Flame-retardant heat-preservation and heat-insulation double-coating structure for outer wall and manufacturing method of coating thereof

Abstract

The invention discloses a flame-retardant heat-preservation and heat-insulation double-coating structure for an outer wall and a manufacturing method of a coating of the flame-retardant heat-preservation and heat-insulation double-coating structure. The flame-retardant heat-preservation and heat-insulation double-coating structure comprises a heat-preservation and heat-insulation layer formed by coating a heat-preservation and heat-insulation coating and a reflective heat-insulation self-cleaning layer formed by coating the heat-preservation and heat-insulation coating The invention further discloses a manufacturing method of the coating of the flame-retardant heat-preservation and heat-insulation double-coating structure for the outer wall. The manufacturing method comprises a preparation step of the heat-preservation and heat-insulation coating and a preparation step of the reflective heat-insulation self-cleaning coating. According to the flame-retardant thermal-insulation double-coating structure for the outer wall and the manufacturing method of the coating of the flame-retardant thermal-insulation double-coating structure, the double-coating structure is adopted, the problem that flame retardance and thermal insulation are difficult to cooperate in the same coating is solved, the reflectivity, the thermal-insulation effect and the flame retardance of the coating structure can be effectively improved, meanwhile, the occurrence probability of microcracks is reduced, and the service life of the coating structure is prolonged. And the maintenance period of the heat insulation performance is ensured.

Description

Technical Field

[0001] This application relates to the field of coatings, specifically to a flame-retardant, thermally insulating double-coated structure for exterior walls and a method for manufacturing the coating thereon. Background Technology

[0002] To better meet people's needs, building exteriors are now generally coated to achieve effects such as heat insulation, heat insulation, or fire retardancy. However, traditional exterior coatings have the following problems:

[0003] (1) The reflectivity of the coating is only 55%-65%, and the overall reflectivity is low, which leads to the building surface temperature reaching 60℃-80℃ at its highest in summer;

[0004] (2) The thermal insulation coating adopts a single thermal insulation mechanism that relies solely on reflection or solely on aerogel insulation, which cannot simultaneously solve the three heat transfer modes of conduction, radiation and convection.

[0005] (3) Conflict between flame retardant performance and thermal insulation performance: ordinary flame retardants (such as aluminum hydroxide) will reduce the reflectivity of the coating, while high reflective fillers (such as titanium dioxide) lack the synergistic effect of flame retardancy.

[0006] (4) The temperature difference stress caused by the alternation of day and night causes microcracks to appear in traditional thermal insulation coatings during the service life, resulting in a thermal insulation performance degradation rate of >30% / year. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this application provides a method for manufacturing a flame-retardant, heat-insulating double-coat structure for exterior walls and its coating. The double-coat structure avoids the problem of difficulty in coordinating flame retardancy and heat insulation in the same coating, and can effectively improve the reflectivity, heat insulation effect and flame retardancy of the coating structure. At the same time, it reduces the probability of microcracks and ensures the maintenance life of its heat insulation performance.

[0008] The method for manufacturing flame-retardant, heat-insulating, and fire-resistant double-coated structure for exterior walls and its coating includes a heat-insulating layer made of heat-insulating coating and a reflective heat-insulating and self-cleaning layer made of reflective heat-insulating and self-cleaning coating applied to the heat-insulating layer.

[0009] Preferably, the thermal insulation layer comprises modified aerogel powder, hollow glass microspheres, and activated polyamide fibers.

[0010] The reflective heat-insulating self-cleaning layer comprises nano-slurry and surface-treated titanium dioxide.

[0011] The manufacturing method of a flame-retardant, heat-insulating, double-coated paint for exterior walls.

[0012] The preparation steps of the thermal insulation coating are as follows:

[0013] (A1) Raw material processing;

[0014] (A2) Mixing to prepare the base material;

[0015] (A3) After adding powder and fiber to the base material, filter to obtain thermal insulation coating;

[0016] The preparation steps of the reflective heat-insulating self-cleaning coating are as follows:

[0017] (B1) Raw material processing;

[0018] (B2) Base material composite;

[0019] (B3) Add auxiliary ingredients and cook;

[0020] (B4) After adjusting the viscosity, filter to obtain reflective heat-insulating self-cleaning coating.

