Flexible fabric with photothermal conversion and infrared shielding performance and preparation method

Abstract

The invention discloses a flexible fabric with photothermal conversion and infrared shielding properties and a preparation method thereof. The preparation method comprises the following steps: (1) mixing dopamine hydrochloride and alkyl siloxane, adding water and stirring to obtain a homogeneous-phase transparent solution; (2) immersing a flexible fabric into the transparent solution for reaction to obtain a modified fabric; (3) mixing an AgNO3 solution with PVP, stirring the mixture under a dark condition until the mixture is dissolved, and then adding a NaHCO3 solution until a milk white solution is generated; soaking the modified fabric in the milky white solution, and continuously stirring under a dark condition to obtain a mixture; and (4) taking a sulfur source solution, adding the sulfur source solution into the mixture, stirring and reacting under a dark condition, and drying after the reaction is finished to obtain the flexible fabric with photothermal conversion and infrared shielding properties. The flexible fabric has photothermal conversion and infrared shielding properties at the same time, application of the flexible fabric in the field of infrared stealth of wearable equipment and outdoor goods is promoted, and high-value development of traditional fabric is facilitated.

Description

Technical Field

[0001] This invention relates to a functional flexible fabric and its preparation method, particularly a flexible fabric with photothermal conversion and infrared shielding properties and its preparation method. Background Technology

[0002] Photothermal conversion materials are a class of materials that utilize the photothermal effect to generate radiant heat. These materials not only affect energy conversion efficiency but also expand the range of applications. Photothermal conversion materials cover a variety of types, including: metal carbides, such as MXenes; transition metal oxides, such as ferric oxide, lanthanum chromate, and cobalt tetroxide; noble metal nanoparticles, such as gold, platinum, and silver; non-metallic carbon-based materials, such as graphene, carbon fiber, and carbon black; and organic photothermal materials, such as polypyrrole, polydopamine, and polyaniline. See Science China Materials 2018, 61(7), 905-914.

[0003] It is worth noting that metal sulfides such as copper sulfide, silver sulfide (Ag₂S), and molybdenum disulfide have attracted much attention due to their strong broad-spectrum light absorption, low re-emission rate, low cost, and excellent light absorption performance, making them very suitable for photothermal catalysis and energy generation. (See Journal of Materials Chemistry A, 2022, 10(48), 25509-25526). Among nanostructured chalcogenides, group I-VI silver sulfide (Ag₂S) stands out due to its low toxicity, narrow band gap, good chemical stability, high absorption coefficient, and excellent optical properties. It is widely used in semiconductors, photovoltaic cells, infrared detectors, and superionic conductors, and in recent years it has also been applied to room-temperature photoelectric switches and oxygen sensors. For example, Song et al. discussed silver / silver sulfide (Ag / Ag2S) bifacial nanoparticles with hydrogen peroxide-activated near-infrared II (NIR-II) fluorescence (achieved by reducing electron transfer) and photoacoustic imaging capabilities in Nano Letters, 2021, 21(6), 2625-2633, which enable highly sensitive non-invasive in vivo diagnosis of liver injury and cancer.

[0004] Infrared (IR) adaptability is a ubiquitous phenomenon in nature and biological systems. Inspired by organisms in nature, researchers are dedicated to developing advanced infrared adaptive materials with applications spanning multiple infrared-related technological fields, including smart camouflage, thermal management, and biomedicine. In recent years, research has focused on developing such biomimetic adaptive materials, particularly for infrared camouflage and radiative cooling applications. Developing infrared stealth technology requires materials to possess two capabilities simultaneously: reducing infrared transmission through infrared shielding and limiting heat transfer through thermal radiation shielding. These materials have enormous market potential in future technology industries, with applications in automotive, aerospace, energy equipment, and construction.

[0005] Currently, the most studied infrared stealth materials are mainly divided into two categories: metal semiconductor oxides and tungsten-based semiconductors. In addition, the infrared shielding performance of photothermal materials is comparable to that of tungsten-based semiconductors, showing good prospects in the fields of infrared shielding and thermal insulation films. It is worth noting that Wu's team synthesized reduced graphene oxide / copper sulfide (rGO / CuS) composite aerogel by controlling the loading of copper sulfide (CuS) and thermal reduction process in Nano-Micro Letters, 2022, 14(1), 171. The introduction of copper sulfide effectively modulates the infrared emissivity and thermal insulation performance of the material, providing a new strategy for designing flexible, lightweight, adaptive, processable and scalable metal sulfide-based infrared stealth materials.

