Preparation process of functional warm-keeping fabric flocculus
Through electrospinning and nano-silver coating technology, fibers with a skin-core structure and aerogel nanopores are prepared, forming a fluffy and dispersed 3D network and surface groove structure, which solves the problem of heat loss in traditional thermal textiles and achieves efficient warmth retention and stability.
Patent Information
- Application Number
- CN202510869331.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-26
- Publication Date
- 2025-09-12
AI Technical Summary
Existing technologies have problems with inefficient energy utilization and difficulty in meeting human comfort in building heating and air-conditioning systems, and traditional thermal insulation textiles are difficult to effectively reduce heat loss.
Electrospinning technology is used to prepare fibers with a skin-core structure, combined with aerogel nanoporous structure and nanosilver coating to form multi-jet injection and double diffusion in a high humidity environment, forming a fluffy and dispersed 3D elastic network structure and a surface grooved pleated structure, enhancing still air accumulation and infrared radiation reflection.
Improves thermal insulation performance, reduces heat loss, and enhances fiber stability and thermal insulation effect.
Smart Images
Figure CN120625264A_ABST
Abstract
Description
Technical Field
[0001] The invention discloses a fabric technology, in particular to a preparation process of a functional warm-keeping fabric flake. Background Art
[0002] Clothing, as an essential element of human protection, meets basic thermal comfort needs by insulating against heat in extremely hot environments or providing warmth in freezing cold. Creating a comfortable environment through building heating, ventilation, and air-conditioning systems requires heating or cooling the entire building space, resulting in inefficient energy use and difficulty meeting human comfort requirements.
[0003] Animals rely primarily on fur to protect against the cold. Over time, the hair of some animals has evolved a remarkable multi-cavity structure. These cavities are filled with stagnant air, giving them low thermal conductivity and excellent insulating properties. Early humans used animal fur or cotton directly to create clothing to protect against the cold. Today, there is a great deal of interest in developing passive thermal insulation textiles. Thermal insulation textiles primarily achieve excellent thermal insulation through fiber morphology design, such as increasing the fabric's porosity and improving its bulk, which reduces air circulation and reduces heat conduction. Therefore, the development of functional thermal insulation textiles is of great significance. Summary of the Invention
[0004] The purpose of the present invention is to provide a preparation process of a functional warm-keeping fabric flake in order to solve the above problems.
[0005] To achieve the above-mentioned object, the present invention provides the following technical solution: a process for preparing a functional thermal insulation fabric flake, comprising the following steps:
[0006] S1, weighing TPU particles, dissolving them in DMF solvent, heating and stirring until dissolved, and then performing ultrasonic defoaming treatment to prepare a cortex spinning solution;
[0007] Weigh silica aerogel powder particles and dissolve them in another portion of DMF solvent, heat and stir until dissolved, and then perform ultrasonic defoaming treatment to obtain the skin layer spinning solution. Weigh TPU particles and add them, heat and stir until dissolved, and then perform ultrasonic defoaming treatment to obtain the core layer spinning solution.
[0008] S2, mixing the sheath spinning solution and the core spinning solution and placing them in a 25 wt % trimethyl carbinol aqueous solution for solvent exchange for 12 h to prepare a sheath-core spinning solution;
[0009] S4, adding polystyrene and polyurethane in a mass ratio of 3:2 into a mixed solution of acetone and dimethylacetamide, where the mass fraction of acetone is 0-30%, and stirring and dissolving to prepare a 20 wt% spinning solution;
[0010] S5, after adding 4wt% of trifunctional aziridine to the spinning solution, transfer it to one of the nozzles in the electrospinning machine injection device, and transfer the core-skin spinning solution to another nozzle in the electrospinning machine injection device. Control the two nozzles to evenly spray onto the receiving reel through electrospinning, and then transfer the flocculent material on the receiving reel to an oven and heat it under hot air at 80°C for 30 minutes to obtain functional warm fabric flocculent material.