[0021] The processing of raw materials in step (A1) includes:

[0022] (A1a) Surface modification of aerogel powder:

[0023] (A1a1) Preparation of silane coupling agent solution:

[0024] An ethanol solution was obtained by mixing ethanol and water in a volume ratio of 9:1.

[0025] Dissolve 0.5 parts by weight of KH-570 in 9.5 parts by weight of ethanol solution to obtain a mixture;

[0026] Acetic acid was added to adjust the pH of the mixture to 4.5, resulting in a silane coupling agent solution with a weight ratio of 1 part.

[0027] (A1a2) Weigh out 5-8 parts by weight of hydrophobic SiO2 aerogel powder with a pore size of 20-50 nm and a porosity of ≥90%.

[0028] (A1a3) Mix 5-8 parts by weight of hydrophobic SiO2 aerogel powder with 1 part by weight of silane coupling agent solution evenly, and then ultrasonically disperse at 40 kHz and 300 W for 30 min to obtain dispersion.

[0029] (A1a4) The dispersion was vacuum dried at 60℃ for 2h to obtain modified aerogel powder with a water content ≤1%.

[0030] (A1b) Screening of hollow glass microspheres:

[0031] The true density is taken as 0.20 ± 0.02 g / cm³. 3Borosilicate hollow microspheres were obtained, and particles with a particle size >80μm and <10μm were removed by air classifier sieve to obtain sieved hollow glass microspheres with a particle size in the range of 10-80μm.

[0032] (A1c) Polyamide fiber activation:

[0033] Polyamide 6 fibers with a length of 50-200 μm were placed in a plasma treatment machine and treated at 300 W for 5 min in an oxygen atmosphere to obtain activated polyamide fibers with a surface carboxyl density of 0.6-0.8 mmol / g.

[0034] The preparation method of the base material in step (A2) is as follows:

[0035] (A21) Add 20-25 parts by weight of styrene-acrylic flame retardant emulsion, 0.4 parts by weight of dispersant, and 0.2 parts by weight of defoamer to a stirred tank;

[0036] (A22) Start the mixing vessel and stir at 400 rpm for 10 minutes to ensure that the substances in the mixing vessel are mixed evenly and obtain the base material.

[0037] The specific preparation method for step (A3) is as follows:

[0038] (A31) Add the base material to a basket mill and slowly add modified aerogel powder and sieved hollow glass microspheres;

[0039] The weight ratio of the base material, modified aerogel powder, and sieved hollow glass microspheres is 2:1:0.8.

[0040] (A32) Start the basket mill and process it at 1200 rpm for 15 min to make the fineness of the mixture ≤50μm;

[0041] The zirconium beads used in the basket mill have a diameter of 1.0 mm;

[0042] (A33) Reduce the speed of the basket mill to 600 rpm, add 1 part by weight of activated polyamide fiber and treat for 15 min;

[0043] (A34) Fumed silica is gradually added to the basket mill as a thixotropic agent until the viscosity is adjusted to 95±5KU to obtain the initial material.

[0044] The viscosity of the initial material was measured by a rotational viscometer at a temperature of 25°C.

[0045] (A35) Pass the initial material through a 100-mesh sieve to remove undispersed lumps and obtain a thermal insulation coating.

[0046] The obtained thermal insulation coating needs to be sealed and stored at a temperature of 5-30℃.

[0047] The processing of raw materials in step (B1) includes:

[0048] (B1a) Pre-dispersion of nano-slurry:

[0049] Mix 6-8 parts by weight of silica sol with 6-8 parts by weight of near-infrared reflective powder Cs 0.33 WO3 was mixed and dispersed at high speed at 2000 rpm for 20 minutes, and then ground three times with a gap pressure of 0.4 MPa using a three-roll mill to obtain a nano slurry.

[0050] The SiO2 content in the silica sol is 30%.

[0051] (B1b) Titanium Dioxide Surface Treatment

[0052] 12-14 parts by weight of rutile titanium dioxide and 0.3 parts by weight of organosilicon dispersant were mixed and added to a ball mill. Zirconia balls were used to ball mill the mixture for 2 hours at a ball-to-material ratio of 2:1 to obtain surface-treated titanium dioxide.

