Multifunctional coated cotton fabric and preparation method thereof

Abstract

The invention relates to a multifunctional coated cotton fabric and a preparation method thereof, and belongs to the technical field of functional fabrics. The preparation method comprises the following steps: S1, dissolving pentaerythritol phytate, citric acid and sodium hypophosphite in water to obtain pentaerythritol phytate finishing liquid; carrying out rolling and baking treatment on the cotton fabric by adopting the pentaerythritol phytate finishing liquid to obtain a primarily finished cotton fabric; s2, dissolving chitosan, citric acid and sodium hypophosphite in water to obtain a chitosan finishing solution; carrying out rolling and baking treatment on the primarily finished cotton fabric by adopting chitosan finishing liquid to obtain a secondarily finished cotton fabric; and S3, repeating the operations of S1 to S2 for several times to obtain the multifunctional coated cotton fabric. Phosphate radicals of pentaerythritol phytate serve as an acid source, amino groups of chitosan serve as an air source, sugar rings of chitosan, a polyol structure of pentaerythritol phytate and a carboxyl structure of citric acid serve as carbon sources, and the flame retardant property of the coated cotton fabric is remarkably improved through an intumescent flame retardant mechanism.

Description

Technical Field

[0001] The invention belongs to the technical field of functional fabrics, and in particular relates to a multifunctional coated cotton fabric and a preparation method thereof. Background Art

[0002] Cotton fabrics are widely used in interior decoration, bedding, canvas awning materials and other fields due to their advantages such as moisture absorption, breathability and comfort. However, cotton fabrics are extremely flammable and are flammable textiles. Flame-retardant finishing of cotton fabrics is crucial to reducing fire hazards. As people's requirements for functional textiles become increasingly higher, the development of environmentally friendly and multifunctional flame-retardant finishing systems for textiles is of great significance. Layer-by-layer self-assembly technology mainly deposits flame retardants on the surface of the fabric layer by layer through anionic and cationic electrolytes, thereby improving the flame retardant properties of the fabric. It has the characteristics of high utilization rate and low selectivity for the substrate. However, the electrostatic adsorption and other forces between the assembled layers have defects such as poor durability in ionic detergents.

[0003] Qian Yaowei, Yin Lianbo, Li Jiawei, et al. (Preparation and properties of polyvinylphosphonic acid / polyethylene polyamine layer-by-layer self-assembly flame-retardant cotton fabric [J]. Journal of Textile Research, 2023, 44(9): 144-152.) used polyvinylphosphonic acid and polyethylene polyamine to prepare a flame-retardant coating on the surface of cotton fabric through a layer-by-layer self-assembly method. When 12 layers were arranged, the flame-retardant cotton fabric obtained good flame retardant properties. The process flow was complicated, and polyvinylphosphonic acid and polyethylene polyamine were only deposited on the cotton fabric surface through ionic bonding and could not be combined with the cotton fabric, resulting in poor water resistance.

[0004] Shan Juchuan, Zhao Tianjiao, Li Pan, et al. (Application of electrostatic layer-by-layer self-assembly in flame retardant finishing of cotton fabrics [J]. Printing and Dyeing, 2018, 44(7): 40-44.) successfully assembled ammonium polyphosphate and chitosan onto the surface of cotton fabric for flame retardant finishing by using the electrostatic layer-by-layer self-assembly method. After 20 layers of assembly, the flame retardant properties of the cotton fabric were improved. However, the coating could not bond with the cotton fabric and was deposited on the surface of the cotton fabric only by the ionic bond between the two. It could not bond with the cotton fabric, resulting in poor water resistance.

[0005] Therefore, it is of great significance to use biomass polyelectrolytes to develop environmentally friendly, durable, flame-retardant and antibacterial multifunctional coatings to improve the safety and protective performance of cotton fabrics. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides a multifunctional coated cotton fabric and a preparation method thereof. First, phytic acid and pentaerythritol are reacted to synthesize hydroxyl-rich pentaerythritol phytate. Then, biomass pentaerythritol phytate is used as the anionic component, biomass chitosan is used as the cationic component, and citric acid is used as the cross-linking component. Through layer-by-layer self-assembly treatment, an environmentally friendly, long-lasting, flame-retardant and antibacterial coated cotton fabric is prepared.

