CN111690301A - Radiation refrigeration coating with gradient structure and preparation method and application thereof - Google Patents

Radiation refrigeration coating with gradient structure and preparation method and application thereof Download PDF

Info

Publication number
CN111690301A
CN111690301A CN202010484757.8A CN202010484757A CN111690301A CN 111690301 A CN111690301 A CN 111690301A CN 202010484757 A CN202010484757 A CN 202010484757A CN 111690301 A CN111690301 A CN 111690301A
Authority
CN
China
Prior art keywords
coating
inorganic powder
radiation
polymer binder
solvent
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202010484757.8A
Other languages
Chinese (zh)
Other versions
CN111690301B (en
Inventor
周军
段将将
胡彬
刘沛
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huazhong University of Science and Technology
Original Assignee
Huazhong University of Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huazhong University of Science and Technology filed Critical Huazhong University of Science and Technology
Priority to CN202010484757.8A priority Critical patent/CN111690301B/en
Publication of CN111690301A publication Critical patent/CN111690301A/en
Application granted granted Critical
Publication of CN111690301B publication Critical patent/CN111690301B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D129/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Coating compositions based on hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Coating compositions based on derivatives of such polymers
    • C09D129/14—Homopolymers or copolymers of acetals or ketals obtained by polymerisation of unsaturated acetals or ketals or by after-treatment of polymers of unsaturated alcohols
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
    • B05D7/24—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D101/00—Coating compositions based on cellulose, modified cellulose, or cellulose derivatives
    • C09D101/08—Cellulose derivatives
    • C09D101/26—Cellulose ethers
    • C09D101/28—Alkyl ethers
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D127/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers
    • C09D127/02—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment
    • C09D127/12—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Coating compositions based on derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
    • C09D127/18—Homopolymers or copolymers of tetrafluoroethene
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D133/00—Coating compositions based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Coating compositions based on derivatives of such polymers
    • C09D133/04—Homopolymers or copolymers of esters
    • C09D133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/004—Reflecting paints; Signal paints
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/66—Additives characterised by particle size
    • C09D7/67—Particle size smaller than 100 nm
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/66—Additives characterised by particle size
    • C09D7/68—Particle size between 100-1000 nm
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40—Additives
    • C09D7/66—Additives characterised by particle size
    • C09D7/69—Particle size larger than 1000 nm
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2237—Oxides; Hydroxides of metals of titanium
    • C08K2003/2241—Titanium dioxide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/24—Acids; Salts thereof
    • C08K3/26—Carbonates; Bicarbonates
    • C08K2003/265—Calcium, strontium or barium carbonate
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/30—Sulfur-, selenium- or tellurium-containing compounds
    • C08K2003/3045—Sulfates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/002—Physical properties
    • C08K2201/003—Additives being defined by their diameter
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00—Specific properties of additives
    • C08K2201/011—Nanostructured additives

Abstract

The invention discloses a radiation refrigeration coating with a gradient structure and a preparation method and application thereof, belonging to the field of new materials. The invention provides a radiation refrigeration coating with a gradient structure, which comprises a polymer binder and inorganic powder, wherein the emissivity of the polymer binder in a middle infrared band is higher than 0.85, the reflectivity of the inorganic powder in a solar spectrum band is higher than 0.85, the content of the polymer binder is gradually reduced and the content of the inorganic powder is gradually increased in a direction away from a radiation surface. Therefore, a large amount of polymer adhesive is arranged above the coating, inorganic powder is arranged below the coating, and the polymer adhesive is used for emitting the mid-infrared spectrum, and the inorganic powder is mainly used for reflecting the solar spectrum, so that a good refrigeration effect can be ensured. Meanwhile, the coating with the polymer binder and the inorganic powder integrated can prevent the problems of peeling, delamination and the like caused by the lamination of two layers of materials, and realize the effect of balanced transition on the structure and further stable structure.

