Thermal insulation and air-permeable layered composite fabric and preparation method thereof
By modifying cotton fabrics and PA6 fibers and finishing them with polyurethane emulsion, combined with polyester fiber filling, a layered composite fabric with heat insulation, breathability and flame retardancy properties was prepared, which solved the problem of reduced breathability caused by coatings and expanded the application scenarios.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHAOXING GOLD SUN TEXTILE CO LTD
- Filing Date
- 2026-04-15
- Publication Date
- 2026-06-12
AI Technical Summary
Existing textile fabrics have reduced breathability after being coated with heat-insulating coatings, affecting wearing comfort and making it difficult to simultaneously achieve both heat insulation and breathability.
By functionalizing cotton fabrics, modified PA6 fiber and polyurethane emulsion finished fabrics are prepared, and polyester fibers are filled between the inner layer and the modified outer layer to form a porous thermal insulation and breathable layered composite fabric.
This technology achieves a balance between thermal insulation and breathability in layered composite fabrics, while also possessing excellent flame-retardant properties, thus expanding its application range.
Smart Images
Figure CN122185681A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of layered composite fabric technology, specifically to a heat-insulating and breathable layered composite fabric and its preparation method. Background Technology
[0002] As people's living standards continue to improve, consumers' demands for textiles and clothing are also increasing. In the cold winter, people have higher requirements for the warmth of clothing and textile fabrics. For centuries, people have often chosen to improve the warmth of clothing and textile fabrics by combining fiber materials with heat-insulating coatings. However, in the process of applying heat-insulating coatings to fabrics, the coatings can block the pores in the fabric, leading to a decrease in the fabric's breathability and thus affecting people's wearing comfort. Therefore, how to simultaneously take into account the warmth and breathability of the fabric is an urgent problem to be solved. Summary of the Invention
[0003] To address the aforementioned technical problems, this invention provides a method for preparing a thermally insulating and breathable layered composite fabric, comprising the following steps: Step 1: Using phosphorus oxychloride and vinyl magnesium bromide as raw materials, prepare trivinyl phosphorus-containing compounds; then modify cotton fabrics with diethylenetriaminepropyltrimethoxysilane and trivinyl phosphorus-containing compounds to obtain functionalized cotton fabrics. Step 2: Using silica nanoparticles and 1,3,5-triethynyl-benzene as raw materials, polymer hollow nanospheres are prepared; chitosan is assembled on the surface of the polymer hollow nanospheres to obtain surface-modified polymer hollow nanospheres. Step 3: Prepare a polyurethane emulsion using diphenylmethylene diisocyanate, polyethylene glycol, and surface-modified polymer hollow nanospheres as the main raw materials; Step 4: Using polyethylene glycol as a pore-forming agent, mix it with PA6 particles and melt spin to prepare modified PA6 fibers; spin and knit the modified PA6 fibers to obtain the surface fabric; impregnate the surface fabric with polyurethane emulsion, bake, and cool to obtain the modified surface fabric. Step 5: Use functionalized cotton fabric as the inner layer, lay filling fibers between the inner layer and the modified outer layer, and sew them together to obtain a heat-insulating and breathable layered composite fabric.
[0004] Preferably, in step one, the method for preparing the functionalized cotton fabric is as follows: Take twice the dry weight of deionized water from the cotton fabric, add diethylenetriaminepropyltrimethoxysilane to obtain a pretreatment solution; apply the pretreatment solution onto the cotton fabric, and then dry it at 60°C for 20-40 minutes to obtain the pretreated cotton fabric; wherein the coating content in the pretreated cotton fabric is 3.42-6.84 wt%. Take twice the dry weight of the pretreated cotton fabric in deionized water, add a trivinyl phosphorus compound to it to obtain a modification treatment solution; apply the modification treatment solution to the pretreated cotton fabric, dry it at 58-62℃ for 10-20 min, then modify it under steam at 100℃ for 20-40 min, and wash the modified cotton fabric with water at 38-42℃ 2-4 times, each time for 2-4 min, to obtain a functionalized cotton fabric; wherein the total content of the coating in the functionalized cotton fabric is 8-17 wt%.
[0005] In the above process, the silanol groups generated by the hydrolysis of diethylenetriaminepropyltrimethoxysilane undergo a condensation reaction with the hydroxyl groups of the cotton fabric to obtain a pretreated cotton fabric grafted with diethylenetriaminepropyltrimethoxysilane. Then, the trivinyl phosphorus compound reacts with the unsaturated double bonds on the surface of the pretreated cotton fabric under vapor conditions to covalently graft the trivinyl phosphorus compound onto the pretreated cotton fabric, thereby obtaining a functionalized cotton fabric. The surface of the functionalized cotton fabric is chemically grafted with nitrogen, phosphorus, and silicon flame-retardant elements, giving the functionalized cotton fabric excellent flame-retardant properties. At the same time, compared with cotton fabric, the pore size of the functionalized cotton fabric surface is larger, thus improving its breathability.
