Antibacterial flame-retardant nylon fabric and preparation method thereof

Abstract

The invention relates to the technical field of flame retardants, and particularly discloses an antibacterial flame-retardant nylon fabric and a preparation method thereof. Comprising the following steps: pretreating nylon fabric; soaking the pretreated nylon fabric in an antibacterial flame retardant for treatment, and drying after soaking to obtain the antibacterial flame-retardant nylon fabric, the antibacterial flame retardant is prepared from guanidine sulfamate, tannic acid and a solvent. Amino groups in guanidine sulfamate and phenolic hydroxyl groups in tannic acid form a macromolecular net-shaped structure through electrostatic interaction, are wound on the surface of fabric fibers in the fabric dipping process, and generate electrostatic interaction with amino groups on the surface of nylon fabric, so that the antibacterial flame retardant is adsorbed on the surface of the nylon fabric. In the combustion process, guanidine sulfamate in the antibacterial flame retardant acts through a gas-phase flame retardant mechanism; tannic acid plays a role in flame retardance in the form of a carbon source. Meanwhile, due to the synergistic effect of guanidine sulfamate and tannic acid, the nylon fabric is also endowed with a very good antibacterial effect. The preparation method is simple in process and easy for large-scale industrial production.

Description

Technical Field

[0001] The invention belongs to the technical field of flame retardants, and particularly relates to an antibacterial flame retardant nylon fabric and a preparation method thereof. Background Art

[0002] As a polyamide synthetic fiber, nylon has brought a new look to textiles and is also a major breakthrough in the synthetic fiber industry. Nylon fabrics have the advantages of good wear resistance, high breaking strength, and processability, and are widely used in transportation, electronics, military textiles, aerospace, home decoration and other fields. At the same time, with the improvement of living standards, people's requirements for the health and safety of textiles are increasing, so the antibacterial and flame retardant properties of textiles have attracted much attention, but the limiting oxygen index of nylon fabrics is 20-22%, which is a flammable textile and cannot meet the fire protection regulations of the relevant textile industry. Therefore, it is of great significance to prepare antibacterial and flame retardant nylon fabrics.

[0003] Adding antibacterial flame retardants by copolymerization and blending is a common method to give nylon materials properties, but it exposes many problems, such as large addition amount and poor dispersibility, which have a certain impact on the processing technology and performance of nylon materials. For example, Chinese patent CN03774265B discloses a method for preparing antibacterial fibers, which adds antibacterial agents to polymers and prepares antibacterial fibers by melt spinning. The amount of antibacterial agents used is large, the effect is limited, and the mechanical properties are seriously lost. Chinese patent CN107460561A discloses a method for preparing antibacterial flame-retardant polyamide 66 fabrics, which first prepolymerizes flame retardant monomers to obtain flame retardant prepolymers, and then adds them to the polymerization process of polyamide 66 to obtain flame-retardant polyamide 66, which is then subjected to antibacterial treatment. The process of this method is relatively complicated. Chinese patent CN103898744A discloses a method for preparing a halogen-free flame-retardant nylon 66 fabric. First, the fabric is pretreated, and then it is fully impregnated with a nitrogen-phosphorus flame retardant containing PNF, AS and HEDP, and then baked to firmly combine the flame retardant with the fabric, thereby achieving the purpose of flame retardancy and anti-melting dripping. The oxygen index value of the nylon sample after treatment increased from 21.1% to 26.0%. The process of this method is simple, but the flame retardant effect of the nylon 66 fabric in this patent still needs to be further improved. Summary of the invention

[0004] The purpose of the present invention is to provide an antibacterial flame-retardant nylon fabric and a preparation method thereof in view of the above-mentioned deficiencies in the prior art. The antibacterial flame-retardant nylon fabric has good antibacterial effect and excellent flame retardant performance. The antibacterial rate against Escherichia coli and Staphylococcus aureus can be greater than 99.9%, and its limiting oxygen index is 41.7%, which meets the non-flammable standard.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] The first object of the present invention is to provide a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps: pretreating the nylon fabric; immersing the pretreated nylon fabric in an antibacterial flame retardant for treatment, and drying after immersion to obtain the antibacterial flame retardant nylon fabric; the antibacterial flame retardant is prepared from guanidine sulfamate, tannic acid and a solvent.

[0007] Furthermore, the molar concentration of the aminosulfonate guanidine is 0.8 to 1.0 mol / L.

[0008] Furthermore, the molar concentration of the tannic acid is 10 to 15 g / L.

