A method of manufacturing a radiative cooling fabric material and products thereof

Abstract

The application discloses a manufacturing method of a radiation refrigeration fabric material and a product thereof, and belongs to the technical field of functional materials. The manufacturing method comprises the following steps: dissolving a polymer material in a mixed solvent to form a precursor liquid, and performing electrostatic spinning on the precursor liquid to form nano refrigeration fibers; spraying a nano radiation particle dispersion liquid on surfaces of the nano refrigeration fibers; and sequentially performing twisting, heat setting and weaving to obtain the radiation refrigeration fabric material, wherein the nano radiation particle dispersion liquid contains inorganic nano scattering particles and tetrabutyl titanate. The manufacturing method can control the diameters of the formed nano fibers and the loading amount of the nano particles, so that the nano fibers have passive radiation refrigeration performance and can produce sufficient synergistic effect with the inorganic nano scattering particles, and the prepared fabric material has more superior radiation refrigeration performance.

Description

Technical Field

[0001] This application belongs to the field of functional materials technology, and in particular relates to a method for manufacturing a radiation-cooling fabric material and its products. Background Technology

[0002] Radiative cooling, capable of cooling objects below ambient temperature without consuming energy, is a promising green cooling technology. Research indicates that loading fiber fabrics with micro / nano particles can improve their cooling efficiency, and this efficiency increases with the solid content of the micro / nano particles. Therefore, it is necessary to load micro / nano particles onto the surface of fiber fabrics.

[0003] Currently, related technologies typically involve directly incorporating micro / nano particles into the spinning solution and preparing radiation-cooling fibers via electrospinning. For example, patent application CN 110042564A discloses a method for preparing a radiation-cooling fiber membrane, which effectively improves the radiation-cooling effect by incorporating highly monodisperse radiation particles into the spinning solution and preparing radiation-cooling fibers via electrospinning.

[0004] However, the methods described above generally have the following problems: First, micro-nano particles are prone to causing wear and blockage of electrospinning equipment, resulting in poor prospects for industrial production; second, the allowable amount of micro-nano particles is low, which limits the loading level of micro-nano particles and ultimately leads to unsatisfactory radiation cooling performance of the product fabric. Summary of the Invention

[0005] This application discloses a method for manufacturing a radiation-cooling fabric material and its product, aiming to solve the technical problems of poor industrialization prospects, low micro-nano particle loading, and unsatisfactory radiation-cooling performance of the product fabric in the preparation method described above.

[0006] To achieve the above objectives, the first aspect of this application provides a method for manufacturing a radiation-cooling fabric material. The manufacturing method of this application includes:

[0007] To dissolve the polymer material in a mixed solvent to form a precursor solution;

[0008] The precursor solution was electrospun to obtain nano-cooling fibers;

[0009] The nano-radiation particle dispersion was sprayed onto the surface of the nano-cooling fiber, and then twisted, thermoset, and woven sequentially to obtain a radiation-cooling fabric material.

[0010] The nano-radiation particle dispersion contains inorganic nano-scattering particles and tetrabutyl titanate.

[0011] In the implementation scheme of the first aspect, the polymer material is one of polylactic acid, polyurethane, polyacrylonitrile, polyvinylidene fluoride, polyethylene, and polyacrylonitrile.

[0012] In conjunction with the implementation of the first aspect, the mixed solvent contains a high-boiling-point solvent and a low-boiling-point solvent;

[0013] The high-boiling-point solvent is one of N,N-dimethylformamide and N,N-dimethylacetamide;

[0014] The low-boiling-point solvent is one of acetone, chloroform, and dichloromethane;

[0015] The mass ratio of the high-boiling-point solvent to the low-boiling-point solvent is 1:4.

[0016] In conjunction with the implementation of the first aspect, the mass concentration of the polymer material in the precursor solution is 10-16 wt%.

[0017] In the implementation scheme of the first aspect, during electrospinning, the spinning voltage is 18-24kV, the feed speed is 0.8-1.2mL / h, and the receiving distance is 14-18cm.

[0018] In conjunction with the implementation of the first aspect, the nano-refrigeration fiber has a rod-shaped structure with a diameter of 300-800 nm.

