376 results about "Radiative cooling" patented technology

The invention discloses a passive radiation refrigeration coating and a preparation method thereof, and relates to the technical field of industrial coatings. Comprising a fluoroacrylate emulsion, hollow glass beads, nano titanium dioxide, flaky silicon dioxide aerogel powder, polytetrafluoroethylene micro powder, hydroxyl-terminated polydimethylsiloxane, a hydroxyl acrylic acid modified silane coupling agent, a super-hydrophobic modified fluorosilicone surface additive, nano cerium oxide, aluminum fluoride doped zinc oxide infrared enhancement powder and deionized water. The paint is prepared on the basis of the formula. According to the invention, a multi-scale spectrum regulation and control and surface self-cleaning system is constructed cooperatively, so that the synergistic effect of high reflection of a sunlight region and high emission of a middle infrared region is realized. The coating can maintain continuous passive refrigeration in a day and night period, the surface of the coating has self-cleaning capability and excellent ultraviolet aging resistance, and high reflectivity and high radiation emissivity can be maintained for a long time in a complex outdoor environment, so that the thermal management efficiency of buildings and equipment is remarkably improved.

The invention relates to the technical field of refrigeration material preparation, in particular to an efficient passive radiation refrigeration material suitable for a sub-super environment and a preparation method and application of the efficient passive radiation refrigeration material. The method comprises the following steps: uniformly mixing thermoplastic polyurethane, sunlight high-reflection inorganic particles and a phase change material in a solvent; after a chemical foaming agent is added, the obtained suspension liquid is heated and foamed in a confinement mold, and wet gel is formed; and finally, carrying out freeze drying treatment to obtain the composite porous aerogel. The prepared material has a micro-nano porous skeleton formed by TPU, and inorganic particles and PCM are uniformly dispersed in the skeleton wall. Through component cooperation and a special porous structure, the material has extremely high sunlight reflectivity and mid-infrared emissivity, self-adaptive temperature regulation and control are achieved through PCM phase change, the problem that refrigeration of a traditional material fails in the sub-environment such as the vertical surface is effectively solved, and efficient sub-super-environment heat management is achieved.

The invention relates to a high-reflection-high-emissivity radiation refrigeration coating for power equipment and a preparation method of the high-reflection-high-emissivity radiation refrigeration coating. The coating comprises deionized water, styrene-acrylic emulsion, titanium dioxide, hollow glass beads, zinc oxide, hexacyclic stone powder, a dispersing agent, a defoaming agent, a coalescing agent and a mildew preventive, and mica powder, calcined kaolin, talcum powder, silicon oxide micro powder or block copolymer emulsion can be optionally added. According to the coating, the synergistic effect of various infrared functional fillers and an emulsion matrix is optimized, so that high reflection of sunlight and high emission of middle and far infrared bands are realized. The coating has excellent cooling capacity, self-cleaning performance and environmental adaptability.

The invention discloses a dynamic self-adaptive radiation refrigeration material which comprises the following components in percentage by mass: 15-30% of matrix resin, 40-60% of a ternary function system, 1-3% of a dispersing agent, 2-5% of a cross-linking agent and the balance of deionized water, the ternary function system is composed of a temperature-sensitive block copolymer, phase change microcapsules and rare earth doped infrared emission particles according to the mass ratio of (1-2): (2-3): (1-1.5). According to the refrigeration material, when the environment temperature is higher than the low critical solution temperature of the temperature-sensitive copolymer, the temperature-sensitive chain segment shrinks to expose the rare earth particles, so that high reflectivity of sunlight and high emissivity of an atmospheric window are realized, and refrigeration is enhanced; when the temperature is lower than the phase-change temperature of the phase-change material, the temperature-sensitive chain segments stretch and wrap the rare earth particles, the infrared emissivity is reduced, heat loss is reduced through phase-change heat release, the dual functions of efficient refrigeration in summer and heat loss reduction in winter are achieved, and the applicability of the coating in an area with the large temperature difference is improved.

