Zero-energy-consumption double-module thermal management fabric and preparation method thereof

Abstract

The invention relates to the technical field of thermal management, and discloses a zero-energy-consumption double-module thermal management fabric and a preparation method thereof.The method comprises the steps that polydimethylsiloxane, thermochromic powder and ultraviolet absorbent powder are mixed to be uniform, and a spinning solution is prepared; coaxial wet spinning is adopted, a spinning solution serves as a skin material, silicone oil serves as a core material, nascent fibers pass through coagulating bath silicone oil, and hollow fibers are obtained; pouring the PNIPAM pre-gel solution into the hollow fiber in an oxygen-free atmosphere, and standing and polymerizing at the temperature of-5 to 0 DEG C to obtain a functional fiber; and weaving the functional fibers into a fabric, namely the zero-energy-consumption double-module thermal management fabric. Through coaxial wet spinning, the phase-change hydrogel can be applied to the field of fabrics under the condition that the phase-change hydrogel does not make contact with the outside, water loss of the hydrogel is prevented, and circularity is enhanced. The fabric has the capability of resisting sudden change of external environment temperature, and more possibilities are provided for wide application of the zero-energy-consumption double-module heat management fabric in multiple fields.

Description

Technical Field

[0001] The invention relates to the technical field of thermal management, and in particular to a zero-energy consumption dual-module thermal management fabric and a preparation method thereof. Background Art

[0002] In the past decade, the demand for cooling and heating in human society has increased dramatically. About 37% of energy consumption throughout the year is used for cooling and heating of buildings.

[0003] Therefore, exploring advanced thermal management technologies is crucial for sustainable development. Among them, radiative thermal management stands out as a technology that can regulate the heat exchange process through infrared (IR) radiation without additional energy consumption. The sub-ambient cooling capacity of radiative cooling materials comes from the fact that they can emit heat through the transparent window of the atmosphere to the cold outer space with a temperature of only ~3K, while reflecting a large amount of solar radiation heat (i.e., having a high solar emissivity). In recent years, various high-performance radiative cooling materials based on thermal emitters have been developed one after another, mainly used in building energy saving and personal thermal management. According to the spectral response characteristics of such materials in the mid-infrared band, radiative cooling materials can be mainly divided into two categories: non-selective thermal emitters and selective thermal emitters. Non-selective thermal emitters refer to radiative cooling materials that have high emissivity in the entire mid-infrared band. The present invention is a non-selective emitter. However, traditional radiative thermal management materials (RTMM) usually only have a single passive temperature management capability, and zero-energy RTMM materials also have only a single sunlight selection capability, which limits their application range. Therefore, it is urgent to develop zero-energy temperature dual-management radiative thermal management materials with a wider range of applications.

[0004] In recent years, there are two main directions for the research on thermal management of zero-energy dual-modules that take into account both radiative cooling and solar light modulation: using the thermochromic properties of certain materials to achieve effective modulation of sunlight, and combining radiative cooling materials or structural design to achieve better thermal management of zero-energy dual-modules. Another direction is to use the photochromic properties of certain materials to achieve effective modulation of sunlight, and combine radiative cooling materials or structural design to achieve better thermal management of zero-energy dual-modules. However, due to its complexity, the research on thermal management of zero-energy dual-modules has not been widely studied and applied, and it is still the focus of current research. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes a simple high-temperature wet spinning and multi-material combination strategy to manufacture zero-energy dual-module thermal management fabrics. Through biaxial high-temperature wet spinning, hollow thermochromic fibers are spun, solving the problem that flexible fibers are difficult to combine with thermochromic powders, and phase change hydrogel is poured into the fiber core to achieve refrigeration and heat preservation dual management capabilities comparable to ordinary cotton fabrics, while having the ability to resist sudden changes in external environmental temperature.