[0019] In conjunction with the implementation scheme of the first aspect, the inorganic nano-scattering particles are one or more of TiO2, SiO2, ZnO, and Si3N2;

[0020] The inorganic nano-scattering particles have a particle size of 100-300 nm.

[0021] In conjunction with the implementation scheme of the first aspect, the mass concentration of inorganic nano-scattering particles in the nano-radiation particle dispersion is 1-4 wt%.

[0022] In the implementation scheme of the first aspect, during the spraying process, the flow rate pressure is 0.3-0.5 MPa and the receiving distance is 5-10 cm.

[0023] The second aspect of this application provides a radiation-cooling fabric material produced by the manufacturing method of this application. The radiation-cooling fabric material of this application contains nanofibers for cooling and inorganic nano-scattering particles loaded on the surface of the nanofibers. The loading amount of the inorganic nano-scattering particles on the surface of the nanofibers is 30-45%.

[0024] Compared with the prior art, the advantages or beneficial effects of the embodiments of this application include at least the following:

[0025] The manufacturing method provided in the first aspect of this application, through a combination of related steps, can, on the one hand, control the morphology and diameter of the formed nanofibers so that the diameter of the nanofibers is comparable to the wavelength of visible light, thereby endowing the nanofibers with the ability to scatter sunlight and enabling them to possess radiative cooling properties; on the other hand, it can effectively increase the loading of inorganic nano-scattering particles and enhance the adhesion between inorganic nano-scattering particles and nano-cooling fibers, effectively avoiding the problem of inorganic nano-scattering particles falling off, and enabling a sufficient synergistic effect between nano-cooling fibers and inorganic nano-scattering particles, thereby significantly improving the cooling effect of the fabric material and extending the effective period of the cooling effect; thirdly, it can effectively remove the limitation of the loading of inorganic nano-scattering particles, allowing the loading of inorganic nano-scattering particles to reach a very high level without causing equipment wear and blockage, showing good prospects for industrial production.

[0026] The radiation cooling fabric material provided in the second aspect of this application, based on the manufacturing method described above, can effectively control the morphology and diameter of the formed fibers and increase the solid content of the inorganic nano-scattering particles, so that the nano-cooling fibers and inorganic nano-scattering particles can produce a full synergistic effect, thereby ensuring that the radiation cooling fabric material has high and long-lasting radiation cooling performance and can be industrially produced at low cost.

[0027] The test results of the examples show that the radiation cooling fabric material prepared in this application has a reflectivity of 92-95% in the visible light band, an atmospheric window emissivity of 93-94%, and an average cooling range of 6.2℃, exhibiting excellent radiation cooling effect. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 SEM image of the nano-refrigeration fiber F1 provided in the embodiments of this application;

[0030] Figure 2 SEM image of rcM1, a radiation-cooling fabric material provided in the embodiments of this application;

[0031] Figure 3 The ultraviolet-visible-near-infrared reflectance curve of the radiation-cooling fabric material rcM1 provided in the embodiments of this application;

[0032] Figure 4 Emissivity curves of the radiative cooling fabric material rcM1 in the atmospheric window band provided in the embodiments of this application;

[0033] Figure 5 The ultraviolet-visible-near-infrared reflectance curves of radiation-cooled fabric material rcM1 and radiation-cooled fabric material rcM7 provided in the embodiments of this application;

[0034] Figure 6 This is a comparison diagram of the cooling effect of the radiative cooling fabric material rcM1 provided in the embodiments of this application with that of different materials;

[0035] Figure 7 The image shows the cooling effect of the radiative cooling fabric material rcM1 provided in the embodiments of this application in an outdoor environment. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0037] In the following description of this embodiment, the term "and / or" is used to describe the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, B existing alone, and A and B existing simultaneously. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0038] In the following description of this embodiment, the term "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0039] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms "a" and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0040] Those skilled in the art should understand that in the following description of the embodiments of this application, the sequence of numbers does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0041] Those skilled in the art will understand that the numerical ranges in the embodiments of this application should be understood to specifically disclose each intermediate value between the upper and lower limits of the range. Each smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included within the scope of this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0042] Unless otherwise stated, the technical / scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. While this application describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this application. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0043] In a first aspect, embodiments of this application provide a method for manufacturing a radiation-cooling fabric material. The manufacturing method of this application includes:

[0044] To dissolve the polymer material in a mixed solvent to form a precursor solution;

[0045] The precursor solution was electrospinned to obtain nano-cooling fibers.