The invention discloses a method for preparing a lignin hard carbon negative electrode material through Joule thermal flash evaporation, and belongs to the technical field of negative electrode material preparation. The method mainly comprises the following steps: (1) reacting lignin with alkali liquor, adding acid, washing with water, and drying to obtain dried lignin; (2) preheating the dried lignin in a tubular furnace to obtain a hard carbon precursor; and (3) putting the hard carbon precursor into a graphite mold, and carbonizing through Joule heat flash evaporation to obtain the lignin-based hard carbon negative electrode material. According to the method, rapid temperature rise is realized by Joule heating, and the method is short in reaction time and high in reaction temperature. Compared with a radiation cooling mode of a traditional high-temperature furnace, black-body radiation can release most heat within milliseconds. Under the action of an electric field, lignin is recombined and stacked into a vortex layer carbon layer, and a three-dimensional continuous carbon network is formed. The ultrafast method can relieve the carbon layer accumulation phenomenon in the lignin pyrolysis process.

The invention discloses a high-reflection magnesium phosphate / aluminum phosphate radiation refrigeration material and a preparation method thereof, and relates to the technical field of radiation refrigeration materials. The preparation method of the high-reflection magnesium phosphate / aluminum phosphate radiation refrigeration material comprises the following steps: (1) mixing aluminum sec-butoxide and deionized water to prepare a solution A; mgCl2. 6H2O and deionized water are mixed to prepare a solution B; mixing the solution A and the solution B to obtain a solution C; (2) adding 3-sulfopropyl tetradecyl dimethyl betaine into the solution C to obtain a solution D; (3) stirring sodium pyrophosphate and deionized water into a solution E; mixing the solution E and the solution D to obtain a solution F; and (4) reacting the solution F at 150-180 DEG C, cooling, freeze-drying and grinding to obtain H, heating H to 300-400 DEG C at the rate of 3-4 DEG C / min, then heating H to 800-1300 DEG C at the rate of 7-10 DEG C / min, and keeping the temperature for 1-3 hours to obtain the product. The material prepared by the invention has excellent sunlight reflectivity and excellent mid-infrared emissivity, and shows excellent performance in the field of radiation refrigeration.

The invention belongs to the technical field of glass for buildings, and discloses a thermochromic intelligent window based on a vanadium dioxide nanoparticle film concentration gradient structure and a preparation method thereof.The preparation method comprises the steps that firstly, two parts of W-VO2 nanoparticles with different masses and PVP are added into absolute ethyl alcohol to be subjected to ultrasonic oscillation, and the W-VO2 nanoparticles and PVP are stirred to be evenly distributed and then stand for use; the method comprises the following steps: sequentially coating the surface of a pretreated glass substrate with W-VO2amp with relatively high concentration from bottom to top; a PVP dispersion liquid, a PMMA dispersion liquid, and low-concentration W-VO2amp are added; a PVP dispersion liquid; therefore, a W-VO2 gradient structure with low concentration at the top layer and high concentration at the bottom layer is formed on the surface of the glass substrate. The visible light transmittance of the thermochromic intelligent window is greatly improved, meanwhile, the solar modulation capacity is improved, the antagonism between the two optical properties of the visible light transmittance and the solar modulation efficiency is weakened or even broken through, and thermochromic development of the intelligent window and the radiation refrigeration field is further promoted.

The invention relates to the technical field of refrigeration fibers, and particularly discloses a radiation refrigeration textile fiber and a preparation method thereof.The preparation method comprises the steps that a fluorine modifier and a styrene-maleic anhydride copolymer are dissolved in an organic solvent under the stirring and heating conditions, then fiber master batches are added, stirring continues to be conducted for 30-60 min to enable the fiber master batches to be partially dissolved, and then the radiation refrigeration textile fiber is obtained; a material A is obtained; uniformly mixing a silane coupling agent with deionized water and absolute ethyl alcohol, and then adding a pH regulator to regulate the pH value of the system to a preset value, so as to obtain a material B; uniformly stirring the material A and the material B, reacting at 60-70 DEG C for 2-5 hours, and drying to obtain modified fiber master batch; and preparing the modified fiber master batch into the radiation refrigeration textile fiber by adopting a melt spinning process. According to the method, on the premise that the mechanical strength of the fiber is not affected, the thermal emissivity of the traditional fiber in an atmospheric transparent window interval and the sunlight reflecting capacity of the fiber are greatly improved.

