Humidity response type high-reflection strong-convection composite nanofiber cooling fabric and preparation method thereof

Abstract

The invention discloses a humidity response type high-reflection strong-convection composite nanofiber cooling fabric and a preparation method thereof, and relates to the technical field of fiber manufacturing. The humidity response type high-reflection severe-convection composite nanofiber cooling fabric comprises an electrostatic fabric substrate and a reflection nanoparticle coating, wherein the surface of the electrostatic fabric substrate is coated with the reflection nanoparticle coating; a penetrating notch is formed in the electrostatic textile fabric base. Through the high-reflection material and the strong convection design, the cooling fabric capable of effectively reflecting solar radiation and enhancing convection flow of heat energy is obtained, so that the temperature of a human body in a hot environment is reduced, the sensible temperature of the human body can be maintained in an optimal physiological interval, the comfort of the human body is improved, and body health is guaranteed. The high-reflection and strong-convection fabric provided by the invention can provide efficient heat management performance, and the use of the fabric can reduce the dependence on traditional cooling equipment such as an air conditioner, so that the energy consumption and carbon emission are reduced.

Description

Technical Field

[0001] This invention relates to the field of fiber manufacturing technology, and in particular to a humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric and its preparation method. Background Technology

[0002] In recent years, extreme high temperatures have become more frequent in summer, significantly impacting human production and daily life. Textiles, acting as the human body's second skin, play a crucial role in resisting changes in external environmental temperature. Thermally conditioned clothing, which manages body temperature by regulating fabric properties, has gradually become a hot research area. Fabrics, as a barrier between the human body and the environment, can control heat exchange between them through adjustments to their physical structure and material properties.

[0003] In high-temperature environments, fabrics not only need excellent protective functions but also need to release additional heat by enhancing the interaction between the human body and the environment, thereby ensuring the comfort and safety of personnel in high-temperature environments. Outdoors, due to the direct influence of solar radiation, solar energy becomes the primary source of energy for the human body. Cooling fabrics generally achieve this by creating a surface with high solar reflectivity. The core of high solar reflectivity clothing cooling lies in enhancing the material's surface reflectivity to sunlight, reflecting most of the sunlight into the environment, thus reducing the absorption of solar energy by the human body. Simultaneously, based on the body's own thermoregulation mechanism, when the body temperature rises, sweat is secreted, and heat is carried away through sweat evaporation to achieve cooling. When the body temperature exceeds 34℃, sweat evaporation becomes the body's primary cooling mechanism. Traditional textiles act as barriers to sweat evaporation; in hot weather, the inability of sweat to evaporate in time increases the burden on the body and causes various skin problems. Developing humidity-responsive fabrics, where the fabric absorbs moisture and opens "channels" when the body sweats, reduces the barrier between the human body and the environment, thereby accelerating the rapid excretion of sweat. Regulating the heat transfer process through this high convection method is a suitable strategy for cooling in high-temperature environments. Two types of fabrics that accelerate sweat evaporation are bicomponent yarns capable of diameter changes in high humidity environments and fabric-based flap actuators. Notably, the opening and closing of the flaps results in a larger effective working area and higher heat transfer efficiency.

[0004] However, the overall performance of related fabrics on the market still needs further improvement, especially in the synergistic optimization of high reflectivity and strong convection cooling functions, where there is still a lack of systematic research and mature products.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric and its preparation method, so as to solve the problems existing in the prior art.

[0007] To achieve the above objectives, the present invention provides the following solution:

[0008] One of the technical solutions of this invention is to provide a humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric, comprising:

[0009] An electrostatic textile substrate and a reflective nanoparticle coating applied to the surface of the electrostatic textile substrate;

[0010] The electrostatic textile substrate has a through-cut.

[0011] As a further preferred embodiment of the present invention, the reflective nanoparticles in the reflective nanoparticle coating include at least one of BaSO4, ZnO and TiO2.

[0012] As a further preferred embodiment of the present invention, the through cut is a quadrilateral cut with three sides open and one side closed; the size of the through cut is (0.5-2.0)cm×(0.5-2.0)cm.

[0013] As a further preferred embodiment of the present invention, the size of the through cut is 0.5cm × 0.5cm.

[0014] As a further preferred embodiment of the present invention, the arrangement of the through cuts is a matrix arrangement.

