Lightweight thermal facing material and method of making same

Abstract

The application discloses a kind of light thermal insulation fabric and preparation method thereof, belong to textile field.The fabric is interwoven by polyester fiber and aramid fiber with mass ratio 70 to 30, polyester fiber diameter is 12 to 16 microns, aramid fiber diameter is 10 to 14 microns, fabric density is 180 to 220 per 10 centimeters.Preparation method includes low temperature plasma treatment fabric matrix, preparation composite coating consisting of amino silane coupling agent modified nanoporous silicate particles and crosslinking type two-component waterborne polyurethane, after uniform dispersion of nanoparticle using ultrasonic assisted dispersion technology, fabric is immersed, finally heat curing under the condition of relative humidity 40 to 60 percent, temperature 80 to 120 degrees Celsius, form coating with thickness 5 to 15 microns, porosity 40 to 60 percent.The beneficial effect: the fabric of the application is combined closely, structure is uniform, has good lightness and thermal insulation performance.

Description

Technical Field

[0001] The present invention relates to the field of textiles, and more particularly to a lightweight thermal insulation fabric and a preparation method thereof. Background Art

[0002] As an important branch of functional textile materials, lightweight thermal insulation fabrics have achieved remarkable development in recent years with the advancement of materials science and textile technology. Traditional thermal insulation fabrics mainly rely on thick natural or synthetic fibers. Although they have certain thermal insulation properties, they generally have problems such as heavy weight, poor breathability and insufficient comfort. With the application of nanotechnology and composite materials, researchers have begun to use nanoparticle-reinforced coatings and high-performance fiber composites to improve the thermal insulation effect and lightweight performance of fabrics. In addition, the design of fabric structures is constantly being optimized, and the mechanical strength and flexibility of fabrics are enhanced by adjusting the fiber ratio, fabric density and fabric twist. Surface treatment technologies, such as plasma treatment, have also been introduced to improve coating adhesion and enhance product durability.

[0003] Despite this, the existing technology still has several shortcomings. On the one hand, the dispersion of nanoparticles in the coating is uneven, resulting in fluctuations in coating performance and local weakness. On the other hand, the bonding strength between the coating and the fabric substrate is limited, and peeling and cracking are prone to occur, affecting long-term performance. In addition, the control of key parameters such as impregnation time, curing environment humidity and temperature in the preparation process is not precise enough, making it difficult to ensure product consistency. Although the fabric structure design has been improved, parameters such as fiber combination ratio and fabric density have not yet reached the optimal level, which limits the simultaneous improvement of lightweight and thermal insulation performance. Based on the above shortcomings, there is an urgent need to develop a lightweight thermal insulation fabric and a preparation method thereof that takes into account fabric structure optimization, efficient dispersion of nanoparticles and interface bonding reinforcement to meet application requirements of higher performance and stability. Summary of the Invention

[0004] The purpose of the present invention is to provide a lightweight thermal insulation fabric and a preparation method thereof, so as to solve the problems raised in the above-mentioned background technology: on the one hand, the dispersion of nanoparticles in the coating is uneven, resulting in fluctuations in coating performance and local weakness. On the other hand, the bonding strength between the coating and the fabric substrate is limited, and peeling and cracking are prone to occur, affecting long-term performance. In addition, the control of key parameters such as immersion time, curing environment humidity and temperature in the preparation process is not precise enough, resulting in difficulty in ensuring product consistency. Although the fabric structure design has been improved, parameters such as fiber combination ratio and fabric density have not yet reached the optimal level, which limits the simultaneous improvement of lightweight and thermal insulation performance.

[0005] Technical solution: A lightweight thermal insulation fabric, comprising a polyester fiber and aramid fiber fabric matrix interwoven in a mass ratio of 70:30, wherein the fiber diameter of the polyester fiber is 12 to 16 microns, the fiber diameter of the aramid fiber is 10 to 14 microns, and the fabric density is 180 to 220 fibers per 10 cm.

[0006] Preferably, the twist of the fiber bundles of the fabric matrix is ​​250 to 350 turns per meter, and the fabric thickness is 0.25 to 0.35 mm.

[0007] Preferably, the surface of the fabric substrate is coated with a composite coating, which is composed of nanoporous silicate particles chemically modified with an aminosilane coupling agent and a cross-linked two-component water-based polyurethane resin, and the particle size of the nanoporous silicate particles is 50 to 200 nanometers; the thickness of the composite coating is 5 to 15 microns.