[0009] Furthermore, the solvent is a mixed solvent of deionized water and ethanol, wherein the ethanol content is 20-40%.

[0010] Furthermore, the preparation method of the antibacterial flame retardant is to dissolve guanidine sulfamate in deionized water, add tannic acid after it is completely dissolved, stir evenly, add ethanol, and form the antibacterial flame retardant after sufficient reaction.

[0011] Furthermore, the pretreatment is to immerse the nylon fabric in a sodium hydroxide or sodium carbonate solution with a concentration of 1 to 5 wt% for 20 to 24 hours.

[0012] Furthermore, the nylon fabric is polyamide 6 or polyamide 66.

[0013] Furthermore, the immersion time is 1 to 2 hours; and / or the drying treatment is baking at 90° C. for 15 to 20 minutes.

[0014] The second object of the present invention is to provide an antibacterial and flame-retardant nylon fabric prepared according to the above preparation method.

[0015] Furthermore, the mass of the flame retardant coating of the antibacterial flame retardant nylon fabric is 19-22% of the mass of the antibacterial flame retardant nylon fabric.

[0016] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0017] (1) The preparation of the antibacterial flame-retardant nylon fabric of the present invention is completed in two steps:

[0018] ① Fabric pretreatment: immerse the nylon fabric in sodium hydroxide or sodium carbonate aqueous solution for strong alkali treatment to achieve desizing and impurity removal on the fabric surface;

[0019] ② Antibacterial flame retardant treatment: An antibacterial flame retardant of the present application is prepared with guanidine aminosulfonate and tannic acid as raw materials in a mixed solvent of deionized water and ethanol. The amino group in guanidine aminosulfonate and the phenolic hydroxyl group in tannic acid form a macromolecular network structure through electrostatic action, which is entangled with the surface of the fabric fiber during the fabric impregnation process, and at the same time, it has an electrostatic effect with the amino group on the surface of the nylon fabric, which is conducive to the successful adsorption of the antibacterial flame retardant on the surface of the nylon fabric, thereby preparing antibacterial flame retardant nylon fabric. If the concentration of guanidine sulfamate is too low, the antibacterial effect and flame retardant properties of the fabric will be affected. When the concentration is too high, the fabric will become stiff, affecting the mechanical properties of the fabric. When the content of tannic acid is too high, the fabric will turn yellow. Therefore, the content of tannic acid should not be too high. The content of ethanol in the mixed solvent of deionized water and ethanol needs to be controlled at 20-40%. Guanidine sulfamate and tannic acid will generate precipitation in the water solvent due to electrostatic action. Adding ethanol is conducive to the dissolution of the precipitate. At the same time, during the fabric impregnation and drying process, due to the high hydrophobicity of nylon fabric, the antibacterial flame retardant will be seriously unevenly distributed on the fabric surface. Ethanol evaporates faster than deionized water, which is conducive to the uniform adsorption of the antibacterial flame retardant on the fabric surface. However, the ethanol content should not be too high, due to the water solubility of guanidine sulfamate.

[0020] (2) The nylon fabric is treated with the antibacterial flame retardant prepared by the present invention. With the help of the aminosulfonic acid guanidine in the antibacterial flame retardant, during the combustion process, its amino group is thermally decomposed to produce a large amount of non-combustible gas to reduce the oxygen concentration, hinder the combustion of the fabric, and play a gas phase flame retardant effect. The sulfur group is thermally decomposed to produce sulfur dioxide, capture active free radicals, inhibit the combustion chain reaction, and generate non-combustible gas, thereby diluting oxygen and combustible gas to play a flame retardant effect, mainly playing a role in the gas phase flame retardant mechanism; tannic acid is dehydrated and carbonized during the combustion process, and plays a flame retardant role in the form of a carbon source. At the same time, the molecular structure of aminosulfonic acid guanidine contains amino and guanidine sulfonic acid groups, which can form a protective film on the surface of bacteria or fungi, effectively inhibiting the growth and reproduction of bacterial colonies. Tannic acid can also destroy and inhibit the growth of bacteria. The synergistic effect of the two gives nylon fabric a good antibacterial effect.

[0021] (3) The antibacterial flame-retardant nylon fabric prepared by the present invention has good antibacterial effect and excellent flame-retardant performance. The antibacterial rate against Escherichia coli and Staphylococcus aureus is greater than 99.9%, and its limiting oxygen index is 41.7%, which meets the non-flammable standard.