[0006] To achieve the above object, on the one hand, the present invention provides a method for preparing a zero-energy dual-module thermal management fabric, which comprises the following steps:

[0007] S1, mixing polydimethylsiloxane (PDMS), thermochromic powder and ultraviolet absorber powder evenly, and adding a curing agent matching PDMS to prepare a spinning solution;

[0008] The color change temperature of the thermochromic powder is 31°C, it is white above this temperature and black below this temperature, its particle size is 3-9μm, the maximum tolerance temperature is not less than 210°C, and it is insoluble in water; the model of the ultraviolet absorber powder is UV-329, which has low toxicity, small powder particles, easy subsequent spinning, and high ultraviolet absorbance; the mass ratio of polydimethylsiloxane, thermochromic powder and ultraviolet absorber powder is 100:(10-20):(0.5-1.5), and this ratio is that the configured spinning solution can achieve continuous spinnability of the fiber, and while spinning high-quality fibers, it can also make the fabric have good sunlight modulation ability and a long outdoor service life;

[0009] S2, using a coaxial wet spinning method, using the spinning solution prepared in step S1 as the skin material, and the vacuumed silicone oil as the core material, extruding through a coaxial needle to form a primary fiber with a skin-core structure, and then passing through a silicone oil coagulation bath at 190-210° C. to obtain a hollow fiber;

[0010] S3, washing the hollow fiber obtained in step S2 to remove the silicone oil on the inner and outer surfaces, and then pouring a poly N-isopropylacrylamide (PNIPAM) pregel solution mixed with N,N,N,N-tetramethylethylenediamine (TEMED) into the hollow fiber in an oxygen-free atmosphere, sealing both ends of the fiber after it is filled, and standing at a low temperature of -5-0°C until the PNIPAM pregel solution is polymerized into a hydrogel to obtain a dual-module functional fiber;

[0011] The phase transition temperature of the hydrogel polymerized from the PNIPAM pregel solution is consistent with the color change temperature of the thermochromic powder, which is also 31°C. Above this temperature, the hydrogel cross-linked network separates from water and absorbs heat. Below this temperature, the hydrogel cross-linked network combines with water and releases heat.

[0012] S4, weaving the functionalized fibers obtained in step S3 into a fabric, which is a zero-energy dual-module thermal management fabric.

[0013] As a further preferred technical solution of the present invention, a thermochromic powder model Chameleon TP-Black 31 is selected, which has a color change temperature of 31°C. It is white above this temperature and black below this temperature. Its particle size is 3-9μm, can be well dispersed in PDMS, and is high temperature resistant, reaching 220°C, so as not to affect high temperature wet spinning.

[0014] Furthermore, in order to spin high-quality fibers while also enabling the fabric to have good sunlight modulation capabilities and a long outdoor service life, in step S1, the mass ratio of polydimethylsiloxane, thermochromic powder, and ultraviolet absorber powder is 100:20:1. After selecting the optimal ratio of thermochromic powder and ultraviolet absorber, there is almost no effect on the molding of the spun hollow fiber. Under the premise of ensuring continuous spinnability of the fiber, the obtained fiber tube wall is uniform, smooth, and free of sand holes, and is convenient for the subsequent perfusion of the PNIPAM pregel solution.

[0015] In the technical solution of the present invention, the difficulty of cleaning the silicone oil in the core of the subsequent hollow fiber is comprehensively considered, as well as the ability of the fiber tube wall to withstand the high pressure generated when the protective atmosphere gas (such as Ar) passes through the fiber, the difficulty of injecting the pre-gel solution, and the outer diameter of the fiber is as small as possible to achieve the density of the subsequent fabric and the wall is as thin as possible to achieve a larger hydrogel filling amount, so that the effect of preventing temperature sudden change is more obvious. To this end, through a large number of experiments, it is found that in step S2, the size of the concentric axis needle is preferably 19G+12G.

[0016] As a further preferred technical solution of the present invention, in step S2, the spinning solution is poured into syringe No. 1, and the vacuumed silicone oil is poured into syringe No. 2. During the spinning process, by optimizing the solution propeller parameters of high-temperature wet spinning, the liquid volume of syringe No. 1 is 300 μL / m, and the liquid volume of syringe No. 2 is 280 μL / m, while ensuring that the fiber can be spun continuously, the wall thickness of the spun hollow fiber is uniform. In theory, if a larger capacity syringe is selected to carry more spinning solution, large-scale spinning can be carried out.

