Low-temperature dyeing processing method of hydrophilic modified polyester fiber
Through the surface etching and hydrophilic modification of polyester fibers through low-temperature dyeing technology, the problems of poor dyeing and insufficient hydrophilicity of polyester fibers are solved, and efficient dyeing at low temperatures is achieved, energy consumption and pollution are reduced, and process flow is simplified.
Patent Information
- Application Number
- CN202510822332.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-19
- Publication Date
- 2025-08-15
AI Technical Summary
Polyester fibers have poor dyeing properties and insufficient hydrophilicity. The traditional dyeing process is cumbersome, high cost, high pollution, and damage the mechanical properties of the fiber under high temperature and high pressure conditions.
The polyester fiber is surface etched by a low eutectic solvent, and the hydrophilic modified polyester fiber is prepared by treating the hydrogen bond donor/hydrogen bond acceptor system, and dyed under low temperature conditions. The hydrophilic modification and low temperature dye of the polyester fiber are achieved using homemade liquid dispersed dyes and reducing cleaning agents.
Without damaging the structure and mechanical properties of polyester fibers, it improves its hydrophilicity and dyeing properties, achieves low-temperature dyeing, reduces energy consumption and pollution, simplifies process flow, and reduces costs.
Smart Images
Figure CN120486128A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical fields of fiber surface reconstruction and low-temperature dyeing, and in particular to a low-temperature dyeing processing method for hydrophilic modified polyester fibers. Background Art
[0002] Polyester fiber, also known as polyester, is a synthetic fiber with high crystallinity. It can be spun using conventional processing techniques, requiring no specialized equipment or techniques. It exhibits high strength, good abrasion resistance, excellent elasticity, and resistance to chemical, heat, and chemical corrosion. The resulting yarn and fabric possess excellent hand feel and drape. It has broad application prospects in various industries, including clothing, home textiles, and footwear. It is also widely used in automotive and industrial applications.
[0003] Low-temperature dyeing technology currently offers numerous advantages over traditional dyeing. Typically performed at lower temperatures, low-temperature dyeing reduces dye usage and the emission of hazardous substances, lowering production costs while also reducing environmental pollution. Dyeing at low temperatures reduces damage to fibers caused by high temperatures, preserving their mechanical properties. Furthermore, low-temperature dyeing improves dye substantivity and color fixation, enhancing product quality, and further increasing equipment utilization and production efficiency, resulting in substantial economic benefits for businesses.
[0004] However, polyester fibers have two significant drawbacks: First, they have poor dyeability. The lack of specific dyeing groups on the chains and their low polarity make dyeing difficult and difficult, preventing dye molecules from easily entering the fibers. Second, they have poor hydrophilicity, lacking water absorption and water affinity, and lacking comfort. Polyester fiber's tightly packed macromolecular chains, high crystallinity and orientation, low polarity, and lack of hydrophilic groups make traditional dyeing and post-processing processes cumbersome and inefficient. Dyeing requires high temperatures and pressures, and the use of numerous chemical additives creates significant environmental pollution and produces less vibrant colors.
[0005] Deep eutectic solvents (DES), analogs of ionic liquids, are non-polluting, biodegradable, and easily prepared high-efficiency solvents. The research aims to modify polyester using DES to etch and reconstruct its surface without damaging its internal structure and mechanical properties, resulting in highly hydrophilic and biocompatible polyester materials. Furthermore, the modified polyester can be dyed at low temperatures and atmospheric pressure, achieving dyeing efficiencies comparable to those achieved at high temperatures and high pressures.
[0006] In summary, the existing technology for improving the cell affinity of the surface of polyester tissue engineering materials has bottlenecks such as complex processes, unsatisfactory results, high costs under high temperature and high pressure dyeing conditions, and high pollution, which need to be solved urgently. Summary of the Invention
[0007] The present invention aims to solve the technical problems existing in the prior art. To this end, the present invention provides a low-temperature dyeing method for hydrophilically modified polyester fibers. The purpose of the present invention is to improve the hydrophilicity of the polyester fibers, modify the polyester fibers, and simultaneously achieve the characteristics of low-temperature dyeing. The method has the advantages of being gentle, pollution-free, biodegradable, and low-cost.