[0046] The dispersion of nano-radiation particles was sprayed onto the surface of nano-cooling fibers, and then twisted, thermoset, and woven sequentially to obtain radiation-cooling fabric material.

[0047] The nano-radiation particle dispersion contains inorganic nano-scattering particles and tetrabutyl titanate.

[0048] The manufacturing method provided in this application, through the combination of the above steps, can, on the one hand, control the morphology and diameter of the formed nanofibers so that the diameter of the nanofibers is comparable to the wavelength of visible light, thereby endowing the nanofibers with the ability to scatter sunlight and enabling them to possess radiative cooling properties; on the other hand, it can effectively increase the loading of inorganic nano-scattering particles and enhance the adhesion between inorganic nano-scattering particles and nanofibers, effectively avoiding the problem of inorganic nano-scattering particles falling off, and enabling a sufficient synergistic effect between nanofibers and inorganic nano-scattering particles, thereby significantly improving the cooling effect of the fabric material and extending the effective period of the cooling effect; thirdly, it can effectively remove the limitation of the loading of inorganic nano-scattering particles, so that no equipment wear and blockage problems occur when the loading of inorganic nano-scattering particles reaches a very high level, which has good prospects for industrial production. The technical principle of the manufacturing method in this application is as follows: First, the polymer material is dissolved in a mixed solvent and electrospun into fibers. This process has several advantages: First, it controls the morphology and structure of the formed fibers, making them rod-shaped, which facilitates subsequent weaving and endows the nanofibers with the ability to scatter solar light waves. Second, it allows direct control of the nanofiber diameter, keeping it within the range of 300-800 nm, thereby reducing the solar heat gain effect and achieving the preparation of nanofibers with radiative cooling properties. Second, the nano-radiative particle dispersion is sprayed onto the surface of the nano-cooling fibers. This process increases the loading of inorganic nano-scattering particles on the surface of the nano-cooling fibers and achieves uniform distribution, resulting in a synergistic effect between the nano-cooling fibers and inorganic nano-scattering particles, improving the cooling effect of the fabric material. Third, it enhances the adhesion between inorganic nano-scattering particles and the surface of the nano-cooling fibers, preventing the inorganic nano-scattering particles from falling off and achieving a long-lasting radiative cooling effect. Fourth, based on the aforementioned advantages, it eliminates the problems of inorganic nano-scattering particle wear and clogging of spinning equipment, making it promising for industrial production.

[0049] It should be noted that radiation-cooling fabric materials refer to woven materials with radiation-cooling properties. They have high reflectivity (low absorptivity) in the 0.4-2.5μm wavelength range and high infrared emissivity in the 8-13μm wavelength range, enabling them to achieve passive radiation cooling with zero energy consumption under direct sunlight.

[0050] It should be noted that twisting and weaving are understood in the general sense in this field. For example, twisting refers to feeding a fiber membrane loaded with inorganic nano-scattering particles into a twisting machine for twisting treatment. In this application embodiment, it is preferred to twist 180 times. Weaving can be knitting or weaving. Specifically, it is to weave the twisted fibers as warp and weft yarns. This application embodiment does not limit the specific weaving requirements, but the standard is that the formed product has good flexibility and good human comfort.

[0051] In specific embodiments, the polymer material is preferably one of polylactic acid, polyurethane, polyacrylonitrile, polyvinylidene fluoride, polyethylene, and polyacrylonitrile. The polymer materials in this application all contain molecular groups that can effectively absorb infrared wavelengths, enabling the formed nanofibers to have high infrared emissivity, which helps with radiative cooling. Furthermore, the polymer materials have good mechanical and physical properties, are readily available, and have low cost, thus meeting the performance requirements of everyday clothing.