[0007] A first object of the present invention is to provide a method for preparing a multifunctional coated cotton fabric, comprising the following steps:

[0008] S1, dissolving pentaerythritol phytate, citric acid and sodium hypophosphite in water to obtain a pentaerythritol phytate finishing solution; and performing a padding and baking treatment on a cotton fabric using the pentaerythritol phytate finishing solution to obtain a primary finished cotton fabric;

[0009] S2, dissolving chitosan, citric acid and sodium hypophosphite in water to obtain a chitosan finishing solution; using the chitosan finishing solution to perform a padding and baking treatment on the primary finished cotton fabric to obtain a secondary finished cotton fabric;

[0010] S3. Repeat the operations of S1-S2 several times to obtain the multifunctional coated cotton fabric.

[0011] In one embodiment of the present invention, in S1, the pentaerythritol phytate is prepared by esterification reaction of phytic acid and pentaerythritol in a molar ratio of 1:(3-3.5); the biomass phytic acid is rich in phosphate and can undergo esterification reaction with the hydroxyl group of pentaerythritol to synthesize hydroxyl-rich pentaerythritol phytate, and the hydroxyl-rich pentaerythritol phytate can participate in the covalent bond cross-linking reaction.

[0012] In one embodiment of the present invention, the esterification reaction temperature is 125° C.-135° C., and the reaction time is 1 h-3 h.

[0013] In one embodiment of the present invention, in S1, the concentration of pentaerythritol phytate in the pentaerythritol phytate finishing solution is 15 g / L-30 g / L, the concentration of citric acid is 30 g / L-50 g / L, and the concentration of sodium hypophosphite is 10 g / L-20 g / L; a high amount of pentaerythritol phytate helps to deposit on the surface of the cotton fabric, but too high an amount is wasteful.

[0014] In one embodiment of the present invention, in S2, the concentration of chitosan in the chitosan finishing liquid is 10g / L-20g / L, the concentration of citric acid is 30g / L-50g / L, and the concentration of sodium hypophosphite is 10g / L-20g / L; a high amount of chitosan helps to deposit on the surface of the cotton fabric, but if the amount is too high, the solution viscosity is high, which can easily cause uneven coating; in addition, chitosan is easily soluble in an aqueous solution of citric acid.

[0015] In one embodiment of the present invention, in S1, the immersion time of the rolling and baking treatment is 5min-10min, the rolling rate is 90%-100%, the drying temperature is 70℃-80℃, the drying time is 2min-3min, the baking temperature is 140℃-150℃, and the baking time is 3min-4min.

[0016] In one embodiment of the present invention, in S2, the chitosan concentration in the chitosan finishing solution is 10 g / L-20 g / L, the citric acid concentration is 30 g / L-50 g / L, and the sodium hypophosphite concentration is 10 g / L-20 g / L.

[0017] In one embodiment of the present invention, in S2, the immersion time of the rolling baking treatment is 5min-10min, the rolling rate is 90%-100%, the drying temperature is 70℃-80℃, the drying time is 2min-3min, the baking temperature is 140℃-150℃, and the baking time is 3min-4min; the higher the rolling rate, the higher the amount of liquid and flame retardant on the cotton fabric, and the better the flame retardant effect, but too high a rate can easily lead to uneven coating; increasing the baking temperature is conducive to the reaction between citric acid and pentaerythritol phytate, chitosan, and cotton fiber, but too high a temperature is wasteful.

[0018] In one embodiment of the present invention, in S1 and S2, citric acid is rich in active carboxyl groups, which can undergo covalent cross-linking reactions with the hydroxyl groups of pentaerythritol phytate and chitosan, and can also undergo covalent cross-linking reactions with the hydroxyl groups of cotton fibers, thereby facilitating the grafting of the flame retardant and antibacterial coating onto the cotton fabric through covalent bonds.

[0019] In one embodiment of the present invention, in S3, the number of repetitions is 2-3; the more the number of repetitions, the more the amount of flame retardant on the surface of the cotton fabric, which is more conducive to flame retardancy, but too high a number is wasteful.

[0020] In one embodiment of the present invention, the weight gain rate of the multifunctional coated cotton fabric is 10.2%-13.8%, so that the coated cotton fabric has good flame retardant properties, antibacterial properties and washability.

[0021] The second object of the present invention is to provide a multifunctional coated cotton fabric prepared by the method.

