Acetic acid-imitated easy-to-tear cloth and preparation method thereof

Abstract

The invention relates to the technical field of fabrics, in particular to acetic acid-imitated easy-to-tear cloth and a preparation method thereof. The preparation process of the acetic acid-imitated easy-to-tear cloth comprises the following steps: reacting cyanuric chloride and ethanolamine in 1, 2-dichloroethane to obtain hydroxylated triazine containing secondary amine; further modifying the carbon nano tube to obtain a hydroxylated triazine modified carbon nano tube; and mixing the modified polyester fiber with polyester chips, flame-retardant master batches and the like, and carrying out twin-screw extrusion and melt spinning to generate the modified polyester fiber. And performing weaving and alkali decrement treatment on the obtained fibers, and performing heat setting at high temperature to obtain the acetic acid-imitated easy-to-tear cloth. The fabric has the continuous brittle fracture characteristic, meanwhile, due to the synergistic structure of the hard-soft areas in the fibers, the fabric has small performance fluctuation under different alkali weight reduction conditions, the process adaptability and stability are high, and the fabric is suitable for being applied to the fields of clothes, medical fabric, industrial fabric and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fabric, in particular to an acetate-like easy-tear cloth and a preparation method thereof. BACKGROUND

[0002] Easy-tear cloth is a special functional textile material with directional tearing performance. Traditional easy-tear cloth is mainly prepared from acetate fiber, which has the characteristics of continuous brittle fracture along the tearing direction, neat fracture, no hairiness, and soft and silky hand feeling. However, acetate fiber easy-tear cloth has the disadvantages of poor washing resistance, easy wrinkling, low strength, and high price, which limits its wider application.

[0003] In recent years, synthetic fibers represented by polyester fibers have become important raw materials for developing new easy-tear cloth due to their excellent physical and mechanical properties and relatively low cost. However, polyester fibers themselves have high elongation at break and toughness, and often exhibit ductile fracture or brittle-ductile mixed fracture during tearing, which cannot achieve the continuous brittle fracture characteristics of acetate fiber easy-tear cloth. Therefore, how to regulate the fracture behavior of polyester fibers to exhibit continuous brittle fracture characteristics similar to acetate fiber has become a key technical challenge for developing acetate-like easy-tear cloth.

[0004] At present, the common methods for improving the tearing performance of polyester fibers include alkali reduction treatment. Alkali reduction treatment is to corrode the surface of polyester fibers with alkali solution to reduce the surface strength of the fibers and form a microporous structure, thereby reducing the energy absorption during tearing and promoting brittle fracture. However, simple alkali reduction treatment cannot accurately control the fracture behavior of the fibers, and the process window is narrow. Small changes in parameters such as bath ratio, temperature, and time can cause significant fluctuations in product performance, making it difficult for actual production. SUMMARY

[0005] Therefore, the purpose of the present application is to provide an acetate-like easy-tear cloth and a preparation method thereof to improve the fracture behavior of the acetate-like easy-tear cloth and the stability of the alkali reduction process.

[0006] To achieve the above purpose, the present application provides an acetate-like easy-tear cloth, which is obtained by weaving, alkali reduction, finishing, and heat setting of modified polyester fibers in sequence.

[0007] The preparation steps of the modified polyester fibers are as follows: S1: add cyanuric chloride and ethanolamine into 1,2-dichloroethane, heat to 78-82℃, stir and reflux for 7-9h, wash, and rotary evaporate to obtain a hydroxylated triazine containing secondary amine; S2: Add carbon nanotubes to a mixed solvent of deionized water and anhydrous ethanol, disperse by ultrasonication, add silane coupling agent KH-560, heat to 50-60℃, stir for 5-7 hours, centrifuge, wash, and vacuum dry to obtain epoxidized carbon nanotubes. S3: Add epoxidized carbon nanotubes to cyclohexanol, disperse by ultrasonication, then add hydroxylated triazine containing secondary amine, heat to 78-82℃, stir for 5-7 hours, centrifuge, wash, and vacuum dry to obtain hydroxylated triazine modified carbon nanotubes. S4: PET chips, flame retardant masterbatch, hydroxylated triazine modified carbon nanotubes and color masterbatch are mixed, vacuum dried, and then melt-spun through twin-screw extrusion to obtain modified polyester fibers.