[0052] In a specific embodiment, the mixed solvent contains a high-boiling-point solvent and a low-boiling-point solvent, with a mass ratio of 1:4. The high-boiling-point solvent is one of N,N-dimethylformamide and N,N-dimethylacetamide; the low-boiling-point solvent is one of acetone, chloroform, and dichloromethane. In this embodiment, dispersing the polymer in a mixed solvent of high-boiling-point and low-boiling-point solvents serves two purposes: firstly, it ensures efficient electrospinning and effectively prevents needle clogging; secondly, it allows control over the morphology and structure of the nanofibers, resulting in rod-shaped nanofibers that are easy to weave.

[0053] In a specific embodiment, the mass concentration of the precursor solution is preferably 10-16 wt%, specifically 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, or any value within the aforementioned concentration range. The precursor solution at this mass concentration possesses suitable polymer content and viscosity, thereby ensuring the smooth completion of the electrospinning operation and the formation of nanofibers with good structural morphology, which can endow the nanofibers with the potential ability to scatter sunlight.

[0054] In a specific embodiment, during electrospinning, the spinning voltage is preferably 18-24kV, specifically 18kV, 20kV, 22kV, 24kV, or any value within the aforementioned spinning voltage range; the feed speed is preferably 0.8-1.2mL / h, specifically 0.8mL / h, 1.0mL / h, 1.2mL / h, or any value within the aforementioned feed speed range; the receiving distance is preferably 14-18cm, specifically 14cm, 15cm, 16cm, 17cm, 18cm, or any value within the aforementioned receiving distance range. The test results of the embodiment show that using the above electrospinning parameters can form rod-shaped nanofibers with a wide diameter distribution.

[0055] In a specific embodiment, the nanofibers have a rod-shaped structure with a diameter of 300-800 nm. The diameter range of these rod-shaped nanofibers corresponds to wavelengths in the visible light band, thereby reducing the solar thermal gain effect based on Mie scattering and achieving a superior radiative cooling effect.

[0056] In specific embodiments, the inorganic nano-scattering particles are preferably one or more of TiO2, SiO2, ZnO, and Si3N2. The inorganic nano-scattering particles of this application have a high refractive index, which can generate high scattering efficiency in the nano-cooling fiber film, thereby improving the reflectivity of the radiation-cooling fabric material in the 0.4-2.5μm wavelength range and enhancing the radiation-cooling performance of the product material.

[0057] In a specific embodiment, the particle size of the inorganic nano-scattering particles is preferably 100-300 nm, and can specifically be 100 nm, 150 nm, 180 nm, 200 nm, 250 nm, 300 nm, or any value within the aforementioned particle size range. The inorganic nano-scattering particles with the specified diameter in this embodiment have a large specific surface area, giving them high refractive efficiency and surface energy. This helps to enhance the surface interaction between the inorganic nano-scattering particles and the nano-cooling fiber membrane, thereby achieving a better and more stable radiative cooling effect. Here, the particle size refers to the average diameter of the inorganic nano-scattering particles.

[0058] In a specific embodiment, the preferred mass concentration of inorganic nano-scattering particles in the nano-radiation particle dispersion is 1-4 wt%, specifically 1 wt%, 2 wt%, 3 wt%, 4 wt%, or any value within the aforementioned concentration range. This concentration in the embodiments of this application enables the nano-radiation particle dispersion to possess good flow dynamics, thereby ensuring good spraying effect and uniformity while maximizing the adhesion between the inorganic nano-scattering particles and the surface of the nano-cooling fiber, resulting in better radiative cooling performance of the product fabric material.

[0059] In a specific embodiment, during the spraying process, the flow rate and pressure are preferably 0.3-0.5 MPa, specifically 0.3 MPa, 0.4 MPa, 0.5 MPa, or any value within the aforementioned range; the receiving distance is preferably 5-10 cm, specifically 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, or any value within the aforementioned range. By setting the aforementioned flow rate, pressure, and receiving distance, this embodiment of the application can improve the uniformity and stability of the attached inorganic nano-scattering particles while effectively increasing the loading capacity of the inorganic nano-scattering particles, resulting in a long-lasting and excellent passive radiative cooling effect for the fabric material product.