[0008] Preferably, the mass fraction of the nanoporous silicate particles in the composite coating is 30 to 50 percent, and the porosity is 40 to 60 percent.

[0009] Preferably, the nanoporous silicate particles are prepared by a sol-gel method, the pH value of the sol is controlled in the range of 3 to 5, and the surface of the particles is modified with 3-aminopropyltriethoxysilane.

[0010] Preferably, the method for preparing a lightweight thermal insulation fabric comprises the following steps:

[0011] S1. The polyester fiber and the aramid fiber are opened and carded in a mass ratio of 70 to 30, and interwoven on a twill loom to form a fabric matrix. The fabric density is controlled at 180 to 220 strands per 10 cm, the fiber bundle twist is controlled at 250 to 350 turns per meter, and the fabric thickness is controlled at 0.25 to 0.35 mm.

[0012] S2 the fabric substrate is subjected to low-temperature plasma treatment, the gas used is a mixture of oxygen and nitrogen, the processing power is 100 to 200 watts, the processing time is 5 to 15 minutes;

[0013] S3. Prepare a composite coating solution comprising nanoporous silicate particles modified with an aminosilane coupling agent and a cross-linked two-component aqueous polyurethane resin, wherein the nanoporous silicate particles have a particle size of 50 to 200 nm and the particle content accounts for 30 to 50 percent by mass of the combined coating solution;

[0014] S4. Ultrasonic-assisted dispersion technology is used at an ultrasonic frequency of 20 to 40 kHz for 15 to 25 minutes to uniformly disperse the nanoporous silicate particles in the polyurethane solution;

[0015] S5. The plasma-treated fabric substrate is immersed in the composite coating solution for a period of 5 to 10 minutes;

[0016] S6. Thermally cure the coating at 80 to 120 degrees Celsius for 15 to 30 minutes under a relative humidity of 40 to 60 percent to form a composite coating having a thickness of 5 to 15 microns and a porosity of 40 to 60 percent.

[0017] Preferably, the nanoporous silicate particles are prepared by controlling the pH value in the sol-gel process within the range of 3 to 5, controlling the gelation time within 12 to 24 hours, and performing a 3-aminopropyltriethoxysilane surface modification treatment after particle formation for 1 to 3 hours.

[0018] Preferably, the cross-linked two-component waterborne polyurethane resin is prepared by mixing an isocyanate component and a polyether polyol component in a weight ratio of 1 to 1.1, and the mixing shear rate is controlled at 500 to 700 per second.

[0019] Preferably, the distance between the fabric substrate and the heating source during the thermal curing process is 10 to 15 cm, there is no crack on the coating surface after curing, and the bonding strength between the coating and the fabric substrate is greater than 3 MPa.

[0020] Compared with the prior art, the advantages of the present invention are:

[0021] (1) The fabric matrix is ​​made of polyester fiber and aramid fiber precisely interwoven at a mass ratio of 70:30, optimizing the fiber diameter, fabric density and fiber bundle twist parameters to improve lightness and structural stability.

[0022] (2) Use low-temperature plasma to treat the fabric substrate, and use oxygen and nitrogen mixed gas to enhance the surface activity of the fabric and the adhesion of the coating, thereby improving the bonding performance between the coating and the substrate.

[0023] (3) Nanoporous silicate particles chemically modified with aminosilane coupling agents are introduced into the coating, and the particle size is strictly controlled between 50 and 200 nanometers, which significantly improves the coating uniformity and interface bonding strength.

[0024] (4) A cross-linked two-component waterborne polyurethane resin and nanoparticle composite coating is used, and the uniform distribution of nanoparticles is achieved through ultrasound-assisted dispersion technology, thereby improving the microporous structure and thermal insulation performance of the coating.

[0025] (5) During the preparation process, the porosity of the composite coating is controlled to be between 40 and 60 percent, and a controlled humidity environment heat curing process is used to effectively optimize the coating structure, improve the thermal insulation effect and coating stability.

[0026] (6) Nanoporous silicate particles are prepared by regulating the pH value and gel time of the sol-gel process and performing chemical surface modification to enhance the dispersibility of the particles and their chemical bonding with the polyurethane matrix.

[0027] (7) The process parameters in the preparation method are strictly limited, including ultrasonic frequency, immersion time, thermal curing temperature and time, to ensure the stability of the preparation process and the consistency of product performance.