[0006] Fabrics worn daily are receiving increasing attention in the field of functional materials research due to their inherent flexibility, breathability, and biocompatibility, making them ideal materials for wearable devices and outdoor products. However, the inherent hydrophilicity of fabrics leads to a decrease in their moisture absorption and heat retention properties, and accelerates icing in cold environments, limiting their practical applications. Meanwhile, existing functional textiles often focus on a single performance characteristic, and achieving multifunctional integration remains a key challenge.

[0007] The purpose of this invention is to provide a flexible fabric with photothermal conversion and infrared shielding properties, and a method for preparing the same. The flexible fabric of this invention possesses both photothermal conversion and infrared shielding properties, promoting its application in the field of infrared stealth in wearable devices and outdoor products, and facilitating the high-value development of traditional fabrics.

[0008] A method for preparing a flexible fabric with photothermal conversion and infrared shielding properties is provided, comprising the following steps: (1) Mix dopamine hydrochloride with alkylsiloxane, then add water and stir until homogeneous and transparent solution is obtained; (2) Immerse the flexible fabric in the transparent solution, and then rinse it with water until unreacted dopamine hydrochloride and alkylsiloxane are removed to obtain the modified fabric. (3) Take AgNO3 solution, add PVP to it, stir until dissolved under light-protected conditions, then add NaHCO3 solution until a milky white solution is formed; then soak the modified fabric in the milky white solution and continue stirring under light-protected conditions to obtain a mixture; (4) Take the sulfur source solution and add it to the mixture in step (3). Stir the mixture under light-protected conditions. After the reaction is complete, wash with water to remove unreacted monomers and then dry to obtain a flexible fabric with photothermal conversion and infrared shielding properties.

[0009] Preferably, the aforementioned method for preparing the flexible fabric with photothermal conversion and infrared shielding properties is specifically as follows: (1) Mix 0.5-3 parts by weight of dopamine hydrochloride with 0.8-5.5 parts by weight of alkylsiloxane, then add water and stir until homogeneous to obtain a transparent solution; (2) Immerse the flexible fabric in the transparent solution for soaking reaction, and after the reaction, wash with water until unreacted dopamine hydrochloride and alkylsiloxane are removed to obtain the modified fabric; (3) Take 0.4-0.5 parts by mass of AgNO3 and add water to prepare an AgNO3 solution with a concentration of 10-50 mmol / L. Add PVP to the AgNO3 solution at a molar ratio of PVP:AgNO3 of 1-2:1 and stir under light-protected conditions until dissolved to obtain a mixed solution. Then, prepare 0.1-0.2 parts by mass of NaHCO3 to prepare a NaHCO3 solution with a concentration of 30-80 mmol / L and add it to the mixed solution to obtain a milky white solution. Finally, immerse the modified fabric in the milky white solution and continue stirring under light-protected conditions to obtain a mixture. (4) Take 0.113 parts by mass of sulfur source to prepare a sulfur source solution with a concentration of 30-80 mmol / L, and then add it to the mixture in step (3). Stir and react under light-protected conditions. After the reaction is completed, wash with water to remove unreacted monomers, and then dry to obtain a flexible fabric with photothermal conversion and infrared shielding properties.

[0010] Preferably, in the aforementioned method for preparing a flexible fabric with photothermal conversion and infrared shielding properties, the flexible fabric is one of wool fabric, cotton fabric, or polyester fabric.

[0011] Preferably, in the aforementioned method for preparing flexible fabrics with photothermal conversion and infrared shielding properties, the wool fabric includes pure wool fabrics and blended fabrics of wool with cotton, polyester, spandex, nylon, acrylic, silk, or linen; the cotton fabric includes pure cotton fabrics or blended fabrics of cotton with polyester, spandex, acrylic, viscose fiber, silk, or linen; and the polyester fabric includes pure polyester fabrics and blended fabrics of polyester with wool, cotton, spandex, acrylic, viscose fiber, silk, or linen.

