Photo-thermal enhanced waterproof breathable composite fabric and preparation method thereof

Abstract

The invention belongs to the technical field of fabrics, and discloses a photo-thermal enhanced waterproof breathable composite fabric and a preparation method thereof.The composite fabric comprises an outer layer fabric, a porous photo-thermal fiber film, a waterproof breathable microporous film and a lining layer; comprising the following steps: uniformly dispersing a photo-thermal nano material in an organic solvent, adding thermoplastic polyurethane, stirring to obtain a mixed spinning solution, and carrying out electrostatic spinning to obtain the porous photo-thermal fiber membrane, the outer layer fabric, the porous photo-thermal fiber film, the waterproof breathable microporous film and the lining layer are sequentially overlapped and bonded through a hot melt adhesive in a point-shaped or grid-shaped coating mode, and then the composite fabric is obtained through hot press forming and cooling shaping; wherein the photo-thermal nano material is reduced graphene oxide modified by polydopamine or MXene (Metalene). Solar energy can be actively utilized to prevent the microporous film from freezing, and heating is assisted, so that performance self-adaption and lasting stability of the fabric in an extreme environment are realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fabrics, and particularly relates to a light-heat enhanced waterproof and breathable composite fabric and a preparation method thereof. BACKGROUND

[0002] At present, high-end outdoor clothing generally adopts a laminated fabric taking a microporous film (such as an ePTFE film) as a core to realize waterproof and breathable functions. This kind of fabric relies on the microporous structure with a pore size between water vapor molecules and liquid water droplets to allow sweat to be discharged while blocking external rainwater. However, in a cold and humid environment, water vapor is prone to condensation and icing when passing through the microporous film, resulting in a sharp decrease or even failure of the breathable performance, and the wearer faces the risk of wet and cold and temperature loss. Existing solutions, such as an electric heating film, can provide heat but need an external power supply, and have problems such as being heavy, poor safety, and affecting the flexibility of the clothing. Therefore, it has become an urgent need in the field to develop an outdoor fabric that can actively maintain the temperature of the microporous film, prevent icing, and improve thermal comfort without relying on external energy, sacrificing the original waterproof and breathable performance, and durability. SUMMARY

[0003] In view of the deficiencies of the prior art, the application provides a light-heat enhanced waterproof and breathable composite fabric and a preparation method thereof, so as to endow the fabric with the ability to actively utilize solar energy to prevent the microporous film from icing and assist in heating without relying on external energy, sacrificing the original waterproof and breathable performance, and durability, so as to realize the performance self-adaptation and persistent stability of the fabric in extreme environments.

[0004] The technical scheme provided by the application is as follows:

[0005] The application provides a preparation method of a light-heat enhanced waterproof and breathable composite fabric, and the composite fabric comprises an outer fabric, a porous light-heat fiber film, a waterproof and breathable microporous film, and an inner lining. The preparation method comprises the following steps: The light-heat nanomaterial is uniformly dispersed in an organic solvent, thermoplastic polyurethane is added, and stirring is performed to obtain a mixed spinning solution, and the porous light-heat fiber film is obtained through electrospinning. The outer fabric, the porous light-heat fiber film, the waterproof and breathable microporous film, and the inner lining are sequentially laminated, and hot melt adhesive is used to perform point or grid coating to perform bonding, and then the composite fabric is obtained through hot pressing and cooling and shaping. The light-heat nanomaterial is polydopamine modified reduced graphene oxide or MXene.

[0006] Further, when the photothermal nanomaterial is polydopamine modified reduced graphene oxide, the mass ratio of the photothermal nanomaterial in the thermoplastic polyurethane is 3-8%, and when the photothermal nanomaterial is MXene, the mass ratio of the photothermal nanomaterial in the thermoplastic polyurethane is 2-5%.

[0007] Further, the average diameter of the fibers of the porous photothermal fiber membrane is 300-800 nm, the gram weight is 3-10 g / m 2 , the thickness is 0.02-0.05 mm, and the porosity is ≥80%.