[0006] Preferably, in step one, the preparation method of the trivinyl phosphorus-containing compound is as follows: Phosphorus oxychloride was dissolved in tetrahydrofuran, cooled to -70°C, and stirred under a nitrogen atmosphere. Then, a 1 mol / L tetrahydrofuran solution of vinyl magnesium bromide was added. After the addition was complete, the mixture was stirred at -68°C to -64°C for 2.5 to 3.5 hours. Then, 300 to 500 mL of a 4 mol / L ammonium chloride aqueous solution was added. After the reaction system returned to room temperature, the product was purified to obtain a trivinyl phosphorus-containing compound. The volume ratio of the phosphorus oxychloride solution, tetrahydrofuran, 1 mol / L tetrahydrofuran solution of vinyl magnesium bromide, and 4 mol / L ammonium chloride aqueous solution was (4.6 to 9.2):(150 to 300):(150 to 300):(300 to 500).
[0007] Preferably, in step one, the weight of the cotton fabric is 110-130 g / m². 2 .
[0008] Preferably, in step two, the preparation method of the polymer hollow nanospheres is as follows: Silica nanoparticles, toluene, triethylamine, and acetonitrile were mixed and sonicated. Then, 1,3,5-triethynylbenzene, cuprous iodide, and tetrakis(triphenylphosphine)palladium were added and sonicated. The mixture was then reacted at 76-80℃ for 64-72 h in a nitrogen atmosphere. The reaction product was washed and dried to obtain a solid powder. The solid powder was etched in an etching solution with a solid-liquid mass ratio of 1:(80-100), and allowed to stand for 5-7 hours to purify the product, thus obtaining polymer hollow nanospheres. The etching solution was obtained by mixing HF, methanol and deionized water in a volume ratio of 9:24:18.
[0009] Preferably, in the solid powder preparation process, the mass ratio of silica nanoparticles, toluene, triethylamine, acetonitrile, 1,3,5-triethynylbenzene, cuprous iodide, and tetrakis(triphenylphosphine)palladium is (21-42):(78.5-157):(65.5-131):(2-4):(0.9-1.8):(0.05-0.1):(0.1-0.2).
[0010] In the above process, 1,3,5-triethynyl-benzene is used as the polymer monomer to polymerize on the surface of silica nanoparticles, and then the silica nanoparticles are removed by etching solution to obtain polymer hollow nanospheres.
[0011] Preferably, in step two, the method for preparing the surface-modified polymer hollow nanospheres is as follows: Polymer hollow nanospheres were dispersed in deionized water and stirred. Acetic acid was added to adjust the pH of the solution to 6-6.4. Chitosan was then added, and the product was purified to obtain surface-modified polymer hollow nanospheres. The mass ratio of the polymer hollow nanospheres, deionized water and chitosan was (1-1.5):(500-600):(1.8-3.4).
[0012] In the above process, chitosan is assembled onto the surface of polymer hollow nanospheres using a self-assembly method to obtain surface-modified polymer hollow nanospheres. The hollow structure of the surface-modified polymer hollow nanospheres endows them with excellent thermal insulation properties. At the same time, during combustion, their hollow porous structure can adsorb flammable gases generated during combustion, thereby inhibiting the combustion of the matrix material. Furthermore, the nitrogen element provided by chitosan can not only release non-flammable gases at high temperatures and reduce the concentration of flammable gases, but also promote the formation of an expanded carbon layer. Therefore, the surface-modified polymer hollow nanospheres can serve as flame-retardant, thermal insulation, and functional fillers for polymer matrices.
[0013] Preferably, in step three, the polyurethane emulsion is prepared by: In a nitrogen atmosphere, diphenylmethylene diisocyanate and polyethylene glycol 2000 are mixed and stirred for 20-40 min. Then, dibutyltin dilaurate is added, and the mixture is reacted at 78-82℃ for 4-6 h. Next, surface-modified polymer hollow nanospheres are added, and the mixture is reacted at 40-50℃ for 2-3 h. Then, 1,4-butanediol is added, and the mixture is stirred for 4-5 min. Finally, 1,3-dioxolane is added, and the mixture is stirred for another 15-25 min until the NCO content in the reaction system is less than 0.5%. The solvent is evaporated, and then deionized water is added and emulsified to obtain a polyurethane emulsion with a solid content of 20-30 wt%; wherein the mass ratio of diphenylmethylene diisocyanate, polyethylene glycol 2000, dibutyltin dilaurate, surface-modified polymer hollow nanospheres, 1,4-butanediol, and 1,3-dioxane is (5.55-11.1):(25-45):(0.02-0.06):(0.9-1.7):(9-18):(100-200).