[0017] As a further preferred technical solution of the present invention, by optimizing the temperature of the coagulation bath, according to the coagulation degree and quality of spinning, in step S2, the silicone oil temperature of the coagulation bath is selected to be 200°C, and 500cs is the optimal viscosity of the silicone oil in the coagulation bath.

[0018] As a further preferred technical solution of the present invention, in step S3, the optimal content of NIPAM monomer in PNIPAM hydrogel is explored, and the filling amount of the fabric core at high temperature and the difficulty of bending the fabric at high temperature are comprehensively considered. It is concluded that when the PNIPAM drug ratio is fixed at 6g water, 20mg ammonium persulfate (APS), and 20mg N,N-methylenebisacrylamide (BIS), 0.6g N-isopropylacrylamide (NIPAM) monomer is the optimal monomer content; further, the amount of N,N,N,N-tetramethylethylenediamine (TEMED) added to the PNIPAM pregel solution is 13μL.

[0019] As a further preferred technical solution of the present invention, the oxygen-free atmosphere in step S3 uses an inert gas, and before the hollow fiber is perfused with the PNIPAM pregel solution, the hollow fiber needs to be filled with the inert gas to exclude oxygen. More preferably, the inert gas is argon.

[0020] According to another aspect of the present invention, the present invention also provides a zero-energy dual-module thermal management fabric, which is prepared by the above method. The thermal management fabric can be used as human clothing, tents or firefighting clothing for thermal management in summer and winter or at fire scenes.

[0021] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0022] 1) The preparation method proposed by the present invention is simple, and the fabric is easy to prepare on a large scale and industrially produce;

[0023] 2) The combination of the PDMS of the present invention and the thermochromic powder under high-temperature wet spinning enables the fabric to have zero-energy high-temperature and low-temperature dual-module thermal management capabilities. Specifically, under high temperatures in summer, the fabric has a high ability to reflect sunlight (0.3-2.5μm), and in the mid- and far-infrared bands, due to the spectral characteristics of PDMS, the fabric has a high emission capability in the entire band of 2.5-16μm, and through radiation cooling, the temperature is further reduced, making its cooling ability comparable to that of white cotton fabrics on the market. Under low temperatures in winter, the fabric has a high ability to absorb sunlight (0.3-2.5μm), and because the outdoor temperature is not high, the radiation cooling effect is not obvious, making its thermal insulation ability comparable to that of black cotton fabrics on the market.

[0024] 3) The present invention uses coaxial wet spinning to enable phase change hydrogel to be used in the fabric field without contact with the outside world, preventing water loss in the hydrogel and enhancing the recyclability. It also enables the fabric to resist sudden changes in external environmental temperature, providing more possibilities for the wide application of zero-energy dual-module thermal management fabrics in multiple fields.

[0025] 4) The present invention solves the problem that organic thermochromic powder is sensitive to ultraviolet rays and easily fades and becomes ineffective under ultraviolet radiation by mixing a certain proportion of UV-329 ultraviolet absorber into the spinning solution, thereby greatly extending the service life of the fabric outdoors. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0027] Figure 1 Schematic diagram of the experimental device for conducting outdoor experiments on the thermal management fabric sample of Example 1, Figure 1 a and Figure 1 b are schematic diagrams of the experimental device in Tianjin in summer and winter, respectively. The dotted line in the figure indicates the position where the upper opening of the foam box is sealed with LDPE film. The heating plate is kept at 37°C to simulate the human body temperature. The copper foil makes the lateral temperature diffuse evenly. Medical silicone is used to simulate the skin.

[0028] Figure 2 Experimental data and experimental conditions under sealing conditions in an outdoor experiment on September 17, 2024, including: (a) Real-time temperature curves of the zero-energy dual-module thermal management fabric (red line) and the PDMS hydrogel fabric (without UV-329) (orange line), black cotton fabric (blue line) and white cotton fabric (green line) used as a control experiment when sealed with polyethylene PE film; (b) Corresponding environmental conditions, including solar radiation, humidity and wind speed;

[0029] Figure 3 The experimental data and experimental conditions under sealing conditions in the outdoor experiment on December 3, 2024, including: (a) the real-time temperature curves of the zero-energy dual-module thermal management fabric (red line) and the black cotton fabric (blue line) and white cotton fabric (green line) used as control experiments when the polyethylene PE film is used for sealing; (b) the corresponding environmental conditions, including solar radiation, humidity and wind speed;

[0030] Figure 4 This is the spectrum of the thermal management fabric sample of Example 1.