[0022] (4) The raw materials and preparation process of the antibacterial flame retardant and antibacterial flame retardant nylon fabric of the present invention are simple, low in cost, safe and environmentally friendly, and easy to be mass-produced industrially, with broad market prospects. DETAILED DESCRIPTION

[0023] To make the present invention easier to understand, the present invention is further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the professional terms used below are consistent with the meanings understood by professional and technical personnel in the field; unless otherwise specified, the raw materials and reagents involved in this article can be purchased from the market or prepared by known methods.

[0024] Example 1

[0025] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0026] (1) Pretreatment of nylon 6 fabric

[0027] Prepare 1 mol / L NaOH solution, soak nylon 6 fabric in the solution for 24 hours, then rinse with deionized water several times until the nylon 6 fabric is nearly neutral, and dry at 80°C for use.

[0028] (2) Preparation of antibacterial flame retardant

[0029] 12.49 g of guanidine sulfamate was dissolved in deionized water and stirred until completely dissolved to obtain an antibacterial flame retardant, wherein the concentration of guanidine sulfamate was 0.80 mol / L.

[0030] (3) Preparation of antibacterial flame-retardant nylon 6 fabric

[0031] The nylon 6 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the nylon 6 fabric after the immersion treatment is dried at 90°C.

[0032] Example 2

[0033] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0034] (1) Pretreatment of nylon 6 fabric

[0035] Prepare 1 mol / L NaOH solution, soak nylon 6 fabric in the solution for 24 hours, then rinse with deionized water several times until the nylon 6 fabric is nearly neutral, and dry at 80°C for use.

[0036] (2) Preparation of antibacterial flame retardant

[0037] 1.2 g of tannic acid was dissolved in deionized water and stirred until completely dissolved to obtain an antibacterial flame retardant, wherein the concentration of tannic acid was 12 g / L.

[0038] (3) Preparation of antibacterial flame-retardant nylon 6 fabric

[0039] The nylon 6 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the nylon 6 fabric after the immersion treatment is dried at 90°C.

[0040] Example 3

[0041] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0042] (1) Pretreatment of nylon 6 fabric

[0043] Prepare 1 mol / L NaOH solution, soak nylon 6 fabric in the solution for 24 hours, then rinse with deionized water several times until the nylon 6 fabric is nearly neutral, and dry at 80°C for use.

[0044] (2) Preparation of antibacterial flame retardant

[0045] 12.49 g of guanidine sulfamate was dissolved in deionized water, stirred until completely dissolved, and then tannic acid was added and stirred evenly to obtain an antibacterial flame retardant, wherein the concentration of guanidine sulfamate was 0.80 mol / L and the concentration of tannic acid was 12 g / L.

[0046] (3) Preparation of antibacterial flame-retardant nylon 6 fabric

[0047] The nylon 6 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the nylon 6 fabric after the immersion treatment is dried at 90°C.

[0048] Example 4

[0049] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0050] (1) Pretreatment of nylon 6 fabric

[0051] Prepare 1 mol / L NaOH solution, soak nylon 6 fabric in the solution for 24 hours, then rinse with deionized water several times until the nylon 6 fabric is nearly neutral, and dry at 80°C for use.

[0052] (2) Preparation of antibacterial flame retardant

[0053] 12.49 g of guanidine sulfamate was dissolved in deionized water, stirred until completely dissolved, tannic acid was added, stirred evenly, ethanol was added, and after fully dissolved, an antibacterial flame retardant was obtained, wherein the concentration of guanidine sulfamate was 0.80 mol / L, the concentration of tannic acid was 12 g / L, and the content of ethanol was 30%.

[0054] (3) Preparation of antibacterial flame-retardant nylon 6 fabric

[0055] The nylon 6 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the nylon 6 fabric after the immersion treatment is pre-dried at 90°C.

[0056] Example 5

[0057] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0058] (1) Pretreatment of nylon 66 fabric

[0059] Prepare 1 mol / L NaOH solution, soak nylon 66 fabric in the solution for 24 hours, then rinse with deionized water several times until the nylon 66 fabric is nearly neutral, and dry at 80°C for use.

[0060] (2) Preparation of antibacterial flame retardant

[0061] 12.49 g of guanidine sulfamate was dissolved in deionized water, stirred until completely dissolved, tannic acid was added, stirred evenly, ethanol was added, and after fully dissolved, an antibacterial flame retardant was obtained, wherein the concentration of guanidine sulfamate was 0.80 mol / L, the concentration of tannic acid was 12 g / L, and the content of ethanol was 30%.