[0012] Preferably, in the aforementioned method for preparing flexible fabrics with photothermal conversion and infrared shielding properties, the alkylsiloxane is one of dodecyltrimethoxysilane, tetradecyltrichlorosilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, or octadecyltrimethoxysilane.

[0013] Preferably, in the aforementioned method for preparing flexible fabrics with photothermal conversion and infrared shielding properties, the sulfur source solution is one of thioacetamide solution, sodium sulfide solution, or thiourea solution.

[0014] Preferably, in the aforementioned method for preparing flexible fabric with photothermal conversion and infrared shielding properties, the soaking reaction in step (2) is carried out at a temperature of 25-60°C for 1-3 days, with the fabric being turned over every 10-15 hours.

[0015] Preferably, in the aforementioned method for preparing flexible fabric with photothermal conversion and infrared shielding properties, after the modified fabric in step (3) is immersed in the milky white solution, it is stirred for 6-24 hours under light-protected conditions.

[0016] Preferably, in the aforementioned method for preparing flexible fabric with photothermal conversion and infrared shielding properties, the stirring reaction in step (4) is carried out at a temperature of 25-50°C for 1-3 days; the drying temperature is 30-50°C for 24-48 hours.

[0017] A flexible fabric with photothermal conversion and infrared shielding properties is provided, prepared by the aforementioned method.

[0018] 1. This invention uses a polydopamine-assisted hydrophobic modification method, combined with in-situ growth of silver sulfide particles by precipitation conversion, to achieve integrated hydrophobic, stain-resistant, photothermal and infrared stealth functions on fabrics.

[0019] 2. The silver sulfide particle-modified fabric of the present invention exhibits excellent comprehensive performance. Its preparation process includes two key steps: First, dopamine combines with hydrolyzed alkylsiloxane through a hydroxyl-mediated reaction to fix the alkylsiloxane and obtain hydrophobic modified fabric; Second, the in-situ formed polydopamine layer further enhances the adhesion of silver sulfide particles to the fabric surface, and finally constructs a micro-nano hierarchical structure.

[0020] 3. The Ag2S particle-modified fabric of this invention possesses highly efficient hydrophobic and photothermal conversion capabilities, thus exhibiting excellent anti-icing / de-icing performance, making it suitable for cold outdoor environments. Furthermore, this material exhibits low reflectivity and low transmittance across a wide wavelength range of 2.5-20μm, thus possessing excellent infrared stealth performance, enabling personnel, plants, and vehicles to achieve concealment outdoors or in low-light conditions.

[0021] 4. This invention, based on a mild and convenient preparation method, achieves multifunctional and high-value modification of fabrics, overcoming the shortcomings of traditional fabrics such as poor water resistance, poor heat insulation, and inability to resist or remove ice. Furthermore, it endows fabrics with infrared light shielding properties. The successful implementation of this invention will provide important theoretical reference and technical support for the functional modification and high-value utilization of traditional fabrics, and the research results have significant scientific value and social benefits. Attached Figure Description

[0022] Figure 1 This is a flowchart illustrating the reaction principle and process flow of the present invention. Figure 2 Infrared images of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S); Figure 3 XRD patterns of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S); Figure 4 XPS plots of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S); Figure 5 SEM images of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S); Figure 6 Contact angle (ac), water jet ejection (df), UV absorption and protein adsorption (gi) of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S). Figure 7 UV-Vis-NIR absorption curves (a) of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S), temperature change curves under near-infrared light irradiation (b), temperature rise and fall curves under near-infrared light irradiation and non-irradiation (c), optical images of the samples and near-infrared images under near-infrared light irradiation (d). Figure 8 The image shows the anti-icing and de-icing effects of hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S). Figure 9 Infrared reflectance (a) and transmittance curves (b) of wool (WF), hydrophobically modified wool (HMWF), and hydrophobically modified wool fabric loaded with Ag2S (HMWF@Ag2S), and shielding effect diagram (c) on human body, plant and metal vehicle models. Detailed Implementation

[0023] The present invention will be further described below with reference to embodiments, but these embodiments are not intended to limit the scope of the invention.