[0014] In the above process, the amino and hydroxyl groups introduced by chitosan on the surface-modified polymer hollow nanospheres can react with isocyanate groups during polyurethane polymerization, introducing the surface-modified polymer hollow nanospheres into the polyurethane structure in the form of covalent bonds, thus endowing the polyurethane emulsion with flame retardant and heat insulation properties; in addition, chitosan contains abundant amino and hydroxyl groups, which enables the polyurethane to have good hydrophilic properties.
[0015] Preferably, in step four, the modified PA6 fiber is prepared by: Polyethylene glycol 2000 was melted in a water bath at 90°C, and then PA6 particles were added and stirred for 4-6 hours to obtain a mixture. The content of polyethylene glycol 2000 in the mixture was 20-30 wt%. The mixture was melt-spun at 235-285°C to obtain mixed fibers. The mixed fibers were immersed in distilled water and treated at 23-28°C for 2-4 hours. After being removed and dried to constant weight, modified PA6 fibers were obtained.
[0016] In the above process, polyethylene glycol 2000 is used as a pore-forming agent to be blended and spun with PA6 particles. Then, polyethylene glycol 2000 is washed away with distilled water to obtain modified PA6 fibers with a porous structure. The rich pore structure gives the fabric made of modified PA6 fibers excellent moisture absorption, breathability and heat preservation effects.
[0017] Preferably, the weight of the surface fabric is 100-120 g / m². 2 .
[0018] Preferably, in step four, the roll residue of the impregnation treatment is 50-80%.
[0019] Preferably, in step four, the baking conditions are: first pre-baking at 70-90℃ for 100-160s, and then baking at 140-160℃ for 100-160s.
[0020] Preferably, in step five, the filling amount of the filling fiber is 60-80 g / m³. 2 The filling fibers include polyester fibers.
[0021] The thermal insulation and breathable layered composite fabric is prepared using the aforementioned method.
[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The thermal insulation and breathable layered composite fabric of the present invention includes an inner layer fabric, a modified outer layer fabric, and polyester thermal insulation fibers filled between the two. The inner layer fabric is a functional cotton fabric. Cotton fabric has the advantages of strong moisture absorption, good breathability, softness and skin-friendliness, and good warmth retention. Functional cotton fabric is obtained by grafting cotton fabric. Because flame-retardant nitrogen, phosphorus and silicon elements are introduced into its surface and the pores are enlarged, it has better breathability and excellent flame-retardant performance. The modified surface fabric is obtained by treating the surface fabric with a polyurethane emulsion. The surface fabric is made of modified PA6 fiber. PA6 fiber has advantages such as high strength, wear resistance, and good moisture absorption. The modified PA6 fiber of this invention has a porous structure. The rich pore structure improves the moisture absorption, breathability, and heat insulation effect of the surface fabric. By treating the surface fabric with a polyurethane emulsion containing surface-modified polymer hollow nanospheres, the modified surface fabric is endowed with flame retardant and heat insulation properties. At the same time, because the chitosan on the surface of the surface-modified polymer hollow nanospheres contains abundant amino and hydroxyl groups, the polyurethane emulsion has good hydrophilic properties. Therefore, the surface fabric treated with polyurethane emulsion not only has improved moisture absorption and breathability, but also has excellent flame retardant and heat insulation properties. Furthermore, by filling the space between the inner and modified outer fabrics with polyester insulating fibers, an air gap is formed between the inner and modified outer fabrics, reducing air convection between the inner and outer layers of the fabric, thus improving the fabric's insulation performance. In summary, the thermal insulation and breathable layered composite fabric of the present invention, through the interaction of its various layers, simultaneously possesses both thermal insulation and breathability effects. Furthermore, it also exhibits excellent flame retardant properties, making it suitable for applications requiring flame retardant and fire-resistant performance, thereby further expanding the application scope of the thermal insulation and breathable layered composite fabric. Attached Figure Description
[0023] Figure 1 This is a comparison chart of the thermal insulation rate tests of the thermal insulation and breathable layered composite fabrics prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention. Figure 2 This is a comparison chart of the air permeability test results of the thermal insulation and breathable layered composite fabrics prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention. Figure 3 This is a comparison chart of the smoldering time and afterflame time of the heat-insulating and breathable layered composite fabrics prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention. Figure 4 This is a comparison chart of the damaged length test results of the thermal insulation and breathable layered composite fabrics prepared in Examples 1-3 and Comparative Examples 1-3 of the present invention. Detailed Implementation