[0031] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0032] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0033] Unless otherwise defined, the technical terms used in the following examples have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods, unless otherwise specified, are all conventional methods.

[0034] Example 1

[0035] 1) Dow Corning SYLGARD 184 silicone rubber polydimethylsiloxane (PDMS), Chameleon TP-Black 31 (thermochromic powder, produced by Shenzhen Huancai Bianse Technology) and UV-329 (ultraviolet absorber powder) were mixed in a mass ratio of 100:20:1, and high-power probe ultrasonic was used for 20 minutes. Dow Corning SYLGARD 184 silicone rubber curing agent was added in a mass ratio of 1:5 to PDMS, and the mixture was evenly mixed and shaken at high power for 20 minutes. Then, the mixed solution was repeatedly vacuumed three times, and the vacuuming time for each time was not less than 5 minutes to obtain a spinning solution.

[0036] 2) The spinning solution is poured into a 12 ml syringe 1, and the silicone oil is poured into a 12 ml syringe 2; the liquid volume of the syringe 1 propeller is adjusted to 300 μL / m, and the liquid volume of the syringe 2 propeller is adjusted to 280 μL / m, and high-temperature coaxial wet spinning is performed, wherein the spinning solution is used as the skin material and the silicone oil is used as the core material; the spinning needle (concentric axis needle) adopts an integrated, flush inside and outside, and side needle seat design, and the parameters are 19+12G. The two syringes are connected to the spinning needle through a commercial high-temperature resistant silicone tube (inner diameter 2mm, outer diameter 3mm) to form a double-tube injection. The coagulation bath for the primary fiber below the needle is 200°C, 500cs viscosity silicone oil. The fiber after the coagulation bath is collected by the automatic rotating shaft at the end. The spun hollow fiber is 12-16m long, with an outer diameter of about 1.3mm and an inner diameter of about 1mm.

[0037] 3) The obtained hollow fiber is immersed in isopropanol, sealed, and stored in a 60°C oven for 8 hours to allow the fiber to solidify and stabilize. The silicone oil on the core and outer surface of the hollow fiber is then repeatedly cleaned until it is completely cleaned, and then dried for later use.

[0038] 4) Preparation of PNIPAM pregel solution: 6 g H2O and 0.6 g NIPAM monomer were stirred at 60°C for half an hour until the monomer was completely dissolved, 20 mg APS and 20 mg BIS were added, dissolved evenly, and vacuum was applied to remove bubbles to obtain a PNIPAM pregel solution.

[0039] 5) The dried hollow fiber was placed in an Ar environment and Ar was passed through the core for 20 minutes; 13 μL of TEMED was dropped into the PNIPAM pre-hydrogel and mixed evenly, and Ar was injected into the solution at the same time to make sure that there was no oxygen in the solution. The mixed solution was then injected into the core of the hollow fiber with a syringe. After it was filled, the two ends of the fiber were sealed and stored at 0°C for 1 day under Ar conditions to successfully cross-link the hydrogel in the fiber core to obtain functionalized fibers.

[0040] 6) The obtained functionalized fibers are woven into fabrics for subsequent testing.

[0041] The fabric samples of Example 1 were tested for the following properties:

[0042] like Figure 1 As shown in the figure, an outdoor test was conducted to verify the cooling and heating performance of the thermal management fabric of the zero-energy dual-module. In the experiment, a sample of size 4cm×4cm was used, and the thermal management ability of the sample was tested under two conditions: high temperature in summer and low temperature in winter. The role of the LDPE film used in the experimental device is to reduce the interference of heat radiation and air convection of surrounding buildings on the test results of the sample. During the test, the sample was placed in a foam box (porous foam material) with aluminum foil on the inner wall to isolate the heat convection and the heat radiation of the surrounding complex environment to the greatest extent. In order to simulate the actual test conditions of the fabric when it is made into clothing, we placed a thin heating sheet at the bottom, and by adjusting the low-voltage source parameters, it was kept at a near human body temperature of 37℃ at room temperature. The top of the heating sheet was tightly attached to the copper foil, and the top of the copper foil was attached to the simulated skin with a small slot. The small slot was inserted with a thermocouple and filled with thermal conductive silicone grease to ensure its good thermal conductivity and present the real skin surface temperature under the fabric cover. Copper foil is an excellent conductor, and its temperature diffuses quickly and evenly, which can reflect the temperature of the entire sample, making the temperature of the thermocouple test more accurate. At the same time, the comprehensive meteorological station simultaneously records meteorological data including humidity, solar radiation intensity and wind speed ( Figure 2 b and Figure 3 b).

[0043] like Figure 2 As shown in Figure a, under high solar radiation intensity and without heat convection, the cooling capacity of the zero-energy dual-module thermal management fabric is comparable to that of commercial white cotton fabric and ~5K lower than that of commercial black cotton fabric. In addition, at the beginning of the test, due to the presence of phase change hydrogel, the temperature changes slowly, and the fabric has the ability to resist sudden temperature changes on the outside, and the greater the temperature difference between the inside and outside, the more obvious the function. Figure 2As shown in Figure a, when the outdoor test was carried out for about 165 minutes, the PDMS hydrogel fabric without UV-329 began to fail, the cooling capacity decreased, and the temperature increased compared with the thermal management fabric of the zero-energy dual-module group. It can be seen that UV-329 has a significant effect on extending the outdoor service life of the fabric.

[0044] like Figure 3 As shown in the figure, under low solar radiation intensity and without heat convection, the heating capacity of the zero-energy dual-module thermal management fabric of this embodiment is comparable to that of commercial black cotton fabric and is 4.1K higher than that of commercial white cotton fabric. In addition, in experiments under summer and winter conditions, Figure 4 As shown, in the high temperature of summer, the fabric has a high ability to reflect sunlight (0.3-2.5μm), and in the mid- and far-infrared bands, due to the spectral characteristics of PDMS, the fabric has a high ability to emit light in the entire band of 2.5-16μm. Through radiation cooling, the temperature is further reduced, making its cooling ability comparable to that of white cotton fabrics on the market. In the low temperature of winter, the fabric has a high ability to absorb sunlight (0.3-2.5μm), especially in the visible light band (0.4-0.76μm), and because the outdoor temperature is not high, the radiation cooling effect is not obvious, making its thermal insulation ability comparable to that of black cotton fabrics on the market.

[0045] The above test results effectively prove that the thermal management fabric of the zero-energy dual-module provides a zero-energy thermal management strategy. Therefore, the thermal management fabric of the zero-energy dual-module of the present invention can automatically switch the cooling / insulation mode according to the environment, and has huge energy-saving potential. It can be used as a normal wearable fabric or tent, automatically adapting to the ambient temperature to make the internal temperature comfortable, or used as firefighting clothing at the fire scene. The fabric automatically switches the cooling and heating modes according to the changes in the external temperature, and the cooling capacity is equivalent to that of commercial white cotton fabrics, and the heating capacity is equivalent to that of commercial black cotton fabrics. While zero energy consumption, it can also prevent the adverse effects of sudden changes in external temperature on the human body. The multifunctional thermal management fabric of the zero-energy dual-module has a wide range of application prospects.

[0046] In order to further demonstrate the beneficial technical effects of the present invention, the following experiments were also conducted.

[0047] 1. Based on the scheme of Example 1, a control experiment was performed by only changing the "PDMS: Chameleon TP-Black 31 mass ratio and not using UV-329". Table 1 shows the effect of the PDMS: Chameleon TP-Black 31 mass ratio on the visible light reflectance modulation at high and low temperatures. The data results were measured by a UV-visible near-infrared spectrophotometer.

[0048] Based on the above control experiments, it was concluded that when the mass ratio of PDMS: Chameleon TP-Black 31 was 5:1, the visible light modulation ability was the best; and when the ratio was greater than 5:1, the viscosity of the spinning solution was too high and continuous spinning could not be performed.

