High-strength polyamide 66 fiber material and preparation method thereof

Abstract

The invention relates to a high-strength polyamide 66 fiber material and a preparation method thereof, in particular to a method for improving the level dyeing performance of a fine-denier high-strength polyamide 66 fiber material by introducing a sulfonic acid group and a pyridine ring into a polyamide 66 molecular chain. The preparation method is characterized by comprising the following steps: firstly, carrying out salt forming reaction on a compound containing a sulfonic acid group and aliphatic diamine to obtain amide salt containing the sulfonic acid group, carrying out salt forming reaction on a compound containing a pyridine ring and aliphatic dibasic acid or diamine to obtain amide salt containing the pyridine ring, and then mixing the amide salt containing the pyridine ring and nylon 66 salt to obtain the nylon 66 composite material. Carrying out melt polycondensation to obtain polyamide 66 with a molecular chain containing sulfonic acid groups and pyridine rings, and then carrying out melt spinning to obtain the high-strength polyamide 66 fiber material. The prepared high-strength polyamide 66 fiber material is high in breaking strength, high in dye uptake and good in dyeing uniformity.

Description

Technical Field

[0001] The present invention belongs to the field of polyamide fiber preparation, and relates to a high-strength polyamide 66 fiber material and a preparation method, and in particular to a method for obtaining a fine-denier high-strength polyamide 66 fiber material by melt spinning after preparing modified polyamide 66 by introducing sulfonic acid groups and pyridine rings into polyamide 66 molecular chains. Background Art

[0002] Polyamide 66 fiber has the characteristics of high strength, wear resistance, cold resistance, aging resistance and comfort, and is widely used in the field of textiles and clothing. Among them, fine denier high-strength polyamide 66 fiber has good mechanical properties, softness, hygroscopicity and breathability, and can be used to make sportswear, military clothing, protective clothing and other end products with high performance requirements. With the increase of the degree of refinement, the diameter of the fine denier fiber monofilament becomes smaller and the specific surface area increases, which can give the fabric the characteristics of fluffiness, coverage, softness, thermal insulation, moisture permeability and waterproofness. However, due to the large specific surface area of ​​fine denier fiber and the fast dyeing rate of dye, its level dyeing property becomes worse, and uneven dyeing is prone to occur, which is a severe test for polyamide 66 fiber with relatively poor level dyeing. Therefore, in-depth research on the level dyeing performance of fine denier high-strength polyamide 66 fiber and exploration of effective ways to improve its level dyeing effect are of vital importance to broaden its application range, enhance product competitiveness and meet the diversified needs of the market.

[0003] Fine-denier polyamide 66 fibers have a small diameter and a relatively large specific surface area, so dyes are more easily adsorbed on the surface, and the dye concentration inside the fiber is relatively low, which leads to uneven dyeing problems such as color spots, yin and yang surfaces, and step differences in the fine-denier polyamide 66 fiber during the dyeing process. Chinese patent CN103132349A discloses a dyeing and finishing method for ultra-fine-denier polyamide fabrics, which reduces the initial dyeing speed of the dye by using an anionic leveling agent to achieve a leveling effect. However, the patent only improves the dyeing performance of fine-denier polyamide by adding a leveling agent, and fails to fundamentally solve the technical bottleneck of the difficulty in leveling fine-denier polyamide 66 fibers. Summary of the invention

[0004] The present invention provides a method for preparing a high-strength polyamide 66 fiber material, and more particularly relates to a method for obtaining a fine-denier high-strength polyamide 66 fiber material by melt spinning after preparing modified polyamide 66 by introducing sulfonic acid groups and pyridine rings into a polyamide 66 molecular chain.

[0005] The high-strength polyamide 66 fiber prepared by the present invention is copolymerized with sulfonic acid groups and pyridine ring structures to the main chain of the polyamide 66 molecule, and a small amount of sulfonic acid groups are combined with terminal amino groups, thereby increasing the resistance to acid dyes, appropriately slowing down the dyeing rate of acid dyes in the fiber, delaying the dyeing time, and facilitating the uniform diffusion and combination of dyes on the fiber surface and inside. The pyridine ring structure contains basic nitrogen atoms, which increases the number of "dyeing sites" in the molecular chain when polyamide 66 is dyed, improves the dyeing rate of polyamide 66 fiber, and to a certain extent makes up for the defect of reduced dyeing rate caused by reduced number of terminal amino groups.