Description

Radiation refrigeration coating with gradient structure and preparation method and application thereof
Technical Field
The invention relates to the field of new materials, in particular to a radiation refrigeration coating with a gradient structure and a preparation method thereof.
Background
Under the large background of global warming, the cooling energy consumption of buildings accounts for 20% -50% of the global energy consumption. The traditional building refrigeration mainly adopts an active refrigeration technology of compression work heat cycle (namely air conditioning). This refrigeration technology consumes a large amount of electric energy, aggravates global warming and energy crisis, and forms a vicious circle.
The radiation refrigeration is a radiation refrigeration technology with zero energy consumption, and means that a heat source exchanges heat with an outer space cold source (3K) through an infrared window in the atmosphere in a heat radiation mode. Most of materials have better heat radiation capability, but also absorb sunlight, and the heat load after the photothermal conversion is usually higher than the heat radiation power, so that the daytime cooling effect is difficult to realize. The molecular skeleton of the high molecular material contains abundant vibration modes, and is an excellent mid-infrared thermal emitter. The white inorganic powder with high refractive index generally has low sunlight absorptivity and is an excellent sunlight reflector. In some coating/film materials with the radiation refrigeration function, the coating/film material is prepared by compounding a high polymer material and white inorganic powder so as to realize the effect of cooling in daytime.
The compounding method of the polymer material and the white inorganic powder generally includes two forms: firstly, uniformly blending the two; second, both the polymer material and the inorganic powder are laminated. The first blended coating/film material is of a uniform structure, has both sunlight reflection and mid-infrared emission performances, but cannot give full play to the respective advantages of high polymers and inorganic powder, and is a compromise in performance. Although the second laminated heterostructure can achieve the optimal radiation refrigeration effect theoretically, the problems of severe thermal expansion and mechanical mismatch exist between the upper layer and the lower layer of the material, the problems of peeling, delamination and the like exist in the long-term use process of the material, and the great hidden danger exists in the stability of the material. In addition, the laminated structure material needs to be formed for many times, and the preparation process is complicated.
Disclosure of Invention
In order to solve the problems of how to adopt a simple preparation process, realize the optimized radiation refrigeration performance of a polymer and inorganic powder composite material and meet excellent structural stability, the embodiment of the invention provides a radiation refrigeration coating with a gradient structure and a preparation method thereof. The technical scheme is as follows:
in one aspect, the invention provides a radiation refrigeration coating with a gradient structure, the coating comprises a polymer binder and inorganic powder, the polymer binder has an emissivity higher than 0.85 in a middle infrared band, the inorganic powder has a reflectivity higher than 0.85 in a solar spectrum band, the content of the polymer binder is gradually reduced and the content of the inorganic powder is gradually increased in a direction away from a radiation surface.
Further, in the direction far away from the radiation surface, the volume ratio of the polymer binder to the inorganic powder is gradually changed from X:1 to 1: X, wherein X is between 2 and 100, and X is between 2 and 100.
Further, the thickness of the coating is 0.1-1 mm.
Furthermore, the particle size of the inorganic powder is between 0.02 and 2 mu m.
Further, the inorganic powder comprises BaSO4、TiO2、Al2O3、SiO2、CaSO4、MgO、CaCO3One or two of them.
The invention also provides application of any one of the radiation refrigeration coatings, wherein the radiation refrigeration coating comprises the radiation surface and an attachment surface opposite to the radiation surface, the attachment surface is used for attaching to a substrate, and the substrate comprises one or more of metal, ceramic, plastic, composite materials, fixed parts and moving parts.
In another aspect, the present invention provides a method for preparing a radiation refrigeration coating having a gradient structure, the method comprising:
uniformly dispersing a polymer binder and inorganic powder in a solvent to obtain a suspension, wherein the emissivity of the polymer binder in a middle infrared band is higher than 0.85, and the reflectivity of the inorganic powder in a solar spectrum band is higher than 0.85;
spraying or blade coating the suspension on a substrate;
the solvent is slowly volatilized, so that the mass ratio of the polymer binder to the inorganic powder presents gradient distribution in the direction vertical to the thickness of the coating.
Further, the volume fraction of the solvent in the suspension is 50-90%, the solvent is a mixture of water and an organic solvent, and the volume ratio of the water in the mixture is 10-90%.
Further, the specific method for slow volatilization of the solvent is as follows: the volatilization time is not less than 1 hour at the temperature of 20-40 ℃.
Further, the organic solvent is one or two of ethanol, toluene and acetone.
The technical scheme provided by the embodiment of the invention has the beneficial effects that at least:
the invention provides a radiation refrigeration coating with a gradient structure, which comprises a polymer binder and inorganic powder, wherein the emissivity of the polymer binder in a middle infrared band is higher than 0.85, the reflectivity of the inorganic powder in a solar spectrum band is higher than 0.85, the content of the polymer binder is gradually reduced and the content of the inorganic powder is gradually increased in a direction away from a radiation surface. Therefore, a large amount of polymer adhesive is arranged above the coating, inorganic powder is arranged below the coating, and the polymer adhesive is used for emitting the mid-infrared spectrum, and the inorganic powder is mainly used for reflecting the solar spectrum, so that a good refrigeration effect can be ensured. Meanwhile, the coating with the polymer binder and the inorganic powder integrated can prevent the problems of peeling, delamination and the like caused by the lamination of two layers of materials, and realize the effect of balanced transition on the structure and further stable structure.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a radiation-cooled coating with a gradient structure according to an embodiment of the present invention;
