A method of cold rolling a modified fiber

Abstract

The application relates to the technical field of modified fibers, and discloses a cold-rolling modified fiber method, which comprises the following steps: S1, modifying agents and alkali solutions are respectively heated to 40-60 DEG C; S2, the modifying agents and the alkali solutions are injected into a dyeing tank according to a weight ratio of 3-5:1, and are mixed and stirred; S3, fibers are webbed and subjected to cold-rolling treatment, the liquid retention rate of the fibers is controlled to be 150-170%, and the fibers are wound; S4, the wound fibers are wrapped and sealed by plastic films, and are stored by cold piling; and S5, the fibers after cold piling are washed in a washing tank containing an alkali solution, and are subjected to acid pickling and hot water washing, so that the modified fibers are obtained. The application adopts a specific modified fiber preparation method, effectively solves the problem that the fiber modification effect is poor in a low-temperature environment, the modification effect is excellent, and the modified fibers have excellent dyeing effects.

Description

Technical Field

[0001] This application relates to the field of modified fiber technology, and in particular to a method for cold-rolling modified fibers. Background Technology

[0002] Salt-free and alkali-free dyeing technology is a novel green dyeing process developed to address the challenges of large-volume and high-salt-content wastewater discharge from reactive dyeing. By modifying fibers, salt-free and alkali-free dyeing can be achieved. After modification, dyeing can proceed without the addition of salt or alkali, solving the high-salt problem of dyeing wastewater at its source and achieving environmental protection. The modified fibers / yarns / fabrics can be dyed without salt or alkali, and are suitable for yarn spinning, denim, hosiery, and absorbent fabrics, with very wide market applications.

[0003] Due to the high cost of modifying traditional dyeing vats, many printing and dyeing plants have introduced continuous cold pad-batch equipment for modification, which can significantly reduce modification costs (2000 RMB / T) and make market application possible.

[0004] However, continuous cold rolling mills operate at ambient temperatures, which are highly variable and significantly affected by weather conditions. This means the reactivity of the modifier with the fiber is greatly influenced by temperature, making it difficult to guarantee the stability of the modification effect. Especially in winter, the modification effect differs greatly from that in summer due to lower temperatures, leading to increased costs. Considering that winters in most parts of my country last 4-5 months, adding insulation and heating devices to factories and equipment would require a very high overall investment, which many factories cannot afford, potentially causing them to be unable to produce during the winter.

[0005] Therefore, there is an urgent need to develop a method that achieves excellent fiber modification effects at low temperatures. Summary of the Invention

[0006] In order to solve at least one of the above-mentioned technical problems and to develop a method for stable fiber modification and excellent modification effect at low temperature, this application provides a method for cold rolling modified fibers.

[0007] On the one hand, this application provides a method for cold-rolled modified fibers, comprising the following steps: S1. Heat the modifier and alkaline solution to 40-60℃ respectively; S2. Add the modifier and alkaline solution to the dyeing tank at a weight ratio of 3-5:1, and mix and stir. S3. After the fibers are formed into a web, they are immersed in a dyeing tank. The liquid content of the fibers is controlled to be 150-170% by a rolling mill, and then wound up. S4. Wrap the wound fibers in plastic film, seal them, and store them in a cold stack. S5. After the cold-piled fibers are washed in a water washing tank containing an alkaline solution, they are then acid-washed and washed with hot water to obtain the modified fibers.

[0008] By adopting the above technical solutions, this application employs a specific method for preparing modified fibers, effectively solving the problem of poor fiber modification effect in low-temperature environments. The modification effect is excellent, and the dyeing fixation rate of the modified fibers is high. This application uses a specific ratio of modifier and alkaline solution, and a special alkaline solution and combination to ensure good reactivity between the modifier and the fiber in low-temperature environments. This application controls a specific liquid carrying rate to effectively ensure uniform water content and optimal reactivity of the fibers. In S5 of this application, an alkaline solution is also added to the washing tank, which can further improve the fiber modification effect.

[0009] Optionally, the modifier may be selected from polycaprolactone-hydroxyapatite composite solution.

