阅读说明：本技术 一种保温与散热双功能热管理织物及其制备方法 (Heat-preservation and heat-dissipation dual-function heat management fabric and preparation method thereof ) 是由 李强 罗皓 朱屹凝 仇旻 于 2021-07-07 设计创作，主要内容包括：本发明提供一种保温与散热双功能热管理织物及其制备方法。其中,热管理织物包括：纤维织物、设于纤维织物一侧的金属纳米颗粒层以及设于纤维织物另一侧的多孔聚合物涂层。制备方法包括在纤维织物的两侧分别沉积金属纳米颗粒层和多孔聚合物涂层,即得双功能热管理织物。本发明在传统布料一面引入金属纳米颗粒,利用局域表面等离激元谐振实现对热辐射的抑制与太阳光的高效吸收,即保温性能。并在传统布料另一面涂覆多孔聚合物膜,利用其内部空气孔实现对太阳光的高效散射,利用其自身在中红外的高辐射特性进行辐射散热。该保温功能和散热功能也可以单独使用。保温与散热双功能个人热管理织物还可结合转轴等机械结构应用在建筑物与车辆节能等领域。(The invention provides a thermal management fabric with heat preservation and heat dissipation functions and a preparation method thereof. Wherein the thermal management fabric comprises: the metal nanoparticle composite comprises a fiber fabric, a metal nanoparticle layer arranged on one side of the fiber fabric and a porous polymer coating arranged on the other side of the fiber fabric. The preparation method comprises the step of respectively depositing a metal nanoparticle layer and a porous polymer coating on two sides of the fiber fabric to obtain the bifunctional heat management fabric. According to the invention, metal nanoparticles are introduced into one surface of the traditional cloth, and the inhibition of thermal radiation and the efficient absorption of sunlight, namely the heat preservation performance, are realized by utilizing the local surface plasmon resonance. And the other side of the traditional cloth is coated with a porous polymer film, the internal air holes of the porous polymer film are utilized to realize the high-efficiency scattering of sunlight, and the high radiation characteristic of the porous polymer film in the middle infrared is utilized to radiate and dissipate heat. The heat preservation function and the heat dissipation function can be independently used. The heat preservation and heat dissipation double-function personal heat management fabric can be applied to the fields of energy conservation of buildings and vehicles and the like by combining with mechanical structures such as rotating shafts and the like.)

1. A thermal management fabric with heat preservation and heat dissipation functions is characterized by comprising:

the metal nanoparticle composite material comprises a fiber fabric, a metal nanoparticle layer arranged on one side of the fiber fabric and a porous polymer coating arranged on the other side of the fiber fabric.

2. The thermal management fabric with the functions of heat preservation and heat dissipation as claimed in claim 1, wherein the fiber fabric is one or more of polyester fibers, polyamide fibers, polyurethane fibers, polyvinyl acetal fibers, polypropylene fibers, acetate fibers, cotton and silk.

3. The heat-preservation and heat-dissipation bifunctional heat management fabric as claimed in claim 1, wherein the mid-infrared thermal emissivity of the metal nanoparticle layer is 0-0.5; the sunlight absorption rate is 0.4-1.

4. The thermal management fabric with the functions of heat preservation and heat dissipation according to claim 1, wherein the metal nanoparticle layer is made of zinc, titanium, copper, aluminum, silver or gold.

5. The heat-preservation and heat-dissipation bifunctional heat management fabric as claimed in claim 1, wherein the thickness of the metal nanoparticle layer is 50-1000 nm.

6. The heat-preservation and heat-dissipation dual-function heat management fabric as claimed in claim 1, wherein the mid-infrared emissivity of the porous polymer coating is 0.5-1; the solar reflectance is 0.4-1.

7. The thermal management fabric with dual functions of heat preservation and heat dissipation according to claim 1, wherein the porous polymer coating is polymethyl methacrylate, polydimethylsiloxane or polyvinylidene fluoride.

8. The thermal management fabric with the functions of heat preservation and heat dissipation according to claim 1, wherein the thickness of the porous polymer coating is 5-500 μm.

9. The thermal management fabric with dual functions of heat preservation and heat dissipation according to claim 1, wherein the thermal management fabric achieves different thermal functions by turning over an application surface.

