A method for flame retardant finishing of cuprammonia fabric using barley bran extract

Abstract

The present invention provides a method for flame-retardant finishing of cuprammonia fabric using barley bran extract. The flame-retardant finishing method comprises applying a core-shell flame retardant to the surface of the cuprammonia fabric through a padding process. The core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and a barley bran extract as a core layer. The polyguanidine and sodium alginate are self-assembled. The barley bran used in the present invention is a byproduct of barley processing. Processing the barley bran achieves efficient resource utilization, avoids the use of halogens in traditional flame retardants, and exhibits environmentally friendly properties.

Description

Technical Field

[0001] The invention relates to the technical field of functional fabric finishing, and in particular to flame retardant application of a barley bran extract. Background Art

[0002] In recent years, my country's economy and science and technology have developed rapidly, and people's requirements for the functionality of textile fabrics have continued to increase. Most textile fabrics currently are combustible or flammable fabrics. They have disadvantages such as high flammability, high flame spread rate during combustion, and high smoke toxicity. These disadvantages bring huge fire risks and limit the application of polymer materials, which poses a serious threat to people's lives and property safety. At present, the methods for preparing flame-retardant fabrics mainly include copolymerization, blending, composite spinning flame retardant modification, and finishing methods. Among these methods, the finishing method has relatively small restrictions on the thermal stability of flame retardant additives and the size of agglomerated particles. In addition, the process is simple and the cost is low, which can meet different degrees of flame retardancy requirements.

[0003] Halogen flame retardants are widely used due to their low cost and excellent performance, but they can pollute the environment and damage the ecosystem, and are currently being phased out. The use of bio-based resources to produce halogen-free flame retardant additives is becoming a new development trend. Plant-derived flame retardants can significantly suppress smoke and heat release through a cohesive carbonization mechanism, improving material safety.

[0004] Cuprammonia fabric is an environmentally friendly textile made from cuprammonia fibers. Cuprammonia fibers are made from the short fluff of cotton seeds. These fibers are easily decomposed by bacteria in soil and water, do not release toxic gases when burned, and are easily decomposed by waste, making them environmentally friendly. However, cuprammonia fabrics are not flame-retardant and burn easily and quickly in the event of a fire, necessitating flame-retardant finishing. Summary of the Invention

[0005] Technical problem to be solved: The present invention provides a method for flame retardant finishing of cuprammonia fabrics using barley bran extract, and flame retardancy is achieved by loading barley bran extract on the surface of cuprammonia fabrics.

[0006] Technical solution:

[0007] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract. The flame-retardant finishing method comprises loading a core-shell structure flame retardant onto the surface of the cuprammonia fabric through a padding process. The core-shell structure flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer. The polyguanidine and sodium alginate are combined by self-assembly.

[0008] Preferably, the flame retardant finishing method comprises the following steps:

[0009] S1. The core-shell flame retardant is added to water and stirred to obtain a flame retardant finishing liquid;

[0010] S2. Immerse the cuprammonia fabric in the flame retardant finishing solution obtained in S1, perform two immersions and two rollings, and dry to obtain a flame retardant cuprammonia fabric.

[0011] Preferably, the preparation method of the core-shell structure flame retardant in S1 comprises the following steps:

[0012] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 10 to 25 wt %;

[0013] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.1 to 0.8 wt %;

[0014] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.1 to 0.8 wt %;

[0015] S14. Solution C was added to suspension A, stirred for 30 to 60 minutes, and centrifuged to obtain barley bran@polyguanidine;

[0016] S15. Add barley bran@polyguanidine to water to obtain a solution D with a mass fraction of 8 to 10 wt%, add solution B under stirring conditions, and obtain a core-shell structure flame retardant after centrifugal washing.

[0017] Preferably, the mass fraction of the flame retardant finishing liquid in S1 is 20-40 wt%.

[0018] Preferably, the bath ratio of the cuprammonia fabric and the flame retardant finishing liquid in S2 is 1:20-40.

[0019] Preferably, the single dipping time of the double dipping and double rolling in S2 is 40 to 90 seconds, and the rolling rate is 70 to 80%.

[0020] Preferably, the drying temperature in S2 is 100-160° C., and the drying time is 10-30 minutes.

[0021] Preferably, the volume ratio of solution C to suspension A in S14 is 1:1-3.

[0022] Preferably, the volume ratio of solution D to solution B in S15 is 2-3:1-2.

[0023] Preferably, the number of layers of the core-shell structure flame retardant can be controlled by repeating S15 for a number of times.

