Preparation method of durable flame-retardant and smoke-suppressing brocade / cotton blended fabric

Abstract

The present invention relates to a preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric. First, diethylenetriamine pentamethylene phosphonic acid is added to water, and ammonia water is added to adjust the pH value to 5-6 to obtain solution A. Then, an ethanol solution of tetraethyl orthosilicate is dropped into solution A. After the reaction, dicyandiamide is added to obtain a solution containing an anionic phosphorus / nitrogen / silicon flame retardant. Then, the nylon / cotton blended fabric is immersed in the solution containing the anionic phosphorus / nitrogen / silicon flame retardant, and padding and baking treatments are carried out. Next, the treated nylon / cotton blended fabric is immersed in a polyacrylamide solution, and padding and drying treatments are carried out. Finally, the above process of padding the solution containing the anionic phosphorus / nitrogen / silicon flame retardant and the polyacrylamide solution is repeated 2-3 times to obtain the durable flame-retardant and smoke-suppressing nylon / cotton blended fabric. The product prepared by the method of the present invention has excellent flame-retardant and smoke-suppressing properties and wash resistance.

Description

Technical Field

[0001] The present invention belongs to the technical field of flame-retardant nylon / cotton blended fabrics, and relates to a preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric. Background Art

[0002] Nylon / cotton blended fabrics not only have the breathability and comfort of cotton fibers, but also have the advantages of high strength and wear resistance of nylon fibers, so they have a wide range of application prospects. However, due to the "wick effect" during combustion, nylon / cotton blended fabrics are extremely flammable, thus limiting their applications. The durability flame-retardant finishing of nylon / cotton blended fabrics is much more difficult than that of pure cotton and pure nylon fabrics. Simply mixing the durable flame-retardant finishing agents for cotton fabrics and nylon fabrics cannot achieve the flame-retardant effect or the long-lasting flame-retardant effect.

[0003] For example, in Document 1 (Research on Flame Retardancy and Flame Retardant and Water Repellent Composite Finishing of 88 / 12 Cotton-Nylon Blended Fabrics [D]. Donghua University, 2016.), four phosphorus-nitrogen composite flame retardants were compounded to study the durable flame-retardant finishing process of 88 / 12 cotton-nylon blended fabrics; however, the dosage of its flame retardant is very high, and N-hydroxymethyl reaction flame retardants and resin crosslinking agents are used, resulting in potential formaldehyde release in the modified fabrics.

[0004] Chinese invention patent CN116516679A discloses a durable flame-retardant and anti-melting dripping coated nylon 6 fabric and its preparation method, in which polyacrylamide, terephthalaldehyde and DOPO are dissolved in a mixed solution of ethanol and water for reaction to obtain modified polyacrylamide; the modified polyacrylamide is dissolved in a solvent, and the nylon 6 fabric is immersed, and a durable flame-retardant and anti-melting dripping coated nylon 6 fabric is prepared through a padding-baking process. However, the flame retardancy of nylon / cotton blended fabrics is difficult. It is difficult to improve the flame retardant performance of nylon / cotton blended fabrics only through the gas-phase flame retardant mechanism of DOPO flame retardant, and it is difficult to provide long-lasting flame retardant performance only relying on the film-forming property of modified polyacrylamide on the fabric surface.

[0005] Therefore, it is of great significance to study a preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric to solve the problems existing in the prior art. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems existing in the prior art and provide a preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric includes the following steps:

[0009] (1) Add diethylenetriamine pentamethylenephosphonic acid to water, and add ammonia water to adjust the pH value to 5 - 6 (so that part of the phosphate groups of diethylenetriamine pentamethylenephosphonic acid are converted into ammonium phosphate groups, which helps tetraethyl orthosilicate generate silica sol and is conducive to the subsequent covalent bond grafting reaction) to obtain solution A. Then, dropwise add the ethanol solution of tetraethyl orthosilicate into solution A at a rate of 0.5 - 1 mL / min. After the reaction, add dicyandiamide to obtain a solution containing anionic phosphorus / nitrogen / silicon flame retardant; tetraethyl orthosilicate is easily soluble in the ethanol solution. Gradually dropping the ethanol solution of tetraethyl orthosilicate helps to promote the hydrolysis and condensation reaction of tetraethyl orthosilicate after contacting with water to generate silica sol.