[0062] (3) Preparation of antibacterial flame-retardant nylon 66 fabric

[0063] The nylon 66 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the nylon 66 fabric after the immersion treatment is pre-dried at 90°C.

[0064] Example 6

[0065] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0066] (1) Pretreatment of cotton fabric

[0067] Prepare 1 mol / L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse with deionized water several times until the cotton fabric is nearly neutral, and dry at 80°C for later use.

[0068] (2) Preparation of antibacterial flame retardant

[0069] 12.49 g of guanidine sulfamate was dissolved in deionized water, stirred until completely dissolved, tannic acid was added, stirred evenly, ethanol was added, and after fully dissolved, an antibacterial flame retardant was obtained, wherein the concentration of guanidine sulfamate was 0.80 mol / L, the concentration of tannic acid was 12 g / L, and the content of ethanol was 30%.

[0070] (3) Preparation of antibacterial flame-retardant cotton fabrics

[0071] The cotton fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the cotton fabric after the immersion treatment is pre-dried at 90°C.

[0072] Example 7

[0073] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0074] (1) Pretreatment of nylon 6 fabric

[0075] Prepare 1 mol / L NaOH solution, soak nylon 6 fabric in the solution for 24 hours, then rinse with deionized water several times until the fabric is nearly neutral, and dry at 80°C for use.

[0076] (2) Preparation of antibacterial flame retardant

[0077] Guanidine phosphate is dissolved in deionized water, stirred until completely dissolved, tannic acid is added, stirred evenly, ethanol is added, and after fully dissolved, an antibacterial flame retardant is obtained, wherein the concentration of guanidine phosphate is 0.80 mol / L, the concentration of tannic acid is 12 g / L, and the content of ethanol is 30%.

[0078] (3) Preparation of antibacterial flame-retardant nylon 6 fabric

[0079] The nylon 6 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the immersed fabric is pre-dried at 90°C.

[0080] Example 8

[0081] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0082] (1) Pretreatment of nylon 66 fabric

[0083] Prepare 1 mol / L NaOH solution, soak nylon 66 fabric in the solution for 24 hours, then rinse with deionized water several times until the fabric is nearly neutral, and dry at 80°C for use.

[0084] (2) Preparation of antibacterial flame retardant

[0085] Guanidine phosphate is dissolved in deionized water, stirred until completely dissolved, tannic acid is added, stirred evenly, ethanol is added, and after fully dissolved, an antibacterial flame retardant is obtained, wherein the concentration of guanidine phosphate is 0.80 mol / L, the concentration of tannic acid is 12 g / L, and the content of ethanol is 30%.

[0086] (3) Preparation of antibacterial flame-retardant nylon 66 fabric

[0087] The nylon 66 fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the immersed fabric is pre-dried at 90°C.

[0088] Example 9

[0089] This embodiment provides a method for preparing an antibacterial flame-retardant nylon fabric, comprising the following steps:

[0090] (1) Pretreatment of cotton fabric

[0091] Prepare 1 mol / L NaOH solution, soak the cotton fabric in the solution for 24 hours, then rinse with deionized water several times until the cotton fabric is nearly neutral, and dry at 80°C for later use.

[0092] (2) Preparation of antibacterial flame retardant

[0093] Guanidine phosphate is dissolved in deionized water, stirred until completely dissolved, tannic acid is added, stirred evenly, ethanol is added, and after fully dissolved, an antibacterial flame retardant is obtained, wherein the concentration of guanidine phosphate is 0.80 mol / L, the concentration of tannic acid is 12 g / L, and the content of ethanol is 30%.

[0094] (3) Preparation of antibacterial flame-retardant cotton fabrics

[0095] The cotton fabric pretreated in step (1) is immersed in the solution of step (2) for 1 hour; the immersed fabric is pre-dried at 90°C.

[0096] The mass of the antibacterial flame retardant coating of the antibacterial flame retardant nylon fabric prepared in Examples 1 to 9 is 19 to 22% of the mass of the antibacterial flame retardant nylon fabric. The antibacterial flame retardant nylon fabric prepared in Examples 1 to 9 of the present application was tested for limiting oxygen index (LOI:%) and antibacterial performance, and the results are shown in Table 1 below. The test conditions are as follows:

[0097] Limiting oxygen index test: According to GB / T5454 1997 Textile Combustion Performance Determination Oxygen Index Method", the test method is to place the sample under vertical test conditions and test the minimum oxygen concentration (also called limiting oxygen index) that just maintains combustion in an oxygen and nitrogen mixed flow. The sample is clamped on a sample clamp and placed vertically in a combustion tube. In the upward oxygen flow, the upper end of the sample is ignited, its combustion characteristics are observed, and its afterburning time (no more than 2 minutes) or destruction length (no more than 40mm) is compared with the specified limit value. By testing a series of samples in different oxygen concentrations, the minimum oxygen concentration value expressed as the percentage of oxygen to maintain combustion can be measured.