[0006] The present invention provides a high-strength polyamide 66 fiber material having the following structure:

[0007] Where m is 4~10, n is 4~10, x is 1~35, y is 32~146, z is 1~35, and the structure of R' is as follows:

[0008] The structure of R is as follows:

[0009] The present invention also provides a method for preparing a high-strength polyamide 66 fiber material, the specific steps of which are as follows: (1) adding a dibasic acid containing a sulfonic acid group and an aliphatic diamine to water or ethanol in a certain ratio, and performing a salt-forming reaction at room temperature. After the salt is precipitated, filtering, washing, and drying are performed to obtain an amide salt containing a sulfonic acid group; (2) adding a pyridine ring structure compound and an aliphatic dibasic acid or diamine to water or ethanol in a certain proportion, stirring at 60-90°C for 1-12 hours, filtering, washing and drying after the salt is precipitated to obtain an amide salt containing a pyridine ring structure; (3) Add 1-50 parts of salt containing sulfonic acid groups, 1-50 parts of amide salt containing pyridine ring structure, 75-100 parts of nylon 66 salt, and 60-80 parts of deionized water into a polymerization reaction kettle, and replace the air in the kettle with nitrogen for 3 times; turn on the heating, slowly raise the temperature to 215-235°C, and maintain the pressure at 1.8-2.0 MPa for condensation for 2-3 hours; continue to raise the temperature to 245-255°C, and reduce the pressure to normal pressure 0 MPa after 0.5-1 hour; continue to raise the temperature to 270-280°C, evacuate to a pressure of -0.01-0.10 MPa, and maintain the temperature and pressure for 1-3 hours to obtain polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain; (4) Polyamide 66 containing sulfonic acid groups and pyridine ring structures or polyamide 66 containing sulfonic acid groups and pyridine ring structures and conventional polyamide 66 are mixed in a certain proportion and then spun in a melt spinning machine to obtain a high-strength polyamide 66 fiber material.

[0010] In the method for preparing a high-strength polyamide 66 fiber material as described above, in step (1), the sulfonic acid group-containing compound is sodium 5-sulfonate of isophthalic acid; and the aliphatic diamine is a straight-chain aliphatic diamine having 4 to 10 carbon atoms.

[0011] In the method for preparing a high-strength polyamide 66 fiber material as described above, in step (1), the dibasic acid containing a sulfonic acid group and the aliphatic diamine are subjected to a salt-forming reaction in a molar ratio of 1:1.02-1.05.

[0012] In the method for preparing a high-strength polyamide 66 fiber material as described above, in step (2), the pyridine ring structure compound includes a pyridine ring-containing dibasic acid and a pyridine ring-containing diamine, the pyridine ring-containing dibasic acid includes one or more of 2,6-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2,3-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, and 3,4-pyridinedicarboxylic acid, and the pyridine ring-containing diamine includes one or more of 2,6-diaminopyridine, 2,5-diaminopyridine, 2,4-diaminopyridine, 2,3-diaminopyridine, 3,5-diaminopyridine, and 3,4-diaminopyridine; the aliphatic dibasic acid is a straight-chain aliphatic dibasic acid having 4 to 12 carbon atoms; and the aliphatic diamine is a straight-chain aliphatic diamine having 4 to 10 carbon atoms.

[0013] In the method for preparing a high-strength polyamide 66 fiber material as described above, in step (2), when the pyridine ring structure-containing compound is a diamine structure, the pyridine ring-containing diamine and the aliphatic dibasic acid are subjected to a salt-forming reaction at a molar ratio of 1.02 to 1.05:1; when the pyridine ring structure-containing compound is a dibasic acid structure, the pyridine ring-containing dibasic acid and the aliphatic diamine are subjected to a salt-forming reaction at a molar ratio of 1:1.02 to 1.05.

