Colored tpu elastomeric fiber material and method of making same
By introducing tertiary amine group modifiers and phosphorus-nitrogen synergistic flame retardant system into TPU fibers, the problems of insufficient dyeing and flame retardant properties of TPU fibers are solved, achieving efficient dyeing and flame retardant effects while maintaining good mechanical properties.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGZHOU XINZHANJIANG SPECIAL FIBER
- Filing Date
- 2025-09-10
- Publication Date
- 2026-06-19
AI Technical Summary
Traditional TPU fibers have shortcomings in dyeing and flame retardant properties, making it difficult to obtain bright and durable colors through conventional methods, and their mechanical properties are compromised, limiting their application in fields with high safety requirements.
By introducing modifiers containing tertiary amine groups, the microstructure of the fiber is improved, and a phosphorus-nitrogen synergistic flame retardant system is introduced, providing more dye binding sites and enhancing the flame retardant properties of the fiber.
It significantly improves the dyeing and flame retardant properties of fibers while maintaining good mechanical properties, achieving improved dyeing rate and uniformity, increased limiting oxygen index, and significant flame retardant effect.
Smart Images
Figure IMAGE_7BFDDCD2-63D3-4598-A9C5-BA21E52721CF
Abstract
Description
Technical Field
[0001] This invention belongs to the field of fiber technology, specifically relating to a colored TPU elastic fiber material and its preparation method. Background Technology
[0002] Currently, TPU elastic fibers are widely used in textiles, clothing, and medical fields due to their excellent elasticity, abrasion resistance, and fatigue resistance. However, traditional TPU fibers have significant shortcomings in dyeing. Because their molecular chains lack sufficient polar groups and dye binding sites, these fibers are difficult to dye with bright, long-lasting colors using conventional dyeing processes, especially exhibiting poor adsorption capacity for acidic dyes. Existing technologies typically improve dyeing performance by introducing small amounts of cationic monomers or performing surface treatments on the fibers; however, these methods provide limited dye binding sites and often sacrifice the material's mechanical properties. Furthermore, conventional TPU materials have a low limiting oxygen index and poor flame retardant properties, which limits their application in certain fields with high safety requirements.
[0003] Therefore, developing a colored TPU elastic fiber material that combines excellent dyeing properties, good mechanical properties, and flame retardant properties has become a technical problem that urgently needs to be solved in this field. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a colored TPU elastic fiber material and its preparation method.
[0005] The objective of this invention can be achieved through the following technical solutions:
[0006] A method for preparing a colored TPU elastic fiber material includes the following steps:
[0007] Step 1: Under a protective atmosphere, polytetramethylene ether glycol and diphenylmethane-4,4'-diisocyanate are mixed, the temperature is raised to 80°C, and the reaction is carried out for 2-3 hours. Then, the mixture is cooled to 30°C, N,N-dimethylacetamide is added, followed by the dropwise addition of ethylenediamine solution. The mixture is stirred for another 2-3 hours to obtain the spinning solution.
[0008] Step 2: Add the modifier to N,N-dimethylacetamide and stir until homogeneous to obtain a modifier solution; mix the modifier solution with the spinning solution and stir continuously. After vacuum degassing, spin to obtain TPU elastic fiber material.
[0009] In a more optimized manner, the raw materials for preparing the spinning solution include the following components: by weight, 40-50 parts of polytetramethylene ether glycol, 8-10 parts of diphenylmethane-4,4'-diisocyanate, 80-100 parts of N,N-dimethylacetamide, and 13-14 parts of ethylenediamine solution; wherein the concentration of the ethylenediamine solution is 23 wt%.
[0010] Ideally, the concentration of the modifier solution is 35 wt%.
[0011] Ideally, the mass ratio of the modifier solution to the spinning solution is 1-3:100.
