Flame-retardant and negative-oxygen-ion composite lyocell / bamboo fiber health-care fabric

Abstract

A manufacturing process for a flame-retardant and negative-oxygen-ion composite Lyocell / bamboo fiber health-care fabric. A preparation process method for the fabric comprises: firstly, subjecting Lyocell fibers to a pretreatment and a pre-oxidation treatment, and then initiating acrylamide surface graft copolymerization on the surface of the Lyocell fibers by means of a cerium salt; chemically modifying the fibers, which have been subjected to the graft modification treatment, and phosphorylating the fibers by reacting same with diphenyl hypophosphoryl chloride, so as to introduce a phosphorus-containing flame retardant into the surface of the fibers, thereby preparing flame-retardant Lyocell fibers; and finally, performing blending by taking the flame-retardant Lyocell fibers as warp yarns and negative-oxygen-ion bamboo fibers as weft yarns: performing fiber pretreatment, cotton mixing, opening and picking, cotton carding, drawing, roving, spinning, spooling, warping, sizing, healding and weaving forming. The produced fabric has the effects of environmental protection, flame retardance and negative-oxygen-ion health care.

Description

A flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric Technical Field

[0001] The invention belongs to the field of flame-retardant fiber fabrics and relates to a flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric and a process method thereof. Background Art

[0002] In recent years, with growing environmental awareness, regenerated cellulose fibers have gradually replaced various synthetic fibers, occupying an increasingly large proportion in daily life. Their applications have expanded from their original applications in clothing and furniture to include medicine, construction, aerospace, and other fields. Lyocell fiber is a new, environmentally friendly cellulose fiber produced using N-methylmorpholine-N-oxide (NMMO) as a solvent. This solvent has an extremely high recovery rate and can be recycled after use, reducing environmental pollution while conserving resources. Lyocell fiber also offers advantages such as a soft, comfortable feel and excellent breathability. As a new green fiber, it is widely used in various industries, including clothing and home furnishings. However, like many fiber textiles, it is highly flammable and produces large amounts of smoke and high-energy heat when burned, posing a significant threat to human life and property. Consequently, improving the flame retardancy of regenerated cellulose fiber fabrics has garnered widespread attention, and the development of highly effective and durable flame-retardant regenerated cellulose fibers has become a major research topic in the fiber textile industry. However, current flame-retardant modification of fiber fabrics faces the following major challenges: The flame retardants or additives used in flame-retardant fiber fabrics often lose their effectiveness over time or with increasing wash cycles, leading to a decrease in flame retardant performance. Furthermore, many flame retardants, particularly halogenated flame retardants, can pollute the environment, with pollutants remaining in the fabric or even being released into the surrounding environment, significantly impacting the environment. Some flame retardants contain harmful substances, such as chlorine and bromine, which can potentially harm human health, such as causing cancer and damaging the reproductive system. Therefore, developing a flame-retardant Lyocell fiber fabric with a simple process, stable flame retardant properties, and no adverse effects on human health is of great significance to the health and development of both humans and the environment. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and a preparation method thereof.

[0004] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is as follows:

[0005] A flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric is manufactured by co-spinning Lyocell fibers, bamboo fibers, and a phosphorus-containing flame retardant. The phosphorus-containing flame retardant is deposited on the surface of the Lyocell fibers via surface grafting copolymerization. The bamboo fibers are negative oxygen ion bamboo fibers. This fabric exhibits flame retardancy. Vertical combustion tests show an afterflame time of 0 seconds, a burning rate as low as 1.6 mm / s, a char length of 48 mm, and a limiting oxygen index of 45.6%. The fabric also contains negative oxygen ions that are beneficial to human health.

[0006] The present invention develops a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and a preparation method thereof for fiber fabrics, and ultimately obtains a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric with strong flame retardancy and stable chemical properties.