[0011] Preferably, in S4, the mass fraction of acetone is 10%.
[0012] Preferably, in S5, the electrospinning temperature and relative humidity are set to 25° C. and 85%, respectively, and the electric field voltage is set to 35 kV.
[0013] Preferably, the functional thermal insulation fabric flakes are coated by a low-temperature magnetron sputtering method, comprising the following steps:
[0014] A1. Slowly open the exhaust valve of the magnetron sputtering chamber. After the exhaust is completed, close the exhaust valve tightly. Place the functional thermal insulation fabric flakes on the loading and unloading tray. After the functional thermal insulation fabric flakes enter the magnetron sputtering chamber, evacuate the chamber.
[0015] A2, under vacuum conditions, nano silver ions are sputtered onto functional thermal insulation fabric flakes through a magnetic field to form a coating with a coating thickness of 100nm.
[0016] Preferably, the mass ratio of the sheath spinning solution to the core spinning solution is 10:90.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] Under a high-voltage electric field, multiple Taylor cones are formed, allowing electrospinning to form multiple jets to prepare fibers with a skin-core structure and fibers with an aerogel nanoporous structure. Then, double diffusion is formed by the highly volatile solvent in the electrospinning jet and the water molecules in the high-humidity environment. Under the action of the high-voltage electric field, the stability of the charged jet is reduced, resulting in bending instability, inducing irregular phase separation of the jet and solidification to form a curled structure;
[0019] With the help of the phase separation of the skin spinning solution and the core spinning solution system during electrospinning, the TPU molecular chains are squeezed out by water molecules during solvent exchange and formed into a polymer skeleton with a large number of aerogel particles attached. The skin-core structure fiber formed by spinning the skin spinning solution and the core spinning solution has a significant radial pore structure in the skin layer, and the interior of the fiber is composed of micropores composed of a rich interconnected polymer network.
[0020] After the residual solvent is evaporated by heating the polymer skeleton and hot air, the fibers are partially shrunk and entangled, resulting in thermal melt solidification. This gives the fibers of the functional thermal insulation fabric flakes a surface grooved wrinkle structure, which in turn accumulates and stores more static air molecules. The rough grooved wrinkle structure inhibits the escape of air molecules to reduce heat loss, thereby improving thermal insulation performance. At the same time, the formation of long-chain structures and induced entanglement allow the fibers of the polystyrene and polyurethane jet-molded fibers to be interwoven with the fibers of the skin-core structure, ensuring the molding stability of the functional thermal insulation fabric flakes. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 The thermal conductivity of functional warm fabric flakes prepared with different mass ratios of skin spinning solution and core spinning solution;
[0022] Figure 2 The SEM image at 10 μm of the functional thermal insulation fabric flakes was prepared using a 10% by mass fraction of the cortical spinning solution;
[0023] Figure 3 The SEM image at 10 μm of the functional thermal insulation fabric flakes prepared with a cortical spinning solution with a mass fraction of 15%;
[0024] Figure 4 This is a SEM image of the fluffy and dispersed 3D elastic network structure of the functional thermal insulation fabric flakes;
[0025] Figure 5 This is a simplified structural diagram of the fluffy and dispersed 3D elastic network structure of the functional thermal insulation fabric wadding;
[0026] Figure 6 This is a microscopic SEM image of fibers in the functional thermal insulation fabric flakes;
[0027] Figure 7 This is a chart showing the thermal conductivity of functional thermal insulation fabric flakes at different magnetron coating thicknesses;
[0028] Figure 8 This is a chart showing the corresponding heat loss rates of functional thermal insulation fabric flakes at different magnetron coating thicknesses. DETAILED DESCRIPTION
[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0030] A preparation process of a functional thermal insulation fabric flake comprises the following steps:
[0031] S1, weighing TPU particles, dissolving them in DMF solvent, heating to 85°C and stirring for 4 hours to dissolve, and performing ultrasonic defoaming treatment under a vacuum of 0.04 MPa to prepare a cortex spinning solution;
[0032] Weigh silica aerogel powder particles and dissolve them in another portion of DMF solvent, heat to 50°C and stir for 3 hours to dissolve. After uniform dispersion, perform ultrasonic defoaming treatment to obtain the skin layer spinning solution. Weigh TPU particles and add them, heat and stir until dissolved, and then perform ultrasonic defoaming treatment to obtain the core layer spinning solution.