[0014] In the method for preparing a high-strength polyamide 66 fiber material as described above, in step (3), the number average molecular weight of the polyamide 66 whose molecular chain contains sulfonic acid groups and pyridine ring structures is 17000-24000 g / mol.

[0015] In the method for preparing a high-strength polyamide 66 fiber material as described above, in step (4), when x is 1-4, y is 70-146, and z is 1-4, the polyamide 66 with a sulfonic acid group and a pyridine ring structure in the molecular chain can be spun alone, and when x is 4-35, y is 32-70, and z is 4-35, the polyamide 66 with a sulfonic acid group and a pyridine ring structure in the molecular chain is mixed with conventional polyamide 66 in a ratio of 1:36-196 and then spun.

[0016] In the method for preparing a high-strength polyamide 66 fiber material as described above, the melt spinning conditions in step (4) are a temperature of 280-295° C., a winding speed of 2500-3500 m / min, and a stretching multiple of 4.5-5.5.

[0017] The method for preparing a high-strength polyamide 66 fiber material as described above has a single-filament fineness of 0.9-1.4 dtex, a breaking strength of 6.5-8.2 cN / dtex, and a breaking elongation of 16.4-24.7%. After the fiber is knitted into a slender stocking tube by a hosiery machine, the coloring rate is measured using acid red N-2RB or LNAVY MPA acid dye according to "GB / T23976.1-2009 Dyeing rate curve determination method for coloring rate determination", and is evaluated according to "GB / T 21881-2015 Determination of level dyeing of acid dyes". The tube socks knitted by the present invention have a level dyeing property of grade 5, a coloring rate of 98.1-99.2%, and a K / S value of 24.5-28.5.

[0018] The technical solution of the present invention can achieve the following beneficial effects: (1) Significantly improve the leveling performance of fine-denier high-strength polyamide 66 fiber: By introducing sulfonic acid groups into the main chain of polyamide 66 fiber molecules, the dyeing rate of acid dyes is effectively reduced and the dyeing time is delayed. This design significantly improves the leveling effect of fine-denier high-strength polyamide 66 fiber, overcoming the problem of uneven dyeing caused by the excessively fast dyeing rate of traditional fine-denier polyamide 66 fiber. At the same time, by introducing pyridine rings into the main chain of polyamide 66 fiber molecules, the number of "dyeing sites" in the molecular chain of polyamide 66 is increased during dyeing, which to a certain extent compensates for the defect of reduced dyeing rate caused by the reduction in the number of terminal amino groups. The sulfonic acid group and the pyridine ring work together to improve the leveling performance of fine-denier high-strength polyamide 66 fiber.

[0019] (2) Expanding the application scope of fine-denier high-strength polyamide 66 fiber: Due to the improvement of uniform dyeing performance, fine-denier high-strength polyamide 66 fiber can present richer colors and higher aesthetics, thereby meeting the demand for color diversity in more fields. This helps to expand the application scope of fine-denier high-strength polyamide 66 fiber, especially in the fields of textiles, clothing, home decoration, etc. that require high color expression. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0021] Example 1 The method of the present invention is used to produce high-strength polyamide 66 fiber material, and the specific steps are as follows: (1) adding sodium 5-sulfoisophthalic acid and 1,6-hexanediamine in a molar ratio of 1:1.02 to water, reacting at room temperature, filtering, washing and drying after salt precipitation to obtain an amide salt containing a sulfonic acid group; (2) adding 2,4-pyridinedicarboxylic acid and 1,6-hexanediamine in a molar ratio of 1:1.02 into water, stirring at 60°C for 1 hour, filtering, washing and drying after salt precipitation to obtain an amide salt containing a pyridine ring structure; (3) Add 1 part of salt containing sulfonic acid group, 1 part of amide salt containing pyridine ring structure, 75 parts of nylon 66 salt and 60 parts of deionized water into the polymerization reactor, replace the air in the reactor with nitrogen for 3 times; turn on the heating, slowly raise the temperature to 215°C, keep the pressure at 2.0 MPa for condensation for 2 hours; continue to raise the temperature to 255°C, reduce the pressure to normal pressure 0 MPa after 0.5 hours; continue to raise the temperature to 270°C, evacuate to -0.01 MPa, keep the temperature and pressure for 1 hour, and obtain polyamide 66 containing sulfonic acid group and pyridine ring structure in the molecular chain, with a number average molecular weight of 17400 g / mol and a molecular structure of:

