A green anti-fibrillation finishing method for lyocell fabric

Abstract

The application discloses a kind of anti-fibrillation green finishing method for lyocell fabric, comprising: (1), preparation concentration is 2-3% cationic modification treatment solution;(2), lyocell fabric is soaked in above-mentioned treatment solution;(3), set the speed of infrared dyeing machine to 60r / min, from 20 ℃ to 55-65 ℃ with 3 ℃ / min, continue to run 25-35min, again with 6 ℃ / min to 40 ℃;(4), rinse clean with water and dry at 60 ℃;(5), preparation concentration is 1-5g / L polyacrylic acid emulsion;(6), cationic modified lyocell fabric is soaked in polyacrylic acid emulsion;(7), set the speed of infrared dyeing machine to 60r / min, from 20 ℃ to 55-65 ℃ with 3 ℃ / min, continue to run 25-35min, again with 6 ℃ / min to 40 ℃;(8), first pre-dry, then use 140-160 ℃ high temperature baking 4-6min.The application effectively reduces the fiber fibrillation tendency in the process of lyocell fabric production and use, solves the problem of fiber strength loss, and greatly reduces chemical additive consumption and environmental pollution.

Description

Technical Field

[0001] This invention relates to the field of functional finishing technology for textiles, and in particular to a green finishing method for preventing fibrillation of lyocell fabrics. Background Technology

[0002] Lyocell fiber is a regenerated cellulose fiber spun from wood pulp dissolved in NMMO solution. Because its production process is non-toxic and pollution-free, and the solvents used are recyclable, it is hailed as a new type of green fiber for the future. Lyocell fiber offers comfort comparable to cotton, possessing the feel of silk and the drape of viscose, along with excellent moisture absorption and breathability, and dimensional stability after washing. Combining the advantages of synthetic fibers and natural cellulose fibers, it is one of the most promising and well-received textile raw materials in the market this century.

[0003] However, during the drawing stage of lyocell spinning, the crystallization of the fiber tends to align more longitudinally, resulting in high crystallinity and orientation. This leads to a significantly lower transverse bonding force between the fiber macromolecular chains compared to the longitudinal bonding force. This pronounced anisotropy, coupled with the presence of numerous active free hydroxyl groups in the amorphous regions of the fiber, causes lyocell fibers to exhibit a high transverse wet swelling rate when immersed in aqueous solutions. When the amorphous regions of the fiber expand to a certain extent, some hydrogen bonds between the macromolecular chains are broken, weakening the bonding force between fibrils. If the fibers are simultaneously subjected to external stresses such as rubbing or friction between fibers, fibrillation can easily occur. In cases of severe fibrillation, the resulting fibrils can entangle into balls on the fabric surface, affecting the fabric's appearance.

[0004] Currently, the most widely used method for controlling fibrillation in lyocell fibers is post-treatment. This involves using a crosslinking agent and high-temperature treatment during the dyeing and finishing stage to form chemical bonds between cellulose molecular chains, thereby inhibiting fibrillation in ordinary lyocell fibers. The aim is to increase the lateral forces between fibrils in lyocell fibers. Cellulose macromolecules contain numerous hydroxyl functional groups, which can react with the crosslinking agent to generate ethers, esters, and other products. While the traditional and widely used high-temperature crosslinking process can significantly improve the fibrillation resistance of lyocell fibers, some drawbacks remain. Currently, the most typical crosslinking agents are 1,3,5-triacryloyl-hexahydro-1,3,5-triazine (TAHT) and N,N-dihydroxymethyldihydroxyethyl urea (DMDHEU). Both of these crosslinking agents can effectively reduce fibrillation after mechanical abrasion of fibers in a wet state. However, DMDHEU typically requires higher curing temperatures, and the textile fibers suffer significant strength loss after crosslinking. Furthermore, both crosslinking agents are toxic. Polycarboxylic acids (PCAs) are considered promising crosslinking agents, with citric acid (CA) being one of the most common and environmentally friendly. However, the commercial application of CA in the textile industry remains negligible, primarily due to discoloration caused by byproducts of its decomposition upon heating. 1,2,3,4-Butanetetracarboxylic acid (BTCA) is a more efficient crosslinking agent than CA and does not cause yellowing; however, its relatively high cost limits its industrial application.