[0024] Embodiments of the present invention (1) Anti-protein adsorption test: This study used a BSA static adsorption experiment to simulate the adsorption of proteins in blood on the surface of fabric samples to study the anti-protein adsorption performance of the fabric samples. Samples of each tissue were cut into 1cm × 3cm pieces and immersed in 10mL of a 1g / L BSA solution (pH=7.4). The samples were then placed at 25℃ for 12 hours at room temperature. After complete adsorption, the BSA solutions before and after immersion were collected, and the change in absorbance at 280nm was measured using a UV spectrophotometer. The commonly used calculation formula is: in It refers to the absorbance at a wavelength of 280nm. This is the molar absorptivity at 280 nm. The optical path length *l* refers to the length of the path (1 cm) that light travels through the sample. Higher absorbance indicates higher protein concentration. Note that since wool fabrics are rich in protein, the absorbance of the sample must be subtracted from the absorbance of the wool fabric itself at 280 nm.

[0025] The amount of protein adsorbed on the sample surface is then calculated using the following formula: in, The amount of BSA protein adsorbed on the membrane sample, in μg / cm³. 2 ; The concentration of BSA solution in the blank group is in mg / mL; The concentration of the sample group's solution is in mg / mL; The volume of the blank solution is in mL; S is the solution volume of the sample group, in mL; S is the effective area of ​​the membrane sample, in cm². 2 .

[0026] (2) Photothermal conversion efficiency test: The photothermal conversion efficiency (η) of the sample can be calculated. The formula is as follows: h represents the heat transfer coefficient, S represents the surface area, and ΔTmax is the maximum temperature change. I represents the power density, and A808 is the absorbance of the sample at a wavelength of 808 nm.

[0027] According to the technical solution of the present invention, 1.0g of dopamine hydrochloride and 1.8g of different alkylsiloxanes, such as tetradecyltrichlorosilane, hexadecyltrimethoxysilane or octadecyltrimethoxysilane, are added to a 250ml beaker. 100ml of water is added to the beaker, and the beaker is sonicated for 30min to form a homogeneous transparent solution.

[0028] Pour the solution into a glass petri dish containing pure wool fabric (10cm*10cm) so that the wool is completely immersed in the liquid; place the petri dish in a 50℃ oven and react for 48 hours, turning it over every 12 hours and then taking it out; wash the surface of the wool with running water for 3 minutes, and then place it in a 50℃ oven to dry for 24 hours to obtain hydrophobic modified wool.

[0029] Prepare a 25 mmol / L solution (100 ml) of AgNO3 with 425 mg (2.5 mmol). Add PVP-K27 to the AgNO3 solution according to the PVP / AgNO3 molar ratio of 3:2. Stir magnetically under dark conditions until dissolved. Add 30 ml of 50 mmol / L NaHCO3 solution (0.126 g) dropwise to form a milky white solution. Soak hydrophobically modified wool (10 cm * 10 cm) in the above-prepared solution and continue to stir magnetically under dark conditions for 6 h.

[0030] Prepare a 50 mmol / L thioacetamide solution, add 30 ml of the solution dropwise, and react with magnetic stirring for 1 day under light-protected conditions. Then wash the wool surface with running water for 3 min and dry it in a 50℃ oven for 24 h to obtain the hydrophobic modified wool fabric loaded with Ag2S.

[0031] The products obtained from different alkylsiloxanes in Example 1 were tested, and the relevant results are shown in Table 1 below: Table 1: Alkylsiloxanes from Different Sources serial number Alkylsiloxane Hydrophobic modified wool contact angle <![CDATA[Contact Angle / Photothermal Conversion Efficiency of Hydrophobically Modified Wool Fabric Loaded with Ag2S]]> <![CDATA[Anti-icing / De-icing Performance of Hydrophobically Modified Fabric Loaded with Ag2S (Melting Time of 0.5 ml Ice Balls at NIR 808 nm, 1.31 W / cm 2 when melting time)]]> 1 Tetradecyltrichlorosilane 125.6° 128.7° / 60.8% 33s 2 hexadecyltrimethoxysilane 132.2° 139.3° / 62.3% 30s 3 Octadecyltrimethoxysilane 134.5° 141.4° / 63.4% 28s This example fully demonstrates that hydrophobic modified wool fabrics and Ag2S-loaded hydrophobic modified wool fabrics can be prepared from different types of alkylsiloxanes, which fully demonstrates the universality of this patent regarding the types of alkylsiloxanes.