[0015] As a further preferred embodiment of the present invention, the material of the electrostatic textile substrate is nylon.

[0016] The second technical solution of this invention is to provide a method for preparing the above-mentioned humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric, comprising the following steps:

[0017] S1: Nanofiber fabrics are prepared by electrospinning technology;

[0018] S2: The reflective nanoparticles are formulated into a color paste, coated onto the surface of the electrostatic textile substrate, and dried to obtain an electrospun coated fabric.

[0019] S3: The electrospun coated fabric is cut to obtain a through cut, thereby obtaining the humidity-responsive high-reflectivity strong convection composite nanofiber cooling fabric.

[0020] As a further preferred embodiment of the present invention, the method for preparing the electrostatic textile substrate includes the following steps: mixing formic acid, acetic acid and nylon powder, using the resulting mixture as a spinning solution, and preparing the electrostatic textile substrate by electrospinning.

[0021] As a further preferred embodiment of the present invention, the electrospinning voltage is 22kV, the injection speed is 0.5mL / h, and the collecting roller speed is 200 rpm.

[0022] As a further preferred embodiment of the present invention, the mass concentration of BaSO4 in the BaSO4 color paste is 10%-30%; the mass concentration of ZnO in the ZnO color paste is 54%-57%; and the mass concentration of TiO2 in the TiO2 color paste is 43%-48%.

[0023] The third technical solution of the present invention is to provide the application of the above-mentioned humidity-responsive, high-reflectivity, strong-convective composite nanofiber cooling fabric in the preparation of outdoor work clothes, sportswear, or high-temperature environment protection equipment.

[0024] The present invention discloses the following technical effects:

[0025] This invention utilizes highly reflective materials and a strong convection design to create a cooling fabric that effectively reflects solar radiation and enhances heat convection, thereby lowering the body temperature in hot environments and maintaining the perceived body temperature within the optimal physiological range (31-34℃), thus improving comfort and protecting health. Firstly, based on the Mie scattering theory, this invention uses nanoparticles with wavelengths similar to sunlight to create a coating on the surface of a nanofiber fabric, achieving high reflectivity. Simultaneously, it leverages the moisture-absorbing and expanding properties of nylon nanofiber fabric by designing flaps on the fabric. When the body sweats, the fabric absorbs moisture and bends, opening channels for sweat evaporation and creating a microenvironment for convective heat exchange, enhancing heat exchange between the environment and the body through evaporative cooling. This invention cleverly combines high reflectivity and strong convection cooling methods into the same fabric, achieving highly efficient cooling. Both high reflectivity and strong convection cooling strategies are passive cooling technologies, enabling zero-energy, zero-pollution spontaneous cooling. The use of this type of highly reflective, high-convection fabric can reduce reliance on traditional cooling equipment such as air conditioners in hot environments, thereby reducing energy consumption and carbon emissions. Outdoor workers and athletes can reduce their risk of heatstroke and improve work efficiency by wearing this fabric. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1The full-spectral reflectance of the electrospun fabric and the three nanoparticle-coated fabrics with different contents is shown in Figure 1. (a) is the electrospun fabric (marked as uncoated (electrospun)), (b) is the BaSO4-coated fabric, (c) is the ZnO-coated fabric, and (d) is the TiO2-coated fabric.

[0028] Figure 2 Heating / cooling performance curves of coated fabrics prepared with three nanoparticles at different concentrations; where (a) is ZnO coated fabric, (b) is BaSO4 coated fabric, and (c) is TiO2 coated fabric.

[0029] Figure 3 BaSO4 coated fabric with an opening of 2*0.5cm 2 Real-time photographs of moisture applied under the fabric (0–16 s) and after moisture removal (24–65 s).

[0030] Figure 4 The opening is 2*0.5cm. 2 The bending angle of the BaSO4-coated fabric during the application and removal of moisture.

[0031] Figure 5 BaSO4 coated fabric with an opening of 1*0.5cm 2 Real-time photographs of moisture applied under the fabric (0–16 s) and moisture removed (30–70 s).

[0032] Figure 6 The opening is 1*0.5cm. 2 The bending angle of the BaSO4-coated fabric during the application and removal of moisture.

[0033] Figure 7 BaSO4 coated fabric with an opening of 0.5*0.5cm 2 Real-time photographs of moisture applied under the fabric (0–16 s) and moisture removed (25–70 s).

