A polyurethane-based cool-feeling composition, method of making, and cool-feeling thin layer fabric

Abstract

The application relates to the technical field of high polymer materials, and discloses a polyurethane-based cool feeling composition, a preparation method and a cool feeling thin layer fabric. A microcapsule type heat-conducting cool feeling additive with peppermint oil and enhanced heat conduction performance is prepared, the heat-conducting material is introduced into imidazolium salt modified polyurethane with antibacterial performance, the prepared polyurethane composition has improved heat-conducting cool feeling performance due to the effect of the heat-conducting network; meanwhile, the peppermint oil and the imidazolium salt structure in the polyurethane endow the polyurethane composition with antibacterial effect, so that the fabric finished by the polyurethane composition has both heat-conducting cool feeling and antibacterial performance.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a polyurethane-based cooling composition, its preparation method, and a cooling thin-layer fabric. Background Technology

[0002] With global climate change and the increasing frequency of hot summers, consumer demand for textiles with a cooling sensation is growing. When human skin comes into contact with fabric that is cooler than its surface temperature, heat transfer occurs due to the temperature difference between the fabric and the skin. The heat on the skin surface is quickly dissipated, causing the skin surface temperature to drop and producing a cooling sensation.

[0003] Cooling finishes refer to surface modifications of fabrics, including the addition of cooling agents containing inorganic or organic cooling factors, to increase the thermal conductivity and heat dissipation of textiles, thus providing a cooling sensation and improving wearing comfort. Based on the principle behind the cooling effect, finishing agents can be divided into three categories: first, moisture-wicking finishing to improve the moisture absorption and wicking properties of synthetic fibers, keeping fabrics dry and comfortable; second, adding inorganic nanoparticles to enhance the thermal conductivity of fabrics; and third, improving the specific heat capacity of fabrics, such as through the use of phase change materials, to give fabrics a two-way temperature regulation function.

[0004] However, although inorganic thermally conductive fillers have high thermal conductivity, they are difficult to disperse uniformly and stably in polyurethane polymer finishing agents and have poor wash resistance. Secondly, although natural cooling agents such as peppermint oil can provide a continuous cooling sensation, they are highly volatile and have poor thermal stability. They are easily lost during processing when directly added to the finishing solution, and their water wash resistance is insufficient. In addition, although conventional polyurethane as a fabric finishing agent has good film-forming properties and flexibility, its intrinsic thermal conductivity is poor, and its performance needs to be improved through composite modification.

[0005] Therefore, developing a polyurethane composition that simultaneously possesses multiple functions such as high-efficiency thermal conductivity, long-lasting cooling release, and antibacterial properties, thereby enabling it to exhibit good adhesion and washability on fabric surfaces, is of significant application value. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a polyurethane-based cooling composition, a preparation method, and a cooling thin-layer fabric. By preparing a microcapsule-type thermally conductive and cooling additive containing peppermint oil and enhanced thermal conductivity, this additive is introduced together with a thermally conductive material into an imidazolium salt-modified polyurethane with antibacterial properties. The resulting polyurethane composition exhibits improved thermal conductivity and cooling properties due to the thermally conductive network effect. Simultaneously, the peppermint oil and the imidazolium salt structure in the polyurethane impart antibacterial effects to the polyurethane composition, resulting in a fabric treated with the polyurethane composition that possesses both thermal conductivity and antibacterial properties.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for preparing a polyurethane-based cooling composition includes the following steps: Step (1): Prepare thermally conductive cooling additives and thermally conductive fillers; The thermally conductive cooling additive is prepared by the following steps: S11. Adjust the pH value of the aluminum sulfate aqueous solution, react, and after the reaction is completed, the precursor is obtained; The precursor was filtered, washed until neutral, dried, and calcined. After calcination, it was ground and sieved to obtain flake alumina. S12. Mix flake alumina, ethanol, and water, add KH550, disperse by ultrasonication, and react. After the reaction is complete, filter, wash, and dry to obtain KH550 modified flake alumina. S13. KH550 modified flake alumina, isophorone diisocyanate, isocyanate methacrylate, and peppermint oil are mixed evenly to obtain the oil phase. Polyvinyl alcohol is dissolved in water to prepare a polyvinyl alcohol aqueous solution. An oil phase is added, and the mixture is emulsified. A diethylenetriamine aqueous solution is added dropwise, and the reaction is carried out. After the reaction is completed, the mixture is filtered, washed, and dried to obtain a thermally conductive and cooling additive. The thermally conductive filler is prepared by the following steps: S21. Carbon nanotubes are added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid to acidify them. After acidification, they are washed and dried to obtain acidified carbon nanotubes. S22. KH550 modified sheet alumina and acidified carbon nanotubes were added to isopropanol, ultrasonically dispersed, and reacted. After the reaction was completed, the mixture was filtered, washed, and dried to obtain a thermally conductive filler. Step (2): Prepare a polyurethane-based cooling composition; N-allyl imidazole, dibromoneopentyl glycol, and dimethyl sulfoxide were mixed and reacted. After the reaction was completed, the mixture was purified to obtain the imidazole onium salt chain extender. Polyethylene glycol and isophorone diisocyanate were mixed and reacted. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued. After the reaction was completed, the mixture was cooled and discharged to obtain imidazolium salt modified polyurethane. A cooling composition is obtained by mixing imidazolium salt-modified polyurethane, thermally conductive cooling additives, and thermally conductive fillers.

