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CN-122013528-A - Light heat-insulating fabric and preparation method thereof

CN122013528ACN 122013528 ACN122013528 ACN 122013528ACN-122013528-A

Abstract

The invention belongs to the technical fields of functional textile materials, nano material preparation processes and thermal protection engineering, and particularly relates to a light heat-insulating fabric and a preparation method thereof, aiming at the problem that the performances of the existing fabric such as light weight, high heat insulation and the like are mutually restricted, the invention utilizes wet spinning to finish fiber forming and chemical imidization of polyamic acid precursor liquid in a coagulating bath containing imidization agents, prepares modified polyimide aerogel composite fibers by supercritical drying, blends the modified polyimide aerogel composite fibers with thermoplastic polymers, performs electrostatic spinning by adding a placeholder, prepares a porous flexible substrate layer, grows in situ on the surface of the substrate fiber by a solvothermal method to construct a heat-insulating layer, and adopts silane coupling agents and epoxy modifiers to perform alternate interface treatment, thereby effectively solving the problem of performance balance.

Inventors

  • FENG WEIXING
  • Ping Xinjie
  • Zhang Jiebei
  • XU TIANYANG
  • ZHOU LI
  • SONG HUABING

Assignees

  • 浙江玛雅布业有限公司

Dates

Publication Date
20260512
Application Date
20260225

Claims (10)