[0060] In this application embodiment, the inorganic nano-scattering particle solid content and the temperature reduction amplitude T of the radiation-cooled fabric material are used as the reference. c The test values ​​were used, and the flow rate, pressure, and receiving distance of the spraying treatment were used as variable factors. The study was conducted based on the single-factor analysis method, and the results are shown in Table 1.

[0061] Table 1 - Solid content and cooling rate T of inorganic nano-scattering particles c Test results

[0062]

[0063]

[0064] As shown in Table 1, when the spraying flow rate and pressure are 0.5 MPa and the receiving distance is 8 cm, the inorganic nano-scattering particles have the highest solid content and the largest temperature drop (T) is observed. c Maximum, temperature drop T c The temperature reached 6.5℃, indicating that both flow rate, pressure, and receiving distance affect the solid content of inorganic nano-scattering particles and the radiation cooling effect of the radiation-cooling fabric material. In this embodiment, by setting the spraying flow rate and pressure to 0.3-0.5 MPa and the receiving distance to 5-10 cm, the radiation cooling effect of the radiation-cooling fabric material was effectively improved.

[0065] Secondly, embodiments of this application provide a radiation-cooling fabric material manufactured using the method described above. The manufacturing method effectively controls the morphology and diameter of the formed fibers and the solid content of the inorganic nano-scattering particles, enabling the nanofibers to possess radiation-cooling properties and achieve a significant synergistic effect with the inorganic nano-scattering particles. Therefore, the radiation-cooling fabric material manufactured using this method has low cost and high radiation-cooling effect.

[0066] The technical solution of this application will be further described below with reference to specific embodiments.

[0067] Example 1

[0068] This embodiment provides a method for manufacturing a radiation-cooling fabric material rcM1, specifically including:

[0069] S101: Disperse 10 parts by mass of polylactic acid in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform, and stir for 6 hours to obtain a precursor solution with a mass concentration of 10 wt%.

[0070] S102: A precursor solution with a mass concentration of 10wt% was placed into an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 20kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain rod-shaped nano-cooling fibers F1 with a diameter of 300-800nm.

[0071] S103: Disperse 1 part by mass of nano-TiO2 in 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water, add 5 parts by mass of tetrabutyl titanate, stir, and obtain a nano-radiation particle dispersion with a mass concentration of 1 wt%.

[0072] S104: A 1 wt% nano-radiation particle dispersion was placed in a spray gun and uniformly sprayed onto the surface of nano-refrigeration fiber F1 under the conditions of a flow rate and pressure of 0.5 MPa and a receiving distance of 8 cm. After twisting to coat the nano-refrigeration fiber F1 with inorganic nano-scattering particles, a thermosetting treatment was performed to obtain a cured refrigeration fiber bundle with a loading of 38.1 wt%.

[0073] S105: The cured fiber bundle with a loading of 38.1 wt% is woven in a conventional weaving method (machine weaving) to obtain the radiation cooling fabric material rcM1.

[0074] Example 2

[0075] This embodiment provides a method for manufacturing a radiation-cooling fabric material rcM2, specifically including:

[0076] S201: Disperse 10 parts by mass of polylactic acid in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform, and stir for 6 hours to obtain a precursor solution with a mass concentration of 10 wt%.

[0077] S202: A precursor solution with a mass concentration of 10wt% was placed into an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 20kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain rod-shaped nano-cooling fibers F1 with a diameter of 300-800nm.

[0078] S203: Disperse 3 parts by mass of nano-TiO2 in 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water, add 5 parts by mass of tetrabutyl titanate, stir, and obtain a nano-radiation particle dispersion with a mass concentration of 3wt%.

[0079] S204: A 3 wt% nano-radiation particle dispersion was placed in a spray gun and uniformly sprayed onto the surface of nano-refrigeration fiber F2 under the conditions of a flow rate and pressure of 0.5 MPa and a receiving distance of 8 cm. After twisting to coat the nano-refrigeration fiber F2 with inorganic nano-scattering particles, a thermosetting treatment was performed to obtain a cured fiber bundle with a loading of 41.8 wt%.

[0080] S205: The cured fiber bundle with a loading of 41.8 wt% is woven in a conventional weaving method (machine weaving) to obtain the radiation cooling fabric material rcM2.