[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0025] Example 1 This embodiment discloses a method for preparing a thermally insulating and breathable layered composite fabric, including the following steps: Step 1: Dissolve 4.6 mL of phosphorus oxychloride in 150 mL of tetrahydrofuran, cool to -70 °C, and stir under a nitrogen atmosphere. Then, add 150 mL of 1 mol / L vinyl magnesium bromide tetrahydrofuran solution at a rate of 2 mL / min. After the addition is complete, continue stirring at -68 °C for 3.5 h. Then, add 300 mL of 4 mol / L ammonium chloride aqueous solution to quench excess reactants. After the reaction system returns to room temperature, filter, separate the tetrahydrofuran layer, extract the aqueous layer twice with chloroform, combine the organic layers, dry with anhydrous sodium sulfate, filter, and remove chloroform by rotary evaporation to obtain trivinyl phosphorus-containing compound. Take twice the dry weight of deionized water from the cotton fabric, add diethylenetriaminepropyltrimethoxysilane to obtain a pretreatment solution; apply the pretreatment solution onto the cotton fabric, and then dry it at 60°C for 20 minutes to obtain the pretreated cotton fabric; wherein the coating content in the pretreated cotton fabric is 3.42 wt%. Take twice the dry weight of the pretreated cotton fabric in deionized water, add a trivinyl phosphorus compound to it to obtain a modification solution; apply the modification solution to the pretreated cotton fabric, dry it at 58°C for 20 min, then modify it under steam at 100°C for 20 min, and wash the modified cotton fabric four times with water at 38°C for 4 min each time to obtain a functionalized cotton fabric; wherein, the total coating content in the functionalized cotton fabric is 8 wt%; Step 2: Mix 21g of silica nanoparticles, 78.5g of toluene, 65.5g of triethylamine, and 2g of acetonitrile, and disperse by ultrasonication. Then add 0.9g of 1,3,5-triethynylbenzene, 0.05g of cuprous iodide, and 0.1g of tetrakis(triphenylphosphine)palladium, and disperse by ultrasonication. React at 76°C for 72h in a nitrogen atmosphere. Wash the reaction product sequentially with acetone, chloroform, deionized water, and methanol, and then dry to obtain a solid powder. Etch the solid powder in an etching solution with a solid-liquid mass ratio of 1:80, and let it stand for 5h. Wash the resulting product sequentially with acetone, chloroform, deionized water, and methanol, and then dry to obtain polymer hollow nanospheres. The etching solution is obtained by mixing HF, methanol, and deionized water in a volume ratio of 9:24:18. 1g of polymer hollow nanospheres were dispersed in 500g of deionized water and stirred. Acetic acid was added dropwise to adjust the pH of the solution to 6. Then 1.8g of chitosan was added. The mixture was centrifuged and the centrifuged product was vacuum dried at 65℃ and then ground to obtain surface-modified polymer hollow nanospheres. Step 3: In a nitrogen atmosphere, mix 5.55g of diphenylmethylene diisocyanate and 25g of polyethylene glycol 2000, stir for 20min, then add 0.02g of dibutyltin dilaurate, react at 78℃ for 6h, then add 0.9g of surface-modified polymer hollow nanospheres, react at 40℃ for 3h, then add 9g of 1,4-butanediol, stir vigorously for 5min, then add 100g of 1,3-dioxane to adjust the viscosity of the reaction system, continue stirring for 25min until the NCO content in the reaction system is less than 0.5%, evaporate the solvent, then add deionized water, emulsify, and obtain a polyurethane emulsion with a solid content of 20wt%. Step 4: Melt polyethylene glycol 2000 in a 90℃ water bath, then add PA6 granules and stir for 4 hours to obtain a mixture. The content of polyethylene glycol 2000 in the mixture is 20wt%. Melt-spin the mixture at 235℃ to obtain mixed fibers. Immerse the mixed fibers in distilled water at 23℃ for 4 hours, then remove and dry to constant weight to obtain modified PA6 fibers. Spin and knit the modified PA6 fibers to obtain a basis weight of 100g / m². 2 The surface fabric; A modified surface fabric is obtained by impregnating the surface fabric with a polyurethane emulsion, followed by baking and cooling; wherein the impregnation treatment has a roll-off rate of 50%, and the baking conditions are: pre-baking at 70°C for 160s, followed by baking at 140°C for 160s. Step 5: Using functionalized cotton fabric as the inner layer, lay filling fibers between the inner layer and the modified outer layer, and sew together to obtain a heat-insulating and breathable layered composite fabric; wherein the filling amount of the filling fibers is 60g / m². 2The filling fibers include polyester fibers.