[0008] Preferably, in step S1, the weight ratio of cyanuric chloride, ethanolamine, and 1,2-dichloroethane is 10:13-18:80-120.

[0009] Preferably, in step S2, the outer diameter of the carbon nanotube is 10-20 nm and the length is 0.5-2 μm.

[0010] Preferably, in step S2, the weight ratio of carbon nanotubes, deionized water, anhydrous ethanol and silane coupling agent KH-560 is 100:800-1200:150-250:8-12.

[0011] Preferably, in step S3, the weight ratio of epoxidized carbon nanotubes, cyclohexanol, and hydroxylated triazine containing secondary amine is 100:800-1200:15-25.

[0012] Preferably, the intrinsic viscosity of the PET chips in step S4 is 0.65-0.72 dL / g.

[0013] Preferably, in step S4, the weight ratio of PET chips, flame retardant masterbatch, hydroxylated triazine modified carbon nanotubes, and color masterbatch is 800-1200:65-95:50-70:28-32.

[0014] Preferably, the temperatures of each zone in the melt spinning process in step S4 are: zone 1 260-270℃, zone 2 275-285℃, zone 3 280-290℃, and the winding speed is 3000-3500m / min.

[0015] Preferably, the modified polyester fiber in step S4 has a specification of 84 dtex / 72f.

[0016] Furthermore, the present invention also provides a method for preparing an acetate-like easy-tear fabric, comprising the following steps: (1) Modified polyester fibers are woven on a loom to obtain modified polyester fabric; (2) The modified polyester fabric is immersed in an alkali-reducing impregnation solution with a bath ratio of 1:25, heated to 80-130℃ for 30-40 minutes, and then washed with water to obtain the alkali-reducing polyester fabric. (3) The alkali-reduced polyester fabric is subjected to two dips and two nips in the finishing solution, and then hot air set at 170-180℃ for 40-50s to obtain an imitation acetate easy-tear fabric.

[0017] Preferably, the weaving parameters in step (1) are 58-75 warp yarns / cm, 22-42 weft yarns / cm, and 1 / 1 plain weave.

[0018] Preferably, the alkali reduction impregnation solution in step (2) contains 7-9 g / L sodium hydroxide and 2-4 g / L penetrant.

[0019] Preferably, the finishing solution in step (3) contains 4-6 g / L of surface hardness modifier and 1-3 g / L of antistatic agent.

[0020] The beneficial effects of this invention are: The hydroxylated triazine-modified carbon nanotubes of this invention construct a unique microstructure network within a polyester matrix. This network comprises both a rigid framework (hard regions) formed by carbon nanotubes and flexible connecting segments (soft regions) provided by triazine molecules. This synergistic hard-soft region structure facilitates the formation of stress concentration regions within the polyester fiber, promoting the directional propagation of cracks along a predetermined direction, thereby achieving continuous brittle fracture characteristics. Simultaneously, this special structure buffers and regulates changes in material properties during the alkali reduction process, significantly improving process stability.

[0021] The key technical aspect of this invention is the chemical bonding between hydroxylated triazine and carbon nanotubes. A chemically bonded interfacial layer is formed through the ring-opening reaction of secondary amine groups with the epoxy groups on the surface of carbon nanotubes. This interfacial layer improves the uniformity of carbon nanotube dispersion in the polyester matrix, avoiding stress concentration caused by nanotube agglomeration. Furthermore, the hydroxyl groups of the hydroxylated triazine molecules form a hydrogen bond network with the polyester molecular chains, enhancing the interfacial adhesion between the filler and the matrix. This chemical modification leads to a change in the interfacial structure, resulting in a more uniform stress distribution in the material's microstructure and enabling efficient and directional release of fracture energy.

[0022] The acetate-like easy-tear fabric of the present invention exhibits excellent continuous brittle fracture behavior, with neat fiber breakage upon tearing. Furthermore, the acetate-like easy-tear fabric of the present invention shows minimal performance fluctuations under different alkali reduction conditions, exhibits strong process adaptability, and is beneficial for quality control and product consistency assurance in actual production, thereby improving production efficiency and product qualification rate.