[0008] Based on the above purpose, the present invention provides a hydrophilic polyester fiber and a low-temperature dyeing process, wherein the processing process is to sequentially wash the polyester fiber with water, treat it with a hydrogen bond donor / hydrogen bond acceptor system, wash it with water, and dry it to obtain a hydrophilic polyester fiber. Then, a dye mixture is prepared, which is a laboratory-made liquid disperse dye, including a mixture of dye, dispersant, water with a pH of 5, etc. Then, it is dyed in an infrared dyeing machine, and then reduced and cleaned and dried. Furthermore, a low-temperature dyeing processing method for hydrophilic modified polyester fiber includes the following steps: (1) mixing a hydrogen bond acceptor and a hydrogen bond donor, stirring and dissolving them at high temperature until they are transparent, and then stirring and keeping them warm to obtain a low eutectic solvent; (2) placing the polyester fiber in the low eutectic solvent, adding sodium hydroxide, and heating to obtain a hydrophilic modified polyester fiber; (3) preparing a dye mixture with a liquid disperse dye, then adding the dye mixture and the hydrophilic modified polyester fiber to a dyeing machine, dyeing them in the dyeing machine at low temperature, reducing and cleaning, and drying to obtain a finished polyester fiber.
[0009] Preferably, in step (1), the hydrogen bond acceptor is choline chloride; the hydrogen bond donor is one or more of oxalic acid, urea, and ethylene glycol. Furthermore, the hydrogen bond donor is ethylene glycol, the hydrogen bond acceptor is choline chloride, and the molar ratio of the hydrogen bond acceptor / hydrogen bond donor system is 1:1.75-2.5.
[0010] Preferably, in step (1), the high temperature is 60-140°C, and the stirring time is 1-4 hours. Furthermore, the reaction temperature is 80-100°C, and the reaction time is 2-3.5 hours.
[0011] Preferably, in step (2), the mass ratio of the added sodium hydroxide to the deep eutectic solvent is 0.25-3.75:100. The mass ratio of the polyester fiber to the deep eutectic solvent is 1:30-60. Furthermore, the mass fraction of the sodium hydroxide added to the hydrogen bond donor / hydrogen bond acceptor system is 0.25%-2.25%, and the mass ratio of the polyester fiber to the hydrogen bond donor / hydrogen bond acceptor system is 1:40-60.
[0012] Preferably, in step (2), the heating treatment is performed at 60-150° C. for 2-20 min. Furthermore, the hydrogen bond donor / hydrogen bond acceptor system is treated at a temperature of 80-120° C. for 2-10 min.
[0013] Preferably, in step (3), the dyeing temperature curve of the dyeing machine is to increase the temperature to 90-130°C at a rate of 1-3°C / min under ambient temperature conditions, maintain at this temperature for 45-75 minutes, and then cool down to ambient temperature at a rate of 1-3°C / min. Furthermore, the dyeing temperature curve is to increase the temperature to 110-120°C at a rate of 2°C / min under room temperature conditions, maintain at this temperature for 60 minutes, and then cool down to room temperature at a rate of 2°C / min.
[0014] Preferably, in step (3), a liquid disperse dye is added to an acetic acid aqueous solution to prepare a dye mixture, wherein the pH of the acetic acid aqueous solution is 4-6; and the mass ratio of the liquid disperse dye to the hydrophilically modified polyester fiber is 0.5-2:100. Furthermore, the required amount of the dye is 2-3% (based on the weight of the fabric), and the water with a pH of 5 is prepared by mixing glacial acetic acid and water.