[0008] Further, in the electrospinning process, the spinning head voltage is adjusted to 15-25 kV, the distance between the spinning head and the electrospinning receiver is 12-20 cm, and the flow rate of the spinning solution is controlled at 0.8-1.5 mL / h.

[0009] Further, the organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide and tetrahydrofuran.

[0010] Further, the hot melt adhesive is a polyurethane-based hot melt adhesive, and the bonding area ratio is controlled at 10-30%.

[0011] Further, in the hot pressing process, the hot pressing temperature is 150-180 DEG C, and the operating pressure is 0.4-0.8 MPa.

[0012] Further, the outer fabric is a waterproof finished nylon or polyester fabric, the gram weight is 30-50 g / m 2 , the thickness is 0.05-0.08 mm, the yarn fineness of the nylon or polyester is 20-30D, the warp density is 180-220 threads / inch, the weft density is 120-160 threads / inch, and the visible light and near-infrared light transmittance of the outer fabric is ≥70%; the inner lining layer is a polyester or nylon mesh knitted fabric, the gram weight is 20-40 g / m 2 , and the thickness is 0.15-0.25 mm.

[0013] Further, the waterproof and breathable microporous film is an expanded polytetrafluoroethylene film or a thermoplastic polyurethane microporous film, the gram weight is 5-15 g / m 2 , the thickness is 0.01-0.03 mm, the hydrostatic pressure resistance is ≥20,000 mmH2O, and the evaporation resistance is ≤3 m 2 ·Pa / W.

[0014] The application also provides a photothermal enhanced waterproof and breathable composite fabric prepared by the above preparation method.

[0015] Advantages

[0016] This invention uses a porous photothermal fiber membrane to actively insulate the waterproof and breathable membrane, solving the problem of breathability failure caused by low-temperature freezing and greatly improving the reliability of equipment in extreme environments. Without the need for an external power source, it replenishes the wearer's heat and effectively ensures and promotes the expulsion of sweat by maintaining the membrane temperature, preventing ice blockage, and increasing the vapor pressure difference between the inside and outside of the garment, thus significantly improving thermal comfort. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the composite fabric of the present invention, wherein (a) is the outer fabric; (b) is a porous photothermal fiber membrane; (c) is a waterproof and breathable microporous membrane; and (d) is the inner lining layer.

[0018] Figure 2 This is a flowchart illustrating the preparation process of the composite fabric of the present invention. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to specific embodiments. The following embodiments are not intended to limit the present invention, but only to illustrate the present invention. Unless otherwise specified, the experimental methods used in the following embodiments are generally performed under conventional conditions. Unless otherwise specified, the materials and reagents used in the following embodiments are commercially available.

[0020] The following are some of the reagent models and manufacturers used in this embodiment:

[0021] Thermoplastic polyurethane (TPU): Selected from one of the following: BASF's Elastollan® 1185A series, Lubrizol's Estane® 58xxx series, and Huafeng Group's HT-1185A series.

[0022] Photothermal material: PDA-rGO: Graphene oxide (GO) can be prepared via the Hummers method, then modified by self-polymerization into PDA in Tris-HCl buffer containing dopamine hydrochloride (purchased from Sigma-Aldrich), followed by in-situ reduction. The preparation steps are as follows:

[0023] Preparation of graphene oxide (GO): A modified Hummers method was used. 3 g of natural flake graphite (325 mesh) and 18 g of KMnO4 were slowly added to 360 mL of a mixture of 98% H2SO4 / 85% H3PO4 (9:1 volume ratio), and the mixture was stirred at 50 °C for 12 hours. After the reaction was complete, 400 mL of ice water and 30 mL of H2O2 (30%) were added, and the mixture was centrifuged and washed until pH≈5. Graphene oxide (GO) was then freeze-dried.

[0024] PDA Modification and In-situ Reduction: 100 mg of GO was dispersed in 200 mL of Tris-HCl buffer (pH=8.5) and sonicated for 30 minutes. 200 mg of dopamine hydrochloride (Sigma-Aldrich) was added, and the mixture was magnetically stirred at 25 °C for 24 hours. After the reaction was complete, the precipitate was collected by centrifugation, washed three times with deionized water, and dried under vacuum at 60 °C to obtain polydopamine-modified reduced graphene oxide (PDA-rGO).

