Preparation method of enhanced dyeing high-carboxyl nylon master batch and high-carboxyl nylon yarn

Abstract

The invention discloses a preparation method of a dyeing-enhanced high-carboxyl nylon master batch, which comprises the following steps: step 1, adding nylon 6 slices into a main feeding position of an extruder, and adding organic acid into a side feeding position of the extruder; 2, controlling the temperature of each section of temperature zone of the extruder to melt and blend the nylon 6 slices and the organic acid to form a blend; and step 3, carrying out bracing, water tank cooling, grain-sized vibration screening and vacuum constant-temperature drying on the blend to obtain the high-carboxyl nylon 6 master batch. The invention further discloses a preparation method of the high-carboxyl nylon yarn. The high-carboxyl nylon 6 master batch is obtained in a blending granulation mode of the organic acid and the nylon matrix, then the high-carboxyl nylon fiber is prepared, in the dyeing process, the high-carboxyl nylon 6 fiber slowly releases free H < + > in a dye liquor, the acid environment of the dye liquor is enhanced, and therefore the dye uptake of the nylon 6 fiber in acid dye is increased. The high-carboxyl nylon yarn prepared by the invention is beneficial to environmental protection and lower in treatment cost.

Description

Technical Field

[0001] The invention relates to the technical field of dyeing, and in particular to a preparation method of a high-carboxyl nylon masterbatch for enhanced dyeing and a high-carboxyl nylon yarn. Background Art

[0002] With the rising sports craze in recent years, the sportswear market has developed rapidly, and nylon fabrics and stretch fibers are widely used in outdoor clothing and other products. Acid dyes are widely used in nylon fibers, which have a complete color spectrum and bright colors. In the process of nylon fiber dyeing, pH value is one of the most important factors affecting the acid dye dyeing of fibers. Adding acid will promote dyeing, but it will cause a greater burden on the treatment of printing and dyeing wastewater, and at the same time bring pressure on rising production costs.

[0003] The Chinese patent document with publication number CN118029174A discloses a method for dyeing nylon fibers, which performs secondary dyeing and color fixation by adjusting the pH value of the residual liquid, adding acid dyes, etc., to improve the color fixation rate, color fastness and dyeing depth on the nylon fiber from the dye liquor end. The addition of multiple processes not only makes the operation complicated, but also the problem of waste liquid pollution still exists and has not been solved or improved. The Chinese patent document with publication number CN113279271A discloses an acid dye dyeing auxiliary and a preparation method thereof, which adjusts the pH value of the dye liquor by glacial acetic acid solution and eliminates the use of a leveling agent to improve the dye uptake rate. Although this method can improve the dye uptake rate, the addition of glacial acetic acid to the dye liquor formula still places a great burden on the subsequent waste liquid treatment.

[0004] In summary, the existing acid dyeing wastewater is seriously polluted and no effective improvement measures have been taken. Although adding acid from the dyeing liquid can achieve a dyeing-promoting effect, the problem of difficulty in wastewater treatment still exists. Summary of the invention

[0005] Based on the above problems existing in the prior art, one purpose of the embodiments of the present application is to provide a method for preparing a high-carboxyl nylon masterbatch for enhanced dyeing, which is prepared by blending an organic acid with a nylon matrix to obtain a high-carboxyl nylon 6 masterbatch, which slowly releases free H + , the dyeing rate is improved, and the COD content in the waste liquid after dyeing is significantly reduced, which is beneficial to environmental protection, reduces pollution, and has lower processing costs.

[0006] The second purpose of the embodiment of the present application is to provide a method for preparing high-carboxyl nylon yarn. The high-carboxyl nylon 6 yarn prepared by the method can improve the dyeing rate of nylon 6 fiber in acid dyes, and the COD content in the waste liquid after dyeing is significantly lower than that in the dyeing liquid after conventional nylon 6 fiber dyeing, which is in line with the concept of green and sustainable development.

[0007] The technical solution adopted by the present application to solve the technical problem is: a method for preparing a high-carboxyl nylon masterbatch for enhanced dyeing, comprising the following steps:

[0008] Step 1: Add nylon 6 chips to the main feed position of the extruder, and add organic acid to the side feed position of the extruder;

[0009] Step 2, controlling the temperature of each temperature zone of the extruder to melt-blend the nylon 6 chips and the organic acid to form a blend;

[0010] Step 3, the blend is subjected to strip drawing, water tank cooling, pelletizing vibration screening and vacuum constant temperature drying to obtain high carboxyl nylon 6 masterbatch.

