Quick-dry cooling textile integrating flame retardance, antibiosis, radiation cooling and evaporative cooling as well as preparation and application of quick-dry cooling textile

Abstract

The invention relates to a quick-dry cooling textile integrating flame retardance, antibiosis, radiation cooling and evaporative cooling as well as preparation and application of the quick-dry cooling textile, and belongs to the technical field of functional finishing of textiles. The preparation process is simple, the cost is low, and the prepared textile has good flame retardance, antibiosis, one-way moisture conduction and cooling performance and can be applied to the fields of personal heat management, fire protection, building cooling, antibiosis and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of functional finishing of textiles, and particularly relates to a quick-drying and cooling textile integrating flame retardancy, antibacterial, radiation cooling and evaporative cooling, and the preparation and application thereof. Background Art

[0002] In recent years, global warming and extreme weather events have become more serious due to the accumulation of greenhouse effects caused by rapid industrial development. When exposed to extreme high temperature environments, people are prone to heat exhaustion and related diseases such as heat stress and cardiovascular diseases. Although traditional cooling technologies such as refrigeration, ventilation and air conditioning systems (HAVC) have been widely used indoors, these technologies are obtained at the cost of excessive energy consumption (accounting for 15% of global electricity), which seriously hinders the realization of carbon peak and carbon neutrality goals. In addition, this cooling system will fail under high temperature conditions outdoors. Therefore, it has become a top priority to develop a sustainable and efficient cooling strategy for human development.

[0003] Textiles, as the "second skin of the human body", are considered to be ideal candidates for personal thermal management (PTM) and can dynamically regulate the heat / humidity balance between the body and the environment. In recent years, radiative cooling technology, as a passive heat dissipation process that does not require any energy input and can spontaneously and selectively emit sunlight (wavelength 0.3-2.5 μm) and human infrared radiation (HBIR, wavelength 7-14 μm) to the external environment, is becoming the forefront of PTM environmentally friendly cooling methods. For example, the literature Hierarchical-morphology metafabric for scalable passive daytime radiative cooling [J]. 2021 (373): 692-700 designed a multilayer composite microfiber knitted metafabric in which 500 μm titanium oxide-polylactic acid woven fabric was laminated with polytetrafluoroethylene, which can cool the human body by 4.8 °C compared with cotton-covered fabric. However, due to the use of hydrophobic materials and their unfavorable thickness, cutting-edge passive radiative cooling fabrics lack moisture management capabilities, resulting in skin discomfort and low cooling efficiency during sweating. In addition, the complex and expensive preparation process further limits its application in PTM textiles.

[0004] According to Mie scattering theory, when the wavelength of a material is close to the size of its counterpart (such as fiber diameter or pore size), the material has the ability to strongly scatter electromagnetic waves. The pores of porous coatings can act as highly efficient light scatterers to replace the particles in organic and inorganic light scattering systems to reflect sunlight, thereby achieving the effect of radiative cooling. For example, Hierarchically porous polymer coatings for highly efficient passive daytime radiative cooling [J]. 2018 (362): 315-319 prepared porous polyvinylidene fluoride-co-hexafluoropropylene polymer coatings based on evaporation-induced phase separation technology, and their pore size is comparable to the wavelength of sunlight. However, this type of porous coating is mostly composed of hydrophobic polymers and closed-cell structures. When the heat dissipation capacity of the above materials is insufficient, such as when the ambient temperature is close to or exceeds the skin temperature or the body generates too much heat during strenuous exercise, their cooling effect is insufficient and may even have a negative effect. Therefore, the development of quick-drying cooling textiles should have the advantages of high reflectivity of sunlight, high infrared emissivity of the human body, and efficient sweat conduction and evaporation. However, it is still a huge challenge to coordinately regulate the above-mentioned heat and moisture transfer processes, reduce sweat consumption, and meet the thermal comfort needs of the human body.

[0005] Having a comfortable thermal environment is not only an indispensable need for normal human life, but also plays a vital role in human health. Although the technology of using cooling textiles for personal thermal management (PTM) has developed rapidly in recent years, it is not suitable for special working groups (such as soldiers, firefighters, medical staff, etc.) who need to wear protective clothing to work in harsh environments. They urgently need to prevent fire, bacteria, and physical and chemical injuries. Unfortunately, the integration of multifunctionality is often complicated, which limits their use value. Therefore, the development and preparation technology of flame-retardant, antibacterial, sweat-wicking and moisture-absorbing cooling clothing based on PTM has rarely been reported. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a quick-drying cooling textile that integrates flame retardancy, antibacterial properties, radiation cooling and evaporative cooling, as well as its preparation and application, so as to overcome the defects of cooling textiles in the prior art, such as poor thermal comfort, low cooling efficiency, poor air permeability and moisture permeability, and single function.