[0025] Photothermal material: MXene (Ti3C2T) x ): Prepared by selective etching of MAX phase ceramics (such as Ti3AlC2, purchased from China 11 Technology Co., Ltd., catalog number YC / T3A2C).

[0026] MXene (Ti3C2T x Preparation of Ti3AlC2 MAX phase powder: 1.0 g of Ti3AlC2 MAX phase powder was weighed and slowly added to 20 mL of hydrochloric acid solution (9 mol / L). The mixture was stirred in an ice-water bath for 10 minutes. Subsequently, 1.0 g of lithium fluoride (LiF) was added in batches while stirring. The reaction system was transferred to a 35℃ constant temperature water bath and magnetically stirred continuously for 24 hours to selectively etch away the Al layer. After the reaction, the product was washed multiple times with deionized water (3500 rpm, 10 minutes each time) until the pH of the supernatant was higher than 6. Finally, the washed precipitate was dispersed in 50 mL of deionized water and sonicated for 1 hour (300W) under argon protection. After centrifugation, the upper black colloidal dispersion was collected and freeze-dried to obtain multilayer Ti3C2T. x MXene nanosheets.

[0027] Organic solvent: N,N-dimethylformamide (DMF), analytical grade, purchased from Sinopharm Chemical Reagent Co., Ltd.

[0028] Durable water-repellent (DWR) finishing agent: Choose a fluorocarbon compound finishing agent, such as Chemours' Teflon® Eco Dry series or Archroma's Nuva® N series. Specifically, use Nuva® N2114 Liq at a dosage of 40-60 g / L.

[0029] Hot melt adhesive: Polyurethane (PU) based hot melt adhesive powder, selected from Evonik's Vestamelt® X series or Henkel's Technomelt® series.

[0030] like Figure 1 and Figure 2As shown, this embodiment of the invention provides a method for preparing a photothermal enhanced waterproof and breathable composite fabric, wherein the composite fabric includes an outer fabric, a porous photothermal fiber membrane, a waterproof and breathable microporous membrane, and an inner lining layer. The preparation method includes the following steps: Photothermal nanomaterials are uniformly dispersed in an organic solvent, thermoplastic polyurethane is added, and the mixture is stirred to obtain a mixed spinning solution. The porous photothermal fiber membrane is obtained by electrospinning. The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane and inner lining layer are stacked in sequence and bonded with hot melt adhesive through dot or grid coating. The composite fabric is then obtained by hot pressing and cooling. The photothermal nanomaterial is polydopamine-modified reduced graphene oxide or MXene.

[0031] Specifically, the core of the preparation method of this invention lies in introducing a layer of functional porous photothermal fiber membrane and integrating it with a traditional structure through an optimized lamination process to form a synergistic whole. For example... Figure 1 The composite fabric consists of (a) an outer fabric, (b) a porous photothermal fiber membrane, (c) a waterproof and breathable microporous membrane, and (d) an inner lining layer, from the outside to the inside.

[0032] In this embodiment, when the photothermal nanomaterial is polydopamine-modified reduced graphene oxide, the mass percentage of the photothermal nanomaterial in the thermoplastic polyurethane is 3-8%, and when the photothermal nanomaterial is MXene, the mass percentage of the photothermal nanomaterial in the thermoplastic polyurethane is 2-5%.

[0033] In this embodiment, the porous photothermal fiber membrane has an average fiber diameter of 300~800 nm and a basis weight of 3~10 g / m³. 2 The thickness is 0.02~0.05 mm and the porosity is ≥80%.

