Composite phase change fiber fabric

Abstract

The invention relates to the related technical field of composite fiber fabrics, in particular to a composite phase-change fiber fabric which comprises five layers of structures stacked in sequence, a surface layer is warp and weft twisted surface cloth formed by compounding plant source cellulose aerogel, organic phase-change microcapsules, a superfine denier polyester matrix and a carbon-based conductive material, and a surface layer is warp and weft twisted surface cloth formed by compounding plant source cellulose aerogel, organic phase-change microcapsules, a superfine denier polyester matrix and a carbon-based conductive material; through chemical bonding, gradient distribution and bionic structure design, the technical bottlenecks that the heat storage performance of a traditional phase change material is easy to attenuate, moisture permeability and heat preservation are difficult to consider, and a functional layer is easy to peel are systematically solved; the multi-level synergistic effect provides an innovative solution with high stability, wearing comfort and environmental adaptability for the intelligent thermoregulation clothes, and the fabric is obviously superior to the existing single-function or simple composite fabric.

Description

Technical Field

[0001] The present invention belongs to the technical field related to composite fiber fabrics, and more specifically, particularly relates to a composite phase change fiber fabric. Background Art

[0002] With the development of intelligent wearable devices, traditional phase change temperature regulation materials face three major technical bottlenecks: First, physical mixing between the phase change material (such as paraffin) and the matrix easily leads to phase separation and leakage. Second, there is an inherent contradiction between moisture permeability and heat preservation performance. Conventional waterproof and moisture permeable membranes (such as PTFE membranes) have insufficient moisture permeability in high-temperature and high-humidity environments, and increasing the porosity will lead to increased infrared radiation heat dissipation. Third, the introduction of the conductive functional layer often destroys the structural integrity of the fabric.

[0003] Therefore, there is an urgent need to develop a multifunctional composite fiber fabric with high phase change enthalpy retention rate, synergistic enhancement of moisture permeability and heat preservation, and deformable conductive network. Summary of the Invention

[0004] The purpose of the present invention is to provide a composite phase change fiber fabric to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solutions: A composite phase change fiber fabric, including a five-layer structure stacked in sequence, a surface layer, a warp and weft twisted surface cloth formed by compounding plant-derived cellulose aerogel, organic phase change microcapsules, ultrafine denier polyester matrix, and carbon-based conductive material, wherein the raw material mass ratio is: 30-35 parts of plant-derived cellulose aerogel, 20-25 parts of organic phase change microcapsules, 40-50 parts of ultrafine denier polyester matrix, 3-5 parts of carbon-based conductive material; a bonding layer, a thermoplastic polyurethane adhesive layer with sesame seed-shaped openings, and the openings penetrate through the surface layer and the functional layer; a functional layer, a waterproof and moisture permeable microporous membrane containing TPU, PU, and PTFE; a buffer layer, a breathable polyurethane layer with a diamond grid structure; a lining layer, a moisture-absorbing, quick-drying, and tear-resistant polyester Cortex fabric.

[0006] It should be noted that the plant-derived cellulose aerogel in the surface layer constitutes a three-dimensional network skeleton to provide a heat storage space. The phase change microcapsules are fixed in the pores of the three-dimensional network skeleton through chemical bonding. The carbon-based conductive material is coated on the surface of the ultrafine denier polyester fiber in an axial gradient form to form a conductive network, thus constituting a photothermal conversion layer; the sesame seed-shaped openings in the bonding layer ensure unobstructed moisture permeation channels; the functional layer accelerates the discharge of moisture through capillary action; the diamond grid in the buffer layer maintains breathability under pressure; the rough surface of the lining layer enhances the wicking effect.

[0007] A further technical solution, the plant-derived cellulose aerogel is a three-dimensional network skeleton formed by high-pressure homogenization and defibrillation of bamboo fibers, and 3-aminopropyltriethoxysilane is grafted on the inner surface of the pores.

[0008] It should be noted that high-pressure homogenization fibrillates bamboo fibers into nanofibrils. The amino group of the silane coupling agent (such as 3-aminopropyltriethoxysilane) provides reaction sites, and the carboxyl group of the carboxylated silica shell (phase change microcapsule) serves as the coupling target. The amino group (-NH 2 ) of the silane coupling agent undergoes a condensation reaction with the carboxyl group (-COOH) of the phase change microcapsule shell to form an amide bond (-CONH-).