[0033] S2, mixing the sheath spinning solution and the core spinning solution and placing them in a 25 wt % trimethyl carbinol aqueous solution for solvent exchange for 12 h to prepare a sheath-core spinning solution;
[0034] The silica aerogel is wrapped in the TPU skin fiber using a skin-core structure. The solvent separation characteristics of the multi-jet electrospinning process are used to replace the original porous structure of the fiber formed by the protective skin-core structure with tert-butyl alcohol, achieving a continuous network structure after the final composite.
[0035] like Figure 1The figure shows the thermal conductivity of functional thermal insulation fabric flakes prepared with different mass ratios of skin spinning solution and core spinning solution (①5:98; ②7.5:92.5; ③10:90; ④15:85). The thermal conductivity test method is the transient hot wire method. A thin metal wire is placed in the functional thermal insulation fabric flake sample to be tested as a hot wire source. Under the condition of constant heating power, if the thermal conductivity of the tested sample is high, the generated heat will be transferred out quickly, and the hot wire temperature rise will be small. On the contrary, if the thermal conductivity of the material is low, the generated heat will be dissipated slowly, and the hot wire temperature rise will be large. From ①-③, it can be seen that as the proportion of skin spinning solution increases, the thermal conductivity shows a downward trend, reaching the lowest at a mass fraction of 10%. However, when the proportion of skin spinning solution increases to 15%, it shows an increasing trend instead.
[0036] Cause analysis such as Figure 2 and Figure 3 Shown are SEM images of functional thermal insulation fabric flakes at 10 μm when the mass fraction is 10% and 15%, respectively. It can be observed that when the mass fraction is 10%, due to the phase separation of the skin spinning solution and the core spinning solution system during electrospinning, the TPU molecular chains are squeezed out and formed by water molecules during solvent exchange to form a polymer skeleton, and a large number of aerogel particles are attached. The skin-core structure fiber formed by spinning the skin spinning solution and the core spinning solution has a significant radial pore structure, and the interior of the fiber is composed of micropores composed of a rich interconnected polymer network. However, when the proportion of the skin spinning solution continues to increase, the defects of the core layer of the skin-core structure fiber formed by spinning the skin spinning solution and the core spinning solution increase, and the TPU molecular chains aggregate, and the attached aerogel particles decrease, resulting in a decrease in thermal conductivity. In summary, the mass ratio of the skin spinning solution to the core spinning solution is selected as 10:90 as the preparation ratio.
[0037] S4, adding polystyrene and polyurethane in a mass ratio of 3:2 into a mixed solution of acetone and dimethylacetamide, where the mass fraction of acetone is 0-30%, and stirring and dissolving to prepare a 20 wt% spinning solution;
[0038] S5, adding 4 wt% of trifunctional aziridine to the spinning solution and transferring it to one of the jet heads in the electrospinning machine's jet device. The core-spinning solution is then transferred to another jet head in the electrospinning machine's jet device. The two jet heads are controlled to uniformly spray the solution onto a receiving reel through electrospinning. The flocculent material on the receiving reel is then transferred to an oven and heated at 80°C in hot air for 30 minutes to obtain a functional thermal insulation fabric flocculent material.