[0022] In one embodiment of the present invention, the multifunctional coated cotton fabric has a limiting oxygen index of not less than 30.7%, a damaged length of not more than 11.4 cm, and an antibacterial rate against Escherichia coli and Staphylococcus aureus of more than 99.3%; the damaged length after 40 washings is not more than 14.0 cm, and the antibacterial rate against Escherichia coli and Staphylococcus aureus is more than 90.2%, and has excellent flame retardant properties, antibacterial properties and washability.

[0023] The technical solution of the present invention has the following advantages over the prior art:

[0024] (1) The preparation method of the present invention utilizes the ionic bond between the amino groups of chitosan and the phosphate groups of pentaerythritol phytate to form an insoluble flame-retardant antibacterial coating that is deposited on the surface of cotton fabric. Furthermore, the active carboxyl groups of citric acid are used to undergo a covalent cross-linking reaction with the hydroxyl groups of pentaerythritol phytate and chitosan, and also with the hydroxyl groups of cotton fibers, thereby grafting the flame-retardant antibacterial coating onto the cotton fabric via covalent bonds. Therefore, pentaerythritol phytate and chitosan are not only deposited on the surface of the cotton fabric via ionic bonding, but also can be covalently bonded to each other. The resulting deposit can also be bonded to the cotton fabric via covalent bonds, thereby producing a coated cotton fabric with high water resistance.

[0025] (2) The multifunctional coated cotton fabric of the present invention utilizes the phosphate group of pentaerythritol phytate as an acid source, the amino group of chitosan as a gas source, the sugar ring of chitosan and the polyol structure of pentaerythritol phytate and the carboxyl structure of citric acid as carbon sources, thereby significantly improving the flame retardant properties of the coated cotton fabric through an expansion flame retardant mechanism.

[0026] (3) The phytic acid, citric acid and chitosan used in the preparation method of the present invention are all biomass materials, which are environmentally friendly flame retardants and antibacterial agents. The flame retardant and antibacterial coating generated by combining the two has high practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0028] Figure 1 Surface morphology of the coated cotton fabric and the uncoated cotton fabric according to Example 1 of the present invention;

[0029] Figure 2 These are pictures of the vertical burning test of the coated cotton fabric and the uncoated cotton fabric according to Example 1 of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. It should be understood that the specific embodiments are only used to illustrate the present invention and are not intended to limit the present invention.

[0031] In the present invention, unless otherwise defined, technical and scientific terms used herein have the same meanings as commonly understood by one skilled in the art to which the present invention belongs.

[0032] In the present invention, unless stated otherwise, the term "and / or" used in the present invention includes any and all combinations of one or more of the associated listed items.

[0033] In the present invention, unless otherwise stated, the experimental methods used in the examples of the present invention are conventional methods unless otherwise stated, and the materials, reagents, etc. used are all commercially available unless otherwise stated.

[0034] In the present invention, unless otherwise specified, the preparation of pentaerythritol phytate used in the embodiments of the present invention specifically includes the following steps: phytic acid and pentaerythritol are esterified at a molar ratio of 1:3.2 at 130° C. for 2 h to obtain pentaerythritol phytate.

[0035] In the present invention, unless otherwise specified, the padding and baking process used in the embodiments of the present invention is to first immerse the fabric in a finishing solution, then take it out and remove excess water from the fabric using a small padder, and then dry and bake it.

[0036] In the present invention, unless otherwise specified, the cotton fabric used in the embodiments of the present invention is a woven fabric with a gram weight of 150 g / m 2 .

[0037] Example 1

[0038] The multifunctional coated cotton fabric and the preparation method thereof of the present invention specifically comprise the following steps:

[0039] S1, dissolving pentaerythritol phytate, citric acid and sodium hypophosphite in water to obtain a pentaerythritol phytate finishing solution having a pentaerythritol phytate concentration of 22 g / L, a citric acid concentration of 40 g / L and a sodium hypophosphite concentration of 15 g / L; performing a padding and baking treatment on a cotton fabric using the pentaerythritol phytate finishing solution to obtain a primary finished cotton fabric; wherein the padding and baking treatment has an immersion time of 8 min, a padding rate of 95%, a drying temperature of 75° C., a drying time of 2.5 min, a baking temperature of 145° C. and a baking time of 3.5 min;

[0040] S2, chitosan, citric acid and sodium hypophosphite were dissolved in water to obtain a chitosan finishing solution having a chitosan concentration of 15 g / L, a citric acid concentration of 40 g / L and a sodium hypophosphite concentration of 15 g / L; the chitosan finishing solution was used to perform a padding and baking treatment on a primary finishing cotton fabric to obtain a secondary finishing cotton fabric; wherein the padding and baking treatment had an immersion time of 8 min, a padding rate of 95%, a drying temperature of 75 ° C, a drying time of 2.5 min, a baking temperature of 145 ° C, and a baking time of 3.5 min;

[0041] S3. Repeat the operations of S1-S2 three times to obtain a multifunctional coated cotton fabric with a weight gain rate of about 12%.