[0034] Specifically, the porous photothermal fiber membrane is fabricated using thermoplastic polyurethane (TPU) as the matrix and photothermal nanomaterials via electrospinning. The average fiber diameter of the porous photothermal fiber membrane is controlled between 300 and 800 nm, forming a three-dimensional microporous network structure with interconnected fibers and a porosity exceeding 80%, ensuring extremely low water vapor transport resistance. The photothermal material is preferably polydopamine-modified reduced graphene oxide (PDA-rGO) or MXene (Ti3C2T). xThe nanosheets consist of PDA-rGO at a mass ratio of 3%-8% of TPU and MXene at 2%-5%. This ratio ensures efficient photothermal conversion (the membrane surface temperature rise can reach 20-40°C under standard AM 1.5G solar irradiation) while maintaining good spinnability and mechanical properties of the fibers. The porous photothermal fiber membrane, acting as a planar heat source, primarily absorbs light energy to generate heat and directly heats adjacent waterproof and breathable microporous membranes.

[0035] In this embodiment, during the electrospinning process, the spinneret voltage is adjusted to 15~25 kV, the distance between the spinneret and the electrospinning receiver is 12~20 cm, and the flow rate of the spinning solution is controlled at 0.8~1.5 mL / h.

[0036] Specifically, at a temperature of 25°C and a humidity of 40%, the mixed spinning solution is injected into an electrospinning device. Under the conditions of voltage (15~25 kV, finely adjusted according to the average fiber diameter), receiving distance (12~20 cm), and flow rate (0.8~1.5 mL / h), the fibers are collected on the receiving roller to form a porous photothermal fiber membrane.

[0037] In this embodiment, the organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran.

[0038] In this embodiment, the hot melt adhesive is a polyurethane-based hot melt adhesive, and the bonding area ratio is controlled between 10% and 30%.

[0039] In this embodiment, during the hot pressing process, the hot pressing temperature is 150~180℃ and the operating pressure is 0.4~0.8MPa.

[0040] Specifically, the layers are laminated using a dot-matrix hot melt adhesive bonding process. This process uses polyurethane (PU)-based hot melt adhesive, applied in a discontinuous dot or grid pattern (with the bonding area controlled at 10-30%), followed by hot pressing at temperature (150-180°C) and pressure (0.4-0.8 MPa). This dot-matrix bonding method maximizes the preservation of the pore connectivity between the fabric layers, thus ensuring the high breathability of the final composite fabric.

[0041] In this embodiment, the outer fabric is a waterproof-finished nylon or polyester fabric with a weight of 30-50 g / m² and a thickness of 0.05-0.08 mm. The nylon or polyester yarn fineness is 20-30D, the warp density is 180-220 threads / inch, the weft density is 120-160 threads / inch, and the visible and near-infrared light transmittance of the outer fabric is ≥70%. The inner lining is a polyester or nylon mesh knitted fabric with a weight of 20-40 g / m². 2With a thickness of 0.15~0.25 mm, it mainly serves to protect and enhance the skin feel.

[0042] Specifically, the outer fabric is made of high-density nylon or polyester (20D or 30D specifications), and the surface is treated with durable water-repellent (DWR). The DWR concentration is 40~60 g / L, the rolling pressure is 0.2~0.4 MPa, the pick-and-place rate is 40%-60%, the drying temperature is 150~180℃, and the drying time is 1~3 min. Its main function is abrasion resistance and protection, and after treatment, the visible light and near-infrared light transmittance is ≥70%, ensuring that sufficient light can reach the inner photothermal fiber membrane.

[0043] In this embodiment, the waterproof and breathable microporous membrane is an expanded polytetrafluoroethylene (PTFE) film or a thermoplastic polyurethane (TPU) microporous membrane, with a basis weight of 5~15 g / m², a thickness of 0.01~0.03 mm, a hydrostatic pressure resistance ≥20000 mmH₂O, and an evaporative thermal resistance ≤3 m. 2 ·Pa / W.

[0044] Specifically, the waterproof and breathable microporous membrane is an expanded polytetrafluoroethylene (ePTFE) film or a thermoplastic polyurethane (TPU) microporous membrane. Its key performance parameters are: hydrostatic pressure resistance ≥20000 mmH2O, evaporative thermal resistance (RET value) ≤3 m²·Pa / W (or moisture permeability MVTR ≥20000 g / m² / 24h), and it has strong waterproof and breathable properties.

[0045] This invention also provides a photothermal enhanced waterproof and breathable composite fabric, which is made by the above-described preparation method. The overall thickness of the composite fabric can be controlled between 0.25 and 0.5 mm, and the surface weight is in the range of 90 to 130 g / m², meeting the lightweight requirements of high-end outdoor clothing.