[0012] A more optimized method for preparing the modifier is as follows: Under a protective atmosphere, the modifier monomer is added to N,N-dimethylacetamide and stirred evenly at 70°C. Then, bismuth neodecanoate is added and stirred evenly again. Subsequently, a dicyclohexylmethane-4,4'-diisocyanate solution is added dropwise to the above system, and the reaction is continued to be stirred at 70°C for 1-2 hours. After the reaction is completed, water is added to the system, and then the system is dried under vacuum at 40°C to obtain the modifier.
[0013] More preferably, the raw materials for preparing the modifier include the following components: by weight, 10-12 parts of the modifying monomer, 50-60 parts of N,N-dimethylacetamide, 1-2 parts of bismuth neodecanoate, and 18-20 parts of dicyclohexylmethane-4,4'-diisocyanate solution; wherein the concentration of the dicyclohexylmethane-4,4'-diisocyanate solution is 25 wt%.
[0014] In a more optimized manner, the preparation process of the modified monomer is as follows:
[0015] S1: Mix p-hydroxybenzaldehyde, N-aminoethylpiperazine and isopropanol, raise the temperature to 75°C, stir and react for 6-8 hours. After the reaction is complete, remove isopropanol by rotary evaporation to obtain intermediate A.
[0016] S2: Under a protective atmosphere, intermediate A is added to tetrahydrofuran, cooled to 0-5℃, and a tetrahydrofuran solution of methyl dichlorophosphate is slowly added dropwise. After the addition is complete, the temperature is raised to 65℃, and the reaction is carried out for 6-8 hours. The mixture is then cooled to room temperature, filtered, washed, and dried to obtain the modified monomer.
[0017] In the proposed method, the aldehyde group of p-hydroxybenzaldehyde first undergoes a nucleophilic addition-elimination reaction with the primary amino group of N-aminoethylpiperazine in isopropanol solvent, generating intermediate A containing an imine bond and a phenolic hydroxyl group. Then, under a protective atmosphere, the secondary amino group on the piperazine ring of intermediate A nucleophilically attacks the phosphorus atom, eliminating hydrogen chloride and forming a phosphorus-nitrogen bond, thereby preparing the modified monomer. The structure of the modified monomer is shown below:
[0018]
[0019] In a more optimized manner, the raw materials for preparing intermediate A include the following components: by weight, 10-12 parts of p-hydroxybenzaldehyde, 9-10 parts of N-aminoethylpiperazine, and 80-100 parts of isopropanol.
[0020] More preferably, the raw materials for preparing the modified monomer include the following components: by weight, 10-12 parts of intermediate A, 50-80 parts of tetrahydrofuran, and 12-18 parts of a tetrahydrofuran solution of methyl dichlorophosphate; the concentration of the tetrahydrofuran solution of methyl dichlorophosphate is 25 wt%.
[0021] The beneficial effects of this invention are:
[0022] Firstly, traditional polyurethane fibers rely solely on the protonation of a limited number of urethane groups in the molecular chain under acidic conditions to provide cationic sites. These sites are few in number, and due to the high crystallinity and orderly arrangement of their hard segments, dye molecules have difficulty penetrating and binding to them. Therefore, physical adsorption mainly relies on van der Waals forces, resulting in low and weak adsorption. This invention introduces a copolymer (modifier) containing tertiary amine groups. These tertiary amine groups are more easily protonated under acidic conditions, forming positively charged quaternary ammonium salt groups. These groups provide specific sites for binding to acidic dye anions.
[0023] Secondly, the large-volume spatial structure of the modifier disrupts the regular arrangement and hydrogen bond network between the hard segments in the original polyurethane molecule, reducing the crystallinity of the hard and soft segments; making the microstructure of the fiber more loose and disordered, providing more and smoother diffusion channels for dye molecules, enabling them to penetrate into the fiber more easily, and improving the dyeing rate and uniformity.