[0015] Preferably, in step (3), the reduction cleaning is performed using a reduction cleaning agent, wherein the reduction cleaning agent comprises sodium hydroxide, sodium dithionite, and water, wherein the concentration of sodium hydroxide in the reduction cleaning agent is 1 to 3 g / L; the concentration of sodium dithionite in the reduction cleaning agent is 1 to 3 g / L; and the bath ratio of the hydrophilic modified polyester fiber to the reduction cleaning agent is 0.5 to 2 g:100 mL. Furthermore, the reduction cleaning agent is composed of 2 g / L sodium hydroxide and 2 g / L sodium dithionite, and the bath ratio is 1:100.
[0016] The present invention also provides application of the processing technology of the hydrophilic polyester fiber in the hydrophilic modification and low-temperature modification of polyester chemical fibers.
[0017] Beneficial effects of the present invention:
[0018] 1. The present invention acts on the molecular chain segments activated on the surface of polyester under low temperature conditions without changing the aggregated structure of polyester and affecting its mechanical properties, embedding them into the surface to achieve surface reconstruction and complete the modification of polyester by DES. The process is simple and controllable.
[0019] 2. The present invention can functionally modify polyester fibers, completing their transformation from hydrophobic to hydrophilic, and effectively improving their dyeing properties.
[0020] 3. The modified polyester fiber obtained by the present invention can be dyed at low temperature, eliminating high temperature and high pressure conditions, maintaining a high dye uptake rate, optimizing the process, and improving the dyeing effect.
[0021] 4. The processing technology of the present invention has the advantages of being mild, pollution-free, low-cost, recycling and energy-saving, and the process is controllable, non-toxic and pollution-free. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 : SEM diagram of modified hydrophilic polyester fiber.
[0023] Figure 2 : Stress-strain curves of modified hydrophilic polyester fiber.
[0024] Figure 3 : Schematic diagram of water contact angle of modified hydrophilic polyester fiber and original polyester fiber.
[0025] Figure 4 : Digital images of modified hydrophilic polyester fibers dyed with disperse dyes at 110, 120, and 130°C.
[0026] Figure 5 : K / S curve of modified hydrophilic polyester fiber.
[0027] Figure 6 : K / S histogram of modified hydrophilic polyester fiber. DETAILED DESCRIPTION
[0028] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.
[0029] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should have the common meanings understood by persons having ordinary skills in the field to which the present disclosure belongs.
[0030] In the present invention, the best hydrogen bond donor / hydrogen bond acceptor is the choline chloride / ethylene glycol system, and its preparation and action on polyester are as follows:
[0031] Choline chloride, ethylene glycol (both analytically pure, purchased from Shanghai MacLean Biochemical Technology Co., Ltd.)
[0032] Preparation of (Choline chloride / ethylene glycol) deep eutectic solvent: Mix at a molar ratio of 1:1.75-2.5, place choline chloride first and then ethylene glycol into a conical flask in that order, add a magnetic rotor, and place on a constant temperature magnetic stirrer in an oil bath at 80-100°C. Stir and dissolve until transparent, then continue stirring for 2-3.5 hours before removing and setting aside.
[0033] Treatment of polyester fibers and fabrics with (choline chloride / ethylene glycol) low eutectic solvent: The polyester fiber is pre-washed with ultrapure water for 20-30 minutes and dried in an oven at 60-70 degrees. Take part of the low eutectic solvent and add 0.25%-2.25% sodium hydroxide at 80-120°C. Then, the polyester is immersed in the pre-prepared choline chloride / ethylene glycol system (the mass ratio of polyester fiber to the system is 1:40-60), treated at 80-120°C for 2-10 minutes, then taken out, repeatedly washed with ultrapure water for 20-30 minutes, and dried in an oven at 60-70 degrees for testing.
[0034] The following is an explanation through specific examples:
[0035] Example 1
[0036] Preparation of (Choline chloride / ethylene glycol) deep eutectic solvent: Accurately weigh choline chloride and ethylene glycol at a molar ratio of 1:1.75 and place them into a conical flask in the order of choline chloride first and then ethylene glycol. Add a magnetic rotor and place on a constant temperature magnetic stirrer in an oil bath at 80°C. Stir and dissolve until transparent. Continue stirring for 2 hours and remove from the flask for later use.