[0009] In a further technical solution, the organic phase change microcapsule has a core-shell structure, with the core being n-octadecane and the shell being carboxylated hollow mesoporous silica.

[0010] It should be noted that the mesoporous shell allows the volume expansion of the phase change material, and the amino group of the silane coupling agent and the carboxyl group of the microcapsule shell form an amide bond through a condensation reaction.

[0011] In a further technical solution, the carbon-based conductive material includes carbon fiber coated with graphene, which is axially gradient-distributed on the surface of the polyester fiber.

[0012] It should be noted that the gradient coverage avoids the breakage of the conductive network, and the high coverage rates at both ends enhance the electrode effect.

[0013] In a further technical solution, the superfine denier polyester matrix is a cross-shaped fiber with a nano-scale groove structure on the surface.

[0014] It should be noted that the groove structure increases the specific surface area and guides the directional filling of the aerogel through capillary action.

[0015] In a further technical solution, the sesame seed-shaped opening structure of the bonding layer includes main holes and auxiliary holes. The aperture of the main holes is 80 - 120 μm, the aperture of the auxiliary holes is 20 - 50 μm, and the number ratio of the main holes to the auxiliary holes is 1:3.

[0016] It should be noted that the main holes maintain the moisture permeability efficiency, and the auxiliary holes prevent the interlayer peeling caused by stress concentration.

[0017] In a further technical solution, PTFE nanofibers in the functional layer are radially interspersed in the TPU / PU matrix to form tortuous moisture-permeable channels.

[0018] It should be noted that the radial arrangement forms a labyrinth-like moisture-permeable path and at the same time blocks the penetration of liquid water.

[0019] In a further technical solution, breathable micropores with an aperture of 30 - 50 μm are provided at the nodes of the diamond-shaped grid of the buffer layer.

[0020] In a further technical solution, the inner layer of polyester Corte fabric is treated by plasma etching, and a multi-level rough structure is formed on the surface.

[0021] It should be noted that the multi-level rough structure accelerates the diffusion of sweat by increasing the specific surface area and the number of capillaries.

[0022] In a further technical solution, infrared reflection particles are evenly dispersed in the waterproof and moisture-permeable microporous membrane of the functional layer, and the infrared reflection particles are core-shell composites of titanium dioxide and zinc oxide.

[0023] It should be noted that after the surface layer carbon-based conductive material converts light energy into heat energy, the titanium dioxide / zinc oxide core-shell particles in the functional layer enhance the heat preservation in the following way: the titanium dioxide core reflects the long-wave infrared radiation of the human body, and the zinc oxide shell layer absorbs and scatters the medium-wave and short-wave infrared, forming a thermal radiation barrier, and the high-concentration gradient design on the surface layer preferentially reflects the cold radiation of the external environment.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: High heat storage and wash durability. Through the three-dimensional network skeleton of the plant-derived cellulose aerogel and the chemical bonding technology, the stable immobilization of the phase change microcapsules is realized. Compared with the traditional physical adsorption method, the present invention significantly improves the interfacial bonding strength, enabling the material to still maintain excellent heat storage performance after repeated washing, and solving the technical problems of easy shedding and rapid performance decay of traditional phase change materials.

[0025] Synergistic enhancement of moisture permeability and heat preservation. The unique moisture-permeable channel design and the gradient distribution of infrared reflection particles in the functional layer have breakthroughly balanced the moisture permeability and heat preservation performance. Compared with conventional waterproof and moisture-permeable membranes, the present invention can not only efficiently discharge moisture, but also effectively block the internal and external thermal radiation, realizing the dynamic thermal comfort regulation in a humid and hot environment.

[0026] Deformable design of the conductive network. The innovative gradient conductive network construction strategy endows the material with excellent flexibility and deformation adaptability. In dynamic use scenarios such as stretching and bending, the conductive performance is stable and reliable. At the same time, it cooperates with the photothermal conversion layer to significantly improve the energy utilization efficiency, overcoming the defects of traditional conductive fabrics being rigid and easily damaged.