[0042] Example 2

[0043] The multifunctional coated cotton fabric and the preparation method thereof of the present invention specifically comprise the following steps:

[0044] S1, dissolving pentaerythritol phytate, citric acid and sodium hypophosphite in water to obtain a pentaerythritol phytate finishing solution having a pentaerythritol phytate concentration of 15 g / L, a citric acid concentration of 30 g / L and a sodium hypophosphite concentration of 10 g / L; performing a padding and baking treatment on a cotton fabric using the pentaerythritol phytate finishing solution to obtain a primary finished cotton fabric; wherein the padding and baking treatment comprises an immersion time of 10 min, a padding rate of 100%, a drying temperature of 70° C., a drying time of 3 min, a baking temperature of 140° C. and a baking time of 4 min;

[0045] S2, chitosan, citric acid and sodium hypophosphite were dissolved in water to obtain a chitosan finishing solution having a chitosan concentration of 10 g / L, a citric acid concentration of 30 g / L and a sodium hypophosphite concentration of 10 g / L; the chitosan finishing solution was used to perform a padding and baking treatment on a primary finishing cotton fabric to obtain a secondary finishing cotton fabric; wherein the padding and baking treatment had an immersion time of 10 min, a padding rate of 100%, a drying temperature of 70 ° C, a drying time of 3 min, a baking temperature of 140 ° C, and a baking time of 4 min;

[0046] S3. Repeat the operations of S1-S2 twice to obtain a multifunctional coated cotton fabric with a weight gain rate of about 10.2%.

[0047] Example 3

[0048] The multifunctional coated cotton fabric and the preparation method thereof of the present invention specifically comprise the following steps:

[0049] S1, dissolving pentaerythritol phytate, citric acid and sodium hypophosphite in water to obtain a pentaerythritol phytate finishing solution having a pentaerythritol phytate concentration of 30 g / L, a citric acid concentration of 50 g / L and a sodium hypophosphite concentration of 20 g / L; performing a padding and baking treatment on a cotton fabric using the pentaerythritol phytate finishing solution to obtain a primary finished cotton fabric; wherein the padding and baking treatment comprises an immersion time of 5 min, a padding rate of 90%, a drying temperature of 80° C., a drying time of 2 min, a baking temperature of 150° C. and a baking time of 3 min;

[0050] S2, chitosan, citric acid and sodium hypophosphite were dissolved in water to obtain a chitosan finishing solution having a chitosan concentration of 20 g / L, a citric acid concentration of 50 g / L and a sodium hypophosphite concentration of 20 g / L; the chitosan finishing solution was used to perform a padding and baking treatment on a primary finishing cotton fabric to obtain a secondary finishing cotton fabric; wherein the padding and baking treatment had an immersion time of 5 min, a padding rate of 90%, a drying temperature of 80 ° C, a drying time of 2 min, a baking temperature of 150 ° C, and a baking time of 3 min;

[0051] S3. Repeat the operations of S1-S2 three times to obtain a multifunctional coated cotton fabric with a weight gain rate of about 13.8%.

[0052] Comparative Example 1

[0053] The method is basically the same as Example 1, except that pentaerythritol phytate is replaced by phytic acid.

[0054] Comparative Example 2

[0055] The method is basically the same as Example 1, except that pentaerythritol phytate is replaced by pentaerythritol and phytic acid.

[0056] Comparative Example 3

[0057] The method is basically the same as Example 1, except that pentaerythritol phytate is replaced by triethanolamine phosphate.

[0058] Comparative Example 4

[0059] The method is basically the same as Example 1, except that pentaerythritol phytate finishing liquid is not used.

[0060] Comparative Example 5

[0061] The process is basically the same as Example 1, except that chitosan is replaced by polyethyleneimine.