[0007] The invention provides a textile composition, which comprises, by weight, 10-22 parts of cellulose acetate, 70-85 parts of solvent, 0-15 parts of phytic acid and 0-3 parts of calcium chloride.

[0008] Preferably, the components include 10-22 parts of cellulose acetate, 70-85 parts of solvent, 5-15 parts of phytic acid, and 0-3 parts of calcium chloride in parts by weight.

[0009] Further preferably, the components include, by weight, 10-22 parts of cellulose acetate, 70-85 parts of solvent, 5-15 parts of phytic acid, and 0.5-3 parts of calcium chloride.

[0010] The phytic acid is a phytic acid aqueous solution with a mass percentage concentration of 30-70%.

[0011] The present invention provides a method for preparing a composition for textiles, comprising method 1, method 2 or method 3:

[0012] The method 1 includes mixing the components to obtain a textile composition;

[0013] The method 2 includes dissolving cellulose acetate in a solvent, adding phytic acid, stirring and mixing, and obtaining a textile composition;

[0014] The method 3 includes dissolving cellulose acetate in a solvent and calcium chloride in phytic acid; and then mixing the two and stirring them to obtain a textile composition.

[0015] The stirring and mixing is 200-2000r / min, and the stirring is 1-8h.

[0016] The present invention provides a functional textile, characterized in that the textile is a substrate surface coated with any of the compositions.

[0017] Preferably, the substrate is a hydrophobic substrate; the hydrophobic substrate includes one or more of nylon, polyester, and polypropylene.

[0018] The present invention provides a method for preparing a functional textile, comprising:

[0019] Any of the compositions is coated on a substrate and allowed to stand to obtain a micro-nano porous coated fabric, which is then dried.

[0020] Preferably, the standing temperature is 20-30° C., the humidity is 80-100%, the standing time is 0.5-5 h, and further the standing time is 1-4 h.

[0021] Preferably, the coating thickness is 20-200 μm.

[0022] The coating is performed by coating the composition onto the fabric in a certain thickness using a knife coater.

[0023] The drying temperature is 50-90°C.

[0024] The present invention provides a composition for any of the above textiles and application of any of the above textiles in the fields of personal thermal management, fire protection, building energy saving and antibacterial.

[0025] The present invention is based on the principle of "like dissolves like". The intrinsic aqueous solution of phytic acid reagent as a hexadentate ligand exhibits extremely strong chelating ability for metal calcium ions and generates a stable PA-calcium ion complex that is not easily hydrolyzed. When in contact with cellulose acetate dissolved in acetone, it is more affinity to acetone with a stronger polarity than water, so water acts as a non-solvent in the mixed solvent (no additional water is required in this process), and phase separation occurs to prepare a micro-nano porous coating, which can effectively reflect sunlight and achieve the effect of radiation cooling.

[0026] The cellulose acetate in the present invention has CH (900-700cm -1 )、CO(1382-1300cm -1 )、COC(1260-1110cm -1 )、C-OH(1239-1030cm -1 ) and phytic acid has P=O (1350-1100cm -1 ) and PO(1100-1050cm -1 ) have strong vibration absorption bonds in the mid-infrared region (MIR), which can synergistically improve the emissivity of the micro-nano porous coating at the atmospheric window, thereby further enhancing the effect of radiation cooling.

[0027] The present invention prepares a phytic acid-calcium ion modified cellulose acetate coating with a micro-nanoporous structure by phase inversion technology, and adopts a scraping method to compound the coating to one side of a hydrophobic fabric. The fabric has spectral selectivity, a high specific surface evaporation layer and a gradual wetting gradient, and the introduction of phytic acid-calcium ion metal chelate gives the coating excellent flame retardant and antibacterial capabilities. The preparation process of the present invention is simple and low in cost. The prepared textile has good flame retardant, antibacterial, unidirectional moisture conduction, cooling and temperature reduction properties, and can be used in personal thermal management, fire protection, building cooling, antibacterial and other fields.

[0028] Beneficial Effects

[0029] The cooling fabric of the present invention has a dual gradient effect of pore size and wettability, which can quickly, directionally and against gravity transfer water from the hydrophobic layer (the macropore side of the hydrophobic fabric) to the hydrophilic layer (the small pore side of the coating). The high specific surface and roughness of the porous structure of the super hydrophilic layer can efficiently absorb and diffuse sweat from the skin, promote the evaporation of sweat from the human skin, and improve the thermal comfort of the human microenvironment. In addition, the synergistic effect between radiative cooling and wicking evaporative cooling can further improve the efficiency of passive cooling.