Permafrost thawing prevention may involve deploying a cooling geotextile onto a permafrost soil. The geotextile may include a biomass scaffold comprising natural plant-based fibers. The geotextile may further include a cellulose layer comprising cellulose fibers laminated onto the biomass scaffold such that the cellulose fibers are physically entangled with the plant-based fibers. The geotextile may further include a hydrophobic and biodegradable coating which defines at least one surface of the geotextile. The geotextile may be optically opaque, exhibits high solar reflectivity, and maintains high mid-infrared emissivity to enable passive radiative cooling.

The invention discloses a preparation method and application of a PLA (polylactic acid) / PTFE (polytetrafluoroethylene) radiation refrigeration composite film based on an electrostatic spinning method, and belongs to the field of radiation refrigeration materials. And preparing the polymer radiation composite fiber membrane by adopting an electrostatic spinning technology. The obtained micro-nano size fiber film has a porous structure, can realize a strong Mie scattering effect on solar wavelength, improves the solar reflectivity of the radiation film, and realizes the reflectivity of 85% or above within the wavelength of 400-1400 nm and the relatively high infrared emissivity of 90% within the wavelength of 8-13 [mu] m. The radiation cooling composite film has great application potential value in the field of low-temperature grain storage.

The invention discloses a Janus type flexible radiation refrigeration material and a preparation method thereof.The Janus type flexible radiation refrigeration material is characterized in that a modified radiation refrigeration layer and a functional layer are arranged on the upper surface and the lower surface of a substrate fiber layer with specific functional groups, and on one hand, the substrate fiber layer can be subjected to esterification or silanization bonding with the amino silane modified radiation refrigeration layer; the material can be subjected to an esterification reaction with a carboxylation modified functional layer, so that the three-layer material interface is chemically bonded, the bonding force of the interface is effectively improved, the dynamic stability is effectively improved on the basis of ensuring the optical performance and the mechanical flexibility, and the application of the radiation refrigeration material is promoted.

The invention provides a multifunctional radiation refrigeration material and application thereof, and the multifunctional radiation refrigeration material is used for releasing heat to space through an atmosphere window in an infrared radiation form and reflecting ultraviolet light and / or visible light and / or near-infrared light in sunlight at the same time. The multifunctional radiation refrigeration material comprises a base material and a flame-retardant material, wherein the flame-retardant material comprises one or more of a phosphorus-based material, a nitrogen-based material and a phosphorus-nitrogen-based composite material; the mass percent of the flame-retardant material in the multifunctional radiation refrigeration material is 9%-60%. The multifunctional radiation refrigeration material provided by the invention has excellent flame retardant property and radiation refrigeration effect at the same time.

The present invention relates to a flexible thermoelectric device that may be combined and attached to a curved surface and generates an electromotive force based on a temperature difference between one surface and the other surface, and more particularly, to a flexible thermoelectric device having a radiative cooling part which improves power generation performance by increasing cooling efficiency of a cooling side through radiative cooling and minimizes a volume of a heat dissipating part, and a method of manufacturing a radiative cooling part.