[0008] Preferably, in step (1), when preparing the thermally conductive cooling additive, in S11: the concentration of aluminum sulfate aqueous solution is 1 mol / L; the adjusted pH value is 9; the reaction conditions are: reacting at 230-280℃ for 36-52 h; and the calcination conditions are: calcining at 550-600℃ for 4-5 h.

[0009] Preferably, in step (1), when preparing the thermally conductive cooling additive, the ratio of sheet alumina, ethanol, water and KH550 in S12 is 1g:50-60mL:40-50mL:0.1-0.2g; the reaction conditions are: reacting at 50-60℃ for 24-48h.

[0010] Preferably, in step (1), when preparing the thermally conductive cooling additive, in S13: the mass ratio of KH550 modified flake alumina, isophorone diisocyanate, isocyanate methacrylate, and peppermint oil is 0.5:3.5-4:0.1-0.5:12; the ratio of oil phase, polyvinyl alcohol aqueous solution, and diethylenetriamine aqueous solution is 16-17g:50-60mL:50-60mL; the concentration of polyvinyl alcohol aqueous solution is 1-10wt%, and the concentration of diethylenetriamine aqueous solution is 1-5wt%.

[0011] Preferably, in step (1), when preparing the thermally conductive cooling additive, the reaction conditions in S13 are: reacting at a temperature of 60-80℃ for 1-4 hours.

[0012] Preferably, in step (1), when preparing the thermally conductive filler, the ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid in S21 is 1g:20-35mL:10mL; the acidification conditions are: stirring and acidifying at 35-45℃ for 8-12 hours.

[0013] Preferably, in step (1), when preparing the thermally conductive filler, the ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol in S21 is 0.1g:0.8-1g:900-1000mL; the KH550 modified sheet alumina is prepared in step (1) S11; the reaction conditions are: stirring at 60-70℃ for 10-12h.

[0014] Preferably, in step (2), when preparing the imidazolium salt chain extender, the ratio of N-allyl imidazolium, dibromoneopentyl glycol, and dimethyl sulfoxide is 2.3-2.7 g: 2.62: 50 mL; the reaction conditions are: reaction at 120-130 °C for 24-28 h in a nitrogen atmosphere.

[0015] Preferably, in step (2), when preparing the imidazolium salt chain extender, the purification operation includes: rotary evaporation concentration, adding a precipitant to precipitate, washing the precipitate with tetrahydrofuran, and drying; wherein the precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4-6.

[0016] Preferably, in step (2), when preparing imidazolium salt modified polyurethane: the molar ratio of polyethylene glycol to isophorone diisocyanate is 1:2-2.2; the mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 60-62:19-23; the reaction conditions and the conditions for continued reaction are: reaction at 70-85℃ for 1-2 hours.