[0022] (4) Spinning polyamide 66 having a sulfonic acid group and a pyridine ring structure in the molecular chain at a spinning temperature of 280°C, a winding speed of 3500 m / min, and a stretching multiple of 4.5 to obtain a high-strength polyamide 66 fiber material.

[0023] After the fiber is woven into a slender sock tube by a hosiery machine, the color uptake rate is determined using acid red N-2RBL acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve of dyes" and evaluated according to "GB / T21881-2015 Determination of levelness of acid dyes".

[0024] Example 2 The method of the present invention is used to produce high-strength polyamide 66 fiber material, and the specific steps are as follows: (1) adding sodium 5-sulfoisophthalic acid and 1,6-hexanediamine in a molar ratio of 1:1.03 to water, reacting at room temperature, filtering, washing and drying after salt precipitation to obtain an amide salt containing a sulfonic acid group; (2) adding 2,5-pyridinedicarboxylic acid and 1,6-hexanediamine in a molar ratio of 1:1.03 into water, stirring at 70°C for 5 hours, filtering, washing and drying after salt precipitation to obtain an amide salt containing a pyridine ring structure; (3) Add 3 parts of salt containing sulfonic acid groups, 3 parts of amide salt containing pyridine ring structure, 100 parts of nylon 66 salt and 70 parts of deionized water into a polymerization reactor, replace the air in the reactor with nitrogen for 3 times; turn on the heating, slowly raise the temperature to 220°C, maintain the pressure at 1.8 MPa for condensation for 2.5 hours; continue to raise the temperature to 250°C, reduce the pressure to normal pressure 0 MPa after 0.8 hours; continue to raise the temperature to 275°C, evacuate to a pressure of -0.05 MPa, and maintain the temperature and pressure for 2 hours to obtain a polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain, with a number average molecular weight of 24200 g / mol and a molecular structure of:

[0025] (4) Spinning polyamide 66 having a sulfonic acid group and a pyridine ring structure in the molecular chain at a spinning temperature of 282°C, a winding speed of 3200 m / min, and a stretching multiple of 4.5 to obtain a high-strength polyamide 66 fiber material.

[0026] After the fibers are woven into long and thin socks on a hosiery machine, the color uptake rate is measured using NAVY MPA acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve for dyes" and evaluated according to "GB / T21881-2015 Determination of levelness of acid dyes".

[0027] Example 3 The method of the present invention is used to produce high-strength polyamide 66 fiber material, and the specific steps are as follows: (1) adding sodium 5-sulfoisophthalic acid and 1,6-hexanediamine in a molar ratio of 1:1.04 to water, reacting at room temperature, filtering, washing and drying after salt precipitation to obtain an amide salt containing a sulfonic acid group; (2) adding 2,6-pyridinedicarboxylic acid and 1,6-hexanediamine in a molar ratio of 1:1.04 into water, stirring at 80°C for 6 hours, filtering, washing and drying after salt precipitation to obtain an amide salt containing a pyridine ring structure; (3) Add 1 part of salt containing sulfonic acid group, 2 parts of amide salt containing pyridine ring structure, 100 parts of nylon 66 salt and 80 parts of deionized water into the polymerization reactor, replace the air in the reactor with nitrogen for 3 times; turn on the heating, slowly raise the temperature to 225°C, keep the pressure at 1.9 MPa for condensation for 3 hours; continue to raise the temperature to 250°C, reduce the pressure to normal pressure 0 MPa for 1 hour; continue to raise the temperature to 280°C, evacuate to the pressure of -0.08 MPa, keep the temperature and pressure for 2 hours, and obtain polyamide 66 containing sulfonic acid group and pyridine ring structure in the molecular chain, with a number average molecular weight of 23300 g / mol and a molecular structure of:

[0028] (4) Spinning polyamide 66 having a sulfonic acid group and a pyridine ring structure in the molecular chain at a spinning temperature of 285°C, a winding speed of 3000 m / min, and a stretching multiple of 4.5 to obtain a high-strength polyamide 66 fiber material.