[0081] Example 3

[0082] This embodiment provides a method for manufacturing a radiation-cooling fabric material rcM3, specifically including:

[0083] S301: Disperse 15 parts by mass of polylactic acid in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform, and stir for 6 hours to obtain a precursor solution with a mass concentration of 15 wt%.

[0084] S302: A precursor solution with a mass concentration of 15wt% was placed into an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 24kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain rod-shaped nano-cooling fibers F2 with a diameter of 300-800nm.

[0085] S303: Disperse 1 part by mass of nano ZnO in 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water, add 5 parts by mass of tetrabutyl titanate, stir, and obtain a nano-radiation particle dispersion with a mass concentration of 1 wt%.

[0086] S304: A 1 wt% nano-radiation particle dispersion was placed in a spray gun and uniformly sprayed onto the surface of nano-cooling fiber F2 under the conditions of a flow rate and pressure of 0.5 MPa and a receiving distance of 8 cm. After twisting to coat the nano-cooling fiber F2 with inorganic nano-scattering particles, a thermosetting treatment was performed to obtain a cured fiber bundle with a loading of 37.4 wt%.

[0087] S305: A bundle of cured fiber with a loading of 37.4 wt% is woven using conventional weaving methods (machine weaving) to obtain radiation cooling fabric material rcM3.

[0088] Example 4

[0089] This embodiment provides a method for manufacturing rcM4, a radiation-cooling fabric material, specifically including:

[0090] S401: Disperse 15 parts by mass of polyurethane in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform, and stir for 6 hours to obtain a precursor solution with a mass concentration of 15 wt%.

[0091] S402: A precursor solution with a mass concentration of 15wt% was placed into an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 22kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain rod-shaped nano-cooling fibers F3 with a diameter of 300-800nm.

[0092] S403: Disperse 1 part by mass of nano-TiO2 in 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water, add 5 parts by mass of tetrabutyl titanate, stir, and obtain a nano-radiation particle dispersion with a mass concentration of 1 wt%.

[0093] S404: A 1 wt% nano-radiation particle dispersion was placed in a spray gun and uniformly sprayed onto the surface of nano-refrigeration fiber F3 under the conditions of a flow rate and pressure of 0.5 MPa and a receiving distance of 8 cm. After twisting to coat the nano-refrigeration fiber F3 with inorganic nano-scattering particles, a thermosetting treatment was performed to obtain a cured refrigeration fiber bundle with a loading of 38.1 wt%.

[0094] S405: A bundle of cured fiber with a loading of 38.1 wt% is woven using conventional weaving methods (machine weaving) to obtain radiation cooling fabric material rcM4.

[0095] Example 5

[0096] This embodiment provides a method for manufacturing a radiation-cooling fabric material rcM5, specifically including:

[0097] S501: 15 parts by mass of polylactic acid are dispersed in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform. After stirring for 6 hours, 4 parts by mass of nano-TiO2 and tetrabutyl titanate are added and stirred for a period of time to obtain a precursor solution with a mass concentration of 15 wt%.

[0098] S502: A precursor solution with a mass concentration of 15wt% was placed into an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 20kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain nano-cooling fiber F4 with a loading of 25.1wt%.

[0099] S503: Nano-refrigeration fiber F4 with a loading of 25.1 wt% is subjected to thermosetting treatment to obtain a cured fiber bundle;

[0100] S504: The cured fiber bundles are woven using conventional weaving methods (machine weaving) to obtain the radiation cooling fabric material rcM5.

[0101] Example 6

[0102] This embodiment provides a method for manufacturing rcM6, a radiation-cooling fabric material, specifically including:

[0103] S601: Disperse 15 parts by mass of polylactic acid in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform, and stir for 6 hours to obtain a precursor solution with a mass concentration of 15 wt%.

[0104] S602: A precursor solution with a mass concentration of 15wt% was placed in an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 24kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain rod-shaped nano-cooling fibers F2 with a diameter of 300-800nm.

[0105] S603: Disperse 1 part by mass of nano-TiO2 in 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water, add 5 parts by mass of tetrabutyl titanate, stir, and obtain a nano-radiation particle dispersion with a mass concentration of 1 wt%.