[0062] Comparative Example 6

[0063] The method is basically the same as Example 1, except that chitosan is replaced by polyhexamethylene biguanide.

[0064] Comparative Example 7

[0065] The method is basically the same as Example 1, except that chitosan finishing liquid is not used for finishing.

[0066] Comparative Example 8

[0067] The process is basically the same as Example 1, except that no citric acid is added to the finishing solutions of S1 and S2.

[0068] Comparative Example 9

[0069] The process is basically the same as Example 1, except that pentaerythritol phytate, chitosan, citric acid and sodium hypophosphite are dissolved in water to obtain a finishing solution.

[0070] Test Example 1

[0071] Based on Example 1, the multifunctional coated cotton fabric (coated cotton fabric) and the untreated cotton fabric (uncoated cotton fabric) were characterized, and the results were as follows: Figure 1 As shown. Figure 1 It can be seen that the surface of the uncoated cotton fabric is smooth and neat, and the functional coating is evenly deposited on the surface of the coated cotton fabric.

[0072] Test Example 2

[0073] The flame retardant properties of the multifunctional coated cotton fabrics (coated cotton fabrics) and untreated cotton fabrics (uncoated cotton fabrics) prepared in Examples 1-3 and Comparative Examples 1-9 were tested:

[0074] Limiting oxygen index (LOI) of fabric: measured in accordance with GB / T 5454-1997 "Textile combustion performance test oxygen index method";

[0075] Fabric damage length: measured in accordance with GB / T 5455-2014 "Fire performance of textiles - Determination of damage length in vertical direction - Smoldering and afterflaming time";

[0076] Antibacterial rate of fabric: measured according to GB / T 20944.3-2008 "Evaluation of antibacterial properties of textiles Part 3: Oscillation method";

[0077] Fabric washing method: Wash according to the standard of AATCC 61-2006 "Accelerated Test for Color Fastness to Washing for Household and Commercial Use".

[0078] Figure 2 Shown are vertical burning images of the coated cotton fabric and the uncoated cotton fabric of Example 1;

[0079] Table 1 shows the relevant properties of the coated cotton fabric and the uncoated cotton fabric finally measured:

[0080] Table 1

[0081]

[0082] From Table 1 and Figure 2 It can be seen that the coated cotton fabric has excellent flame retardant, antibacterial and washable properties.

[0083] By comparing Example 1 and Comparative Example 1, it can be seen that when pentaerythritol phytate is replaced with phytic acid, phytic acid is only combined with chitosan through ionic bonds and is difficult to cross-link with citric acid and cotton fabric, resulting in low deposition efficiency of the functional coating on the cotton fabric surface, reduced functionality of the coated cotton fabric, and poor water washability.

[0084] By comparing Example 1 and Comparative Example 2, it can be seen that when pentaerythritol phytate is replaced with pentaerythritol and phytic acid, phytic acid is difficult to react with citric acid, pentaerythritol, and cotton fabric under baking conditions. Therefore, phytic acid is only combined with chitosan through ionic bonds, resulting in low deposition efficiency of the functional coating on the cotton fabric surface, reduced functionality of the coated cotton fabric, and poor water washability.

[0085] By comparing Example 1 and Comparative Example 3, it can be seen that when pentaerythritol phytate is replaced with triethanolamine phosphate, although triethanolamine phosphate can produce a cross-linking reaction with cotton fabric and chitosan with the help of citric acid, its anionic phosphate content is relatively small, and it is difficult to form a strong ionic bond with cationic chitosan, and it is difficult to produce an insoluble precipitate. The degree of cross-linking through citric acid covalent bonds is limited, resulting in reduced functionality of the coated cotton fabric and poor water washability.

[0086] By comparing Example 1 and Comparative Example 4, it can be seen that when pentaerythritol phytate finishing solution is not used, chitosan is only cross-linked and deposited on the surface of the cotton fabric through the action of citric acid, and an insoluble precipitate cannot be formed. In addition, the degree of cross-linking is limited, resulting in a significant decrease in the flame retardant properties of the coated cotton fabric and a significant decrease in the antibacterial and washable properties.

[0087] By comparing Example 1 and Comparative Example 5, it can be seen that when chitosan is replaced by polyethyleneimine, polyethyleneimine can only be deposited on the surface of the cotton fabric through ionic bonding with pentaerythritol phytate, and it is difficult to produce covalent bonds with pentaerythritol phytate and cotton fabric. In addition, the antibacterial efficiency of polyethyleneimine is low, resulting in a decrease in the antibacterial performance of the coated cotton fabric and a significant decrease in functional durability.