[0037] Treatment of polyester fibers and fabrics with (choline chloride / ethylene glycol) low eutectic solvent: The polyester fibers were pre-washed with ultrapure water for 20 minutes and dried in an oven at 60°C. Part of the low eutectic solvent was taken and 0.25% sodium hydroxide was added at 80°C (i.e., the mass ratio of added sodium hydroxide to the low eutectic solvent was 0.25:100). The fibers were then immersed in the pre-prepared choline chloride / ethylene glycol system (the mass ratio of polyester fibers to the low eutectic solvent was 1:40), treated at 80°C for 2 minutes, taken out, repeatedly washed with ultrapure water for 20 minutes, and dried in an oven at 60 degrees for later use. Samples were retained for testing.
[0038] Example 2
[0039] Preparation of (Choline chloride / ethylene glycol) deep eutectic solvent: Accurately weigh choline chloride and ethylene glycol in a molar ratio of 1:2, and place them into a conical flask in the order of choline chloride first and then ethylene glycol. Add a magnetic rotor and place on a constant temperature magnetic stirrer in an oil bath. Stir and dissolve at 90°C until transparent. Continue stirring for 2.5 hours and remove from the flask for later use.
[0040] Treatment of polyester fibers and fabrics with (choline chloride / ethylene glycol) low eutectic solvent: The polyester fibers were pre-washed with ultrapure water for 25 minutes and dried in a 60-degree oven for later use. Part of the low eutectic solvent was taken and 1.25% sodium hydroxide was added at 100°C (i.e., the mass ratio of added sodium hydroxide to the low eutectic solvent was 1.25:100). The fibers were then immersed in the pre-prepared choline chloride / ethylene glycol system (the mass ratio of polyester fiber to the system was 1:50), treated at 100°C for 6 minutes, taken out, repeatedly washed with ultrapure water for 25 minutes, and dried in a 60-degree oven for later use. Samples were retained for testing.
[0041] Example 3
[0042] Preparation of (Choline chloride / ethylene glycol) deep eutectic solvent: Accurately weigh choline chloride and ethylene glycol at a molar ratio of 1:2.5 and place them into a conical flask in the order of choline chloride and then ethylene glycol. Add a magnetic rotor and place the mixture on a constant temperature magnetic stirrer in an oil bath at 100°C. Stir and dissolve until transparent. Continue stirring for 3 hours and remove from the flask for later use.
[0043] Treatment of polyester fibers and fabrics with (choline chloride / ethylene glycol) low eutectic solvent: The polyester fiber was pre-washed with ultrapure water for 30 minutes and dried in a 60-degree oven for later use. Part of the low eutectic solvent was taken and 2.25% sodium hydroxide was added at 120°C (i.e., the mass ratio of added sodium hydroxide to the low eutectic solvent was 2.25:100). The fiber was then immersed in the pre-prepared choline chloride / ethylene glycol system (the mass ratio of polyester fiber to the system was 1:50), treated at 120°C for 10 minutes, then taken out, repeatedly washed with ultrapure water for 30 minutes, and dried in a 60-degree oven for later use. A sample was retained for testing.
[0044] In the present invention, the operation process of low temperature dyeing is:
[0045] Weigh 1g of modified hydrophilic polyester fiber, which requires 2-3% dye (based on fabric weight). The required amount of liquid dye is calculated using the solid content. An appropriate amount of water (pH 5) is added at a bath-to-cloth ratio of 50:1, and the fiber is then placed in an infrared dyeing machine. The dyeing temperature profile is to increase the temperature from room temperature to 110-120°C at a rate of 2°C / min, maintain this temperature for 60 minutes, and then cool back to room temperature at a rate of 2°C / min. Afterwards, the fiber is rinsed with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100. After rinsing, the fiber is dried at 60°C before testing.