[0028] (8) Control the distance between the fabric substrate and the heating source during the thermal curing process to ensure that the coating is crack-free and the bonding strength is greater than 3 MPa, thereby improving the mechanical durability of the fabric. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the overall process of a method for preparing a lightweight thermal insulation fabric according to the present invention; DETAILED DESCRIPTION

[0030] Example

[0031] Examples 1-4

[0032] Example 1. A lightweight thermal insulation fabric comprises a polyester fiber and aramid fiber fabric matrix interwoven in a mass ratio of 70:30, the fiber diameter of the polyester fiber is 12 to 16 microns, the fiber diameter of the aramid fiber is 10 to 14 microns, and the fabric density is 180 to 220 fibers per 10 cm.

[0033] The fiber bundles of the fabric matrix have a twist of 250 to 350 turns per meter and the fabric thickness is 0.25 to 0.35 mm.

[0034] The surface of the fabric substrate is coated with a composite coating, which is composed of nanoporous silicate particles chemically modified with an aminosilane coupling agent and a cross-linked two-component water-based polyurethane resin. The particle size of the nanoporous silicate particles is 50 to 200 nanometers; the thickness of the composite coating is 5 to 15 microns.

[0035] The mass fraction of the nanoporous silicate particles in the composite coating is 30 to 50 percent, and the porosity is 40 to 60 percent.

[0036] The nanoporous silicate particles are prepared by a sol-gel method, the pH value of the sol is controlled in the range of 3 to 5, and the surface of the particles is modified by using 3-aminopropyltriethoxysilane.

[0037] A method for preparing a lightweight thermal insulation fabric comprises the following steps:

[0038] S1. The polyester fiber and the aramid fiber are opened and carded in a mass ratio of 70 to 30, and interwoven on a twill loom to form a fabric matrix. The fabric density is controlled at 180 to 220 strands per 10 cm, the fiber bundle twist is controlled at 250 to 350 turns per meter, and the fabric thickness is controlled at 0.25 to 0.35 mm.

[0039] S2 the fabric substrate is subjected to low-temperature plasma treatment, the gas used is a mixture of oxygen and nitrogen, the processing power is 100 to 200 watts, the processing time is 5 to 15 minutes;

[0040] S3. Prepare a composite coating solution comprising nanoporous silicate particles modified with an aminosilane coupling agent and a cross-linked two-component aqueous polyurethane resin, the nanoporous silicate particles having a particle size of 50 to 200 nm, and the particle content accounting for 30 to 50 percent by mass of the combined coating solution;

[0041] S4. Ultrasonic dispersion technology is used at an ultrasonic frequency of 20 to 40 kHz for 15 to 25 minutes to uniformly disperse the nanoporous silicate particles in the polyurethane solution;

[0042] S5. The plasma-treated fabric substrate is immersed in the composite coating solution for a period of 5 to 10 minutes;

[0043] S6. Thermally cure the coating at 80 to 120 degrees Celsius for 15 to 30 minutes under a relative humidity of 40 to 60 percent to form a composite coating having a thickness of 5 to 15 microns and a porosity of 40 to 60 percent.

[0044] The nanoporous silicate particles are prepared by controlling the pH value in the range of 3 to 5 in the sol-gel process, controlling the gelation time in the range of 12 to 24 hours, and performing a 3-aminopropyltriethoxysilane surface modification treatment after the particles are formed, with the treatment time being 1 to 3 hours.

[0045] The cross-linked two-component waterborne polyurethane resin is prepared by mixing an isocyanate component and a polyether polyol component in a weight ratio of 1 to 1.1, and the mixing shear rate is controlled at 500 to 700 per second.

[0046] During the thermal curing process, the distance between the fabric substrate and the heating source is 10 to 15 cm. After curing, there is no crack on the coating surface, and the bonding strength between the coating and the fabric substrate is greater than 3 MPa.

[0047] Example 2. The difference from Example 1 is that the polyester fiber has a diameter of 14 microns and the aramid fiber has a diameter of 12 microns; the fabric density is 200 strands per 10 cm; the fiber bundle twist is 300 turns per meter; and the fabric thickness is 0.30 mm.

[0048] The nanoporous silicate particles have a particle size of 100 nanometers and are modified with 3-aminopropyltriethoxysilane. The particle content is 40% of the composite coating mass. The composite coating is 10 microns thick and has a porosity of 50%.