10. The preparation method of the heat-preservation and heat-dissipation bifunctional heat management fabric as claimed in any one of claims 1 to 9, characterized by comprising the step of respectively depositing a metal nanoparticle layer and a porous polymer coating on two sides of a fiber fabric to obtain the bifunctional heat management fabric.

Technical Field

The invention belongs to the technical field of thermal management fabric design, and particularly relates to a thermal management fabric with heat preservation and heat dissipation double functions and a preparation method thereof.

Background

Human heat dissipation includes conduction, convection, evaporation, and radiation heat dissipation, which accounts for about 65% of human heat dissipation at an ambient temperature of 26 ℃. The traditional fabric mainly realizes the inhibition of conduction/convection heat dissipation by changing the geometric thickness of materials (such as cotton coats and down coats), and can only realize a single heat preservation/heat dissipation function under a specific thickness.

Research on personal radiation heat management has been proposed by the united states space agency in about 60 th of the 20 th century, and the result is a space suit structure based on polyethylene terephthalate with aluminum deposited thereon, but since the polyethylene terephthalate adopted by the space suit is dense and non-porous, the structure has extremely poor air and water vapor permeability and can only realize heat preservation.

In subsequent researches, Stanford university realizes heat preservation/heat dissipation double-function personal heat management fabric based on a complex porous nanostructure, and the fabric realizes double-function indoor personal heat management in a mode of compounding a nano-porous polyethylene film, a copper plating layer, a carbon coating and the compound nano-porous polyethylene film. The heat preservation function is realized by reflecting human body infrared heat radiation through the copper coating, the heat dissipation function is realized by carbon paste with high radiance, and the sunlight absorption rate of two surfaces of the fabric cannot be regulated and controlled due to the fact that the fabric is composed of the nano-pore polyethylene film inside and outside, and the fabric is only suitable for indoor heat management.

The traditional personal heat management method focuses on changing the heat conduction performance of materials, but the control of heat radiation and heat dissipation is lacked, and the recent research on the human body radiation heat management only adjusts and controls the radiation characteristics of the materials, so that the traditional personal heat management method is difficult to be applied to outdoor open environments.

In subsequent studies, researchers have implemented bifunctional personal thermal management fabrics that preserve/dissipate heat based on complex porous nanostructures, consisting essentially of five layers of material (document 1: https:// pubs. acs. org/doi/abs/10.1021/acs. nanolett.1c00400): the composite material comprises a polymethyl methacrylate coating used for radiation heat dissipation, a polytetrafluoroethylene microporous membrane and an aluminum nano-pore structure, a nano-pore polyethylene film used for radiation heat preservation and copper-zinc mixed nanoparticles deposited on battery diaphragm nano-pore polyethylene. This solution has the following drawbacks: 1. polytetrafluoroethylene and polyethylene are used as substrate materials, so that the tearing resistance and wearability of the fabric are weak; 2. the use of a polyethylene base material has poor air permeability. 3. Three metal structures of copper, zinc and aluminum are needed, so that the process complexity is increased; 4 the heat-insulating layer and the heat-radiating layer are required to be combined by means of sewing or cold/hot pressing and the like, so that the heat-insulating layer and the heat-radiating layer have the problems of easy peeling, fragility and the like.

Disclosure of Invention

Aiming at the defects and shortcomings of the prior art, the invention provides a personal heat management fabric which can realize switchable heat preservation and heat dissipation double functions, has low biological toxicity and excellent wearing performance and is based on a structure formed by metal and a preparation method thereof based on an asymmetric micro-nano optical structure.

A thermal management fabric with thermal insulation and heat dissipation functions, comprising:

the metal nanoparticle composite material comprises a fiber fabric, a metal nanoparticle layer arranged on one side of the fiber fabric and a porous polymer coating arranged on the other side of the fiber fabric.

In the above technical scheme, the fiber fabric is used as the substrate layer, and chemical fibers or natural fibers can be selected. The metal nanoparticle layer serves as an insulating layer to provide a heat preservation mode for the heat management fabric, and the porous polymer coating serves as a heat dissipation layer to provide a heat dissipation mode for the heat management fabric. The thermal management fabric can be used independently in both the heat preservation mode and the heat dissipation mode.

The thermal management fabric of the present invention has excellent wear properties, including tear resistance and air permeability, which are equivalent to common chemical and natural fibers.