[0049] Table 1 Effect of PDMS: Chameleon TP-Black 31 mass ratio on visible light reflectance modulation at high and low temperatures

[0050] PDMS:Chameleon TP-Black 31 mass ratio Visible light reflectance modulation at high and low temperatures 5:1 47.6％ 10:1 44.8％ 20:1 42.4％

[0051] 2. Based on the scheme of Example 1, a control experiment was conducted by only changing the "type of UV absorber / reflector". Table 2 shows the effects of different UV absorbers / reflectors on the feasibility of wet spinning and the anti-failure ability of Chameleon TP-Black 31, i.e., the UV absorption / reflection ability test.

[0052] Based on the above control experiments, it is concluded that the UV-329 used in the spinning solution system of the invention is an ultraviolet absorber suitable for continuous spinning and has strong ultraviolet absorption ability.

[0053] Table 2 Selection of UV absorbers / reflectors

[0054] UV absorbers / reflectors Can it continue spinning? Xenon lamp irradiation fabric (1500W / ㎡2h) Blank control √ fade Benzophenone ×(dissolves into PDMS above 48.5℃, precipitates at low temperature) / Tartrazine √ fade UV-1 ×(Evaporation in the solidification region at 200℃) / UV-234 √ fade UV-329 √ No fade

[0055] In Table 2, “√” indicates yes and “×” indicates no.

[0056] 3. Based on the scheme of Example 1, a control experiment was conducted by changing only the "content of UV-329". Table 3 shows the effect of the content of UV-329 on spinning and fabrics.

[0057] Based on the above control experiments, it was concluded that the PDMS:UV-329 mass ratio of 100:1 is the optimal spinning ratio, which can meet the ultraviolet absorption capacity of the fabric and will not affect continuous spinning.

[0058] Table 3 Effect of UV-329 content on spinning and fabrics

[0059]

[0060] 4. Based on the scheme of Example 1, a control experiment was conducted by changing only the "solidification temperature". Table 4 shows the effect of the solidification temperature on the spinning process.

[0061] Based on the above control experiments, the temperature should be as low as possible while ensuring good fiber forming in order to save operating time costs, and 200°C is found to be the optimal coagulation temperature for the spinning process.

[0062] Table 4 Effect of coagulation temperature on spinning

[0063] Solidification temperature (silicone oil) 160℃ 180℃ 200℃ Spinning influence Dispersed in the solidification domain, difficult to solidify Slow solidification leads to uneven fiber morphology Good fiber coagulation and formation

[0064] 5. Based on the scheme of Example 1, a control experiment was conducted by only changing the "wet spinning needle model". Table 5 shows the effects of different models of wet spinning needles on the size of the spun fibers.

[0065] Based on the above control experiments, the selection of fibers should consider the difficulty of cleaning the silicone oil in the core, the ability of the fiber tube wall to withstand the high pressure generated when Ar passes through the fiber, the difficulty of injecting the pre-gel solution, and the fiber outer diameter should be as small as possible to achieve the density of the subsequent fabric and the wall should be as thin as possible to achieve a larger hydrogel filling amount, so that the effect of preventing sudden temperature changes is more obvious. Comprehensive selection, 19G+12G wet spinning needle, can meet the best process requirements.

[0066] Table 5 Effect of different wet spinning needle models on the spun fiber size

[0067] Needle Model 19G+14G 19G+12G 19G+10G 16G+12G 14G+10G 12G+8G Inner diameter of spun fiber (mm) ～0.8 ～1.0 ～1.1 ～1.2 ～1.4 ～1.5 Outer diameter of spun fiber (mm) ～1.0 ～1.3 ～1.5 ～1.5 ～1.6 ～1.8

[0068] 6. Based on the scheme of Example 1, a control experiment was conducted by changing only the "NIPAM monomer content of PNIPAM". Table 6 shows the effects of different NIPAM contents on PNIPAM.

[0069] Based on the above control experiment, since the cross-linked network formed by PNIPAM polymerization at high temperature will separate from the water molecules, too high NIPAM content will make the cross-linked network too hard, and the woven fabric is difficult to bend. In addition, at high temperatures, the volume of PNIPAM will shrink, and this shrinkage should be minimized to ensure that the core of the fabric has sufficient filling. After comprehensive comparison, based on the gel material system of Example 1, it is concluded that the PNIPAM formed by the polymerization of 0.6g NIPAM monomer has better met the process requirements.