[0024] Beneficial effects: The present invention has the following advantages:

[0025] 1. The core-shell flame retardant of the present invention uses barley bran extract as the core layer. The barley bran extract contains polyphenols. The polyphenols donate hydrogen atoms from phenolic hydroxyl groups to free radicals through a hydrogen atom transfer mechanism, generating stable substances and phenoxy free radicals. This process disrupts the chain reaction during combustion and prevents oxidation. In addition, the polyphenols can promote the formation of a char layer during pyrolysis. This char layer can act as a barrier to slow the transfer of heat and oxygen into the material, thereby improving the flame retardant properties of the material.

[0026] 2. The core-shell flame retardant of the present invention uses polyguanidine and sodium alginate as the shell layer. Polyguanidine releases non-combustible gases when decomposed by heat. These gases help to block the chain reaction of combustion. Due to their generation and the decomposition of the flame retardant, they absorb most of the heat, greatly reducing the surface temperature of the cuprammonia fabric. In addition, sodium alginate can form a stable carbon layer during combustion. This carbon layer can isolate oxygen and heat, slowing down further combustion of the material, thereby improving the flame retardant properties of the fabric.

[0027] 3. In the present invention, water is used as the assembly medium. The aqueous solution of polyguanidine is positively charged, while the aqueous solution of sodium alginate is negatively charged. Based on the different electrical properties, a flame retardant with a core-shell structure is prepared by layer-by-layer assembly. The number of core layers is controllable, and the core and shell layers work synergistically to improve the flame retardancy of the fabric.

[0028] 4. The barley bran used in the present invention is a by-product of barley processing. The processing of barley bran achieves efficient utilization of resources, avoids the use of halogens in traditional flame retardants, and has environmentally friendly characteristics. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with examples, which are provided to explain the present invention and are not limited to the following examples:

[0030] Example 1

[0031] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0032] Wherein, the flame retardant finishing method comprises the following steps:

[0033] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 20wt%;

[0034] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:20. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 40 seconds, and the rolling rate is 70%. Then, the cuprammonia fabric is dried at 100°C for 10 minutes to obtain a flame-retardant cuprammonia fabric.

[0035] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0036] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 10 wt %;

[0037] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.1 wt %;

[0038] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.1 wt%;

[0039] S14. Solution C was added to suspension A at a volume ratio of 1:1, stirred for 30 min, and centrifuged to obtain barley bran@polyguanidine.

[0040] S15. Barley bran@polyguanidine was added to water to obtain a solution D with a mass fraction of 8 wt%. Solution B was added under stirring at a volume ratio of solution D to solution B of 2:1. After centrifugation and washing, a core-shell flame retardant was obtained.

[0041] Example 2

[0042] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0043] Wherein, the flame retardant finishing method comprises the following steps:

[0044] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 40wt%;

[0045] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:40. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 80%. Then, the cuprammonia fabric is dried at 160°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0046] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0047] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 25 wt %;

[0048] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.8 wt %;

[0049] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0050] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0051] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0052] Example 3

[0053] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0054] Wherein, the flame retardant finishing method comprises the following steps:

[0055] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 25wt%;

[0056] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:30. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 75%. Then, the cuprammonia fabric is dried at 140°C for 20 minutes to obtain a flame-retardant cuprammonia fabric.

[0057] After the impregnation is completed, the copper-ammonia fabric is baked at 160° C. for 30 minutes to obtain a flame-retardant copper-ammonia fabric.

[0058] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0059] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 25 wt %;

[0060] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.7 wt %;

[0061] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0062] S14. Solution C was added to suspension A at a volume ratio of 1:2, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0063] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring at a volume ratio of 3:1.5. After centrifugation and washing, a core-shell flame retardant was obtained.

[0064] Example 4

[0065] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0066] Wherein, the flame retardant finishing method comprises the following steps:

[0067] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 30wt%;

[0068] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:20. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 50 seconds, and the rolling rate is 80%. Then, the cuprammonia fabric is dried at 160°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0069] After the impregnation is completed, the copper-ammonia fabric is baked at 120° C. for 30 minutes to obtain a flame-retardant copper-ammonia fabric.

[0070] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0071] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 15 wt %;

[0072] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.6 wt %;

[0073] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0074] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0075] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0076] Example 5

[0077] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0078] Wherein, the flame retardant finishing method comprises the following steps:

[0079] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 30wt%;

[0080] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:25. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 60 seconds, and the rolling rate is 80%. Then, the cuprammonia fabric is dried at 160°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0081] After the impregnation is completed, the copper-ammonia fabric is baked at 160° C. for 20 minutes to obtain a flame-retardant copper-ammonia fabric.

[0082] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0083] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 12 wt %;

[0084] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.6 wt %;

[0085] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0086] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 40 min, and centrifuged to obtain barley bran@polyguanidine.