[0046] The following detailed description of the preparation method of the photothermal enhanced waterproof and breathable composite fabric provided by the present invention, with reference to the embodiments (see Table 1), should not be construed as limiting the scope of protection of the present invention.

[0047] Example 1

[0048] This invention provides a method for preparing a photothermal enhanced waterproof and breathable composite fabric, specifically including the following steps:

[0049] (1) Preparation of porous photothermal fiber membrane

[0050] Preparation of photothermal spinning solution: 80 mg of PDA-rGO (self-made) was dispersed in 10 g of DMF and sonicated for 1 hour. 1.96 g of TPU particles (BASF, Elastollan® 1185A) were added and magnetically stirred for 12 hours to form a homogeneous and spinnable mixed spinning solution (PDA-rGO content was 4% of TPU).

[0051] Electrospinning: Under conditions of 25℃ and 40% humidity, the spinning solution was injected into a syringe. The voltage was set to 18 kV, the receiving distance to 15 cm, and the flow rate to 1.0 mL / h. A roller receiver with a width of 20 cm and a rotation speed of 100 rpm was used for receiving. By controlling the spinning time, a porous photothermal fiber membrane was formed, and the basis weight was measured to be 5.5 g / m³. 2 The thickness is 0.03 mm, and the porosity is 85% as measured by mercury intrusion porosimetry. The average fiber diameter of the porous photothermal fiber membrane is controlled at 500 nm.

[0052] (2) Fabric composite

[0053] The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane, and inner lining layer are sequentially layered and bonded together using polyurethane-based hot melt adhesive powder (Vestamelt® X1010) with 15% of the area bonded by dots. The bonding is carried out by hot pressing at 160°C and 0.5 MPa, followed by cooling and setting to obtain the composite fabric (the overall thickness of the composite fabric is 0.32 mm, and the surface weight is 115 g / m²). 2 The outer layer fabric is 20D nylon fabric (38 g / m²). 2 The outer fabric is 0.06 mm thick, with a warp density of 200 threads / inch and a weft density of 140 threads / inch. The visible and near-infrared light transmittance of the outer fabric is ≥70%. It undergoes DWR finishing using Nuva® N2114 Liq (50 g / L). The waterproof and breathable microporous membrane is an ePTFE membrane (8 g / m²). 2 Thickness 0.015 mm); inner lining is polyester mesh fabric (weight 30 g / m²). 2 (thickness 0.20 mm).

[0054] Example 2

[0055] This invention provides a method for preparing a photothermal enhanced waterproof and breathable composite fabric, specifically including the following steps:

[0056] (1) Preparation of porous photothermal fiber membrane

[0057] Preparation of photothermal spinning solution: 60 mg PDA-rGO (prepared according to the above method) was dispersed in 10 g DMF and sonicated for 1 hour. 1.98 g TPU particles (BASF, Elastollan® 1185A) were added and magnetically stirred for 12 hours to form a homogeneous and spinnable mixed spinning solution (PDA-rGO content was 3% of TPU).

[0058] Electrospinning: Under an environment of 25℃ and 40% humidity, the voltage was set to 17 kV, the receiving distance to 14 cm, the flow rate to 0.9 mL / h, and a roller receiver with a width of 20 cm and a rotation speed of 100 rpm was used for receiving. By controlling the spinning time, the basis weight was measured to be 4.8 g / m², the thickness to be 0.028 mm, the porosity to be 83%, and the average fiber diameter to be 450 nm.

[0059] (2) Fabric composite

[0060] The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane, and inner lining layer are sequentially stacked and bonded together using polyurethane-based hot melt adhesive powder (Vestamelt® X1010) with a dot bonding area of ​​12%. The bonding is carried out by hot pressing at 155°C and 0.45 MPa, followed by cooling and setting to obtain the composite fabric (overall thickness of 0.30 mm and surface weight of 108 g / m²). The materials of each layer are the same as in Example 1.