  1. 1. The preparation method of the light heat-insulating fabric comprises the steps of substrate preparation, functional layer preparation and post-treatment, and is characterized in that: The preparation of the substrate comprises the steps of preparing a composite fiber substrate from polyimide-aerogel composite fibers and thermoplastic polyurethane through a coaxial electrostatic spinning process, wherein sodium chloride placeholder is also added to form a pore channel structure, preparing the functional layer, namely preparing ZIF-8 nano crystal grains on the surface of the fibers in situ to obtain a functional substrate after the composite fiber substrate is pretreated by ethanol, and immersing the functional substrate into KH-550 solution for pre-curing and then immersing the functional substrate into polyethylene glycol diglycidyl ether for chemical crosslinking.
  2. 2. The method for preparing the light heat-insulating fabric according to claim 1, comprising the following steps: S1, preparing composite fibers; s11, dissolving p-phenylenediamine in a proper amount of N, N-dimethylacetamide solvent, cooling in an ice water bath, adding 3,3', 4' -biphenyl tetracarboxylic dianhydride while stirring, filtering, and defoaming to obtain polyamic acid spinning solution; S12, adding acetic anhydride and triethylamine into acetone, stirring, and cooling to room temperature to obtain a coagulating bath; S13, pressing the polyamide acid spinning solution prepared in the step S11 into the coagulating bath prepared in the step S12 through spinning, staying for 10min, then drafting, soaking, supercritical drying and chopping to obtain modified polyimide-aerogel composite fibers; S2, preparing a flexible substrate layer; S21, adding thermoplastic polyurethane into a mixed solvent of N, N-dimethylformamide and tetrahydrofuran in a volume ratio of 1:1, and stirring to obtain a core layer solution, adding the modified polyimide-aerogel composite fiber prepared in the S13 into the mixed solvent of N, N-dimethylformamide and tetrahydrofuran in a volume ratio of 1:1, shearing and emulsifying, adding sodium chloride crystal powder, stirring at a low speed, standing and defoaming to obtain a sheath layer solution; S22, spinning the core layer solution and the sheath layer solution prepared in the step S21 through a coaxial nozzle to prepare composite fiber non-woven fabric, then placing the composite fiber non-woven fabric in deionized water with the temperature of 50 ℃, stirring, and drying to obtain a flexible substrate layer; S3, preparing a heat insulation functional layer; s31, immersing the flexible substrate layer prepared in the S22 into absolute ethyl alcohol for wetting, and then transferring the flexible substrate layer into deionized water to displace out the alcohol to obtain a pretreated flexible substrate layer; S32, adding 2-methylimidazole and carboxylated nanocellulose into a mixed solution of methanol and water in a volume ratio of 1:1, stirring, performing ultrasonic treatment, then adding a zinc nitrate solution, and continuously stirring to obtain a mixed precursor solution; s33, immersing the pretreated flexible substrate layer prepared in the step S31 into the mixed precursor solution prepared in the step S32, heating for reaction, cooling to room temperature, washing, replacing, and drying by supercritical CO 2 to obtain a functional substrate with a heat insulation layer; s4, interface strengthening treatment; s41, immersing the functional substrate of the heat insulation layer prepared in the step S33 into KH-550 solution for 15min, and then performing heat treatment at 80 ℃ for 15min to obtain a pre-cured material; s42, immersing the pre-cured material prepared in the S41 in a polyethylene glycol diglycidyl ether solution for 20min, and then performing heat treatment at 100 ℃ for 30min; And S43, circularly executing the steps S41 and S42 for 1-3 times, and then placing the fabric at 85 ℃ for 60min to obtain the fabric with reinforced interface.
  3. 3. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: S11, wherein the molar ratio of the p-phenylenediamine to the 3,3', 4' -biphenyl tetracarboxylic dianhydride is 1:1; s11, the solid content of the polyamide acid spinning solution is 6-12%; s12, wherein the mass concentration of acetic anhydride is 10-30%, and the volume concentration of triethylamine is 5-15%.
  4. 4. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: S13, soaking for 5-8 times by adopting ethanol and deionized water; And S13, supercritical drying, wherein the parameter setting is that the drying medium is CO 2 , the temperature is 40 ℃ and the pressure is 10MPa.
  5. 5. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: the stirring step S21 is carried out, wherein the parameter setting is that the temperature is 50-60 ℃, the rotating speed is 300-600 rpm, and the duration is 2-6 h; S21, setting parameters of shear emulsification, namely, rotating speed 9000-11000 rpm and duration 10-20 min; S21, setting parameters of the low-speed stirring, namely, rotating speed of 100-300 rpm and duration of 1-2 hours; S21, wherein the thermoplastic polyurethane accounts for 70-90% of the effective solid mass in the core layer solution and the sheath layer solution, the modified polyimide-aerogel composite fiber accounts for 10-30% of the effective solid mass in the core layer solution and the sheath layer solution, and the sodium chloride crystal powder accounts for 10-30% of the total mass of the core layer solution and the sheath layer solution; The spinning method is characterized in that the spinning parameters are set, wherein the core layer advancing speed is 0.1-1 mL/h, the sheath layer advancing speed is 0.5-3 mL/h, the working voltage is 15-25 kV, the receiving distance is 12-20 cm, the temperature is 20-30 ℃, and the relative humidity is 40%.
  6. 6. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: the spinning is characterized in that parameters of S22 are set, wherein the core layer advancing speed is 0.1-1 mL/h, the sheath layer advancing speed is 0.5-3 mL/h, the working voltage is 15-25 kV, the receiving distance is 12-20 cm, the temperature is 20-30 ℃, and the relative humidity is 40%; And S22, setting parameters, namely, setting the temperature to be 60-80 ℃ and the duration to be 12-24 hours.
  7. 7. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: s32, wherein the molar ratio of the 2-methylimidazole to the zinc nitrate is 4:1-8:1; The carboxylated nanocellulose in S32 has a mass ratio to zinc nitrate of 1:5-1:20.
  8. 8. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: The heating reaction is carried out in the step S33, wherein the parameter setting is that the temperature is 60-70 ℃ and the duration is 4-12 h; the substitution of S33 was performed by sequentially immersing in a 50%,75%,95%,100% ethanol solution.
  9. 9. The method for preparing the light heat-insulating fabric according to claim 2, which is characterized in that: the KH-550 solution described in S41, the mass concentration of which is 1%; The polyethylene glycol diglycidyl ether solution of S42 has a mass concentration of 5%.
  10. 10. The lightweight heat-insulating fabric prepared by the preparation method of claims 1-9, which is characterized in that: The heat conduction coefficient of the lightweight heat insulation fabric is less than or equal to 0.045W/m.K, and the tensile strength is more than or equal to 25MPa.