[0026] Example 2 This embodiment discloses a method for preparing a thermally insulating and breathable layered composite fabric, including the following steps: Step 1: Dissolve 9.2 mL of phosphorus oxychloride in 300 mL of tetrahydrofuran, cool to -70 °C, and stir under a nitrogen atmosphere. Then, add 300 mL of 1 mol / L vinyl magnesium bromide tetrahydrofuran solution at a rate of 3 mL / min. After the addition is complete, continue stirring at -64 °C for 2.5 h. Then, add 500 mL of 4 mol / L ammonium chloride aqueous solution to quench excess reactants. After the reaction system returns to room temperature, filter, separate the tetrahydrofuran layer, extract the aqueous layer twice with chloroform, combine the organic layers, dry with anhydrous sodium sulfate, filter, and remove chloroform by rotary evaporation to obtain trivinyl phosphorus-containing compound. Take twice the dry weight of deionized water from the cotton fabric, add diethylenetriaminepropyltrimethoxysilane to obtain a pretreatment solution; apply the pretreatment solution onto the cotton fabric, and then dry it at 60°C for 40 minutes to obtain the pretreated cotton fabric; wherein the coating content in the pretreated cotton fabric is 6.84 wt%. Take twice the dry weight of the pretreated cotton fabric in deionized water, add a trivinyl phosphorus compound to it to obtain a modification solution; apply the modification solution to the pretreated cotton fabric, dry it at 62°C for 10 min, then modify it under steam at 100°C for 40 min, and wash the modified cotton fabric twice with water at 42°C, 4 min each time, to obtain a functionalized cotton fabric; wherein, the total coating content in the functionalized cotton fabric is 17 wt%; Step 2: Mix 42g of silica nanoparticles, 157g of toluene, 131g of triethylamine, and 4g of acetonitrile, and disperse by ultrasonication. Then add 1.8g of 1,3,5-triethynylbenzene, 0.1g of cuprous iodide, and 0.2g of tetrakis(triphenylphosphine)palladium, and disperse by ultrasonication. React at 80°C for 64h in a nitrogen atmosphere. Wash the reaction product sequentially with acetone, chloroform, deionized water, and methanol, and then dry to obtain a solid powder. Etch the solid powder in an etching solution with a solid-liquid mass ratio of 1:100, and let it stand for 5h. Wash the resulting product sequentially with acetone, chloroform, deionized water, and methanol, and then dry to obtain polymer hollow nanospheres. The etching solution is obtained by mixing HF, methanol, and deionized water in a volume ratio of 9:24:18. 1.5g of polymer hollow nanospheres were dispersed in 600g of deionized water and stirred. Acetic acid was added dropwise to adjust the pH of the solution to 6.4. Then 3.4g of chitosan was added. The mixture was centrifuged and the centrifuged product was vacuum dried at 65℃ and then ground to obtain surface-modified polymer hollow nanospheres. Step 3: In a nitrogen atmosphere, mix 11.1g of diphenylmethylene diisocyanate and 45g of polyethylene glycol 2000 and stir for 40min. Then add 0.06g of dibutyltin dilaurate and react at 82℃ for 4h. Then add 1.7g of surface-modified polymer hollow nanospheres and react at 50℃ for 2h. Then add 18g of 1,4-butanediol and stir vigorously for 4min. Then add 200g of 1,3-dioxane to adjust the viscosity of the reaction system and continue stirring for 15min until the NCO content in the reaction system is less than 0.5%. Evaporate the solvent, then add deionized water and emulsify to obtain a polyurethane emulsion with a solid content of 30wt%. Step 4: Melt polyethylene glycol 2000 in a 90°C water bath, then add PA6 granules and stir for 6 hours to obtain a mixture containing 30 wt% polyethylene glycol 2000. Melt-spin the mixture at 285°C to obtain mixed fibers. Immerse the mixed fibers in distilled water at 28°C for 2 hours, then remove and dry to constant weight to obtain modified PA6 fibers. Spin and knit the modified PA6 fibers to obtain a basis weight of 120 g / m². 2 The surface fabric; A modified surface fabric is obtained by impregnating the surface fabric with a polyurethane emulsion, followed by baking and cooling; wherein the padding rate of the impregnation treatment is 80%, and the baking conditions are: pre-baking at 90°C for 100s, followed by baking at 160°C for 100s. Step 5: Using functionalized cotton fabric as the inner layer, lay filling fibers between the inner layer and the modified outer layer, and sew together to obtain a heat-insulating and breathable layered composite fabric; wherein the filling amount of the filling fibers is 80g / m². 2 The filling fibers include polyester fibers.