[0061] Example 3

[0062] This invention provides a method for preparing a photothermal enhanced waterproof and breathable composite fabric, specifically including the following steps:

[0063] (1) Preparation of porous photothermal fiber membrane

[0064] Preparation of photothermal spinning solution: 160 mg PDA-rGO (prepared as described above) was dispersed in 10 g DMF and sonicated for 1.5 hours. 1.92 g TPU particles (BASF, Elastollan® 1185A) were added and magnetically stirred for 14 hours to form a homogeneous, spinnable mixed spinning solution (PDA-rGO content was 8% of TPU).

[0065] Electrospinning: Under an environment of 25℃ and 40% humidity, with a voltage of 20 kV, a receiving distance of 16 cm, a flow rate of 1.2 mL / h, and a roller receiver with a width of 20 cm and a rotation speed of 100 rpm, a porous photothermal fiber membrane was formed by controlling the spinning time. The measured basis weight was 6.8 g / m², the thickness was 0.038 mm, the porosity was 87%, and the average fiber diameter was 600 nm.

[0066] (2) Fabric composite

[0067] The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane, and inner lining layer were sequentially stacked and bonded together using polyurethane-based hot melt adhesive powder (Vestamelt® X1010) with 18% of the dot bonding area. The bonding was carried out by hot pressing at 165°C and 0.55 MPa, followed by cooling and setting to obtain the composite fabric (overall thickness of 0.34 mm and surface weight of 118 g / m²). The materials of each layer are the same as in Example 1.

[0068] Example 4

[0069] This invention provides a method for preparing a photothermal enhanced waterproof and breathable composite fabric, specifically including the following steps:

[0070] (1) Preparation of porous photothermal fiber membrane

[0071] Preparation of photothermal spinning solution: 40 mg MXene (Ti3C2T) was added to the solution. x The MXene (prepared as described above) was dispersed in 10 g of DMF and sonicated for 1 hour. 1.98 g of TPU particles (BASF, Elastollan® 1185A) were added and magnetically stirred for 12 hours to form a homogeneous, spinnable mixed spinning solution (MXene content of 2% of TPU).

[0072] Electrospinning: Under conditions of 25℃ and 40% humidity, with a voltage of 16 kV, a receiving distance of 13 cm, and a flow rate of 0.8 mL / h, the film was collected on a receiving roller for 4 hours to form a porous photothermal fiber membrane. The basis weight was measured to be 4.2 g / m³. 2 The fiber has a thickness of 0.025 mm, a porosity of 82%, and an average fiber diameter of 400 nm.

[0073] (2) Fabric composite

[0074] The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane, and inner lining layer were sequentially stacked and bonded together using polyurethane-based hot melt adhesive powder (Vestamelt® X1010) with 10% of the area bonded by dots. The bonding was carried out by hot pressing at 150°C and 0.4 MPa, followed by cooling and setting to obtain the composite fabric (overall thickness of 0.29 mm and surface weight of 106 g / m²). The materials of each layer are the same as in Example 1.

[0075] Example 5

[0076] This invention provides a method for preparing a photothermal enhanced waterproof and breathable composite fabric, specifically including the following steps:

[0077] (1) Preparation of porous photothermal fiber membrane

[0078] Preparation of photothermal spinning solution: 100 mg MXene (Ti3C2T) x The MXene (prepared as described above) was dispersed in 10 g DMF and sonicated for 1.5 hours. 1.95 g TPU particles (BASF, Elastollan® 1185A) were added and magnetically stirred for 14 hours to form a homogeneous, spinnable mixed spinning solution (MXene content of 5% of TPU).

[0079] Electrospinning: Under an environment of 25℃ and 40% humidity, with a voltage of 22 kV, a receiving distance of 18 cm, a flow rate of 1.4 mL / h, and a roller receiver with a width of 20 cm and a rotation speed of 100 rpm, a porous photothermal fiber membrane was formed by controlling the spinning time. The measured basis weight was 6.2 g / m², the thickness was 0.036 mm, the porosity was 85%, and the average fiber diameter was 580 nm.