[0087] S15. Barley bran@polyguanidine was added to water to obtain a 9 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0088] Example 6

[0089] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0090] Wherein, the flame retardant finishing method comprises the following steps:

[0091] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 30wt%;

[0092] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:35. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 60 seconds, and the rolling rate is 80%. The cuprammonia fabric is then dried at 160°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0093] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0094] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 25 wt %;

[0095] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.6 wt %;

[0096] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.7 wt%;

[0097] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0098] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0099] Example 7

[0100] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0101] Wherein, the flame retardant finishing method comprises the following steps:

[0102] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 30wt%;

[0103] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:40. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 80%. Then, the cuprammonia fabric is dried at 140°C for 25 minutes to obtain a flame-retardant cuprammonia fabric.

[0104] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0105] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 25 wt %;

[0106] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.2 wt %;

[0107] S13. Polyguanidine was added to water and stirred to obtain a 0.8 wt% solution C;

[0108] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0109] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring at a volume ratio of 2:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0110] Example 8

[0111] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0112] Wherein, the flame retardant finishing method comprises the following steps:

[0113] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 22wt%;

[0114] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:30. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 76%. The cuprammonia fabric is then dried at 150°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0115] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0116] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 25 wt %;

[0117] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.8 wt %;

[0118] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.6 wt %;

[0119] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0120] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0121] Example 9

[0122] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0123] Wherein, the flame retardant finishing method comprises the following steps:

[0124] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 20wt%;

[0125] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:25. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 80%. Then, the cuprammonia fabric is dried at 130°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0126] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0127] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 18 wt %;

[0128] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.8 wt %;

[0129] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.6 wt%;

[0130] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0131] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0132] Example 10

[0133] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract. The flame-retardant finishing method comprises loading a core-shell structure flame retardant onto the surface of the cuprammonia fabric through a padding process. The core-shell structure flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer. The polyguanidine and sodium alginate are combined by self-assembly.

[0134] Wherein, the flame retardant finishing method comprises the following steps:

[0135] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 40wt%;

[0136] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:40. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 77%. Then, the cuprammonia fabric is dried at 120°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0137] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0138] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 25 wt %;

[0139] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.5 wt %;

[0140] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0141] S14. Solution C was added to suspension A at a volume ratio of 1:2, stirred for 40 minutes, and centrifuged to obtain barley bran@polyguanidine.

[0142] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring at a volume ratio of 2:1.5. After centrifugation and washing, a core-shell flame retardant was obtained.

[0143] Example 11

[0144] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0145] Wherein, the flame retardant finishing method comprises the following steps:

[0146] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 32wt%;

[0147] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:35. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 90 seconds, and the rolling rate is 72%. The cuprammonia fabric is then dried at 110°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0148] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0149] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 15 wt %;

[0150] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.2 wt %;

[0151] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0152] S14. Solution C was added to suspension A at a volume ratio of 1:2, stirred for 60 min, and centrifuged to obtain barley bran@polyguanidine.

[0153] S15. Barley bran@polyguanidine was added to water to obtain a 10 wt% solution D. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0154] Example 12

[0155] A method for flame-retardant finishing of cuprammonia fabric using barley bran extract, wherein a core-shell flame retardant is loaded onto the surface of the cuprammonia fabric through a padding process, wherein the core-shell flame retardant comprises polyguanidine and sodium alginate as a shell layer and barley bran extract as a core layer, wherein the polyguanidine and sodium alginate are combined by self-assembly;

[0156] Wherein, the flame retardant finishing method comprises the following steps:

[0157] S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid having a mass fraction of 25wt%;

[0158] S2. Immerse the cuprammonia fabric in the flame-retardant finishing solution obtained in S1. The bath ratio of the cuprammonia fabric to the flame-retardant finishing solution is 1:25. A two-dip and two-roll process is adopted. The single immersion time of the two-dip and two-roll process is 55 seconds, and the rolling rate is 73%. Then, the cuprammonia fabric is dried at 140°C for 30 minutes to obtain a flame-retardant cuprammonia fabric.

[0159] The preparation method of the core-shell flame retardant in S1 comprises the following steps:

[0160] S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 12 wt %;

[0161] S12. Sodium alginate was added to water and stirred to obtain a solution B having a mass fraction of 0.4 wt %;

[0162] S13. Polyguanidine was added to water and stirred to obtain a solution C having a mass fraction of 0.8 wt%;

[0163] S14. Solution C was added to suspension A at a volume ratio of 1:3, stirred for 45 minutes, and centrifuged to obtain barley bran@polyguanidine.

[0164] S15. Barley bran@polyguanidine was added to water to obtain a solution D with a mass fraction of 8 wt%. Solution B was added under stirring in a volume ratio of 3:2. After centrifugation and washing, a core-shell flame retardant was obtained.

[0165] Comparative Example 1

[0166] The difference between this comparative example and Example 12 is that the barley bran extract is directly loaded on the surface of the cuprammonia fabric by using a two-immersion and two-rolling process.