[0024] Thirdly, the phosphorus-nitrogen synergistic flame retardant system introduced into the modified monomer structure can promote the formation of a dense and stable carbonized layer on the surface of the fiber material during combustion, effectively isolating heat and oxygen from being transferred inward. At the same time, the piperazine ring structure decomposes upon heating to produce non-combustible gas, diluting the concentration of combustibles and further inhibiting the combustion process. This significantly improves the limiting oxygen index (LOI) of the material, reduces the heat release rate, and gives the fiber a long-lasting flame retardant effect. Detailed Implementation
[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0026] Example 1: A method for preparing a colored TPU elastic fiber material, comprising the following steps:
[0027] Step 1: Under a protective atmosphere, 40 parts of polytetramethylene ether glycol and 8 parts of diphenylmethane-4,4'-diisocyanate were mixed, the temperature was raised to 80°C, and the reaction was carried out for 2 hours. Then the mixture was cooled to 30°C, 80 parts of N,N-dimethylacetamide were added, and 13 parts of ethylenediamine solution (concentration of 23wt%) were added dropwise. The mixture was stirred for another 2 hours to obtain the spinning solution.
[0028] Step 2: Add the modifier to N,N-dimethylacetamide and stir until homogeneous to obtain a modifier solution (concentration 35wt%); mix the modifier solution with the spinning solution and stir continuously. After vacuum degassing, spin to obtain TPU elastic fiber material; wherein, the mass ratio of the modifier solution to the spinning solution is 1:100.
[0029] The modifier is prepared as follows: Under a protective atmosphere, 10 parts of the modifier monomer are added to 50 parts of N,N-dimethylacetamide and stirred evenly at 70°C. Then, 1 part of bismuth neodecanoate is added and stirred evenly again. After that, 18 parts of dicyclohexylmethane-4,4'-diisocyanate solution (concentration of 25wt%) are added dropwise to the above system and stirred at 70°C for 1 hour. After the reaction is completed, water is added to the system and then vacuum dried at 40°C to obtain the modifier.
[0030] The preparation process of the modified monomer is as follows:
[0031] S1: Mix 10 parts of p-hydroxybenzaldehyde, 9 parts of N-aminoethylpiperazine, and 80 parts of isopropanol, raise the temperature to 75°C, stir and react for 6 hours. After the reaction is complete, remove the isopropanol by rotary evaporation to obtain intermediate A.
[0032] S2: Under a protective atmosphere, 10 parts of intermediate A were added to 50 parts of tetrahydrofuran, cooled to 0°C, and 12 parts of a tetrahydrofuran solution of methyl dichlorophosphate (concentration 25wt%) were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C, and the reaction was carried out for 6 hours. The mixture was then cooled to room temperature, filtered, washed, and dried to obtain the modified monomer.
[0033] Example 2: A method for preparing a colored TPU elastic fiber material, comprising the following steps:
[0034] Step 1: Under a protective atmosphere, 50 parts of polytetramethylene ether glycol and 10 parts of diphenylmethane-4,4'-diisocyanate were mixed, the temperature was raised to 80°C, and the reaction was carried out for 3 hours. Then the mixture was cooled to 30°C, 100 parts of N,N-dimethylacetamide were added, and 14 parts of ethylenediamine solution (concentration of 23wt%) were added dropwise. The mixture was stirred for another 3 hours to obtain the spinning solution.
[0035] Step 2: Add the modifier to N,N-dimethylacetamide and stir until homogeneous to obtain a modifier solution (concentration 35wt%); mix the modifier solution with the spinning solution and stir continuously. After vacuum degassing, spin to obtain TPU elastic fiber material; wherein, the mass ratio of the modifier solution to the spinning solution is 3:100.
[0036] The modifier is prepared as follows: Under a protective atmosphere, 12 parts of the modified monomer are added to 60 parts of N,N-dimethylacetamide and stirred evenly at 70°C. Then, 2 parts of bismuth neodecanoate are added and stirred evenly again. After that, 20 parts of dicyclohexylmethane-4,4'-diisocyanate solution (concentration of 25wt%) are added dropwise to the above system and stirred at 70°C for 2 hours. After the reaction is completed, water is added to the system and then vacuum dried at 40°C to obtain the modifier.