[0010] Optionally, the polycaprolactone-hydroxyapatite composite solution is prepared from polycaprolactone, nano-hydroxyapatite, and ethanol in a weight ratio of 1:0.5:2.

[0011] Optionally, in S1 and S5, the base is selected from one or more of sodium hydroxide and potassium hydroxide.

[0012] By adopting the above technical solution, this application uses specific modifiers and specific alkalis to effectively promote the wettability and polarity of the fiber surface, thereby improving the fiber's adsorption capacity and durability for dyes.

[0013] Optionally, in S1, the concentration of the alkaline solution is 30-40 g / L.

[0014] Optionally, in S4, the cold stacking time is 20-24 hours.

[0015] Optionally, in S4, the cold reactor temperature is -5 to 35°C.

[0016] Optionally, in step S5, the concentration of the alkaline solution is 2-10 g / L.

[0017] Optionally, in step S5, the temperature of the water washing tank containing the alkaline solution is 60-90°C.

[0018] Optionally, the fiber may be subjected to ultrasonic pretreatment in an ionic liquid before cold rolling.

[0019] Optionally, the ultrasonic pretreatment process involves an ultrasonic frequency of 20-50 kHz and an ultrasonic time of 4-10 min.

[0020] Optionally, the ionic liquid is an alkyl imidazoline organosilicon quaternary ammonium salt solution.

[0021] By adopting the above technical solution, this application can further optimize the fiber modification effect and improve dyeing performance and durability by performing ultrasonic pretreatment in an ionic liquid, combined with appropriate ultrasonic frequency and time control and suitable ionic liquid selection. During ultrasonic treatment in the ionic liquid, the ionic liquid can interact with the fiber surface, improving the wettability and polarity of the fiber, thereby promoting the adsorption and diffusion of dyes in the fiber. Furthermore, ultrasonic pretreatment helps accelerate the penetration and diffusion of the ionic liquid, further enhancing the modification effect on the fiber surface, while ensuring that the ionic liquid forms a uniform coating on the fiber surface. Moreover, the use of specific alkyl imidazoline organosilicon quaternary ammonium salts has good wettability and permeability, enabling the formation of a stable interface with the fiber surface, thus improving dyeing performance and durability.

[0022] In summary, the present invention has at least one of the following beneficial technical effects: 1. This application employs a specific method for preparing modified fibers, which effectively solves the problem of poor fiber modification effect in low-temperature environments, overcomes winter limitations, and facilitates the marketization of modified products; 2. This application controls a specific liquid carrying rate to effectively and uniformly modify the fiber, and uses a specific ratio of modifier and alkaline solution to effectively form a uniform film covering the fiber surface. This film can form chemical bonds or physical adsorption with the dye, thereby enhancing the binding force between the fiber and the dye and improving the durability and stability of dyeing. 3. In S5 of this application, an alkaline solution is also added to the washing tank, which can further improve the fiber modification effect. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the embodiments. Specific Implementation

[0024] The raw materials used in this application are as follows. Unless otherwise specified, all raw materials used in this application are commercially available: Polycaprolactone: purity 99.9%; Ethanol: 95% purity; Sodium hydroxide: 99% purity; Potassium hydroxide: purity 99.5%; Polyphosphoric acid: 99% purity; Viscose fiber: Nangong Yingyue Cashmere Co., Ltd., Item No. Yingyue Cashmere; The plastic film is a low-density polyethylene film: brand: Maoming Petrochemical, item number: 2426H; Nano-hydroxyapatite: CAS No.: 1306-06-5, Wuhan Penglei Biotechnology Co., Ltd.; Alkyl imidazoline organosilicon quaternary ammonium salt solution: The alkyl imidazoline organosilicon quaternary ammonium salt prepared according to Example 2 of CN108948068A was dissolved in deionized water, mixed and stirred to prepare an alkyl imidazoline organosilicon quaternary ammonium salt solution, wherein the weight of deionized water was 10 times the weight of alkyl imidazoline organosilicon quaternary ammonium salt. Preparation method of polycaprolactone-hydroxyapatite composite solution: dissolve polycaprolactone in ethanol, then add nano-hydroxyapatite and mix and stir to prepare polycaprolactone-hydroxyapatite composite solution, wherein the weight ratio of polycaprolactone, nano-hydroxyapatite and ethanol is 1:0.5:2.