[0029] After the fiber is woven into a slender sock tube by a hosiery machine, the color uptake rate is determined using acid red N-2RBL acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve of dyes" and evaluated according to "GB / T21881-2015 Determination of levelness of acid dyes".

[0030] Example 4 The method of the present invention is used to produce high-strength polyamide 66 fiber material, and the specific steps are as follows: (1) adding sodium 5-sulfoisophthalic acid and 1,6-hexanediamine in a molar ratio of 1:1.05 to water, reacting at room temperature, filtering, washing and drying after salt precipitation to obtain an amide salt containing a sulfonic acid group; (2) adding 2,6-pyridinedicarboxylic acid and 1,6-hexanediamine in a molar ratio of 1:1.05 into water, stirring at 90°C for 9 hours, filtering, washing and drying after salt precipitation to obtain an amide salt containing a pyridine ring structure; (3) Add 50 parts of salt containing sulfonic acid groups, 50 parts of amide salt containing pyridine ring structure, 100 parts of nylon 66 salt and 70 parts of deionized water into a polymerization reactor, replace the air in the reactor with nitrogen three times; turn on the heating, slowly raise the temperature to 235°C, keep the pressure at 2.0 MPa for condensation for 2 hours; continue to raise the temperature to 255°C, reduce the pressure to normal pressure 0 MPa after 0.5 hours; continue to raise the temperature to 273°C, evacuate to a pressure of -0.10 MPa, keep the temperature and pressure for 1 hour, and obtain polyamide 66 containing sulfonic acid groups and pyridine ring structure in the molecular chain, with a number average molecular weight of 17100 g / mol and a molecular structure of:

[0031] (4) Polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain and conventional polyamide 66 were mixed in a ratio of 1:36 and then spun. The spinning temperature was 288°C, the winding speed was 3000 m / min, and the stretching ratio was 5.0, thereby obtaining a high-strength polyamide 66 fiber material.

[0032] After the fibers are woven into long and thin socks on a hosiery machine, the color uptake rate is measured using NAVY MPA acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve for dyes" and evaluated according to "GB / T21881-2015 Determination of levelness of acid dyes".

[0033] Example 5 The method of the present invention is used to produce high-strength polyamide 66 fiber material, and the specific steps are as follows: (1) adding sodium 5-sulfoisophthalic acid and 1,6-hexanediamine in a molar ratio of 1:1.03 to water, reacting at room temperature, filtering, washing and drying after salt precipitation to obtain an amide salt containing a sulfonic acid group; (2) adding 2,6-pyridinedicarboxylic acid and 1,6-hexanediamine in a molar ratio of 1:1.03 into water, stirring at 80°C for 12 hours, filtering, washing and drying after salt precipitation to obtain an amide salt containing a pyridine ring structure; (3) Add 50 parts of salt containing sulfonic acid groups, 50 parts of amide salt containing pyridine ring structure, 100 parts of nylon 66 salt and 70 parts of deionized water into a polymerization reactor, replace the air in the reactor with nitrogen three times; turn on the heating, slowly raise the temperature to 225°C, keep the pressure at 1.8 MPa for condensation for 2.5 hours; continue to raise the temperature to 250°C, reduce the pressure to normal pressure 0 MPa after 0.8 hours; continue to raise the temperature to 278°C, evacuate to a pressure of -0.05 MPa, keep the temperature and pressure for 2 hours, and obtain polyamide 66 containing sulfonic acid groups and pyridine ring structure in the molecular chain, with a number average molecular weight of 17800 g / mol and a molecular structure of:

[0034] (4) Polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain and conventional polyamide 66 were mixed in a ratio of 1:145 and then spun. The spinning temperature was 292°C, the winding speed was 2900 m / min, and the stretching ratio was 5.2, thereby obtaining a high-strength polyamide 66 fiber material.