[0017] Preferably, in step (2), the mass ratio of imidazole-onium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler is 70-80:20-30:5-7.

[0018] Preferably, a polyurethane-based cooling composition is prepared using the method described above for preparing a polyurethane-based cooling composition.

[0019] Preferably, the application of the polyurethane-based cooling composition as described above in a cooling thin-layer fabric, wherein the method for preparing the cooling thin-layer fabric is as follows: The polyurethane-based cooling composition, photoinitiator, emulsifier, and water prepared above were mixed to form a finishing solution. The washed polyester thin-layer fabric was immersed in the finishing solution at a liquor ratio of 1:20, with two dips and two nips, and a liquid retention rate of 60-80%. After immersion and nipping, the fabric was taken out and pre-dried at 60-70℃ for 50-60s. It was then placed in a UV curing oven for 60-110s for light irradiation. After the reaction was completed, the fabric was taken out and baked at 120-130℃ for 1-3min. After cooling, the cooling thin-layer fabric was obtained. The concentration of the polyurethane-based cooling composition in the finishing solution is 70-110 g / L, the concentration of the photoinitiator is 0.5-1.5 wt%, and the concentration of the emulsifier is 5-10 wt%.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention prepares a microcapsule-type thermally conductive and cooling additive containing peppermint oil and enhanced thermal conductivity. This additive is then introduced together with a thermally conductive material into an imidazolium salt-modified polyurethane with antibacterial properties. The resulting polyurethane composition exhibits improved thermal conductivity and cooling properties due to the thermally conductive network. Simultaneously, the peppermint oil and the imidazolium salt structure in the polyurethane impart antibacterial effects to the polyurethane composition, resulting in fabrics treated with the polyurethane composition possessing both thermal conductivity and cooling properties as well as antibacterial properties.

[0021] This invention produces inorganic thermally conductive sheet alumina by controlling the hydrothermal reaction temperature and pH value. After surface modification with amino groups using KH550, it is introduced into microcapsule-type thermally conductive cooling additives as a crosslinking component and thermally conductive material, thereby improving the thermal conductivity of the microcapsule wall material and enhancing the thermal stability and mechanical properties of the microcapsules. This invention utilizes the reaction of N-allyl imidazole with dibromoneopentyl glycol to obtain an imidazole onium salt chain extender containing a dihydroxyl structure. The imidazole onium salt is a class of compounds with antibacterial activity, and its chemical structure includes an imidazole ring and a quaternary ammonium salt group, both of which have antibacterial properties. The imidazole onium salt chain extender is introduced into polyurethane to impart antibacterial properties to the polyurethane matrix. This invention reacts KH550 modified flake alumina with acidified carbon nanotubes to form a thermally conductive filler. This filler, along with a thermally conductive cooling additive, is then introduced into imidazolium salt modified polyurethane to obtain a polyurethane-based cooling composition. After this composition is formulated into a fabric finishing liquid and the fabric is finished, the carbon-carbon double bonds in the imidazolium salt modified polyurethane will react and crosslink under light conditions, improving the adhesion of functional components to the fabric surface and enhancing the fabric's wash resistance. Meanwhile, the hydrophilic polyether segments and quaternary ammonium salt groups in imidazolium salt-modified polyurethane improve its hydrophilic moisture absorption properties, thereby further enhancing the fabric's cooling effect by improving its moisture absorption and thermal conductivity. Attached Figure Description

[0022] Figure 1 This is a bar chart showing the antibacterial rate of the cooling thin-layer fabrics prepared in Example 6 and Comparative Example 3 of this invention during performance testing; Figure 2 This is a line graph showing the thermal conductivity of the cooling thin-layer fabrics prepared in Example 6 and Comparative Example 3 of this invention during performance testing. Figure 3 This is a line graph showing the contact cooling coefficient of the cooling thin-layer fabrics prepared in Example 6 and Comparative Example 3 of this invention during performance testing; Figure 4 This is a schematic diagram of the reaction for preparing imidazolium salt chain extenders in this invention. Detailed Implementation

[0023] The present invention will be further illustrated below through specific embodiments. The following embodiments are specific implementations of the present invention, but the implementation of the present invention is not limited to the following embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and are included within the protection scope of the present invention.