[0010] (2) Immerse the nylon / cotton blended fabric into the solution containing anionic phosphorus / nitrogen / silicon flame retardant obtained in step (1), and perform padding and baking treatments.

[0011] (3) Immerse the nylon / cotton blended fabric treated in step (2) into the polyacrylamide solution, and perform padding and drying treatments.

[0012] (4) Repeat steps (2) and (3) 2 - 3 times to prepare a durable flame retardant and smoke suppressing nylon / cotton blended fabric.

[0013] As a preferred technical solution:

[0014] In the preparation method of a durable flame retardant and smoke suppressing nylon / cotton blended fabric as described above, in step (1), based on the solution containing anionic phosphorus / nitrogen / silicon flame retardant, the dosage of diethylenetriamine pentamethylenephosphonic acid is 40 - 60 g / L. Diethylenetriamine pentamethylenephosphonic acid is the main flame retardant component. The higher its dosage, the better the flame retardant performance, but excessive dosage will cause waste. The dosage of tetraethyl orthosilicate is 10 - 20 g / L, and the dosage of dicyandiamide is 20 - 30 g / L.

[0015] In the preparation method of a durable flame retardant and smoke suppressing nylon / cotton blended fabric as described above, in the ethanol solution of tetraethyl orthosilicate in step (1), the mass ratio of tetraethyl orthosilicate to ethanol is 1 - 2:1.

[0016] In the preparation method of a durable flame retardant and smoke suppressing nylon / cotton blended fabric as described above, in step (1), the reaction temperature is 50 - 60 °C, and the reaction time after dropping the ethanol solution of tetraethyl orthosilicate is 2 - 3 h.

[0017] In the preparation method of a durable flame retardant and smoke suppressing nylon / cotton blended fabric as described above, in step (2), the padding is two - dip two - roll, and the liquor pickup is 90 - 110%.

[0018] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric as described above. In step (2), the baking process parameters are: the pre-drying temperature is 70-90°C, the pre-drying time is 2-3 min, the curing temperature is 160-170°C, and the curing time is 3-4 min. A relatively high curing temperature helps to promote the covalent grafting reaction between the phosphate group of diethylenetriamine pentamethylenephosphonic acid in solution A and the hydroxyl group of cotton fibers. However, too high a temperature causes greater damage to the physical properties of the fabric.

[0019] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric as described above. In step (3), the concentration of the polyacrylamide solution is 10-20 g / L.

[0020] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric as described above. In step (3), the padding is two-bath two-roll padding, and the liquor pickup is 90-110%.

[0021] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric as described above. In step (3), the drying temperature is 70-90°C, and the drying time is 2-3 min.

[0022] For a preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric as described in any one of the above, the limiting oxygen index of the durable flame-retardant and smoke-suppressing nylon / cotton blended fabric is not less than 30.5%, the char length is not more than 9.2 cm, and the total smoke release is not more than 0.37 m 2 , and after 40 washes, the char length is still not more than 14.7 cm, meeting the B1 standard (the char length of the unmodified nylon / cotton blended fabric is 30 cm, the limiting oxygen index is 20.3%, and the total smoke release is 0.65 m 2 ).

[0023] The principle of the present invention is:

[0024] The phosphate group of diethylenetriamine pentamethylenephosphonic acid can undergo an esterification cross-linking reaction with the hydroxyl group of cotton fibers under the catalysis of dicyandiamide, thereby grafting a phosphorus-containing flame-retardant group onto the cotton fibers. However, the content of the cotton fiber component in the nylon / cotton blended fabric is limited, making it difficult to graft a sufficient amount of phosphorus-containing flame retardant onto the nylon / cotton blended fabric, unable to provide durable flame-retardant performance, and the use of a single phosphorus-containing flame retardant increases the smoke release of the nylon / cotton blended fabric, increasing the fire hazard.