[0011] Furthermore, in step 1, nylon 6 chips account for 99% and organic acid accounts for 1%.

[0012] Furthermore, in step 1, the organic acid is trimesic acid or succinic acid.

[0013] Furthermore, the extruders in step 1 and step 2 are twin-screw extruders.

[0014] Further, in step 2, the temperatures of the temperature zones of the extruder are: the temperature of the first zone is 220°C; the temperature of the second to fifth zones is 215-220°C, the temperature of the sixth to eighth zones is 205-210°C, the temperature of the ninth zone is 190-200°C, the temperature of the tenth zone is 180-190°C, the temperature of the eleventh zone is 170-180°C, and the temperature of the die head is 215-220°C.

[0015] The technical solution adopted by the present application to solve the technical problem is: a method for preparing high-carboxyl nylon yarn, comprising the following steps:

[0016] Step S1, adding nylon 6 chips to the main feed position of the extruder, and adding organic acid to the side feed position of the extruder;

[0017] Step S2, controlling the temperature of each temperature zone of the extruder to melt-blend the nylon 6 chips and the organic acid to form a blend;

[0018] Step S3, the blend is subjected to strip drawing, water tank cooling, pelletizing vibration screening and vacuum constant temperature drying to obtain high carboxyl nylon 6 masterbatch;

[0019] Step S4, preparing high carboxyl nylon 6 fiber by mixing high carboxyl nylon 6 masterbatch and nylon 6 chips in a mass ratio of 1:1.

[0020] Furthermore, the method also includes step S5, in which the high-carboxyl nylon 6 fiber is dyed. The dyeing process is to first prepare an acidic dye solution for nylon, then heat the acidic dye solution for nylon, and then dye the high-carboxyl nylon 6 fiber in the acidic dye solution for nylon. Finally, the fiber is rinsed with deionized water and air-dried in a natural state to obtain dyed high-carboxyl nylon 6 fiber.

[0021] Further, in step S5, the volume of deionized water and the weight of the acid dye are in a ratio of 1:0.003 to prepare an acid dye solution for nylon.

[0022] Further, in step S1, nylon 6 chips account for 99% and organic acid accounts for 1%; in step S1, the organic acid is trimesic acid or succinic acid; and the extruders in step S1 and step S2 are twin-screw extruders.

[0023] Further, in step S2, the temperatures of the temperature zones of the extruder are: the temperature of the first zone is 220°C; the temperature of the second to fifth zones is 215-220°C, the temperature of the sixth to eighth zones is 205-210°C, the temperature of the ninth zone is 190-200°C, the temperature of the tenth zone is 180-190°C, the temperature of the eleventh zone is 170-180°C, and the temperature of the head zone is 215-220°C.

[0024] The beneficial effects of the present application are as follows: the present invention adopts the method of blending organic acid with nylon matrix to obtain high-carboxyl nylon 6 masterbatch, and then obtains high-carboxyl nylon fiber. During the dyeing process, the high-carboxyl nylon 6 fiber slowly releases free H + , enhancing the acidic environment of the dye solution, thereby enhancing the dye uptake rate of nylon 6 fiber in acid dyes. The novel nylon 6 fiber with high dye uptake rate prepared by the present invention has a significantly lower COD content in the waste liquid after dyeing than the conventional nylon 6 fiber dye solution after dyeing, which is beneficial to environmental protection, pollution reduction, and lower processing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a comparison diagram of the dyeing effects of Example 1 and Comparative Example 1;

[0026] Figure 2 This is a comparison chart of the dyeing effects of Example 2 and Comparative Example 2. DETAILED DESCRIPTION

[0027] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0028] The method for preparing a high-carboxyl nylon masterbatch for enhanced dyeing of the present invention comprises the following steps:

[0029] Step 1, adding nylon 6 chips to the main feeding position of the extruder, and adding organic acid at the side feeding position of the extruder; Step 2, controlling the temperature of each temperature zone of the extruder to melt-blend the nylon 6 chips and the organic acid to form a blend; Step 3, the blend is subjected to strip drawing, water tank cooling, pelletizing vibration screening and vacuum constant temperature drying to obtain a high-carboxyl nylon 6 masterbatch.