[0167] Comparative Example 2

[0168] The difference between this comparative example and Example 12 is that the sodium alginate and polyguanidine are directly loaded on the surface of the cuprammonia fabric by using a two-dipping and two-padding process.

[0169] Comparative Example 3

[0170] The difference between this comparative example and Example 12 is that the shell layer is ammonium polyphosphate and sodium alginate.

[0171] Comparative Example 4

[0172] The difference between this comparative example and Example 12 is that the surface of the cuprammonia fabric is not subjected to any flame retardant treatment.

[0173] Performance Testing

[0174] The obtained samples were subjected to flame retardant performance tests, including limiting oxygen index test and vertical combustion analysis test.

[0175] Table 1 Flame retardant performance test of Examples 1 to 12 and Comparative Examples 1 to 4

[0176] LOI (%) UL-94 Example 1 32.6 V-0 Example 2 34.4 V-0 Example 3 33.5 V-0 Example 4 32.7 V-0 Example 5 31.9 V-0 Example 6 31.6 V-0 Example 7 32.4 V-0 Example 8 33.3 V-0 Example 9 32.1 V-0 Example 10 33.8 V-0 Example 11 34.2 V-0 Example 12 34.5 V-0 Comparative Example 1 27.6 V-1 Comparative Example 2 26.6 V-1 Comparative Example 3 24.9 V-1 Comparative Example 4 19.3 V-1

[0177] Note:

[0178] 1. LOI test: Tested on a COI index meter according to ASTM D2863 standard, LOI < 22% is flammable, LOI between 22-27% is combustible, LOI between 27-34% is difficult to burn, and LOI > 34% is non-flammable;

[0179] 2. Vertical Burning Analysis: Tested according to ASTM D3801 standard, UL-94 results are classified by burning grade V-0, V-1 or V-2. The V-0 grade indicates the polymer material with the best flame retardancy.

[0180] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for flame retardant finishing of cuprammonia fabrics using barley bran extract, characterized in that: The flame retardant finishing method comprises loading a core-shell structure flame retardant onto the surface of a cuprammonium fabric through a padding process, wherein the core-shell structure flame retardant comprises polyguanidine and sodium alginate as a shell layer and a barley bran extract as a core layer, and the polyguanidine and sodium alginate are combined through self-assembly.

2. The method for flame retardant finishing of cuprammonia fabric using barley bran extract according to claim 1, characterized in that: The method comprises the following steps: S1. The core-shell flame retardant was added to water and stirred to obtain a flame retardant finishing liquid; S2. Immerse the cuprammonium fabric in the flame retardant finishing solution obtained in S1, perform two dipping and two rolling, and dry to obtain a flame retardant cuprammonium fabric.

3. The method for flame retardant finishing of cuprammonia fabric using barley bran extract according to claim 2, characterized in that: The preparation method of the core-shell structure flame retardant in S1 comprises the following steps: S11. The barley bran extract was added to water and ultrasonically dispersed to obtain a suspension A having a mass fraction of 10 to 25 wt%; S12. Sodium alginate was added to water and stirred to obtain a mass fraction of 0.1~0.8wt% solution B; S13 polyguanidine was added to water and stirred to obtain a mass fraction of 0.1 ~ 0.8wt% solution C; S14. Solution C was added to suspension A, stirred for 30 to 60 minutes and centrifuged to obtain barley bran @ polyguanidine; S15. Barley bran@polyguanidine was added to water to obtain a solution D with a mass fraction of 8-10 wt%. Solution B was then added under stirring. After centrifugation and washing, a core-shell flame retardant was obtained.

4. The method for flame retardant finishing of cuprammonia fabric using barley bran extract according to claim 2, characterized in that: The mass fraction of the flame retardant finishing liquid in S1 is 20-40 wt %.

5. The method for flame retardant finishing of cuprammonia fabric using barley bran extract according to claim 2, characterized in that: The bath ratio of the cuprammonia fabric and the flame retardant finishing liquid in S2 is 1:20-40.

6. The method for flame retardant finishing of cuprammonia fabric using barley bran extract according to claim 2, characterized in that: The single dipping time of the double dipping and double rolling in S2 is 40-90 seconds, and the rolling rate is 70-80%.

7. The method for flame retardant finishing of cuprammonia fabric using barley bran extract according to claim 2, characterized in that: The drying temperature in S2 is 100-160° C., and the drying time is 10-30 min.

8. The method for flame retardant finishing of cuprammonia fabrics using barley bran extract according to claim 3, characterized in that: The volume ratio of solution C to suspension A in S14 is 1:1-3.

9. The method for flame retardant finishing of cuprammonia fabrics using barley bran extract according to claim 3, characterized in that: The volume ratio of solution D to solution B in S15 is 2-3:1-2.