[0023] The acetate-like easy-tear fabric provided by this invention has broad application prospects in clothing, medical fabrics and industrial fabrics, and can provide high-performance, high-quality new easy-tear materials for related industries. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0025] In the specific embodiments of this invention, the carbon nanotubes were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., with the product number C369044, an outer diameter of 10-20 nm, and a length of 0.5-2 μm; the flame retardant masterbatch was purchased from Jinan Bingyi Chemical Technology Co., Ltd., with the model number FR / MB-PET; and the color masterbatch was purchased from Shanghai Zhantong Industrial Co., Ltd., with the model number M4218.

[0026] Example 1:

[0027] (1) Add 10g of cyanuric chloride and 13g of ethanolamine to 80g of 1,2-dichloroethane, heat to 78℃, stir and reflux for 7h, wash the reaction solution with deionized water, concentrate the organic phase by rotary evaporation, and obtain hydroxylated triazine containing secondary amine. (2) Add 100g of carbon nanotubes to a mixed solvent of 800g of deionized water and 150g of anhydrous ethanol, sonicate for 20min, then add 8g of silane coupling agent KH-560, heat to 50℃, stir for 5h, centrifuge, wash three times with deionized water and anhydrous ethanol, and vacuum dry to obtain epoxidized carbon nanotubes. (3) Add 100g of epoxidized carbon nanotubes to 800g of cyclohexanol, sonicate for 20min, then add 15g of hydroxylated triazine containing secondary amine, heat to 78℃, stir for 5h, centrifuge, wash 3 times with anhydrous ethanol, and vacuum dry to obtain hydroxylated triazine modified carbon nanotubes. (4) Mix 800g of PET chips (intrinsic viscosity 0.68 dL / g), 65g of flame retardant masterbatch, 50g of hydroxylated triazine modified carbon nanotubes and 28g of color masterbatch, vacuum dry at 135℃ for 4h, and then melt spin through twin screw extrusion (temperature of each zone: zone 1 260℃, zone 2 275℃, zone 3 280℃, winding speed 3000m / min) to obtain modified polyester fiber with 84dtex / 72f; (5) Modified polyester fiber is woven on a 24 needle / cm loom with 58 warp yarns / cm and 42 weft yarns / cm, in 1 / 1 plain weave, to obtain modified polyester fabric. (6) The modified polyester fabric is immersed in an alkali-reducing impregnation solution (containing 7 g / L sodium hydroxide and 2 g / L penetrant JFC-2) at a bath ratio of 1:25, heated to 80°C for 30 min, and then washed with water to obtain the alkali-reducing polyester fabric. (7) The alkali-reduced polyester fabric is subjected to two dips and two nips in a finishing solution (containing 4 g / L surface hardness modifier H-880 and 1 g / L antistatic agent AS-200), and then hot air set at 170℃ for 40 s to obtain an imitation acetate easy-tear fabric.

[0028] Example 2:

[0029] (1) Add 10g of cyanuric chloride and 15g of ethanolamine to 100g of 1,2-dichloroethane, heat to 80℃, stir and reflux for 8h, wash the reaction solution with deionized water, concentrate the organic phase by rotary evaporation, and obtain hydroxylated triazine containing secondary amine. (2) Add 100g of carbon nanotubes to a mixed solvent of 1000g of deionized water and 200g of anhydrous ethanol, sonicate for 30min, then add 10g of silane coupling agent KH-560, heat to 55℃, stir for 6h, centrifuge, wash three times with deionized water and anhydrous ethanol, and vacuum dry to obtain epoxidized carbon nanotubes. (3) Add 100g of epoxidized carbon nanotubes to 1000g of cyclohexanol, sonicate for 30min, then add 20g of hydroxylated triazine containing secondary amine, heat to 80℃, stir for 6h, centrifuge, wash 3 times with anhydrous ethanol, and vacuum dry to obtain hydroxylated triazine modified carbon nanotubes. (4) Mix 1000g of PET chips (intrinsic viscosity 0.68 dL / g), 80g of flame retardant masterbatch, 60g of hydroxylated triazine modified carbon nanotubes and 35g of color masterbatch, vacuum dry at 135℃ for 4h, and then melt spin through twin screw extrusion (temperature of each zone: zone 1 265℃, zone 2 280℃, zone 3 285℃, winding speed 3200 m / min) to obtain modified polyester fiber with 84dtex / 72f; (5) Modified polyester fiber is woven on a 24 needle / cm loom with 58 warp yarns / cm and 42 weft yarns / cm, in 1 / 1 plain weave, to obtain modified polyester fabric. (6) The modified polyester fabric is immersed in an alkali-reducing impregnation solution (containing 8 g / L sodium hydroxide and 3 g / L penetrant JFC-2) with a bath ratio of 1:25. The temperature is raised to 85℃ for 35 min, and then washed with water to obtain the alkali-reducing polyester fabric. (7) The alkali-reduced polyester fabric is subjected to two dips and two nips in a finishing solution (containing 5 g / L surface hardness modifier H-880 and 2 g / L antistatic agent AS-200), and then hot air set at 175℃ for 45s to obtain an imitation acetate easy-tear fabric.