FIG. 2 is a flow chart of a method for preparing a radiation refrigeration coating with a gradient structure according to an embodiment of the present invention;
FIG. 3 is a schematic view of an apparatus for verifying the cooling effect of a radiation refrigeration coating having a gradient structure according to the present invention;
FIG. 4 is a comparison of the surface temperature of the radiation-cooled coating of example 2 of the present invention and the ambient temperature.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of a radiation-cooled coating with a gradient structure. As shown in the figure, the coating comprises a polymer binder 1 and inorganic powder 2 which are blended, wherein the emissivity of the polymer binder in a middle infrared band (2.5-25 mu m) is higher than 0.85, and the reflectivity of the inorganic powder in a solar spectrum band (0.3-2.5 mu m) is higher than 0.85.
The invention also includes the use of a radiation-cooling coating according to the above. In use, the radiation-cooled coating comprises a radiating surface 12 and an attachment surface 11 opposite the radiating surface 12. Wherein the radiation surface 12 is used for reflecting the solar spectrum 3 and emitting the mid-infrared spectrum 4, and the attachment surface 11 is used for attaching to the substrate. The substrate comprises one or more of metal, ceramic, plastic, composite material, fixed part, and moving part. For example, the substrate may include aluminum, steel, galvanized steel, carbon fiber resin, roof tents, flexible tarpaulins, an upper layer of a roof structure, an exterior surface of an automobile, an interior surface of an automobile (e.g., a cabin surface), and the like.
In the direction Y away from the radiation surface, the content of the polymer binder 1 is gradually reduced, and the content of the inorganic powder 2 is gradually increased. Thus, a large amount of polymer binder 1 is arranged above the inorganic powder 2 in the coating, and the polymer binder 1 is used for emitting the mid-infrared spectrum 4, while the inorganic powder 2 is mainly used for reflecting the solar spectrum 3, so that a good refrigeration effect can be ensured. Meanwhile, the coating with the polymer binder 1 and the inorganic powder 2 integrated can prevent the problems of peeling, delamination and the like caused by the lamination of two layers of materials, and realize the effect of balanced transition and stable structure.
Further, in the direction Y far away from the radiation surface, the volume ratio of the polymer binder 1 to the inorganic powder 2 is gradually changed from X:1 to 1: X, wherein X is between 2 and 100, and X is between 2 and 100. The X, x optimal value range can be adjusted according to different raw material components. For a coating consisting of strong light-reflecting inorganic powder (with the reflectivity of more than 0.95) and a polymer binder with strong heat radiation emission capacity (with the emissivity of more than 0.95), X is between 2 and 100, and X is between 2 and 100; for the coating consisting of medium-strong light-reflecting inorganic powder (reflectivity, 0.9-0.95) and medium-strong heat radiation emission capability polymer binder (emissivity, 0.9-0.95), X is between 50 and 100, and X is between 50 and 100; for a coating consisting of weak light reflection inorganic powder (reflectivity, 0.85-0.9) and a weak heat radiation emission capability polymer binder (emissivity, 0.85-0.9), X is between 80 and 100, and X is between 80 and 100.
Further, the thickness of the coating is 0.1 to 1 mm. The choice of coating thickness is determined by the building substrate material to be coated: for the white lime material, the thickness of the coating is between 0.1 and 0.2 mm; for concrete materials, the thickness of the coating is 0.2-0.5 mm; for the color steel plate material, the thickness of the coating is between 0.5 and 0.7 mm; for asphalt materials, the coating thickness is between 0.7mm and 1 mm.
Further, the inorganic powder 2 includes BaSO4、TiO2、Al2O3、SiO2、CaSO4、MgO、CaCO3One or two of them. The grain diameter of the inorganic powder 2 is between 0.02 and 2 mu m; the shape of the inorganic powder 2 includes a sphere-like shape and a scale-like shape.
Furthermore, the average reflectivity of the inorganic powder in the coating in the solar spectrum band (0.3-2.5 μm) is higher than 0.85. The reflectivity of the coating in the solar spectrum band is higher than 0.9, and the emissivity in the middle infrared band is higher than 0.9.
Preferably, the average absorptivity of the polymer binder in the coating is lower than 10% in a solar spectrum band (0.3-2.5 mu m), and the average emissivity in a middle infrared band (2.5-25 mu m) is higher than 0.85. The polymer binder is one or more of non-aromatic hydrocarbon polyether, fluoride or polyester, and specifically may include one or two of polyethylene oxide (PEO), polyethylene oxide polypropylene oxide monobutyl ether, polyvinyl butyral (PVB), Ethyl Cellulose (EC), Polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), perfluorinated ethylene propylene copolymer (FEP), polymethyl methacrylate (PMMA), and polyethyl methyl acrylate (PEMA).
Fig. 2 is a flowchart of a method for preparing a radiation refrigeration coating with a gradient structure according to an embodiment of the present invention, as shown in fig. 2, the method includes:
s11, uniformly dispersing a polymer adhesive and inorganic powder in a solvent to obtain a suspension, wherein the emissivity of the polymer adhesive in a middle infrared band (2.5-25 mu m) is higher than 0.85, and the reflectivity of the inorganic powder in a solar spectrum band (0.3-2.5 mu m) is higher than 0.85;
s12, spraying or blade-coating the suspension on the substrate;
s13, slowly volatilizing the solvent to enable the content of the polymer binder to be gradually reduced and the content of the inorganic powder to be gradually increased in the direction away from the radiation surface.