[0024] Example 1 This embodiment discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.1g; Step (2): KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil are mixed evenly in a mass ratio of 0.5:4:0.1:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a thermally conductive cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 16 g: 60 mL: 50 mL. Step (3): N-allyl imidazole, neopentyl dibromodiol, and dimethyl sulfoxide were mixed in a ratio of 2.3g:2.62:50mL and reacted at 130℃ for 24h under a nitrogen atmosphere. After the reaction was completed, the mixture was concentrated by rotary evaporation, and a precipitant was added to precipitate the product. The precipitate was washed with tetrahydrofuran and dried at 40℃ for 12h to obtain imidazole onium salt chain extender. The precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4. Polyethylene glycol and isophorone diisocyanate were mixed in a molar ratio of 1:2 and reacted at 85°C for 1 hour. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued at 70°C for 2 hours. After the reaction was completed, the material was cooled and discharged to obtain imidazolium salt modified polyurethane. The mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 60:19. Step (4): Mix imidazolium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler at a mass ratio of 70:30:5 to obtain a polyurethane-based cooling composition. The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0025] Example 2 This embodiment discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.13g. Step (2): KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil are mixed evenly in a mass ratio of 0.5:3.6:0.2:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a thermally conductive cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 16.3 g: 60 mL: 53 mL. Step (3): N-allyl imidazole, dibromoneopentyl glycol, and dimethyl sulfoxide were mixed in a ratio of 2.4 g: 2.62: 50 mL and reacted at 130 °C for 24 h under a nitrogen atmosphere. After the reaction was completed, the mixture was concentrated by rotary evaporation, and a precipitant was added to precipitate the mixture. The precipitate was washed with tetrahydrofuran and dried at 40 °C for 12 h to obtain imidazole onium salt chain extender. The precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4. Polyethylene glycol and isophorone diisocyanate were mixed in a molar ratio of 1:2 and reacted at 85°C for 1 hour. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued at 70°C for 2 hours. After the reaction was completed, the material was cooled and discharged to obtain imidazolium salt modified polyurethane. The mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 60.5:20. Step (4): Mix imidazolium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler at a mass ratio of 73:27:5.5 to obtain a polyurethane-based cooling composition; The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0026] Example 3 This embodiment discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.15g. Step (2): KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil are mixed evenly in a mass ratio of 0.5:3.8:0.3:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a thermally conductive cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 16.5 g: 60 mL: 55 mL. Step (3): N-allyl imidazole, dibromoneopentyl glycol, and dimethyl sulfoxide were mixed in a ratio of 2.5g:2.62:50mL and reacted at 130℃ for 24h under a nitrogen atmosphere. After the reaction was completed, the mixture was concentrated by rotary evaporation, and a precipitant was added to precipitate the product. The precipitate was washed with tetrahydrofuran and dried at 40℃ for 12h to obtain imidazole onium salt chain extender. The precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4. Polyethylene glycol and isophorone diisocyanate were mixed in a molar ratio of 1:2 and reacted at 85°C for 1 hour. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued at 70°C for 2 hours. After the reaction was completed, the material was cooled and discharged to obtain imidazolium salt modified polyurethane. The mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 61:21. Step (4): Mix imidazole-onium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler at a mass ratio of 75:25:6 to obtain a polyurethane-based cooling composition; The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0027] Example 4 This embodiment discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.18g. Step (2): KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil are mixed evenly in a mass ratio of 0.5:3.9:0.4:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a thermally conductive cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 16.8 g: 60 mL: 58 mL. Step (3): N-allyl imidazole, dibromoneopentyl glycol, and dimethyl sulfoxide were mixed in a ratio of 2.6g:2.62:50mL and reacted at 130℃ for 24h under a nitrogen atmosphere. After the reaction was completed, the mixture was concentrated by rotary evaporation, and a precipitant was added to precipitate the product. The precipitate was washed with tetrahydrofuran and dried at 40℃ for 12h to obtain imidazole onium salt chain extender. The precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4. Polyethylene glycol and isophorone diisocyanate were mixed in a molar ratio of 1:2 and reacted at 85°C for 1 hour. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued at 70°C for 2 hours. After the reaction was completed, the material was cooled and discharged to obtain imidazolium salt modified polyurethane. The mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 61.5:22. Step (4): Mix imidazole-onium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler at a mass ratio of 78:22:6.5 to obtain a polyurethane-based cooling composition; The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0028] Example 5 This embodiment discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.2g. Step (2): KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil are mixed evenly in a mass ratio of 0.5:3.5:0.5:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a thermally conductive cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 17 g: 60 mL: 60 mL. Step (3): N-allyl imidazole, dibromoneopentyl glycol, and dimethyl sulfoxide were mixed in a ratio of 2.7g:2.62:50mL and reacted at 130℃ for 24h under a nitrogen atmosphere. After the reaction was completed, the mixture was concentrated by rotary evaporation, and a precipitant was added to precipitate the product. The precipitate was washed with tetrahydrofuran and dried at 40℃ for 12h to obtain imidazole onium salt chain extender. The precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4. Polyethylene glycol and isophorone diisocyanate were mixed in a molar ratio of 1:2 and reacted at 85°C for 1 hour. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued at 70°C for 2 hours. After the reaction was completed, the material was cooled and discharged to obtain imidazolium salt modified polyurethane. The mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 62:23. Step (4): Mix imidazolium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler at a mass ratio of 80:20:7 to obtain a polyurethane-based cooling composition; The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0029] Example 6 This embodiment discloses a method for preparing a cooling-feel thin-layer fabric, including the following steps: The polyurethane-based cooling compositions prepared in Examples 1-5 were mixed with photoinitiator 1173, emulsifier DNS-86, and water, and emulsified to obtain a cooling finishing liquid. The concentration of the polyurethane-based cooling composition is 100 g / L, the concentration of the photoinitiator is 1 wt%, and the concentration of the emulsifier is 10 wt%. The washed polyester thin-layer fabric was immersed in a cooling finishing solution at a liquor ratio of 1:20, with two dips and two nips, and a liquid retention rate of 70%. After immersion and nipping, the fabric was removed and pre-dried at 60°C for 60 seconds. It was then placed in a UV curing chamber for 100 seconds of light exposure. After the reaction was completed, the fabric was removed and baked at 120°C for 3 minutes. After cooling, the cooling thin-layer fabric was obtained and recorded as samples 1-5.