[0005] Therefore, compared with the traditional cross-linking method for preventing fibrillation, how to make it suitable for mass production in factories, shorten the process flow, reduce costs, effectively reduce the tendency of fiber fibrillation during the production and use of Lyocell fabrics, solve the problem of fiber strength loss, improve the overall quality of the fabric, and greatly reduce the consumption of chemical auxiliaries, with no formaldehyde release in the process, has become a problem that technicians in the field of functional finishing of Lyocell fabrics urgently need to solve. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the technical problem to be solved by the present invention is to provide a green finishing method for preventing fibrillation of lyocell fabrics, which can effectively reduce the tendency of fiber fibrillation during the production and use of lyocell fabrics, solve the problem of fiber strength loss, improve the overall quality of the fabric, and greatly reduce the consumption of chemical auxiliaries and reduce environmental pollution.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a green finishing method for preventing fibrillation of lyocell fabrics, comprising the following steps:

[0008] I. Cationic Modification:

[0009] (1) Dissolve polydimethyldiallylammonium chloride in deionized water to prepare a 2-3% cationic modification treatment solution for later use;

[0010] (2) Transfer the cationic modified treatment solution to the dyeing vat of the infrared dyeing machine, and immerse the Lyocell fabric in the above treatment solution at a liquor ratio of 1:15-1:25.

[0011] (3) Set the infrared dyeing machine speed to 60r / min, start from 20℃ and heat up to 55-65℃ at a rate of 3℃ / min, continue to run at 55-65℃ for 25-35min, and then cool down to 40℃ at a rate of 6℃ / min.

[0012] (4) After completion, rinse with water and dry at 60°C to obtain cationic modified Lyocell fabric;

[0013] II. Anionic polymer emulsion treatment:

[0014] (5) Prepare a polyacrylic acid emulsion with a concentration of 1-5 g / L for later use;

[0015] (6) Transfer the polyacrylic emulsion to the dyeing vat of the infrared dyeing machine, and immerse the cationic modified Lyocell fabric in the polyacrylic emulsion at a liquor ratio of 1:15-1:25.

[0016] (7) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 55-65℃ at a rate of 3℃ / min, continue running at 55-65℃ for 25-35 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0017] III. Pre-drying and baking treatment:

[0018] (8) The Lyocell fabric processed in step (7) is first pre-dried at 100℃ for 8-12 minutes, and then baked at 140-160℃ for 4-6 minutes to obtain the Lyocell fabric that is resistant to fibrillation.

[0019] In the above-mentioned green finishing method for preventing fibrillation of Lyocell fabrics, the concentration of polydimethyldiallyl ammonium chloride in the cationic modification treatment solution of step (1) is 2.5%.

[0020] In the above-mentioned green finishing method for preventing fibrillation of Lyocell fabrics, in step (2), the ratio of the cationic modification treatment solution to the Lyocell fabric is 1:20.

[0021] In the above-mentioned green finishing method for preventing fibrillation of Lyocell fabrics, in step (3), the temperature is increased from 20°C to 60°C at a rate of 3°C / min, and then continued to run at 60°C for 30min.

[0022] In the above-mentioned green finishing method for preventing fibrillation of lyocell fabrics, the concentration of polyacrylic acid emulsion in step (5) is 3 g / L.

[0023] In the above-mentioned green finishing method for preventing fibrillation of lyocell fabrics, in step (6), the bath ratio of polyacrylic acid emulsion to cationic modified lyocell fabric is 1:20.

[0024] In the above-mentioned green finishing method for preventing fibrillation of Lyocell fabrics, in step (7), the temperature is increased from 20°C to 60°C at a rate of 3°C / min, and then continued to run at 60°C for 30min.

[0025] In the above-mentioned green finishing method for preventing fibrillation of Lyocell fabrics, in step (8), the Lyocell fabric is first pre-dried at 100°C for 10 minutes, and then baked at 150°C for 5 minutes.