Under the condition of room temperature, the polymer binder is dissolved in the solvent to form small-size molecular chains which can migrate upwards along with the volatilization of the solvent, while the inorganic powder is not dissolved and belongs to large-size particles and sinks downwards under the action of gravity, so that a gradient structure can be formed along with the continuous volatilization of the solvent, wherein the content of the polymer binder is gradually reduced and the content of the inorganic powder is gradually increased in the direction away from a radiation surface.
Further, to form a significant gradient structure, the volume fraction of solvent in the coating suspension is between 50% and 90% to ensure sufficient time and driving force during solvent evaporation to induce migration and diffusion of the polymeric binder to the radiation surface.
Preferably, the solvent is a mixture of water and an organic solvent, the volume ratio of the water in the mixture is 10-90%, and the volatilization speed of the solvent can be adjusted by adjusting the ratio of the water in the mixture, so as to better promote the formation of the gradient structure of the radiation refrigeration coating. The organic solvent is one or two of ethanol, toluene and acetone.
Further, the specific method for slowly volatilizing the solvent is as follows: the volatilization time is not less than 1 hour at the temperature of 20-40 ℃, so as to ensure that the polymer adhesive has sufficient time and driving force to migrate and diffuse to the radiation surface.
The passive refrigeration coating with the gradient structure can provide better daytime passive refrigeration effect, and can be applied to roofs, outer walls, roof structures and automobile surfaces of most buildings. In addition, the coating material is cheap and simple to construct. Therefore, the coating is a novel functional building material which integrates low cost, high performance, simple process and large-area preparation.
The radiation refrigeration coating with the gradient structure is prepared by the preparation method, the performance test of the cooling effect is carried out, meanwhile, the radiation refrigeration coating without the gradient structure is arranged as a comparative example, and the cooling effect of the radiation refrigeration coating with the gradient structure is analyzed.
Example 1
The coating described in this example consists of BaSO4And PVB. Wherein, PVB is BaSO4The mass ratio is 1:5, BaSO4The average particle diameter is 0.5 μm; coating the radiation side to the attachment side PVB BaSO4The volume ratio of (A) is gradually changed from 2:1 to 1: 10.
The preparation process of the coating is as follows: mixing BaSO4And PVB is dispersed into a certain volume of solvent according to a proportion, and then a homogenizer is adopted for processing for 30min to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 50%; the solvent is a mixture of water and ethanol, whichThe volume ratio of the reclaimed water to the ethanol is 1: 9. The suspension was brushed on a glass plate using a coater, and after drying at room temperature for 1 hour, a coating having a thickness of about 500. mu.m was formed. During drying, solvent evaporation induces migration of the polymeric binder to the radiation surface exposed to air, thereby forming a gradient structure.
The reflectance of the coating in the solar spectral band (0.3-2.5 μm) and the emissivity in the mid-infrared band (2.5-25 μm) were measured to be 0.94 and 0.96 using an ultraviolet-visible spectrophotometer with an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. The experimental device comprises a coating 100, a substrate 200 and a thermal insulation foam 300. The device was placed in an open field and the temperature of the coating surface and the ambient environment were tested separately. Tests show that the temperature of the solar water heater can be reduced by 9.2 ℃ in the afternoon at two points.
Example 2
The coating described in this example consists of BaSO4And PVB. Wherein, PVB is BaSO4The mass ratio is 1:5, BaSO4The average particle diameter is 0.5 μm; coating the radiation side to the attachment side PVB BaSO4Gradually transits from 5:1 to 1: 20.
The preparation process of the coating is as follows: mixing BaSO4And PVB is dispersed into a certain volume of solvent according to a proportion, and then a homogenizer is adopted for processing for 30min to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 65%; the solvent is a mixture of water and ethanol, wherein the volume ratio of the water to the ethanol is 2: 8. The suspension was brushed on a glass plate using a coater, and after drying at room temperature for 1.5 hours, a coating having a thickness of about 500. mu.m was formed. In this example, the solvent content is higher and the volatile drying takes longer, thus inducing the formation of a more pronounced gradient structure.
The reflectance of the coating in the solar spectral band (0.3-2.5 μm) and the emissivity in the mid-infrared band (2.5-25 μm) were measured to be 0.95 and 0.97 using an ultraviolet-visible spectrophotometer with an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions.
Tests show that the temperature of the present embodiment can be reduced by 11.5 ℃ at two points in the afternoon, and a comparison graph of the temperature and the ambient temperature is shown in fig. 4.
Example 3
The coating described in this example consists of BaSO4、TiO2And PVB. Wherein, BaSO4Average particle size of 2 μm, TiO2The average grain diameter is 20 nm; BaSO4:TiO2PVB in a mass ratio of 5:1: 1; PVB and inorganic powder (BaSO) from the radiation surface to the attachment surface of the coating4And TiO2) Gradually transits from 20:1 to 1: 50.
The preparation process of the coating is as follows: mixing BaSO4、TiO2And PVB is dispersed into a certain volume of solvent according to a proportion, and then a homogenizer is adopted for processing for 30min to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 80%; the solvent is a mixture of water and ethanol, wherein the volume ratio of the water to the ethanol is 2: 8. The suspension was brushed on a glass plate using a coater, and after drying for 2 hours at room temperature, the resulting coating had a thickness of about 500. mu.m.
The reflectance of the coating in the solar spectral band (0.3-2.5 μm) and the emissivity in the mid-infrared band (2.5-25 μm) were measured to be 0.96 using an ultraviolet-visible spectrophotometer with an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. Tests show that the temperature of the cooling tower can be reduced by 12.2 ℃ in the afternoon at two points or so.