[0032] According to the technical solution of the present invention, 1.0g of dopamine hydrochloride and 1.8g of hexadecyltrimethoxysilane are added to a 250ml beaker, 100ml of water is added to the beaker, and the beaker is sonicated for 30min to form a homogeneous transparent solution.

[0033] The solution was poured into a glass petri dish containing fabric (10cm*10cm) so that different types of fabric, such as pure cotton, wool or polyester fabric, were completely immersed in the liquid. The petri dish was placed in a 50℃ oven for 48 hours and turned over every 12 hours before being removed. The surface of the fabric was washed with running water for 3 minutes and then placed in a 50℃ oven to dry for 24 hours to obtain different types of hydrophobic modified fabrics.

[0034] A 25 mmol / L solution was prepared using 425 mg of AgNO3. PVP-K27 was added to the AgNO3 solution at a PVP / AgNO3 molar ratio of 3:2, and the mixture was magnetically stirred in the dark until dissolved. 30 ml of 50 mmol / L NaHCO3 solution (0.126 g) was added dropwise to produce a milky white solution. Different types of hydrophobic modified fabrics (10 cm * 10 cm) were immersed in the above-prepared solution and magnetically stirred for 6 hours in the dark.

[0035] Prepare a 50 mmol / L thioacetamide solution, add 30 ml of the solution dropwise, and stir magnetically for 1 minute under light-protected conditions. Then wash the surface with running water for 3 minutes and dry it in a 50°C oven for 24 hours to obtain a hydrophobic modified fabric loaded with Ag2S.

[0036] The products of different types of fabrics in Example 2 were tested, and the relevant results are shown in Table 2 below: Table 2: Studies on different types of fabrics serial number fabric Contact angle of hydrophobic modified fabric <![CDATA[Contact Angle / Photothermal Conversion Efficiency of Hydrophobically Modified Fabric Loaded with Ag2S]]> <![CDATA[Anti-icing / De-icing Performance of Hydrophobically Modified Fabric Loaded with Ag2S (Melting Time of 0.5 ml Ice Balls at NIR 808 nm, 1.31 W / cm 2 when)]]> 1 pure cotton cloth 131.6° 135.8° / 61.7% 32s 2 pure wool 132.2° 139.3° / 62.3% 30s 3 Polyester 124.5° 131.6° / 58.3% 35s This example fully demonstrates that hydrophobically modified fabrics loaded with Ag2S can be prepared using different types of fabrics, exhibiting good photothermal conversion efficiency and anti-icing / de-icing properties. This clearly demonstrates the universality of this patent regarding the types of fabrics used.

[0037] According to the technical solution of the present invention, 1.0g of dopamine hydrochloride and 1.8g of hexadecyltrimethoxysilane are added to a 250ml beaker, 100ml of water is added to the beaker, and the beaker is sonicated for 30min to form a homogeneous transparent solution.

[0038] Pour the solution into a glass petri dish containing a 10cm*10cm fabric, completely immersing the wool fabric in the liquid; place the petri dish in a 50℃ oven for 48 hours, turning it over every 12 hours and then removing it; wash the wool surface with running water for 3 minutes, and then place it in a 50℃ oven to dry for 24 hours to obtain the hydrophobic modified wool fabric.

[0039] A 25 mmol / L solution was prepared using 425 mg of AgNO3. PVP-K27 was added to the AgNO3 solution at a PVP / AgNO3 molar ratio of 3:2, and the mixture was magnetically stirred in the dark until dissolved. 30 ml of a 50 mmol / L NaHCO3 solution was added dropwise, resulting in a milky white solution. A 10 cm x 10 cm hydrophobic modified wool fabric was then immersed in the prepared solution, and magnetic stirring was continued for 6 hours in the dark.

[0040] Prepare 50 mmol / L solutions of different sulfur sources, add 30 ml of each solution to the above solutions, and stir magnetically for 1 minute under light-protected conditions. Then wash the wool surface with running water for 3 minutes. After washing the surface, dry it in a 50°C oven for 24 hours to obtain the hydrophobic modified fabric loaded with Ag2S.