[0030] Example 3:

[0031] (1) Add 10g of cyanuric chloride and 18g of ethanolamine to 120g of 1,2-dichloroethane, heat to 82℃, stir and reflux for 9h, wash the reaction solution with deionized water, concentrate the organic phase by rotary evaporation, and obtain hydroxylated triazine containing secondary amine. (2) Add 100g of carbon nanotubes to a mixed solvent of 1200g of deionized water and 250g of anhydrous ethanol, sonicate for 40min, then add 12g of silane coupling agent KH-560, heat to 60℃, stir for 7h, centrifuge, wash three times with deionized water and anhydrous ethanol, and vacuum dry to obtain epoxidized carbon nanotubes. (3) Add 100g of epoxidized carbon nanotubes to 1200g of cyclohexanol, sonicate for 40min, then add 25g of hydroxylated triazine containing secondary amine, heat to 82℃, stir for 7h, centrifuge, wash 3 times with anhydrous ethanol, and vacuum dry to obtain hydroxylated triazine modified carbon nanotubes. (4) Mix 1200g of PET chips (intrinsic viscosity 0.68 dL / g), 95g of flame retardant masterbatch, 70g of hydroxylated triazine modified carbon nanotubes and 32g of color masterbatch, vacuum dry at 140℃ for 3h, and then melt spin through twin screw extrusion (temperature of each zone: zone 1 270℃, zone 2 285℃, zone 3 290℃, winding speed 3500m / min) to obtain modified polyester fiber with 84dtex / 72f; (5) Modified polyester fiber is woven on a 24 needle / cm loom with 58 warp yarns / cm and 42 weft yarns / cm, in 1 / 1 plain weave, to obtain modified polyester fabric. (6) The modified polyester fabric was immersed in an alkali-reducing impregnation solution (containing 9 g / L sodium hydroxide and 4 g / L penetrant JFC-2) at a bath ratio of 1:25, heated to 95°C for 40 min, and then washed with water to obtain the alkali-reducing polyester fabric. (7) The alkali-reduced polyester fabric is subjected to two dips and two nips in a finishing solution (containing 6 g / L surface hardness modifier H-880 and 3 g / L antistatic agent AS-200), and then hot air set at 180℃ for 50 s to obtain an imitation acetate easy-tear fabric.

[0032] Comparative Example 1: The difference between Comparative Example 1 and Example 2 is that the 60g of hydroxylated triazine modified carbon nanotubes in step (4) is replaced with 50g of carbon nanotubes; Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that the 60g of hydroxylated triazine modified carbon nanotubes in step (4) is replaced with 10g of hydroxylated triazine containing secondary amine; Comparative Example 3: The difference between Comparative Example 3 and Example 2 is that the 60g of hydroxylated triazine modified carbon nanotubes in step (4) is replaced with a mixture of 10g triazine and 50g carbon nanotubes; Comparative Example 4: The difference between Comparative Example 4 and Example 2 is that the amount of ethanolamine used in step (1) is adjusted to 3g; Performance testing: Tear strength test: Five specimens (75mm × 150mm) were cut according to GB / T 3917.2-2009. The clamping distance was set to (100±1)mm, the tensile speed was set to 100mm / min, the maximum tear strength was recorded, the arithmetic mean was calculated, and the continuous brittle fracture phenomenon was observed during the tearing process. The results are shown in Table 1.

