A water-lubricated textile durability-enhancing finishing agent and its preparation method

Abstract

This invention discloses a water-lubricating textile durability-preserving finishing agent, which is an emulsion formed by reactive triblock hydrophilic polyurethane and water. Its preparation method includes the following steps: dehydration of polyethylene glycol; reaction of hexamethylene diisocyanate trimer and butanone oxime to obtain partially capped hexamethylene diisocyanate; reaction of the partially capped hexamethylene diisocyanate with polyethylene glycol to obtain a product containing reactive triblock hydrophilic polyurethane; removal of the solvent from the product and dissolution with water to obtain a self-emulsifying emulsion. Based on water lubrication theory, the hydrophilic polyoxyethylene ether segments in the reactive triblock hydrophilic polyurethane can form a strongly bound hydration layer on the fabric surface, reducing interfacial friction during friction. During fabric washing, it increases lubrication and reduces wear, pilling, fuzzing, and fading caused by friction on the fabric surface. Cellulose fiber fabrics using this finishing agent retain their vibrant colors even after multiple washes.

Description

Technical Field

[0001] This invention belongs to the field of finishing agents for textile fabrics, specifically relating to a water-lubricated durable finishing agent for textiles and its preparation method. Background Technology

[0002] Textiles, especially cellulose fiber products, often exhibit increased fuzz and localized whitening at seams and overlapping areas after repeated washing, resulting in a noticeable worn-out appearance and severely impacting their overall appearance and durability. The main reason for this is that cellulose fibers swell in water, reducing the bond strength between the fibrils. Simultaneously, during washing, the mechanical tumbling of the drum, the impact of water flow, and the fabric's own rubbing cause the fibrils to separate or slip from the yarn, forming fuzz and pilling, leading to surface abrasion. On one hand, the fuzz diffuses light, resulting in a visually low color payoff; on the other hand, the shedding of fuzz and pilling causes fading and whitening. This phenomenon is even more pronounced in dark-colored products, which have higher dye concentrations and contain more uncovalently bonded and hydrolyzed dyes. Currently, there are no products specifically designed to solve this problem. The industry generally uses film-forming agents and color-enhancing agents to improve the post-wash aging effect, but the results are not ideal. Summary of the Invention

[0003] The purpose of this invention is to address the problem of whitening and reaging of cellulose fiber fabrics after washing. It provides a water-lubricating durable finishing agent for textiles and its preparation method. Based on water lubrication theory, this finishing agent utilizes the hydrophilic polyoxyethylene ether structure of its reactive triblock hydrophilic polyurethane. Through hydrogen bonds, it binds with water molecules to form a strongly bound hydration layer on the fabric surface. This hydration layer acts as a pressure-resistant water-lubricating layer between the two interfaces, preventing direct contact during friction and reducing interfacial friction. During fabric washing, it increases lubrication and reduces wear, pilling, and fading caused by friction. Cellulose fiber fabrics treated with this finishing agent retain their vibrant colors even after multiple washes.

[0004] The technical solution adopted by this invention to solve the above-mentioned technical problems is as follows: a water-lubricated textile durability-preserving finishing agent, wherein the finishing agent is an emulsion formed by reactive triblock hydrophilic polyurethane and water, and the structural formula of the reactive triblock hydrophilic polyurethane is:

[0005]

[0006] Wherein, R is methyl ethyl ketone oxime, and n is 1000 to 15000, preferably 3500 to 10000.

[0007] A method for preparing the above-mentioned water-lubricated textile durability-preserving finishing agent includes the following steps:

[0008] S1: Polyethylene glycol is dehydrated by vacuum distillation at 110℃ for 4 hours;

[0009] S2: To prevent explosive polymerization during the reaction, this invention employs a pre-capping method for synthesis, using methyl ethyl ketone oxime as the capping agent. Hexamethylene diisocyanate trimer (i.e., HDI trimer) and methyl ethyl ketone oxime are mixed at a molar mass ratio of 1:2, and then acetone is added as a solvent. The mass ratio of the added acetone to the sum of the masses of hexamethylene diisocyanate trimer and methyl ethyl ketone oxime is 1:1. The reaction is carried out at 60-70°C to cap approximately 2 / 3 of the isocyanate groups on the hexamethylene diisocyanate trimer, yielding the reactant.

[0010] S3: Dehydrated polyethylene glycol is added to the reactants obtained in step S2. The molar mass ratio of the added polyethylene glycol to the molar mass of the hexamethylene diisocyanate trimer in step S2 is 1:(2.2~2.4). The polymerization reaction is carried out at 60~80℃ to obtain a product containing reactive triblock hydrophilic polyurethane.

[0011] S4: The product obtained in step S3 is distilled at 100°C to remove the solvent. Then, water with a mass of 7 / 3 times that of the product after solvent removal is added and the mixture is stirred at high speed for 20 minutes to dissolve and emulsify the product. The resulting self-emulsifying emulsion is the water-lubricated textile durability-preserving finishing agent.

[0012] Preferably, the molecular weight of the polyethylene glycol is 1000 to 15000.

[0013] As a further preferred embodiment, the molecular weight of the polyethylene glycol is 3500 to 10000.

[0014] Preferably, the content of isocyanate groups in the hexamethylene diisocyanate trimer is 12-20%.

[0015] As a further preferred embodiment, the content of isocyanate groups in the hexamethylene diisocyanate trimer is 15-19%.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1) The water-lubricated textile durability-maintaining finishing agent of this invention is an emulsion formed by reactive triblock hydrophilic polyurethane and water. The reactive triblock hydrophilic polyurethane has four isocyanate groups (i.e., -NCO groups) blocked by methyl ethyl ketone oxime at both ends of its molecular chain. During high-temperature baking, these groups are unblocked, releasing free -NCO groups that react with -OH groups on the fabric, fixing them to the fabric surface and forming a ring-shaped brush structure. The two -CNO groups on the hexamethylene diisocyanate at one end react with the -OH groups on the cellulose, forming a small-span crosslink that strengthens the radial bonding force between adjacent fibers and improves the splitting of microfibers along the fiber axis. The crosslinking of the hexamethylene diisocyanate at both ends with the fibers forms a large-span bridging structure, fixing the ring-shaped brush. The hydrophilic polyoxyethylene ether segments in reactive triblock hydrophilic polyurethane bind with water molecules via hydrogen bonds, forming a strongly bound hydration layer on the fabric surface. This hydration layer acts as a pressure-resistant, water-lubricating layer between the two interfaces, preventing direct contact during friction and reducing interfacial friction. During fabric washing, it increases lubrication and reduces wear, pilling, and fading caused by friction. Cellulose fiber fabrics treated with this finishing agent retain their vibrant colors even after multiple washes.

[0018] 2) This invention synthesizes a reactive triblock hydrophilic polyurethane through the reaction of hexamethylene diisocyanate trimer, polyethylene glycol, and methyl ethyl ketone oxime. After dissolving in water, a finishing agent is prepared. Unlike traditional finishing methods that aim to preserve newness, this invention's finishing agent is based on the water lubrication theory, providing a new solution for improving the fading, whitening, and re-aging phenomena of cellulose fiber fabrics, especially dark-colored fabrics, after washing. Attached Figure Description

[0019] Figure 1 The infrared spectrum of the reactive triblock hydrophilic polyurethane in Example 1;

[0020] Figure 2 A photograph showing the worn surface of a black cotton fabric after washing;

[0021] Figure 3 A photograph showing the worn surface of a black Tencel fabric after washing;

[0022] Figure 4 To determine the surface friction coefficient of the treated fabric when it is wetted using a friction coefficient tester. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be noted that the following embodiments are only used to explain the present invention and cannot be used to limit the present invention. All technical solutions that are the same as or similar to the present invention are within the protection scope of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art, and the raw materials used are commercially available products.

[0024] The preparation method of the water-lubricated textile durability-preserving finishing agent in Example 1 includes the following steps:

[0025] S1: Polyethylene glycol 3500 was dehydrated by vacuum distillation at 110℃ for 4 hours.

[0026] S2: Using methyl ethyl ketone oxime as a capping agent, HDI trimer and methyl ethyl ketone oxime are mixed at a molar mass ratio of 1:2, and acetone is added as a solvent. The mass ratio of the added acetone to the sum of the masses of hexamethylene diisocyanate trimer and methyl ethyl ketone oxime is 1:1. The mixture is reacted at 60°C for 2 hours to block about 2 / 3 of the isocyanate groups on the HDI trimer, thus obtaining the reactant.

[0027] S3: Dehydrated polyethylene glycol is added to the reactants obtained in step S2. The molar mass ratio of the added polyethylene glycol to the molar mass of the HDI trimer in step S2 is 1:2.2 to 2.4. The polymerization reaction is carried out at 60°C for 2 hours to obtain a product containing reactive triblock hydrophilic polyurethane.

[0028] S4: The product obtained in step S3 is distilled at 100°C to remove the solvent. Then, water with a mass of 7 / 3 times that of the product after solvent removal is added and the mixture is stirred at high speed for 20 minutes to dissolve and emulsify the product. The resulting self-emulsifying emulsion is the water-lubricated textile durability-preserving finishing agent.

[0029] Example 2 describes a method for preparing a water-lubricated textile durability-maintaining finishing agent, comprising the following steps:

[0030] S1: Polyethylene glycol 6000 was dehydrated by vacuum distillation at 110℃ for 4 hours.

[0031] S2: Using methyl ethyl ketone oxime as a capping agent, HDI trimer and methyl ethyl ketone oxime were mixed at a molar mass ratio of 1:2, and acetone was added as a solvent. The ratio of the mass of acetone added to the sum of the masses of hexamethylene diisocyanate trimer and methyl ethyl ketone oxime was 1:1. The mixture was reacted at 65°C for 2 hours to block about 2 / 3 of the isocyanate groups on the HDI trimer, thus obtaining the reactant.

[0032] S3: Dehydrated polyethylene glycol is added to the reactants obtained in step S2. The molar mass ratio of the added polyethylene glycol to the molar mass of the HDI trimer in step S2 is 1:2.2 to 2.4. The polymerization reaction is carried out at 70°C for 3 hours to obtain a product containing reactive triblock hydrophilic polyurethane.

[0033] S4: The product obtained in step S3 is distilled at 100°C to remove the solvent. Then, water with a mass of 7 / 3 times that of the product after solvent removal is added and the mixture is stirred at high speed for 20 minutes to dissolve and emulsify the product. The resulting self-emulsifying emulsion is the water-lubricated textile durability-preserving finishing agent.

[0034] Example 3 describes a method for preparing a water-lubricated textile durability-maintaining finishing agent, comprising the following steps:

[0035] S1: Polyethylene glycol 10000 was dehydrated by vacuum distillation at 110℃ for 4 hours.

[0036] S2: Using methyl ethyl ketone oxime as a capping agent, HDI trimer and methyl ethyl ketone oxime are mixed at a molar mass ratio of 1:2, and acetone is added as a solvent. The mass ratio of the added acetone to the sum of the masses of hexamethylene diisocyanate trimer and methyl ethyl ketone oxime is 1:1. The mixture is reacted at 70°C for 2 hours to block about 2 / 3 of the isocyanate groups on the HDI trimer, thus obtaining the reactant.

[0037] S3: Dehydrated polyethylene glycol is added to the reactants obtained in step S2. The molar mass ratio of the added polyethylene glycol to the molar mass of the HDI trimer in step S2 is 1:2.2 to 2.4. The polymerization reaction is carried out at 70°C for 3 hours to obtain a product containing reactive triblock hydrophilic polyurethane.

[0038] S4: The product obtained in step S3 is distilled at 100°C to remove the solvent. Then, water with a mass of 7 / 3 times that of the product after solvent removal is added and the mixture is stirred at high speed for 20 minutes to dissolve and emulsify the product. The resulting self-emulsifying emulsion is the water-lubricated textile durability-preserving finishing agent.

[0039] The water-lubricated textile durability-preserving finishing agent of this invention is an emulsion formed by reactive triblock hydrophilic polyurethane and water. The structural formula of the reactive triblock hydrophilic polyurethane is as follows:

[0040]

[0041] Where R is methyl ethyl ketone oxime and n is 1000 to 15000.

[0042] Taking Example 1 as an example, the infrared spectrum of the reactive triblock hydrophilic polyurethane in the finishing agent prepared therein is as follows: Figure 1 As shown. Infrared spectrum shows 1680 cm⁻¹ -1The stretching vibration peak of the C=O group on the HDI trimer is at 3350 cm⁻¹. -1 and 1720cm -1 The absorption peaks at 1110 cm⁻¹ correspond to the stretching vibrations of NH and C=O in the urethane structure, respectively. -1 The peak at 2940 cm⁻¹ is a characteristic peak for polyoxyethylene ether COC. -1 2870cm -1 1510cm -1 and 1460cm -1 Corresponding to the stretching and bending vibrations of -CH2 and -CH3.

[0043] To verify the effect of the finishing agents prepared in Examples 1-3 on the preservation of color and appearance of the washed fabrics, the fabrics were washed and dried according to GB / T8629-2017 washing procedure 4N, with 5 washes. The original color fading and anti-pilling grades of the fabrics were evaluated after washing. Specifically, the finishing agents prepared in Examples 1-3 were used to perform preservation finishing on black cotton fabrics and black Tencel fabrics, respectively.

[0044] The specifications of the all-cotton fabric used are: 40s×40s, 112×82, 124g / m². 2 ;

[0045] The Tencel fabric used has the following specifications: 40s×40s, 120×80, 124g / m². 2 ;

[0046] The concentrations of the finishing agents used were 30 g / L, 60 g / L, and 90 g / L, respectively.

[0047] The finishing process used is as follows: two dips and two rolls (70% roll-off) → pre-drying (80℃, 3 min) → baking (160℃, 3 min).

[0048] Tables 1 and 2 show the color fading and pilling levels of the fabrics after washing. Figure 2 and Figure 3 These are photographs showing the wear and tear on the surface of fabrics after washing with the finishing agents prepared in Examples 1 to 3. Figure 4 To determine the surface friction coefficient of the treated fabric when wetted, a friction coefficient tester (ELB-MC01, Yinglai Platinum Shanghai Technology Co., Ltd.) was used, with a finishing agent concentration of 90 g / L. The friction coefficient testing method was as follows: the fabric to be tested was cut into 80*200 mm samples, adhered to the test surface, and approximately 20 mL of deionized water was added to the fabric surface to wet it. The normal load was set to 2 N, the sliding speed to 100 mm / min, the instrument was turned on, and the surface friction coefficient of the fabric was measured. Three parallel samples were tested, and the average value was taken.

[0049] Table 1. Retention effect of color and appearance of all-cotton black fabric after washing

[0050]

[0051] Table 2. Retention effect of color and appearance of black Tencel fabric after washing

[0052]

[0053] As shown in Tables 1 and 2, fabrics treated with the reactive triblock hydrophilic polyurethane finishing agent prepared according to this invention exhibit improved pilling and fuzzing grades by 1-1.5 grades after washing, and improved colorfastness grades by 1-1.5 grades. Figure 2 and Figure 3 It is evident that, regardless of whether it is Tencel or cotton fabric, surface abrasion improves with increasing polyethylene glycol molecular weight and finishing concentration. In Example 3, the surface abrasion was the least after washing, while in Example 1, the abrasion was more severe, but still an improvement over the original condition. Figure 4 As can be seen, the coefficient of friction of the fabric treated with the reactive triblock hydrophilic polyurethane finishing agent of the present invention is reduced in the wet state, and the coefficient of friction decreases with the increase of polyethylene glycol molecular weight. The results of fabric fading, pilling, and surface wear after washing are consistent with the results of fabric surface friction coefficient, indicating that the formation of a hydrophilic lubricating layer on the fabric surface can effectively reduce surface wear during washing and improve pilling and fading after washing.

Claims

1. A water-lubricated textile durable refreshment finish, characterized by, The finishing agent is an emulsion of a reaction type three-block hydrophilic polyurethane and water, and the reaction type three-block hydrophilic polyurethane has a structural formula as follows: wherein R is butanone oxime, and n is 1000-15000.

2. A process for the preparation of a water lubricant durable press finish for textile fabrics as claimed in claim 1, characterized in that, The method comprises the following steps: S1: polyethylene glycol is distilled under reduced pressure at 110 DEG C for 4 hours to remove water; S2: hexamethylene diisocyanate trimer and butanone oxime are mixed in a molar ratio of 1:2, and then acetone is added as a solvent, the ratio of the mass of acetone to the sum of the mass of hexamethylene diisocyanate trimer and butanone oxime is 1:1, and the reaction is carried out at 60-70 DEG C to close about 2 / 3 of the isocyanate groups on the hexamethylene diisocyanate trimer, thereby obtaining a reaction product; S3: the reaction product obtained in step S2 is added with dehydrated polyethylene glycol, the ratio of the molar mass of polyethylene glycol to the molar mass of hexamethylene diisocyanate trimer in step S2 is 1:(2.2-2.4), and the polymerization reaction is carried out at 60-80 DEG C, thereby obtaining a product containing a reaction type three-block hydrophilic polyurethane; S4: the product obtained in step S3 is distilled at 100 DEG C to remove the solvent, then 7 / 3 times the mass of water of the product after removal of the solvent is added, and high-speed stirring is carried out for 20 minutes to dissolve and emulsify the product, thereby obtaining a self-emulsifying emulsion which is a water-lubricated textile durable finishing agent.

3. The method for preparing a water-lubricated textile durable refresh ing finish according to claim 2, characterized by, The polyethylene glycol has a molecular weight of 1000-15000.

4. The method for preparing a water-lubricated textile durable refresh ing finish according to claim 3, characterized by, The polyethylene glycol has a molecular weight of 3500-10000.

5. The method for preparing a water lubricant durable textile refreshment finish according to claim 2, characterized in that, The content of isocyanate groups in the hexamethylene diisocyanate trimer is 12-20%.

6. The method for preparing a water lubricant durable textile refreshment finish according to claim 5, characterized in that, The content of isocyanate groups in the hexamethylene diisocyanate trimer is 15-19%.

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