[0007] Compared to traditional flame-retardant modification methods (impregnation and coating), graft copolymerization is an environmentally friendly and effective way to modify the chemical structure of fabric surfaces. It can introduce polymer chains onto the surface without disrupting the overall fabric structure. The strong covalent bond between the grafted polymer chains and the fiber surface imparts excellent fabric durability. Furthermore, the introduction of phosphorus-containing flame retardants in conjunction with chemical modification enhances the fabric's flame retardancy through synergistic flame retardancy with nitrogen. Furthermore, blending this with negative oxygen ion bamboo fiber has resulted in the development of a functional fiber fabric with both flame retardancy and negative oxygen ion properties, which is environmentally friendly.

[0008] Preferably, the flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric is characterized by first immersing the Lyocell fiber in a 5 wt% H2SO4 aqueous solution at 45°C for 30 minutes, then rinsing the fiber with distilled water until the washing solution is neutral, and drying the fiber to a constant weight.

[0009] The Lyocell fiber has a breaking strength of 3.9 cN / dtex, a breaking strength CV of 17.38%, a breaking elongation of 23.28%, a moisture regain of 4.58%, an average length of 37.0 mm, a volume resistivity of 8.3×105 Ω•cm, and a linear density of 1.92 dtex.

[0010] The pH value of the H2SO4 aqueous solution is 1, and the drying conditions are: pre-baking in a constant temperature oven at 80°C for 5 min and baking at 160°C for 3 min.

[0011] Preferably, 30 ml of distilled water is added to a three-necked flask equipped with a constant pressure dropping funnel and a reflux condenser, and the treated Lyocell fiber is placed therein. The pH is adjusted to 2 with nitric acid, and the mixture is deoxidized by purging with nitrogen for 30 minutes under stirring. Then, ammonium cerium nitrate is added to pre-oxidize the fiber.

[0012] Preferably, an aqueous solution of acrylamide is added dropwise, and the mixture is stirred at 45°C for 4 hours under a nitrogen atmosphere. After the reaction, a fiber with a yellow viscous substance on the surface is obtained, which is rinsed with distilled water and dried to a constant weight.

[0013] The concentration of the acrylamide aqueous solution was 40 wt%, and 10 ml was added dropwise.

[0014] Preferably, the treated Lyocell fiber is placed in a three-necked flask filled with tetrahydrofuran, and an appropriate amount of triethylamine is added as an acid-binding agent. A reflux condenser and a dropping funnel are also provided. Diphenylphosphinoyl chloride is placed in the dropping funnel, the air in the funnel is purged, and nitrogen is filled for protection. Subsequently, diphenylphosphinoyl chloride is added dropwise, and the mixture is reacted in an ice bath for 6 hours. The temperature is then raised to 50°C, and after reacting for 4 hours, the fiber is removed, repeatedly rinsed with water, and dried to constant weight to obtain flame-retardant modified Lyocell fiber.

[0015] The ratio of triethylamine to diphenylphosphinoyl chloride is 1:1.

[0016] Preferably, flame-retardant Lyocell fiber is used as warp yarn and negative oxygen ion bamboo fiber is used as weft yarn for blending, and the textile process is as follows: fiber pretreatment → cotton mixing → cotton opening and cleaning → cotton carding → drawing → coarse yarn → spun yarn → winding → warping → sizing → drawing in → weaving to obtain flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric.

[0017] Among them, the breaking strength of negative oxygen ion bamboo fiber is 2.29 cN / dtex, the breaking strength CV is 15.1%, the breaking elongation is 24.2%, the regain is 12.8%, the average length is 37.9 mm, the linear density is 1.31 dtex, and the negative oxygen ion concentration is 1060•cm-3.

[0018] Among them, the flame-retardant Lyocell fiber and the negative oxygen ion bamboo fiber were evenly sprayed with an antistatic agent mixture after pre-loosening and left to stand for more than 12 hours. The mass ratio of the antistatic agent to water in the antistatic agent mixture was 1:30.

[0019] The weaving process is designed with a warp density of 685 threads / 10 cm, a weft density of 433 threads / 10 cm, a width of 330 cm, and a five-three-fly satin weave.