[0026] The advantages of this invention's green finishing method for preventing fibrillation in lyocell fabrics are as follows: This invention uses adsorption instead of traditional high-temperature crosslinking. Because the quaternary ammonium groups in the cationic modifier are positively charged, they can be adsorbed onto the lyocell fibers through electrostatic attraction. After modification with the cationic modifier, the surface of the lyocell fibers changes from negative to positive charge. Then, polyacrylic acid is ionized in water to form negatively charged carboxylate ions, which are adsorbed onto the lyocell fibers modified with the cationic modifier through electrostatic attraction. High-temperature baking then melts and diffuses the adsorbed polymer particles, forming a film on the fiber surface. The surface structure of polydimethyldiallylammonium chloride-modified lyocell knitted fabric treated with polyacrylic acid emulsion is significantly improved, reducing transverse swelling and axial splitting of the fibers, thereby reducing the formation of nanoscale fibrils. It also enhances the lubricity of the fiber surface, reduces friction and entanglement between fibers, and forms a thin film on the fiber surface covering the stripped fibrils. This film effectively prevents further peeling and shedding of the fibrils, improves the durability and stability of the fibers, and fundamentally solves the problems of fiber strength damage, fabric yellowing and high cost caused by traditional high-temperature crosslinking. It has obvious prospects for industrial application. Attached Figure Description

[0027] Figure 1 This is a process flow diagram of the green finishing method for preventing fibrillation of lyocell fabrics according to the present invention;

[0028] Figure 2 SEM images showing the surface of untreated Lyocell fabric treated with 1 g / L polyacrylic emulsion under the process conditions of Example 2 after washing, magnified 300 times.

[0029] Figure 3SEM images showing the surface of untreated Lyocell fabric treated with 3 g / L polyacrylic emulsion under the process conditions of Example 2 after washing, magnified 300 times.

[0030] Figure 4 SEM images showing the surface of untreated Lyocell fabric treated with 5 g / L polyacrylic emulsion under the process conditions of Example 2 after washing, magnified 300 times.

[0031] Figure 5 This is a bursting strength test diagram of the Lyocell knitted fabric after treatment in Example 2 of the present invention;

[0032] Figure 6 This is a test diagram of the swelling rate of fibers in the lyocell knitted fabric treated in Example 2 of the invention under wet conditions;

[0033] Figure 7 This is a 5000x magnified SEM image of the surface of the Lyocell knitted fabric after processing in Example 2 of the present invention.

[0034] Figure 8 A comparison image showing the whiteness test results of Lyocell fabric before and after processing. Detailed Implementation

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] In the description of this invention, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative purposes and do not impose numerical requirements or establish an order. The term "multiple" means "two or more".

[0037] like Figure 1 As shown, a green finishing method for preventing fibrillation of lyocell fabrics includes the following steps:

[0038] I. Cationic Modification:

[0039] (1) Dissolve polydimethyldiallylammonium chloride in deionized water to prepare a 2-3% cationic modification treatment solution for later use;

[0040] (2) Transfer the cationic modified treatment solution to the dyeing vat of the infrared dyeing machine, and immerse the Lyocell fabric in the above treatment solution at a liquor ratio of 1:15-1:25.

[0041] (3) Set the infrared dyeing machine speed to 60r / min, start from 20℃ and heat up to 55-65℃ at a rate of 3℃ / min, continue to run at 55-65℃ for 25-35min, and then cool down to 40℃ at a rate of 6℃ / min.

[0042] (4) After completion, rinse with water and dry at 60°C to obtain cationic modified Lyocell fabric;

[0043] II. Anionic polymer emulsion treatment:

[0044] (5) Prepare a polyacrylic acid emulsion with a concentration of 1-5 g / L for later use;

[0045] (6) Transfer the polyacrylic emulsion to the dyeing vat of the infrared dyeing machine, and immerse the cationic modified Lyocell fabric in the polyacrylic emulsion at a liquor ratio of 1:15-1:25.

[0046] (7) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 55-65℃ at a rate of 3℃ / min, continue running at 55-65℃ for 25-35 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0047] III. Pre-drying and baking treatment:

[0048] (8) The Lyocell fabric processed in step (7) is first pre-dried at 100℃ for 8-12 minutes, and then baked at 140-160℃ for 4-6 minutes to obtain the Lyocell fabric that is resistant to fibrillation.