Description

Light heat-insulating fabric and preparation method thereof Technical Field The invention belongs to the technical fields of functional textile materials, nano material preparation processes and thermal protection engineering, and particularly relates to a light heat-insulating fabric and a preparation method thereof. Background With the acceleration of the pace of human exploration for extreme environments and the improvement of comfort requirements for personal thermal protection equipment, the development of novel heat insulation materials with the characteristics of light, thin, warm and strong is becoming a research hotspot in the field of material science. Heat transfer is mainly performed by three modes, heat conduction, heat convection and heat radiation. Traditional heat insulation materials such as cotton, wool, down and other natural fibers (CN 117005086A) mainly rely on a static air layer among the fibers for heat insulation. Although they have good touch and moderate warmth retention properties, in extreme cold environments, in order to achieve adequate warmth retention values, it is often necessary to increase the thickness considerably, resulting in bulky equipment and limited user mobility. In addition, when the ambient wind speed is high or the humidity is increased, the convective heat dissipation and the wet conduction of the materials are dramatically increased, and the heat insulation performance is significantly reduced. Synthetic fibers such as polyester hollow fibers and ultrafine fibers are improved in light weight, but the microscopic pore diameter is still in the micron level, and the Brownian movement of gas molecules cannot be effectively restrained, so that the gas phase heat conductivity coefficient is difficult to break through the limit of air. In addition, these organic fiber materials are generally transparent to infrared thermal radiation, and at high temperature heat sources, radiative heat transfer becomes the dominant mechanism, resulting in failure of the protection. Aerogels, particularly Polyimide (PI) aerogels, are considered the best candidates for thermal insulation in current solid materials due to their unique nanoporous structure, extremely high porosity and extremely low density. However, the application of the PI aerogel to the flexible fabric faces a great technical challenge that an aerogel framework is extremely fine, node connection is fragile, the traditional PI aerogel is extremely easy to break when being bent, stretched or compressed, and cannot bear dynamic deformation in the weaving, cutting and wearing processes of textiles, and in order to solve the brittleness problem, aerogel powder and fibers are often compounded. However, simple physical filling or adhesive bonding can result in weak interfacial binding force between aerogel particles and a fiber matrix, a large amount of the aerogel particles fall off after washing, and the adhesive can block aerogel pores, so that the heat insulation performance is greatly reduced. In order to improve the related performance of the lightweight thermal insulation fabric, some technical approaches have been proposed. For example, electrospinning can produce nanofiber membranes with high specific surface areas, while nanofibers can divide air, the porosity and pore size distribution of conventional electrospun membranes are difficult to achieve aerogel grades, and, for example, magnetron sputtering can produce metal or oxide films that reflect infrared light. However, the deposition of a rigid inorganic film on a loose porous flexible substrate is extremely prone to stress mismatch leading to cracking of the film. In view of the above, there is still a great improvement in the function balance of the heat-insulating fabric in the prior art, and there is a need for a heat-insulating fabric with light weight, high heat insulation, high toughness and flexibility, and a new preparation method thereof. Disclosure of Invention The invention provides a light heat-insulating fabric and a preparation method thereof, aiming at breaking the performance barriers among light weight, high heat insulation, toughness and flexibility. According to the invention, through multi-scale structural design and interface engineering, the mutual restriction between the performances is effectively broken, and the heat-insulating fabric with excellent comprehensive performance is obtained. The specific technical scheme is as follows: A light heat-insulating fabric and a preparation method thereof are as follows: s1, preparing composite fibers. S11, dissolving p-phenylenediamine in a proper amount of N, N-dimethylacetamide solvent, cooling in an ice water bath, adding 3,3', 4' -biphenyl tetracarboxylic dianhydride while stirring, filtering and defoaming to obtain polyamide acid spinning solution. And S12, adding acetic anhydride and triethylamine into acetone, stirring, and cooling to room temperature to obtain a coagulating bath. And S13