiber. The melt spinning process temperature was 220°C in zone 1, 230°C in zone 2, 230°C in zone 3, and 235°C in zone 4; the spinning speed was 4000 m / min, and the draft ratio was 3 times. Example 5

[0056] A preparation process of nylon flame retardant fiber comprises the following steps:

[0057] 100 parts of nylon 6 chips, 4 parts of modified hydrotalcite prepared in Example 2, 4 parts of reinforcing filler prepared in Example 2, 0.5 parts of diester of thiodipropionate, and 0.3 parts of alkyl diphenyl ether oil;

[0058] The raw materials were weighed by weight, and nylon 6 chips, modified hydrotalcite prepared in Example 2, reinforcing filler prepared in Example 2, diester thiodipropionate and alkyl diphenyl ether oil were added to a high-speed mixer in sequence, mixed and stirred at a speed of 700 rpm for 12 minutes, and then extruded into granules through a twin-screw extruder. The granules were melt-spun through an FDY high-speed spinning machine to obtain nylon flame-retardant fiber. The melt spinning process temperature was 225°C in zone 1, 235°C in zone 2, 240°C in zone 3, and 240°C in zone 4. The spinning speed was 5000 m / min and the draft ratio was 4 times. Example 6

[0059] A preparation process of nylon flame retardant fiber comprises the following steps:

[0060] 100 parts of nylon 6 chips, 5 parts of modified hydrotalcite prepared in Example 3, 6 parts of reinforcing filler prepared in Example 3, 0.6 parts of diester of thiodipropionate, and 0.5 parts of alkyl diphenyl ether oil;

[0061] The raw materials were weighed by weight, and nylon 6 chips, modified hydrotalcite prepared in Example 3, reinforcing filler prepared in Example 3, diester thiodipropionate and alkyl diphenyl ether oil were added to a high-speed mixer in sequence, mixed and stirred at a speed of 800 rpm for 15 minutes, and then extruded into pellets through a twin-screw extruder. The pellets were then melt-spun through an FDY high-speed spinning machine to obtain nylon flame-retardant fiber. The melt spinning process temperature was 230°C in zone 1, 240°C in zone 2, 245°C in zone 3, and 245°C in zone 4. The spinning speed was 7000 m / min and the draft ratio was 5 times.

[0062] Comparative Example 1

[0063] This comparative example is a nylon fiber, which differs from Example 6 in that an equal amount of hydrotalcite is used to replace the modified hydrotalcite prepared in Example 3, and the rest are the same.

[0064] Comparative Example 2

[0065] This comparative example is a nylon fiber, which differs from Example 6 in that an equal amount of silicon dioxide is used to replace the reinforcing filler prepared in Example 3, and all other aspects are the same.

[0066] The performance tests were performed on the nylon fibers prepared in Examples 4-6 and Comparative Examples 1-2:

[0067] Flame retardant performance test: in accordance with GB / T5455-2014 Textiles combustion performance - Determination of vertical direction damage length, smoldering and afterflaming time;

[0068] Antistatic performance test: Under the conditions of temperature of 25°C and relative humidity of 60%, using a high resistance meter MCP-HT450, applying a voltage of 250V, the initial surface resistivity of each embodiment and comparative example was measured;

[0069] Air permeability: The test method is GBT5453-1997 Air permeability test of textiles;

[0070] The test results are shown in the following table:

[0071] Limiting oxygen index (%) Afterburning time (s) Droplet situation Surface resistivity (Ω) Air permeability (mm / s) Example 4 28.5 0 No droplets <![CDATA[9.6×10 7 ]]> 48.5 Example 5 29.7 0 No droplets <![CDATA[8.9×10 7 ]]> 54.8 Example 6 32.8 0 No droplets <![CDATA[7.6×10 7 ]]> 60.1 Comparative Example 1 23.5 5 There are molten droplets <![CDATA[2.5×10 8 ]]> 47.6 Comparative Example 2 27.6 2 No droplets <![CDATA[9.7×10 9 ]]> 36.4

[0072] As can be seen from the above table, the nylon fiber prepared by the present invention has excellent flame retardancy, antistatic properties and air permeability, and can be widely used in the manufacture of textiles such as clothing, bedding, curtains, etc.

[0073] The above content is merely an example and explanation of the concept of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in a similar manner. As long as they do not deviate from the scope defined by the concept of the invention, they should all fall within the scope of protection of the present invention.