The invention relates to the technical field of radiation refrigeration films, and discloses a porous polyvinylidene fluoride based composite radiation refrigeration film and a preparation method thereof. The method comprises the following steps: firstly, carrying out melt blending on PVDF, NaCl and ZnO nanoparticles and forming a film, then dissolving out NaCl through water washing, and constructing a continuous three-dimensional porous structure in a PVDF matrix; and immersing the obtained porous PVDF / ZnO membrane material into a methanol aqueous solution containing 2-methylimidazole, so that ZnO is subjected to a coordination reaction at the pore wall and is converted into the ZIF-8 nanocrystal in situ. In the thin film prepared by the steps, the micron-sized salt-induced pore structure, the nano-sized ZIF-8 particles and the interface of the ZIF-8 particles jointly form a multi-stage scattering network, so that the scattering ability of the thin film in the solar spectrum range of 0.25-2.5 microns can be remarkably enhanced, the high infrared emission performance of the PVDF matrix in an atmospheric window of 8-13 microns is maintained, and the thin film has high solar reflectivity and high infrared emissivity, and can be used for preparing the solar film. An excellent radiation refrigeration effect can be achieved, and the heat-dissipating material is suitable for being applied to building outer surfaces, equipment heat dissipation, individual heat management and the like.

The invention discloses a super-hydrophobic heat insulation / radiation refrigeration integrated fabric and a preparation method thereof.The method comprises the steps that firstly, a heat insulation layer is constructed on a base fabric through electrostatic spraying, specifically, PU and SCA are dissolved in DMF, SiO2 aerogel is added to form spraying liquid, a three-dimensional network structure is formed between aerogel and fibers through the synergistic cross-linking effect of SCA and PU, the aerogel is firmly anchored, and the heat insulation layer is formed; the adhesive force and the washability of the coating are improved. PVDF-HFP and ZrO2 nano-particles are blended and spun to form a composite structure with nano-fibers wrapping ceramic particles, particle aggregation is avoided, and the radiation refrigeration and heat insulation performance of PVDF-HFP and ZrO2 nano-particles are synergistically exerted. Finally, a substrate-heat insulation-refrigeration three-dimensional composite structure is formed through hot pressing treatment, chemical bonding of all the layers is achieved through SCA, the fabric has the characteristics of high strength, abrasion resistance, hydrophobicity, heat insulation and radiation refrigeration, and the problem that durability and comfort of a traditional material are difficult to achieve at the same time is solved.

The invention relates to the technical field of coatings, in particular to a double-layer super-hydrophobic passive daytime radiation cooling coating and application thereof. The super-hydrophobic passive daytime radiation cooling coating is developed through a two-step spraying process. And the bottom layer is formed by combining a high refractive index TiO / Al2O3 composite material and modified polydimethylsiloxane. The top layer employs high band gap SiO to mitigate ultraviolet absorption and combines unmodified PDMS to ensure high thermal emissivity and low surface energy. By accurately controlling the particle size distribution and concentration gradient between the two layers of structures, the optimized SPDRC coating shows excellent optical performance, the solar reflectivity is 93.2%, and the mid-infrared thermal emissivity is 95.4%. Under the direct irradiation of the sun, the temperature reduction of 10 DEG C is obviously lower than that of the environment, and the radiation cooling power of 125 Wm <-2 > is realized. In addition, the coating has a water contact angle of 155 degrees, has strong super-hydrophobicity, can ensure excellent self-cleaning performance and long-term durability, and is suitable for actual outdoor application of building cooling.

The invention discloses a roof component based on evaporation and radiation collaborative cooling and preparation and construction thereof. The roof component breaks through the limitation of a single cooling mode through a multi-layer structure coupling evaporative cooling and radiation cooling technology. The reflective film specifically comprises a base layer, an evaporation radiation synergistic cooling material layer and a reflective protection layer. The synergistic material layer is formed by modifying polyacrylamide hydrogel through lithium bromide moisture absorption salt, titanium dioxide nanoparticles are embedded to improve the short-wave reflectivity and long-wave emissivity, and the synergistic material layer has the functions of radiation cooling and moisture absorption evaporation; the reflective protective layer is made of polyvinylidene fluoride-hexafluoropropylene copolymer, so that radiation cooling power is supplemented and pollution is prevented on the premise of moisture permeability; the heat entering a room is reduced by combining an evaporation radiation synergistic cooling material and a reflection protection material; by means of the roof component based on evaporation and radiation collaborative cooling, the limitation of cooling power can be broken through, the cooling effect is enhanced, and the purpose of building energy saving is achieved.