Preferably, the fiber fabric is one or more of common chemical fibers such as polyester fibers (dacron), polyamide fibers (nylon), polyurethane fibers (spandex), polyvinyl acetal fibers (vinylon), polypropylene fibers (polypropylene fibers) and acetate fibers, and natural fibers such as cotton and silk. The terylene cloth (polyester fiber) as a mature material has good heat resistance, high safety and excellent wearability in the deposition process.

Preferably, the mid-infrared emissivity of the metal nano particle layer is 0-0.5; the sunlight absorption rate is 0.4-1.

Preferably, the metal material used for the metal nanoparticle layer is zinc, titanium, copper, aluminum, silver or gold.

Preferably, the thickness of the metal nanoparticle layer is 50 to 1000 nm.

More preferably, the thickness of the metal nanoparticle layer is 300 to 900 nm.

Preferably, the metal nanoparticle layer is composed of a plurality of different sizes of metal nanoparticles randomly distributed to form the metal nanoparticle layer;

the size range of the metal nanoparticles is 10-800 nm.

In the technical scheme, the metal nanoparticles support local surface plasmon resonance, the resonance wavelengths supported by the metal nanoparticles with different sizes are different, and the absorption of a broad spectrum is realized by adopting the metal nanoparticles with different sizes; for the middle infrared thermal radiation wave band, the dense metal nano particles can be similar to a layer of metal film, and the effect of efficiently reflecting thermal radiation can be achieved.

Preferably, the intermediate infrared emissivity of the porous polymer coating is 0.5-1; the solar reflectance is 0.4-1.

Preferably, the porous polymer coating is polymethylmethacrylate, polydimethylsiloxane or polyvinylidene fluoride.

Preferably, the thickness of the porous polymer coating is 5 to 500 μm.

More preferably, the thickness of the porous polymer coating is 10 to 100 μm.

Preferably, the porous polymeric coating has a plurality of air pores of different sizes, the plurality of air pores of different sizes being randomly distributed within the porous polymeric coating;

the size range of the air holes is 100-3000 nm.

In the technical scheme, the porous polymer contains air holes with different sizes, the air holes have efficient backscattering effect on sunlight with specific wavelength, and the air holes with different sizes can realize wide-spectrum reflection; for the middle infrared thermal radiation wave band, the porous polymer coating and the fiber fabric used as the substrate have high thermal radiation rate, and high-efficiency radiation heat dissipation can be realized.

The principle of the thermal insulation of the thermal management fabric of the invention is as follows: in the wave band of a solar spectrum (comprising visible light and near infrared light), the high-efficiency absorption of sunlight is realized by utilizing the metal nano structure; in the middle infrared thermal radiation wave band, the high reflection of the metal nano structure to the thermal radiation reflects the thermal radiation of the human body back to the human body, so that the heat preservation is realized.

The principle of its heat dissipation lies in: in the solar spectrum (including visible light and near infrared light) wave band, the porous polymer coating is utilized to realize high-efficiency reflection of sunlight; in the middle infrared thermal radiation wave band, based on the high thermal emissivity characteristic of the polymer coating, the radiation heat dissipation is realized.

Preferably, the thermal management fabric performs different thermal functions by flipping the application side.

As shown in fig. 1, the factors affecting the thermal management of outdoor individuals mainly include three points: (1) the outdoor human body radiation loss is higher, the outdoor personal radiation heat dissipation rate is 4 times of the indoor radiation heat dissipation rate, and the outdoor heat preservation difficulty is higher than that of the indoor heat preservation difficulty; (2) outdoor sun is a black body radiation source at 5500 ℃, and the radiation difficulty can be obviously improved by the absorption of the fabric on sunlight; (3) the outdoor temperature has a wider variation range, and personal thermal management cannot be regulated and controlled by means of air conditioners and the like.

The regulation of the outdoor heat preservation/dissipation performance of the fabric requires the coordinated regulation of the solar spectrum band characteristic and the mid-infrared thermal radiation band characteristic, and the realization of the two functions based on a single fabric means that the two sides of the fabric bear two distinct functions. The difunctional material of design realizes two kinds of different hot functions through the upset in this patent, and white cooling surface is towards the outside under the heat dissipation mode, and black heat preservation surface is towards the outside under the heat preservation mode.

The bifunctional heat management fabric of the present invention can be used in combination with different thermal conductivity materials (such as aerogel, graphite, etc.) for enhancing the thermal insulation or heat dissipation efficiency thereof.