[0035] After the fiber is woven into a slender sock tube by a hosiery machine, the color uptake rate is determined using acid red N-2RBL acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve of dyes" and evaluated according to "GB / T21881-2015 Determination of levelness of acid dyes".

[0036] Example 6 The method of the present invention is used to produce high-strength polyamide 66 fiber material, and the specific steps are as follows: (1) adding sodium 5-sulfoisophthalic acid and 1,6-hexanediamine in a molar ratio of 1:1.04 to water, reacting at room temperature, filtering, washing and drying after salt precipitation to obtain an amide salt containing a sulfonic acid group; (2) adding 2,6-pyridinedicarboxylic acid and 1,6-hexanediamine in a molar ratio of 1:1.04 into water, stirring at 90°C for 8 hours, filtering, washing and drying after salt precipitation to obtain an amide salt containing a pyridine ring structure; (3) Add 50 parts of salt containing sulfonic acid groups, 50 parts of amide salt containing pyridine ring structure, 100 parts of nylon 66 salt and 80 parts of deionized water into a polymerization reactor, replace the air in the reactor with nitrogen three times; turn on the heating, slowly raise the temperature to 235°C, keep the pressure at 1.9 MPa for condensation for 3 hours; continue to raise the temperature to 245°C, reduce the pressure to normal pressure 0 MPa after 1 hour; continue to raise the temperature to 275°C, evacuate to a pressure of -0.10 MPa, keep the temperature and pressure for 3 hours, and obtain polyamide 66 containing sulfonic acid groups and pyridine ring structure in the molecular chain, with a number average molecular weight of 18300 g / mol and a molecular structure of:

[0037] (4) Polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain and conventional polyamide 66 were mixed in a ratio of 1:97 and spun at a spinning temperature of 295°C, a winding speed of 3000 m / min, and a stretching multiple of 5.5 to obtain a high-strength polyamide 66 fiber material.

[0038] After the fibers are woven into long and thin socks on a hosiery machine, the color uptake rate is measured using NAVY MPA acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve for dyes" and evaluated according to "GB / T21881-2015 Determination of levelness of acid dyes".

[0039] Comparative Example 1 Polyamide 66 with a number average molecular weight of 13000 g / mol was spun on a melt spinning machine at a spinning temperature of 285°C, a winding speed of 2500 m / min, and a stretching multiple of 3.0 to obtain polyamide 66 fiber. After the fiber was woven into a slender stocking tube by a hosiery machine, the color uptake rate was determined using acid red N-2RBL acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve of dyes" and evaluated according to "GB / T 21881-2015 Determination of levelness of acid dyes".

[0040] Comparative Example 2 Polyamide 66 with a number average molecular weight of 24000 g / mol was spun on a melt spinning machine at a spinning temperature of 300°C, a winding speed of 3000 m / min, and a stretching multiple of 5.5 to obtain a high-strength polyamide 66 fiber material. After the fiber was woven into a slender stocking tube on a hosiery machine, the color uptake rate was determined using NAVY MPA acid dye according to "GB / T23976.1-2009 Determination of color uptake rate curve of dyes" and evaluated according to "GB / T 21881-2015 Determination of levelness of acid dyes".

[0041] The mechanical properties and dyeing properties of the high-strength polyamide 66 fiber materials of various embodiments and comparative examples are shown in Table 1 below: Table 1 Mechanical properties and dyeing properties of high-strength polyamide 66 fiber materials