[0030] Thus, the present invention relates to a method for preparing a high-carboxyl nylon masterbatch for enhanced dyeing. The present invention adopts a method for blending and granulating an organic acid with a nylon matrix to obtain a high-carboxyl nylon 6 masterbatch, and then obtains a high-carboxyl nylon fiber. During the dyeing process, the high-carboxyl nylon 6 fiber slowly releases free H + , enhance the acidic environment of the dye solution, thereby improving the dyeing rate of nylon 6 fiber in acid dyes.

[0031] In a preferred embodiment of the present invention, in step 1, nylon 6 chips account for 99% and organic acid accounts for 1%. In step 1, the organic acid is trimesic acid or succinic acid, and in step 2, the temperatures of the temperature zones of the extruder are: the temperature of the first zone is 220°C; the temperature of the second to fifth zones is 215-220°C, the temperature of the sixth to eighth zones is 205-210°C, the temperature of the ninth zone is 190-200°C, the temperature of the tenth zone is 180-190°C, the temperature of the eleventh zone is 170-180°C, and the temperature of the die head is 215-220°C.

[0032] The setting of the heating temperature of the extruder during the production process is very critical, and different heating section temperature settings will affect the quality and production capacity of the product. The present invention divides the extruder into eleven temperature zones, each of which corresponds to a corresponding temperature. After testing, the end carboxyl group of the high-carboxyl nylon masterbatch prepared by the method is significantly improved, at least 3 times that of conventional slices.

[0033] Furthermore, the extruders in step 1 and step 2 are preferably twin-screw extruders.

[0034] The present invention also discloses a method for preparing high-carboxyl nylon yarn, comprising the following steps:

[0035] Step S1, adding nylon 6 chips to the main feeding position of the extruder, and adding organic acid to the side feeding position of the extruder; step S2, controlling the temperature of each temperature zone of the extruder to melt-blend nylon 6 chips and organic acid to form a blend; step S3, the blend is subjected to drawing, water tank cooling, pelletizing vibration screening and vacuum constant temperature drying to obtain high-carboxyl nylon 6 masterbatch; step S4, high-carboxyl nylon 6 masterbatch and nylon 6 chips are mixed in a mass ratio of 1:1 to obtain high-carboxyl nylon 6 fiber. The new nylon 6 fiber with high dyeing rate prepared by the present invention has a significantly lower COD content in the waste liquid after dyeing than the conventional nylon 6 fiber dyeing liquid, which is beneficial to environmental protection, reduces pollution, and has a lower processing cost. It is in line with the concept of green and sustainable development.

[0036] In a preferred embodiment of the present invention, step S5 is further included, and step S5 is to dye the high-carboxyl nylon 6 fiber. The dyeing process is to first prepare an acidic dye solution for nylon, then heat the acidic dye solution for nylon, and then dye the high-carboxyl nylon 6 fiber in the acidic dye solution for nylon, and finally rinse with deionized water, and air-dry in a natural state to obtain the dyed high-carboxyl nylon 6 fiber. Further, in step S5, the volume of deionized water and the weight of the acid dye are 1:0.003 to prepare the acidic dye solution for nylon.

[0037] Further, in step S1, nylon 6 chips account for 99% and organic acid accounts for 1%; in step S1, the organic acid is trimesic acid or succinic acid; the extruders in step S1 and step S2 are twin-screw extruders. In step S2, the temperatures of the temperature zones of the extruder are: the temperature of the first zone is 220°C; the temperature of the second to fifth zones is 215-220°C, the temperature of the sixth to eighth zones is 205-210°C, the temperature of the ninth zone is 190-200°C, the temperature of the tenth zone is 180-190°C, the temperature of the eleventh zone is 170-180°C, and the temperature of the head zone is 215-220°C.

[0038] Thus, the high carboxyl nylon 6 fiber prepared by this method has a higher terminal carboxyl content than the fiber of the same specification, indicating that the co-granulation of organic acid and nylon matrix significantly increases the terminal carboxyl of the masterbatch.

[0039] The following specific examples are used to further illustrate the properties of the prepared high carboxyl nylon masterbatch and high carboxyl nylon yarn.