[0033] Alkali reduction stability test: The bath ratio of the modified polyester fabric in the alkali reduction impregnation solution in the examples and comparative examples was adjusted to 1:20 and 1:30 respectively. The radial tear strength of the prepared imitation acetate easy-tear fabric was tested, and the change rate of warp tear strength of the imitation acetate easy-tear fabric prepared with a bath ratio of 1:25 was calculated. The results are shown in Table 1.

[0034] Data Analysis: As can be seen from the data in Examples 1-3 in Table 1, the acetate-like easy-tear fabric prepared by this invention exhibits excellent stability in the alkali reduction process and an ideal fracture behavior mode. The hydroxylated triazine-modified carbon nanotubes may have constructed a unique microstructure network in the polyester matrix. This network contains both a rigid framework (hard regions) formed by the carbon nanotubes and flexible connecting segments (soft regions) provided by the triazine molecules. This synergistic hard-soft region structure helps to form stress concentration areas in the polyester fiber, promoting the directional propagation of cracks along a predetermined direction, thereby achieving continuous brittle fracture characteristics. The excellent stability in the alkali reduction process can be attributed to the moderating effect of the three-dimensional network structure formed by the hydroxylated triazine-modified carbon nanotubes in the polyester matrix on alkali treatment.

[0035] As can be seen from the data in Example 2 and Comparative Example 1 in Table 1, although the unmodified carbon nanotube system exhibits high initial tear strength, its process stability during alkali reduction is significantly insufficient, with large fluctuations in strength caused by changes in the bath ratio. This indicates that the introduction of hydroxylated triazine may have altered the interaction mechanism at the polyester / carbon nanotube interface. During the modification process, hydroxylated triazine molecules may undergo a ring-opening reaction with the epoxy groups on the surface of carbon nanotubes through secondary amine groups, forming a chemically bonded interfacial layer. This interfacial layer can, on the one hand, improve the uniformity of carbon nanotube dispersion in the polyester matrix, avoiding stress concentration caused by nanotube agglomeration; on the other hand, the hydroxyl groups of the hydroxylated triazine molecules may form a hydrogen bond network with the polyester molecular chains, enhancing the interfacial adhesion between the filler and the matrix. This change in interfacial structure caused by chemical modification may be a key factor in achieving continuous brittle fracture rather than a brittle-ductile mixed fracture, indicating a more uniform stress distribution in the material's microstructure and efficient, directional release of fracture energy.

[0036] As can be seen from the data in Example 2 and Comparative Example 2 in Table 1, the synergistic effect of hydroxylated triazine and carbon nanotubes is crucial to the material properties. Although hydroxylated triazine alone can achieve continuous brittle fracture characteristics, its tear strength and alkali reduction stability are significantly inferior to the hydroxylated triazine-modified carbon nanotube system. This phenomenon indicates that appropriate rigid support structures and flexible connecting networks need to be constructed simultaneously in the polyester matrix to obtain ideal comprehensive properties.

[0037] As can be seen from the data in Table 1 for Example 2 and Comparative Example 3, the chemical bonding mode between hydroxylated triazine and carbon nanotubes has a decisive influence on the final material properties. Although Comparative Example 3 used a physical mixture of the same components, its fracture behavior showed a brittle-ductile mixed fracture, and its alkali reduction stability was significantly poor. This difference indicates that simple physical mixing cannot form a stable functionalized interface layer on the surface of the nanofiller. Chemical bonding modification may have achieved the directional arrangement and uniform distribution of hydroxylated triazine molecules on the surface of carbon nanotubes. This ordered interface structure may more effectively regulate the stress distribution and energy dissipation path in the polyester matrix, resulting in a more consistent fracture behavior in the material.

[0038] As can be seen from the data in Example 2 and Comparative Example 4 in Table 1, the amount of ethanolamine has a significant impact on the structural properties and functional performance of hydroxylated triazine-modified carbon nanotubes. Insufficient ethanolamine may lead to incomplete replacement of chlorine atoms on cyanuric chloride molecules. Appropriate amounts of ethanolamine help form hydroxylated triazine molecules with uniform structure and reasonable functional group density. Although insufficient ethanolamine can still achieve continuous brittle fracture characteristics, its alkali reduction stability is significantly lower than the optimal formulation. This indicates that the molecular structural characteristics of hydroxylated triazine are crucial to its function in the polyester / carbon nanotube composite system. A reasonable molecular structure may more effectively establish a stable interfacial transition layer between the hard region (carbon nanotube framework) and the soft region (polyester molecular chain segments), promoting uniform stress transfer.