The invention discloses a humidity response discoloration radiation refrigeration material which comprises a scattering layer and an iridescent photon film arranged on the surface of the scattering layer, the iridescent photon film is a cellulose nanocrystal / polyethylene glycol composite film, and the scattering layer is a polylactic acid-silicon dioxide-aluminum oxide composite nanofiber film. Through the composite design of the top cellulose nanocrystal / polyethylene glycol iridescent photon film and the bottom PLA / SiO2 / Al2O3 scattering layer, coupling of color mirror reflection of the color radiation refrigeration function layer constructed by CNC / PEG composite and broadband diffusion response of the electrostatic spinning film reflecting layer is achieved, and the negative effects of moisture absorption and color development on the reflectivity are reduced; color intelligent response and efficient radiation refrigeration are successfully combined; the preparation method is simple in process, the adopted raw materials are all degradable and renewable materials, the cost is low, and industrial popularization and application are easy.

This invention discloses a colored radiation-cooling coating based on a transparent composite film and its preparation method, belonging to the technical field of colored radiation-cooling coatings for building energy conservation. The colored radiation-cooling coating based on a transparent composite film includes a surface transparent composite film layer and a bottom radiation-cooling composite layer. The bottom layer is prepared from components A and B. Component A includes transparent resin and radiation-functional fillers; the radiation-functional fillers include barium sulfate particles and hollow structured dielectric microspheres. The surface layer is prepared from components A1 and B. Component A1 includes transparent resin, a light stabilizer, and an ultraviolet absorber. The colored radiation-cooling coating based on a transparent composite film allows the radiation-cooling coating to display different colors without affecting its solar reflectivity. Simultaneously, the combination of the radiation-cooling composite layer and the transparent composite film layer improves the radiation reflection performance of the radiation-cooling coating.

The invention discloses a self-cleaning daytime radiation cooling coating and a preparation method thereof, and relates to the field of building exterior wall energy-saving coatings. The preparation method comprises the following steps: uniformly dispersing a first filler and a second filler in a butyl acetate solvent, sequentially adding a silane coupling agent and a third filler, uniformly dispersing, finally adding fluorocarbon resin and a curing system thereof, and dihydroxyl-terminated polydimethylsiloxane and a curing system thereof, and uniformly dispersing to obtain the self-cleaning daytime radiation cooling coating. The self-cleaning daytime radiation cooling coating prepared by the invention is high in hardness and strong in adhesive force, and also has a super-hydrophobic self-cleaning function and an optical property of realizing daytime radiation cooling. The coating is simple in preparation process, low in equipment requirement and suitable for large-scale production.

The invention discloses a radiation refrigeration electric control dimming film with a near-infrared light absorption function, belongs to the technical field of radiation refrigeration materials, and solves the problem that an electric control dimming film in the prior art cannot meet the requirements of light adjustment and temperature control at the same time. The electrically-controlled dimming film is prepared from the following raw materials in parts by weight: 50-80 parts of micromolecular liquid crystals, 20-50 parts of polymerizable monomers, 0.1-5 parts of a photoinitiator, 1-5 parts of inorganic nanoparticles and 0.1-1 part of spacer particles, wherein the micromolecular liquid crystal is any one of E7, E8, SLC-1717 and GXP-6033 or a mixture of more of E7, E8, SLC-1717 and GXP-6033. The dimming film has the characteristic of high emissivity in a mid-infrared atmosphere window wave band, heat can be dissipated to outer space in an infrared radiation mode, and zero-energy-consumption passive cooling is achieved.