[0040] Example 1: Take 3.0 g of high-carboxyl nylon 6 fiber, use a measuring cup to take 150 mL of acidic dye solution and put it into a glass beaker, which is placed in an iron basin filled with tap water; turn on the induction cooker switch, 2000 W power, wait for 3 minutes until the water in the iron basin is warm, add the fiber to the glass beaker filled with dye solution; after uniform dyeing for 30 minutes under stirring, rinse with deionized water for 1 minute; air-dry under natural conditions, and observe the dyeing condition of high-carboxyl nylon 6 fiber.

[0041] Example 2: Take 3.0 g of high-carboxyl nylon 6 fiber, use a measuring cup to take 150 mL of acidic dye solution and put it into a glass beaker, and place it in an iron basin filled with tap water; turn on the induction cooker switch, 2000 W power, wait for 3 minutes until the water in the iron basin is warm, add the fiber to the glass beaker filled with dye solution; after uniform dyeing for 15 minutes under stirring, rinse with deionized water for 1 minute; air-dry under natural conditions, and observe the dyeing condition of high-carboxyl nylon 6 fiber.

[0042] Comparative Example 1: Take 3.0 g of nylon 6 fiber, use a measuring cup to take 150 mL of acidic dye solution and put it into a glass beaker, and place it in an iron basin filled with tap water; turn on the induction cooker switch, 2000 W power, wait for 3 minutes until the water in the iron basin is warm, and add the fiber to the glass beaker filled with dye solution; after uniformly dyeing for 30 minutes under stirring, rinse with deionized water for 1 minute; air-dry under natural conditions, and observe the dyeing condition of nylon 6 fiber.

[0043] Comparative Example 2: Take 3.0 g of nylon 6 fiber, use a measuring cup to take 150 mL of acidic dye solution and put it into a glass beaker, and place it in an iron basin filled with tap water; turn on the induction cooker switch, 2000 W power, wait for 3 minutes until the water in the iron basin is warm, and add the fiber to the glass beaker filled with dye solution; after dyeing evenly for 15 minutes under stirring, rinse with deionized water for 1 minute; air-dry under natural conditions, and observe the dyeing condition of nylon 6 fiber.

[0044] Table 1 Masterbatch detection

[0045]

[0046] Table 2 Fiber detection

[0047] Test items High carboxyl nylon 6 fiber Nylon 6 fiber Specification FDY-SD 50D / 34F FDY-SD 50D / 34F H3BTC effective content 0.5％ 0％ Terminal amino group (mmol / kg) 51.75 47.46 Terminal carboxyl group (mmol / kg) 130.89 64.21

[0048] From the results of masterbatch detection, the terminal carboxyl content of the masterbatch prepared by the present invention is 207.65mmol / kg, which is significantly improved, at least 3 times that of conventional slices (40-50mmol / kg). The terminal carboxyl content of the prepared high-carboxyl nylon 6 fiber is 130.89mmol / kg, which is higher than the terminal carboxyl content of the same specification fiber by 64.21mmol / kg. This shows that the co-granulation of organic acid and nylon matrix significantly increases the terminal carboxyl content of the masterbatch.

[0049] Table 3 Fiber dyeing and waste liquid

[0050] project unit Example 1 Comparative Example 1 Example 2 Comparative Example 2 Dyeing rate / 96％ 91％ 83％ 78％ COD of wastewater after dyeing mg / L 704.5 817.5 769.5 846.5 Ammonia nitrogen in waste liquid after dyeing mg / L 3.2 3.10 3.2 3.10 pH value of wastewater after dyeing / 6.3 7.8 6.5 7.9

[0051] Figure 1 This is a comparison chart of the dyeing effects of Example 1 and Comparative Example 1. Figure 2 This is a comparison chart of the dyeing effects of Example 2 and Comparative Example 2. Figure 1and Figure 2 As shown in the figure, from the results of fiber dyeing, the dyeing rate is: Example 1>Comparative Example 1>Example 2>Comparative Example 2. Combined with the actual dyeing conditions of the two groups of dyed yarns, it is shown that the high-carboxyl nylon 6 fiber has a higher dyeing rate than the conventional nylon 6 fiber in the same concentration of acidic dye solution, that is, the organic acid effectively improves the dyeing rate of nylon 6 fiber.

[0052] From the test results of the waste liquid after dyeing, the COD content is as follows: Example 1 < Example 2 < Comparative Example 1 < Comparative Example 2. The COD content of the waste liquid after dyeing of high-carboxyl nylon 6 fiber is significantly lower than that of conventional nylon 6 fiber, and the processing cost is lower.