[0027] Synergistic effect of the multi-level structure. The five-layer composite structure from the surface layer to the inner layer realizes functional coordination through bionic design: the open-hole design of the bonding layer enhances the interlayer bonding force, avoids blocking of the moisture-permeable channels, the grid structure of the buffer layer maintains the air permeability when compressed, improves the wearing comfort, and the micro-nano rough surface of the inner layer accelerates the sweat drainage, avoiding the feeling of dampness against the skin.

[0028] Through chemical bonding, gradient distribution, and bionic structure design, the present invention systematically addresses the technical bottlenecks of traditional phase change materials, such as the easy attenuation of heat storage performance, the difficulty in balancing moisture permeability and heat preservation, and the easy peeling of functional layers. Its multi-level synergistic effect provides an innovative solution for intelligent temperature-regulating clothing, which has high stability, wearing comfort, and environmental adaptability, significantly superior to existing single-functional or simple composite fabrics. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0030] The present invention will be further described below in conjunction with the drawings and embodiments.

[0031] Figure 1 It is a comparison chart of the test results of the phase change enthalpy of Examples 1-3 and Comparative Examples 1-4 in the present invention; Figure 2 It is a comparison chart of the test results of the moisture permeability of Examples 1-3 and Comparative Examples 1-4 in the present invention; Figure 3 It is a comparison chart of the test results of the conductivity of Examples 1-3 and Comparative Examples 1-4 in the present invention; Figure 4 It is a comparison chart of the test results of the infrared reflectivity of Examples 1-3 and Comparative Examples 1-4 in the present invention; Figure 5 It is a comparison chart of the test results of the wash retention rate of Examples 1-3 and Comparative Examples 1-4 in the present invention; Figure 6 It is an electron micrograph of the organic phase change microcapsules in the present invention; Figure 7 It is an electron micrograph of the three-dimensional network skeleton formed by the fibrillation of bamboo fibers after high-pressure homogenization in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following will further describe in detail the embodiments of the present invention in conjunction with the drawings and embodiments. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0033] In the description of the present invention, unless otherwise specified, "a plurality of" means two or more; the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the present invention. In addition, terms such as "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] I. The preparation process of the surface layer is as follows: Step 1: Preparation of plant-derived cellulose aerogel Raw material treatment: Bamboo fibers are treated with 5wt% NaOH solution at 80°C for 2h to remove lignin; High-pressure homogenization and defibrillation: The treated bamboo fibers are dispersed in deionized water (solid content 1wt%), and homogenized 10 times at 150MPa to obtain a nanofibril suspension; Freeze-drying: Pre-freeze at -50°C for 24h and vacuum freeze-dry for 48h to obtain a three-dimensional network aerogel; Silane coupling agent grafting: The aerogel is impregnated in a 3-aminopropyltriethoxysilane / ethanol solution (concentration 5wt%), reacted at 60°C for 6h, and washed and dried.

[0036] Step 2: Synthesis of organic phase change microcapsules Core preparation: n-Octadecane and Span80 emulsifier (mass ratio 95:5) are melted and mixed at 70°C, and ultrasonically emulsified (power 300W, 10min) to form an O / W emulsion; Shell coating: Tetraethyl orthosilicate (TEOS) and carboxylated silane coupling agent (molar ratio 3:1) are added to the emulsion, the pH is adjusted to 9, and hydrolysis and condensation are carried out at 60°C for 6h, followed by centrifugation and washing to obtain carboxylated silica shell microcapsules.

[0037] Step 3: Pretreatment of superfine polyester matrix Fiber modification: The cross-shaped ultrafine denier polyester (0.8D) is treated by plasma (power 100W, time 3min), and nano-grooves are formed on the surface; Coating with carbon-based conductive material: The graphene / carbon fiber dispersion liquid (graphene accounts for 30wt%) is gradient-coated by spraying process (the central spraying amount is 0.5mg / cm², and it increases to 1.2mg / cm² at both ends).

[0038] Step 4: The compounding process of the surface fabric is as follows: Mixed spinning: Mix aerogel (30 - 35 parts), microcapsules (20 - 25 parts), ultrafine denier polyester (40 - 50 parts) and carbon-based material (3 - 5 parts) according to the ratio, and melt-spin through a twin-screw extruder (temperature 250°C); Twisting of warp and weft: Adopt 2 / 2 twill weave, warp density 80 threads / cm, weft density 60 threads / cm, and the twisting number is 800 turns / m.