Example 4
The coating described in this example consists of BaSO4PVB and PTFE. Wherein, BaSO4The average particle diameter is 0.5 μm; BaSO4The mass ratio of PVB to PTFE is 5:1: 1. Coating the radiation side to the attachment side Polymer Binders (PVB and PTFE) and BaSO4Gradually changes from 50:1 to 1: 100.
The preparation process of the coating is as follows: mixing BaSO4PVB and PTFE are dispersed into a certain volume of solvent according to a certain proportion, and then a homogenizer is adopted for processing for 30min to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 80%; the solvent is a mixture of water and ethanolThe volume ratio is 3: 7. The suspension was brushed on a glass plate using a coater, and after drying for 2 hours at room temperature, the resulting coating had a thickness of about 500. mu.m.
The reflectance of the coating in the solar spectral band (0.3-2.5 μm) and the emissivity in the mid-infrared band (2.5-25 μm) were measured to be 0.97 using an ultraviolet-visible spectrophotometer with an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. Tests show that the temperature of the electric kettle can be reduced by 13.4 ℃ in the afternoon or so.
Example 5
The coating described in this example is made of CaCO3And EC. Wherein, CaCO3EC mass ratio of 1:2, CaCO3The average particle diameter is 0.1 μm; coating of the radiation side to the attachment side CaCO3The volume ratio of EC is gradually changed from 2:1 to 1: 4.
The preparation process of the coating is as follows: mixing CaCO3And dispersing the EC into a certain volume of solvent according to a proportion, and then treating for 30min by using a homogenizer to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 50%; the solvent is a mixture of water and ethanol, wherein the volume ratio of the water to the ethanol is 1: 9. The suspension was brushed on a glass plate using a coater, and after drying at room temperature for 1 hour, a coating having a thickness of about 500. mu.m was formed.
The reflectance of the coating in the solar spectral band (0.3-2.5 μm) and the emissivity in the mid-infrared band (2.5-25 μm) were measured to be 0.92 and 0.95 using an ultraviolet-visible spectrophotometer with an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. Tests show that the temperature of the solar battery can be reduced by 4.6 ℃ in the afternoon.
Example 6
The coating described in this example consists of SiO2、CaSO4PVB and PEMA. Wherein, SiO2:CaSO4PVB and PEMA in a mass ratio of 1:5:1:1, SiO2Average particle diameter of 0.02 μm, CaSO4The average particle size is 1 μm; coating the radiant side to the attachment side polymeric binders (PVB and PEMA) and inorganic powders (S)iO2And CaSO4) The volume ratio is gradually changed from 2:1 to 1: 5.
The preparation process of the coating is as follows: mixing SiO2、CaSO4PVB and PEMA are dispersed into a certain volume of solvent according to a certain proportion, and then a homogenizer is adopted for processing for 30min to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 60%; the solvent is a mixture of water and acetone, wherein the volume ratio of the water to the acetone is 1: 9. The suspension was brushed on a glass plate using a coater, and after drying at room temperature for 1 hour, a coating having a thickness of about 500. mu.m was formed.
The reflectance of the coating in the solar spectral band (0.3-2.5 μm) and the emissivity in the mid-infrared band (2.5-25 μm) were measured to be 0.93 and 0.96 using an ultraviolet-visible spectrophotometer with an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. Tests show that the temperature of the solar water heater can be reduced by 7.6 ℃ in the afternoon at two points or so.
Comparative example 1
The coating described in this example consists of BaSO4And PVB. Wherein, PVB is BaSO4The mass ratio is 1:5, BaSO4The average particle size was 0.5. mu.m. BaSO in coating4PVB is homodisperse, does not have gradient structure.
The preparation process of the coating is as follows: mixing BaSO4And PVB is dispersed into a certain volume of solvent according to a proportion, and then a homogenizer is adopted for processing for 30min to obtain a uniform suspension. The volume fraction of the solvent in the suspension is 30%; the solvent is ethanol. The suspension was brushed on a glass plate using a coater, and after drying at 60 ℃ for 10min, a coating thickness of about 500 μm was formed. Pure ethanol is used as a solvent and dried under the high-temperature condition, and because the pure ethanol is volatilized quickly, the solvent volatilization is completed in a very short time, and a gradient structure is difficult to form.
The reflectivity of the coating in a solar spectrum band (0.3-2.5 microns) is 0.92 and the emissivity of the coating in a middle infrared band (2.5-25 microns) is 0.94 measured by an ultraviolet visible spectrophotometer containing an integrating sphere and a Fourier transform infrared spectrometer. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. Tests show that the temperature of the solar water heater can be reduced by 3.3 ℃ in the afternoon or so.
Comparative example 2
In this comparative example, a commercially available coating (mainly TiO) was used2) The glass plate was brushed with a coating of about 500 μm thickness. The reflectivity of the coating in a solar spectral band (0.3-2.5 mu m) and the emissivity of the coating in a middle infrared band (2.5-25 mu m) are respectively measured by an ultraviolet visible spectrophotometer containing an integrating sphere and a Fourier transform infrared spectrometer to be 0.88. In the present embodiment, the experimental apparatus shown in fig. 3 is used to measure the cooling effect of the coating under outdoor lighting conditions. Tests show that the temperature of the novel solar cell can be reduced by 1.1 ℃ in the afternoon at two points or so.
TABLE 1
Figure BDA0002518646550000091
The above tests and characterization of the examples and comparative examples were performed under the same conditions, and the comparison of the properties is shown in table 1. Obviously, the gradient structure coating provided by the invention can realize a remarkable cooling effect, and has more excellent performance than a non-gradient structure coating and a commercially available coating.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (10)