[0037] The preparation process of the modified monomer is as follows:
[0038] S1: Mix 12 parts of p-hydroxybenzaldehyde, 10 parts of N-aminoethylpiperazine, and 100 parts of isopropanol, raise the temperature to 75°C, stir and react for 8 hours. After the reaction is complete, remove the isopropanol by rotary evaporation to obtain intermediate A.
[0039] S2: Under a protective atmosphere, 12 parts of intermediate A were added to 80 parts of tetrahydrofuran, cooled to 5°C, and 18 parts of a tetrahydrofuran solution of methyl dichlorophosphate (concentration 25wt%) were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C and the reaction was carried out for 8 hours. The mixture was then cooled to room temperature, filtered, washed, and dried to obtain the modified monomer.
[0040] Example 3: A method for preparing a colored TPU elastic fiber material, comprising the following steps:
[0041] Step 1: Under a protective atmosphere, 45 parts of polytetramethylene ether glycol and 9 parts of diphenylmethane-4,4'-diisocyanate were mixed, the temperature was raised to 80°C, and the reaction was carried out for 2.5 h. Then, the mixture was cooled to 30°C, 90 parts of N,N-dimethylacetamide were added, and 13.5 parts of ethylenediamine solution (concentration of 23 wt%) were added dropwise. The mixture was stirred for another 2.5 h to obtain the spinning solution.
[0042] Step 2: Add the modifier to N,N-dimethylacetamide and stir until homogeneous to obtain a modifier solution (concentration of 35wt%); mix the modifier solution with the spinning solution and stir continuously. After vacuum degassing, spin to obtain TPU elastic fiber material; wherein, the mass ratio of the modifier solution to the spinning solution is 2:100.
[0043] The modifier was prepared as follows: Under a protective atmosphere, 11 parts of the modifier monomer were added to 55 parts of N,N-dimethylacetamide and stirred evenly at 70°C. Then, 1.5 parts of bismuth neodecanoate were added and stirred evenly again. After that, 19 parts of dicyclohexylmethane-4,4'-diisocyanate solution (concentration of 25wt%) were added dropwise to the above system and stirred at 70°C for 1.5 h. After the reaction was completed, water was added to the system and then vacuum dried at 40°C to obtain the modifier.
[0044] The preparation process of the modified monomer is as follows:
[0045] S1: Mix 11 parts of p-hydroxybenzaldehyde, 9.5 parts of N-aminoethylpiperazine, and 90 parts of isopropanol, raise the temperature to 75°C, stir and react for 7 hours. After the reaction is complete, remove the isopropanol by rotary evaporation to obtain intermediate A.
[0046] S2: Under a protective atmosphere, 11 parts of intermediate A were added to 65 parts of tetrahydrofuran, cooled to 2.5°C, and 15 parts of a tetrahydrofuran solution of methyl dichlorophosphate (concentration 25wt%) were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C, and the reaction was carried out for 7 hours. The mixture was then cooled to room temperature, filtered, washed, and dried to obtain the modified monomer.
[0047] Comparative Example 1: No modifier solution was added, as follows:
[0048] Under a protective atmosphere, 45 parts of polytetramethylene ether glycol and 9 parts of diphenylmethane-4,4'-diisocyanate were mixed, the temperature was raised to 80°C, and the reaction was carried out for 2.5 h. Then, the mixture was cooled to 30°C, 90 parts of N,N-dimethylacetamide were added, and 13.5 parts of ethylenediamine solution (concentration of 23 wt%) were added dropwise. The mixture was stirred for another 2.5 h to obtain a spinning solution. After vacuum degassing, the solution was spun to obtain TPU elastic fiber material.
[0049] Comparative Example 2: The mass ratio of the modifier solution to the spinning solution was 0.5:100; details are as follows:
[0050] Step 1: Under a protective atmosphere, 45 parts of polytetramethylene ether glycol and 9 parts of diphenylmethane-4,4'-diisocyanate were mixed, the temperature was raised to 80°C, and the reaction was carried out for 2.5 h. Then, the mixture was cooled to 30°C, 90 parts of N,N-dimethylacetamide were added, and 13.5 parts of ethylenediamine solution (concentration of 23 wt%) were added dropwise. The mixture was stirred for another 2.5 h to obtain the spinning solution.