[0030] Comparative Example 1 This comparative example discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.1g; Step (2): KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil are mixed evenly in a mass ratio of 0.5:4:0.1:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a thermally conductive cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 16 g: 60 mL: 50 mL. Step (3): Mix polyethylene glycol and isophorone diisocyanate and react at 85°C for 1 hour. After the reaction is complete, a polyurethane prepolymer is obtained. Add ethylene glycol to the polyurethane prepolymer and continue to react at 70°C for 2 hours. After the reaction is complete, cool down and discharge the material to obtain polyurethane. The molar ratio of polyethylene glycol, isophorone diisocyanate, and ethylene glycol is 1:2:1. Step (4): Mix polyurethane, thermally conductive cooling additive, and thermally conductive filler at a mass ratio of 70:30:5 to obtain a polyurethane-based cooling composition; The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0031] Comparative Example 2 This comparative example discloses a method for preparing a polyurethane-based cooling composition, comprising the following steps: Step (1): Prepare a 1 mol / L aluminum sulfate aqueous solution with aluminum sulfate and water, add ammonia to adjust the pH to 9, transfer to a muffle furnace, and react at 250℃ for 48 h. After the reaction is completed, the precursor is obtained. The precursor was washed with water until neutral, dried at 60°C for 12 hours, transferred to a muffle furnace, and calcined at 600°C for 4 hours. After calcination, it was ground and sieved to obtain flake alumina. Flake alumina, ethanol, and water were mixed, KH550 was added, and the mixture was ultrasonically dispersed for 30 min. The mixture was then reacted at 60℃ for 24 h. After the reaction was completed, the mixture was filtered, washed with ethanol and water, and dried at 60℃ for 12 h to obtain KH550 modified flake alumina. The ratio of flake alumina, ethanol, water, and KH550 is 1g:50mL:50mL:0.1g; Step (2): Mix isophorone diisocyanate, isocyanate methacrylate, and peppermint oil in a mass ratio of 4:0.1:12 to obtain the oil phase; Polyvinyl alcohol was dissolved in water to prepare a 5 wt% polyvinyl alcohol aqueous solution. The solution was heated to 70°C and stirred at 600 r / min for 30 min. The oil phase was added and emulsified for 4 min. A 3 wt% diethylenetriamine aqueous solution was added dropwise and reacted at 70°C for 2 h. After the reaction was completed, the solution was filtered, washed with water, and dried at 50°C for 12 h to obtain a cooling additive. The ratio of oil phase, 5 wt% polyvinyl alcohol aqueous solution, and 3 wt% diethylenetriamine aqueous solution was 16 g: 60 mL: 50 mL. Step (3): N-allyl imidazole, neopentyl dibromodiol, and dimethyl sulfoxide were mixed in a ratio of 2.3g:2.62:50mL and reacted at 130℃ for 24h under a nitrogen atmosphere. After the reaction was completed, the mixture was concentrated by rotary evaporation, and a precipitant was added to precipitate the product. The precipitate was washed with tetrahydrofuran and dried at 40℃ for 12h to obtain imidazole onium salt chain extender. The precipitant is prepared by mixing petroleum ether and tetrahydrofuran in a volume ratio of 1:4. Polyethylene glycol and isophorone diisocyanate were mixed in a molar ratio of 1:2 and reacted at 85°C for 1 hour. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued at 70°C for 2 hours. After the reaction was completed, the material was cooled and discharged to obtain imidazolium salt modified polyurethane. The mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 60:19. Step (4): Mix imidazolium salt modified polyurethane, cooling additive, and thermally conductive filler at a mass ratio of 70:30:5 to obtain a polyurethane-based cooling composition; The thermally conductive filler is prepared by the following steps: Carbon nanotubes were added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid and stirred at 40°C for 10 hours. After acidification, the carbon nanotubes were washed with water until neutral and then freeze-dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:30mL:10mL. The KH550 modified sheet alumina and acidified carbon nanotubes prepared in step (1) were added to isopropanol, ultrasonically dispersed, stirred and reacted at 70°C for 10 h, filtered after the reaction was completed, washed with water, and dried at 50°C for 12 h to obtain thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8g:900mL.

