A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures

Abstract

The present invention discloses a high-efficiency temperature-control and anti-cracking protective coating for concrete structures. This high-efficiency temperature-control and anti-cracking protective coating is prepared by mixing a resin containing a Janus special filler and a curing agent strong material. The present invention introduces Janus particles with large and small composite surface amphiphilic partitions as particulate fillers. During the coating drying and curing process, the composite Janus filler particles undergo a particle enrichment self-assembly process under relevant effects to form a regular microstructure with a cluster shape, and the microstructures also produce particle interactions, so that the surface of the cured coating presents a regular micro-nanostructure distribution. Compared with the irregular uniform distribution of traditional isotropic particle fillers, the regular microstructure formed by the composite Janus particle filler during the drying and curing process significantly improves the reflection, scattering and heat radiation capabilities of the coating surface to sunlight, and significantly enhances the thermal insulation and temperature control capabilities. Compared with conventional surface microstructure treatment processes, the present invention utilizes compounded Janus particle fillers to self-assemble and spontaneously form a regular microstructure. The process is relatively simple, not limited to specific professional equipment, and can be produced and applied on a large scale. It is of great significance for temperature control, protection, energy conservation and environmental protection of concrete structures in exposed environments under various conditions.

Description

Technical Field

[0001] The present invention belongs to the field of fine polymer materials, and specifically relates to the preparation, construction and application in the field of surface temperature control of a high-efficiency temperature-control and anti-cracking protective coating for concrete structures based on self-assembly of Janus particle fillers. Background Art

[0002] Thermal insulation and temperature-control materials typically possess unique photothermal properties. When attached to the surface of a structure requiring temperature control using appropriate technologies or equipment, these materials leverage their inherent photothermal properties to improve the structure's temperature response to ambient temperature, thermal radiation, and other heat sources, thereby controlling the structure's internal temperature. Thermal insulation and temperature-control materials have garnered significant attention in my country in recent years, finding widespread application in fields such as construction, textiles, electrical appliances, military, and aerospace. High-emissivity thermal insulation and temperature-control materials are a newly emerging type of high-efficiency surface temperature-control material. Their key feature is that they achieve energy-saving and environmentally friendly temperature control by reducing surface absorption of sunlight and significantly enhancing its outward radiation, particularly within the 8-13μm atmospheric radiation window. Compared to thermal insulation or reflective temperature-control materials, high-emissivity thermal insulation and temperature-control materials can even achieve radiative cooling under daylight conditions, making them a key development direction for future temperature-control materials.

[0003] However, the current mainstream preparation method of high-radiation thermal insulation and temperature control materials mainly achieves the effect of radiation temperature control by performing micro-nano processing on the material surface to form an ordered micro-nano structure. The complex preparation process, high cost, and unknown durability all restrict the use of radiation temperature control materials. How to use special disordered structures to simply obtain the specific optical properties that only conventional ordered structures have, and how to prepare radiation temperature control materials on a large scale, at low cost, and with high efficiency are major problems they face.

[0004] At present, relevant researchers have conducted research and development on the preparation of high-radiation refrigeration temperature control materials. Patent CN112175458A discloses an adaptive temperature-controlling radiant refrigeration coating and its application. By introducing reversible thermochromic materials or phase change materials into the radiant refrigeration coating, the radiant refrigeration has switching characteristics under different temperature conditions, thereby achieving the effect of intelligent temperature control. Patent CN113262971A discloses an intelligent temperature control material and its preparation method and application. By introducing highly reflective pigments to achieve radiant refrigeration, and by introducing a thermochromic layer to achieve reversible conversion between insulation and refrigeration. Patent CN115386273A discloses a daytime radiant refrigeration coating. By using polymethylpentene with high transmittance coupled with silica microspheres to achieve high infrared absorption, a radiant refrigeration coating that can reduce temperature under high solar radiation during the day is prepared.

[0005] Although the above studies have made certain progress in the preparation of radiative cooling materials, their preparation methods are relatively complex, their surface properties are relatively insufficient, and their durability and radiative cooling performance need to be further improved.

[0006] Janus particles are particles with non-centrosymmetric structures or properties. Typically, their surfaces simultaneously possess two distinct chemical compositions, each strictly partitioned. Because they have two distinct parts with distinct properties, they exhibit significant potential in many applications not possessed by isotropic particles, such as self-assembly, molecular recognition, and the construction of complex structures. Over the past 30 years, Janus materials have experienced rapid development, demonstrating numerous novel properties and promising applications. Furthermore, because Janus particles possess a variety of reactive chemical groups with distinct partitions, they can be functionalized with specialized materials. For example, patent CN104945569A provides amphiphilic Janus particles for superhydrophobic coatings. One side of the particles has a hydrophobic side with multiple polymer protrusions, while the other side has a smooth hydrophilic side. This allows for easy self-orientation on surfaces or interfaces, with the hydrophobic side exhibiting hydrophobicity. However, research on how to use Janus particles to form regular micro- and nanostructures for surface applications in radiative cooling is currently lacking.