[0049] Low-temperature plasma treatment uses an oxygen-nitrogen mixed gas with a power of 150 watts and a treatment time of 10 minutes.

[0050] Ultrasonic assisted dispersion frequency was 30 kHz and duration was 20 min.

[0051] Thermal curing temperature is 110 degrees Celsius, time is 20 minutes, relative humidity is 50%.

[0052] Example 3. The difference from Example 1 is that the fabric density is adjusted to 185 fibers per 10 cm, the fiber bundle twist is 270 turns per meter, and the fabric thickness is 0.28 mm.

[0053] The nanoparticle size is 150 nanometers, the particle content is 45%, the coating thickness is 12 microns, and the porosity is 55%.

[0054] The low-temperature plasma power is 120 watts and the processing time is 7 minutes.

[0055] The ultrasonic frequency was 25 kHz and the duration was 18 minutes.

[0056] Thermal curing temperature is 100 degrees Celsius, time is 25 minutes, relative humidity is 45%.

[0057] Example 4. The difference from Example 1 is that the polyester fiber has a diameter of 12 microns and the aramid fiber has a diameter of 14 microns; the fabric density is 210 fibers per 10 cm, the fiber bundle twist is 320 turns per meter, and the fabric thickness is 0.33 mm.

[0058] The nanoparticle size is 80 nanometers, the particle content is 35%, the coating thickness is 8 microns, and the porosity is 42%.

[0059] The plasma power was 180 W and the treatment time was 12 minutes.

[0060] The ultrasonic frequency was 35 kHz and the duration was 22 minutes.

[0061] Thermal curing temperature is 115 degrees Celsius, time is 18 minutes, relative humidity is 55%.

[0062] Comparative Example

[0063] Comparative Examples 1-3

[0064] Comparative Example 1. Unlike Example 1, the fabric substrate was not subjected to low-temperature plasma treatment, resulting in decreased adhesion of the coating and easy peeling.

[0065] The nanoparticles were not modified with aminosilane coupling agent, the coating had poor dispersion and obvious particle agglomeration.

[0066] When the ultrasonic dispersion time was shortened to 5 minutes, the particle distribution was uneven.

[0067] The thermal curing temperature is 90 degrees Celsius, the time is 10 minutes, and the coating porosity is less than 30%.

[0068] Comparative Example 2: Using non-cross-linked one-component polyurethane resin instead of cross-linked two-component waterborne polyurethane resulted in poor coating stability and decreased mechanical properties.

[0069] The nanoparticle size range is over 250 nanometers, the particle size distribution is wide, and the coating surface is rough.

[0070] The fabric density is only 150 fibers per 10 cm, the twist of the fiber bundle is less than 200 turns per meter, the fabric structure is loose, and the thermal insulation effect is poor.

[0071] Comparative Example 3: The ultrasonic-assisted dispersion process was omitted and mechanical stirring was used, resulting in poor dispersion and aggregation of the nanoparticles.

[0072] The low-temperature plasma treatment time is only 2 minutes, the power is 50 watts, and the surface modification effect is limited.

[0073] The thermal curing process is carried out in an uncontrolled humidity environment, and the coating has an uneven pore structure with a porosity of less than 35%.

[0074] In order to determine the dispersion uniformity of the nanoparticles and the adhesion of the coatings in the examples and comparative examples, the following comparative experiments were designed. The experimental steps are as follows:

[0075] Experimental article preparation: lightweight thermal insulation fabric samples, including one each of the fabrics prepared in Example 2, Example 3, and Comparative Example 1 and Comparative Example 3, all with a size of 10 cm × 10 cm.

[0076] Ultrasonic cleaning machine (frequency adjustable 20-40 kHz).

[0077] Coating adhesion testing equipment (pull-off tape tester).

[0078] Optical microscopy and scanning electron microscopy (SEM) were used to observe the dispersion state of the coating nanoparticles.

[0079] Standard adhesive tape for adhesion testing.

[0080] Constant temperature and humidity chamber, used to simulate coating curing conditions.

[0081] Common laboratory instruments such as precision balances and graduated cylinders.

[0082] The specific experimental steps are as follows:

[0083] To observe nanoparticle dispersion, we examined the surface distribution of nanoparticles on the coating of each sample using an optical microscope at 500x magnification, noting any agglomeration and uniformity. High-resolution SEM images were then taken of representative areas to further examine the dispersion of the nanoparticles.