[0046] The following is an explanation through specific examples:
[0047] Application Example 1
[0048] Weighing 1g of modified hydrophilic polyester fiber requires 2% (based on fabric weight) of liquid disperse dye (0.02g of commercial Disperse Orange 30, Hangzhou Xinkang Pharmaceutical Chemical Co., Ltd.). The required amount of liquid dye is calculated using the solid content. An appropriate amount of pH 5 acetic acid aqueous solution is added to the dye mixture at a 50:1 bath-to-cloth ratio (i.e., the mass ratio of dye mixture to modified hydrophilic polyester fiber is 50g:1g). The resulting mixture is then placed in an infrared dyeing machine. The dyeing temperature profile is: heating at room temperature to 110°C at a rate of 2°C / min, maintaining this temperature for 60 minutes, and then cooling to room temperature at a rate of 2°C / min. The fabric is then rinsed with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100 (i.e., the modified hydrophilic polyester fiber to reducing detergent ratio is 1g:100g). After rinsing, the fabric is dried at 60°C before testing.
[0049] Application Example 2
[0050] Weigh 1g of modified hydrophilic polyester fiber and add 2% (based on fabric weight) of dye (commercial liquid Disperse Blue 79, Jiangsu Yabang Dye Co., Ltd., 0.02g). The required amount of liquid dye is calculated using the solid content. An appropriate amount of pH 5 acetic acid solution is added at a bath-to-cloth ratio of 50:1, and then placed in an infrared dyeing machine. The dyeing temperature profile is to increase the temperature to 120°C at room temperature at a rate of 2°C / min, maintain this temperature for 60 minutes, and then cool to room temperature at a rate of 2°C / min. Afterwards, the fiber is cleaned with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100 (i.e., the ratio of modified hydrophilic polyester fiber to reducing detergent is 1g:100g). After cleaning, the fiber is dried at 60°C and tested.
[0051] Application Example 3
[0052] Weigh 1g of modified hydrophilic polyester fiber and add 3% (based on fabric weight) of dye (commercial Disperse Orange 30, Hangzhou Xinkang Pharmaceutical Chemical Co., Ltd., 0.03g). The required amount of liquid dye is calculated using the solid content. An appropriate amount of pH 5 acetic acid solution is added at a bath-to-cloth ratio of 50:1, and then placed in an infrared dyeing machine. The dyeing temperature profile is to increase the temperature to 110°C at room temperature at a rate of 2°C / min, maintain this temperature for 60 minutes, and then cool to room temperature at a rate of 2°C / min. Afterwards, the fiber is cleaned with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100 (i.e., the modified hydrophilic polyester fiber to reducing detergent ratio is 1g:100g). After cleaning, the fiber is dried at 60°C and tested.
[0053] Application Example 4
[0054] Weigh 1g of modified hydrophilic polyester fiber and add 3% (based on fabric weight) of dye (commercial liquid Disperse Blue 79, Jiangsu Yabang Dye Co., Ltd., 0.02g). The required amount of liquid dye is calculated using the solid content. An appropriate amount of pH 5 acetic acid solution is added at a bath-to-cloth ratio of 50:1, and then placed in an infrared dyeing machine. The dyeing temperature profile is to increase the temperature to 120°C at room temperature at a rate of 2°C / min, maintain this temperature for 60 minutes, and then cool to room temperature at a rate of 2°C / min. Afterwards, the fiber is cleaned with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100 (i.e., the ratio of modified hydrophilic polyester fiber to reducing detergent is 1g:100g). After cleaning, the fiber is dried at 60°C and tested.
[0055] Comparative Example 1
[0056] Weigh 1g of raw polyester fiber and add 3% (based on fabric weight) dye. The required amount of liquid dye is calculated using the solid content. An appropriate amount of water with a pH of 5 is added at a bath-to-cloth ratio of 50:1, and the fiber is then placed in an infrared dyeing machine. The dyeing temperature profile is to increase the temperature from room temperature to 110°C at a rate of 2°C / min, maintain this temperature for 60 minutes, and then cool it back to room temperature at a rate of 2°C / min. Afterwards, the fiber is cleaned with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100. After cleaning, the fiber is dried at 60°C and tested.