[0032] Comparative Example 3 This comparative example discloses a method for preparing a cooling thin-layer fabric, including the following steps: The polyurethane-based cooling composition prepared in Comparative Examples 1-2 was mixed with photoinitiator 1173, emulsifier DNS-86, and water, and emulsified to obtain a cooling finishing liquid. The concentration of the polyurethane-based cooling composition is 100 g / L, the concentration of the photoinitiator is 1 wt%, and the concentration of the emulsifier is 10 wt%. The washed polyester thin-layer fabric was immersed in a cooling finishing solution at a liquor ratio of 1:20, with two dips and two nips, and a liquid retention rate of 70%. After immersion and nipping, the fabric was removed and pre-dried at 60°C for 60 seconds. It was then placed in a UV curing oven for 100 seconds of light exposure. After the reaction was completed, the fabric was removed and baked at 120°C for 3 minutes. After cooling, the cooling thin-layer fabric was obtained and designated as sample 6-7.

[0033] In the above examples and comparative examples: KH550 is γ-aminopropyltriethoxysilane; peppermint oil is commercially available; polyvinyl alcohol is PVA1788; polyethylene glycol is PEG2000; and the polyester thin-layer fabric is a polyester thin-layer knitted fabric with a weight of 90 g / m2.

[0034] Test case The cooling thin-layer fabrics prepared in Example 6 and Comparative Example 3 were subjected to performance tests. Specific test results are shown in Table 1. Table 1

[0035] The tests for each indicator in Table 1 were conducted according to the following standards: Antibacterial rate was determined according to GB / T20944.3 "Evaluation of Antibacterial Properties of Textiles - Part 3: Shaking Method", with *Escherichia coli* as the bacterial strain; thermal conductivity was measured using a thermal conductivity meter; contact cooling coefficient was determined according to GB / T35263 "Test and Evaluation of Instantaneous Cooling Properties of Textiles"; washability was expressed as mass loss rate, tested according to standard GB / T 12490 "Tests on Color Fastness of Textiles - Color Fastness to Household and Commercial Washing"; the number of washes was 10; the test method for fabric mass loss rate was: Mass loss rate (%) = (Δm2 / Δm1) × 100%; where: Δm1 is the mass difference (g) of the fabric before and after finishing; Δm2 is the mass difference (g) of the finished fabric before and after washing.

[0036] As can be seen from the test results in Table 1, the fabric treated with the polyurethane-based cooling composition prepared by the present invention has excellent thermal conductivity and cooling properties, good antibacterial effect, and long-lasting function.

[0037] In Comparative Example 1, when preparing the polyurethane-based cooling composition, the imidazole onium salt chain extender was replaced with the common chain extender ethylene glycol. Because the imidazole onium salt structure possesses an imidazole ring and quaternary ammonium salt groups with antibacterial activity, and the double bonds in the imidazole onium salt structure contribute to increased crosslinking density during photocuring, the antibacterial and washability properties of Sample 6 prepared based on Comparative Example 2 were reduced. Comparative Example 2 microcapsules did not contain KH550-modified flake alumina. As a highly thermally conductive inorganic material, flake alumina, after surface modification with KH550, can participate in the crosslinking reaction of the microcapsule wall material, improving the thermal conductivity and mechanical stability of the wall material. Therefore, the absence of KH550-modified flake alumina reduced the thermal conductivity of the microcapsules, thus affecting the overall cooling effect of the fabric.

[0038] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing a polyurethane-based cooling composition, characterized in that, Includes the following steps: Step (1): Mix N-allyl imidazole, dibromoneopentyl glycol, and dimethyl sulfoxide, react, and after the reaction is complete, purify to obtain imidazole onium salt chain extender; Polyethylene glycol and isophorone diisocyanate were mixed and reacted. After the reaction was completed, a polyurethane prepolymer was obtained. Imidazolium salt chain extender was added to the polyurethane prepolymer and the reaction was continued. After the reaction was completed, the mixture was cooled and discharged to obtain imidazolium salt modified polyurethane. Step (2): Mix the imidazolium salt modified polyurethane, the thermally conductive cooling additive, and the thermally conductive filler to obtain the cooling composition.

2. The method for preparing a polyurethane-based cooling composition according to claim 1, characterized in that, In step (1), when preparing the imidazolium salt chain extender, the ratio of N-allyl imidazolium, dibromoneopentyl glycol, and dimethyl sulfoxide is 2.3-2.7 g: 2.62: 50 mL; the reaction conditions are: reaction at 120-130 °C for 24-28 h in a nitrogen atmosphere.

3. The method for preparing a polyurethane-based cooling composition according to claim 1, characterized in that, In step (1), when preparing imidazolium salt modified polyurethane: the molar ratio of polyethylene glycol to isophorone diisocyanate is 1:2-2.2; the mass ratio of polyurethane prepolymer to imidazolium salt chain extender is 60-62:19-23; the reaction conditions and the conditions for continued reaction are: reaction at 70-85℃ for 1-2 hours.

4. The method for preparing a polyurethane-based cooling composition according to claim 1, characterized in that, In step (2), the mass ratio of imidazolium salt modified polyurethane, thermally conductive cooling additive, and thermally conductive filler is 70-80:20-30:5-7.