[0106] S604: The nano-cooling fiber F2 was immersed in a nano-radiation particle dispersion with a mass concentration of 1 wt% and stirred for 3 hours. After being taken out, it was twisted to coat the inorganic nano-scattering particles with the nano-cooling fiber F2. The mixture was then heat-cured to obtain a cured fiber bundle with a loading of 9.1 wt%.

[0107] S605: The cured fiber bundles are woven using conventional weaving methods (machine weaving) to obtain the radiation cooling fabric material rcM6.

[0108] Example 7

[0109] This embodiment provides a method for manufacturing a radiation-cooling fabric material rcM7, specifically including:

[0110] S701: Disperse 15 parts by mass of polylactic acid in a mixed solvent consisting of 20 parts by mass of N,N-dimethylformamide and 80 parts by mass of chloroform, and stir for 6 hours to obtain a precursor solution with a mass concentration of 15 wt%.

[0111] S702: A precursor solution with a mass concentration of 15wt% was placed in an electrospinning machine, and electrospinning was carried out under the conditions of a spinning voltage of 20kV, a feed speed of 1.0mL / h, and a receiving distance of 15cm to obtain nano-cooling fiber F5.

[0112] S703: The nano-cooling fiber F5 is subjected to heat curing treatment to obtain a cured fiber bundle;

[0113] S704: The cured fiber bundles are woven using conventional weaving methods (machine weaving) to obtain the radiation cooling fabric material rcM7.

[0114] To verify the technical effects of the above embodiments, this application conducts structural characterization and performance testing on the radiation-cooling fabric materials prepared in Examples 1-6, specifically including:

[0115] 1. SEM characterization

[0116] The nano-cooling fiber F1 and the radiation-cooling fabric material rcM1 prepared in Example 1 were characterized by SEM, and the results were as follows: Figures 1 to 2 As shown. Among them, Figure 1 SEM image of nano-refrigeration fiber F1; Figure 2 SEM image of rcM1, a radiation-cooled fabric material.

[0117] according to Figure 1 It can be seen that the prepared nanofiber F1 has a smooth morphology without liquid droplets and a wide diameter distribution, which can enhance Mie scattering to a certain extent and scatter some visible light, thus possessing passive radiative cooling performance.

[0118] according to Figure 2 It can be seen that inorganic nano-scattering particles can form a good adhesion effect with nano-cooling fiber F1, and are not easy to fall off. This can play a long-term synergistic role and help to achieve long-term high-efficiency radiation cooling performance.

[0119] 2. Ultraviolet-Visible-NearInfrared Reflectance Test

[0120] The reflectance of the radiation-cooled fabric material rcM1 prepared in Example 1 was tested in the ultraviolet-visible-near-infrared bands, and the results were as follows: Figure 3 It can be seen that, among them, Figure 3 Reflectance curves of rcM1, a radiation-cooled fabric material, in the ultraviolet-visible-near-infrared bands.

[0121] according to Figure 3 It can be seen that the radiation cooling fabric material rcM1 has a high reflectivity to visible light in the ultraviolet-visible band, with an average reflectivity of up to 93%, which can minimize the heat absorption caused by visible light.

[0122] 3. Atmospheric window band emissivity test

[0123] The emissivity of the radiation-cooled fabric material rcM1 prepared in Example 1 was tested in the atmospheric window band, and the results were as follows: Figure 4 It can be seen that, among them, Figure 4 Emissivity curves of rcM1 for radiation-cooled fabric materials in the atmospheric window band.

[0124] according to Figure 4 It can be seen that the radiation cooling fabric material rcM1 can radiate heat to the cold outer space through atmospheric windows, and the average emissivity is 94%.

[0125] 4. Ultraviolet-Visible-NearInfrared Reflectance Testing of Radiation-Cooled Fabric Material rcM1 and Radiation-Cooled Fabric Material rcM7

[0126] The reflectance of radiation-cooled fabric materials rcM1 and rcM7 in the ultraviolet-visible-near-infrared bands was tested, and the results were as follows: Figure 5 It can be seen that, among them, Figure 5 The ultraviolet-visible-near-infrared reflectance curves of radiation-cooled fabric materials rcM1 and rcM7.