[0025] Testing items and methods: Fixation rate: The fixation rate was tested according to the standard GB / T 2391-2014 "Determination of Fixation Rate of Reactive Dyes"; the modified fiber prepared in this application was dyed with red BES (Shanghai Taojia Chemical Dye Co., Ltd.) dye at a concentration of 3wt% and 8wt% at a temperature of 25℃, a liquor ratio of 1:30, and a time of 5min. Color absorption time of the absorbent sheet: Red BES (Shanghai Taojia Chemical Dye Co., Ltd.) was prepared into a dye with a concentration of 0.025%. Three 200mL portions of dye were measured and placed into measuring cups. The modified fiber prepared in this application was used to prepare absorbent sheets. 5g of absorbent sheet was placed in the first cup, and the red absorption time was recorded. Then, the absorbent sheet was dehydrated, dried, and placed in the second cup to record the absorption time. The absorbent sheet was then dehydrated, dried, and placed in the third cup to record the absorption time.

[0026] Examples 1-4 Example 1 A method for cold-rolled modified fibers includes the following steps: S1. Heat the modifier and alkaline solution to 40℃ respectively; S2. Add the modifier and alkaline solution to the dyeing tank at a weight ratio of 3:1, and mix and stir. S3. After the fiber is formed into a web, it is immersed in the dyeing tank. The liquid content of the fiber is controlled to be 150% by the rolling mill, and then it is wound up. S4. Wrap the wound fibers in plastic film, seal them, and store them in a cold stack. S5. After the cold-piled fibers are washed in a water washing tank containing an alkaline solution, they are then acid-washed and washed in hot water at a temperature of 50°C to obtain modified fibers. Among them, S1, S2, S3, S4 and S5 were all carried out at an ambient temperature of -5℃; In S1, the modifier is selected from polycaprolactone-hydroxyapatite composite solution; in S1 and S5, the alkaline solution is selected from potassium hydroxide solution; in S1, the concentration of the alkaline solution is 30 g / L. In S3, the fiber is viscose fiber; In S4, the cold stacking time is 20 hours and the cold stacking temperature is -5°C; the plastic film is a low-density polyethylene film. In S5, the concentration of the alkaline solution is 2 g / L; In S5, the temperature in the water washing tank containing the alkaline solution is 60℃.

[0027] Example 2 A method for addressing the poor performance of cold-rolled modified fibers in winter includes the following steps: S1. Heat the modifier and alkaline solution to 42℃ respectively; S2. Add the modifier and alkaline solution to the dyeing tank at a weight ratio of 4:1, and mix and stir. S3. After the fiber is formed into a web, it is immersed in the dyeing tank. The liquid content of the fiber is controlled to be 160% by the rolling mill, and then it is wound up. S4. Wrap the wound fibers in plastic film, seal them, and store them in a cold stack. S5. After the cold-piled fibers are washed in a water washing tank containing an alkaline solution, they are then acid-washed and washed in hot water at a temperature of 50°C to obtain modified fibers. Among them, S1, S2, S3, S4 and S5 were all carried out at an ambient temperature of -5℃; In S1, the modifier is selected from polycaprolactone-hydroxyapatite composite solution; in S1 and S5, the alkaline solution is selected from sodium hydroxide solution; in S2, the concentration of the alkaline solution is 35 g / L. In S3, the fiber is viscose fiber; In S4, the cold stacking time is 22 hours and the cold stacking temperature is -5°C; the plastic film is low-density polyethylene film. In S5, the concentration of the alkaline solution is 5 g / L; In S5, the temperature in the water washing tank containing the alkaline solution is 78°C.