[0034] Figure 8 The opening is 0.5*0.5cm. 2 The bending angle of the BaSO4-coated fabric during the application and removal of moisture.

[0035] Figure 9 The experiment was conducted on the heating / cooling of a humidity-responsive, high-reflectivity, strong-convective composite nanofiber cooling fabric. (a) shows the temperature before opening, (b) shows the temperature after opening, (c) shows the temperature at the start of sunlight exposure, and (d) shows the temperature at the end of sunlight exposure.

[0036] Figure 10 The heating / cooling curves of the humidity-responsive, high-reflectivity, strong-convective composite nanofiber cooling fabric are shown in the heating / cooling experiment. Detailed Implementation

[0037] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0038] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0039] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. 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.

[0040] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0041] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0042] One objective of this invention is to provide a humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric, comprising:

[0043] An electrostatic textile substrate and a reflective nanoparticle coating applied to the surface of the electrostatic textile substrate;

[0044] The electrostatic textile substrate has a through-cut.

[0045] Preferably, the reflective nanoparticles in the reflective nanoparticle coating include at least one of BaSO4, ZnO, and TiO2.

[0046] Preferably, the through cut is a quadrilateral cut with three open sides and one closed side; the size of the through cut is (0.5-2.0)cm × (0.5-2.0)cm.

[0047] Preferably, the size of the through cut is 0.5cm × 0.5cm.

[0048] Preferably, the arrangement of the through cuts is a matrix arrangement.

[0049] Preferably, the substrate of the electrostatic textile is made of nylon.

[0050] The second objective of this invention is to provide a method for preparing the above-mentioned humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric, comprising the following steps:

[0051] S1: Nanofiber fabrics are prepared by electrospinning technology;

[0052] S2: The reflective nanoparticles are formulated into a color paste, coated onto the surface of the electrostatic textile substrate, and dried to obtain an electrospun coated fabric.

[0053] S3: The electrospun coated fabric is cut to obtain a through cut, thereby obtaining the humidity-responsive high-reflectivity strong convection composite nanofiber cooling fabric.

[0054] Preferably, the method for preparing the electrostatic textile substrate includes the following steps: mixing formic acid, acetic acid and nylon powder, using the resulting mixture as a spinning solution, and preparing the electrostatic textile substrate by electrospinning.

[0055] Preferably, the electrospinning voltage is 22kV, the injection speed is 0.5mL / h, and the collecting roller speed is 200 rpm.

[0056] Preferably, the mass concentration of BaSO4 in the BaSO4 color paste is 10%-30%; the mass concentration of ZnO in the ZnO color paste is 54%-57%; and the mass concentration of TiO2 in the TiO2 color paste is 43%-48%.

[0057] The third objective of this invention is to provide the application of the above-mentioned humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric in the preparation of outdoor work clothes, sportswear, or high-temperature environment protection equipment.

[0058] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0059] Example 1

[0060] Preparation of humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric:

[0061] (1) Preparation of electrostatic textile substrate

[0062] Formic acid and acetic acid were blended in a 1:1 mass ratio, and 15% (w / w) of nylon 6 (PA6) powder was added to the mixture. The resulting mixture was stirred overnight to completely dissolve the PA6 powder. Subsequently, the spinning solution was loaded into a syringe and placed in an injection pump. At room temperature, under an applied voltage of 22 kV and an injection rate of 0.5 mL / h, a cylindrical roller was rotated at 200 rpm to collect the polymer fibers. Finally, the PA6 fabric was peeled off from the aluminum foil substrate to obtain freestanding PA6 fabric (electrotextile). The resulting electrotextile had a thickness of 160 micrometers.

[0063] (2) Preparation of electrospun coated fabrics

[0064] BaSO4, ZnO, and TiO2 color pastes were prepared separately, and the color paste formulations are shown in Tables 1, 2, and 3. Different concentrations of BaSO4, ZnO, and TiO2 nanoparticle color pastes were rapidly and uniformly applied to electrospun fabrics (the coating thickness of the coating machine was set to 350 μm), and then placed in a 60℃ constant temperature oven for 5 minutes to obtain electrospun coated fabrics.