The invention relates to the technical field of coatings, and discloses a modified aerogel, a preparation method thereof and an application of the modified aerogel in a radiation refrigeration coating. The method comprises the following steps: in the presence of water, a solubilizer and an acid catalyst, carrying out hydrolysis reaction on a silicon source to obtain silica sol; in the presence of a base catalyst, contacting the silica sol with a rare earth oxide with a linear average particle size of 10-100 nm to carry out a gel reaction so as to obtain a modified wet gel; and drying the modified wet gel at normal pressure to obtain the modified aerogel, the adding amount of the rare earth oxide and the normal-pressure drying condition are controlled, so that the content of the rare earth oxide in the modified aerogel is 0.5-1 wt%. A coating prepared from the radiation refrigeration composition containing the modified aerogel prepared by the invention has the characteristics of high sunlight reflectivity, high atmospheric window emissivity and the like.

The invention discloses a passive radiation-cold storage composite box body and a preparation method. The box body sequentially comprises a composite radiation film, a heat insulation layer and a cold storage layer from outside to inside. The outer-layer radiation film is composed of an elastic organic matrix and high-reflection inorganic particles such as barium sulfate, has high solar reflectivity and mid-infrared high emissivity, and can effectively restrain solar absorption and achieve radiation heat dissipation in the daytime. The heat insulation layer is made of XPS, EPS, aerogel felt and other low-heat-conduction materials so as to reduce external heat transfer. Phase change microcapsules are dispersed in the cold storage layer, and flake graphite and other high-thermal-conductivity fillers can be added to improve the cold transfer efficiency and temperature uniformity. And the phase-change material realizes automatic cold storage and cold release through a latent heat mechanism, so that the temperature in the box body is kept stable. Through the synergistic effect of radiation refrigeration, heat insulation and phase change cold storage, long-time and recyclable passive cold chain temperature control is achieved, and the device has the advantages of being simple and convenient in structure, high in cost performance, flexible in application, uniform in internal temperature distribution and the like.

The invention provides a packaging front plate, a preparation method thereof and a photovoltaic module. The packaging front plate comprises a body which is of a transparent structure; the radiation cooling layer is arranged on the surface of one side of the body, the radiation cooling layer has light transmittance, and the face, away from the body, of the radiation cooling layer is provided with a lotus leaf surface imitating micro-nano structure. The radiation cooling layer can radiate heat to the external space, so that the working temperature of the photovoltaic module is effectively reduced, the photoelectric conversion efficiency can be improved, the photovoltaic module can be prevented from running at a high temperature, and the service life of the photovoltaic module can be prolonged; furthermore, a micro-nano structure imitating the lotus leaf surface is designed on the radiation cooling layer, attachment of water drops or dirt on the surface of the radiation cooling layer can be reduced, and therefore the surface of the radiation cooling layer is kept clean and dry, the problem that the power generation efficiency is reduced due to pollution can be avoided, the cleaning frequency can be reduced, and the power generation efficiency is improved. And therefore, the maintenance cost can be reduced.

The invention discloses a preparation method of an h-BN / BMSC daytime radiation refrigeration material, which comprises the following steps: (1) blending 39.9-66.5 parts by mass of few-layer h-BN nanosheets and 133 parts by mass of light calcined magnesia, and slowly stirring to obtain a mixed material; (2) dispersing an additive into 61 parts by mass of a magnesium sulfate heptahydrate solution, uniformly mixing, adding into the mixed material in the step (1), and stirring at a high speed to obtain slurry; and (3) putting the slurry obtained in the step (2) into a mold, and curing at room temperature to obtain the few-layer h-BN / BMSC composite material. The prepared gelling-based composite material has good radiation cooling performance and heat dissipation performance in an outdoor high-temperature environment, and can be used as a radiation cooling heat dissipation material with the temperature higher than the environment temperature. The passive cooling heat dissipation plate has important significance in improving the working efficiency of outdoor electronic equipment in a high-temperature environment, prolonging the service life and guaranteeing the reliability of a system.