[0080] (2) Fabric composite

[0081] The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane, and inner lining layer were sequentially stacked and hot-pressed at 170°C and 0.6 MPa using polyurethane-based hot melt adhesive powder (Vestamelt® X1010) with 20% of the area bonded by dots. The composite fabric (overall thickness 0.33 mm, surface weight 116 g / m²) was then cooled and set to obtain the final product. The materials of each layer are the same as in Example 1.

[0082] Example 6

[0083] This invention provides a method for preparing a composite fabric using MXene as a photothermal material, the specific steps of which are as follows:

[0084] (1) Preparation of porous photothermal fiber membrane

[0085] Preparation of photothermal spinning solution: 80 mg MXene (Ti3C2T) was added to the solution. x The MXene (prepared as described above) was dispersed in 10 g DMF and sonicated for 1 hour. 1.96 g TPU particles (BASF, Elastollan® 1185A) were added and magnetically stirred for 12 hours to form a homogeneous, spinnable mixed spinning solution (MXene content of 4% of TPU).

[0086] Electrospinning: Under an environment of 25℃ and 40% humidity, with a voltage of 20 kV, a receiving distance of 18 cm, a flow rate of 1.2 mL / h, and a roller receiver with a width of 20 cm and a rotation speed of 100 rpm, a porous photothermal fiber membrane was formed by controlling the spinning time. The measured basis weight was 6.0 g / m², the thickness was 0.032 mm, the porosity was 82%, and the average fiber diameter was 550 nm.

[0087] (2) Fabric composite

[0088] The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane, and inner lining layer were sequentially stacked and hot-pressed at 165°C and 0.6 MPa using polyurethane-based hot melt adhesive powder (Vestamelt® X1010) with a 20% mesh bonding area. The composite fabric (overall thickness 0.31 mm, surface weight 114 g / m²) was then cooled and set to obtain the final product. The materials of each layer were the same as in Example 1.

[0089] Comparative Example 1

[0090] The structure is exactly the same as in Example 1, but it does not contain the photothermal material PDA-rGO, that is, it only uses electrospun pure TPU fiber film as the intermediate layer.

[0091] Comparative Example 2.

[0092] The traditional three-layer pressing structure is adopted: outer fabric (same as in Example 1) + waterproof and breathable microporous membrane (same as in Example 1) + inner lining (same as in Example 1), with no photothermal fiber membrane in the middle.

[0093] The electrospinning parameters (voltage, receiving distance, flow rate) need to be optimized in conjunction with the viscosity, conductivity and required fiber diameter of the spinning solution. The parameters in the above examples are the preferred conditions under the corresponding ratios.

[0094] Comparison of Test Methods and Results

[0095] Test method:

[0096] Photothermal conversion performance: The surface temperature rise curve of the sample was recorded using an infrared thermal imager under a standard AM 1.5G (1000 W / m²) artificial sunlight source.

[0097] Hydrostatic pressure resistance: Tested according to standard GB / T 4744-2013.

[0098] Moisture permeability: Moisture transmittance (MVTR) was tested according to standard GB / T 12704.2-2009 (moisture absorption method).

[0099] Low-temperature anti-icing performance: The sample was covered with the mouth of a cup containing 40℃ warm water (which generates steam), and placed in an environmental chamber at -10℃ and 90% humidity. The change in the mass of the cup (simulating the amount of sweat excretion) and the freezing condition of the membrane surface were recorded within 1 hour.

[0100] Washability: Following standard AATCC 135, the retention rate of hydrostatic pressure resistance and moisture permeability was tested after 5 household washes.

[0101] Table 1 Comparison of Performance Test Results

[0102]

[0103] As shown in Table 1, the photothermal temperature rise is positively correlated with the content of the photothermal material: the temperature rise is lower when the PDA-rGO content is 3% (22℃) and highest when it is 8% (31℃); the temperature rise is lowest when the MXene content is 2% (18℃) and close to the effect of 4% PDA-rGO (26℃) when it is 5%.

[0104] The low-temperature anti-icing performance is consistent with the trend of photothermal temperature rise: the higher the temperature rise, the greater the mass loss, and the better the anti-icing effect.