[0051] Step 2: Add the modifier to N,N-dimethylacetamide and stir until homogeneous to obtain a modifier solution (concentration of 35wt%); mix the modifier solution with the spinning solution and stir continuously. After vacuum degassing, spin to obtain TPU elastic fiber material; wherein, the mass ratio of the modifier solution to the spinning solution is 6:100.
[0052] The modifier was prepared as follows: Under a protective atmosphere, 11 parts of the modifier monomer were added to 55 parts of N,N-dimethylacetamide and stirred evenly at 70°C. Then, 1.5 parts of bismuth neodecanoate were added and stirred evenly again. After that, 19 parts of dicyclohexylmethane-4,4'-diisocyanate solution (concentration of 25wt%) were added dropwise to the above system and stirred at 70°C for 1.5 h. After the reaction was completed, water was added to the system and then vacuum dried at 40°C to obtain the modifier.
[0053] The preparation process of the modified monomer is as follows:
[0054] S1: Mix 11 parts of p-hydroxybenzaldehyde, 9.5 parts of N-aminoethylpiperazine, and 90 parts of isopropanol, raise the temperature to 75°C, stir and react for 7 hours. After the reaction is complete, remove the isopropanol by rotary evaporation to obtain intermediate A.
[0055] S2: Under a protective atmosphere, 11 parts of intermediate A were added to 65 parts of tetrahydrofuran, cooled to 2.5°C, and 15 parts of a tetrahydrofuran solution of methyl dichlorophosphate (concentration 25wt%) were slowly added dropwise. After the addition was complete, the temperature was raised to 65°C, and the reaction was carried out for 7 hours. The mixture was then cooled to room temperature, filtered, washed, and dried to obtain the modified monomer.
[0056] Testing experiment:
[0057] (1) 0.2 g of the fibers obtained in the examples and comparative examples were added to 200 mL of Acid Orange 7 dye solution with a concentration of 0.05 g / L, with a bath ratio of 1000:1; dyeing was carried out in a constant temperature shaker at 60 °C and the shaker speed was 120 rpm / min. The pH of the dye solution was adjusted to 3 using a buffer solution, and the equilibrium adsorption amount was recorded;
[0058] (2) The limiting oxygen index of the fibers obtained from the comparative examples of the embodiments was measured;
[0059] (3) The elastic recovery rate of the fibers obtained from the comparative examples of the embodiments was tested according to standard FZ / T 50007-2012; the data obtained are shown in Table 1:
[0060] Table 1
[0061] project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Equilibrium adsorption capacity (mg / g) 11.5 11.3 11.8 2.8 5.6 Limiting oxygen index (%) 27.3 27.1 28.4 19.1 22.5 Elastic recovery rate (%) 90.7 90.6 91.3 93.7 76.5
[0062] Conclusion: This invention successfully prepared a colored TPU elastic fiber material with excellent dyeing performance, flame retardancy, and good mechanical properties by introducing a modifier with a specific structure. Experimental results show that, compared with Comparative Example 1 without modifier, the fibers prepared in Examples 1 to 3 exhibited significantly increased equilibrium adsorption capacity (11.3-11.8 mg / g) and a significantly improved limiting oxygen index (27.1%-28.4%) under acidic dye conditions, indicating that their dyeing and flame retardant properties were effectively improved. Although the elastic recovery rate decreased slightly (90.6%-91.3%), it remained at a high level, indicating that the modified fiber achieved a good balance in overall performance. In Comparative Example 2, due to excessive modifier addition (mass ratio 6:100), the original microphase separation structure of the polyurethane was severely damaged, resulting in excessive disorder and looseness in the hard segment region, which could not effectively serve as physical crosslinking points, thus causing a significant decrease in the elastic recovery rate (76.5%), indicating that excessive modifier can impair the mechanical properties of the material.
[0063] Therefore, the amount of modifier added should be controlled within an appropriate range to achieve the optimal balance between dyeability, flame retardancy and mechanical properties.