[0053] The base material composite method in step (B2) is as follows:

[0054] (B21) Add 15-20 parts by weight of fluorocarbon modified acrylic emulsion, 0.5-1 parts by weight of nano slurry, 0.5-1 parts by weight of surface-treated titanium dioxide, and 0.3-0.5 parts by weight of photocatalytic nano TiO2 to the reactor in sequence.

[0055] (B22) Start the reactor and stir at 800 rpm for 30 minutes at a temperature ≤40℃ to obtain the composite base material.

[0056] The specific steps of step (B3) are as follows:

[0057] (B31) A flame-retardant mixture is obtained by mixing ammonium polyphosphate and melamine cyanurate in a mass ratio of 3:1.

[0058] (B32) While stirring, slowly add 1-2 parts by weight of flame retardant mixture and 0.2 parts by weight of leveling agent to 10-20 parts by weight of composite base material, and stir evenly to obtain the mixture;

[0059] (B33) Place the mixture in a sealed container and mature it at 25°C for 24 hours to obtain matured material.

[0060] The specific steps of step (B4) are as follows:

[0061] (B41) Adjust the viscosity of the cured material to 85-90 KU using a 2% hydroxyethyl cellulose solution;

[0062] (B42) Pass the conditioned material with adjusted viscosity through a 200-mesh sieve to obtain a reflective heat-insulating self-cleaning coating.

[0063] Compared with the prior art, the embodiments of this application have the following beneficial effects:

[0064] This invention employs a double-layer structure, which avoids the problem of flame retardancy and heat insulation being difficult to coordinate in the same coating. It can also effectively improve the reflectivity, heat insulation effect and flame retardancy of the coating structure, while reducing the probability of microcracks and ensuring the maintenance life of its heat insulation performance.

[0065] Some of the additional features of this application will be described in the following description. These additional features will become apparent to those skilled in the art upon examination of the following description and the accompanying drawings, or upon understanding the production or operation of the embodiments. The features disclosed in this application can be implemented and achieved through the practice or use of various methods, means, and combinations thereof with respect to the specific embodiments described below. Attached Figure Description

[0066] The accompanying drawings, which are provided to further illustrate this application and constitute a part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute a limitation thereof. In the drawings, the same reference numerals denote the same components.

[0067] Figure 1 This is a cross-sectional structural diagram of the present invention. Detailed Implementation

[0068] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0069] It should be noted that if the terms "first," "second," etc., are used in the specification, claims, and accompanying drawings of this application, they are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0070] In this application, when terms such as "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" are used, they indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are mainly for better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0071] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0072] Furthermore, in this application, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0073] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0074] Example 1

[0075] like Figure 1As shown, the flame-retardant thermal insulation double-coat structure for exterior walls and the method for manufacturing the coating thereof include a thermal insulation layer made of thermal insulation coating, and a reflective thermal insulation self-cleaning layer made of reflective thermal insulation self-cleaning coating applied on the thermal insulation layer.

[0076] The thermal insulation layer comprises modified aerogel powder, hollow glass microspheres, and activated polyamide fibers;

[0077] The reflective heat-insulating self-cleaning layer comprises nano-slurry and surface-treated titanium dioxide.

[0078] Example 2

[0079] The manufacturing method of a flame-retardant, heat-insulating, double-coated paint for exterior walls.

[0080] The preparation steps of the thermal insulation coating are as follows:

[0081] (A1) Raw material processing;

[0082] Raw material processing includes:

[0083] (A1a) Surface modification of aerogel powder:

[0084] (A1a1) Preparation of silane coupling agent solution:

[0085] An ethanol solution was obtained by mixing ethanol and water in a volume ratio of 9:1.

[0086] Dissolve 0.5 parts by weight of KH-570 in 9.5 parts by weight of ethanol solution to obtain a mixture;

[0087] Acetic acid was added to adjust the pH of the mixture to 4.5, resulting in a silane coupling agent solution with a weight ratio of 1 part.

[0088] (A1a2) Weigh out 5 parts by weight of hydrophobic SiO2 aerogel powder with a pore size of 20 nm and a porosity of ≥90%;

[0089] (A1a3) Mix 5 parts by weight of hydrophobic SiO2 aerogel powder with 1 part by weight of silane coupling agent solution evenly, and then ultrasonically disperse at 40 kHz and 300 W for 30 min to obtain dispersion.

[0090] (A1a4) The dispersion was vacuum dried at 60℃ for 2h to obtain modified aerogel powder with a water content ≤1%.

[0091] During the surface modification of the aerogel powder, the silane grafting rate was ≥80%, and the result was confirmed by FTIR analysis at 1720 cm⁻¹. -1 The peak area is tested according to the standard.

[0092] Modified aerogel powder, as a key component of the coating, has had its performance significantly improved in thermal insulation coatings through surface modification. Firstly, the compatibility of the aerogel powder treated with a silane coupling agent with the base material is greatly enhanced, strengthening the overall stability and adhesion of the coating. Secondly, the modified aerogel powder retains its high porosity (≥90%) and nanoscale pore size (20-50nm), which endow the coating with extremely low thermal conductivity, thus achieving excellent thermal insulation performance. Furthermore, the modification process enhances the hydrophobicity of the aerogel powder, enabling the coating to maintain high performance in humid environments and extending its service life. Compared with traditional insulation materials, this modified aerogel powder not only provides superior thermal insulation performance but also significantly improves the durability and environmental adaptability of the coating, demonstrating its innovation and technological advantages in the field of thermal insulation coatings.

[0093] (A1b) Screening of hollow glass microspheres:

[0094] The true density is taken as 0.20 ± 0.02 g / cm³. 3 Borosilicate hollow microspheres were obtained, and particles with a particle size >80μm and <10μm were removed by air classifier sieve to obtain sieved hollow glass microspheres with a particle size in the range of 10-80μm.

[0095] The breakage rate of the sieved hollow glass microspheres needs to be controlled to ≤5%. This parameter was obtained by centrifugation sedimentation at 3000 rpm for 10 minutes.

[0096] Hollow glass microspheres, due to their low density and hollow structure, can significantly reduce the density of coatings, making them lighter. Simultaneously, their uniform particle size distribution (10-80 μm) helps improve the thermal insulation performance and mechanical strength of the coating, enhancing its durability and crack resistance.

[0097] (A1c) Polyamide fiber activation:

[0098] Polyamide 6 fibers with a length of 50 μm were placed in a plasma treatment machine and treated with 300 W power for 5 min in an oxygen atmosphere to obtain activated polyamide fibers with a surface carboxyl density of 0.6 mmol / g.

[0099] The orientation deviation of the activated polyamide fiber distribution was ≤15°, obtained through statistical analysis of SEM images. The increased carboxyl group density on the surface of the activated polyamide fibers significantly improved their adhesion to the binder in the coating, enhancing the coating's adhesion and overall performance. Simultaneously, the addition of activated polyamide fibers improved the coating's toughness and impact resistance, making it less susceptible to damage from external physical impacts and extending its service life.

[0100] (A2) Mixing to prepare the base material;

[0101] The preparation method of the base material is as follows:

[0102] (A21) Add 20 parts by weight of styrene-acrylic flame retardant emulsion, 0.4 parts by weight of dispersant, and 0.2 parts by weight of defoamer to a stirred tank;

[0103] The styrene-acrylic flame retardant emulsion used is FR-828, the dispersant is BYK-190, and the defoamer is Foamex810.

[0104] (A22) Start the mixing vessel and stir at 400 rpm for 10 minutes to ensure that the substances in the mixing vessel are mixed evenly and obtain the base material.

[0105] As the fundamental component of thermal insulation coatings, the base material provides the necessary adhesion, stability, and mechanical strength, ensuring uniform adhesion of the coating to the wall surface. It also imparts basic protective and functional properties to the coating, such as flame retardancy and heat insulation, serving as a key carrier for achieving the coating's various performance characteristics. The addition of styrene-acrylic flame-retardant emulsion to the base material endows the coating with excellent flame-retardant properties, effectively reducing the risk of fire. Simultaneously, the synergistic effect of dispersants and defoamers ensures uniform mixing of the base material without internal bubble formation, resulting in a smooth and even coating surface that enhances both aesthetics and protective performance.

[0106] (A3) After adding powder and fiber to the base material, filter to obtain thermal insulation coating;

[0107] The specific preparation method is as follows:

[0108] (A31) Add the base material to a basket mill and slowly add modified aerogel powder and sieved hollow glass microspheres;

[0109] The weight ratio of the base material, modified aerogel powder, and sieved hollow glass microspheres is 2:1:0.8.

[0110] (A32) Start the basket mill and process it at 1200 rpm for 15 min to make the fineness of the mixture ≤50μm;

[0111] The zirconium beads used in the basket mill have a diameter of 1.0 mm;

[0112] (A33) Reduce the speed of the basket mill to 600 rpm, add 1 part by weight of activated polyamide fiber and treat for 15 min;

[0113] (A34) Fumed silica is gradually added to the basket mill as a thixotropic agent until the viscosity is adjusted to 95±5KU to obtain the initial material.

[0114] The viscosity of the initial material was measured by a rotational viscometer at a temperature of 25°C.

[0115] (A35) Pass the initial material through a 100-mesh sieve to remove undispersed lumps and obtain a thermal insulation coating.

[0116] The obtained thermal insulation coating needs to be sealed and stored at a temperature of 5-30℃.

[0117] The preparation steps of the reflective heat-insulating self-cleaning coating are as follows:

[0118] (B1) Raw material processing;

[0119] Raw material processing includes:

[0120] (B1a) Pre-dispersion of nano-slurry:

[0121] Six parts by weight of silica sol and six parts by weight of near-infrared reflective powder Cs were mixed. 0.33 WO3 was mixed and dispersed at high speed at 2000 rpm for 20 minutes, and then ground three times with a gap pressure of 0.4 MPa using a three-roll mill to obtain a nano slurry.

[0122] The SiO2 content in the silica sol is 30%.

[0123] Near-infrared reflective powder Cs 0.33 WO3 is a special functional material with highly efficient near-infrared (NIR) reflection capabilities. This chemical formula represents its crystal structure and composition.

[0124] Cs stands for cesium, an alkali metal, which is inserted as a dopant element into the tungsten bronze structure.

[0125] WO3, or tungsten trioxide, is the main framework material and has a unique crystal structure.

[0126] The subscript 0.33 indicates the doping ratio of cesium atoms in the crystal, that is, 0.33 cesium atoms are doped in each WO3 unit.

[0127] This leads to the formation of non-stoichiometric compounds, whose chemical formula can also be written as Cs. x WO3 (x≈0.33).

[0128] The purpose of pre-dispersing the nano-slurry is to fully mix the near-infrared reflective powder with the silica sol to form a uniform and stable dispersion system. This not only improves the reflective heat insulation performance of the coating and enhances its ability to reflect solar radiation heat, but also improves the coating's weather resistance and stability, ensuring that the coating maintains a high level of heat insulation performance during long-term use.

[0129] (B1b) Titanium Dioxide Surface Treatment

[0130] 12 parts by weight of rutile titanium dioxide and 0.3 parts by weight of organosilicon dispersant were mixed and added to a ball mill. Zirconia balls were used to ball mill the mixture for 2 hours at a ball-to-material ratio of 2:1 to obtain surface-treated titanium dioxide.

[0131] Among them, CR-828 is selected for rutile titanium dioxide and HDK-V15 is selected for organosilicon dispersant.

[0132] Ball milling allows the silicone dispersant to be uniformly coated on the surface of rutile titanium dioxide, significantly enhancing its dispersibility and stability in coating systems. This surface-treated rutile titanium dioxide can more effectively utilize its optical properties, improving coating whiteness and hiding power, while also enhancing weather resistance and anti-chalking properties, thus extending the coating's service life.

[0133] (B2) Base material composite;

[0134] The base material composite method is as follows:

[0135] (B21) 15 parts by weight of fluorocarbon modified acrylic emulsion, 0.5 parts by weight of nano slurry, 0.5 parts by weight of surface-treated titanium dioxide and 0.3 parts by weight of photocatalytic nano TiO2 were added to the reactor in sequence.

[0136] Among them, FL-2100 was selected for fluorocarbon modified acrylic emulsion, and titanium dioxide P25 was selected for photocatalytic nano-TiO2.

[0137] Fluorocarbon-modified acrylic emulsions provide the coating with excellent weather resistance and chemical corrosion resistance, enhancing its long-term stability. The synergistic effect of nano-slurry, surface-treated titanium dioxide, and photocatalytic nano-TiO2 not only improves the coating's reflective heat insulation performance but also endows it with good self-cleaning properties, enabling it to effectively resist the adhesion of stains and dust during long-term use and maintain a clean appearance.

[0138] (B22) Start the reactor and stir at 800 rpm for 30 minutes at a temperature ≤40℃ to obtain the composite base material.

[0139] (B3) Add auxiliary ingredients and cook;

[0140] The specific steps are as follows:

[0141] (B31) A flame-retardant mixture is obtained by mixing ammonium polyphosphate and melamine cyanurate in a mass ratio of 3:1.

[0142] (B32) While stirring, slowly add 1 part by weight of flame retardant mixture and 0.2 parts by weight of leveling agent to 10 parts by weight of composite base material, and stir evenly to obtain the mixture.

[0143] The leveling agent selected is BYK-333.

[0144] (B33) Place the mixture in a sealed container and mature it at 25°C for 24 hours to obtain matured material.

[0145] A flame-retardant mixture formed by mixing ammonium polyphosphate and melamine cyanurate in a 3:1 ratio imparts significant flame-retardant properties to the coating, effectively delaying the spread of fire and improving building fire safety. Adding this flame-retardant mixture and a leveling agent to the composite base followed by curing further enhances the uniformity and stability of the coating, ensuring a smooth and even surface after application and improving the overall quality and protective effect of the coating.

[0146] (B4) After adjusting the viscosity, filter to obtain a reflective heat-insulating self-cleaning coating;

[0147] The specific steps are as follows:

[0148] (B41) Adjust the viscosity of the cured material to 85-90 KU using a 2% hydroxyethyl cellulose solution;

[0149] The viscosity can be adjusted within the range of 85-90 KU by adjusting the amount of 2% hydroxyethyl cellulose solution added.

[0150] (B42) Pass the conditioned material with adjusted viscosity through a 200-mesh sieve to obtain a reflective heat-insulating self-cleaning coating.

[0151] By adjusting the viscosity of the curing agent to 85-90 KU using a 2% hydroxyethyl cellulose solution, the reflective heat-insulating self-cleaning coating is ensured to have good flowability and spreadability during construction, facilitating even application to the wall surface. Filtering through a 200-mesh sieve further removes impurities and undispersed particles from the coating, guaranteeing its fineness and construction quality. This results in a more stable performance and a smoother, more even appearance of the final reflective heat-insulating self-cleaning coating, effectively enhancing its heat insulation and self-cleaning effects.

[0152] The aforementioned thermal insulation coatings and reflective heat-insulating self-cleaning coatings can be applied in a double-layer structure or applied separately as a single coating layer.

[0153] The coating prepared in this embodiment is applied in a double-layer structure according to the method in Example 1, and its various properties are shown in Table 1 below:

[0154] Test Project result Solar reflectivity 82.5％ Vertical flammability rating UL94 V-0 (1.5mm thickness) thermal conductivity 0.038W / m·K Thermal cycling (-20℃~60℃) No cracking, adhesion ≥1.8MPa UV aging (1000h) Reflectivity attenuation ≤2% Salt spray test (500h) No bubbling or peeling Low temperature shock (-40℃) No cracks in the coating

[0155] Table 1

[0156] Example 3

[0157] The difference between this embodiment and Embodiment 2 is as follows:

[0158] In step (A1a2), the hydrophobic SiO2 aerogel powder has a weight of 8 parts and a pore size of 50 nm.

[0159] In step (A1a3), the weight of hydrophobic SiO2 aerogel powder is 8 parts.

[0160] In step (A1c), the length of the polyamide 6 fiber is 200 mm, and after treatment, activated polyamide fibers with a surface carboxyl density of 0.8 mmol / g are obtained.

[0161] In step (A21), the styrene-acrylic flame retardant emulsion is in the amount of 25 parts by weight.

[0162] In step (B1a), the silica sol comprises 7 parts by weight, and the near-infrared reflective powder Cs... 0.33 The weight of WO3 is 7 parts.

[0163] In step (B1b), the weight of rutile titanium dioxide is 14 parts.

[0164] In step (B21), the fluorocarbon modified acrylic emulsion is 20 parts by weight, the nano slurry is 0.7 parts by weight, the surface-treated titanium dioxide is 0.7 parts by weight, and the photocatalytic nano TiO2 is 0.5 parts by weight.

[0165] In step (B32), the weight parts of the base material are 15 parts and the weight parts of the flame retardant mixture are 2 parts.

[0166] Example 4

[0167] The difference between this embodiment and Embodiment 2 is as follows:

[0168] In step (A1a2), the hydrophobic SiO2 aerogel powder has a weight of 68 parts and a pore size of 35 nm.

[0169] In step (A1a3), the hydrophobic SiO2 aerogel powder is in the amount of 7 parts by weight.

[0170] In step (A1c), the length of the polyamide 6 fiber is 100, and after treatment, activated polyamide fibers with a surface carboxyl density of 0.7 mmol / g are obtained.

[0171] In step (A21), the styrene-acrylic flame retardant emulsion is in the amount of 22 parts by weight.

[0172] In step (B1a), the silica sol comprises 8 parts by weight, and the near-infrared reflective powder Cs... 0.33 The weight fraction of WO3 is 8 parts.

[0173] In step (B1b), the weight of rutile titanium dioxide is 13 parts.

[0174] In step (B21), the fluorocarbon modified acrylic emulsion is 17 parts by weight, the nano slurry is 1 part by weight, the surface-treated titanium dioxide is 1 part by weight, and the photocatalytic nano TiO2 is 0.4 parts by weight.

[0175] In step (B32), the weight percentage of the base material is 20 parts and the weight percentage of the flame retardant mixture is 1.5 parts.

[0176] It should be noted that all features disclosed in this specification, or all steps in all methods or processes disclosed, may be combined in any way, except for mutually exclusive features and / or steps.

[0177] Furthermore, the specific embodiments described above are exemplary. Those skilled in the art can devise various solutions inspired by the disclosure of this invention, and these solutions all fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification and its accompanying drawings are illustrative and not intended to limit the scope of the claims. The scope of protection of this invention is defined by the claims and their equivalents.

Claims

1. A flame-retardant, heat-insulating, double-coated structure for exterior walls, characterized in that: This includes a thermal insulation layer made of thermal insulation coating, and a reflective thermal insulation self-cleaning layer made of reflective thermal insulation self-cleaning coating applied to the thermal insulation layer.

2. The flame-retardant, heat-insulating, and fire-resistant double-coated structure for exterior walls according to claim 1, characterized in that, The thermal insulation layer comprises modified aerogel powder, hollow glass microspheres, and activated polyamide fibers; The reflective heat-insulating self-cleaning layer comprises nano-slurry and surface-treated titanium dioxide.

3. A method for manufacturing a coating based on the flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls as described in claim 1 or 2, characterized in that, The preparation steps of the thermal insulation coating are as follows: (A1) Raw material processing; (A2) Mixing to prepare the base material; (A3) After adding powder and fiber to the base material, filter to obtain thermal insulation coating; The preparation steps of the reflective heat-insulating self-cleaning coating are as follows: (B1) Raw material processing; (B2) Base material composite; (B3) Add auxiliary ingredients and cook; (B4) After adjusting the viscosity, filter to obtain reflective heat-insulating self-cleaning coating.

4. The flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating manufacturing method according to claim 3, characterized in that, The processing of raw materials in step (A1) includes: (A1a) Surface modification of aerogel powder: (A1a1) Preparation of silane coupling agent solution: An ethanol solution was obtained by mixing ethanol and water in a volume ratio of 9:

1. Dissolve 0.5 parts by weight of KH-570 in 9.5 parts by weight of ethanol solution to obtain a mixture; Acetic acid was added to adjust the pH of the mixture to 4.5, resulting in a silane coupling agent solution with a weight ratio of 1 part. (A1a2) Weigh out 5-8 parts by weight of hydrophobic SiO2 aerogel powder with a pore size of 20-50 nm and a porosity of ≥90%. (A1a3) Mix 5-8 parts by weight of hydrophobic SiO2 aerogel powder with 1 part by weight of silane coupling agent solution evenly, and then ultrasonically disperse at 40 kHz and 300 W for 30 min to obtain dispersion. (A1a4) The dispersion was vacuum dried at 60℃ for 2h to obtain modified aerogel powder with a water content ≤1%. (A1b) Screening of hollow glass microspheres: The true density is taken as 0.20 ± 0.02 g / cm³. 3 Borosilicate hollow microspheres were obtained, and particles with a particle size >80μm and <10μm were removed by air classifier sieve to obtain sieved hollow glass microspheres with a particle size in the range of 10-80μm. (A1c) Polyamide fiber activation: Polyamide 6 fibers with a length of 50-200 μm were placed in a plasma treatment machine and treated at 300 W for 5 min in an oxygen atmosphere to obtain activated polyamide fibers with a surface carboxyl density of 0.6-0.8 mmol / g.

5. The flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating manufacturing method according to claim 4, characterized in that, The preparation method of the base material in step (A2) is as follows: (A21) Add 20-25 parts by weight of styrene-acrylic flame retardant emulsion, 0.4 parts by weight of dispersant, and 0.2 parts by weight of defoamer to a stirred tank; (A22) Start the mixing vessel and stir at 400 rpm for 10 minutes to ensure that the substances in the mixing vessel are mixed evenly and obtain the base material.

6. The method for manufacturing the flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating as described in claim 5, characterized in that, The specific preparation method for step (A3) is as follows: (A31) Add the base material to a basket mill and slowly add modified aerogel powder and sieved hollow glass microspheres; The weight ratio of the base material, modified aerogel powder, and sieved hollow glass microspheres is 2:1:0.

8. (A32) Start the basket mill and process it at 1200 rpm for 15 min to make the fineness of the mixture ≤50μm; The zirconium beads used in the basket mill have a diameter of 1.0 mm; (A33) Reduce the speed of the basket mill to 600 rpm, add 1 part by weight of activated polyamide fiber and treat for 15 min; (A34) Fumed silica is gradually added to the basket mill as a thixotropic agent until the viscosity is adjusted to 95±5KU to obtain the initial material. The viscosity of the initial material was measured by a rotational viscometer at a temperature of 25°C. (A35) Pass the initial material through a 100-mesh sieve to remove undispersed lumps and obtain a thermal insulation coating. The obtained thermal insulation coating needs to be sealed and stored at a temperature of 5-30℃.

7. The flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating manufacturing method according to claim 3, characterized in that, The processing of raw materials in step (B1) includes: (B1a) Pre-dispersion of nano-slurry: Mix 6-8 parts by weight of silica sol with 6-8 parts by weight of near-infrared reflective powder Cs 0.33 WO3 was mixed and dispersed at high speed at 2000 rpm for 20 minutes, and then ground three times with a gap pressure of 0.4 MPa using a three-roll mill to obtain a nano slurry. The SiO2 content in the silica sol is 30%. (B1b) Titanium Dioxide Surface Treatment 12-14 parts by weight of rutile titanium dioxide and 0.3 parts by weight of organosilicon dispersant were mixed and added to a ball mill. Zirconia balls were used to ball mill the mixture for 2 hours at a ball-to-material ratio of 2:1 to obtain surface-treated titanium dioxide.

8. The flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating manufacturing method according to claim 7, characterized in that, The base material composite method in step (B2) is as follows: (B21) Add 15-20 parts by weight of fluorocarbon modified acrylic emulsion, 0.5-1 parts by weight of nano slurry, 0.5-1 parts by weight of surface-treated titanium dioxide, and 0.3-0.5 parts by weight of photocatalytic nano TiO2 to the reactor in sequence. (B22) Start the reactor and stir at 800 rpm for 30 minutes at a temperature ≤40℃ to obtain the composite base material.

9. The flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating manufacturing method according to claim 8, characterized in that, The specific steps of step (B3) are as follows: (B31) A flame-retardant mixture is obtained by mixing ammonium polyphosphate and melamine cyanurate in a mass ratio of 3:

1. (B32) While stirring, slowly add 1-2 parts by weight of flame retardant mixture and 0.2 parts by weight of leveling agent to 10-20 parts by weight of composite base material, and stir evenly to obtain the mixture; (B33) Place the mixture in a sealed container and mature it at 25°C for 24 hours to obtain matured material.

10. The flame-retardant, heat-insulating, and fire-resistant double-coating structure for exterior walls and its coating manufacturing method according to claim 9, characterized in that, The specific steps of step (B4) are as follows: (B41) Adjust the viscosity of the cured material to 85-90 KU using a 2% hydroxyethyl cellulose solution; (B42) Pass the conditioned material with adjusted viscosity through a 200-mesh sieve to obtain a reflective heat-insulating self-cleaning coating.

Images