[0053] In summary, the present invention adopts the method of blending organic acid with nylon matrix to obtain high-carboxyl nylon 6 masterbatch, and then obtains high-carboxyl nylon fiber. During the dyeing process, the high-carboxyl fiber slowly releases free H + , enhancing the acidic environment of the dye solution, thereby enhancing the dye uptake rate of nylon 6 fiber in acid dyes. The novel nylon 6 fiber with high dye uptake rate prepared by the present invention has a significantly lower COD content in the waste liquid after dyeing than the conventional nylon 6 fiber dye solution after dyeing, which conforms to the concept of sustainable development and has a lower processing cost.

[0054] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for preparing a high-carboxyl nylon masterbatch for enhanced dyeing, characterized in that: The following steps are involved: Step 1: Add nylon 6 chips to the main feed position of the extruder, and add organic acid to the side feed position of the extruder; Step 2, controlling the temperature of each temperature zone of the extruder to melt-blend the nylon 6 chips and the organic acid to form a blend; Step 3, the blend is subjected to strip drawing, water tank cooling, pelletizing vibration screening and vacuum constant temperature drying to obtain high carboxyl nylon 6 masterbatch.

2. The method for preparing the high-carboxyl nylon masterbatch for enhanced dyeing according to claim 1, characterized in that: In step 1, nylon 6 chips account for 99% and organic acid accounts for 1%.

3. The method for preparing the high-carboxyl nylon masterbatch for enhanced dyeing according to claim 1, characterized in that: In step 1, the organic acid is trimesic acid or succinic acid.

4. The method for preparing the high-carboxyl nylon masterbatch for enhanced dyeing according to claim 1, characterized in that: The extruders in step 1 and step 2 are twin-screw extruders.

5. The method for preparing the dyeing-enhanced high-carboxyl nylon masterbatch according to claim 1, characterized in that: In step 2, the temperatures of the temperature zones of the extruder are: the temperature of the first zone is 220°C; the temperature of the second to fifth zones is 215-220°C, the temperature of the sixth to eighth zones is 205-210°C, the temperature of the ninth zone is 190-200°C, the temperature of the tenth zone is 180-190°C, the temperature of the eleventh zone is 170-180°C, and the temperature of the die head is 215-220°C.

6. A method for preparing high-carboxyl nylon yarn, characterized in that: The following steps are involved: Step S1, adding nylon 6 chips to the main feed position of the extruder, and adding organic acid to the side feed position of the extruder; Step S2, controlling the temperature of each temperature zone of the extruder to melt-blend the nylon 6 chips and the organic acid to form a blend; Step S3, the blend is subjected to strip drawing, water tank cooling, pelletizing vibration screening and vacuum constant temperature drying to obtain high carboxyl nylon 6 masterbatch; Step S4, preparing high carboxyl nylon 6 fiber by mixing high carboxyl nylon 6 masterbatch and nylon 6 chips in a mass ratio of 1:

1.

7. The method for preparing high-carboxyl nylon yarn according to claim 6, characterized in that: The method also includes step S5, wherein step S5 is to dye the high-carboxyl nylon 6 fiber. The dyeing process is to first prepare an acidic dye solution for nylon, then heat the acidic dye solution for nylon, and then place the high-carboxyl nylon 6 fiber in the acidic dye solution for nylon for dyeing. Finally, the fiber is rinsed with deionized water and air-dried in a natural state to obtain the dyed high-carboxyl nylon 6 fiber.

8. The method for preparing high-carboxyl nylon yarn according to claim 6, characterized in that: In step S5, the volume of deionized water and the weight of the acid dye are in a ratio of 1:0.003 to prepare an acid dye solution for nylon.

9. The method for preparing high-carboxyl nylon yarn according to claim 6, characterized in that: In step S1, nylon 6 chips account for 99% and organic acid accounts for 1%; in step S1, the organic acid is trimesic acid or succinic acid.

10. The method for preparing high-carboxyl nylon yarn according to claim 9, characterized in that: In step S2, the temperatures of the temperature zones of the extruder are: the temperature of the first zone is 220°C; the temperature of the second to fifth zones is 215-220°C, the temperature of the sixth to eighth zones is 205-210°C, the temperature of the ninth zone is 190-200°C, the temperature of the tenth zone is 180-190°C, the temperature of the eleventh zone is 170-180°C, and the temperature of the die head is 215-220°C.

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