[0020] As a preferred method, thermogravimetric analysis (TG) is used to test the thermal stability of flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabrics. According to the requirements of GB / T5455-1997 "Vertical method for flame retardant performance of textiles", the YG(13)815D-I type (vertical method) fabric flame retardant performance tester is used to test the vertical burning performance of fiber fabrics. According to the requirements of GB / T5455-1997 "Oxygen index method for flame retardant performance of textiles", the ASTMD6413-08 type (oxygen index method) fabric flame retardant performance tester is used to test the burning performance of fiber fabrics to determine the limiting oxygen index value.

[0021] The sample mass in the TG test was 3 mg, the atmosphere was nitrogen, the heating rate was 10 °C / min, and the heating range was 0~800 °C.

[0022] In the limiting oxygen index (LOI) test, a sample is clamped vertically in a transparent combustion tube with an upward flow of oxygen and nitrogen. The upper end of the sample is ignited, and the subsequent combustion phenomenon is observed. The continuous burning time and the distance burned are compared with the specified limit values, and the smoldering time is recorded. The LOI value can be determined by a series of test results at different oxygen concentrations.

[0023] The flame-retardant negative oxygen ion composite fiber fabric prepared by the present invention is composited with flame-retardant Lyocell fiber and negative oxygen ion bamboo fiber. The flame-retardant Lyocell fiber is introduced into an acrylamide intermediate by a graft copolymerization method, and a phosphorus-containing flame retardant is introduced into the intermediate for phosphorylation to obtain phosphorus- and nitrogen-containing synergistic flame-retardant Lyocell fiber. The Lyocell fiber is co-spun with the negative oxygen ion bamboo fiber to improve the flame retardancy of the fabric while enhancing the healthiness of the fabric. The fiber fabric has excellent flame retardancy. The results of the vertical burning test show that the afterflame time is 0 s, the burning speed is as low as 1.6 mm / s, and the carbonization length reaches 48 mm.

[0024] Compared with the prior art, the technical solution of the present invention produces the following beneficial technical effects:

[0025] 1. The present invention provides a flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric. The fabric is composed of acrylamide graft copolymerized / chemically modified flame-retardant Lyocell fiber and negative oxygen ion bamboo fiber. The acrylamide is deposited on the surface of the Lyocell fiber by graft copolymerization, and a phosphorus-containing flame retardant is chemically grafted onto the acrylamide, thereby enhancing the flame retardancy of the fiber. At the same time, the blending of the negative oxygen ion bamboo fiber enhances the healthiness of the fabric.

[0026] 2. The acrylamide graft copolymerization method involves reacting the hydroxyl groups on the cellulose macromolecule with the amino groups on the acrylamide, thereby introducing the acrylamide into the cellulose fibers. Further chemical modification with the introduction of a phosphorus-containing flame retardant enhances the flame retardancy. This method provides a long-lasting flame retardant effect and stable flame retardancy.

[0027] 3. Vertical combustion tests have demonstrated that the flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric provided by the present invention exhibits excellent flame retardancy, with a limiting oxygen index (LOI) of 45.6%. Even after 30 washes, the LOI remains at 39.1%. This demonstrates the excellent flame retardancy of the flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric provided by the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG1 is a flow chart of the manufacturing process of flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric. DETAILED DESCRIPTION

[0029] The following examples further illustrate the flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health-care fabric provided by the present invention and its preparation method. It should be noted that the following examples are intended only to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Based on the above disclosure, non-essential improvements and adjustments made by persons skilled in the art to the present invention for specific implementation remain within the scope of protection of the present invention. Example 1

[0030] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0031] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 40 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0032] The samples were prepared according to the above recipe. The specific steps are as follows:

[0033] (1) First, immerse the Lyocell fiber in a 5 wt% H2SO4 aqueous solution at 45°C for 30 min, then rinse the fiber with distilled water until the washing solution is neutral, and finally dry the fiber to constant weight. In a three-necked flask equipped with a constant pressure dropping funnel and a reflux condenser, add 30 ml of distilled water, place the treated Lyocell fiber, adjust the pH to 2 with nitric acid, deoxidize with nitrogen purge for 30 min under stirring, and then add ammonium cerium nitrate to pre-oxidize the fiber.