[0028] Example 3 A method for addressing the poor performance of cold-rolled modified fibers in winter includes the following steps: S1. Heat the modifier and alkaline solution to 60℃ respectively; S2. Add the modifier and alkaline solution to the dyeing tank at a weight ratio of 5:1, and mix and stir. S3. After the fiber is formed into a web, it is immersed in the dyeing tank. The liquid content of the fiber is controlled to be 160% by the rolling mill, and then it is wound up. S4. Wrap the wound fibers in plastic film, seal them, and store them in a cold stack. S5. After the cold-piled fibers are washed in a water washing tank containing an alkaline solution, they are then acid-washed and washed in hot water at a temperature of 50°C to obtain modified fibers. Among them, S1, S2, S3, S4 and S5 were all carried out at an ambient temperature of -5℃; In S1, the modifier is selected from polycaprolactone-hydroxyapatite composite solution; in S1 and S5, the alkaline solution is selected from one or more of sodium hydroxide and potassium hydroxide. In S2, the concentration of the alkaline solution is 40 g / L; In S3, the fiber is viscose fiber; In S4, the cold stacking time is 23 hours and the cold stacking temperature is -5°C; the plastic film is low-density polyethylene film. In S5, the concentration of the alkaline solution is 10 g / L; In S5, the temperature in the water washing tank containing the alkaline solution is 85℃.

[0029] Example 4 A method for addressing the poor performance of cold-rolled modified fibers in winter includes the following steps: S1. Heat the modifier and alkaline solution to 55℃ respectively; S2. Add the modifier and alkaline solution to the dyeing tank at a weight ratio of 4:1, and mix and stir. S3. After the fiber is formed into a web, it is immersed in the dyeing tank. The liquid content of the fiber is controlled to be 170% by the rolling mill, and then it is wound up. S4. Wrap the wound fibers in plastic film, seal them, and store them in a cold stack. S5. After the cold-piled fiber is washed in a water washing tank containing an alkaline solution, it is then acid-washed and washed in hot water at a temperature of 50°C to obtain the modified fiber. Among them, S1, S2, S3, S4 and S5 were all carried out at an ambient temperature of -5℃; In S1, the modifier is selected from polycaprolactone-hydroxyapatite composite solution; in S1 and S5, the alkaline solution is selected from sodium hydroxide; in S2, the concentration of the alkaline solution is 38 g / L. In S3, the fiber is viscose fiber; In S4, the cold stacking time is 24 hours and the cold stacking temperature is -5℃; the plastic film is low-density polyethylene film. In S5, the concentration of the alkaline solution is 8 g / L; In S5, the temperature in the water washing tank containing the alkaline solution is 90℃.

[0030] Comparative Example 1 Based on Example 2, except that in S2 the weight ratio of modifier to alkaline solution is 2:1, all other components and preparation methods are the same as in Example 2.

[0031] Comparative Example 2 Based on Example 2, except that in S2 the weight ratio of modifier to alkaline solution is 6:1, the other preparation methods are the same as in Example 2.

[0032] Comparative Example 3 Based on Example 2, except that the liquid carrying rate in S3 is 140%, the other preparation methods are the same as in Example 2.

[0033] Comparative Example 4 Based on Example 2, except that in S5, the alkaline solution in the washing tank is replaced with an equal amount of water, the rest of the preparation methods are the same as in Example 2.

[0034] The modified fibers prepared in Examples 1-4 and Comparative Examples 1-4 were subjected to performance testing, and the test results are shown in Table 1.

[0035] Table 1 As can be seen from Examples 1-4, Comparative Examples 1-4 and Table 1, the modified fibers prepared by the specific modified fiber method of this application exhibit excellent modification effects when subjected to fiber modification treatment in a low-temperature environment and cold stacking treatment in a low-temperature environment. The color fixation test shows high color fixation efficiency, and when used in color absorption sheets, the color absorption time is short, effectively solving the limitations of low-temperature fiber modification in winter.

[0036] Example 5 Based on Example 2, except that the modifier is cationic modifier GX680 (brand: Honghao), the preparation method is the same as in Example 2.