[0084] For the coating adhesion test, firmly apply a standard tape to the sample coating surface, press firmly for 5 seconds, and then quickly peel it off. Repeat this process five times. Calculate the percentage of coating peeled off after each peel to assess the bonding strength between the coating and the fabric substrate.

[0085] For the peeling resistance test, samples were placed in a constant temperature and humidity chamber set at 40°C and 80% relative humidity for 72 hours. After aging, the coating adhesion test was repeated to assess changes in the coating's resistance to environmental erosion.

[0086] For data recording and statistical analysis, three parallel experiments were conducted for each test, and the average value was taken and the statistical error was calculated.

[0087] The experimental data are shown in the following table:

[0088]

[0089] Analysis of experimental conclusions: The nanoparticle dispersion uniformity of Examples 2 and 3 is significantly better than that of Comparative Examples 1 and 3, and the particle agglomeration area is smaller, indicating that the ultrasonic-assisted dispersion and nanoparticle surface modification technology of the present invention effectively improves the uniformity of particle distribution. The coating adhesion test results show that the embodiment coating is more tightly bonded to the fabric substrate and has a lower peeling area, indicating that the plasma treatment and composite coating technology enhance the interface bonding performance. After the aging test, the coating adhesion of the embodiment sample decreased less, showing better environmental stability and durability. The comparative example sample showed a significant increase in peeling and particle agglomeration, reflecting the insufficient performance caused by the failure to adopt the key process of the present invention. In summary, the present invention effectively solves the problems of insufficient nanoparticle dispersion and coating bonding in the prior art through a number of innovative technologies, and significantly improves the overall performance of lightweight thermal insulation fabrics.

[0090] In order to determine the surface hydrophilicity of the fabrics of the embodiment and the comparative example and the performance of the porous structure of the composite coating, the following comparative experiment was designed. The experimental steps are as follows:

[0091] Experimental article preparation: lightweight thermal insulation fabric samples, including one each of Example 4, Example 2, Comparative Example 2, and Comparative Example 3, all with a size of 10 cm × 10 cm.

[0092] Contact angle meter, used to measure the contact angle of static water droplets on fabric surfaces.

[0093] Gas adsorption instrument, used to determine the porous structure parameters of the coating (specific surface area and pore volume).

[0094] Ultrasonic cleaning machine and precision balance.

[0095] Standard burette and pure water.

[0096] The temperature of the thermostat is controlled at 25 degrees Celsius.

[0097] The specific experimental steps are as follows:

[0098] Fabric surface hydrophilicity test: Use a standard burette to add 5 μl of pure water to the fabric surface. Use a contact angle meter to record the static water drop contact angle. Measure at four different locations on the sample and take the average value as the fabric hydrophilicity index.

[0099] Coating porous structure test: Take a coating film sample and use a gas adsorption instrument to measure the specific surface area and pore volume. Based on the nitrogen adsorption isotherm data, calculate the coating porosity and pore size distribution.

[0100] Hydrophilicity stability test: Place the sample in a constant temperature chamber at 25 degrees Celsius and 60% humidity for 72 hours, then repeat the hydrophilicity test to detect changes in hydrophilicity.

[0101] Data statistics and analysis: Each test was repeated three times, and the mean and standard deviation were calculated.

[0102] The experimental data are shown in the following table:

[0103]

[0104] Analysis of experimental conclusions: The fabric surfaces of Example 4 and Example 2 showed lower static water droplet contact angles, indicating that the low-temperature plasma treatment and nano-silicate particle composite coating adopted by the present invention significantly enhanced the hydrophilicity of the fabric, which was beneficial to the bonding of the coating to the substrate. The test results of the porous structure of the coating showed that the example samples had higher specific surface area and pore volume, proving that the porosity control of the composite coating and the nanoparticle dispersion process effectively improved the microstructural uniformity and porosity of the coating. The hydrophilicity changed little after 72 hours, reflecting good stability. In contrast, the comparative sample had poor hydrophilicity, and the specific surface area and pore volume of the coating were significantly reduced, reflecting the adverse effects of not adopting the process of the present invention on the coating structure and surface properties. In summary, the experiment verified the technical advantages of the present invention in controlling the hydrophilicity of the fabric surface and the porous structure of the coating.

[0105] The above shows and describes the basic principles, main features and advantages of the present invention; those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected; the scope of protection claimed in the present invention is defined by the attached claims and their equivalents.