[0039] In S5, the electrospinning set temperature and relative humidity were 25°C and 85%, respectively, and the electric field voltage was set to 35kV. By adjusting the set temperature and electric field voltage, the solvent volatilization rate and the charge density and phase separation phenomenon of the charged jet during electrospinning can be controlled. When the relative humidity is increased to 85%, the charged jet exchanges charges with the water molecules in the environment, improving the charge movement. Moreover, the charge density increases under high electric field voltage, and the electric field is gradually transferred to the edge of the nozzle, thereby forming multiple Taylor cones, and then obtaining multi-jet injection, so that the highly volatile solvent in the electrospinning jet and the water molecules in the high humidity environment form double diffusion. Under the action of the high voltage electric field, the stability of the charged jet is reduced, resulting in bending instability, inducing irregular phase separation of the jet to form a curled structure after solidification;
[0040] During the jetting process, polystyrene, polyurethane and trifunctional aziridine form a large amount of polymer-rich phase and non-solvent-rich phase on the surface and inside the jet. The polymer-rich phase solidifies to form fibers, and the rapid evaporation of the non-solvent forms an aerogel nanoporous structure on the surface and inside the single fiber, while the remaining molecular chains are interlocked and cross-linked to form an entanglement, forming a Figure 4 and Figure 5 The fluffy and dispersed 3D elastic network structure shown in the figure is formed by the rapid solidification of the spinning solution jet due to the high humidity, so that part of the solvent in the spinning solution is not completely volatilized and remains between the fibers of the functional thermal insulation fabric flakes after forming;
[0041] In S4, when the mass fraction of acetone is too low and lower than 10%, the solvent in the spinning solution jet is completely volatilized, and it is difficult for the fibers in the functional thermal insulation fabric flakes to form an entangled and bonded state, and the fibers are relatively dispersed. However, when the mass fraction of acetone is too high and higher than 15%, a large amount of solvent is retained in the spinning solution, which makes the fiber forming discontinuous and produces a large number of defects and breakages. In summary, after the acetone mass fraction is 10% for preparation, part of the solvent is retained and not completely volatilized. After the residual solvent is evaporated by heating at 80℃ hot air, it is heated for micro-dehydration to form partial shrinkage and entanglement between the fibers, and the fibers are hot-melt solidified. The microstructure is as follows Figure 6 As shown, the surface presents a grooved pleated structure, which accumulates and stores more static air molecules. The rough grooved pleated surface inhibits the escape of air molecules to reduce heat loss, thereby improving thermal insulation performance. At the same time, the formation of long chain structures and induced entanglement allow the fibers of polystyrene and polyurethane injection molding to be interwoven with the fibers of the skin-core structure, ensuring the molding stability of the functional thermal insulation fabric flakes.
[0042] The functional thermal insulation fabric flakes are coated by a low-temperature magnetron sputtering method, which includes the following steps:
[0043] A1. Slowly open the exhaust valve of the magnetron sputtering chamber. After the exhaust is completed, close the exhaust valve tightly. Place the functional thermal insulation fabric flakes on the loading and unloading tray. After the functional thermal insulation fabric flakes enter the magnetron sputtering chamber, evacuate the chamber.