[0098] Droplet performance test: Use the vertical burning method to ignite the nylon fabric with a 4cm long flame for 3 seconds. After removing the flame until the burning is completed, observe whether there are droplets falling, and express the results in words.

[0099] Antibacterial performance test: The antibacterial performance was tested in accordance with GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3: Oscillation method". Staphylococcus aureus and Escherichia coli were selected as standard strains in the experiment. The antibacterial performance of antibacterial flame-retardant nylon fabric was visually evaluated using the plate count method. In the absence of conflict, the above embodiments and features in the embodiments herein can be combined with each other.

[0100] Table 1. Antibacterial flame retardant test results.

[0101]

[0102]

[0103] The above table is the test results. Examples 1 and 2 are antibacterial flame retardant nylon fabrics prepared by using guanidine sulfamate and tannic acid as antibacterial flame retardants respectively. Compared with pure nylon fabric, it is found that the antibacterial property and flame retardant property are significantly improved, and the effect of guanidine sulfamate is significantly better than tannic acid. In Example 3, the two are used to treat nylon fabric in a coordinated manner, and it is found that the effect is not ideal, which is attributed to the precipitation of the two under the action of electrostatics. After the mixed solvent is introduced, it is found that the flame retardant property is significantly improved, and the antibacterial effect is excellent. This conclusion can be drawn from Example 4.

[0104] Based on Example 4, comparative experiments were designed respectively. Examples 5 and 6 respectively tried nylon 66 fabric and cotton fabric on the basis of Example 4. The comparison showed that the system had good antibacterial and flame retardant effects on nylon 6, nylon 66 and cotton fabrics. To further verify the scheme, guanidine sulfamate and other guanidine salts (taking guanidine phosphate as an example) were compared. Examples 7, 8 and 9 were based on Example 4, and nylon 6, nylon 66 and cotton fabrics were treated with guanidine phosphate respectively. The results showed that the antibacterial and flame retardancy of the three were not ideal. The comparative experiment further illustrated that guanidine sulfamate and tannic acid can give the fabric excellent antibacterial and flame retardancy.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing an antibacterial flame-retardant nylon fabric, characterized in that: The following steps are involved: The nylon fabric is pretreated; the pretreated nylon fabric is immersed in an antibacterial flame retardant for treatment, and then dried to obtain the antibacterial flame retardant nylon fabric; the antibacterial flame retardant is prepared from guanidine sulfamate, tannic acid and a solvent.

2. The preparation method according to claim 1, characterized in that The molar concentration of the aminosulfonate guanidine is 0.8-1.0 mol / L.

3. The preparation method according to claim 1, characterized in that The molar concentration of the tannic acid is 10-15 g / L.

4. The preparation method according to claim 1, characterized in that: The solvent is a mixed solvent of deionized water and ethanol, wherein the content of ethanol is 20-40%.

5. The preparation method according to claim 1, characterized in that: The preparation method of the antibacterial flame retardant comprises dissolving guanidine sulfamate in deionized water, adding tannic acid after the guanidine sulfamate is completely dissolved, stirring evenly, adding ethanol, and forming the antibacterial flame retardant after sufficient reaction.

6. The preparation method according to claim 1, characterized in that: The pretreatment is to immerse the nylon fabric in a sodium hydroxide or sodium carbonate solution with a concentration of 1 to 5 wt% for 20 to 24 hours.

7. The preparation method according to claim 1, characterized in that: The nylon fabric is polyamide 6 or polyamide 66.

8. The preparation method according to claim 1, characterized in that: The immersion time is 1 to 2 hours; and / or the drying treatment is baking at 90° C. for 15 to 20 minutes.

9. An antibacterial and flame-retardant nylon fabric prepared by the preparation method according to any one of claims 1 to 8.

10. The antibacterial flame-retardant nylon fabric according to claim 9, characterized in that: The mass of the antibacterial flame retardant coating of the antibacterial flame retardant nylon fabric is 19-22% of the mass of the antibacterial flame retardant nylon fabric.

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