[0049] The cationic modifier used in this invention, polydimethyldiallylammonium chloride (PDADMAC) (40% solid content), was purchased from Shandong Yousuo Chemical Technology Co., Ltd.; the anionic polymer emulsion, polyacrylic acid emulsion (PAA) (45% solid content), was purchased from Shanghai Kangdun New Materials Co., Ltd.

[0050] In the finishing method of this invention, during the cationic modification stage, a slower heating rate (3℃ / min) allows the polymer to be more uniformly adsorbed onto the fiber surface. Appropriate temperature and time can promote the thermal motion of PDADMAC molecules. Too low a temperature leads to a low adsorption rate, while too high a temperature may cause PDADMAC degradation or damage to the lyocell fiber structure. Rapid cooling (6℃ / min) facilitates the formation of a dense and stable cationic layer of PDADMAC molecules on the fiber surface. During the anionic polymer emulsion treatment stage, a slow heating rate (3℃ / min) promotes the full extension of the PAA and PDADMAC molecular chains, enhancing the electrostatic interaction between them. 60℃ is close to the optimal reaction temperature for PDADMAC, accelerating the adsorption of PAA and PDADMAC while avoiding fiber damage. At high temperatures, the polymer chain segments move actively, which is beneficial for forming a dense composite film with a uniform charge distribution. Rapid cooling prevents molecular chain retraction or rearrangement, maintaining the high charge density and uniformity of the film. During the pre-drying and baking stages, pre-drying at 100℃ can efficiently remove residual moisture from Lyocell fabrics and Lyocell fibers, promote the dehydration condensation of the PAA-PDADMAC complex, and improve the wash-resistance of the Lyocell fiber surface film.

[0051] The present application will be specifically described below through specific embodiments. The following embodiments are only some embodiments of the present application and are not intended to limit the present application.

[0052] Example 1:

[0053] A green finishing method for preventing fibrillation in lyocell fabrics includes the following steps:

[0054] I. Cationic Modification:

[0055] (1) Dissolve polydimethyldiallylammonium chloride in deionized water to prepare a 2% cationic modification treatment solution for later use;

[0056] (2) Transfer the cationic modified treatment solution to the dyeing vat of the infrared dyeing machine, and immerse the Lyocell fabric in the above treatment solution at a liquor ratio of 1:15.

[0057] (3) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 55℃ at a rate of 3℃ / min, continue running at 55℃ for 35 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0058] (4) After completion, rinse with water and dry at 60°C to obtain cationic modified Lyocell fabric;

[0059] II. Anionic polymer emulsion treatment:

[0060] (5) Prepare a polyacrylic acid emulsion with a concentration of 1 g / L for later use;

[0061] (6) Transfer the polyacrylic emulsion to the dyeing vat of the infrared dyeing machine, and immerse the cationic modified Lyocell fabric in the polyacrylic emulsion at a liquor ratio of 1:15.

[0062] (7) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 55℃ at a rate of 3℃ / min, continue running at 55℃ for 35 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0063] III. Pre-drying and baking treatment:

[0064] (8) The Lyocell fabric processed in step (7) is first pre-dried at 100°C for 8 minutes, and then baked at 140°C for 6 minutes to obtain the Lyocell fabric that is resistant to fibrillation.

[0065] The green finishing method for preventing fibrillation of lyocell fabrics is characterized in that: in step (7), the temperature is increased from 20°C to 60°C at a rate of 3°C / min, and then run at 60°C for 30min.

[0066] The green finishing method for preventing fibrillation of Lyocell fabrics is characterized in that: in step (8), the Lyocell fabric is first pre-dried at 100°C for 10 minutes, and then baked at 150°C for 5 minutes.

[0067] Example 2:

[0068] A green finishing method for preventing fibrillation in lyocell fabrics includes the following steps:

[0069] I. Cationic Modification:

[0070] (1) Dissolve polydimethyldiallylammonium chloride in deionized water to prepare a 2.5% cationic modification treatment solution for later use;

[0071] (2) Transfer the cationic modified treatment solution to the dyeing vat of the infrared dyeing machine, and immerse the Lyocell fabric in the above treatment solution at a liquor ratio of 1:20.