[0044] A2, under vacuum conditions, nano silver ions are sputtered onto functional thermal insulation fabric flakes through a magnetic field to form a coating with a thickness of 100 nm;
[0045] The silver target material adopts the specifications of 3.2Ra finish and 99.99% purity. Magnetron sputtering is a high-speed sputtering under low pressure, which effectively improves the ionization rate of the gas. Magnetron sputtering introduces a magnetic field on the surface of the target cathode, and uses the magnetic field to confine the charged particles to increase the plasma density and increase the sputtering rate. A low-temperature magnetron sputtering method is used, with the silver target material at the bottom and the functional thermal insulation fabric flakes at the top, to deposit a nanosilver film on the surface of the functional thermal insulation fabric flakes. The magnetron sputtering time is designed according to the set thickness of the coating. Four groups of different coating thicknesses are designed to compare the thermal conductivity and heat radiation loss rate between the functional thermal insulation fabric flakes. The thermal conductivity is still tested using the transient hot wire method, and the thermal reflectivity is measured using a mid-infrared diffuse reflectance integrating sphere combined with a Fourier transform infrared spectrometer. After heating the functional thermal insulation fabric flakes with a hot wire, the changes in the infrared diffuse reflectance integrating sphere located on the outside of the functional thermal insulation fabric flakes are measured using a Fourier transform infrared spectrometer, such as Figure 7 As shown in Figure 2, as the coating thickness increases, the thermal conductivity of the functional thermal insulation fabric flakes gradually increases, which is 3%-12% higher than that without coating. Figure 8 As shown in the figure, as the coating thickness increases, the average heat radiation loss rate of the functional thermal insulation fabric flakes in the range of 7-14μm is 32%-46%. The reason for this is that a denser silver nanoparticle layer will be formed on the surface of the fabric, thereby enhancing the reflection of infrared radiation, and strongly inhibiting the heat loss of the outer surface, reducing the radiation heat loss, and achieving the effect of keeping warm. When the coating thickness is 100nm, the thermal conductivity increases by 3%, and the average heat radiation loss rate is 35%. When the coating thickness is 200nm, the thermal conductivity increases by 12%, and the average heat radiation loss rate is 31%. In summary, the overall heat loss rate of the coating with a coating thickness of 100nm is the lowest, and the thermal insulation performance is better.
[0046] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.
[0047] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.
Claims
1. A process for preparing a functional warm-keeping fabric flake, characterized in that: The following steps are involved: S1, weighing TPU particles, dissolving them in DMF solvent, heating and stirring until dissolved, and then performing ultrasonic defoaming treatment to prepare a cortex spinning solution; Weigh silica aerogel powder particles and dissolve them in another portion of DMF solvent, heat and stir until dissolved, and then perform ultrasonic defoaming treatment to obtain the skin layer spinning solution. Weigh TPU particles and add them, heat and stir until dissolved, and then perform ultrasonic defoaming treatment to obtain the core layer spinning solution. S2, mixing the sheath spinning solution and the core spinning solution and placing them in a 25 wt % trimethyl carbinol aqueous solution for solvent exchange for 12 h to prepare a sheath-core spinning solution; S4, adding polystyrene and polyurethane in a mass ratio of 3:2 into a mixed solution of acetone and dimethylacetamide, where the mass fraction of acetone is 0-30%, and stirring and dissolving to prepare a 20 wt% spinning solution; S5, after adding 4wt% of trifunctional aziridine to the spinning solution, transfer it to one of the nozzles in the electrospinning machine injection device, and transfer the core-skin spinning solution to another nozzle in the electrospinning machine injection device. Control the two nozzles to evenly spray onto the receiving reel through electrospinning, and then transfer the flocculent material on the receiving reel to an oven and heat it under hot air at 80°C for 30 minutes to obtain functional warm fabric flocculent material.
2. The process for preparing a functional warm-keeping fabric flake according to claim 1, characterized in that: In S4, the mass fraction of acetone was 10%.
3. The process for preparing a functional warm-keeping fabric flake according to claim 1, characterized in that: In S5, the electrospinning temperature and relative humidity were set at 25 °C and 85%, respectively, and the electric field voltage was set at 35 kV.
4. The process for preparing a functional warm-keeping fabric flake according to claim 1, characterized in that: The functional thermal insulation fabric flakes are coated by a low-temperature magnetron sputtering method, which includes the following steps: A1. Slowly open the exhaust valve of the magnetron sputtering chamber. After the exhaust is completed, close the exhaust valve tightly. Place the functional thermal insulation fabric flakes on the loading and unloading tray. After the functional thermal insulation fabric flakes enter the magnetron sputtering chamber, evacuate the chamber. A2, under vacuum conditions, nano silver ions are sputtered onto functional thermal insulation fabric flakes through a magnetic field to form a coating with a coating thickness of 100nm.
5. The process for preparing a functional warm-keeping fabric flake according to claim 1, characterized in that: The mass ratio of the skin layer spinning solution to the core layer spinning solution is 10:90.