[0039] Example 1, components for preparing the surface layer: Mix aerogel (30 parts), organic phase change microcapsules (20 parts), ultrafine denier polyester (40 parts) and carbon-based material (3 parts) according to the ratio, and melt-spin through a twin-screw extruder.

[0040] Example 2, components for preparing the surface layer: Mix aerogel (33 parts), organic phase change microcapsules (23 parts), ultrafine denier polyester (45 parts) and carbon-based material (4 parts) according to the ratio, and melt-spin through a twin-screw extruder.

[0041] Example 3, components for preparing the surface layer: Mix aerogel (35 parts), organic phase change microcapsules (25 parts), ultrafine denier polyester (50 parts) and carbon-based material (5 parts) according to the ratio, and melt-spin through a twin-screw extruder.

[0042] Comparative example 1: Components for preparing the surface layer: Mix aerogel (28 parts), organic phase change microcapsules (20 parts), ultrafine denier polyester (40 parts) and carbon-based material (3 parts) according to the ratio, and melt-spin through a twin-screw extruder.

[0043] Comparative example 2: Components for preparing the surface layer: Mix aerogel (30 parts), organic phase change microcapsules (18 parts), ultrafine denier polyester (40 parts) and carbon-based material (3 parts) according to the ratio, and melt-spin through a twin-screw extruder.

[0044] Comparative example 3: Components for preparing the surface layer: Mix aerogel (30 parts), organic phase change microcapsules (20 parts), superfine denier polyester (55 parts) and carbon-based material (3 parts) according to the ratio, and melt-spin them through a twin-screw extruder.

[0045] Comparative Example 4: Components for preparing the surface layer: Mix aerogel (30 parts), organic phase change microcapsules (20 parts), superfine denier polyester (40 parts) and carbon-based material (6 parts) according to the ratio, and melt-spin them through a twin-screw extruder.

[0046] Second, the preparation process of the bonding layer is as follows: Material: Thermoplastic polyurethane (TPU, melt index 15 g / 10 min); Open-cell forming: Press the TPU melt through a template (temperature 180 °C). The template is designed with main holes (Φ100 μm) and auxiliary holes (Φ35 μm), and the hole density of the main:auxiliary = 1:3; Laminating and compounding: Bond the surface layer and the functional layer by hot pressing (pressure 0.5 MPa, temperature 160 °C, time 30 s).

[0047] Third, the preparation process of the functional layer is as follows: Matrix mixing: Blend TPU / PU (mass ratio 7:3) with PTFE nanofibers (10 wt%); Radial arrangement: Make the PTFE fibers radially distributed by electrospinning (voltage 25 kV, receiving distance 15 cm); Infrared particle dispersion: Incorporate titanium dioxide / zinc oxide core-shell particles (particle size 80 nm, shell thickness 15 nm) into the film layer according to the gradient concentration (7 wt% on the surface layer, 4 wt% on the bottom layer); Microporous forming: Use the phase separation method (the coagulation bath is water / ethanol = 1:1) to form moisture-permeable channels with pore diameters of 0.1 - 0.3 μm.

[0048] Fourth, the preparation process of the buffer layer is as follows: Rhombic grid forming: The breathable polyurethane (breathability 8000 g / (m²·24 h)) is laser engraved to form a rhombic grid (side length 2 mm, line width 0.2 mm); Micropore machining: Laser drill holes (hole diameter 40 μm, density 50 holes / cm²) at the grid nodes.

[0049] Fifth, the preparation process of the inner layer is as follows: Fabric treatment: The polyester Corte fabric (grammage 150 g / m²) is etched by argon plasma (power 150 W, time 5 min) to form first-level pits (depth 1.5 μm, Φ4 μm) and second-level protrusions (height 300 nm, spacing 80 nm); Tear resistance treatment: Impregnated with a polyurethane coating (solid content 10%), the tear strength is increased to 45 N after drying (GB / T3917.3).

[0050] Data comparison of Examples 1-3 and Comparative Examples 1-4 of the surface layer: Performance test standards Performance test results: Data analysis: 1. Verification of optimized component ratio Phase change enthalpy: In Examples 1-3, it is all > 175 J / g, while in Comparative Examples 1-3, due to the imbalance of component ratios, the phase change enthalpy decreased significantly (↓10%-18%), proving that 30-35 parts of aerogel and 20-25 parts of microcapsules in the claims are the optimal ranges.