5. The method for preparing a polyurethane-based cooling composition according to claim 1, characterized in that, The thermally conductive cooling additive in step (2) is prepared by the following steps: S11. Adjust the pH value of the aluminum sulfate aqueous solution, react, and after the reaction is completed, the precursor is obtained; The precursor was filtered, washed until neutral, dried, and calcined. After calcination, it was ground and sieved to obtain flake alumina. S12. Mix flake alumina, ethanol, and water, add KH550, disperse by ultrasonication, and react. After the reaction is complete, filter, wash, and dry to obtain KH550 modified flake alumina. S13. KH550 modified flake alumina, isophorone diisocyanate, isocyanate methacrylate, and peppermint oil are mixed evenly to obtain the oil phase. Polyvinyl alcohol was dissolved in water to prepare a polyvinyl alcohol aqueous solution. An oil phase was added, and the mixture was emulsified. A diethylenetriamine aqueous solution was then added dropwise, and the mixture was allowed to react. After the reaction was completed, the mixture was filtered, washed, and dried to obtain a thermally conductive and cooling additive.

6. The method for preparing a polyurethane-based cooling composition according to claim 5, characterized in that, In step (2), when preparing the thermally conductive cooling additive, in S11: the concentration of aluminum sulfate aqueous solution is 1 mol / L; the adjusted pH value is 9; the reaction conditions are: reacting at 230-280℃ for 36-52 h; the calcination conditions are: calcining at 550-600℃ for 4-5 h. In S12, the ratio of sheet alumina, ethanol, water, and KH550 is 1g:50-60mL:40-50mL:0.1-0.2g; the reaction conditions are: reacting at 50-60℃ for 24-48h.

7. The method for preparing a polyurethane-based cooling composition according to claim 5, characterized in that, In step (2), when preparing the thermally conductive cooling additive, the mass ratio of KH550 modified flake alumina, isophorone diisocyanate, isocyanate methyl methacrylate, and peppermint oil in S13 is 0.5:3.5-4:0.1-0.5:12; the ratio of oil phase, polyvinyl alcohol aqueous solution, and diethylenetriamine aqueous solution is 16-17g:50-60mL:50-60mL; the concentration of polyvinyl alcohol aqueous solution is 1-10wt%, and the concentration of diethylenetriamine aqueous solution is 1-5wt%; the reaction conditions are: reacting at 60-80℃ for 1-4h.

8. The method for preparing a polyurethane-based cooling composition according to claim 1, characterized in that, The thermally conductive filler in step (2) is prepared by the following steps: S21. Carbon nanotubes are added to a mixed solvent of concentrated sulfuric acid and concentrated nitric acid to acidify them. After acidification, they are washed and dried to obtain acidified carbon nanotubes. The ratio of carbon nanotubes, concentrated sulfuric acid, and concentrated nitric acid is 1g:20-35mL:10mL; the acidification conditions are: stirring and acidifying at 35-45℃ for 8-12 hours. S22. KH550 modified sheet alumina and acidified carbon nanotubes were added to isopropanol, ultrasonically dispersed, and reacted. After the reaction was completed, the mixture was filtered, washed, and dried to obtain the thermally conductive filler. The ratio of KH550 modified sheet alumina, acidified carbon nanotubes, and isopropanol was 0.1g:0.8-1g:900-1000mL; the KH550 modified sheet alumina was the same as that added in the preparation of the thermally conductive cooling additive; the reaction conditions were: stirring at 60-70℃ for 10-12h.

9. A polyurethane-based cooling composition prepared by the method of preparing a polyurethane-based cooling composition according to any one of claims 1-8.

10. An application of the polyurethane-based cooling composition as described in claim 9 on a cooling thin-layer fabric, wherein the cooling thin-layer fabric is prepared by: The polyurethane-based cooling composition, photoinitiator, emulsifier, and water prepared above were mixed to form a finishing solution. The washed polyester thin-layer fabric was immersed in the finishing solution at a liquor ratio of 1:20, with two dips and two nips, and a liquid retention rate of 60-80%. After immersion and nipping, the fabric was taken out and pre-dried at 60-70℃ for 50-60s. It was then placed in a UV curing oven for 60-110s for light irradiation. After the reaction was completed, the fabric was taken out and baked at 120-130℃ for 1-3min. After cooling, the cooling thin-layer fabric was obtained. in, The concentration of the polyurethane-based cooling composition in the finishing solution is 70-110 g / L, the concentration of the photoinitiator is 0.5-1.5 wt%, and the concentration of the emulsifier is 5-10 wt%.

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