The dual-function heat management fabric can be worn by individuals and can also be applied to the field of energy conservation of buildings and vehicles.

The preparation method of the heat-preservation and heat-dissipation bifunctional heat management fabric comprises the step of respectively depositing the metal nanoparticle layer and the porous polymer coating on two sides of the fiber fabric to obtain the bifunctional heat management fabric.

In the above technical solution, the fiber fabric may be one layer or two layers.

The metal nanoparticles take zinc nanoparticles as an example, and the preparation method of the heat-preservation and heat-dissipation bifunctional heat management fabric comprises the following steps:

when the fiber fabric is a layer, as shown in fig. 2(a), based on the fiber fabric as a substrate, zinc nanoparticles are deposited on one side of the fiber fabric by means of magnetron sputtering or evaporation or chemical plating or electroplating, and a porous polymer coating is deposited on the other side of the fiber fabric by means of phase separation spraying or blade coating, so as to obtain the bifunctional thermal management fabric.

When the fiber fabric is two layers, as shown in fig. 2(b), the zinc nanoparticles and the porous polymer coating are respectively deposited on one side of two pieces of fiber fabric, and the other side of the two pieces of fiber fabric is opposite and compounded by means of sewing or hot pressing to form the bifunctional heat management fabric.

In the technical scheme, when the porous polymer is sprayed and deposited on the surface of the fiber fabric to form the porous polymer coating, the porous polymer material capable of forming a film by a phase separation method is prepared into spraying liquid, and then spraying is carried out. Wherein the spraying liquid is a mixed solution of a porous polymer material, acetone and deionized water (the mass ratio of the porous polymer material to the acetone to the deionized water is 1: 8: 1).

In the spraying process, a spray pen (the air pressure range is 100-200 kPa) is adopted to evenly coat the spraying liquid on cotton cloth, and then the cotton cloth is naturally dried in a normal-temperature fume hood.

According to the invention, metal nanoparticles are introduced into one surface of the traditional cloth, and the inhibition of thermal radiation and the efficient absorption of sunlight, namely the heat preservation performance, are realized by utilizing the local surface plasmon resonance. According to the invention, the other side of the traditional cloth is coated with the porous polymer film, the internal air holes of the porous polymer film are utilized to realize efficient scattering of sunlight, and the high radiation characteristic of the porous polymer film in the middle infrared is utilized to radiate and dissipate heat. The heat preservation function and the heat dissipation function can be independently used. The heat preservation/heat dissipation double-function personal heat management fabric can be applied to the fields of energy conservation of buildings and vehicles and the like by combining with mechanical structures such as rotating shafts and the like.

Compared with the prior art, the invention has the beneficial effects that:

(1) aiming at personal heat management, the optical characteristics of the micro-nano optical material in a sunlight wave band and an infrared radiation wave band are cooperatively regulated and controlled by optimizing the micro-nano optical material and the structure, so that the personal heat management fabric with heat preservation and heat dissipation functions, strong mechanical property (tearing resistance) and air permeability and low heavy metal content is realized.

(2) The radiation heat management is combined with solar heat collection and radiation scattering, so that passive and passive environment-friendly heat management is realized.

(3) The heat dissipation mode and the heat preservation mode can be used independently and the performance is stronger than that of the traditional fabric with similar thickness.

Drawings

FIG. 1 is a schematic diagram of a thermal insulation and heat dissipation dual-function personal thermal management fabric of the present invention;

in fig. 2: (a) a flow chart for preparing a thermal management fabric for a single layer fabric; (b) a flow chart for preparing a thermal management fabric for a double-layer fiber fabric;

FIG. 3 is a scanning electron microscope image of the thermal management fabric with heat preservation and heat dissipation functions in the embodiment;

FIG. 4 is an optical imaging and a thermal imaging of the thermal insulating and heat dissipating dual-function personal thermal management fabric of the embodiment;

FIG. 5 is a solar band reflectivity spectrum and mid-infrared radiance spectrum of the thermal insulation and heat dissipation dual-function personal thermal management fabric in an embodiment;

FIG. 6 shows the result of the tear resistance test of the thermal management fabric with heat preservation and dissipation functions in the embodiment;

FIG. 7 shows the water vapor permeability performance test results of the thermal insulation and heat dissipation dual-function personal thermal management fabric in the embodiment.