[0051] Water vapor transmission rate: In Comparative Example 3 (excessive ultrafine polyester fiber matrix), the water vapor transmission rate dropped sharply by 32%, indicating that 40-50 parts of the ultrafine polyester fiber matrix can balance the structural strength and porosity.

[0052] 2. Synergistic effect of the functional layer Infrared reflectance: In Examples 1-3, it is all > 85%, due to the bidirectional thermal radiation barrier (human body + environment) achieved by the gradient-distributed core-shell particles.

[0053] Conductivity: In Comparative Example 4 (excessive carbon-based material), although the conductivity is high, the water vapor transmission rate and wash resistance deteriorate, verifying that 3-5 parts is the critical value for balancing photothermal conversion and water vapor transmission.

[0054] 3. Key factors for durability Wash resistance: The wash retention rate of Examples 1-3 is > 90%, significantly higher than that of the comparative examples (76-88%), mainly due to: chemical bonding (amide bond) preventing the microcapsules from falling off, and the gradient conductive network avoiding stress concentration and fracture.

[0055] The embodiments of the present invention are given for purposes of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are chosen and described in order to better explain the principles of the invention and its practical application, and to enable those of ordinary skill in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A composite phase change fiber fabric, characterized in that: It consists of five layers stacked in sequence. The surface layer is a warp-weft twisted surface fabric formed by a composite of plant-derived cellulose aerogel, organic phase-change microcapsules, ultrafine denier polyester matrix and carbon-based conductive materials, wherein the raw materials are mixed in the following weight ratios: 30-35 parts of plant-derived cellulose aerogel, 20-25 parts of organic phase-change microcapsules, 40-50 parts of ultrafine denier polyester matrix and 3-5 parts of carbon-based conductive materials; A bonding layer, a thermoplastic polyurethane adhesive layer having a sesame-dot open-pore structure, wherein the open pores penetrate the surface layer and the functional layer; Functional layer, including waterproof and breathable microporous membrane of TPU, PU and PTFE; Buffer layer, a vapor-permeable polyurethane layer with a diamond grid structure; Lining: moisture-wicking, quick-drying, tear-resistant polyester cot fabric.

2. A composite phase change fiber fabric according to claim 1, characterized in that: The plant-derived cellulose aerogel is a three-dimensional network skeleton formed by high-pressure homogenization and defibration of bamboo fibers, and 3-aminopropyltriethoxysilane is grafted onto the inner surface of the pores.

3. The composite phase change fiber fabric according to claim 1, characterized in that: The organic phase-change microcapsule is a core-shell structure, wherein the core is n-octadecane and the shell is carboxylated hollow mesoporous silica.

4. The composite phase change fiber fabric according to claim 1, characterized in that: The carbon-based conductive material comprises carbon fibers coated with graphene and is distributed in an axial gradient on the surface of the polyester fibers.

5. The composite phase change fiber fabric according to claim 1, characterized in that: The ultra-fine denier polyester matrix is ​​a cross-shaped cross-section fiber with a nano-scale groove structure on the surface.

6. The composite phase change fiber fabric according to claim 1, characterized in that: The sesame-dot opening structure of the bonding layer includes main holes and auxiliary holes. The main holes have a diameter of 80-120 μm, the auxiliary holes have a diameter of 20-50 μm, and the ratio of the main holes to the auxiliary holes is 1:

3.

7. The composite phase change fiber fabric according to claim 1, characterized in that: The PTFE nanofibers in the functional layer are radially interspersed in the TPU / PU matrix to form a tortuous moisture permeable channel.

8. The composite phase change fiber fabric according to claim 1, characterized in that: The diamond grid nodes of the buffer layer are provided with air-permeable micropores, and the pore diameter is 30-50 μm.

9. The composite phase change fiber fabric according to claim 1, characterized in that: The inner layer of polyester cot fabric is treated by plasma etching to form a multi-level rough structure on the surface.

10. The composite phase change fiber fabric according to claim 1, characterized in that: Infrared reflective particles are evenly dispersed in the waterproof and breathable microporous film of the functional layer. The infrared reflective particles are core-shell composites of titanium dioxide and zinc oxide.

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