[0030] The cooling fabric of the present invention exhibits excellent flame retardant properties due to the introduction of phytic acid and calcium ions. When the material is exposed to a combustion environment, the presence of phytic acid and calcium ion chelated water in the material causes the surface of the material to absorb heat, gasify, and rapidly expand and carbonize when it contacts the flame, thereby protecting the internal material. Therefore, compared with a single cellulose acetate coated fabric, the cooling fabric greatly improves the flame retardant efficiency and ensures the safety of the material in a fire situation.

[0031] The cooling fabric of the present invention has a good antibacterial effect. On the one hand, the asymmetric wettability of the fabric can quickly transfer sweat from the hydrophobic layer (close to the skin side) to the hydrophilic side, greatly avoiding the growth of bacteria in a hot and humid environment. On the other hand, the introduction of phytic acid-calcium ion chelate can interfere with the adhesion between cells and cause the cell membrane to lose its function, achieving an antibacterial effect. DETAILED DESCRIPTION

[0032] 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 are not intended 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 fall within the scope limited by the appended claims of the application equally.

[0033] Cellulose acetate (CA, Mw ≈ 30,000, density = 1.3 g / mL, CAS: 9004-35-7) was obtained from Aladdin Reagent Co., Ltd. Phytic acid (PA, Mw = 660, 70% in water, CAS: 83-86-3) was provided by Shanghai MacLean Biochemical Technology Co., Ltd. Acetone (Mw = 58, CAS: 67-64-1) was provided by Sinopharm Chemical Reagent Co., Ltd. Calcium chloride (CaCl2, Mw = 110, CAS: 233-140-8) was provided by Shanghai Lingfeng Reagent Co., Ltd.

[0034] Example 1

[0035] (1) A quick-drying cooling textile that integrates flame retardancy, antibacterial properties, radiation cooling, and evaporative cooling, wherein the base of the cooling textile is a nylon fabric;

[0036] (2) First, 11 g of cellulose acetate was dissolved in 78 g of acetone solution, and then 1 g of calcium chloride was dissolved in 10 g of phytic acid (the mass concentration of the reagent itself was 70%), and the mixture was placed in the above solution and stirred at a speed of 1000 r / min for 4 h to obtain a precursor solution;

[0037] (3) coating the precursor solution onto nylon fabric using a knife coater with a thickness of 100 μm;

[0038] (4) Place the coated fabric in a 25°C, 90% high humidity environment for 2 hours;

[0039] (5) Finally, the prepared coated fabric was placed in a vacuum oven at 60 °C to completely dry to remove acetone and water.

[0040] Example 2

[0041] (1) A quick-drying cooling textile that integrates flame retardancy, antibacterial properties, radiation cooling, and evaporative cooling, wherein the base of the cooling textile is a nylon fabric;

[0042] (2) First, 11 g of cellulose acetate was dissolved in 78 g of acetone solution, and then 11 g of phytic acid was placed in the above solution and stirred at a speed of 1000 r / min for 4 h to obtain a precursor solution;

[0043] (3) coating the precursor solution onto nylon fabric using a knife coater with a thickness of 100 μm;

[0044] (4) Place the coated fabric in a 25°C, 90% high humidity environment for 2 hours;

[0045] (5) Finally, the prepared coated fabric was placed in a vacuum oven at 60 °C to completely dry to remove acetone and water.

[0046] Example 3

[0047] (1) A quick-drying cooling textile that integrates flame retardancy, antibacterial properties, radiation cooling, and evaporative cooling, wherein the base of the cooling textile is a nylon fabric;

[0048] (2) First, 22 g of cellulose acetate was dissolved in 78 g of acetone solution and stirred at 1000 r / min for 4 h to obtain a precursor solution;

[0049] (3) coating the precursor solution onto nylon fabric using a knife coater with a thickness of 100 μm;

[0050] (4) Place the coated fabric in a 25°C, 90% high humidity environment for 2 hours;

[0051] (5) Finally, the prepared coated fabric was placed in a vacuum oven at 60 °C to completely dry to remove acetone and water.

[0052] Comparative Example 1

[0053] Same as Example 1, except that in step (1), the base of the cooling textile is polyester fabric.

[0054] Comparative Example 2

[0055] Same as Example 1, except that in step (1), the base of the cooling textile is a polypropylene fabric.

[0056] Comparative Example 3

[0057] Same as Example 1, except that in step (1), the base of the cooling textile is cotton fabric.