[0127] according to Figure 5 It can be seen that the radiation-cooled fabric material rcM1 has a higher reflectivity in the ultraviolet-visible-near-infrared band compared with the radiation-cooled fabric material rcM7 without nanoparticle loading, and the increase in reflectivity is very significant, indicating that inorganic nano-scattering particles and nano-cooling fibers have a synergistic effect.

[0128] 5. Cooling effect test

[0129] The cooling effect of the radiation-cooling fabric material rcM1 prepared in Example 1 was compared with that of different materials. The results were as follows: Figure 6 As shown. Among them, Figure 6 A comparison of the cooling effect of rcM1 radiation cooling fabric material with different materials.

[0130] according to Figure 6 It can be seen that, under the sunlight simulator, the radiation-cooled fabric material rcM1 has a better cooling effect than cotton and spandex.

[0131] 6. Outdoor cooling effect test

[0132] The outdoor cooling effect of the radiative cooling fabric material rcM1 prepared in Example 1 was tested, and the results were as follows: Figure 7 As shown. Among them, Figure 7 The image shows the cooling effect of rcM1 radiative cooling fabric material in an outdoor environment.

[0133] according to Figure 7 It can be seen that when the radiative cooling fabric material rcM1 is placed in an outdoor natural environment, its cooling effect is significantly better than that of non-woven fabric.

[0134] To further illustrate the performance of the radiation-cooling fabric material rcM1-7 prepared in Examples 1-7, the radiation-cooling performance of the radiation-cooling fabric material rcM1-7 was tested in this example, and the results are shown in Table 2.

[0135] Table 2 - Test results of radiation cooling performance of radiation-cooling fabric materials

[0136]

[0137] As shown in Table 2, the radiation-cooling fabric material prepared in the embodiments of this application has high visible light reflectivity (92-95%) and atmospheric window emissivity (93-94%), and the passive radiation cooling effect is very obvious.

[0138] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0139] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this application.

Claims

1. A method for manufacturing a radiation-cooling fabric material, characterized in that, The method includes: To dissolve the polymer material in a mixed solvent to form a precursor solution; The precursor solution was electrospun to obtain nano-cooling fibers; The nano-radiation particle dispersion was sprayed onto the surface of the nano-cooling fiber, and then twisted, thermoset, and woven sequentially to obtain a radiation-cooling fabric material. The nano-radiation particle dispersion contains inorganic nano-scattering particles and tetrabutyl titanate. The nanofibers have a rod-shaped structure with a diameter of 300-800 nm. During the spraying process, the flow rate and pressure are 0.5 MPa, and the receiving distance is 8 cm. The inorganic nano-scattering particles have a loading of 30-45% on the surface of the nano-refrigeration fiber; The solvent of the nano-radiation particle dispersion contains anhydrous ethanol and deionized water in a mass ratio of 9:

1.

2. The manufacturing method according to claim 1, characterized in that, The polymer material is one of polylactic acid, polyurethane, polyacrylonitrile, polyvinylidene fluoride, and polyethylene.

3. The manufacturing method according to claim 2, characterized in that, The mixed solvent contains a high-boiling-point solvent and a low-boiling-point solvent; The high-boiling-point solvent is one of N,N-dimethylformamide and N,N-dimethylacetamide; The low-boiling-point solvent is one of acetone, chloroform, and dichloromethane; The mass ratio of the high-boiling-point solvent to the low-boiling-point solvent is 1:

4.

4. The manufacturing method according to claim 3, characterized in that, The mass concentration of the polymer material in the precursor solution is 10-16 wt%.

5. The manufacturing method according to claim 4, characterized in that, During electrospinning, the spinning voltage is 18-24kV, the feed speed is 0.8-1.2mL / h, and the receiving distance is 14-18cm.

6. The manufacturing method according to claim 1, characterized in that, The inorganic nano-scattering particles are one or more of TiO2, SiO2, ZnO, and Si3N2; The inorganic nano-scattering particles have a particle size of 100-300 nm.

7. The manufacturing method according to claim 6, characterized in that, The mass concentration of inorganic nano-scattering particles in the nano-radiation particle dispersion is 1-4 wt%.

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