[0088] By comparing Example 1 and Comparative Example 6, it can be seen that when chitosan is replaced with polyhexamethylene biguanide, polyhexamethylene biguanide can only be deposited on the surface of the cotton fabric through ionic bonding with pentaerythritol phytate, and it is difficult to form covalent bonds with pentaerythritol phytate and cotton fabric, resulting in low deposition efficiency of the functional coating on the cotton fabric surface and significantly reduced flame retardant and washable properties of the coated cotton fabric.

[0089] By comparing Example 1 and Comparative Example 7, it can be seen that when chitosan finishing liquid is not used, pentaerythritol phytate is only bonded to the cotton fabric through citric acid covalent bond cross-linking, but the degree of cross-linking is limited, resulting in reduced flame retardant properties of the coated cotton fabric, significantly reduced antibacterial properties, and significantly reduced wash resistance.

[0090] By comparing Example 1 and Comparative Example 8, it can be seen that when citric acid is not added to S1 and S2, pentaerythritol phytate is only combined with chitosan through ionic bonds and is difficult to cross-link with cotton fabric, resulting in low deposition efficiency of the functional coating on the cotton fabric surface, reduced functionality of the coated cotton fabric, and poor wash resistance.

[0091] By comparing Example 1 and Comparative Example 9, it can be seen that when pentaerythritol phytate, chitosan, citric acid and sodium hypophosphite are simultaneously dissolved in water for finishing, the flame retardant properties, antibacterial properties and wash resistance of the coated cotton fabric are all reduced. This is because the anionic pentaerythritol phytate and cationic chitosan will produce ionic bonds in the solution to form a precipitate, making it difficult to uniformly coat the cotton fabric.

[0092] 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 appreciate that other variations or modifications can be made based on the above description. 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 preparing a multifunctional coated cotton fabric, characterized in that: The following steps are involved: S1, dissolving pentaerythritol phytate, citric acid and sodium hypophosphite in water to obtain a pentaerythritol phytate finishing solution; and performing a padding and baking treatment on a cotton fabric using the pentaerythritol phytate finishing solution to obtain a primary finished cotton fabric; S2, dissolving chitosan, citric acid and sodium hypophosphite in water to obtain a chitosan finishing solution; using the chitosan finishing solution to perform a padding and baking treatment on the primary finished cotton fabric to obtain a secondary finished cotton fabric; S3. Repeat the operations of S1-S2 several times to obtain the multifunctional coated cotton fabric.

2. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: In S1, the pentaerythritol phytate is prepared by esterification of phytic acid and pentaerythritol in a molar ratio of 1:(3-3.5).

3. The method for preparing the multifunctional coated cotton fabric according to claim 2, wherein: The temperature of the esterification reaction is 125° C.-135° C., and the time is 1 h-3 h.

4. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: In S1, the concentration of pentaerythritol phytate in the pentaerythritol phytate finishing solution is 15 g / L-30 g / L, the concentration of citric acid is 30 g / L-50 g / L, and the concentration of sodium hypophosphite is 10 g / L-20 g / L.

5. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: In S1, the immersion time of the roll baking treatment is 5 min-10 min, the roll-out rate is 90%-100%, the drying temperature is 70°C-80°C, the drying time is 2 min-3 min, the baking temperature is 140°C-150°C, and the baking time is 3 min-4 min.

6. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: In S2, the chitosan concentration in the chitosan finishing solution is 10 g / L-20 g / L, the citric acid concentration is 30 g / L-50 g / L, and the sodium hypophosphite concentration is 10 g / L-20 g / L.

7. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: In S2, the immersion time of the roll baking treatment is 5 min-10 min, the roll-off rate is 90%-100%, the drying temperature is 70°C-80°C, the drying time is 2 min-3 min, the baking temperature is 140°C-150°C, and the baking time is 3 min-4 min.

8. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: In S3, the number of repetitions is 2-3.

9. The method for preparing the multifunctional coated cotton fabric according to claim 1, wherein: The weight gain rate of the multifunctional coated cotton fabric is 10.2%-13.8%.

10. A multifunctional coated cotton fabric prepared by the method according to any one of claims 1 to 9.

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