[0027] Example 3 This embodiment discloses a method for preparing a thermally insulating and breathable layered composite fabric, including the following steps: Step 1: Dissolve 6.9 mL of phosphorus oxychloride in 225 mL of tetrahydrofuran, cool to -70 °C, and stir under a nitrogen atmosphere. Then, add 225 mL of 1 mol / L tetrahydrofuran solution of vinyl magnesium bromide at a rate of 2.5 mL / min. After the addition is complete, continue stirring at -66 °C for 3 h. Then, add 400 mL of 4 mol / L ammonium chloride aqueous solution to quench excess reactants. After the reaction system returns to room temperature, filter, separate the tetrahydrofuran layer, extract the aqueous layer twice with chloroform, combine the organic layers, dry with anhydrous sodium sulfate, filter, and remove chloroform by rotary evaporation to obtain trivinyl phosphorus-containing compound. Take twice the dry weight of the cotton fabric in deionized water, add diethylenetriaminepropyltrimethoxysilane to it to obtain a pretreatment solution; apply the pretreatment solution dropwise onto the cotton fabric, and then dry it at 60°C for 30 minutes to obtain the pretreated cotton fabric; wherein, the coating content in the pretreated cotton fabric is 5.13 wt%; Take twice the dry weight of the pretreated cotton fabric in deionized water, add a trivinyl phosphorus compound to it to obtain a modification solution; apply the modification solution to the pretreated cotton fabric, dry it at 60°C for 15 min, then modify it under steam at 100°C for 30 min, and wash the modified cotton fabric three times with water at 40°C for 3 min each time to obtain a functionalized cotton fabric; wherein, the total coating content in the functionalized cotton fabric is 12.5 wt%; Step 2: Mix 31.5g of silica nanoparticles, 117.75g of toluene, 98.3g of triethylamine, and 3g of acetonitrile, and disperse by ultrasonication. Then add 1.4g of 1,3,5-triethynylbenzene, 0.08g of cuprous iodide, and 0.2g of tetrakis(triphenylphosphine)palladium, and disperse by ultrasonication. React at 78°C for 68h in a nitrogen atmosphere. Wash the reaction product sequentially with acetone, chloroform, deionized water, and methanol, and then dry to obtain a solid powder. Etch the solid powder in an etching solution with a solid-liquid mass ratio of 1:90, and let it stand for 6h. Wash the resulting product sequentially with acetone, chloroform, deionized water, and methanol, and then dry to obtain polymer hollow nanospheres. The etching solution is obtained by mixing HF, methanol, and deionized water in a volume ratio of 9:24:18. 1.3g of polymer hollow nanospheres were dispersed in 550g of deionized water and stirred. Acetic acid was added dropwise to adjust the pH of the solution to 6.2. Then 2.6g of chitosan was added. After centrifugation, the centrifuged product was vacuum dried at 65℃ and then ground to obtain surface-modified polymer hollow nanospheres. Step 3: In a nitrogen atmosphere, 8.33g of diphenylmethylene diisocyanate was reacted at 80℃ for 5h, then 1.3g of surface-modified polymer hollow nanospheres were added, and the reaction was carried out at 45℃ for 2.5h. Then 13.5g of 1,4-butanediol was added, and the mixture was stirred vigorously for 5min. Then 150g of 1,3-dioxane was added to adjust the viscosity of the reaction system, and the mixture was stirred for another 20min until the NCO content in the reaction system was less than 0.5%. The solvent was evaporated, and then deionized water was added and emulsified to obtain a polyurethane emulsion with a solid content of 25wt%. Step 4: Melt polyethylene glycol 2000 in a 90°C water bath, then add PA6 granules and stir for 5 hours to obtain a mixture containing 25 wt% polyethylene glycol 2000. Melt-spin the mixture at 260°C to obtain mixed fibers. Immerse the mixed fibers in distilled water at 25°C for 3 hours, then remove and dry to constant weight to obtain modified PA6 fibers. Spin and knit the modified PA6 fibers to obtain a basis weight of 110 g / m². 2 The surface fabric; A modified surface fabric is obtained by impregnating the surface fabric with a polyurethane emulsion, followed by baking and cooling. The impregnation treatment has a roll-off rate of 65%, and the baking conditions are: pre-baking at 80°C for 130 seconds, followed by baking at 150°C for 130 seconds. Step 5: Using functionalized cotton fabric as the inner layer, lay filling fibers between the inner layer and the modified outer layer, and sew them together to obtain a heat-insulating and breathable layered composite fabric; wherein the filling amount of the filling fibers is 70g / m². 2 The filling fibers include polyester fibers.
[0028] Comparative Example 1 Compared with Example 3, in the process of preparing the thermal insulation and breathable layered composite fabric, Comparative Example 1 used cotton fabric instead of functional cotton fabric, while other conditions remained unchanged.
[0029] Comparative Example 2 Compared with Example 3, Comparative Example 2 used a surface layer fabric instead of a modified surface layer fabric in the process of preparing the thermal insulation and breathable layered composite fabric, while other conditions remained unchanged.
[0030] Comparative Example 3 Compared with Example 3, Comparative Example 3 used polyethylene glycol 2000 added during the preparation of modified PA6 fibers, while other conditions remained unchanged.