[0064] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0065] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.
Claims
1. A method for preparing a colored TPU elastic fiber material, characterized in that, Includes the following steps: Step 1: Under a protective atmosphere, polytetramethylene ether glycol and diphenylmethane-4,4'-diisocyanate are mixed, the temperature is raised to 80°C, and the reaction is carried out for 2-3 hours. Then, the mixture is cooled to 30°C, N,N-dimethylacetamide is added, followed by the dropwise addition of ethylenediamine solution. The mixture is stirred for another 2-3 hours to obtain the spinning solution. Step 2: Add the modifier to N,N-dimethylacetamide and stir until homogeneous to obtain a modifier solution; The modifier solution is mixed with the spinning solution and stirred continuously. After vacuum degassing, the mixture is spun to obtain TPU elastic fiber material. The modifier is prepared as follows: Under a protective atmosphere, the modifier monomer is added to N,N-dimethylacetamide and stirred evenly at 70°C. Then, bismuth neodecanoate is added and stirred evenly again. After that, dicyclohexylmethane-4,4'-diisocyanate solution is added dropwise to the above system and stirred at 70°C for 1-2 hours. After the reaction is completed, water is added to the system and then vacuum dried at 40°C to obtain the modifier. The preparation process of the modified monomer is as follows: S1: Mix p-hydroxybenzaldehyde, N-aminoethylpiperazine and isopropanol, raise the temperature to 75°C, stir and react for 6-8 hours. After the reaction is complete, remove isopropanol by rotary evaporation to obtain intermediate A. S2: Under a protective atmosphere, intermediate A is added to tetrahydrofuran, cooled to 0-5℃, and a tetrahydrofuran solution of methyl dichlorophosphate is slowly added dropwise. After the addition is complete, the temperature is raised to 65℃, and the reaction is carried out for 6-8 hours. The mixture is then cooled to room temperature, filtered, washed, and dried to obtain the modified monomer.
2. The method for preparing a colored TPU elastic fiber material according to claim 1, characterized in that, The raw materials for preparing the spinning solution include the following components: by weight, 40-50 parts of polytetramethylene ether glycol, 8-10 parts of diphenylmethane-4,4'-diisocyanate, 80-100 parts of N,N-dimethylacetamide, and 13-14 parts of ethylenediamine solution; wherein the concentration of the ethylenediamine solution is 23 wt%.
3. The method for preparing a colored TPU elastic fiber material according to claim 1, characterized in that, The concentration of the modifier solution is 35 wt%.
4. The method for preparing a colored TPU elastic fiber material according to claim 1, characterized in that, The mass ratio of the modifier solution to the spinning solution is 1-3:
100.
5. The method for preparing a colored TPU elastic fiber material according to claim 1, characterized in that, The raw materials for preparing the modifier include the following components: by weight, 10-12 parts of the modifying monomer, 50-60 parts of N,N-dimethylacetamide, 1-2 parts of bismuth neodecanoate, and 18-20 parts of dicyclohexylmethane-4,4'-diisocyanate solution; wherein the concentration of the dicyclohexylmethane-4,4'-diisocyanate solution is 25wt%.
6. The method for preparing a colored TPU elastic fiber material according to claim 1, characterized in that, The raw materials for preparing intermediate A include the following components: by weight, 10-12 parts of p-hydroxybenzaldehyde, 9-10 parts of N-aminoethylpiperazine, and 80-100 parts of isopropanol.
7. The method for preparing a colored TPU elastic fiber material according to claim 1, characterized in that, The raw materials for preparing the modified monomer include the following components: by weight, 10-12 parts of intermediate A, 50-80 parts of tetrahydrofuran, and 12-18 parts of tetrahydrofuran solution of methyl dichlorophosphate. The concentration of the tetrahydrofuran solution of methyl dichlorophosphate is 25 wt%.
8. The TPU elastic fiber material obtained by the preparation method of a colored TPU elastic fiber material according to any one of claims 1-7.