[0057] Comparative Example 2
[0058] Weigh 1g of raw polyester fiber and 3% (based on fabric weight) of dye are required. The required amount of liquid dye is calculated using the solid content. An appropriate amount of water with a pH of 5 is added at a bath-to-cloth ratio of 50:1, and the fiber is then placed in an infrared dyeing machine. The dyeing temperature profile is to increase the temperature from room temperature to 130°C at a rate of 2°C / min, maintain this temperature for 60 minutes, and then cool to room temperature at a rate of 2°C / min. Afterwards, the fiber is cleaned with a reducing detergent consisting of 2g / L sodium hydroxide and 2g / L sodium dithionite at a bath ratio of 1:100. After cleaning, the fiber is dried at 60°C and tested.
[0059] Surface micromorphology test of treated polyester fibers:
[0060] From the SEM of the original polyester fiber, we can see that Figure 1As shown in Figures ad, it can be clearly observed that the surface structure of the original polyester fiber (Figures a and b) is dense and smooth, lacking obvious rough features, and no swelling, thinning, broken fibers, or fiber splitting occurs, indicating that the fiber is not damaged or slightly damaged. However, the surface of the fiber treated with DES (Figures c and d) shows obvious etching features, accompanied by cracks, particle accumulation, and multi-level pore structures. This change in morphology indicates that DES has a strong etching ability on the polyester surface, which can destroy the original molecular chain arrangement and induce local swelling or dissolution, thereby forming a multi-level structure. This structural change not only helps to significantly increase the specific surface area of the material, but also provides more active sites for subsequent interface modification.
[0061] Polyester fiber mechanical properties test:
[0062] The electronic strength meter was used to compare the breaking strength of polyester fibers treated with different alkali concentrations. The results are as follows: Figure 2 As shown in the figure, the stress-strain curves show that the original polyester fabric has high tensile strength and good ductility, while the samples treated with DES show varying degrees of mechanical property degradation under different treatment conditions. Example 2 maintains good mechanical properties, indicating that the treatment conditions impart functionality to the polyester fabric surface while maintaining the integrity of the fiber structure. In contrast, the treatment intensity in Example 3 is too high, resulting in damage to the fiber structure and a significant deterioration in mechanical properties.
[0063] Hydrophilicity test of polyester fabric:
[0064] The static and dynamic contact angles of polyester fabrics were tested using a video contact angle tensiometer. Figure 3 As shown, the contact angle of a water droplet on the original polyester fabric surface remained at 130.6°, indicating strong hydrophobicity. However, after DES treatment, the contact angle rapidly dropped from 127.3° to 0°, achieving complete spreading in just 2 seconds, demonstrating superhydrophilic behavior. This phenomenon suggests that DES etching not only effectively alters the surface microstructure but also may introduce polar functional groups, significantly improving the wettability of the polyester surface.
[0065] Dyeing performance test of polyester fabric:
[0066] like Figure 4 As shown in the figure, it is obvious that the modified PET has a significant improvement in color depth compared to the original PET at different dyeing temperatures, whether dyed with Disperse Orange 30 or Disperse Blue 79. In contrast, DES-PET can achieve a color depth at 110 or 120°C similar to that achieved by PET at 130°C.
[0067] In order to further analyze the dyeing performance of polyester before and after surface reconstruction, the K / S value was used to quantify the dyeing depth. Figure 5 and Figure 6 As shown, the K / S value of DES-PET dyed orange at 120°C is similar to that of original PET dyed orange at 130°C, while the K / S value of DES-PET dyed blue at 120°C is much higher than that of original PET dyed blue at 130°C. Furthermore, the K / S value of DES-PET dyed at 120°C is much higher than that of DES-PLA dyed at other temperatures. This indicates that the K / S value is proportional to the dyeing temperature within a certain range. Untreated polyester fabric achieves an ideal dyeing depth only at a higher temperature (130°C), while DES-treated polyester samples achieve significantly higher K / S values at lower temperatures (110°C and 120°C), indicating that the improved surface structure and wettability effectively promote the adsorption and penetration of dye molecules. Surface DES (deep eutectic solvent) treatment offers significant advantages in achieving efficient low-temperature dyeing of polyester, significantly improving the K / S value of fabric dyeing with lower energy consumption.