[0025] In the present invention, the silanol groups formed by the hydrolysis of the siloxane structure of tetraethyl orthosilicate undergo hydrolysis condensation in an aqueous solution to form a network-like silica sol, and the silanol groups can react with the phosphate group of diethylenetriamine pentamethylenephosphonic acid after hydrolysis. Therefore, an anionic phosphorus / nitrogen / silicon flame retardant is formed between the silicon-containing network and diethylenetriamine pentamethylenephosphonic acid ammonium;

[0026] As Figure 1As shown, under the catalysis of dicyandiamide, the phosphate group in the anionic phosphorus / nitrogen / silicon flame retardant can undergo an esterification cross-linking reaction with the hydroxyl groups of cotton fibers; polyacrylamide is a cationic polymer that can form an ionic bond with the anionic phosphorus / nitrogen / silicon flame retardant, and polyacrylamide has good film-forming properties. Its amide structure has good affinity with the amide structure of nylon fibers. Therefore, the polyacrylamide film can be tightly combined with the nylon / cotton blended fabric; thus, the anionic phosphorus / nitrogen / silicon flame retardant and polyacrylamide are deposited on the nylon / cotton blended fabric through ionic bond binding and are combined with the nylon / cotton blended fabric through covalent bonds and supramolecular forces, thereby providing durable flame retardant properties;

[0027] In addition, the phosphate acid in the anionic phosphorus / nitrogen / silicon flame retardant, the amide structure of polyacrylamide, and the silicon-containing flame retardant group improve the flame retardant properties of the nylon / cotton blended fabric through a synergistic flame retardant effect. The flame retardant efficiency is high, and the silicon-containing flame retardant group has the ability to inhibit smoke release. Therefore, the treated nylon / cotton blended fabric has excellent flame retardant and smoke suppression properties.

[0028] Beneficial effects:

[0029] (1) In the preparation method of a durable flame retardant and smoke suppressing nylon / cotton blended fabric of the present invention, the silanol groups formed by the hydrolysis of the siloxane structure of tetraethyl orthosilicate undergo hydrolysis and condensation in an aqueous solution to form a network-like silica sol, and the silanol groups can react with the phosphate groups of diethylenetriamine pentamethylene phosphonic acid after hydrolysis. Therefore, an anionic phosphorus / nitrogen / silicon flame retardant is formed between the silicon-containing network and ammonium diethylenetriamine pentamethylene phosphonate; the anionic phosphorus / nitrogen / silicon flame retardant and polyacrylamide are deposited on the nylon / cotton blended fabric through ionic bond binding and are combined with the nylon / cotton blended fabric through covalent bonds and supramolecular forces, thereby providing durable flame retardant properties;

[0030] (2) In the preparation method of a durable flame retardant and smoke suppressing nylon / cotton blended fabric of the present invention, the phosphate acid in the anionic phosphorus / nitrogen / silicon flame retardant, the amide structure of polyacrylamide, and the silicon-containing flame retardant group improve the flame retardant properties of the nylon / cotton blended fabric through a synergistic flame retardant effect. Therefore, the prepared durable flame retardant and smoke suppressing nylon / cotton blended fabric has excellent flame retardant and smoke suppression properties. Description of the drawings

[0031] Figure 1 It is a schematic diagram of the cross-linking mechanism between the anionic phosphorus / nitrogen / silicon flame retardant and the nylon / cotton blended fabric;

[0032] Figure 2 It is a comparison chart of the smoke release curves of the nylon / cotton blended fabric and the durable flame retardant and smoke suppressing nylon / cotton blended fabric of Example 1 (i.e., the coated nylon / cotton blended fabric in the figure). Detailed implementation manners

[0033] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0034] The test methods for the performance indicators in the embodiments and comparative examples of the present invention are as follows:

[0035] Limiting oxygen index: Tested with reference to the standard of GB / T 5454-1997 "Textiles - Burning performance - Oxygen index method".

[0036] Damage length: Determined with reference to the standard of GB / T 5455-2014 "Textiles - Burning performance - Determination of damage length, afterflame and afterglow time in the vertical direction".

[0037] Total smoke release: Tested and characterized for the total smoke release of the sample using a VOUCH 6810 cone calorimeter with reference to the ISO 5660-1 standard.

[0038] Damage length after 40 washes: First, wash the fabric 40 times with reference to the standard of AATCC 61-2013 "Accelerated test for colorfastness to laundering, home and commercial", and then test the damage length of the fabric with reference to the standard of GB / T 5455-2014 "Textiles - Burning performance - Determination of damage length, afterflame and afterglow time in the vertical direction".