[0058] Comparative Example 4

[0059] Same as Example 1, except that in step (3), the thickness of the porous coating is 25 μm.

[0060] Comparative Example 5

[0061] Same as Example 1, except that in step (3), the thickness of the porous coating is 50 μm.

[0062] Comparative Example 6

[0063] Same as Example 1, except that in step (3), the thickness of the porous coating is 150 μm.

[0064] Comparative Example 7

[0065] Same as Example 2, except that in step (1), the base of the cooling textile is polyester fabric.

[0066] Comparative Example 8

[0067] Same as Example 2, except that in step (1), the base of the cooling textile is a polypropylene fabric.

[0068] Comparative Example 9

[0069] Same as Example 2, except that in step (1), the base of the cooling textile is cotton fabric.

[0070] Comparative Example 10

[0071] Same as Example 2, except that in step (3), the thickness of the porous coating is 25 μm.

[0072] Comparative Example 11

[0073] Same as Example 2, except that in step (3), the thickness of the porous coating is 50 μm.

[0074] Comparative Example 12

[0075] Same as Example 2, except that in step (3), the thickness of the porous coating is 150 μm.

[0076] Comparative Example 13

[0077] Same as Example 3, except that in step (1), the base of the cooling textile is polyester fabric.

[0078] Comparative Example 14

[0079] Same as Example 3, except that in step (1), the base of the cooling textile is a polypropylene fabric.

[0080] Comparative Example 15

[0081] Same as Example 3, except that in step (1), the base of the cooling textile is cotton fabric.

[0082] Comparative Example 16

[0083] Same as Example 3, except that in step (1), the thickness of the porous coating is 25 μm.

[0084] Comparative Example 17

[0085] Same as Example 3, except that in step (1), the thickness of the porous coating is 50 μm.

[0086] Comparative Example 18

[0087] Same as Example 3, except that in step (1), the thickness of the porous coating is 150 μm.

[0088] Effect verification

[0089] The textiles prepared in Examples 1-3 and Comparative Examples 1-18 and the uncoated base fabric were tested for solar reflectivity and mid-infrared emissivity. The specific test method is to use a UV-visible-near infrared spectrophotometer equipped with a diffuse reflection integrating sphere to measure the reflectivity of the textile in the range of 0.3-2.5 μm, and use a Fourier spectrometer to measure the emissivity of the textile in the range of 8-14 μm of the human body mid-infrared wavelength. The test results are shown in Table 1:

[0090] Table 1 Reflectivity and emissivity test of Examples 1-3 and Comparative Examples 1-18 and uncoated fabrics

[0091]

[0092]

[0093] The textiles prepared in Examples 1-3 and Comparative Examples 1-18 and the uncoated base fabric were tested for unidirectional moisture conduction performance using a moisture management tester (MMT) in accordance with the AATCC TM-195 standard. The test results are shown in Table 2:

[0094] Table 2 One-way transmission index of Examples 1-3 and Comparative Examples 1-18 and uncoated fabrics

[0095]

[0096]

[0097] The textiles prepared in Examples 1-3 and Comparative Examples 1-18 and the uncoated base fabric were subjected to the oxygen index performance test of textiles according to GB / T5454-1997. The test results are shown in Table 3:

[0098] Table 3 Limiting oxygen index (LOI) values ​​of Examples 1-3 and Comparative Examples 1-18 and uncoated fabrics

[0099] LOI / % Example 1 32.0 Example 2 28.5 Example 3 23.1 Comparative Example 1 31.8 Comparative Example 2 31.5 Comparative Example 3 30.2 Comparative Example 4 25.8 Comparative Example 5 27.2 Comparative Example 6 33.5 Comparative Example 7 28.4 Comparative Example 8 28.2 Comparative Example 9 26.7 Comparative Example 10 24.9 Comparative Example 11 25.6 Comparative Example 12 28.5 Comparative Example 13 21.0 Comparative Example 14 18.7 Comparative Example 15 18.8 Comparative Example 16 19.3 Comparative Example 17 19.5 Comparative Example 18 19.7 Original nylon fabric in Example 1 22.3 Original polyester fabric in Comparative Example 1 20.7 Original polypropylene fabric in Comparative Example 2 18.6 Original cotton fabric in Comparative Example 3 19.0

[0100] For the textiles prepared in Examples 1-3 and Comparative Examples 1-18 and the uncoated base fabric, the antibacterial effect was evaluated by measuring the antibacterial rates of different fabric samples with reference to GB / T2094.3-2008 "Evaluation of Antibacterial Properties of Textiles Part 3: Oscillation Method" and using Staphylococcus aureus (AATCC6538) and Escherichia coli (8099) as experimental strains. The test results are shown in Table 3:

[0101] Table 3 Antibacterial rate of Examples 1-3 and Comparative Examples 1-18 and uncoated fabrics

[0102]

[0103]

[0104] It can be found from Examples 2-3 that, compared with cellulose acetate coating, the introduction of phytic acid can form a micro-nano porous structure through a phase separation process through the principle of "like dissolves like", which can significantly enhance the solar reflectivity and mid-infrared emissivity (8-14 μm) of the coated textiles, thereby improving the radiation cooling effect. In addition, phytic acid with a phosphorus-rich structure can improve the LOI value (flame retardancy) of textiles through an expansion carbonization mechanism. With the further introduction of calcium ions, the phytic acid-calcium ion chelate formed not only further improves the solar reflectivity and mid-infrared emissivity of the coated textiles, but also greatly improves the flame retardancy.

[0105] From the comparative documents 1-3, it can be found that the phytic acid-calcium ion-cellulose acetate coating exhibits excellent solar reflectivity and mid-infrared emissivity for textiles with different substrates, which is conducive to the enhancement of radiation heat dissipation performance. It is worth noting that since cotton fabric is a hydrophilic substrate, the coated fabric does not have a unidirectional moisture conduction effect, while other hydrophobic coated fabrics all show excellent unidirectional moisture conduction effect.

[0106] It can be found from comparative documents 4-6 that the flame retardant properties of phytic acid-calcium ion-cellulose acetate coated textiles are constantly improving with the increase of coating thickness. However, when the thickness increases from 100μm to 150μm, the radiative cooling and unidirectional moisture conduction properties of the coated textiles are not significantly improved.

[0107] It can be found from comparative documents 7-9 that, compared with phytic acid-calcium ion-cellulose acetate coated fabrics, although the solar reflectivity and mid-infrared emissivity of phytic acid-cellulose acetate coated textiles are reduced, they still have excellent radiative cooling effects and are universally applicable to textiles with different substrates.

[0108] It can be found from comparative documents 10-12 that the flame retardant properties of phytic acid-cellulose acetate coated textiles are constantly improving with the increase of coating thickness. However, compared with phytic acid-calcium ion-cellulose acetate coated fabrics of the same thickness, the flame retardant properties and antibacterial properties are reduced.

[0109] It can be found from comparative documents 13-15 that, compared with the base fabric, the cellulose acetate coating does not undergo phase separation to produce a micro-nanoporous structure, so the solar reflectivity and mid-infrared emissivity of the cellulose acetate coated fabric do not change significantly, and it does not have the ability of radiation cooling.

[0110] It can be found from comparative documents 16-18 that as the coating thickness increases, the cellulose acetate coated fabric still does not have flame retardant and antibacterial effects.

Claims

1. A composition for textiles, characterized in that In terms of weight, the components include: 10-22 parts of cellulose acetate; 70-85 parts of solvent; 0-15 parts of phytic acid; and 0-3 parts of calcium chloride.

2. The textile composition according to claim 1, characterized in that In terms of weight, the components include 10-22 parts of cellulose acetate, 70-85 parts of solvent, 5-15 parts of phytic acid, and 0-3 parts of calcium chloride.

3. The textile composition according to claim 1, characterized in that In terms of weight, the components include 10-22 parts of cellulose acetate, 70-85 parts of solvent, 5-15 parts of phytic acid, and 0.5-3 parts of calcium chloride.

4. A method for preparing a composition for textiles, comprising method 1, method 2 or method 3: The method 1 includes mixing the components to obtain a textile composition; The method 2: dissolving cellulose acetate in a solvent, adding phytic acid, and stirring to mix; The method 3 is as follows: dissolving cellulose acetate in a solvent; dissolving calcium chloride in phytic acid; and then mixing the two and stirring to mix well.

5. A textile, characterized in that: The textile is a substrate surface coated with the composition according to any one of claims 1 to 3.

6. The textile according to claim 5, characterized in that: The substrate is a hydrophobic substrate; the hydrophobic substrate includes one or more of nylon, polyester, and polypropylene.

7. A method for preparing a textile, comprising: The composition according to any one of claims 1 to 3 is coated on a substrate, left to stand, and dried.

8. The preparation method according to claim 7, characterized in that: The standing temperature is 20-30° C., the humidity is 80-100%, and the standing time is 0.5-5 h.

9. The preparation method according to claim 7, characterized in that: The coating thickness is 20-200 μm.

10. Use of the textile composition according to any one of claims 1 to 3 and the textile according to any one of claims 5 to 6 in the fields of personal thermal management, fire protection, building energy saving and antibacterial.

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