[0068] Table 1 shows the color parameters of the modified hydrophilic polyester fiber. It can be clearly seen that the K / S value increases with the increase of temperature, showing a positive relationship. The K / S value of DES-PET is higher than that of the original PET at the same temperature. Moreover, the K / S value of DES-PET dyed with two different dyes at 120℃ is higher than that of the original PET dyed at 130℃. Figure 4 , Figure 5 , Figure 6 Correspondingly, it shows that it has completed effective modification and achieved the dyeing advantages of low temperature and low energy consumption. Table 1
Claims
1. A low-temperature dyeing method for hydrophilic modified polyester fiber, characterized in that: The following steps are involved: (1) mixing a hydrogen bond acceptor and a hydrogen bond donor, stirring and dissolving them at high temperature until they become transparent, and then stirring at this temperature to obtain a deep eutectic solvent; (2) placing the polyester fiber in a low eutectic solvent, adding sodium hydroxide, and heating to obtain a hydrophilically modified polyester fiber; (3) preparing a dye mixture from a liquid disperse dye, then adding the dye mixture and the hydrophilic modified polyester fiber into a dyeing machine, dyeing the dyeing machine at a low temperature, reduction cleaning, and drying to obtain a finished polyester fiber.
2. The low-temperature dyeing method for hydrophilic modified polyester fiber according to claim 1, characterized in that: In step (1), the hydrogen bond acceptor is choline chloride; The hydrogen bond donor is one or more of oxalic acid, urea, and ethylene glycol.
3. The low-temperature dyeing method for hydrophilically modified polyester fibers according to claim 1, characterized in that: In step (1), the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:0.75-2.
5.
4. The low-temperature dyeing method for hydrophilic modified polyester fiber according to claim 1, characterized in that: In step (1), the high temperature is 60-140° C., and the time of heat preservation and stirring is 1-4 hours.
5. The low-temperature dyeing method for hydrophilic modified polyester fiber according to claim 1, characterized in that: In step (2), the mass ratio of the added sodium hydroxide to the low eutectic solvent is 0.25-3.75:
100.
6. The low-temperature dyeing method for hydrophilically modified polyester fibers according to claim 1, characterized in that: In step (2), the heating treatment condition is: 60-150° C. for 2-20 min.
7. The low-temperature dyeing method for hydrophilically modified polyester fibers according to claim 1, characterized in that: In step (2), the mass ratio of the polyester fiber to the low eutectic solvent is 1:30-60.
8. The low-temperature dyeing method for hydrophilically modified polyester fibers according to claim 1, characterized in that: In step (3), the dyeing temperature curve of the dyeing machine is to heat up to 90-130°C at a rate of 1-3°C / min under ambient temperature conditions, maintain at this temperature for 45-75 minutes, and then cool down to ambient temperature at a rate of 1-3°C / min.
9. The low-temperature dyeing method for hydrophilically modified polyester fibers according to claim 1, characterized in that: In step (3), the reduction cleaning adopts a reduction cleaning agent, wherein the reduction cleaning agent adopts sodium hydroxide, sodium dithionite and water, and the concentration of sodium hydroxide in the reduction cleaning agent is 1-3 g / L; the concentration of sodium dithionite in the reduction cleaning agent is 1-3 g / L; The bath ratio of the hydrophilic modified polyester fiber to the reducing cleaning agent is 0.5-2g:100mL.
10. The low-temperature dyeing method for hydrophilically modified polyester fibers according to claim 1, characterized in that: In step (3), liquid disperse dye is added to acetic acid aqueous solution to prepare a dye mixture, wherein the pH of the acetic acid aqueous solution is 4 to 6; The mass ratio of the liquid disperse dye to the hydrophilic modified polyester fiber is 0.5-2:100.