[0070] Table 6 Effect of NIPAM monomer content on PNIPAM after polymerization

[0071]

[0072] In Table 6, “√” indicates that the requirements are met, and “×” indicates that the requirements are not met.

[0073] Although specific embodiments of the present invention are described above, those skilled in the art should understand that these are merely examples and that various changes or modifications may be made to the embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is limited only by the appended claims.

Claims

1. A method for preparing a zero-energy dual-module thermal management fabric, characterized in that: The following steps are involved: S1, mixing polydimethylsiloxane, thermochromic powder and ultraviolet absorber powder evenly, adding a curing agent matching PDMS, preparing a spinning solution and vacuuming; The color change temperature of the thermochromic powder is 31°C, it is white above this temperature and black below this temperature, its particle size is 3-9 μm, the maximum tolerance temperature is not less than 210°C, and it is insoluble in water; the type of the ultraviolet absorber powder is UV-329; the mass ratio of polydimethylsiloxane, thermochromic powder and ultraviolet absorber powder is 100:(10-20):(0.5-1.5); S2, using a coaxial wet spinning method, using the spinning solution prepared in step S1 as the skin material, and the vacuumed silicone oil as the core material, extruding through a coaxial needle to form a primary fiber with a skin-core structure, and then passing through a silicone oil coagulation bath at 190-210° C. to obtain a hollow fiber; S3, washing the hollow fiber obtained in step S2 to remove the silicone oil on the inner and outer surfaces, and then pouring a poly (N-isopropylacrylamide) pregel solution mixed with N,N,N,N-tetramethylethylenediamine into the hollow fiber in an oxygen-free atmosphere, sealing both ends of the fiber after it is filled, and standing at -5-0°C until the poly (N-isopropylacrylamide) pregel solution is polymerized into a hydrogel to obtain a dual-module functional fiber; S4, weaving the functionalized fibers obtained in step S3 into a fabric, which is a zero-energy dual-module thermal management fabric.

2. The method for preparing the zero-energy dual-module thermal management fabric according to claim 1, characterized in that: In step S1, the mass ratio of polydimethylsiloxane, thermochromic powder and ultraviolet absorber powder is 100:20:

1.

3. The method for preparing the zero-energy dual-module thermal management fabric according to claim 1, characterized in that: In step S2, the type of the concentric axis needle is 19G+12G.

4. The method for preparing the zero-energy dual-module thermal management fabric according to claim 1, characterized in that: In step S2, the spinning solution is poured into syringe No. 1, and the vacuumed silicone oil is poured into syringe No.

2. During the spinning process, the liquid volume in syringe No. 1 is 300 μL / m, and the liquid volume in syringe No. 2 is 280 μL / m.

5. The method for preparing the zero-energy dual-module thermal management fabric according to claim 1, characterized in that: In step S2, the temperature of the silicone oil in the coagulation bath is 200°C and the viscosity is 500 cs.

6. The method for preparing the zero-energy dual-module thermal management fabric according to claim 1, characterized in that: In step S3, the poly (N-isopropylacrylamide) pregel solution is prepared by mixing the following components: 6 g of water, 20 mg of ammonium persulfate, 20 mg of N,N-methylenebisacrylamide, and 0.6 g of N-isopropylacrylamide monomer.

7. The method for preparing the zero-energy dual-module thermal management fabric according to claim 6, characterized in that: In step S3, the amount of N,N,N,N-tetramethylethylenediamine added to the poly (N-isopropylacrylamide) pregel solution is 13 μL.

8. The method for preparing the zero-energy dual-module thermal management fabric according to claim 1, characterized in that: The oxygen-free atmosphere in step S3 uses an inert gas, and before the hollow fiber is perfused with the poly (N-isopropylacrylamide) pregel solution, the inert gas needs to be filled into the hollow fiber.

9. A zero-energy dual-module thermal management fabric, characterized in that: The method is prepared by any one of claims 1 to 8.

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