[0041] The products from fabrics with different sulfur sources in Example 3 were tested, and the relevant results are shown in Table 3 below: Table 3: Studies on different types of sulfur sources serial number sulfur source <![CDATA[Photothermal conversion efficiency of hydrophobic modified fabric loaded with Ag2S]]> <![CDATA[Anti-icing / De-icing Performance of Hydrophobically Modified Fabric Loaded with Ag2S (Melting Time of 0.5 ml Ice Balls at NIR 808 nm, 1.31 W / cm 2 When)]]> <![CDATA[Infrared light reflectance / transmittance of hydrophobic modified fabric loaded with Ag2S]]> 1 Thioacetamide 62.3% 30s 6.3% / 1.5% 2 Sodium sulfide 58.1% 33s 8.7% / 2.3% 3 Thiourea 63.4% 27s 5.5% / 1.1% This example fully demonstrates that hydrophobic modified fabrics loaded with Ag2S can be prepared for different sulfur sources, and the photothermal conversion efficiency and infrared light shielding effect are both good, which fully demonstrates that this patent has universality regarding the types of sulfur sources.

[0042] According to the technical solution of the present invention, 0.5g of dopamine hydrochloride and 0.8g of hexadecyltrimethoxysilane are added to a 250ml beaker, 100ml of water is added to the beaker, and the beaker is sonicated for 30min to form a homogeneous transparent solution.

[0043] Pour the solution into a glass petri dish containing a 10cm*10cm fabric, completely immersing the wool fabric in the liquid; place the petri dish in a 25℃ oven for 3 days, turning it over every 10 hours and then removing it; wash the wool surface with running water for 3 minutes, and then place it in a 50℃ oven to dry for 24 hours to obtain the hydrophobic modified wool fabric.

[0044] Prepare a 10 mmol / L solution using 400 mg of AgNO3. Add PVP-K27 to the AgNO3 solution at a PVP / AgNO3 molar ratio of 1:1 and stir magnetically in the dark until dissolved. Add 30 ml of a 30 mmol / L NaHCO3 solution to form a milky white solution. Immerse a hydrophobically modified wool fabric (10 cm * 10 cm) in the prepared solution and continue stirring magnetically in the dark for 12 hours.

[0045] Prepare a 50 mmol / L thioacetamide solution, add 30 ml of the solution, and react with magnetic stirring at 25 °C for 3 days under light-protected conditions. Then wash the wool surface with running water for 3 min and dry it in a 30 °C oven for 48 h to obtain the hydrophobic modified fabric loaded with Ag2S.

[0046] According to the technical solution of the present invention, 3g of dopamine hydrochloride and 5.5g of hexadecyltrimethoxysilane are added to a 250ml beaker, 100ml of water is added to the beaker, and the beaker is sonicated for 30min to form a homogeneous transparent solution.

[0047] Pour the solution into a glass petri dish containing a 10cm*10cm fabric, completely immersing the wool fabric in the liquid; place the petri dish in a 60℃ oven for 1 day, turning it over every 15 hours and then removing it; wash the wool surface with running water for 3 minutes, and then place it in a 50℃ oven to dry for 24 hours to obtain the hydrophobic modified wool fabric.

[0048] Prepare a 50 mmol / L solution of AgNO3 with 500 mg of AgNO3. Add PVP-K27 to the AgNO3 solution according to the PVP / AgNO3 molar ratio of 2:1. Stir magnetically under dark conditions until dissolved. Add 30 ml of 80 mmol / L NaHCO3 solution to form a milky white solution. Immerse the hydrophobically modified wool fabric (10 cm * 10 cm) in the above-prepared solution and continue to stir magnetically under dark conditions for 24 h.

[0049] Prepare a 50 mmol / L thioacetamide solution, add 30 ml of the solution, and react with magnetic stirring at 50 °C for 1 day under light-protected conditions. Then wash the wool surface with running water for 3 min and dry it in a 50 °C oven for 24 h to obtain the hydrophobic modified fabric loaded with Ag2S.