Claims

1. A nylon flame retardant fiber, characterized in that: The method comprises the following raw materials in parts by weight: 100 parts of nylon 6 chips, 3-5 parts of modified hydrotalcite, 2-6 parts of reinforcing filler, 0.3-0.6 parts of antioxidant, and 0.2-0.5 parts of lubricant; The modified hydrotalcite is prepared by the following steps: Step A1, adding methyl dichlorophosphate and acetonitrile into a flask and stirring to mix evenly, raising the system temperature to 60-70°C, adding sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution three times, each time with an interval of 10 minutes, then raising the temperature again to 80-90°C, reflux for 16-22 hours, and filtering to obtain the N / P intercalant; Step A2: Heat deionized water to a boiling state, add Zn(NO3)2·6H2O, Al(NO3)3·9H2O, and Mg(NO3)2·6H2O, and stir for 30 minutes. Then transfer the mixture to a beaker, maintain the system temperature at 70°C, adjust the system pH to 10.5-11.3, and continue stirring for 3-4 hours to obtain a hydrotalcite precursor. Then, add an N / P intercalant to the hydrotalcite precursor and continue stirring for 3-5 hours. After the reaction is completed, centrifuge, wash, and dry to obtain a modified hydrotalcite. The reinforcing filler is prepared by the following steps: Step B1, bis(2-(2-methoxyethoxy)ethyl)amine was added to a flask containing methanol and stirred under nitrogen to mix evenly. Then, 1-pentene was added dropwise while stirring. After the addition was completed, the temperature was raised to 35° C. and the reaction was carried out for 4-5 hours. After the reaction was completed, the mixture was rotary evaporated to obtain intermediate product 1; Step B2, epichlorohydrin was added to methanol and mixed and stirred evenly, and the mixture was heated to 60-70°C in an oil bath, and the intermediate product 1 was slowly added under stirring, and stirring was continued for 4-6 hours. After the reaction was completed, the mixture was cooled to room temperature, and distilled under reduced pressure and washed to obtain the intermediate product 2; Step B3, add the intermediate product 2 to a flask containing methanol and stir to mix evenly, raise the temperature to 45-55°C, slowly add γ-aminopropyltriethoxysilane, and stir to react under nitrogen for 8-12 hours. After the reaction is completed, distill under reduced pressure, wash, and dry to obtain a product containing an ether bond function; Step B4: disperse nano-silica in a mixture of ethanol and deionized water, perform ultrasonic dispersion for 30 minutes, add the functional product, and heat to 60-70° C. to react for 4-6 hours. After the reaction is completed, the reinforced filler is obtained.

2. The nylon flame retardant fiber according to claim 1, characterized in that: In step A1, the amount ratio of methyl dichlorophosphate, acetonitrile and sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution is 0.01-0.03 mol:100 mL:100 mL, and the sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate acetonitrile solution is prepared by mixing sodium N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonate and acetonitrile in an amount ratio of 0.02-0.06 mol:100 mL.

3. The nylon flame retardant fiber according to claim 1, characterized in that: In step A2, the usage ratio of deionized water, Zn(NO3)2·6H2O, Al(NO3)3·9H2O, Mg(NO3)2·6H2O and N / P intercalant is 100 mL: 0.03-0.06 mol: 0.03-0.04 mol: 0.03-0.06 mol: 0.03-0.06 mol.

4. The nylon flame retardant fiber according to claim 1, characterized in that: In step B1, the usage ratio of bis(2-(2-methoxyethoxy)ethyl)amine, methanol and 1-pentene is 0.01-0.03 mol:100 mL:0.01-0.03 mol.

5. The nylon flame retardant fiber according to claim 1, characterized in that: In step B2, the usage ratio of epichlorohydrin, methanol and intermediate product 1 is 0.1-0.2 mol: 200 mL: 0.1-0.2 mol.

6. The nylon flame retardant fiber according to claim 1, characterized in that: In step B3, the usage ratio of the intermediate product 2, methanol and γ-aminopropyltriethoxysilane is 0.1-0.2 mol:100 mL:0.1-0.2 mol.

7. The nylon flame-retardant fiber according to claim 1, characterized in that: In step B4, the usage ratio of nano-silica, ethanol, deionized water and the product containing ether bond functionality is 1 g:80 mL:20 mL:0.5-1 g.

8. The process for preparing a nylon flame retardant fiber according to claim 1, characterized in that: The following steps are involved: The raw materials are weighed according to weight, and nylon 6 chips, modified hydrotalcite, reinforcing filler, antioxidant and lubricant are added into a high-speed mixer in sequence and mixed and stirred at a speed of 600-800 rpm for 10-15 minutes. Then, the mixture is extruded into pellets through a twin-screw extruder, and the pellets are melt-spun through an FDY high-speed spinning machine to obtain nylon flame-retardant fiber.

9. The process for preparing a nylon flame-retardant fiber according to claim 8, characterized in that: The melt spinning process temperature is 220-230°C in zone 1, 230-240°C in zone 2, 230-245°C in zone 3, and 235-245°C in zone 4. The spinning speed is 4000-7000m / min, and the draft ratio is 3-5 times.