[0039] Example 1

[0040] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric, comprising the following steps:

[0041] (1) Add diethylenetriamine pentamethylene phosphonic acid to water, add ammonia water to adjust the pH value to 5 to obtain solution A, and then dropwise add an ethanol solution of tetraethyl orthosilicate to solution A at a rate of 0.5 mL / min. After reacting at a temperature of 60 °C for 3 h, add dicyandiamide to obtain a solution containing an anionic phosphorus / nitrogen / silicon flame retardant;

[0042] Based on the solution containing the anionic phosphorus / nitrogen / silicon flame retardant, the dosage of diethylenetriamine pentamethylene phosphonic acid is 40 g / L, the dosage of tetraethyl orthosilicate is 10 g / L, and the dosage of dicyandiamide is 20 g / L; in the ethanol solution of tetraethyl orthosilicate, the mass ratio of tetraethyl orthosilicate to ethanol is 1:1;

[0043] (2) Immerse a nylon / cotton blended fabric with a nylon content of 20 wt% into the solution containing the anionic phosphorus / nitrogen / silicon flame retardant obtained in step (1), perform two-bath two-roll padding, control the liquor pickup rate to 90%, and then perform baking treatment;

[0044] The baking process parameters are as follows: the pre-baking temperature is 70°C, the pre-baking time is 3 minutes, the curing temperature is 160°C, and the curing time is 4 minutes.

[0045] (3) Immerse the nylon / cotton blended fabric treated in step (2) into a polyacrylamide solution with a concentration of 10 g / L, perform two-bath two-roll padding, control the liquor pickup rate to be 90%, and then conduct drying treatment at a temperature of 70°C for 3 minutes.

[0046] (4) Repeat step (2) and step (3) twice to obtain a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric.

[0047] The limiting oxygen index of the finally obtained durable flame-retardant and smoke-suppressing nylon / cotton blended fabric is 30.5%, the damaged length is 9.2 cm, and the damaged length after 40 washes is 14.7 cm.

[0048] As Figure 2 shown, the total smoke release amount of the nylon / cotton blended fabric is 0.65 m 2 , and the total smoke release amount of the durable flame-retardant and smoke-suppressing nylon / cotton blended fabric is 0.37 m 2 .

[0049] Comparative Example 1

[0050] A preparation method of a modified nylon / cotton blended fabric is basically the same as that of Example 1, except that in step (1), the ethanol solution of tetraethyl orthosilicate is not added.

[0051] The limiting oxygen index of the finally obtained modified nylon / cotton blended fabric is 29.6%, the damaged length is 10.3 cm, the total smoke release amount is 0.73 m 2 , and the damaged length after 40 washes is 30 cm.

[0052] Comparing Comparative Example 1 with Example 1, it can be found that when tetraethyl orthosilicate is not added, the flame-retardant performance of the modified nylon / cotton blended fabric decreases, the smoke release performance increases, and the wash resistance decreases. This is because the network-like silica sol molecular structure modified by diethylenetriamine pentamethylene phosphonic acid is large, and it combines with polyacrylamide through ionic bonds and deposits on the nylon / cotton blended fabric. Although diethylenetriamine pentamethylene phosphonic acid alone can combine with polyacrylamide through ionic bonds, it still maintains good water solubility, resulting in a decrease in its wash resistance. In addition, the silicon-containing network can generate silicon-containing oxides during the combustion process, which helps to inhibit the generation of smoke.