[0034] (2) A 40 wt% acrylamide aqueous solution was added dropwise, and the mixture was stirred at 45°C for 4 h under a nitrogen atmosphere. After the reaction, a fiber with a yellow sticky substance on the surface was obtained. The fiber was rinsed with distilled water and dried to a constant weight.

[0035] (3) The treated Lyocell fiber was placed in a three-necked flask filled with tetrahydrofuran, and triethylamine was added as an acid-binding agent. A reflux condenser and a dropping funnel were also provided. Diphenylphosphinoyl chloride was placed in the dropping funnel, and the air in the tube was purged and nitrogen was filled for protection. Subsequently, diphenylphosphinoyl chloride was added dropwise. The ratio of triethylamine to diphenylphosphinoyl chloride was 1:1. The mixture was reacted in an ice bath for 6 h. The temperature was then raised to 50°C. After the reaction for 4 h, the fiber was taken out, repeatedly rinsed with water, and dried to a constant weight to obtain flame-retardant modified Lyocell fiber.

[0036] (4) Flame-retardant Lyocell fiber is used as warp yarn and negative oxygen ion bamboo fiber is used as weft yarn. The textile process is as follows: fiber pretreatment → cotton blending → cotton opening and cleaning → cotton carding → drawing → coarse yarn → spun yarn → winding → warping → sizing → drawing in → weaving and shaping. Example 2

[0037] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0038] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 0 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0039] The sample was prepared according to the above recipe, and the specific steps are as shown in Example 1. Example 3

[0040] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0041] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 10 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0042] The sample was prepared according to the above recipe, and the specific steps are as shown in Example 1. Example 4

[0043] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0044] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 20 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0045] The sample was prepared according to the above recipe, and the specific steps are as shown in Example 1. Example 5

[0046] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0047] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 30 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0048] The sample was prepared according to the above recipe, and the specific steps are as shown in Example 1. Example 6

[0049] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0050] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 50 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0051] The sample was prepared according to the above recipe, and the specific steps are as shown in Example 1. Example 7

[0052] This embodiment provides a flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric and its production process, the formula is as follows:

[0053] Lyocell fiber, 5 wt% H2SO4 aqueous solution, nitric acid, ceric ammonium nitrate, 60 wt% acrylamide aqueous solution, tetrahydrofuran, triethylamine, diphenylphosphoryl chloride, negative oxygen ion bamboo fiber.

[0054] The sample was prepared according to the above recipe, and the specific steps are as shown in Example 1.

[0055] Comparative Example 1

[0056] In this comparative example, the Lyocell fiber without flame retardant modification was used to prepare the Lyocell / bamboo fiber health-care fabric. The specific steps are as follows:

[0057] Lyocell fiber is used as warp yarn and negative oxygen ion bamboo fiber is used as weft yarn for blending. The textile process is as follows: fiber pretreatment → cotton mixing → cotton opening and cleaning → cotton carding → drawing → coarse yarn → spun yarn → winding → warping → sizing → drawing in → weaving and shaping. Example 8

[0058] The samples of Examples 1 to 7 were subjected to TG tests.

[0059]

[0060] It can be seen that with the increase of acrylamide content, the initial decomposition temperature, the decomposition temperature of the maximum weight loss rate, the decomposition termination temperature and the residual carbon amount all increase significantly, indicating that the thermal stability of the fabric increases. This shows that the flame retardant modification of Lyocell fiber by cellulose grafting polyacrylamide and diphenylphosphinoyl chloride can change the pyrolysis process of Lyocell fiber and effectively enhance the flame retardancy of Lyocell fiber.

[0061] The samples of Examples 1 to 7 were subjected to vertical combustion performance test and limiting oxygen index determination.

