Thermally-induced reversible color-changing temperature control coating based on hair structure microcapsules and preparation method of thermally-induced reversible color-changing temperature control coating

Abstract

The invention discloses a thermally-induced reversible color-changing temperature control coating based on hair structure microcapsules and a preparation method of the thermally-induced reversible color-changing temperature control coating. The thermochromic reversible temperature control coating is a double-layer structure temperature control coating composed of a high-reflection thermal insulation layer and a high-thermal-conductivity thermochromic layer, wherein the high-thermal-conductivity thermochromic layer is prepared by taking thermochromic reversible microcapsules with hair structures on the surfaces and nano silicon dioxide as composite fillers. On one hand, the hair fiber microcapsules have stronger dispersing performance, the microcapsule agglomeration phenomenon in the dispersing process is effectively avoided, and on the other hand, nano silicon dioxide particles are added in the surface fiber modification process and can be distributed among hairs of different particles, so that the heat conduction among the microcapsules can be effectively improved, and the heat conduction efficiency is improved. Therefore, the temperature change of the surface reversible color-changing layer is faster and more uniform, and the color-changing uniformity of the system is greatly improved. The coating is excellent in performance and has important significance on related technical progress and industrial development.

Description

Technical Field

[0001] The present invention belongs to the field of fine polymer materials, and particularly relates to the preparation of a thermally reversible color-changing temperature control coating based on hair structure microcapsules and its application in structural temperature control in the fields of transportation, construction, machinery, chemical engineering, etc. Background Art

[0002] For engineering structures serving in an exposed environment, solar radiation is the main external energy source, which will cause significant temperature fluctuations in the irradiated structures. Therefore, using temperature control materials with high reflectivity on the surface is one of the common measures to reduce the influence of solar radiation on the structure temperature and reduce the energy consumption of structural temperature control. However, this type of high-reflective temperature control material only has a cooling effect, and it will still have a reflective effect under conditions where the structure needs solar radiation to warm up in winter. This has an obvious side effect on the overall temperature control effect and energy consumption improvement, and significantly hinders the application prospect of this type of temperature control material in the western and northern regions of China. Therefore, developing intelligent temperature control materials with different surface photothermal properties in different scenarios has important economic and social significance, and also brings new development opportunities for the future application research of surface passive temperature control materials.

[0003] The photothermal properties of surface temperature control materials are closely related to their appearance color. Therefore, it is highly feasible to adjust the photothermal conversion properties of temperature control materials under different conditions by changing the appearance color. Among them, thermally reversible color-changing materials with temperature as the main color control element have become one of the important research objects. Among many thermochromic materials, powder microcapsules prepared based on a ternary organic reversible color-changing material system composed of pigments, developers, and solvents have become one of the current commercial mainstream products due to their sensitive color-changing reaction, narrow color-changing temperature range, large selectivity and adjustability of the color-changing temperature range and color, low price, and long service life. Currently, relevant researchers have used it as a pigment to prepare coatings with thermally reversible color-changing properties and have carried out certain applications in the fields of intelligent temperature control, temperature monitoring, thermal color anti-counterfeiting, temperature-changing clothing, etc.

[0004] A reversible thermochromic epoxy powder coating is disclosed in Patent CN117801627A. By adding thermosensitive color-changing pigments, the powder coating is made to have thermosensitive color-changing properties. After film formation, it has good leveling property, no pinholes, uniform color distribution, and the function of reversibly indicating temperature. A thermosensitive color-changing liquid crystal microcapsule ink and a color-changing coating are disclosed in Patent CN112980248B. By using cholesteric liquid crystal as the core material and polyurethane resin as the wall material, thermosensitive color-changing liquid crystal microcapsules are prepared, which can achieve color change between 40 - 65 °C for intuitive temperature measurement. A reversible color-changing coating is disclosed in Patent CN117050654A. By means of component ratio and screening, a color-changing coating with rich colors is prepared. It has high color-changing sensitivity, simple and convenient preparation process, good adhesion effect, and excellent coating effect, and is suitable for detecting the temperature of thermally induced defects of disconnector contacts. A negative-carbon and self-regulating temperature thermochromic coating is disclosed in Patent CN116285442B. By modifying the reversible color-changing microcapsules with titanium sol, its ultraviolet aging resistance is improved while the bonding force with the remaining inorganic carbonized cementitious materials is enhanced, and the coating has excellent performance.

[0005] From the above description, it can be seen that the currently existing thermally reversible color-changing coatings already have color-changing characteristics and certain practical value. However, in terms of the overall development of the technology, the thermally reversible color-changing coatings still face some problems. One is that in order to ensure good temperature control performance, the thermal conductivity of the coating is usually low, which leads to a large difference in the heating and cooling rates at different parts of the coating, and it is easy to appear patch phenomena during the color-changing process, affecting the aesthetics and practical effects. Secondly, the dispersion of the color-changing microcapsules is usually difficult. It is difficult to disperse them evenly under low-speed conditions, while under high-speed conditions, the microcapsules may be broken and leaked, causing difficulties in coating production. Moreover, the cost of the microcapsules is usually high and the dosage is also large, resulting in a substantial increase in the coating cost and making it difficult to promote and apply. Therefore, based on relevant research, further developing new thermally reversible color-changing coatings, improving the system dispersion uniformity and appearance color-changing uniformity of the coatings, enhancing the color-changing and color-developing ability, and reducing the preparation cost are of great significance for promoting the further development of related technologies and the progress of the industry. Summary of the Invention

[0006] The object of the present invention is to solve the above problems and provide a thermally reversible color-changing temperature control coating based on hair structure microcapsules and its preparation method.

[0007] The thermally reversible color-changing temperature control coating based on hair structure microcapsules described in the present invention is a double-layer structure temperature control coating composed of a high-reflection heat insulation layer and a high-thermal-conductivity thermochromic layer; the high-reflection heat insulation layer is prepared from a high-performance reflective heat insulation coating filled with rutile titanium dioxide and hollow glass microspheres; the high-thermal-conductivity thermochromic layer is prepared from a high-thermal-conductivity thermally reversible color-changing coating filled with thermally reversible color-changing microcapsules with hair structures on the surface and nano-silica; the dry film thicknesses of the high-reflection heat insulation layer and the high-thermal-conductivity thermochromic layer are 80-120 μm and 30-50 μm respectively.

[0008] The high-thermal-conductivity thermally reversible color-changing coating in the thermally reversible color-changing temperature control coating is composed of a component A1 main agent and a component B1 curing agent. The component A1 main agent is prepared from a matrix resin, a composite filler of hair structure microcapsules and nano-silica, a solvent, a functional auxiliary agent and a rheology regulator. The component B curing agent is prepared from a curing agent and a solvent; the mass ratio of the hair structure microcapsules and nano-silica in the composite filler is 1:(0.3-0.6); the mass ratio of the component A1 main agent and the component B curing agent is 1:(0.08-0.22).