1. The radiation refrigeration coating with the gradient structure is characterized by comprising a polymer binder and inorganic powder which are blended, wherein the emissivity of the polymer binder in a middle infrared band is higher than 0.85, the reflectivity of the inorganic powder in a solar spectrum band is higher than 0.85, the content of the polymer binder is gradually reduced and the content of the inorganic powder is gradually increased in a direction far away from a radiation surface.
2. The radiation refrigeration coating of claim 1, wherein the volume ratio of the polymer binder to the inorganic powder gradually changes from X:1 to 1: X in the direction away from the radiation surface, wherein X is between 2 and 100, and X is between 2 and 100.
3. A radiation-cooled coating according to claim 2, wherein the coating thickness is 0.1-1 mm.
4. The radiation refrigeration coating as claimed in any one of claims 1 to 3, wherein the inorganic powder has a particle size of 0.02 to 2 μm.
5. The radiation refrigeration coating of any one of claims 1 to 3, wherein the inorganic powder comprises BaSO4、TiO2、Al2O3、SiO2、CaSO4、MgO、CaCO3One or two of them.
6. The use of a radiation cooling coating according to any of claims 1 to 3, wherein said radiation cooling coating comprises said radiation surface and an attachment surface opposite to said radiation surface, said attachment surface being adapted to attach to a substrate comprising one or more of metal, ceramic, plastic, composite, fixed part, moving part.
7. A preparation method of a radiation refrigeration coating with a gradient structure is characterized by comprising the following steps:
uniformly dispersing a polymer binder and inorganic powder in a solvent to obtain a suspension, wherein the emissivity of the polymer binder in a middle infrared band is higher than 0.85, and the reflectivity of the inorganic powder in a solar spectrum band is higher than 0.85;
spraying or blade coating the suspension on a substrate;
the solvent is slowly volatilized, so that the content of the polymer binder is gradually reduced and the content of the inorganic powder is gradually increased in the direction far away from the radiation surface.
8. The preparation method according to claim 7, wherein the volume fraction of the solvent in the suspension is between 50% and 90%, the solvent is a mixture of water and an organic solvent, and the volume ratio of water in the mixture is between 10% and 90%.
9. The preparation method according to claim 7, wherein the solvent is slowly volatilized by: the volatilization time is not less than 1 hour at the temperature of 20-40 ℃.
10. The method according to claim 8, wherein the organic solvent is one or two of ethanol, toluene, and acetone.
CN202010484757.8A 2020-06-01 2020-06-01 Radiation refrigeration coating with gradient structure and preparation method and application thereof Active CN111690301B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010484757.8A CN111690301B (en) 2020-06-01 2020-06-01 Radiation refrigeration coating with gradient structure and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010484757.8A CN111690301B (en) 2020-06-01 2020-06-01 Radiation refrigeration coating with gradient structure and preparation method and application thereof