[0042] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A high-strength polyamide 66 fiber material, characterized in that: The raw material is polyamide 66 containing sulfonic acid groups and pyridine rings in the molecular chain, and its structural formula is as follows: ； Where m is 4~10, n is 4~10, x is 1~35, y is 32~146, z is 1~35, and the structure of R' is as follows: ； The structure of R is as follows: 。 2. A method for preparing a high-strength polyamide 66 fiber material, characterized in that: The following steps are involved: (1) adding a dibasic acid containing a sulfonic acid group and an aliphatic diamine to water or ethanol in a certain ratio, and performing a salt-forming reaction at room temperature. After the salt is precipitated, filtering, washing, and drying are performed to obtain an amide salt containing a sulfonic acid group; (2) adding a pyridine ring structure compound and an aliphatic dibasic acid or diamine to water or ethanol in a certain proportion, stirring at 60-90°C for 1-12 hours, filtering, washing and drying after the salt is precipitated to obtain an amide salt containing a pyridine ring structure; (3) Add 1-50 parts of salt containing sulfonic acid groups, 1-50 parts of amide salt containing pyridine ring structure, 75-100 parts of nylon 66 salt, and 60-80 parts of deionized water into a polymerization reaction kettle, and replace the air in the kettle with nitrogen for 3 times; turn on the heating, slowly raise the temperature to 215-235°C, and maintain the pressure at 1.8-2.0 MPa for condensation for 2-3 hours; continue to raise the temperature to 245-255°C, and reduce the pressure to normal pressure 0 MPa after 0.5-1 hour; continue to raise the temperature to 270-280°C, evacuate to a pressure of -0.01-0.10 MPa, and maintain the temperature and pressure for 1-3 hours to obtain polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain; (4) Polyamide 66 containing sulfonic acid groups and pyridine ring structures or polyamide 66 containing sulfonic acid groups and pyridine ring structures and conventional polyamide 66 are mixed in a certain proportion and then spun in a melt spinning machine to obtain a high-strength polyamide 66 fiber material.

3. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: In step (1), the sulfonic acid group-containing compound is sodium 5-sulfonate of isophthalic acid; and the aliphatic diamine is a straight-chain aliphatic diamine having 4 to 10 carbon atoms.

4. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: In step (1), the dibasic acid containing a sulfonic acid group and the aliphatic diamine are subjected to a salt-forming reaction in a molar ratio of 1:1.02-1.

05.

5. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: In step (2), the pyridine ring structure-containing compound includes a pyridine ring-containing dibasic acid and a pyridine ring-containing diamine. The pyridine ring-containing dibasic acid includes one or more of 2,6-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2,3-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, and 3,4-pyridinedicarboxylic acid. The pyridine ring-containing diamine includes one or more of 2,6-diaminopyridine, 2,5-diaminopyridine, 2,4-diaminopyridine, 2,3-diaminopyridine, 3,5-diaminopyridine, and 3,4-diaminopyridine. The aliphatic dibasic acid is a straight-chain aliphatic dibasic acid having 4 to 12 carbon atoms. The aliphatic diamine is a straight-chain aliphatic diamine having 4 to 10 carbon atoms.

6. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: In step (2), when the pyridine ring structure-containing compound is a diamine structure, the pyridine ring-containing diamine and the aliphatic dibasic acid are subjected to a salt-forming reaction at a molar ratio of 1.02 to 1.05:1; when the pyridine ring structure-containing compound is a dibasic acid structure, the pyridine ring-containing dibasic acid and the aliphatic diamine are subjected to a salt-forming reaction at a molar ratio of 1:1.02 to 1.

05.

7. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: In step (3), the number average molecular weight of polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain is 17000~24000g / mol.

8. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: In step (4), when x is 1-4, y is 70-146, and z is 1-4, the polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain can be spun alone. When x is 4-35, y is 32-70, and z is 4-35, the polyamide 66 containing sulfonic acid groups and pyridine ring structures in the molecular chain is mixed with conventional polyamide 66 in a ratio of 1:36-196 and then spun.

9. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: The melt spinning conditions in step (4) are a temperature of 280-295° C., a winding speed of 2500-3500 m / min, and a stretching ratio of 4.5-5.

5.

10. The method for preparing a high-strength polyamide 66 fiber material according to claim 2, characterized in that: The prepared high-strength polyamide 66 fiber material has a single-filament fineness of 0.9-1.4 dtex, a breaking strength of 6.5-8.2 cN / dtex, an elongation at break of 16.4-24.7%, and a woven fabric with dyeing uniformity of level 5, a dyeing rate of 98.1-99.2%, and a K / S value of 24.5-28.5.

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