[0050] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a flexible fabric with photothermal conversion and infrared shielding properties, characterized in that, Includes the following steps: (1) Mix dopamine hydrochloride with alkylsiloxane, then add water and stir until homogeneous and transparent solution is obtained; (2) Immerse the flexible fabric in the transparent solution, and then rinse it with water until unreacted dopamine hydrochloride and alkylsiloxane are removed to obtain the modified fabric. (3) Take AgNO3 solution, add PVP to it, stir until dissolved under light-protected conditions, then add NaHCO3 solution until a milky white solution is formed; then soak the modified fabric in the milky white solution and continue stirring under light-protected conditions to obtain a mixture; (4) Take the sulfur source solution and add it to the mixture in step (3). Stir the mixture under light-protected conditions. After the reaction is complete, wash with water to remove unreacted monomers and then dry to obtain a flexible fabric with photothermal conversion and infrared shielding properties.

2. The method for preparing the flexible fabric with photothermal conversion and infrared shielding properties according to claim 1, characterized in that, The method is as follows: (1) Mix 0.5-3 parts by weight of dopamine hydrochloride with 0.8-5.5 parts by weight of alkylsiloxane, then add water and stir until homogeneous to obtain a transparent solution; (2) Immerse the flexible fabric in the transparent solution for soaking reaction, and after the reaction, wash with water until unreacted dopamine hydrochloride and alkylsiloxane are removed to obtain the modified fabric; (3) Take 0.4-0.5 parts by mass of AgNO3 and add water to prepare an AgNO3 solution with a concentration of 10-50 mmol / L. Add PVP to the AgNO3 solution at a molar ratio of PVP:AgNO3 of 1-2:1 and stir under light-protected conditions until dissolved to obtain a mixed solution. Then, prepare 0.1-0.2 parts by mass of NaHCO3 to prepare a NaHCO3 solution with a concentration of 30-80 mmol / L and add it to the mixed solution to obtain a milky white solution. Finally, immerse the modified fabric in the milky white solution and continue stirring under light-protected conditions to obtain a mixture. (4) Take 0.113 parts by mass of sulfur source to prepare a sulfur source solution with a concentration of 30-80 mmol / L, and then add it to the mixture in step (3). Stir and react under light-protected conditions. After the reaction is completed, wash with water to remove unreacted monomers, and then dry to obtain a flexible fabric with photothermal conversion and infrared shielding properties.

3. The method for preparing a flexible fabric with photothermal conversion and infrared shielding properties according to claim 1 or 2, characterized in that: The flexible fabric is one of wool fabric, cotton fabric or polyester fabric.

4. The method for preparing the flexible fabric with photothermal conversion and infrared shielding properties according to claim 3, characterized in that: The wool fabrics include pure wool fabrics and blends of wool with cotton, polyester, spandex, nylon, acrylic, silk, or linen; the cotton fabrics include pure cotton fabrics or blends of cotton with polyester, spandex, acrylic, viscose fiber, silk, or linen; the polyester fabrics include pure polyester fabrics and blends of polyester with wool, cotton, spandex, acrylic, viscose fiber, silk, or linen.

5. The method for preparing a flexible fabric with photothermal conversion and infrared shielding properties according to claim 1 or 2, characterized in that: The alkylsiloxane is one of dodecyltrimethoxysilane, tetradecyltrichlorosilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, or octadecyltrimethoxysilane.

6. The method for preparing a flexible fabric with photothermal conversion and infrared shielding properties according to claim 1 or 2, characterized in that: The sulfur source solution is one of thioacetamide solution, sodium sulfide solution, or thiourea solution.

7. The method for preparing the flexible fabric with photothermal conversion and infrared shielding properties according to claim 2, characterized in that: The soaking reaction in step (2) is carried out at a temperature of 25-60℃ for 1-3 days, with the surface turned over every 10-15 hours.

8. The method for preparing the flexible fabric with photothermal conversion and infrared shielding properties according to claim 2, characterized in that: After the modified fabric in step (3) is soaked in the milky white solution, it is stirred for 6-24 hours under light-protected conditions.

9. The method for preparing the flexible fabric with photothermal conversion and infrared shielding properties according to claim 2, characterized in that: The stirring reaction in step (4) is carried out at a temperature of 25-50℃ for 1-3 days; the drying temperature is 30-50℃ for 24-48 hours.

10. A flexible fabric with photothermal conversion and infrared shielding properties prepared by the method according to any one of claims 1-9.

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