Publications (2)

Publication Number Publication Date
CN111690301A true CN111690301A (en) 2020-09-22
CN111690301B CN111690301B (en) 2022-01-07

Family

ID=72479048

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010484757.8A Active CN111690301B (en) 2020-06-01 2020-06-01 Radiation refrigeration coating with gradient structure and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN111690301B (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112239328A (en) * 2020-10-13 2021-01-19 华中科技大学 Radiation refrigeration film and preparation method thereof, radiation refrigeration glass and preparation method thereof
CN112961530A (en) * 2021-02-10 2021-06-15 华中科技大学 Radiation refrigeration coating with long afterglow luminescence property and preparation method thereof
CN112961533A (en) * 2021-02-10 2021-06-15 华中科技大学 Structural color coating with daytime passive refrigeration function and preparation method thereof
CN114196268A (en) * 2022-01-06 2022-03-18 吴景秀 Radiation refrigeration coating containing high-refractive-index-difference particle combination and preparation method and application thereof
CN114434926A (en) * 2020-11-03 2022-05-06 张钟元 Intelligent refrigeration artificial leather and preparation method thereof
CN114456713A (en) * 2022-01-09 2022-05-10 电子科技大学 One-step method for constructing gradient radiation refrigeration antifouling coating and preparation method thereof
CN114854255A (en) * 2022-04-29 2022-08-05 清华大学 Composite infrared reflection coating and preparation method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101074338A (en) * 2006-05-18 2007-11-21 中国石油天然气集团公司 Acid-alkali-corrosive-resisting oil-pipe coating and its production
US20190256717A1 (en) * 2017-02-27 2019-08-22 Palo Alto Research Center Incorporated Coating to cool a surface by passive radiative cooling
CN110283481A (en) * 2019-07-19 2019-09-27 广州歌林尔新材料有限公司 A kind of inorganic coating, substrate and preparation method thereof
CN110372976A (en) * 2019-08-30 2019-10-25 哈尔滨工业大学 A kind of reflection-type radiation refrigeration material, film, preparation method and application
CN110628325A (en) * 2019-10-31 2019-12-31 宁波瑞凌新能源科技有限公司 Radiation refrigeration coating

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101074338A (en) * 2006-05-18 2007-11-21 中国石油天然气集团公司 Acid-alkali-corrosive-resisting oil-pipe coating and its production
US20190256717A1 (en) * 2017-02-27 2019-08-22 Palo Alto Research Center Incorporated Coating to cool a surface by passive radiative cooling
CN110283481A (en) * 2019-07-19 2019-09-27 广州歌林尔新材料有限公司 A kind of inorganic coating, substrate and preparation method thereof
CN110372976A (en) * 2019-08-30 2019-10-25 哈尔滨工业大学 A kind of reflection-type radiation refrigeration material, film, preparation method and application
CN110628325A (en) * 2019-10-31 2019-12-31 宁波瑞凌新能源科技有限公司 Radiation refrigeration coating