[0009] The preparation method of the filler in the high-thermal-conductivity thermally reversible color-changing coating comprises the following steps: (1) Dissolve the ternary thermally reversible color-changing core material composed of a pigment, a color developer and a solvent, add it to deionized water containing an emulsifier, and perform high-speed emulsification under heating conditions at 65 °C to obtain a thermally reversible color-changing emulsion; (2) Drop the resin prepolymer into the reversible color-changing emulsion at a constant speed under heating and stirring conditions. After the dropping is completed, perform in-situ polymerization at 85 °C for 1 h. Filter and dry the reaction suspension to obtain thermally reversible color-changing microcapsules; (3) Mix and dissolve N,N-methylenebisacrylamide, ethanol, toluene, a RAFT reagent and an initiator completely. Add the reversible color-changing microcapsules and nano-silica to it and disperse them evenly by high-speed stirring. Perform in-situ RAFT precipitation polymerization in a nitrogen environment at 80 °C for 24 h, and then filter and dry to obtain a mixed filler of reversible color-changing microcapsules with nano-hair structures on the surface and nano-silica.

[0010] In this preparation method, the pigment is at least one of crystal violet lactone, 2-phenylamino-3-methyl-6-dibutylaminofluorane, and 3',6'-dimethoxyfluorane; the developer is at least one of bisphenol A, bisphenol F, and bisphenol S; the solvent is at least one of tetradecanol, glyceryl tricaprate, methyl stearate, and ethyl stearate; wherein the mass concentration of the pigment molecules is 0.8 - 6%, and the mass ratio of the pigment to the developer is 1:(1.5 - 4); the emulsifier is at least one of sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium salt of styrene maleic anhydride copolymer, and its mass concentration is 0.5 - 1%; the resin prepolymer is at least one of melamine resin prepolymer, urea-formaldehyde resin prepolymer, methylmelamine formaldehyde resin prepolymer, polyurethane resin prepolymer, and acrylic resin, and the dosage is 5 - 13% of the total amount.

[0011] In this preparation method, the mass concentration of N,N-methylenebisacrylamide is 0.5 - 1.5%, the mass concentration of ethanol is 1.5 - 3%, the RAFT reagent is at least one of dithiobenzoate, trithiocarbonate, and dithiocarbamate, and its dosage is 8 - 12% of the monomer amount; the initiator is at least one of azobisisobutyronitrile, azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, and lauroyl peroxide, and its dosage is 1 - 2% of the monomer amount.

[0012] The high-performance reflective heat-insulating coating in this thermally induced reversible color-changing temperature control coating is composed of an A2 component main agent and a B component curing agent. Among them, the A2 component main agent is prepared from a matrix resin, rutile titanium dioxide, hollow glass microspheres, a solvent, functional additives, and a rheology regulator; among them, the mass ratio of the rutile titanium dioxide to the hollow glass microspheres is 1:(0.8 - 1.2); among them, the mass ratio of the A2 component main agent to the B component curing agent is 1:(0.08 - 0.22).

[0013] In the main agent components of the two coatings in this thermally induced reversible color-changing temperature control coating, the contents of the matrix resin, filler, solvent, functional additives, and rheology regulator are 50 - 72%, 22 - 33%, 3 - 10%, 0.5 - 3.5%, and 0.5 - 2.0% respectively, based on the total mass of the main agent; among them, the matrix resin is at least one of silicone resin, fluorocarbon resin, polyurethane resin, and acrylic-modified polyurethane resin; among them, the solvent is at least one of xylene, methyl ethyl ketone, n-butanol, butyl acetate, dimethylformamide, propylene glycol methyl ether acetate, and water; among them, the functional additives are at least one of a dispersant, an antifoaming agent, a leveling agent, and an adhesion promoter; among them, the rheology regulator is at least one of bentonite, magnesium silicate hydrate, fumed silica, and polymer wax.

[0014] In the B-component curing agent of the two coatings in the thermally induced reversible color-changing temperature control coating, the contents of isocyanate and solvent are 85%-100% and 0-15% respectively, based on the total mass of the B-component; wherein the isocyanate is at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane dimethylene diisocyanate, benzene dimethylene diisocyanate, hydrophilic HDI polyisocyanate, polymethylene polyphenyl polyisocyanate, hexamethylene diisocyanate trimer and hexamethylene diisocyanate biuret; the solvent is at least one of xylene, methyl ethyl ketone, n-butanol, butyl acetate, dimethylformamide, propylene glycol methyl ether acetate and water.

[0015] The preparation method of the two coatings in the thermally induced reversible color-changing temperature control coating comprises the following steps: (1) Weigh appropriate masses of each component, disperse and mix the matrix resin and filler using a high-speed disperser at a linear velocity of 40-60 °C and 6-10 m / s for 15 min, then perform ultrasonic treatment for 4-10 min, and then add the remaining components to the mixture and disperse for 30 min until the system is homogeneous and stable to obtain the main component of the coating; (2) Disperse and mix the isocyanate and solvent using a high-speed disperser for 15 min until the system is homogeneous and stable to obtain the curing agent component.

[0016] The on-site construction method of the two coatings in the thermally induced reversible color-changing temperature control coating can be any one of spraying, dipping, roll coating and brushing.

[0017] The positive effects of a thermally induced reversible color-changing temperature control coating based on hair structure microcapsules of the present invention are: The thermally induced reversible color-changing temperature control coating prepared in the present invention is realized through a double-layer structure. The bottom high-reflection heat-insulating layer has extremely strong reflection and heat-insulating properties. The surface thermally induced reversible color-changing layer is colorless and transparent at high temperatures, which can fully reflect the reflection and heat-insulating properties of the bottom layer, while it is black under low-temperature conditions, covering the bottom coating and having heat absorption and heat preservation properties. Compared with traditional thermochromic coatings, the double-layer design reduces the usage amount of reversible color-changing materials, greatly improves the color-changing ability and temperature control effect of the system, and has excellent technical economy.

[0018] Moreover, in the surface thermally induced reversible color-changing layer, hair-like nanofibers are surface-modified on the basis of traditional spherical microcapsules through RAFT precipitation polymerization. On the one hand, it has stronger dispersion performance, effectively avoiding the aggregation phenomenon of microcapsules during the dispersion process. On the other hand, due to the addition of nano-silica particles during the surface modification process, they will be distributed between the hairs of different particles, which can effectively improve the heat conduction between microcapsules, making the temperature change of the surface reversible color-changing layer faster and more uniform, and greatly improving the color-changing uniformity of the system.

[0019] As can be seen from the above description, the action mechanism of the thermally induced reversible color-changing coating technology is clear, the production process is simple, the product has excellent performance, strong durability, low cost, and is suitable for large-scale production applications. It is of great significance for the preparation and research and development of surface passive temperature control materials with intelligent temperature control functions and their promotion in related application fields. Brief Description of the Drawings

[0020] Figure 1 It is a scanning electron microscope image of thermally induced reversible color-changing microcapsules with a hair fiber structure on the surface. Detailed Description of the Invention

[0021] The present invention will be further described in detail below with specific embodiments.

[0022] Example 1: A thermally induced reversible color-changing temperature control coating A based on microcapsules with a hair structure, and its preparation process is as follows: (1) Under heating conditions, 3.5 parts of crystal violet lactone, 7 parts of bisphenol A, and 89.5 parts of myristyl alcohol are completely dissolved to form a clear ternary color-changing system oil phase. The oil phase is added to water containing 0.8% sodium dodecyl sulfate at 65 °C to prepare a thermally induced reversible color-changing emulsion. Then, 8 parts of melamine resin prepolymer are dropwise added to the emulsion under heating conditions, and in-situ polymerization is carried out at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally induced reversible color-changing microcapsules a1 can be obtained.

[0023] (2) 1.5 parts of N,N'-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 part of trithiocarbonate, and 0.035 part of azobisisobutyronitrile are mixed evenly under ultrasonic conditions and completely dissolved at 80 °C. 20 parts of thermally induced reversible color-changing microcapsules a1 and 10 parts of nano-silica particles are added thereto and dispersed evenly by high-speed stirring. After in-situ RAFT precipitation polymerization for 24 h in a nitrogen environment at 80 °C, filtration and drying are carried out to obtain a mixed filler a of reversible color-changing microcapsules with a nano-hair structure on the surface and nano-silica.

[0024] (3) Weigh 57 parts of fluorocarbon resin, 9 parts of xylene, 28 parts of mixed filler a, 0.5 part of dispersant, 0.5 part of leveling agent, 0.6 part of defoaming agent, and 0.9 part of magnesium hydrosilicate. The fluorocarbon resin and the mixed filler a are dispersed and mixed using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then, the remaining components are added to the mixture and dispersed for 30 min until the system is uniform and stable to obtain the main component Aa1 of the high thermal conductivity thermally induced reversible color-changing coating.

[0025] (4) Disperse and mix 30 parts of toluene diisocyanate, 65 parts of toluene diisocyanate trimer, and 5 parts of xylene using a high-speed disperser for 15 min until the system is homogeneous and stable, then the curing agent component Ab1 of the high thermal conductivity thermally reversible color-changing coating can be obtained.

[0026] (5) Weigh 62 parts of polyurethane resin, 7.3 parts of propylene glycol methyl ether acetate, 15 parts of rutile titanium dioxide, 13 parts of hollow glass microspheres, 0.4 part of dispersant, 0.4 part of leveling agent, 0.5 part of defoamer, and 1.35 parts of fumed silica. Disperse and mix the polyurethane resin, rutile titanium dioxide, and hollow glass microspheres using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, then perform ultrasonic treatment for 4 - 10 min. Then add the remaining components to the mixture and disperse for 30 min until the system is homogeneous and stable to obtain the main agent component Aa2 of the high-reflection heat-insulating coating.

[0027] (6) Disperse and mix 30 parts of toluene diisocyanate, 65 parts of toluene diisocyanate trimer, and 5 parts of propylene glycol methyl ether acetate using a high-speed disperser for 15 min until the system is homogeneous and stable, then the curing agent component Ab2 can be obtained.

[0028] (7) Weigh the main agent Aa2 and the curing agent Ab2 according to a mass ratio of 1:0.13, mix them evenly using mechanical stirring, and then prepare a high-reflection heat-insulating layer with a dry film thickness of 100 μm by spraying construction.

[0029] (8) Weigh the main agent Aa1 and the curing agent Ab1 according to a mass ratio of 1:0.15, mix them evenly using mechanical stirring, and after the high-reflection heat-insulating layer is dried, prepare a high thermal conductivity thermally reversible color-changing layer with a dry film thickness of 40 μm by spraying construction, then the thermally reversible color-changing temperature control coating A with a double-layer structure can be obtained.

[0030] Example 2: A thermally reversible color-changing temperature control coating B based on hair structure microcapsules, and its preparation process is as follows: (1) Under heating conditions, dissolve 2.5 parts of 2-anilino-3-methyl-6-dibutylamino fluorane, 5.5 parts of bisphenol S, and 92 parts of glyceryl tridecanoate completely to form a clear ternary color-changing system oil phase. Add the oil phase to water containing 0.9% sodium salt of styrene maleic anhydride copolymer at 65 °C to prepare a thermally reversible color-changing emulsion. Then drop 12 parts of urea formaldehyde resin prepolymer into the emulsion under heating conditions and perform in-situ polymerization at 85 °C for 1 h. After filtering and drying the reaction suspension, the thermally reversible color-changing microcapsules b1 can be obtained.

[0031] (2) 1.5 parts of N,N - methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 parts of trithiocarbonate and 0.035 parts of azobisisobutyronitrile were mixed evenly under ultrasonic conditions and dissolved completely at 80 °C. 20 parts of thermally reversible color - changing microcapsules b1 and 8 parts of nano - silica particles were added thereto and dispersed evenly by high - speed stirring. After in - situ RAFT precipitation polymerization for 24 h in a nitrogen environment at 80 °C, filtration and drying were carried out to obtain a mixed filler b of reversible color - changing microcapsules with a nano - hair structure on the surface and nano - silica.

[0032] (3) 65 parts of water - borne polyurethane resin, 7 parts of water, 24 parts of mixed filler b, 0.5 parts of dispersant, 0.4 parts of defoamer and 0.6 parts of fumed silica were weighed. The water - borne polyurethane resin and the mixed filler b were dispersed and mixed using a high - speed disperser under the conditions of 40 - 60 °C and a linear velocity of 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then the remaining components were added to the mixture and dispersed for 30 min until the system was uniform and stable to obtain the main component Ba1 of the high - thermal - conductivity thermally reversible color - changing coating.

[0033] (4) Hydrophilic HDI polyisocyanate was used as the curing agent component Bb1 of the high - thermal - conductivity thermally reversible color - changing coating.

[0034] (5) The preparation process of the main component Aa2 and the curing agent component Ab2 of the high - reflective heat - insulating coating was as in Example 1.

[0035] (6) The main agent Aa2 and the curing agent Ab2 were weighed according to a mass ratio of 1:0.13, mixed evenly by mechanical stirring, and a high - reflective heat - insulating layer with a dry film thickness of 100 μm was prepared by spraying construction.

[0036] (7) The main agent Ba1 and the curing agent Bb1 were weighed according to a mass ratio of 1:0.11, mixed evenly by mechanical stirring, and a high - thermal - conductivity thermally reversible color - changing layer with a dry film thickness of 40 μm was prepared by spraying construction after the high - reflective heat - insulating layer was dried, thus obtaining the thermally reversible color - changing temperature - controlling coating B with a double - layer structure.

[0037] Example 3: A thermally reversible color - changing temperature - controlling coating C based on microcapsules with a hair structure, and its preparation process is as follows: (1) Under heating conditions, 3.2 parts of crystal violet lactone, 8 parts of bisphenol F and 88.8 parts of methyl stearate were dissolved completely to form a clear ternary color - changing system oil phase. The oil phase was added to water containing 0.75% sodium dodecyl sulfate at 65 °C to prepare a thermally reversible color - changing emulsion. Then 8.4 parts of methylated melamine - formaldehyde resin prepolymer were added dropwise into the emulsion under heating conditions and in - situ polymerized at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally reversible color - changing microcapsules c1 were obtained.

[0038] (2) 1.5 parts of N,N-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 part of trithiocarbonate and 0.035 part of azobisisobutyronitrile were mixed evenly under ultrasonic conditions and completely dissolved at 80 °C. 20 parts of thermally reversible color-changing microcapsules c1 and 9 parts of nano-silica particles were added thereto and dispersed evenly by high-speed stirring. After in-situ RAFT precipitation polymerization for 24 h in a nitrogen environment at 80 °C, filtration and drying were carried out to obtain a mixed filler c of reversible color-changing microcapsules with a nano-hair structure on the surface and nano-silica.

[0039] (3) 55 parts of fluorocarbon resin, 8.5 parts of acetone, 29 parts of mixed filler c, 1 part of dispersant, 1 part of leveling agent, 1 part of defoaming agent and 1.3 parts of bentonite were weighed. The fluorocarbon resin and the mixed filler c were dispersed and mixed for 15 min under the conditions of 40-60 °C and a linear velocity of 6-10 m / s using a high-speed disperser, followed by ultrasonic treatment for 4-10 min. Then the remaining components were added to the mixture and dispersed for 30 min until the system was uniform and stable to obtain the main component Ca1 of the high thermal conductivity thermally reversible color-changing coating.

[0040] (4) 85 parts of isophorone diisocyanate and 15 parts of acetone were dispersed and mixed for 15 min using a high-speed disperser until the system was uniform and stable to obtain the curing agent component Cb1 of the high thermal conductivity thermally reversible color-changing coating.

[0041] (5) The preparation process of the main component Aa2 and the curing agent component Ab2 of the high-reflection heat-insulating coating was as in Example 1.

[0042] (6) The main component Aa2 and the curing agent Ab2 were weighed according to a mass ratio of 1:0.13, mixed evenly by mechanical stirring, and a high-reflection heat-insulating layer with a dry film thickness of 100 μm was prepared by spraying construction.

[0043] (7) The main component Ca1 and the curing agent Cb1 were weighed according to a mass ratio of 1:0.12, mixed evenly by mechanical stirring, and a high thermal conductivity thermally reversible color-changing layer with a dry film thickness of 40 μm was prepared by spraying construction after the high-reflection heat-insulating layer was dried, thus obtaining the thermally reversible color-changing temperature control coating C with a double-layer structure.

[0044] Example 4: A thermally reversible color-changing temperature control coating D based on microcapsules with a hair structure, and its preparation process is as follows: (1) Under heating conditions, 2.2 parts of 3',6'-dimethoxy fluoran, 3.5 parts of bisphenol S, and 94.3 parts of myristyl alcohol were completely dissolved to form a clear ternary color-changing system oil phase. The oil phase was added to water containing 0.9% sodium dodecylbenzenesulfonate at 65 °C to prepare a thermally reversible color-changing emulsion. Then, 11 parts of melamine resin prepolymer were dropwise added to the emulsion under heating conditions and in-situ polymerized at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally reversible color-changing microcapsules d1 were obtained.

[0045] (2) 1.5 parts of N,N-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 parts of trithiocarbonate, and 0.035 parts of azobisisobutyronitrile were mixed evenly under ultrasonic conditions and completely dissolved at 80 °C. 20 parts of thermally reversible color-changing microcapsules d1 and 10 parts of nano-silica particles were added thereto and dispersed evenly by high-speed stirring. After in-situ RAFT precipitation polymerization for 24 h in a nitrogen environment at 80 °C, filtration and drying were carried out to obtain a mixed filler d of reversible color-changing microcapsules with a nano-hair structure on the surface and nano-silica.

[0046] (3) Weigh 60 parts of waterborne fluorocarbon resin, 5.6 parts of water, 30 parts of mixed filler c, 0.6 parts of dispersant, 0.6 parts of leveling agent, and 1 part of polymer wax. The waterborne fluorocarbon resin and mixed filler d were dispersed and mixed using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then, the remaining components were added to the mixture and dispersed for 30 min until the system was uniform and stable to obtain the main component Da1 of the high thermal conductivity thermally reversible color-changing coating.

[0047] (4) Hydrophilic HDI polyisocyanate was used as the curing agent component Db1 of the high thermal conductivity thermally reversible color-changing coating.

[0048] (5) The preparation process of the main component Aa2 and curing agent component Ab2 of the high-reflection heat-insulating coating was as in Example 1.

[0049] (6) Weigh the Aa2 main agent and Ab2 curing agent according to a mass ratio of 1:0.13, mix them evenly using mechanical stirring, and prepare a high-reflection heat-insulating layer with a dry film thickness of 100 μm by spraying construction.

[0050] (7) Weigh the Da1 main agent and Db1 curing agent according to a mass ratio of 1:0.15, mix them evenly using mechanical stirring, and prepare a high thermal conductivity thermally reversible color-changing layer with a dry film thickness of 40 μm by spraying construction after the high-reflection heat-insulating layer is dried, thus obtaining a thermally reversible color-changing temperature control coating D with a double-layer structure.

[0051] Example 5: A thermally reversible color-changing temperature control coating E based on microcapsules with a hair structure, and its preparation process is as follows: (1) Under heating conditions, 4 parts of 2-phenylamino-3-methyl-6-dibutylaminofluorane, 8 parts of bisphenol A, and 88 parts of methyl stearate are completely dissolved to form a clear ternary color-changing system oil phase. The oil phase is added to water containing 0.7% sodium salt of styrene maleic anhydride copolymer at 65 °C to prepare a thermally reversible color-changing emulsion. Then, 10 parts of methylated melamine formaldehyde resin prepolymer are dropwise added to the emulsion under heating conditions and in-situ polymerized at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally reversible color-changing microcapsules e1 can be obtained.

[0052] (2) 1.5 parts of N,N-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 part of trithiocarbonate, and 0.035 part of azobisisobutyronitrile are mixed evenly under ultrasonic conditions and completely dissolved at 80 °C. 20 parts of thermally reversible color-changing microcapsules e1 and 11 parts of nano-silica particles are added thereto and dispersed evenly by high-speed stirring. After in-situ RAFT precipitation polymerization for 24 h in a nitrogen environment at 80 °C, filtration and drying are carried out to obtain a mixed filler e of reversible color-changing microcapsules with nano-hair structures on the surface and nano-silica.

[0053] (3) Weigh 58 parts of silicone resin, 9 parts of butyl acetate, 27 parts of mixed filler e, 0.6 part of leveling agent, and 0.6 part of defoaming agent. The silicone resin and the mixed filler e are dispersed and mixed using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then, the remaining components are added to the mixture and dispersed for 30 min until the system is homogeneous and stable to obtain the main component Ea1 of the high thermal conductivity thermally reversible color-changing coating.

[0054] (4) 60 parts of dicyclohexylmethane diisocyanate, 35 parts of hexamethylene diisocyanate biuret, and 5 parts of butyl acetate are dispersed and mixed using a high-speed disperser for 15 min until the system is homogeneous and stable to obtain the curing agent component Eb1 of the high thermal conductivity thermally reversible color-changing coating.

[0055] (5) The preparation process of the main component Aa2 and the curing agent component Ab2 of the high-reflection heat-insulating coating is as in Example 1.

[0056] (6) Weigh the main agent Aa2 and the curing agent Ab2 according to a mass ratio of 1:0.13, mix them evenly using mechanical stirring, and prepare a high-reflection heat-insulating layer with a dry film thickness of 100 μm by spraying construction.

[0057] (7) Weigh the main agent Ea1 and the curing agent Eb1 according to a mass ratio of 1:0.09, mix them evenly using mechanical stirring, and prepare a high thermal conductivity thermally reversible color-changing layer with a dry film thickness of 40 μm by spraying construction after the high-reflection heat-insulating layer is dried, thereby obtaining a thermally reversible color-changing temperature control coating E with a double-layer structure.

[0058] Example 6: A thermally reversible color-changing temperature control coating F based on hair structure microcapsules is prepared as follows: (1) Under heating conditions, 5.4 parts of crystal violet lactone, 10 parts of bisphenol F, and 84.6 parts of glyceryl tricaprate are completely dissolved to form a clear ternary color-changing system oil phase. The oil phase is added to water containing 0.8% sodium dodecylbenzenesulfonate at 65 °C to prepare a thermally reversible color-changing emulsion. Then, 7.5 parts of phenolic resin prepolymer are added dropwise to the emulsion under heating conditions and in-situ polymerized at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally reversible color-changing microcapsules f1 can be obtained.

[0059] (2) 1.5 parts of N,N'-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 parts of trithiocarbonate, and 0.035 parts of azobisisobutyronitrile are mixed evenly under ultrasonic conditions and completely dissolved at 80 °C. 20 parts of thermally reversible color-changing microcapsules f1 and 10 parts of nano-silica particles are added thereto and dispersed evenly by high-speed stirring. After in-situ RAFT precipitation polymerization in a nitrogen environment at 80 °C for 24 h, filtration and drying are carried out to obtain a reversible color-changing microcapsule with a nano-hair structure on the surface and a nano-silica mixed filler f.

[0060] (3) Weigh 63 parts of polyurethane resin, 3.2 parts of propylene glycol methyl ether acetate, 25 parts of mixed filler f, 1 part of leveling agent, and 1 part of adhesion promoter. The polyurethane resin and the mixed filler f are dispersed and mixed using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then, the remaining components are added to the mixture and dispersed for 30 min until the system is homogeneous and stable to obtain the main component Fa1 of the high thermal conductivity thermally reversible color-changing coating.

[0061] (4) 93 parts of cyclohexane diisocyanate and 7 parts of propylene glycol methyl ether acetate are dispersed and mixed using a high-speed disperser for 15 min until the system is homogeneous and stable to obtain the curing agent component Fb1 of the high thermal conductivity thermally reversible color-changing coating.

[0062] (5) The preparation process of the main component Aa2 and the curing agent component Ab2 of the high-reflection heat-insulating coating is as in Example 1.

[0063] (6) Weigh the main component Aa2 and the curing agent Ab2 according to a mass ratio of 1:0.13, mix them evenly using mechanical stirring, and prepare a high-reflection heat-insulating layer with a dry film thickness of 100 μm by spraying construction.

[0064] (7) Weigh the main agent Fa1 and the curing agent Fb1 according to the mass ratio of 1:0.09. After mixing them evenly by mechanical stirring, spray them on the dried high-reflectivity heat-insulating layer to prepare a high-thermal-conductivity thermally reversible color-changing layer with a dry film thickness of 40 μm, and then the thermally reversible color-changing temperature-control coating F with a double-layer structure can be obtained.

[0065] Comparative Example 1: Commercially available thermochromic pigment Take a commercially available thermochromic coating of a certain brand to prepare a thermochromic coating and compare its performance with that of the examples.

[0066] Comparative Example 2: Preparation of a coating with conventional thermochromic microcapsules. The preparation process is as follows: (1) Under heating conditions, dissolve 3.2 parts of crystal violet lactone, 8 parts of bisphenol F, and 88.8 parts of methyl stearate completely to form a clear ternary color-changing system oil phase. Add the oil phase to water containing 0.75% sodium dodecyl sulfate at 65 °C to prepare a thermally reversible color-changing emulsion. Then, drop 8.4 parts of methylated melamine formaldehyde resin prepolymer into the emulsion under heating conditions and carry out in-situ polymerization at 85 °C for 1 h. After filtering and drying the reaction suspension, the thermally reversible color-changing microcapsules c1 can be obtained.

[0067] (2) Weigh 55 parts of fluorocarbon resin, 8.5 parts of acetone, 20 parts of thermally reversible color-changing microcapsules c1, 1 part of dispersant, 1 part of leveling agent, 1 part of defoaming agent, and 1.3 parts of bentonite. Disperse and mix the fluorocarbon resin and the thermally reversible color-changing microcapsules c1 with a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, and then carry out ultrasonic treatment for 4 - 10 min. Then add the remaining components to the mixture and disperse for 30 min to obtain the main agent component Ga1 of the thermally reversible color-changing coating.

[0068] (3) Disperse and mix 85 parts of isophorone diisocyanate and 15 parts of acetone with a high-speed disperser for 15 min until the system is homogeneous and stable, and then the curing agent component Gb1 of the high-thermal-conductivity thermally reversible color-changing coating can be obtained.

[0069] (4) The preparation processes of the main agent component Aa2 and the curing agent component Ab2 of the high-reflectivity heat-insulating coating are as in Example 1.

[0070] (5) Weigh the main agent Aa2 and the curing agent Ab2 according to the mass ratio of 1:0.13. After mixing them evenly by mechanical stirring, spray them to prepare a high-reflectivity heat-insulating layer with a dry film thickness of 100 μm.

[0071] (6) Weigh the Ga1 main agent and the Gb1 curing agent according to a mass ratio of 1:0.12. After mixing them evenly by mechanical stirring, a thermally reversible color-changing layer with a dry film thickness of 40 μm is prepared by spraying construction after drying the high-reflection heat-insulating layer, and then the thermally reversible color-changing coating G with a double-layer structure prepared only using conventional thermochromic microcapsules can be obtained.

[0072] Comparative Example 3: Preparation of a coating by compounding conventional thermochromic microcapsules with nano-silica. The preparation process is as follows: (1)Under heating conditions, 3.2 parts of crystal violet lactone, 8 parts of bisphenol F, and 88.8 parts of methyl stearate are completely dissolved to form a clear ternary color-changing system oil phase. The oil phase is added to water containing 0.75% sodium dodecyl sulfate at 65 °C to prepare a thermally reversible color-changing emulsion. Then, 8.4 parts of methylated melamine formaldehyde resin prepolymer are added dropwise to the emulsion under heating conditions and in-situ polymerized at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally reversible color-changing microcapsules c1 can be obtained.

[0073] (2)Weigh 55 parts of fluorocarbon resin, 8.5 parts of acetone, 20 parts of thermally reversible color-changing microcapsules c1, 9 parts of nano-silica particles, 1 part of dispersant, 1 part of leveling agent, 1 part of defoaming agent, and 1.3 parts of bentonite. The fluorocarbon resin, thermally reversible color-changing microcapsules c1, and nano-silica particles are dispersed and mixed for 15 min at a linear velocity of 40 - 60 °C and 6 - 10 m / s using a high-speed disperser, followed by ultrasonic treatment for 4 - 10 min. Then, the remaining components are added to the mixture and dispersed for 30 min to obtain the main agent component Ha1 of the thermally reversible color-changing coating.

[0074] (3)85 parts of isophorone diisocyanate and 15 parts of acetone are dispersed and mixed for 15 min using a high-speed disperser until the system is homogeneous and stable, and then the high-thermal-conductivity thermally reversible color-changing coating curing agent component Hb1 can be obtained.

[0075] (4)The preparation processes of the main agent component Aa2 and the curing agent component Ab2 of the high-reflection heat-insulating coating are as in Example 1.

[0076] (5)Weigh the Aa2 main agent and the Ab2 curing agent according to a mass ratio of 1:0.13. After mixing them evenly by mechanical stirring, a high-reflection heat-insulating layer with a dry film thickness of 100 μm is prepared by spraying construction.

[0077] (6)Weigh the Ha1 main agent and the Hb1 curing agent according to a mass ratio of 1:0.12. After mixing them evenly by mechanical stirring, a thermally reversible color-changing layer with a dry film thickness of 40 μm is prepared by spraying construction after drying the high-reflection heat-insulating layer, and then the thermally reversible color-changing coating H with a double-layer structure prepared only using conventional thermochromic microcapsules can be obtained.

[0078] Comparative Example 4: A coating was prepared using only the hair heat-responsive color-changing microcapsules, and the preparation process was as follows: (1) Under heating conditions, 2.2 parts of 3',6'-dimethoxyfluorane, 3.5 parts of bisphenol S, and 94.3 parts of myristyl alcohol were completely dissolved to form a clear ternary color-changing system oil phase. The oil phase was added to water containing 0.9% sodium dodecylbenzenesulfonate at 65 °C to obtain a thermally reversible color-changing emulsion. Then, 11 parts of a melamine resin prepolymer were dropwise added to the emulsion under heating conditions and in-situ polymerized at 85 °C for 1 h. After filtering and drying the reaction suspension, thermally reversible color-changing microcapsules d1 were obtained.

[0079] (2) 1.5 parts of N,N'-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 part of trithiocarbonate, and 0.035 part of azobisisobutyronitrile were mixed evenly under ultrasonic conditions and completely dissolved at 80 °C. 20 parts of thermally reversible color-changing microcapsules d1 were added thereto and dispersed evenly by high-speed stirring. In-situ RAFT precipitation polymerization was carried out in a nitrogen environment at 80 °C for 24 h, and then filtration and drying were performed to obtain reversible color-changing microcapsules i with a nano-hair structure on the surface.

[0080] (3) 60 parts of a waterborne fluorocarbon resin, 5.6 parts of water, 20 parts of reversible color-changing microcapsules i, 0.6 part of a dispersant, 0.6 part of a leveling agent, and 1 part of a polymer wax were weighed. The waterborne fluorocarbon resin and reversible color-changing microcapsules i were dispersed and mixed using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then, the remaining components were added to the mixture and dispersed for 30 min until the system was uniform and stable to obtain the main component Ia1 of a high thermal conductivity thermally reversible color-changing coating.

[0081] (4) Hydrophilic HDI polyisocyanate was used as the curing agent component Ib1 of the high thermal conductivity thermally reversible color-changing coating.

[0082] (5) The preparation processes of the main component Aa2 and the curing agent component Ab2 of the high-reflection heat-insulating coating were as in Example 1.

[0083] (6) The main component Aa2 and the curing agent component Ab2 were weighed according to a mass ratio of 1:0.13, mechanically stirred and mixed evenly, and a high-reflection heat-insulating layer with a dry film thickness of 100 μm was prepared by spraying construction.

[0084] (7) The main component Ia1 and the curing agent component Ib1 were weighed according to a mass ratio of 1:0.15, mechanically stirred and mixed evenly, and after the high-reflection heat-insulating layer was dried, a thermally reversible color-changing layer with a dry film thickness of 40 μm was prepared by spraying construction to obtain a thermally reversible color-changing coating I with a double-layer structure prepared using only hair heat-responsive color-changing microcapsules.

[0085] Comparative Example 5: A single-layer thermally reversible color-changing temperature control coating, and its preparation process is as follows: (1) The preparation processes of the main component Fa1 and the curing agent component Fb1 of the high thermal conductivity thermally reversible color-changing coating are the same as those in Example 6.

[0086] (2) The preparation processes of the main component Aa2 and the curing agent component Ab2 of the high reflection heat insulation coating are the same as those in Example 1.

[0087] (3) Weigh the main agent Fa1 and the main agent Aa2 according to the mass ratio of 40:100, mix them evenly to obtain the main agent Ja of the thermally reversible color-changing coating. Weigh the curing agent Fb1 and the curing agent Ab2 according to the mass ratio of 3.6:13, and mix them evenly to obtain the curing agent Jb of the thermally reversible color-changing coating.

[0088] (4) Weigh the main agent Ja and the curing agent Jb according to the mass ratio of 140:16.6, use mechanical stirring to mix them evenly, and then a high reflection heat insulation color-changing coating with a dry film thickness of 140 μm can be prepared by spraying construction.

[0089] Comparative Example 6: Preparation of a thermally reversible color-changing temperature control coating with a high nano-silica content, and its preparation process is as follows: (1) Under heating conditions, dissolve 4 parts of 2-phenylamino-3-methyl-6-dibutylamino fluorane, 8 parts of bisphenol A and 88 parts of methyl stearate completely to form a clear ternary color-changing system oil phase. Add the oil phase to water containing 0.7% sodium salt of styrene maleic anhydride copolymer at 65 °C to prepare a thermally reversible color-changing emulsion. Then, drop 10 parts of methyl melamine formaldehyde resin prepolymer into the emulsion under heating conditions, and carry out in-situ polymerization at 85 °C for 1 h. After filtering and drying the reaction suspension, the thermally reversible color-changing microcapsules e1 can be obtained.

[0090] (2) Mix 1.5 parts of N,N'-methylenebisacrylamide, 4.5 parts of ethanol, 295 parts of toluene, 0.25 parts of trithiocarbonate and 0.035 parts of azobisisobutyronitrile evenly under ultrasonic conditions and dissolve them completely at 80 °C. Add 15 parts of thermally reversible color-changing microcapsules e1 and 15 parts of nano-silica particles into it, and disperse them evenly by high-speed stirring. Carry out in-situ RAFT precipitation polymerization in a nitrogen environment at 80 °C for 24 h, and then filter and dry to obtain a mixed filler K of reversible color-changing microcapsules with a nano-hair structure on the surface and nano-silica.

[0091] (3)Weigh 58 parts of silicone resin, 9 parts of butyl acetate, 27 parts of mixed filler K, 0.6 part of leveling agent and 0.6 part of defoaming agent. Disperse and mix the silicone resin and mixed filler e using a high-speed disperser at a linear velocity of 40 - 60 °C and 6 - 10 m / s for 15 min, followed by ultrasonic treatment for 4 - 10 min. Then add the remaining components to the mixture and disperse for 30 min until the system is homogeneous and stable to obtain the main component Ka1 of the high thermal conductivity thermally reversible color-changing coating.

[0092] (4)Disperse and mix 60 parts of dicyclohexylmethane diisocyanate, 35 parts of hexamethylene diisocyanate biuret and 5 parts of butyl acetate using a high-speed disperser for 15 min until the system is homogeneous and stable to obtain the curing agent component Kb1 of the high thermal conductivity thermally reversible color-changing coating.

[0093] (5)The preparation process of the main component Aa2 and curing agent component Ab2 of the high reflectivity heat insulation coating is as in Example 1.

[0094] (6)Weigh the main agent Aa2 and curing agent Ab2 according to a mass ratio of 1:0.13, mix them evenly using mechanical stirring, and prepare a high reflectivity heat insulation layer with a dry film thickness of 100 μm by spraying construction.

[0095] (7)Weigh the main agent Ka1 and curing agent Kb1 according to a mass ratio of 1:0.09, mix them evenly using mechanical stirring, and after the high reflectivity heat insulation layer is dried, prepare a thermally reversible color-changing layer with a dry film thickness of 40 μm by spraying construction to obtain the double-layer structure coating K.

[0096] Perform performance test comparisons on the thermally reversible color-changing temperature control coatings based on hair structure microcapsules prepared in Examples 1 - 6 of the present invention and the comparative coatings of Comparative Examples 1 - 6. Test the apparent lightness value of the coating at different temperatures, the solar reflectance at different temperatures, the lateral thermal conductivity of the coating surface, the color change color distribution and the cycle stability, and organize the relevant test results in Table 1: Table 1 Performance test results of the color-changing temperature control coating It can be seen from the data in Table 1 that the thermally reversible color-changing temperature control coatings based on hair structure microcapsules prepared in the examples have significant differences in lightness value and solar reflectance under low-temperature and high-temperature conditions, the change in temperature control ability is more obvious, the lateral heat conduction is faster, the overall color change is more uniform, and it has a better effect under large-scale use conditions and a better visual appearance. This is due to the synergistic effect of the hair structure microcapsules and the uniformly distributed nano-silica contained therein, and there is no significant degradation of the color-changing performance after 300 color change cycles of the system, and the long-term service performance is better. The test results confirm that the examples of the present invention have strong practical value.

[0097] Comparative Example 1 is a commercially available thermochromic coating. It can be seen from the results that the color-changing ability of the commercially available color-changing coating is relatively weak, and due to the absence of high-reflection heat-insulating filler components, its reflection performance is very poor. Even under conditions with a relatively high lightness value, the reflection is still relatively low. Therefore, it does not have the ability to control temperature by reflection, and the stability of the thermochromic components in it is relatively poor. After 300 color-changing cycles, its color-changing performance has decreased significantly.

[0098] Comparative Example 2 is a double-layer thermochromic coating prepared only using conventional color-changing microcapsules. It can be seen that due to the relatively poor dispersion performance of the conventional microcapsules, and the color-changing ability and temperature control effect are both worse than those of the examples. And because it does not contain enhanced thermal conductivity fillers, the thermal conductivity coefficient of its surface layer is relatively low. Therefore, this also results in relatively poor color uniformity during the color-changing process. Although nano-silica is added as an enhanced thermal conductivity filler in Comparative Example 3, due to the lack of the overlapping effect of the hair structure, the uniformity of its distribution and the thermal bridge effect are relatively weak, making its enhancement of the thermal conductivity performance limited and the effect relatively weak.

[0099] Comparative Example 4 is a double-layer thermochromic coating prepared only using hair-structure color-changing microcapsules. It can be seen that its dispersion performance is relatively good, but also because it does not contain enhanced thermal conductivity fillers and has poor thermal conductivity, resulting in relatively weak color-changing uniformity. Comparative Example 5 is a thermochromic coating prepared by mixing a high-reflection heat-insulating layer and a high-thermal-conductivity thermochromic layer into a single-layer structure. It can be seen from the results that due to the relatively low concentration of microcapsules and the relatively strong coloring power of rutile titanium dioxide, its color-changing performance is greatly affected, and it is difficult to achieve the intelligent temperature control effect, and the effect of enhancing the thermal conductivity coefficient is also significantly diluted. This shows the importance of layered preparation. Example 6 is a double-layer thermochromic coating prepared using a relatively large amount of nano-silica particles. It can be seen that due to the increase in nano-silica and the decrease in color-changing microcapsules, its color-changing ability has decreased significantly, and due to relatively few hair channels, the thermal conductivity enhancement effect is also affected.

[0100] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A thermoreversible color-changing temperature-control coating based on hair-structured microcapsules, characterized in that It is a double-layer temperature control coating consisting of a highly reflective heat-insulating layer and a highly thermally conductive thermochromic layer; The high-reflective heat-insulating layer is prepared from a high-performance reflective heat-insulating coating prepared with rutile titanium dioxide and hollow glass microspheres as fillers; the high-thermal-conductivity thermochromic layer is prepared from a high-thermal-conductivity thermochromic coating prepared with thermoreversible color-changing microcapsules with hair structures on the surface and nano-silicon dioxide as fillers; the dry film thicknesses of the high-reflective heat-insulating layer and the high-thermal-conductivity thermochromic layer are 80-120 μm and 30-50 μm, respectively.

2. According to claim 1, a thermoreversible color-changing temperature-control coating based on hair-structured microcapsules, characterized in that The high thermal conductivity thermo-induced reversible color-changing coating is composed of an A1 component main agent and a B1 component curing agent, wherein the A1 component main agent is prepared from a matrix resin, a hair structure microcapsule and a nano-silicon dioxide composite filler, a solvent, a functional additive and a rheology regulator, wherein the mass ratio of the hair structure microcapsule to the nano-silicon dioxide in the composite filler is 1: (0.3-0.6), the B1 component curing agent is prepared from a curing agent and a solvent, and the mass ratio of the A1 component main agent to the B1 component curing agent is 1: (0.08-0 .22); wherein the high-performance reflective heat-insulating coating is composed of a main agent of component A2 and a curing agent of component B2, wherein the main agent of component A2 is prepared from a base resin, rutile titanium dioxide, hollow glass microspheres, a solvent, a functional additive and a rheology regulator, wherein the mass ratio of rutile titanium dioxide to hollow glass microspheres is 1:(0.8~1.2), the curing agent of component B2 is prepared from a curing agent and a solvent, and the mass ratio of the main agent of component A2 to the curing agent of component B2 is 1:(0.08~0.22).

3. According to claim 1, a thermoreversible color-changing temperature-control coating based on hair-structured microcapsules, characterized in that The method for preparing the filler in the high thermal conductivity thermo-induced reversible color-changing coating comprises the following steps: (1) A ternary thermochromic core material consisting of a pigment, a color developer and a solvent is dissolved and added to water containing an emulsifier and then emulsified at high speed under heating conditions at 65°C to obtain a thermochromic emulsion; (2) A resin prepolymer is added dropwise to the reversible color emulsion at a constant speed under heating and stirring conditions, and after the addition is completed, it is in-situ polymerized at 85°C for 1 hour, and the suspension after the reaction is filtered and dried to obtain thermochromic microcapsules; (3) N,N-methylenebisacrylamide, ethanol, toluene, RAFT agent and initiator are mixed and dissolved completely, and reversible color microcapsules and nano-silica are added thereto and dispersed evenly by high-speed stirring, and in-situ RAFT precipitation polymerization is carried out in a nitrogen environment at 80°C for 24 hours, and then filtered and dried to obtain a reversible color microcapsule and nano-silica mixed filler with a nano-hair structure on the surface.

4. A preparation method according to claim 3, characterized in that The pigment is at least one of crystal violet lactone, 2-phenylamino-3-methyl-6-dibutylaminofluoran, and 3',6'-dimethoxyfluoran; the developer is at least one of bisphenol A, bisphenol F, and bisphenol S; the solvent contains at least one of tetradecanol, tricaprin, methyl octadecanoate, and ethyl octadecanoate; the mass concentration of the pigment molecule is 0.8-6%, and the mass ratio of the pigment to the developer is 1:(1.5-4) based on the mass of the ternary color-changing core material; the emulsifier is at least one of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, and styrene maleic anhydride copolymer sodium salt, and its mass concentration is 0.5-1%; the resin prepolymer is at least one of melamine resin prepolymer, urea-formaldehyde resin prepolymer, methyl melamine formaldehyde resin prepolymer, polyurethane resin prepolymer, and acrylic resin, and the amount used is 5-13% of the total amount.

5. A preparation method according to claim 3, characterized in that The mass concentration of the N,N-methylenebisacrylamide is 0.5-1.5%, the mass concentration of ethanol is 1.5-3%, the RAFT agent is at least one of dithiobenzoate, trithiocarbonate, and dithiocarbamate, and its usage is 8-12% of the monomer amount; the initiator is at least one of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and lauroyl peroxide, and its usage is 1-2% of the monomer amount.

6. The thermoreversible color-changing temperature-control coating based on hair-structured microcapsules according to claim 1, characterized in that In the main agent components of the two coatings, the contents of base resin, filler, solvent, functional additive and rheology modifier are 50-72%, 22-33%, 3-10%, 0.5-3.5% and 0.5-2.0% respectively, calculated on the total mass of the main agent; wherein the base resin is at least one of silicone resin, fluorocarbon resin, polyurethane resin and acrylic modified polyurethane resin; wherein the solvent is at least one of xylene, acetone, n-butanol, butyl acetate, dimethylformamide, propylene glycol methyl ether acetate and water; wherein the functional additive is at least one of dispersant, defoamer, leveling agent and adhesion promoter; wherein the rheology modifier is at least one of bentonite, hydrated magnesium silicate, fumed silica and polymer wax.

7. The thermoreversible color-changing temperature-control coating based on hair-structured microcapsules according to claim 1, characterized in that In the curing agent of component B of the two coatings, the contents of isocyanate and solvent are 85%-100% and 0-15%, respectively, based on the total mass of component B; wherein the isocyanate is at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane dimethylene diisocyanate, xylylene diisocyanate, hydrophilic HDI polyisocyanate, polymethylene polyphenyl polyisocyanate, hexamethylene diisocyanate trimer and hexamethylene diisocyanate biuret; and the solvent is at least one of xylene, butanone, ethanol, n-butanol, butyl acetate, dimethylformamide, propylene glycol methyl ether acetate and water.

8. The thermoreversible color-changing temperature-control coating based on hair-structured microcapsules according to claim 1, characterized in that The preparation methods of the two coatings include the following steps: (1) Weigh appropriate amounts of each component, use a high-speed disperser to disperse and mix the base resin and filler for 15 minutes at 40-60°C and a line speed of 6-10 m / s, then perform ultrasonic treatment for 4-10 minutes, and then add the remaining components to the mixture and disperse for 30 minutes until the system is uniform and stable to obtain the coating main agent component; (2) Use a high-speed disperser to disperse and mix the isocyanate and solvent for 15 minutes until the system is uniform and stable to obtain the curing agent component.

9. The thermoreversible color-changing temperature-control coating based on hair-structured microcapsules according to claim 1, characterized in that The on-site construction method of the two coatings described herein can be any one of spraying, dipping, roller coating and brushing.

10. Application of a thermoreversible color-changing temperature-control coating based on hair-structured microcapsules as claimed in claim 1 as a surface temperature-control material for structures such as houses, buildings, factories, cold storages, industrial storage tanks, transportation infrastructure, and small components.

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