Claims

1. A type of acetate-like easy-tear fabric, characterized in that, It is obtained by sequentially weaving, alkali reduction, finishing and heat setting of modified polyester fibers; The preparation steps of the modified polyester fiber are as follows: S1: Add cyanuric chloride and ethanolamine to 1,2-dichloroethane, heat to 78-82℃, stir and reflux for 7-9 hours, wash, and rotary evaporate to obtain hydroxylated triazine containing secondary amine; S2: Add carbon nanotubes to a mixed solvent of deionized water and anhydrous ethanol, disperse by ultrasonication, add silane coupling agent KH-560, heat to 50-60℃, stir for 5-7 hours, centrifuge, wash, and vacuum dry to obtain epoxidized carbon nanotubes. S3: Add epoxidized carbon nanotubes to cyclohexanol, disperse by ultrasonication, then add hydroxylated triazine containing secondary amine, heat to 78-82℃, stir for 5-7 hours, centrifuge, wash, and vacuum dry to obtain hydroxylated triazine modified carbon nanotubes. S4: PET chips, flame retardant masterbatch, hydroxylated triazine modified carbon nanotubes and color masterbatch are mixed, vacuum dried, and then melt-spun through twin-screw extrusion to obtain modified polyester fibers. Preferably, in step S1, the weight ratio of cyanuric chloride, ethanolamine and 1,2-dichloroethane is 10:13-18:80-120; Preferably, in step S2, the weight ratio of carbon nanotubes, deionized water, anhydrous ethanol and silane coupling agent KH-560 is 100:800-1200:150-250:8-12. Preferably, in step S3, the weight ratio of epoxidized carbon nanotubes, cyclohexanol, and hydroxylated triazine containing secondary amine is 100:800-1200:15-25. Preferably, in step S4, the weight ratio of PET chips, flame retardant masterbatch, hydroxylated triazine modified carbon nanotubes, and color masterbatch is 800-1200:65-95:50-70:28-32.

2. The imitation acetate tearable fabric according to claim 1, characterized in that, In step S2, the carbon nanotubes have an outer diameter of 10-20 nm and a length of 0.5-2 μm.

3. The imitation acetate tearable fabric according to claim 1, characterized in that, The intrinsic viscosity of the PET chips in step S4 is 0.65-0.72 dL / g.

4. The imitation acetate tearable fabric according to claim 1, characterized in that, In step S4, the temperatures of each zone in the melt spinning process are: zone 1 260-270℃, zone 2 275-285℃, and zone 3 280-290℃, and the winding speed is 3000-3500m / min.

5. The imitation acetate tearable fabric according to claim 1, characterized in that, The modified polyester fiber in step S4 has a specification of 84 dtex / 72f.

6. A method for preparing an imitation acetate tearable fabric according to any one of claims 1-5, comprising the following steps: (1) Modified polyester fibers are woven on a loom to obtain modified polyester fabric; (2) The modified polyester fabric is immersed in an alkali-reducing impregnation solution with a bath ratio of 1:25, heated to 80-130℃ for 30-40 minutes, and then washed with water to obtain the alkali-reducing polyester fabric. (3) The alkali-reduced polyester fabric is subjected to two dips and two nips in the finishing solution, and then hot air set at 170-180℃ for 40-50s to obtain an imitation acetate easy-tear fabric.

7. The imitation acetate tearable fabric according to claim 6, characterized in that, In step (1), the weaving parameters are 58-75 warp yarns / cm, 22-42 weft yarns / cm, and 1 / 1 plain weave.

8. The imitation acetate tearable fabric according to claim 6, characterized in that, The alkali reduction impregnation solution in step (2) contains 7-9 g / L sodium hydroxide and 2-4 g / L penetrant.

9. The imitation acetate tearable fabric according to claim 6, characterized in that, The finishing solution in step (3) contains 4-6 g / L of surface hardness modifier and 1-3 g / L of antistatic agent.

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