Detailed Description

Taking a layer of cotton cloth, and depositing zinc nanoparticles on the layer of cotton cloth in a magnetron sputtering mode (equipment is Denton Discovery 635, the power is 90 watts, and the deposition time is 600 seconds), wherein the deposition thickness is about 700 nanometers, and the size range of the zinc nanoparticles is 10 nanometers-800 nanometers; another layer of cotton cloth is taken, and the porous polymethyl methacrylate is coated on the layer of cotton cloth in a spraying mode. Before spraying, the polymer material porous polymethyl methacrylate which can be formed into a film by a phase separation method is firstly prepared into spraying liquid, and then spraying is carried out. Wherein the spraying liquid is a mixed solution of polymethyl methacrylate, acetone and deionized water (the mass ratio is 1: 8: 1), a spray pen (the air pressure is 150kPa) is adopted to uniformly coat the spraying liquid on cotton cloth in the spraying process, then the cotton cloth is naturally dried in a normal-temperature fume hood, the coating thickness is about 20 micrometers, and the size range of air holes in the porous polymethyl methacrylate is 100-3000 nanometers; and (3) enabling the two layers of cotton cloth to be opposite to each other at the side where no substance is deposited, and compounding the two layers of cotton cloth and the side where no substance is deposited in a hot pressing mode to form the heat-preservation and heat-dissipation bifunctional heat management fabric.

A scanning electron microscope image of the thermal management fabric prepared above is shown in fig. 3. As can be seen from fig. 3, the thermal insulation surface is mainly composed of zinc nanoparticles, and the size distribution range is large, so that the wide-spectrum absorption of sunlight can be realized. The heat dissipation surface is composed of a polymethyl methacrylate coating rich in micropores, the size distribution range of air holes is large, and the wide-spectrum scattering of sunlight can be realized.

As shown in fig. 4, in the optical imaging, the heat preservation surface of the heat management fabric with the heat preservation and dissipation double functions is dark gray, which corresponds to high sunlight absorption rate; the heat dissipation surface is bright white and corresponds to the characteristic of high solar reflectance. In thermal imaging, the heat preservation surface is in a cold color and is correspondingly subjected to high-radiation heat preservation; the radiating surface is warm and corresponds to the high radiation radiating characteristic.

The spectral characteristics of the heat-preservation and heat-dissipation bifunctional heat management fabric are shown in fig. 5, and the heat management fabric has low thermal radiance, low solar reflectivity and high solar absorptivity in a heat preservation mode; the heat management fabric has high thermal radiance, high solar reflectivity and low solar absorptivity in a heat dissipation mode.

Tear resistance test

The thermal management fabric with the heat preservation function and the heat dissipation function and the thermal management fabric provided in the document 1 are subjected to a tearing resistance test (the device model is Q800, and the tearing speed is 100 mm/s), and the result is shown in fig. 6.

As can be seen from fig. 6, the maximum load (without significant tearing and film peeling) of the thermal management fabric of this embodiment (shown in the figure) is 500 n, while the maximum load of the bifunctional fabric provided in document 1(https:// pubs. acs. org/doi/abs/10.1021/acs. nanolett.1c00400) is only less than 50 n, and the mechanical strength (tear resistance) of the bifunctional thermal management fabric in this embodiment is much stronger than that of the fabric provided in document 1, and has excellent tear resistance.

Water vapor permeability test

The test is referred to american society for testing and materials ASTM E96, test method as follows: different fabrics (heat management fabric of the embodiment of the present invention, cotton cloth, and heat management fabric provided in document 1) were used to cover a plastic petri dish (diameter 55 mm) containing a certain amount of water, and after 6 hours, the plastic petri dish was placed in a constant temperature and humidity chamber at 27 degrees centigrade and 10% humidity, and weight loss was obtained by weight measurement. The weight loss is the weight of evaporated water vapor and is used for characterizing the water vapor permeability of the fabric, and the test result is shown in fig. 7.

As can be seen from fig. 7, the water vapor permeability of the thermal management fabric with heat preservation and heat dissipation functions (shown in the figure as the invention) of this embodiment is closer to that of cotton cloth, and is improved compared with document 1, which shows that the thermal management fabric prepared in this embodiment has better water vapor permeability.