[0053] Example 2

[0054] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric includes the following steps:

[0055] (1) Add diethylenetriamine pentamethylenephosphonic acid to water, and add ammonia water to adjust the pH value to 5.3 to obtain solution A. Then, dropwise add an ethanol solution of tetraethyl orthosilicate to solution A at a rate of 0.6 mL / min. After reacting at a temperature of 55 °C for 2.8 h, add dicyandiamide to obtain a solution containing an anion phosphorus / nitrogen / silicon flame retardant;

[0056] Based on the solution containing the anion phosphorus / nitrogen / silicon flame retardant, the dosage of diethylenetriamine pentamethylenephosphonic acid is 45 g / L, the dosage of tetraethyl orthosilicate is 13 g / L, and the dosage of dicyandiamide is 24 g / L; in the ethanol solution of tetraethyl orthosilicate, the mass ratio of tetraethyl orthosilicate to ethanol is 1.5:1;

[0057] (2) Immerse a polyamide / cotton blended fabric with a polyamide content of 50 wt% into the solution containing the anion phosphorus / nitrogen / silicon flame retardant obtained in step (1), perform two-bath two-roll padding, control the liquor pickup rate to 95%, and then perform baking treatment;

[0058] The process parameters of baking are: pre-baking temperature 75 °C, pre-baking time 3 min, curing temperature 165 °C, and curing time 3.5 min;

[0059] (3) Immerse the polyamide / cotton blended fabric treated in step (2) into a polyacrylamide solution with a concentration of 13 g / L, perform two-bath two-roll padding, control the liquor pickup rate to 98%, and then perform drying treatment at a temperature of 75 °C for 2.75 min;

[0060] (4) Repeat steps (2) and (3) 2 times to prepare a durable flame-retardant and smoke-suppressing polyamide / cotton blended fabric.

[0061] The limiting oxygen index of the finally prepared durable flame-retardant and smoke-suppressing polyamide / cotton blended fabric is 31.6%, the damage length is 8.6 cm, and the total smoke release is 0.33 m 2 , and the damage length is 13.9 cm after 40 washes.

[0062] Example 3

[0063] A method for preparing a durable flame-retardant and smoke-suppressing polyamide / cotton blended fabric, comprising the following steps:

[0064] (1) Add diethylenetriamine pentamethylenephosphonic acid to water, and add ammonia water to adjust the pH value to 5.5 to obtain solution A. Then, dropwise add an ethanol solution of tetraethyl orthosilicate to solution A at a rate of 0.8 mL / min. After reacting at a temperature of 52 °C for 2.5 h, add dicyandiamide to obtain a solution containing an anion phosphorus / nitrogen / silicon flame retardant;

[0065] Based on the solution containing anionic phosphorus / nitrogen / silicon flame retardant, the dosage of diethylenetriamine pentamethylenephosphonic acid is 50 g / L, the dosage of tetraethyl orthosilicate is 15 g / L, and the dosage of dicyandiamide is 27 g / L; in the ethanol solution of tetraethyl orthosilicate, the mass ratio of tetraethyl orthosilicate to ethanol is 1.8:1;

[0066] (2) Immerse the nylon / cotton blended fabric with 65 wt% nylon content into the solution containing anionic phosphorus / nitrogen / silicon flame retardant obtained in step (1), perform two-bath two-roll padding, control the liquor pickup rate to 100%, and then carry out baking treatment;

[0067] The process parameters of baking are: pre-baking temperature 80 °C, pre-baking time 2.5 min, curing temperature 170 °C, and curing time 3 min;

[0068] (3) Immerse the nylon / cotton blended fabric treated in step (2) into a polyacrylamide solution with a concentration of 18 g / L, perform two-bath two-roll padding, control the liquor pickup rate to 105%, and then carry out drying treatment at a temperature of 80 °C for 2.5 min;

[0069] (4) Repeat steps (2) and (3) three times to obtain a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric.

[0070] The limiting oxygen index of the finally obtained durable flame-retardant and smoke-suppressing nylon / cotton blended fabric is 32.4%, the damaged length is 8.2 cm, and the total smoke release is 0.3 m 2 , and the damaged length is 13.5 cm after 40 washes.