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
KOU, JL ET AL: "Daytime Radiative Cooling Using Near-Black Infrared Emitters", 《ACS PHOTONICS》 *
刘大壮等: "《溶度参数及其在涂料工业中的应用》", 31 August 2008 *
杨光等: "棕色反射隔热外墙涂层的制备及性能", 《电镀与涂饰》 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112239328A (en) * 2020-10-13 2021-01-19 华中科技大学 Radiation refrigeration film and preparation method thereof, radiation refrigeration glass and preparation method thereof
CN112239328B (en) * 2020-10-13 2022-01-07 华中科技大学 Radiation refrigeration film and preparation method thereof, radiation refrigeration glass and preparation method thereof
CN114434926A (en) * 2020-11-03 2022-05-06 张钟元 Intelligent refrigeration artificial leather and preparation method thereof
CN112961530A (en) * 2021-02-10 2021-06-15 华中科技大学 Radiation refrigeration coating with long afterglow luminescence property and preparation method thereof
CN112961533A (en) * 2021-02-10 2021-06-15 华中科技大学 Structural color coating with daytime passive refrigeration function and preparation method thereof
CN112961530B (en) * 2021-02-10 2022-06-07 华中科技大学 Radiation refrigeration coating with long afterglow luminescence property and preparation method thereof
CN114196268A (en) * 2022-01-06 2022-03-18 吴景秀 Radiation refrigeration coating containing high-refractive-index-difference particle combination and preparation method and application thereof
CN114456713A (en) * 2022-01-09 2022-05-10 电子科技大学 One-step method for constructing gradient radiation refrigeration antifouling coating and preparation method thereof
CN114854255A (en) * 2022-04-29 2022-08-05 清华大学 Composite infrared reflection coating and preparation method thereof

Also Published As

Publication number Publication date
CN111690301B (en) 2022-01-07

Similar Documents

Publication Publication Date Title
CN111690301B (en) Radiation refrigeration coating with gradient structure and preparation method and application thereof
TWI730393B (en) Composite radiative cooling film, composite radiative cooling film material and application thereof
TWI740202B (en) Radiative cooling functional coating, method for manufacturing the same and application thereof, and selective radiative cooling functional coating and composite material
CN113025133B (en) Super-hydrophobic daytime passive radiation refrigeration porous membrane and preparation method thereof
US10927244B1 (en) Superhydrophobic and self-cleaning radiative cooling film and preparation method thereof
CN112961530B (en) Radiation refrigeration coating with long afterglow luminescence property and preparation method thereof
CN110552199B (en) Radiation refrigeration composite photon structure film and preparation method thereof
CN111718584A (en) Radiation cooling film, preparation method and application thereof
CN114790350A (en) Water-based radiation cooling coating and preparation method and application thereof
CN114736566B (en) Super-hydrophobic self-cleaning temperature self-adaptive radiation cooling coating and preparation method thereof
CN109467317A (en) A kind of surface layer has the antireflecting silicon dioxide film and preparation method thereof of meso-hole structure with hole sealing structure internal layer
CN110950546A (en) High-reflection coating of solar cell glass plate and preparation method thereof
US20180269824A1 (en) Solar tiles with obscured photovoltaics
CN114506141A (en) Radiation refrigeration film
CN1546312A (en) Aerogel recombination flexible thermal insulation heat-proof thin film and process for preparing same
CN114957888B (en) PTFE three-dimensional porous radiation film and preparation method thereof
CN116515219A (en) Porous radiation refrigeration film and preparation method thereof
CN116004114A (en) Light reflection heat-preservation weather-resistant coating and preparation method and application thereof
Xia et al. Water-based kaolin/polyacrylate cooling paint for exterior walls
CN105948528A (en) High-reflection coated glass and preparation method thereof
Luo et al. UV-cured coatings for highly efficient passive all-day radiative cooling
US20240026170A1 (en) A white coating material, an intelligent thermochromic coating material and a coating layer
CN115895150A (en) Self-cleaning adjustable thermal management film
CN112961533B (en) Structural color coating with daytime passive refrigeration function and preparation method thereof
WO2022252281A1 (en) White paint that does not contain titanium dioxide, intelligent temperature-change paint, and coating

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant