Self-leveling heat-insulating coating, coating and process of self-leveling heat-insulating coating

Abstract

The invention discloses a self-leveling heat-insulating coating which comprises a powder component A serving as a framework and a reaction matrix of a self-leveling system, the emulsion component B is used as a reaction medium and a flexible network of a self-leveling system; the composite settling temperature-regulating particles as a self-leveling system are settled close to the base plane by gravity; deionized water; and the heat insulation and heat preservation performance of the house flat roof heat insulation coating is further improved.

Description

Technical Field

[0001] This invention belongs to the field of coatings. Background Technology

[0002] The core principle of outdoor coatings containing phase change paraffin is to utilize the property of paraffin to absorb or release a large amount of latent heat when it undergoes a solid-liquid phase change at a specific temperature, thereby achieving adaptive temperature control of the building surface. Currently, phase change paraffin is added to coatings in the following two forms:

[0003] The first method involves directly dispersing paraffin wax in the self-leveling coating emulsion. Since phase change paraffin wax melts into a liquid state above its phase change temperature (e.g., 35°C), it loses its solid form and seeps out from the coating matrix. Experiments show that coatings with 30% paraffin wax added directly to the insulation coating exhibit oily seepage on the surface after 30 thermal cycles, with a leakage rate >15%. An oil film forms on the coating surface, contaminating the wall and completely losing its temperature-regulating function. Liquid paraffin wax creates "pore channels" during the coating film-forming process, leading to a 40% decrease in tensile strength (from 8 MPa to 4.8 MPa), accelerating moisture penetration, and causing a sharp drop in the coating's weather resistance (blistering after 72 hours of salt spray testing). Simultaneously, the non-polar molecules of paraffin wax have poor compatibility with common coating resins (such as acrylic and epoxy). When directly mixed, paraffin wax aggregates at the interface, forming a "weak boundary layer." Adhesion tests show that the pull-out strength decreases from 2.5 MPa to 0.8 MPa (risk of detachment increases by 300%).

[0004] The second approach involves microencapsulating paraffin phase change material (PCM) into micron-sized capsules and incorporating them into exterior wall coatings. However, this micron-sized microcapsule incorporation requires uniform distribution of the PCM within the coating. PCM microcapsules near the outer layer of the coating are significantly affected by ambient temperature, and the latent heat released and absorbed during the phase change is quickly absorbed by the environment, thus failing to achieve effective heat storage. Furthermore, these microcapsule shells are fragile and prone to rupture. During coating mixing, application (scraping, rolling, etc.), and subsequent use (e.g., thermal stress cycling, wind pressure, minor impacts), the microcapsule shells may rupture, leading to PCM leakage. Leaked liquid paraffin can contaminate the coating surface, affecting appearance, and may even seep into the wall. More seriously, it can cause the phase change function to fail. This micron-sized microcapsule shell material and the leaked paraffin may also be more sensitive to environmental factors such as ultraviolet radiation, moisture, and temperature cycling, accelerating coating aging, chalking, discoloration, or peeling. Summary of the Invention

[0005] Purpose of the invention: In order to overcome the shortcomings of the existing technology, the present invention provides a self-leveling thermal insulation coating, coating and process thereof, to further improve the thermal insulation performance of the thermal insulation coating for flat roofs.

[0006] Technical solution: To achieve the above objectives, the present invention provides a self-leveling thermal insulation coating, comprising the following components:

[0007] Powder component A serves as the framework and reactive matrix of the self-leveling system;

[0008] Component B of the emulsion serves as the reaction medium and flexible network of the self-leveling system;

[0009] As a self-leveling system, gravity settles the composite settling temperature-regulating particles close to the base surface;

[0010] Deionized water.

[0011] The weight ratio of powder component A, emulsion component B, deionized water, and composite sedimentation temperature-regulating particles is 3:2:1:2.

[0012] Component A of the powder includes: phosphogypsum-based cementitious materials, cement, phosphogypsum waste powder, 50-60 mesh recycled glass fine aggregate, 80-150 mesh quartz sand, hemihydrate gypsum, lignin sulfonate water-reducing agent, polyacrylonitrile-based carbon fiber, hollow glass microspheres, and active crystallization components.

[0013] Component B of the emulsion includes acrylate copolymer emulsion, silicone oil emulsion defoamer, organosilicon leveling agent, sodium gluconate, nano-SiO2 dispersion, and deionized water.

[0014] Each single composite settling temperature-regulating particle is spherical in shape. It includes a hollow metal sphere with a negative pressure injection port. The hollow part inside the hollow metal sphere is filled with phase change paraffin wax. The outer surface of the hollow metal sphere is covered with a polyethylene encapsulation layer. The overall density of any single composite settling temperature-regulating particle is greater than the density of the liquid formed by mixing component A (powder), component B (emulsion), and deionized water.

[0015] The composite thermal insulation coating includes a self-leveling emulsion-cured insulation layer. The portion of the self-leveling emulsion-cured insulation layer close to the horizontal construction surface of the roof contains embedded composite settling temperature-regulating particles. Each individual composite settling temperature-regulating particle includes a hollow metal sphere. Each hollow metal sphere has a hollow negative pressure injection port. The hollow part inside the hollow metal sphere is filled with phase change paraffin wax. The outer surface of the hollow metal sphere is covered with a polyethylene encapsulation layer.

[0016] Preparation process of composite settling temperature-regulating particles for self-leveling thermal insulation coatings:

[0017] Step 1: Mass-produce hollow metal spherical particles using molding and centrifugal spinning.

[0018] Step 2: Using laser precision drilling, negative pressure injection ports are opened on each hollow metal sphere formed in Step 1 in batches.

[0019] Step 3: Place the batch of hollow metal spherical particles with negative pressure injection ports into a sealed container, and then use a vacuum negative pressure device to draw a vacuum into the sealed container. Shake the container appropriately so that the air inside each hollow metal spherical particle is discharged under the action of the vacuum environment, thereby making the interior of all the perforated hollow metal spherical particles in the container enter a vacuum state.

[0020] Then slowly open the paraffin liquid injection valve at the bottom of the sealed container. Under the action of the vacuum negative pressure of the sealed container cavity, the molten paraffin is sucked into the bottom of the container vacuum cavity. Let the paraffin liquid level rise slowly and gradually completely submerge all the perforated hollow metal spheres. Keep the molten paraffin completely submerged in all the hollow metal spheres and maintain the vacuum state for a period of time of more than 15 minutes.

[0021] The vacuum state inside the sealed container is slowly released. Under the action of vacuum negative pressure, the molten paraffin liquid is drawn into each vacuum-state hollow metal sphere through the negative pressure injection port, so that each hollow metal sphere is filled with paraffin liquid.

[0022] Then drain the excess paraffin liquid from the container. After it is completely drained, a thin layer of paraffin will be attached to the surface of the metal spheres in the container. Place the hollow metal spheres filled with paraffin into an oven at a temperature higher than the melting point of paraffin, such as 70-80°C, and bake them so that the paraffin layer attached to the surface will melt and flow away.

[0023] Step 3: The hollow metal spherical particles obtained in Step 3 are coated with polyethylene using a fluidized bed coating method to obtain the final composite sedimentation temperature-regulating particles.

[0024] Construction process of self-leveling thermal insulation coating:

[0025] S1, the emulsion composed of powder component A, emulsion component B, and deionized water is applied as a primer on the horizontal construction surface of the roof using a roller coating method;

[0026] S2, after the primer coating is completed and the surface is dry for 3 hours, pour a predetermined amount of emulsion consisting of powder component A, emulsion component B, and deionized water into the enclosed construction surface; so that an uncured thick self-leveling thermal insulation coating is formed on the surface of the horizontal construction surface of the roof.

[0027] S3 involves uniformly and discretely spreading composite settling temperature-regulating particles onto a thick self-leveling insulation coating. While maintaining uniform dispersion, accumulation is avoided. Under the influence of gravity, the composite settling temperature-regulating particles spread in the thick self-leveling insulation coating automatically sink to a position close to the horizontal construction surface of the roof.

[0028] Beneficial effects: The composite settling temperature-regulating particles of the self-leveling emulsion curing insulation layer of this invention are embedded in a discretely distributed state near the horizontal construction surface of the roof. The particles are brought close to the base surface by gravity settling, which can accurately absorb the residual heat flow transmitted from the building surface through the heat insulation layer formed by the self-leveling coating, forming a gradient heat absorption, and further significantly reducing the heat energy transferred to the room.

[0029] During the daytime, the low thermal conductivity of the self-leveling emulsion-cured insulation layer effectively blocks the transfer of external heat to the interior. At this time, because the discretely distributed composite settling temperature-regulating particles are located on the side away from the high-temperature environment, the phase change process is slowed down. The subsequent phase change process effectively achieves gradient heat absorption, further significantly reducing the transfer of heat energy to the room.

[0030] When the ambient temperature drops below the solidification point of paraffin, the composite settling temperature-regulating particles, which are discretely distributed, are located on the side away from the high-temperature environment. As a result, the composite settling temperature-regulating particles will not cool down immediately and rapidly, thus achieving the purpose of delaying the heat release process of phase change. During the heat release process of phase change, the self-leveling emulsion curing insulation layer also delays the heat dissipation of the composite settling temperature-regulating particles.

[0031] In this solution, the phase change paraffin is encapsulated within hollow metal spheres with a macroscopic structure. The contraction and expansion of the paraffin phase change process are completed within the robust hollow metal sphere particles, preventing compression and contraction of the self-leveling emulsion curing insulation layer. This eliminates the problem of coating cracking caused by the expansion and contraction of the phase change material during the phase change process. At the same time, the synergistic effect of the polyethylene encapsulation layer and the robust hollow metal sphere particles effectively prevents paraffin leakage, significantly improving the phase change cycle life in principle. Furthermore, the composite settling temperature-regulating particles themselves have a rigid structure, providing excellent support and thus improving compressive strength. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the coating cross-section;

[0033] Figure 2 This is a schematic diagram of a single composite sedimentation temperature-regulating particle. Detailed Implementation

[0034] The invention will now be further described with reference to the accompanying drawings.

[0035] This self-leveling coating adopts a unique four-component design (powder component A + emulsion component B + deionized water + composite settling temperature-regulating particles). In this solution, the component ratio of these four components is: powder component A : emulsion component B : deionized water : composite settling temperature-regulating particles = 3 : 2 : 1 : 2 (by weight).

[0036] 1. Powder components (component A)

[0037] The powder composition forms the framework and reactive matrix of the self-leveling system, providing basic strength while ensuring leveling properties through gradation optimization; the specific formulation is as follows:

[0038]

[0039] The active crystalline component is composed of three functional materials listed in the table below, achieving infiltration crystallization through synergistic particle size distribution and chemical activity. Specific formulations are as follows:

[0040]

[0041] The aforementioned phosphogypsum-based cementitious material is a hydraulic cementitious material formed by mixing phosphogypsum as the main calcium source (accounting for 40–50%), composite slag (45–55%), alkaline activator (carbide slag 0.5–5%), and silica fume (2–10%) and reacting them at room temperature.

[0042] The aforementioned phosphogypsum waste powder is an ultrafine powder produced by pretreatment, grinding, and modification of solid waste residue (mainly CaSO4·2H2O, containing small amounts of phosphorus, fluorine, and other impurities) generated during the wet-process phosphoric acid production process. The powder has a particle size ≤80μm and a specific surface area of ​​300–600m². 2 / kg.

[0043] Characteristics of component A:

[0044] Aggregate composition: 50-60 mesh recycled glass fine aggregate is compounded with 80-150 mesh quartz sand to ensure suspension stability and avoid aggregate settling or segregation during 6mm thick layer construction.18

[0045] Lightweight insulation unit: The addition of hollow glass microspheres reaches 12%, reducing the coating density to 1.45 g / cm³. 3 (Traditional cement-based coatings have a content of approximately 1.8-2.0 g / cm³) 3 The thermal conductivity was optimized to 0.08 W / (m·K)10.

[0046] Fiber-reinforced design: Polyacrylonitrile-based carbon fiber improves the bonding strength with cement interface, increasing crack resistance by 40%.

[0047] The actual proportions of component A:

[0048] Components weight phosphogypsum-based cementitious materials 250 cement 130 Phosphogypsum waste residue powder 105 50-60 mesh recycled glass fine aggregate 190 80-150 mesh quartz sand 230 hemihydrate gypsum 48 Lignosulfonate water-reducing agent 4 Polyacrylonitrile-based carbon fiber 39 Hollow glass microspheres 90 Active crystalline components 32

[0049] Powder preparation process of component A

[0050] Premixing: Add phosphogypsum-based cementitious materials, cement, and hemihydrate gypsum into a conical ribbon mixer and mix at a low speed of 30 r / min for 5 minutes to break up lumps.

[0051] Aggregate gradation: Add phosphogypsum waste powder, 50-60 mesh recycled glass fine aggregate, and 80-150 mesh quartz sand in sequence, increase the rotation speed to 45 r / min, and continue for 10 minutes until macroscopically uniform.

[0052] Fiber dispersion: Polyacrylonitrile-based carbon fibers are premixed with 1 / 2 of the amount of hollow glass microspheres and gradually sprinkled in to avoid fiber agglomeration; then the remaining special components are injected through an air jet system, and finally mixed at 45 r / min for 15 minutes until the variance coefficient is <5% (uniformity); Sieving and packaging: agglomerates are removed by 0.6 mm vibrating sieve and sealed in moisture-proof packaging.

[0053] 2. Emulsion component (component B)

[0054] Emulsions provide a reaction medium and a flexible network, endowing the system with rheological properties and environmental tolerance.

[0055]

[0056]

[0057] Characteristics of emulsion component (component B):

[0058] A vinyl acetate-butyl acrylate copolymer emulsion (Tg = -15℃) is used. An anionic / nonionic composite emulsion system (SN-15:COPS-1 = 1:1) is used to improve electrolyte stability and prevent flocculation upon contact with cement. Nano-SiO2 is pre-dispersed in the emulsion to fill the pores of the polymer network, thereby increasing the hardness of the coating by 20% and extending the UV aging resistance time to 2000 hours.

[0059] The actual proportions of component A:

[0060] Components weight Acrylic copolymer emulsion 560 silicone oil emulsion defoamer 4 Organosilicon leveling agent 3 Sodium gluconate 5 <![CDATA[Nano - SiO2 dispersion liquid]]> 24 Deionized water 19

[0061] Mixing process of emulsion component (component B):

[0062] Step 1: Add all of the acrylate copolymer emulsion and stir at low speed (300-500 rpm);

[0063] Step 2: Add half of the silicone oil defoamer and stir at 300-600 rpm for 5-10 minutes.

[0064] Step 3: Add silicone leveling agent; maintain 400-600 rpm and stir for 5-10 minutes.

[0065] Step 4: Slowly add sodium gluconate diluted with 80% deionized water and stir (600-800 rpm) for 10-15 minutes.

[0066] Step 5: Adjust the speed to 300-400 rpm and slowly add the nano-SiO2 dispersion; after the addition is complete, increase the speed to 600-700 rpm and stir for 15-20 minutes.

[0067] Step 6: Adjust the viscosity with the remaining deionized water; and add the remaining defoamer (400-600 rpm) and stir for 5-10 minutes.

[0068] Step 6: Stop stirring and let it stand for 15-30 minutes to mature. After maturation, stir at low speed (200-400 rpm) for 3-5 minutes to obtain the emulsion component (component B).

[0069] 3. The mixing process of powder component A, emulsion component B, and deionized water:

[0070] Formulation ratio: Component A (powder): Component B (emulsion): deionized water = 3:2:1 (by weight);

[0071] Mixing procedure: First, pour component B into the mixing tank and add 2 / 3 of the deionized water for premixing; pour component A into the mixture at a constant speed over 30 seconds, then add the remaining 1 / 3 of the deionized water, and use a planetary mixer (mix at low speed of 300 rpm for 30 seconds, then switch to high speed of 1200 rpm for 90 seconds).

[0072] Viscosity control: The viscosity of the mixed slurry is controlled at 8500±500cps (Brookfield DV2T, rotor 63#), exhibiting a smooth, silky flow dynamic.

[0073] 4. Composite settling temperature-regulating particles:

[0074] The specific structure of a single composite sedimentation temperature-regulating particle 1:

[0075] The single composite settling temperature regulating particle 1 is a spherical particle with an outer diameter of 5mm to 6mm. The single composite settling temperature regulating particle 1 includes a hollow metal sphere 4. The hollow metal sphere 4 is made of 316L stainless steel. A 0.3mm negative pressure injection port 3 is hollowed out on the hollow metal sphere particle 4. The hollow part inside the hollow metal sphere particle 4 is filled with phase change paraffin wax 2. The outer surface of the hollow metal sphere particle 4 is covered with a polyethylene encapsulation layer 5. By adjusting the specific gravity of the hollow metal sphere particle 4, the overall density of the single composite settling temperature regulating particle (1) is greater than the liquid density of the mixture of component A (powder), component B (emulsion), and deionized water.

[0076] Mass production process of composite sedimentation temperature-regulating granules 1:

[0077] Step 1: Mass-produce hollow metal spherical particles using molding and centrifugal spinning method 4:

[0078] Process Principle: A combination mold (lower mold with a concave hemispherical cavity, upper mold with a convex hemispherical column) is used. A mixture of metal powder and binder is fed into the mold. After mold closing, heating and rotation are employed, and centrifugal force ensures the material adheres evenly to the inner wall of the spherical cavity. Mold: Concave hemispherical diameter 5mm, convex hemispherical diameter 3–4mm (wall thickness controlled at 0.5–1mm); Feed ratio: Metal powder (stainless steel) 50–70 vol%, binder (paraffin or polyethylene); Rotation conditions: 400–600 rpm, holding temperature 65–130℃ to soften the material, centrifugation for 2–3 minutes; Dozens to hundreds of semi-forms can be produced in a single batch. After sintering, the spherical roundness error is <0.05mm, and the wall thickness uniformity is >90%.

[0079] Step 2: Using laser precision drilling, 0.3mm microholes (negative pressure injection port (3)) are opened on each hollow metal sphere (4) formed in Step 1; Equipment: UV / picosecond laser (cold processing to reduce heat effect); Parameter control: pulse energy ≤50μJ, frequency 20–100kHz; focused spot diameter ≈0.3mm, air blowing to assist chip removal, single hole processing time <1 second, hole diameter tolerance ±0.02mm, no burrs.

[0080] Step 3: Place the batch of hollow metal spherical particles 4 with negative pressure injection ports 3 into a sealed container, and then use a vacuum negative pressure device to draw a vacuum into the sealed container. Shake the container appropriately so that the air inside each hollow metal spherical particle 4 is discharged under the action of the vacuum environment, thereby making the interior of all the perforated hollow metal spherical particles 4 in the container enter a vacuum state.

[0081] Then, slowly open the paraffin liquid injection valve at the bottom of the sealed container. Under the action of the vacuum negative pressure in the sealed container cavity, the molten paraffin is drawn into the bottom of the container vacuum cavity. Allow the paraffin liquid level to rise slowly, gradually and completely submerging all the hollow metal spheres 4 with holes. Keep the molten paraffin completely submerging all the hollow metal spheres 4 and maintain the vacuum state for a period of time of more than 15 minutes. During this period, let the vacuum negative pressure continue to act to extract the residual gas in each hollow metal sphere 4.

[0082] The vacuum state inside the sealed container is slowly released. At this time, each hollow metal sphere 4 is still in a vacuum state. Molten paraffin liquid is drawn into each vacuum state hollow metal sphere 4 through the negative pressure injection port 3 under the action of vacuum negative pressure, so that each hollow metal sphere 4 is filled with paraffin liquid.

[0083] Then, drain the excess paraffin liquid from the container. After it is completely drained, a thin layer of paraffin will be attached to the surface of the metal spheres in the container. Place the hollow metal spheres 4 filled with paraffin into an oven with a temperature higher than the melting point of paraffin (e.g., 70-80℃) and bake them so that the paraffin layer attached to the surface will melt and flow away.

[0084] Step 3: The hollow metal spherical particles (4) obtained in Step 3 are coated with polyethylene using a fluidized bed coating method (batch method) to obtain the final composite settling temperature-regulating particles 1.

[0085] The specific process of this step is as follows: Hollow metal spherical particles 4 are loaded into a fluidized bed, and preheated air (flow rate 0.5–1.5 m / s) is introduced to make the hollow metal spherical particles 4 uniformly fluidized; high-density polyethylene (HDPE) powder (particle size 80–120 mesh) is sprayed in, and the bed temperature is controlled slightly higher than the melting point of polyethylene (130–150℃); coating time: 3–8 minutes, and the thickness is controlled by time (target thickness 200 μm); suitable for continuous production, with a single processing capacity of up to several hundred kilograms and high coating uniformity.

[0086] 5. Construction process;

[0087] S1, the emulsion composed of powder component A, emulsion component B and deionized water is applied as a primer on the horizontal construction surface 7 of the roof by roller coating, and the primer thickness is 1mm to 2mm.

[0088] S2, after the primer coating of the enclosed construction surface is completed and surface dry for 3 hours, pour a predetermined amount of emulsion composed of powder component A, emulsion component B, and deionized water into the enclosed construction surface, with a pouring thickness of 15mm; use a toothed scraper to initially spread and assist in the flow, and use a needle roller to roll and defoam within 10 minutes after pouring; thus forming an uncured thick self-leveling thermal insulation coating on the surface of the horizontal construction surface 7 of the roof.

[0089] S3, the composite settling temperature regulating particles 1 are evenly spread on the thick self-leveling thermal insulation coating in a discrete manner using the screen uniform spreading method. While maintaining uniform dispersion, accumulation is avoided. The composite settling temperature regulating particles 1 spread in the thick self-leveling thermal insulation coating automatically sink to the horizontal construction surface 7 close to the roof under the action of gravity.

[0090] S4, initial curing: Do not step on it within 12 hours after application, cover with plastic film to prevent rain; drying period: can be walked on after 24 hours at 20℃, reaches 80% strength in 7 days, and is fully cured in 28 days.

[0091] 6. The working principle of this composite heat insulation coating and its high-efficiency temperature control:

[0092] The composite thermal insulation coating includes a self-leveling emulsion-cured insulation layer 6 with a thickness exceeding 15 mm. The portion of the self-leveling emulsion-cured insulation layer 6 close to the horizontal roof surface 7 contains discretely distributed embedded composite settling temperature-regulating particles 1. Each individual composite settling temperature-regulating particle 1 includes a hollow metal sphere 4, with a 0.3 mm negative pressure injection port 3 perforated on the hollow metal sphere 4. The hollow portion inside the hollow metal sphere 4 is filled with phase change paraffin wax 2, and the outer surface of the hollow metal sphere 4 is coated with a… The polyethylene encapsulation layer 5; the phase change paraffin 2 in this solution is encapsulated in a hollow metal sphere 4 with a macroscopic structure. The contraction and expansion of the paraffin phase change process are completed inside the solid hollow metal sphere particles 4, which will not cause compression and contraction to the self-leveling emulsion curing insulation layer 6, thereby eliminating the problem of the phase change material promoting coating cracking due to the expansion and contraction of the phase change process; at the same time, the solid synergistic effect of the polyethylene encapsulation layer 5 and the hollow metal sphere particles 4 effectively prevents paraffin leakage, and significantly improves the phase change cycle life in principle.

[0093] Without introducing the composite settling temperature-regulating particles 1 of this scheme, the test performance parameters of the self-leveling emulsion-cured insulation layer 6 of this scheme are shown in the table below:

[0094] compressive strength ≥25MPa GB / T 23445-2009 Flexural strength ≥8MPa GB / T 23445-2009 Bond strength ≥1.8MPa JC / T 907-2018 elastic modulus 8,000-10,000 MPa ISO 527-1 thermal conductivity ≤0.08W / (m·K) GB / T 10294-2008 Permeability 0.3MPa / 30min impermeable GB / T 16777-2008 Freeze-thaw resistance No cracking after 100 cycles JGJ / T 70-2009 UV aging resistance 2000hΔE≤3.0 ASTM G154 Drying time Surface drying time ≤ 4 hours, actual drying time ≤ 12 hours GB / T 1728-1979 Flame retardant rating UL94 V-0 IEC 60695-11-10

[0095] As can be seen, this solution achieves self-leveling performance and long-term waterproof and thermal insulation functions at a high thickness (20mm) by optimizing the synergistic effect of polymer and cement. It integrates the rigidity and toughness balance of polymer and cement, the thermal insulation properties of lightweight aggregate, and the durability enhancement of nano-reinforcement, thus meeting the special environmental requirements of roofs.

[0096] Based on this, the self-leveling emulsion curing insulation layer 6, which is close to the horizontal construction surface 7 of the roof, has a discretely distributed embedded composite settling temperature regulating particles 1. The particles are brought close to the base surface by gravity settling, which can accurately absorb the residual heat flow transmitted from the building surface through the heat insulation layer formed by the self-leveling coating, forming a gradient heat absorption, and further significantly reducing the heat transfer to the room.

[0097] Detailed working principle:

[0098] During the day: The low thermal conductivity of the self-leveling emulsion-cured insulation layer 6 effectively blocks external heat from transferring inward. At this time, because the discretely distributed composite settling temperature-regulating particles 1 are located on the side away from the high-temperature external environment, the composite settling temperature-regulating particles 1 will not heat up immediately, thus delaying the phase change process. As time goes by, when the daytime temperature reaches its peak, the temperature of the self-leveling emulsion-cured insulation layer 6 close to the horizontal construction surface 7 of the roof (roof base surface) also slowly rises to the melting point of paraffin wax (usually designed at 28℃–50℃). At this time, the phase change paraffin 2 in the composite settling temperature regulating particles 1 close to the horizontal construction surface 7 (roof base surface) melts from solid to liquid, absorbing and storing a large amount of heat energy (latent heat); this process efficiently consumes excess heat on the building surface, significantly slows down the temperature rise of the building base surface, reduces the heat transfer to the room, and reduces air conditioning energy consumption; gradient heat absorption further significantly reduces the heat transfer to the room (experiments show that this near-base surface layer temperature regulation method improves the temperature regulation capability by >15% compared with the uniformly distributed phase change temperature regulating coating in the existing technology).

[0099] At night: When the ambient temperature drops below the solidification point of paraffin, the low thermal conductivity of the self-leveling emulsion-cured insulation layer 6 effectively blocks the heat transfer of the composite settling temperature-regulating particles 1 to the environment. At this time, because the discretely distributed composite settling temperature-regulating particles 1 are on the side away from the high-temperature environment, they will not cool down immediately, thus delaying the phase change heat release process. As time goes on, when the temperature reaches its lowest point at night, the temperature of the self-leveling emulsion-cured insulation layer 6 near the horizontal construction surface 7 (roof base surface) of the roof also slowly drops below the melting point of paraffin. At this time, the phase change paraffin 2 in the composite settling temperature-regulating particles 1 near the horizontal construction surface 7 (roof base surface) of the roof solidifies from liquid to solid, releasing a large amount of heat energy (latent heat). This process efficiently releases heat, significantly slowing down the cooling of the building base surface, while the self-leveling emulsion-cured insulation layer 6 delays the heat dissipation of the composite settling temperature-regulating particles 1.

[0100] The unique feature of this solution is that the phase change paraffin 2 is encapsulated within a hollow metal sphere 4 with a macroscopic structure. The contraction and expansion of the paraffin phase change process are completed within the robust hollow metal sphere 4, preventing compression and contraction of the self-leveling emulsion curing insulation layer 6. This eliminates the problem of coating cracking caused by the expansion and contraction of the phase change material during the phase change process. At the same time, the robust synergistic effect of the polyethylene encapsulation layer 5 and the hollow metal sphere 4 effectively prevents paraffin leakage, significantly improving the phase change cycle life in principle. Furthermore, the composite settling temperature regulating particles 1 are themselves a rigid structure that provides excellent support, thereby improving compressive strength.

[0101] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A self-leveling thermal insulation coating, characterized in that: Includes the following parts: Powder component A serves as the framework and reactive matrix of the self-leveling system; Component B of the emulsion serves as the reaction medium and flexible network of the self-leveling system; As a self-leveling system, gravity settles the composite settling temperature-regulating particles close to the base surface; Deionized water.

2. The self-leveling thermal insulation coating according to claim 1, characterized in that: The weight ratio of powder component A, emulsion component B, deionized water, and composite sedimentation temperature-regulating particles is 3:2:1:

2.

3. Further, the self-leveling heat-insulating coating according to claim 1, characterized in that: The powder component A includes: phosphogypsum-based cementitious material, cement, phosphogypsum waste powder, 50-60 mesh recycled glass fine aggregate, 80-150 mesh quartz sand, hemihydrate gypsum, lignin sulfonate water-reducing agent, polyacrylonitrile-based carbon fiber, hollow glass microspheres, and active crystallization components.

4. The self-leveling heat-insulating coating according to claim 1, characterized in that: The B component of the emulsion includes acrylate copolymer emulsion, silicone oil emulsion defoamer, organosilicon leveling agent, sodium gluconate, nano-SiO2 dispersion, and deionized water.

5. The self-leveling thermal insulation coating according to claim 1, characterized in that: Each single composite settling temperature-regulating particle is spherical in shape. It includes a hollow metal sphere with a negative pressure injection port. The hollow part inside the hollow metal sphere is filled with phase change paraffin wax. The outer surface of the hollow metal sphere is covered with a polyethylene encapsulation layer. The overall density of any single composite settling temperature-regulating particle is greater than the density of the liquid formed by mixing component A (powder), component B (emulsion), and deionized water.

6. A self-leveling heat-insulating coating, characterized in that: The composite thermal insulation coating includes a self-leveling emulsion-cured insulation layer. The portion of the self-leveling emulsion-cured insulation layer close to the horizontal construction surface of the roof has embedded composite settling temperature-regulating particles. Any single composite settling temperature-regulating particle includes a hollow metal sphere. The hollow metal sphere has a hollow negative pressure injection port. The hollow part inside the hollow metal sphere is filled with phase change paraffin wax. The outer surface of the hollow metal sphere is covered with a polyethylene encapsulation layer.

7. A preparation process for composite settling temperature-regulating particles of a self-leveling thermal insulation coating, characterized in that: Step 1: Mass-produce hollow metal spherical particles using molding and centrifugal spinning. Step 2: Using laser precision drilling, negative pressure injection ports are opened on each hollow metal sphere formed in "Step 1" in batches. Step 3: Place the batch of hollow metal spherical particles with negative pressure injection ports into a sealed container, and then use a vacuum negative pressure device to draw a vacuum into the sealed container. Shake the container appropriately so that the air inside each hollow metal spherical particle is discharged under the action of the vacuum environment, thereby making the interior of all the perforated hollow metal spherical particles in the container enter a vacuum state. Then slowly open the paraffin liquid injection valve at the bottom of the sealed container. Under the action of the vacuum negative pressure of the sealed container cavity, the molten paraffin is sucked into the bottom of the container vacuum cavity. Let the paraffin liquid level rise slowly and gradually completely submerge all the perforated hollow metal spheres. Keep the molten paraffin completely submerged in all the hollow metal spheres and maintain the vacuum state for a period of time of more than 15 minutes. The vacuum state inside the sealed container is slowly released. Under the action of vacuum negative pressure, the molten paraffin liquid is drawn into each vacuum-state hollow metal sphere through the negative pressure injection port, so that each hollow metal sphere is filled with paraffin liquid. Then drain the excess paraffin liquid from the container. After it is completely drained, a thin layer of paraffin will be attached to the surface of the metal spheres in the container. Place the hollow metal spheres filled with paraffin into an oven at a temperature higher than the melting point of paraffin, such as 70-80°C, and bake them so that the paraffin layer attached to the surface will melt and flow away. Step 3: The hollow metal spherical particles obtained in Step 3 are coated with polyethylene using a fluidized bed coating method to obtain the final composite sedimentation temperature-regulating particles.

8. A construction process for a self-leveling thermal insulation coating, characterized in that: S1, the emulsion composed of powder component A, emulsion component B, and deionized water is applied as a primer on the horizontal construction surface of the roof using a roller coating method; S2, after the primer coating is completed and the surface is dry for 3 hours, pour a predetermined amount of emulsion consisting of powder component A, emulsion component B, and deionized water into the enclosed construction surface; so that an uncured thick self-leveling thermal insulation coating is formed on the surface of the horizontal construction surface of the roof. S3 involves uniformly and discretely spreading composite settling temperature-regulating particles onto a thick self-leveling insulation coating. While maintaining uniform dispersion, accumulation is avoided. Under the influence of gravity, the composite settling temperature-regulating particles spread in the thick self-leveling insulation coating automatically sink to a position close to the horizontal construction surface of the roof.

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