[0071] Example 4

[0072] A preparation method of a durable flame-retardant and smoke-suppressing nylon / cotton blended fabric, comprising the following steps:

[0073] (1) Add diethylenetriamine pentamethylenephosphonic acid to water, add ammonia water to adjust the pH value to 6 to obtain solution A, then dropwise add the ethanol solution of tetraethyl orthosilicate to solution A at a rate of 1 mL / min, react at a temperature of 50 °C for 2 h, and then add dicyandiamide to obtain a solution containing anionic phosphorus / nitrogen / silicon flame retardant;

[0074] Based on the solution containing anionic phosphorus / nitrogen / silicon flame retardant, the dosage of diethylenetriamine pentamethylenephosphonic acid is 60 g / L, the dosage of tetraethyl orthosilicate is 20 g / L, and the dosage of dicyandiamide is 30 g / L; in the ethanol solution of tetraethyl orthosilicate, the mass ratio of tetraethyl orthosilicate to ethanol is 2:1;

[0075] (2) Immerse the nylon / cotton blended fabric with 80 wt% nylon content into the solution containing anionic phosphorus / nitrogen / silicon flame retardant obtained in step (1), perform two-bath two-roll padding, control the liquor pickup rate to 110%, and then carry out baking treatment;

[0076] The technological parameters of baking are as follows: the pre-baking temperature is 90°C, the pre-baking time is 2 min, the curing temperature is 162°C, and the curing time is 3.75 min;

[0077] (3) Immerse the silk / cotton blended fabric treated in step (2) into a polyacrylamide solution with a concentration of 20 g / L, perform two-bath two-roll padding, control the liquor pickup rate to be 110%, and then conduct drying treatment at a temperature of 90°C for 2 min;

[0078] (4) Repeat step (2) and step (3) three times to obtain a durable flame-retardant and smoke-suppressing silk / cotton blended fabric.

[0079] The limiting oxygen index of the finally obtained durable flame-retardant and smoke-suppressing silk / cotton blended fabric is 33.1%, the char length is 7.9 cm, and the total smoke release is 0.28 m 2 , and the char length is 13 cm after 40 washes.

Claims

1. A method for preparing a durable flame retardant and smoke-suppressing nylon / cotton blended fabric, characterized in that The steps include: (1) adding diethylenetriamine penta(methylenephosphonic acid) to water, and adding ammonia water to adjust the pH value to 5-6 to obtain solution A, then adding tetraethyl orthosilicate ethanol solution to solution A at a rate of 0.5-1 mL / min, and adding dicyandiamide after the reaction to obtain a solution containing anionic phosphorus / nitrogen / silicon flame retardant; The reaction temperature is 50-60°C, and the reaction time after the ethanol solution of tetraethyl orthosilicate is added is 2-3 hours; (2) immersing the nylon / cotton blended fabric into the solution containing the anionic phosphorus / nitrogen / silicon flame retardant obtained in step (1), and performing padding and baking treatments; (3) immersing the nylon / cotton blended fabric treated in step (2) into a polyacrylamide solution, and performing padding and drying treatments; (4) Step (2) and step (3) are repeated 2 to 3 times to obtain a durable flame retardant and smoke suppressant nylon / cotton blended fabric.

2. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 1, characterized in that: In step (1), based on the solution containing anionic phosphorus / nitrogen / silicon flame retardant, the amount of diethylenetriaminepenta(methylenephosphonic acid) is 40-60 g / L, the amount of tetraethyl orthosilicate is 10-20 g / L, and the amount of dicyandiamide is 20-30 g / L.

3. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 1, characterized in that: In the ethanol solution of tetraethyl orthosilicate in step (1), the mass ratio of tetraethyl orthosilicate to ethanol is 1 to 2:

1.

4. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 1, characterized in that: In step (2), the dipping and rolling are performed twice, and the rolling ratio is 90-110%.

5. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 4, characterized in that: The baking process parameters in step (2) are: pre-baking temperature of 70-90° C., pre-baking time of 2-3 min, baking temperature of 160-170° C., and baking time of 3-4 min.

6. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 1, characterized in that: The concentration of the polyacrylamide solution in step (3) is 10-20 g / L.

7. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 6, characterized in that: In step (3), the dipping and rolling are performed twice, and the rolling rate is 90-110%.

8. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to claim 7, characterized in that: In step (3), the drying temperature is 70-90° C. and the drying time is 2-3 min.

9. The method for preparing a durable flame retardant and smoke suppressant nylon / cotton blended fabric according to any one of claims 1 to 8, characterized in that: The limiting oxygen index of durable flame retardant and smoke suppression nylon / cotton blended fabric is not less than 30.5%, the damaged length is not higher than 9.2cm, and the total smoke release is not higher than 0.37m 2 After 40 washes, the damaged length is still no more than 14.7cm.

Images