[0031] Experimental Example Performance tests were conducted on the thermal insulation and breathable layered composite fabrics prepared in Examples 1-3 and Comparative Examples 1-3: I. Thermal Insulation Performance Test: Referring to standard GB / T 11048-2018 "Determination of Thermal Resistance and Moisture Resistance of Textiles under Steady-State Conditions for Physiological Comfort (Evaporative Hot Plate Method)", a YG606E textile thermal resistance measuring instrument was used for testing. The sample size was 35cm×35cm, the experimental temperature was 35℃, and the wind speed was 1.0m / s. Three samples were cut from each type of fabric to test its thermal resistance and thermal insulation rate, and the average value of the results was taken. The thermal insulation rate corresponding to different fabrics was calculated according to formula (1): Equation (1); Where: Rct is the measured thermal resistance value (m)2 K) / W; Rct0 is the blank thermal resistance value (m) 2 K) / W.
[0032] II. Air permeability test: Waterproof performance was tested according to GB / T 4744-2013 standard; the test was conducted using a YG461G digital air permeability meter, with a test area of 20 cm², according to GB / T5453—1997 "Determination of Air Permeability of Textiles". 2 The test pressure was 100Pa, and each fabric was tested 10 times and the average value was taken. III. Flame retardant performance test: The test shall be conducted in accordance with the standard GB / T 5455-2014 "Determination of vertical damage length, smoldering and afterflame time in the burning performance test of textiles". The test results are shown in Table 1: Table 1
[0033] As can be seen from the test results in Table 1, the heat-insulating and breathable layered composite fabrics prepared in Examples 1-3 of the present invention have both heat-insulating and breathable effects, and also have excellent flame-retardant properties. As can be seen from the comparison between Comparative Example 1 and Example 3, the functionalized cotton fabric has introduced nitrogen, phosphorus and silicon flame retardant elements into its surface through chemical grafting, giving it excellent flame retardant properties. At the same time, compared with cotton fabric, the pore size of the functionalized cotton fabric surface is larger, thus it has better breathability. As can be seen from the comparison between Comparative Examples 2-3 and Example 3, the surface fabric in the embodiments of the present invention is made of modified PA6 fiber, which has a porous structure. The abundant pore structure improves the moisture absorption, breathability, and heat insulation effect of the surface fabric. By treating the surface fabric with a polyurethane emulsion containing surface-modified polymer hollow nanospheres, the modified surface fabric is endowed with flame retardant and heat insulation properties. At the same time, since the chitosan on the surface of the surface-modified polymer hollow nanospheres contains abundant amino and hydroxyl groups, the polyurethane emulsion has excellent hydrophilic properties. Therefore, the surface fabric treated with polyurethane emulsion modification not only has improved moisture absorption and breathability, but also has excellent flame retardant and heat insulation properties.
[0034] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a thermally insulating and breathable layered composite fabric, characterized in that, Includes the following steps: Step 1: Using phosphorus oxychloride and vinyl magnesium bromide as raw materials, prepare trivinyl phosphorus-containing compounds; then modify cotton fabrics with diethylenetriaminepropyltrimethoxysilane and trivinyl phosphorus-containing compounds to obtain functionalized cotton fabrics. Step 2: Using silica nanoparticles and 1,3,5-triethynyl-benzene as raw materials, polymer hollow nanospheres are prepared; chitosan is assembled on the surface of the polymer hollow nanospheres to obtain surface-modified polymer hollow nanospheres. Step 3: Prepare a polyurethane emulsion using diphenylmethylene diisocyanate, polyethylene glycol, and surface-modified polymer hollow nanospheres as the main raw materials; Step 4: Using polyethylene glycol as a pore-forming agent, mix it with PA6 particles, melt spin it, and prepare modified PA6 fibers; Modified PA6 fibers are spun and knitted to obtain the surface fabric; the surface fabric is then impregnated with polyurethane emulsion, baked, and cooled to obtain the modified surface fabric. Step 5: Use functionalized cotton fabric as the inner layer, lay filling fibers between the inner layer and the modified outer layer, and sew them together to obtain a heat-insulating and breathable layered composite fabric.
2. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step one, the method for preparing the functionalized cotton fabric is as follows: Take twice the dry weight of deionized water from the cotton fabric, add diethylenetriaminepropyltrimethoxysilane to obtain a pretreatment solution; apply the pretreatment solution onto the cotton fabric, and then dry it at 60°C for 20-40 minutes to obtain the pretreated cotton fabric; wherein the coating content in the pretreated cotton fabric is 3.42-6.84 wt%. Take twice the dry weight of the pretreated cotton fabric in deionized water, add a trivinyl phosphorus compound to it to obtain a modification treatment solution; apply the modification treatment solution to the pretreated cotton fabric, dry it at 58-62℃ for 10-20 min, then modify it under steam at 100℃ for 20-40 min, and wash the modified cotton fabric with water at 38-42℃ 2-4 times, each time for 2-4 min, to obtain a functionalized cotton fabric; wherein the total content of the coating in the functionalized cotton fabric is 8-17 wt%.
3. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step one, the preparation method of the trivinyl phosphorus-containing compound is as follows: Phosphorus oxychloride was dissolved in tetrahydrofuran, cooled to -70°C, and stirred under a nitrogen atmosphere. Then, a 1 mol / L tetrahydrofuran solution of vinyl magnesium bromide was added. After the addition was complete, the mixture was stirred at -68°C to -64°C for 2.5 to 3.5 hours. Then, 300 to 500 mL of a 4 mol / L ammonium chloride aqueous solution was added. After the reaction system returned to room temperature, the product was purified to obtain a trivinyl phosphorus-containing compound. The volume ratio of the phosphorus oxychloride solution, tetrahydrofuran, 1 mol / L tetrahydrofuran solution of vinyl magnesium bromide, and 4 mol / L ammonium chloride aqueous solution was (4.6 to 9.2):(150 to 300):(150 to 300):(300 to 500).
4. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step two, the preparation method of the polymer hollow nanospheres is as follows: Silica nanoparticles, toluene, triethylamine, and acetonitrile were mixed and sonicated. Then, 1,3,5-triethynylbenzene, cuprous iodide, and tetrakis(triphenylphosphine)palladium were added and sonicated. The mixture was then reacted at 76-80℃ for 64-72 h in a nitrogen atmosphere. The reaction product was washed and dried to obtain a solid powder. The solid powder was etched in an etching solution with a solid-liquid mass ratio of 1:(80-100), and allowed to stand for 5-7 hours to purify the product, thus obtaining polymer hollow nanospheres. The etching solution was obtained by mixing HF, methanol and deionized water in a volume ratio of 9:24:
18.
5. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 4, characterized in that, In the preparation of the solid powder, the mass ratio of silica nanoparticles, toluene, triethylamine, acetonitrile, 1,3,5-triethynylbenzene, cuprous iodide, and tetrakis(triphenylphosphine)palladium is (21-42):(78.5-157):(65.5-131):(2-4):(0.9-1.8):(0.05-0.1):(0.1-0.2).
6. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step two, the method for preparing the surface-modified polymer hollow nanospheres is as follows: Polymer hollow nanospheres were dispersed in deionized water and stirred. Acetic acid was added to adjust the pH of the solution to 6-6.
4. Chitosan was then added, and the product was purified to obtain surface-modified polymer hollow nanospheres. The mass ratio of the polymer hollow nanospheres, deionized water and chitosan was (1-1.5):(500-600):(1.8-3.4).
7. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step three, the preparation method of the polyurethane emulsion is as follows: In a nitrogen atmosphere, diphenylmethylene diisocyanate and polyethylene glycol 2000 are mixed and stirred for 20-40 min. Then, dibutyltin dilaurate is added, and the mixture is reacted at 78-82℃ for 4-6 h. Next, surface-modified polymer hollow nanospheres are added, and the mixture is reacted at 40-50℃ for 2-3 h. Then, 1,4-butanediol is added, and the mixture is stirred for 4-5 min. Finally, 1,3-dioxolane is added, and the mixture is stirred for another 15-25 min until the NCO content in the reaction system is less than 0.5%. The solvent is evaporated, and then deionized water is added and emulsified to obtain a polyurethane emulsion with a solid content of 20-30 wt%; wherein the mass ratio of diphenylmethylene diisocyanate, polyethylene glycol 2000, dibutyltin dilaurate, surface-modified polymer hollow nanospheres, 1,4-butanediol, and 1,3-dioxane is (5.55-11.1):(25-45):(0.02-0.06):(0.9-1.7):(9-18):(100-200).
8. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step four, the method for preparing the modified PA6 fiber is as follows: Polyethylene glycol 2000 was melted in a water bath at 90°C, and then PA6 particles were added and stirred for 4-6 hours to obtain a mixture. The content of polyethylene glycol 2000 in the mixture was 20-30 wt%. The mixture was melt-spun at 235-285°C to obtain mixed fibers. The mixed fibers were immersed in distilled water and treated at 23-28°C for 2-4 hours. After being removed and dried to constant weight, modified PA6 fibers were obtained.
9. The method for preparing the thermally insulating and breathable layered composite fabric according to claim 1, characterized in that, In step four, the roll residue of the dip-rolling treatment is 50-80%, and the baking conditions are: pre-baking at 70-90℃ for 100-160s, and then baking at 140-160℃ for 100-160s.
10. A thermally insulating and breathable layered composite fabric prepared by the method described in any one of claims 1-9.