[0037] Example 6 Based on Example 2, except that an ionic liquid is added in S2, the rest of the preparation methods are the same as in Example 2; wherein, the weight of the ionic liquid is 35% of the weight of the modifier, and the ionic liquid is an alkyl imidazoline organosilicon quaternary ammonium salt solution.

[0038] Examples 7-9 Based on Example 2, except that the fiber is subjected to ultrasonic pretreatment in an ionic liquid before cold rolling, the rest of the preparation method is the same as in Example 2; wherein, the ionic liquid is an alkyl imidazoline organosilicon quaternary ammonium salt solution.

[0039] Example 7 The ultrasonic pretreatment process is as follows: ultrasonic frequency is 20kHz, ultrasonic time is 10min.

[0040] Example 8 The ultrasonic pretreatment process involves an ultrasonic frequency of 35 kHz and an ultrasonic time of 6 min.

[0041] Example 9 The ultrasonic pretreatment process is as follows: ultrasonic frequency is 50kHz, and ultrasonic time is 4min.

[0042] Example 10 Based on Example 8, except that an equal amount of polyphosphoric acid-ethanol mixed solution (the polyphosphoric acid-ethanol mixed solution is obtained by mixing polyphosphoric acid and ethanol in a weight ratio of 1:10) is used to replace the alkyl imidazoline organosilicon quaternary ammonium salt, the rest of the preparation method is the same as in Example 8.

[0043] The modified fibers prepared in Examples 5-10 were subjected to performance testing, and the test results are shown in Table 2.

[0044] Table 2 As can be seen from Examples 5 and 2 and Table 2, this application uses a specific modifier, which has excellent fiber modification effect. The polycaprolactone-hydroxyapatite composite solution has good wettability and polarity, which can effectively improve the wettability of the fiber surface and promote the adsorption and diffusion of dyes in the fiber. As can be seen from Examples 6-10, 2 and Table 2, this application also includes pre-treating the fibers in ultrasound, which can further optimize the modification effect of the fibers and improve dyeing performance and durability; and at the same time, the use of specific alkyl imidazoline organosilicon quaternary ammonium salts has good wettability and permeability, which can form a stable interface with the fiber surface, improve dyeing performance and durability, and effectively improve the modification effect in low temperature environment.

[0045] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the principles of this application should be covered within the scope of protection of this application.

Claims

1. A method for cold-rolling modified fibers, characterized in that, Includes the following steps: S1. Heat the modifier and alkaline solution to 40-60℃ respectively; S2. Take the modifier and alkaline solution and inject them into the dyeing tank at a weight ratio of 3-5:

1. Mix and stir, and perform ultrasound in the ionic liquid at a frequency of 20-50kHz for 4-10min. S3. After the fibers are formed into a web, they are immersed in a dyeing tank. The liquid content of the fibers is controlled to be 150-170% by a rolling mill, and then the web is wound up. S4. Wrap the wound fibers in plastic film, seal them, and store them in a cold stack. S5. After the cold-piled fiber is washed in a water washing tank containing an alkaline solution, it is then acid-washed and washed with hot water to obtain the modified fiber. The modifier is a polycaprolactone-hydroxyapatite composite solution; Preparation method of polycaprolactone-hydroxyapatite composite solution: dissolve polycaprolactone in ethanol, then add nano-hydroxyapatite and mix and stir to prepare polycaprolactone-hydroxyapatite composite solution, wherein the weight ratio of polycaprolactone, nano-hydroxyapatite and ethanol is 1:0.5:

2. In S4, the cold reactor time is 20-24 hours; In step S5, the concentration of the alkaline solution is 2-10 g / L; In step S5, the temperature in the water washing tank containing the alkaline solution is 60-90℃.

2. The method for cold-rolled modified fibers according to claim 1, characterized in that, In S1 and S5, the base is selected from one or more of sodium hydroxide and potassium hydroxide.

3. The method for cold-rolled modified fibers according to claim 1, characterized in that, In S1, the concentration of the alkaline solution is 30-40 g / L.

4. The method for cold-rolled modified fibers according to claim 1, characterized in that, The ionic liquid is an alkyl imidazoline organosilicon quaternary ammonium salt solution.

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