[0065] Table 1 BaSO4 Pigment Formulation

[0066]

[0067] Table 2 ZnO Pigment Formulation

[0068]

[0069] Table 3. TiO2 Pigment Formulation

[0070]

[0071] (3) Preparation of humidity-responsive, high-reflectivity, strong-convective composite nanofiber cooling fabric

[0072] A rectangular pattern with three open sides and one closed side is cut from the coated fabric obtained in step (2) to obtain a humidity-responsive, high-reflectivity, strong-convective composite nanofiber cooling fabric.

[0073] Because the nanofibers and nanopores inside electrostatic textiles have excellent light-reflective properties, they exhibit high reflectivity. Applying a nanoparticle coating to the fabric surface further enhances this reflectivity.

[0074] Figure 1The full-spectrum (380-2500 nm) reflectance of electrospun fabrics and coated fabrics with different nanoparticle contents is given; where (a) is the electrospun fabric (marked as uncoated (electrospun)), (b) is the BaSO4 coated fabric, (c) is the ZnO coated fabric, and (d) is the TiO2 coated fabric. Figure 1 As shown, the average reflectance of electrospun coated fabrics with different concentrations of three nanoparticles was improved.

[0075] The coated fabric was placed under a solar simulator with a solar intensity set to 1000 W / m². 2 The fabric was exposed to sunlight for 380 seconds, then the sunlight simulator was turned off. A thermocouple was attached to the underside of the fabric to record the temperature changes during the heating / cooling process in real time. Figure 2 The heating / cooling curves show that the heat-shielding performance of the electrospun coated fabric is further improved compared with that of the pure electrospun fabric, and the heat-shielding performance of the barium sulfate and zinc oxide coatings is stronger than that of the titanium dioxide coating.

[0076] A rectangular pattern with three open sides and one closed side is cut out on the fabric with a scalpel. The electrostatic textile itself has good water absorption properties and expands after absorbing moisture. However, the coating on the surface of the fabric does not have significant moisture absorption properties. Therefore, after absorbing moisture, the fabric will bend towards the coating side, thereby obtaining a coated fabric with high reflection and strong convection, achieving a high reflection and strong convection effect.

[0077] Figure 3 BaSO4 coated fabric with an opening of 2*0.5cm 2 Real-time photographs of the fabric under which moisture is applied (0–16 s) and after moisture removal (24–65 s). From Figure 3 It can be seen that 2.0*0.5cm 2 Before moisture is applied (0s), the fabric at the cut is in a closed state. After moisture is applied, the fabric quickly bends upward, reaching its maximum bending angle at 16s. After the moisture is removed, the fabric begins to gradually close, reaching a bent and closed state at 65s. The changes in the bending and closing angles of the fabric during moisture application and removal are as follows: Figure 4 As shown. The method of applying moisture is as follows: nitrogen gas from a nitrogen cylinder is passed through water and then applied to the underside of the fabric, with the nitrogen flow rate controlled at 5 psi.

[0078] Figure 4 The opening is 2*0.5cm. 2 The bending angle of the BaSO4-coated fabric during the application and removal of moisture.

[0079] Figure 5 BaSO4 coated fabric with an opening of 1*0.5cm 2Real-time photographs of the fabric under which moisture is applied (0–16 s) and after moisture removal (30–70 s). From Figure 5 It can be seen that 1.0*0.5cm 2 Before moisture is applied (0s), the fabric at the cut is in a closed state. After moisture is applied, the fabric quickly bends upward, reaching its maximum bending angle at 16s. After the moisture is removed, the fabric begins to gradually close, reaching a bent and closed state at 70s. The changes in the bending and closing angles of the fabric during moisture application and removal are as follows: Figure 6 As shown.

[0080] Figure 6 The opening is 1*0.5cm. 2 The bending angle of the BaSO4-coated fabric during the application and removal of moisture.

[0081] Figure 7 BaSO4 coated fabric with an opening of 0.5*0.5cm 2 Real-time photographs of the fabric under which moisture is applied (0–16 s) and after moisture removal (25–70 s). From Figure 7 It can be seen that 0.5*0.5cm 2 Before moisture is applied (0s), the fabric at the cut is in a closed state. After moisture is applied, the fabric quickly bends upward, reaching its maximum bending angle at 16s. After the moisture is removed, the fabric begins to gradually close, reaching a bent and closed state at 70s. The changes in the bending and closing angles of the fabric during moisture application and removal are as follows: Figure 8 As shown.