Claims

1. A lightweight thermal insulation fabric, characterized in that: The invention relates to a fabric matrix comprising polyester fibers and aramid fibers interwoven at a mass ratio of 70:30, wherein the fiber diameter of the polyester fibers is 12 to 16 microns, the fiber diameter of the aramid fibers is 10 to 14 microns, and the fabric density is 180 to 220 fibers per 10 cm; The surface of the fabric substrate is coated with a composite coating, which is composed of nanoporous silicate particles chemically modified with an aminosilane coupling agent and a cross-linked two-component waterborne polyurethane resin. The nanoporous silicate particles have a particle size of 50 to 200 nanometers and a thickness of 5 to 15 microns. The cross-linked two-component waterborne polyurethane resin is prepared by mixing an isocyanate component and a polyether polyol component in a weight ratio of 1 to 1.

1. Ultrasonic-assisted dispersion technology is used to uniformly disperse the nanoporous silicate particles in the cross-linked two-component waterborne polyurethane resin. The composite coating has a nanoporous silicate particle mass fraction of 30 to 50 percent and a porosity of 40 to 60 percent; The nanoporous silicate particles are prepared by a sol-gel method, the pH value of the sol is controlled in the range of 3 to 5, and the surface of the particles is modified by using 3-aminopropyltriethoxysilane.

2. A lightweight thermal insulation fabric according to claim 1, characterized in that: The fiber bundle twist of the fabric matrix is ​​250 to 350 turns per meter, and the fabric thickness is 0.25 to 0.35 mm.

3. A method for preparing a lightweight thermal insulation fabric, characterized in that: The method for preparing a lightweight thermal insulation fabric comprises the following steps: S1. The polyester fiber and the aramid fiber are opened and carded in a mass ratio of 70 to 30, and interwoven on a twill loom to form a fabric matrix. The fabric density is controlled at 180 to 220 strands per 10 cm, the fiber bundle twist is controlled at 250 to 350 turns per meter, and the fabric thickness is controlled at 0.25 to 0.35 mm. S2 the fabric substrate is subjected to low-temperature plasma treatment, the gas used is a mixture of oxygen and nitrogen, the processing power is 100 to 200 watts, the processing time is 5 to 15 minutes; S3. preparing a composite coating solution comprising nanoporous silicate particles modified with an aminosilane coupling agent and a cross-linked two-component waterborne polyurethane resin, wherein the nanoporous silicate particles are prepared by a sol-gel method, the pH value of the sol is controlled in the range of 3 to 5, the particle surface is surface-modified with 3-aminopropyltriethoxysilane, the nanoporous silicate particles have a particle size of 50 to 200 nm, and the particle content accounts for 30 to 50 percent by mass of the composite coating solution; the cross-linked two-component waterborne polyurethane resin is prepared by mixing an isocyanate component and a polyether polyol component in a weight ratio of 1 to 1.1; S4. Using ultrasound-assisted dispersion technology, an ultrasonic frequency of 20 to 40 kHz for 15 to 25 minutes, the nanoporous silicate particles are uniformly dispersed in a cross-linked two-component aqueous polyurethane resin; S5. The plasma-treated fabric substrate is immersed in the composite coating solution for a period of 5 to 10 minutes; S6. Thermally cure the coating at 80 to 120 degrees Celsius for 15 to 30 minutes under a relative humidity of 40 to 60 percent to form a composite coating having a thickness of 5 to 15 microns and a porosity of 40 to 60 percent.

4. The method for preparing a lightweight thermal insulation fabric according to claim 3, characterized in that: The gelation time during the preparation of the nanoporous silicate particles is controlled to be 12 to 24 hours, and the surface modification treatment time after the particles are formed is 1 to 3 hours.

5. The method for preparing a lightweight thermal insulation fabric according to claim 4, characterized in that: The cross-linked two-component waterborne polyurethane resin is prepared by mixing an isocyanate component and a polyether polyol component in a weight ratio of 1 to 1.1, and the mixing shear rate is controlled at 500 to 700 per second.

6. The method for preparing a lightweight thermal insulation fabric according to claim 5, characterized in that: During the thermal curing process, the distance between the fabric substrate and the heating source is 10 to 15 cm. After curing, there is no crack on the coating surface, and the bonding strength between the coating and the fabric substrate is greater than 3 MPa.

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