The invention relates to the technical field of building energy conservation and water resource utilization, and discloses a multifunctional AKLBT dual-network hydrogel system and a preparation method and application thereof, the multifunctional AKLBT dual-network hydrogel system comprises AKLBT dual-network hydrogel and a PAN / PVDF coated CNTs / ppy composite photo-thermal layer; wherein the AKLBT dual-network hydrogel takes acrylamide and konjac glucomannan as monomers, and LiCl, BaSO4 and TiO2 are doped into the monomers; the PAN / PVDF-coated CNTs / ppy composite photo-thermal layer is attached to the surface of the hydrogel to construct a photo-thermal conversion interface. Through a three-in-one synergistic mechanism of radiation cooling, adsorption water collection and photo-thermal evaporation, zero-energy-consumption cooling of the building and efficient capture of atmospheric water resources are achieved, stable recycling can be achieved, and an integrated solution is provided for building hydrothermal collaborative management.

The invention discloses switchable thermal management-self-energized sensing integrated high-breathability leather as well as a preparation method and application thereof, and belongs to the technical field of functional leather and intelligent wearable equipment. The radiation cooling side and the radiation heating side are designed on the two sides of the leather base body respectively, the radiation cooling side is composed of a porous bonding layer and an electrostatic spinning radiation cooling fiber membrane, and a through pore channel is formed to improve the moisture permeability efficiency; the radiation heating side achieves the efficient heating function through the vapor deposition photo-thermal polymer, the leather can autonomously switch the cooling mode or the heating mode according to the environment temperature and humidity through the combination of the two, meanwhile, self-energy-supply sensing is achieved through the integrated preset electrode, and human body movement can be monitored through the triboelectric effect without an external power source. The dynamic thermal management capability can adapt to seasons and day and night temperature differences, the limitation of a traditional single function is broken through, the problems that a coating is blocked, inorganic materials are prone to falling off, air permeability is reduced and the like are solved, and a multifunctional integrated solution is provided for intelligent wearable equipment.

A colored bilayer sub-ambient radiative cooling coating designed to enhance solar reflectance and aesthetic coloration is introduced. The coating includes a white bottom layer containing TiO2 or ZrO2 nanoparticles, and hollow glass spheres dispersed in a polymer matrix, and a colored top layer containing SiO2 microspheres and fluorescent pigments selected from Sr2Si5N8:Eu2+, Y3A15O12:Ce3+, (Ba,Sr)SiO4:Eu2+, or SrO·Al2O3:Eu phosphors dispersed in a polymer matrix. This bilayer structure achieves an effective solar reflectance of at least 90% and reduces surface temperature by at least 3° C. compared to ambient air, providing energy-efficient cooling with aesthetic appeal.

This application provides a layered, environmentally friendly waterborne radiative cooling coating composition, belonging to the field of radiative cooling. The coating composition includes a waterborne radiative cooling primer, a topcoat, and a clear coat. The primer comprises 20-50 parts of a first waterborne emulsion, 10-20 parts of a narrow bandgap optical scatterer, and 10-20 parts of a wide bandgap optical scatterer. The topcoat comprises 20-50 parts of a second waterborne emulsion and 30-60 parts of a wide bandgap optical scatterer. The clear coat comprises 20-50 parts of a third waterborne emulsion. This coating utilizes a synergistic layering of primer / topcoat / clear coat and optimized wide bandgap filler gradation to achieve high solar reflectivity and mid-infrared emissivity at a thinner film thickness, resulting in significant passive cooling. The all-waterborne system disperses and dries at room temperature, resulting in low energy consumption and no VOC risk. The layered structure enhances adhesion, weather resistance, and self-cleaning properties. Compared to high-filler thick-coating processes, this application saves raw materials, energy consumption, and construction steps, extends maintenance cycles, and reduces total life-cycle costs.

The goal is to reduce the heating load in winter and the cooling load in summer. [Solution] The membrane structure building comprises a double membrane that constitutes the exterior of the building and has an inner membrane and an outer membrane having a radiative cooling function, and an air blower / discharge device that switches between an insulating mode in which air is blown into the double membrane to form an air layer between the inner membrane and the outer membrane, and a solar radiation shielding mode in which air is discharged from the double membrane to bring the inner membrane and the outer membrane into contact.