[0072] (3) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 60℃ at a rate of 3℃ / min, continue running at 60℃ for 30 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0073] (4) After completion, rinse with water and dry at 60°C to obtain cationic modified Lyocell fabric;

[0074] II. Anionic polymer emulsion treatment:

[0075] (5) Prepare a polyacrylic acid emulsion with a concentration of 5 g / L for later use;

[0076] (6) Transfer the polyacrylic emulsion to the dyeing vat of the infrared dyeing machine, and immerse the cationic modified Lyocell fabric in the polyacrylic emulsion at a liquor ratio of 1:20.

[0077] (7) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 60℃ at a rate of 3℃ / min, continue running at 60℃ for 30 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0078] III. Pre-drying and baking treatment:

[0079] (8) The Lyocell fabric processed in step (7) is first pre-dried at 100°C for 10 minutes, and then baked at 150°C for 5 minutes to obtain the Lyocell fabric that is resistant to fibrillation.

[0080] The green finishing method for preventing fibrillation of Lyocell fabrics is characterized in that: in step (8), the Lyocell fabric is first pre-dried at 100°C for 10 minutes, and then baked at 150°C for 5 minutes.

[0081] Example 3:

[0082] A green finishing method for preventing fibrillation in lyocell fabrics includes the following steps:

[0083] I. Cationic Modification:

[0084] (1) Dissolve polydimethyldiallylammonium chloride in deionized water to prepare a 3% cationic modification treatment solution for later use;

[0085] (2) Transfer the cationic modified treatment solution to the dyeing vat of the infrared dyeing machine, and immerse the Lyocell fabric in the above treatment solution at a liquor ratio of 1:25.

[0086] (3) Set the infrared dyeing machine speed to 60r / min, start from 20℃ and heat up to 65℃ at a rate of 3℃ / min, continue running at 65℃ for 25min, and then cool down to 40℃ at a rate of 6℃ / min.

[0087] (4) After completion, rinse with water and dry at 60°C to obtain cationic modified Lyocell fabric;

[0088] II. Anionic polymer emulsion treatment:

[0089] (5) Prepare a polyacrylic acid emulsion with a concentration of 3 g / L for later use;

[0090] (6) Transfer the polyacrylic emulsion to the dyeing vat of the infrared dyeing machine, and immerse the cationic modified Lyocell fabric in the polyacrylic emulsion at a liquor ratio of 1:25.

[0091] (7) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 65℃ at a rate of 3℃ / min, continue to run at 55-65℃ for 25 min, and then cool down to 40℃ at a rate of 6℃ / min.

[0092] III. Pre-drying and baking treatment:

[0093] (8) The Lyocell fabric processed in step (7) is first pre-dried at 100°C for 12 minutes, and then baked at 160°C for 4 minutes to obtain the Lyocell fabric that is resistant to fibrillation.

[0094] The antifibrillation properties of Lyocell fabrics treated with the antifibrillation green finishing method of this invention are as follows:

[0095] Cut a 5cm x 5cm piece of lyocell knitted fabric. Place 50 steel balls evenly into five pure cotton woven fabric bags as pre-wash samples and add them to the dyeing vat. Add 100mL of 2g / L soap solution. In an SW-12A type wash fastness tester, raise the temperature from room temperature to 71℃, pause the machine, add the sample to the vat, and run at 71℃ for 45 minutes. Remove the sample, wash it three times at room temperature for 1 minute each time, and dry it in a forced-air drying oven at 60℃. This entire process is recorded as one wash. After three washes, retain the sample and observe the fibrillation of the lyocell knitted fabric under a scanning electron microscope (Phenom Pure, Holland).

[0096] like Figure 2-4 As shown, when the anionic polymer emulsion concentration is 1 g / L and the fabric is baked at 150°C, fibrils appear locally on the fabric after washing, but the fibrillation range is smaller than that of the untreated fabric, demonstrating an anti-fibrillation effect. When the anionic polymer emulsion concentration is 3 g / L and the fabric is baked at 150°C, fibrils begin to form on the surface of the fabric after washing, but the fibrillation range is smaller and the formed fibrils are shorter than those of the untreated fabric, demonstrating a good anti-fibrillation effect. When the anionic polymer emulsion concentration is 5 g / L and the fabric is baked at 150°C, almost no fibrillation occurs on the surface of the fabric after washing, showing a significant contrast with the untreated fabric, demonstrating a significant anti-fibrillation effect. Therefore, Example 2 of the present invention is the preferred embodiment.

[0097] like Figure 5As shown in the test results, the bursting strength of the Lyocell knitted fabric obtained by the anti-fibrillation green finishing method of this invention is 713 N, and the bursting strength of the PDADMAC-PAA-Lyocell knitted fabric is 764 N. This indicates that the strength of the Lyocell knitted fabric is improved after cationic modification and anionic polymer emulsion treatment. The elongation at break of the PDADMAC-PAA-Lyocell knitted fabric is greater than that of the untreated Lyocell knitted fabric, indicating that the Lyocell knitted fabric treated with both cationic modifier and anionic polymer emulsion requires more work to break. This shows that the treated Lyocell knitted fabric has higher toughness. Therefore, it can be proven that the process method of this invention not only does not affect the strength loss of Lyocell fibers, but also improves the strength and toughness of Lyocell fibers after finishing.

[0098] like Figure 6 As shown in the figure, the core-sheath structure of lyocell fibers makes them prone to high swelling rates in wet conditions. The untreated lyocell knitted fabric had a swelling rate of 70.6%. After treatment with cationic modification and anionic polymer emulsion, a thin film was formed on the surface of the lyocell knitted fabric. This film has a certain degree of hydrophobicity, effectively preventing water molecules from penetrating into the fiber interior, thus significantly reducing the swelling rate of the treated lyocell knitted fabric to 42%. This effectively improves the antifibrillation effect of lyocell fibers.

[0099] like Figure 7 As shown in the electron microscope image of the treated Lyocell knitted fabric magnified 5000 times, it can be seen that the finishing method of the present invention not only forms a uniform and continuous film on the fiber surface, but also forms an irregular and discontinuous film between adjacent Lyocell fibers. In some positions (such as inside the circle), a film is formed that adheres to adjacent fibers, while in other positions, a continuous film is not formed.

[0100] As is well known, the commonly used method to prevent fibrillation of lyocell fibers is high-temperature cross-linking. This involves chemical cross-linking, where a specific cross-linking agent reacts with the lyocell fibers to form chemical bonds between the cellulose molecular chains. This reaction with the hydroxyl groups on the lyocell fibers creates bonds between the fibers through molecular linking technology, forming bridges between different cellulose molecular chains and connecting the originally relatively independent chains. This restricts fibrillation and achieves the effect of preventing fibrillation. While cross-linking can achieve good anti-fibrillation effects, it often leads to a significant loss of fiber strength. This is because the cross-linking agent connects the cellulose molecular chains through chemical bonds to form a network structure, and excessively high cross-linking density can make the fibers brittle and reduce their flexibility. When external forces are applied, cross-linking points may become stress concentration points, making the fibers more prone to breakage under stress. Furthermore, high temperatures accelerate the fiber aging process, making them more susceptible to wear and breakage during use.

[0101] This invention, with its concept of film formation on the fiber surface and partially between fibers, has three advantages. First, due to the hydrophobic nature of the film, it slows down the fiber's water absorption and swelling. Compared to untreated fibers, the degree of fiber swelling is significantly reduced, and the interaction forces between fibrils are enhanced, leading to a decrease in fibril splitting. Second, the uniform and continuous film formed on the fiber surface can provide some protection to the fibers under external mechanical forces, reducing friction and further decreasing the tendency for fibril peeling. Third, the partially irregular and discontinuous film formed between fibers also improves the strength of Lyocell fabrics to some extent, as... Figure 5 The bursting strength test results show that this is due to the increased bonding force between fibers, which further proves that the finishing process of this invention actually improves the strength and toughness of Lyocell fibers.

[0102] like Figure 8 As shown, by comparison, it can be seen that the whiteness of the Lyocell fabric obtained by the finishing method of the present invention is 61.2%, compared with the whiteness of 63.2% of the untreated Lyocell fabric. The whiteness of the Lyocell fabric does not change much. Therefore, it can be seen that the green finishing method of the present invention effectively solves the problem of fabric discoloration caused by the byproducts of decomposition after heating in the traditional high-temperature crosslinking process.

[0103] In summary, compared with traditional high-temperature cross-linking and fibrillation methods, this invention employs the concept of adsorption film formation. In water, the polar groups such as hydroxyl groups on the surface of lyocell fibers ionize and become negatively charged, while the quaternary ammonium groups in the cationic modifier PDADMAC are positively charged, allowing them to be adsorbed onto the lyocell fibers through electrostatic attraction. After modification with PDADMAC, the surface of the lyocell fibers changes from negative to positive charge. Polyacrylic acid is a polymer containing a large number of carboxyl groups, which can ionize in water to form negatively charged carboxylate ions, which are adsorbed onto the PDADMAC-modified lyocell fibers through electrostatic attraction. High-temperature baking causes the adsorbed polymer particles to melt and diffuse, forming a film on the fiber surface. This reduces lateral swelling and axial splitting of the fibers, thereby reducing the formation of nanoscale fibrils. The study focuses on the formation of discontinuous films on the fiber surface through electrostatic adsorption. Lyocell knitted fabrics with low fibrillation tendency prepared by electrostatic adsorption have a simpler process, consume fewer chemicals, and release no formaldehyde compared to traditional fibrillation prevention methods. This method can be widely applied to the preparation of green fibrillation-resistant Lyocell knitted fabrics, achieving the goal of low-cost, formaldehyde-free green fibrillation prevention for Lyocell.

[0104] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should be protected by the present invention.

Claims

1. A green finishing method for preventing fibrillation in lyocell fabrics, characterized in that, Includes the following steps: I. Cationic Modification: (1) Dissolve polydimethyldiallylammonium chloride in deionized water to prepare a 2-3% cationic modification treatment solution for later use; (2) Transfer the cationic modified treatment solution to the dyeing vat of the infrared dyeing machine, and immerse the Lyocell fabric in the above treatment solution at a liquor ratio of 1:15-1:

25. (3) Set the infrared dyeing machine speed to 60r / min, start from 20℃ and heat up to 55-65℃ at a rate of 3℃ / min, continue to run at 55-65℃ for 25-35min, and then cool down to 40℃ at a rate of 6℃ / min. (4) After completion, rinse with water and dry at 60°C to obtain cationic modified Lyocell fabric; II. Anionic polymer emulsion treatment: (5) Prepare a polyacrylic acid emulsion with a concentration of 1-5 g / L for later use; (6) Transfer the polyacrylic emulsion to the dyeing vat of the infrared dyeing machine, and immerse the cationic modified Lyocell fabric in the polyacrylic emulsion at a liquor ratio of 1:15-1:

25. (7) Set the infrared dyeing machine speed to 60 r / min, start from 20℃ and heat up to 55-65℃ at a rate of 3℃ / min, continue running at 55-65℃ for 25-35 min, and then cool down to 40℃ at a rate of 6℃ / min. III. Pre-drying and baking treatment: (8) The Lyocell fabric processed in step (7) is first pre-dried at 100℃ for 8-12 minutes, and then baked at 140-160℃ for 4-6 minutes to obtain the Lyocell fabric that is resistant to fibrillation.

2. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In the cationic modification treatment solution of step (1), the concentration of polydimethyldiallyl ammonium chloride is 2.5%.

3. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In step (2), the ratio of the cationic modified treatment solution to the Lyocell fabric is 1:

20.

4. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In step (3), the temperature is increased from 20°C to 60°C at a rate of 3°C / min, and then run at 60°C for 30 minutes.

5. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In step (5), the concentration of the polyacrylic acid emulsion is 3 g / L.

6. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In step (6), the ratio of polyacrylic acid emulsion to cationic modified lyocell fabric is 1:

20.

7. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In step (7), the temperature is increased from 20°C to 60°C at a rate of 3°C / min, and then run at 60°C for 30 minutes.

8. The green finishing method for preventing fibrillation of lyocell fabrics according to claim 1, characterized in that: In step (8), the Lyocell fabric is first pre-dried at 100°C for 10 minutes, and then baked at 150°C for 5 minutes.

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