[0082] Figure 8 The opening is 0.5*0.5cm. 2 The bending angle of the BaSO4-coated fabric during the application and removal of moisture.

[0083] By comparing the bending angle curves of the high-reflectivity convection fabric during the application and removal of moisture from these three sizes of slits, the 2*0.5cm slit size was determined to be the most suitable. 2 The maximum bending angle of the coated fabric is approximately 35°, and the opening size is 1.0*0.5cm. 2 The maximum bending angle of the coated fabric is approximately 32°, and the opening size is 0.5*0.5cm. 2 The maximum bending angle of the coated fabric is approximately 45°. The bending and closing times of the three fabric sizes are basically the same, therefore the appropriate cut size is 0.5*0.5cm. 2 The coated fabric exhibits the best bending properties.

[0084] like Figure 9A 0.5cm x 0.5cm square opening was cut into the center of an electrostatic textile coated with barium sulfate using a scalpel, forming a neat 4x4 matrix of small openings. An 8.5cm diameter petri dish was used as a base, and a paper towel soaked in water was placed inside to simulate the evaporation of sweat from the human body during sunlight exposure. The sample was then placed under a sunlight simulator with a sunlight intensity set to 1000W / m². 2 Before exposure to sunlight, the fabric's cut edges were closed. After 380 seconds of sunlight exposure, it was clearly visible that the cut edges had bent due to the evaporation of moisture. Thermocouples were attached to the underside of the fabric to record the temperature changes during the fabric's heating / cooling process in real time. Figure 10 The thermocouple-recorded heating / cooling curves of the fabric during this process show that the fabric temperature gradually increased after sunlight exposure, then remained at a maximum of around 31°C. This temperature is about 6°C lower than that of the pure BaSO4 electrospun coated fabric with no openings. This experiment demonstrates that the humidity-responsive strong convection design can further enhance the fabric's cooling performance. The fabric combining high reflectivity and strong convection reduced its temperature by approximately 9°C compared to the pure electrospun fabric under the same sunlight intensity and exposure time, showcasing its highly efficient cooling capability.

[0085] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric, characterized in that, include: An electrostatic textile substrate and a reflective nanoparticle coating applied to the surface of the electrostatic textile substrate; The electrostatic textile substrate has a through-cut.

2. The humidity-responsive, high-reflectivity, high-convective composite nanofiber cooling fabric according to claim 1, characterized in that, The reflective nanoparticles in the reflective nanoparticle coating include at least one of BaSO4, ZnO, and TiO2.

3. The humidity-responsive, high-reflectivity, high-convective composite nanofiber cooling fabric according to claim 1, characterized in that, The through incision is a quadrilateral incision with three open sides and one closed side; the size of the through incision is (0.5-2.0)cm × (0.5-2.0)cm.

4. The humidity-responsive, high-reflectivity, high-convective composite nanofiber cooling fabric according to claim 3, characterized in that, The dimensions of the through cut are 0.5cm × 0.5cm.

5. The humidity-responsive, high-reflectivity, high-convective composite nanofiber cooling fabric according to claim 1, characterized in that, The arrangement of the through-cuts is a matrix arrangement.

6. The humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric according to claim 1, characterized in that, The substrate of the electrostatic textile is made of nylon.

7. The method for preparing the humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric according to any one of claims 1-6, characterized in that, Includes the following steps: S1: Nanofiber fabrics are prepared by electrospinning technology; S2: The reflective nanoparticles are formulated into a color paste, coated onto the surface of the electrostatic textile substrate, and dried to obtain an electrospun coated fabric. S3: The electrospun coated fabric is cut to obtain a through cut, thereby obtaining the humidity-responsive high-reflectivity strong convection composite nanofiber cooling fabric.

8. The preparation method according to claim 7, characterized in that, The method for preparing the electrostatic textile substrate includes the following steps: mixing formic acid, acetic acid and nylon powder, using the resulting mixture as a spinning solution, and preparing the electrostatic textile substrate by electrospinning.

9. The application of the humidity-responsive, high-reflectivity, high-convection composite nanofiber cooling fabric as described in any one of claims 1-6 in the preparation of outdoor work clothes, sportswear, or high-temperature environment protection equipment.

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