[0105] The initial performance and durability of all embodiments are superior to those of the comparative examples, demonstrating the effectiveness of the present invention.

[0106] The working mechanism of this invention is as follows: When sunlight (especially the near-infrared portion) penetrates the outer fabric, it is efficiently absorbed by PDA-rGO or MXene in the porous photothermal fiber membrane and converted into heat energy. The membrane rapidly heats up, and the resulting heat acts directly on the waterproof and breathable microporous membrane through thermal conduction, maintaining its surface temperature above freezing even in extremely cold environments. This effectively prevents water vapor condensation and ice blockage of the micropores, ensuring the long-term unobstructed airflow. Simultaneously, this heat radiates inward, providing auxiliary heating for the wearer, enhancing thermal comfort, and increasing the vapor pressure difference between the inside and outside of the garment, further promoting perspiration expulsion.

[0107] The specific embodiments of the present invention have been described in detail above, but the scope of the present invention is not limited to the above embodiments. For those skilled in the art, various adjustments, modifications, or substitutions can be made to the embodiments without departing from the core principles and spirit of the present invention, but these modifications still fall within the protection scope of the present invention.

Claims

1. A method for preparing a photothermal enhanced waterproof and breathable composite fabric, characterized in that, The composite fabric includes an outer fabric, a porous photothermal fiber membrane, a waterproof and breathable microporous membrane, and an inner lining layer. The preparation method includes the following steps: Photothermal nanomaterials are uniformly dispersed in an organic solvent, thermoplastic polyurethane is added, and the mixture is stirred to obtain a mixed spinning solution. The porous photothermal fiber membrane is obtained by electrospinning. The outer fabric, porous photothermal fiber membrane, waterproof and breathable microporous membrane and inner lining layer are stacked in sequence and bonded with hot melt adhesive through dot or grid coating. The composite fabric is then obtained by hot pressing and cooling. The photothermal nanomaterial is polydopamine-modified reduced graphene oxide or MXene.

2. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, When the photothermal nanomaterial is polydopamine-modified reduced graphene oxide, the mass percentage of the photothermal nanomaterial in the thermoplastic polyurethane is 3-8%; when the photothermal nanomaterial is MXene, the mass percentage of the photothermal nanomaterial in the thermoplastic polyurethane is 2-5%.

3. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, The porous photothermal fiber membrane has an average fiber diameter of 300~800 nm and a basis weight of 3~10 g / m³. 2 The thickness is 0.02~0.05 mm and the porosity is ≥80%.

4. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, During electrospinning, the spinneret voltage is adjusted to 15~25 kV, the distance between the spinneret and the electrospinning receiver is 12~20 cm, and the flow rate of the spinning solution is controlled at 0.8~1.5 mL / h.

5. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, The organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran.

6. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, The hot melt adhesive is a polyurethane-based hot melt adhesive, and the bonding area ratio is controlled between 10% and 30%.

7. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, During the hot pressing process, the hot pressing temperature is 150~180℃ and the operating pressure is 0.4~0.8 MPa.

8. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, The outer fabric is a waterproof-treated nylon or polyester fabric with a weight of 30-50 g / m². 2 The outer fabric has a thickness of 0.05~0.08 mm, a yarn fineness of 20~30D for nylon or polyester, a warp density of 180~220 threads / inch, a weft density of 120~160 threads / inch, and a visible and near-infrared light transmittance of ≥70%. The inner lining is a polyester or nylon mesh knitted fabric with a weight of 20~40 g / m². 2 The thickness is 0.15~0.25 mm.

9. The method for preparing the photothermal enhanced waterproof and breathable composite fabric according to claim 1, characterized in that, The waterproof and breathable microporous membrane is an expanded polytetrafluoroethylene film or a thermoplastic polyurethane microporous membrane, with a basis weight of 5~15 g / m³. 2 Thickness of 0.01~0.03 mm, hydrostatic pressure resistance ≥20000 mmH2O, evaporative thermal resistance ≤3 m 2 ·Pa / W.

10. A photothermal enhanced waterproof and breathable composite fabric, characterized in that, It is prepared by the method described in any one of claims 1-9.

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