[0062]

[0063] Acrylamide acts as an intermediate to graft the phosphorus-containing flame retardant onto the fiber surface. Therefore, as the acrylamide concentration increases, the phosphorus-containing flame retardant content on the fiber surface increases, leading to improved flame retardancy and a higher limiting oxygen index. When the acrylamide content is increased to 40 wt% (Examples 1, 6, and 7), the flame retardancy and limiting oxygen index of the fiber fabric do not improve further. This is primarily because at this level of acrylamide, the entire phosphorus-containing flame retardant is grafted onto the fiber surface. Therefore, further increasing the acrylamide content does not significantly improve the flame retardancy of the fabric.

[0064] The products of Example 1 and Comparative Example 1 were subjected to vertical combustion performance test and limiting oxygen index determination.

[0065]

[0066] When ignited in air, the untreated fiber fabric burned rapidly, with an afterburn time of 4 seconds, and no residual char remained. However, after a 30-second ignition test, the treated fiber fabric showed no signs of continued flame combustion even after the ignition source was removed, leaving a large amount of char residue. This demonstrates that the introduction of the flame retardant significantly improves the fiber fabric's fire resistance. Furthermore, its limiting oxygen index (LOI) was significantly increased. Even after 30 water washing cycles, the LOI remained at 39.1%, significantly higher than that of the untreated fiber fabric.

[0067] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric, characterized in that: The fabric includes flame-retardant modified Lyocell fiber and bamboo fiber. Acrylamide is introduced into the surface of the Lyocell fiber through graft copolymerization, and a phosphorus-containing flame retardant is further introduced through phosphorylation. The bamboo fiber is negative oxygen ion bamboo fiber. The composite fabric is co-spun by the flame-retardant Lyocell fiber and the negative oxygen ion bamboo fiber.

2. The flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric according to claim 1, characterized in that: First, immerse the Lyocell fiber in a 4-6 wt% H2SO4 aqueous solution at 40-50°C for 25-35 min, then rinse the fiber with distilled water until the washing solution is neutral, and finally dry the fiber to constant weight.

3. The flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric according to claim 2, characterized in that: In a three-necked flask equipped with a constant pressure dropping funnel and a reflux condenser, add 25-35 ml of distilled water, put in the treated Lyocell fiber, adjust the pH to 1.5-2.5 with nitric acid, purge with nitrogen for deoxidation for 25-35 minutes under stirring, and then add ammonium cerium nitrate to pre-oxidize the fiber.

4. The flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric according to claim 3, characterized in that: A 30-50 wt% acrylamide aqueous solution was added dropwise, and the mixture was stirred at 40-50°C for 3-5 h under nitrogen atmosphere. After the reaction, fibers with yellow viscous substances on the surface were obtained, which were rinsed with distilled water and dried to constant weight.

5. The flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric according to claim 4, characterized in that: The treated Lyocell fiber was placed in a three-necked flask filled with tetrahydrofuran, and triethylamine was added as an acid binding agent. A reflux condenser and a dropping funnel were also provided. Diphenylphosphinoyl chloride was placed in the dropping funnel, the air in the tube was exhausted, and nitrogen was filled for protection. Subsequently, diphenylphosphinoyl chloride was added dropwise. The amount of triethylamine and diphenylphosphinoyl chloride was 1:0.5~1:1.

5. The mixture was reacted in an ice bath for 5~7 h, and then the temperature was raised to 45~55°C. After reacting for 3~5 h, the fiber was taken out, repeatedly rinsed with water, and dried to constant weight to obtain flame-retardant modified Lyocell fiber.

6. The flame retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric according to claim 5, characterized in that: The flame-retardant Lyocell fiber is used as the warp yarn and the negative oxygen ion bamboo fiber is used as the weft yarn for blending. The textile process is as follows: fiber pretreatment → cotton mixing → cotton opening and cleaning → cotton carding → drawing → coarse yarn → spun yarn → winding → warping → sizing → drawing in → weaving to obtain the flame-retardant and negative oxygen ion composite Lyocell / bamboo fiber health care fabric.

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