[0007] Because Janus particles can form regular micro-nanostructures driven by their own self-assembly, their application in coating materials to improve the surface micro-nano regularity of related materials and further enhance the related radiative cooling capabilities has great application prospects. Therefore, research on high-efficiency temperature-control coatings based on Janus particle fillers can effectively improve the actual effectiveness of radiative cooling coatings, reduce the complexity of their preparation and construction, and obtain materials with better performance and durability, which is of great significance to industry advancement. Summary of the Invention

[0008] The purpose of the present invention is to solve the above problems, provide a high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, and provide methods for its preparation, construction and application.

[0009] The high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures disclosed herein is a surface functional coating obtained by mixing a resin component A and a curing agent component B and applying the mixture. The resin component A is prepared from a base resin, a special filler, a solvent, a functional additive, a color paste, and a rheology modifier. The special filler is an amphiphilic Janus particle filler. The curing agent component B is prepared from a curing agent and a solvent. The mass ratio of the resin component A to the curing agent component B is 1:(0.08-0.22).

[0010] The amphiphilic Janus particle filler in this high-efficiency temperature-control and crack-resistant protective coating is an amphiphilic particle with a hydrophilic group on one side of the surface and a hydrophobic group on the other side; its particle size distribution is that small particles in the range of 0.5-2μm account for 15-25% by mass, and large particles in the range of 40-80μm account for 75-85% by mass.

[0011] The preparation process of the amphiphilic Janus particle filler in the high-efficiency temperature-controlling anti-cracking protective coating is as follows: (1) fully oxidizing the surface of particles of suitable size and then modifying them with an aminosilane coupling agent; (2) dispersing the modified particles at high speed in a paraffin / water emulsion under high temperature conditions and fixing them by cooling; (3) grafting hydrophobic groups onto the surface of the fixed particles; and (4) eluting the paraffin and grafting hydrophilic groups onto the remaining part of the particle surface; wherein the particles are at least one of silica particles, ferroferric oxide particles, silicon nitride particles, silicon carbide particles, polystyrene particles and polyvinyl pyrrolidone particles; the hydrophilic group is at least one of carboxyl, amino and sulfonic acid groups; and the hydrophobic group is at least one of methyl, ethyl, propyl, phenyl and 4-12 carbon long-chain alkane groups.

[0012] In the resin of component A of the high-efficiency temperature-controlling and crack-resistant protective coating, the contents of base resin, special filler, solvent, functional additive, color paste and rheology regulator are 50-72%, 22-33%, 3-10%, 0.5-3.5%, 0.1-2.5% and 0.5-2.0% respectively, calculated on the total mass of component A; the base resin is at least one of solvent-based or water-based silicone resin, acrylate-modified silicone resin, fluororesin, fluorocarbon resin, polyurethane resin and acrylic acid-modified polyurethane resin; the solvent is petroleum ether, benzene, toluene , xylene, n-hexane, chloroform, acetone, butanone, ethanol, propanol, n-butanol, ethyl acetate, butyl acetate, dimethylformamide, dimethyl sulfoxide and water; the functional additive is at least one of a dispersant, a defoamer, a leveling agent, a UV absorber, an antioxidant and a mildewproof agent; the color paste is at least one of the water-based or solvent-based black, brown and gray color pastes of Clariant, Degussa, CPS, BASF and Shiming; the rheology regulator is at least one of bentonite, hydrated magnesium silicate, fumed silica, polyamide wax and polyethylene wax.

[0013] In the B component curing agent of the high-efficiency temperature-controlling and crack-resistant protective coating, the contents of the curing agent and the solvent are 70%-95% and 5-30% respectively, based on the total mass of the B component; the curing agent is at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane dimethylene diisocyanate, toluene diisocyanate trimer, hexamethylene diisocyanate trimer, hydrophilic HDI polyisocyanate and hydrophilic modified IPDI polyisocyanate; and the solvent is at least one of petroleum ether, benzene, toluene, xylene, n-hexane, chloroform, acetone, butanone, ethanol, propanol, n-butanol, ethyl acetate, butyl acetate, dimethylformamide, dimethyl sulfoxide and water.

[0014] The preparation method of the component A resin and the component B curing agent of the high-efficiency temperature-controlling and crack-resistant protective coating comprises the following steps:

[0015] (1) Weigh appropriate amounts of each component, dispersing and mixing the base resin and special filler using a high-speed disperser at 40-60°C at a speed of 6-10 m / s, followed by ultrasonic treatment for 4-10 min to obtain mixture A1;

[0016] (2) The solvent, functional additive, color paste and rheology modifier were mixed at room temperature, pre-dispersed at low speed for 5 minutes using a high-speed disperser, allowed to stand for 10 minutes, and then dispersed at high speed for 10 minutes at a linear speed of 18-24 m / s to obtain mixture A2;

[0017] (3) Add the A2 mixture to the A1 mixture at a linear speed of 6-10 m / s and disperse for 5-10 min until the system is uniform and stable to obtain the A component resin;

[0018] (4) The curing agent and solvent are dispersed and mixed using a high-speed disperser for 10-15 minutes until the system is uniform and stable to obtain the curing agent component B.

[0019] The dry film thickness of the high-efficiency temperature-controlling anti-cracking protective coating after construction is 40-100 μm, and the coating can be constructed by any one of spraying, dipping, roller coating and brushing.

[0020] The positive effects of the high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures of the present invention are:

[0021] Compared to existing radiant temperature-control coating materials, the present invention introduces a composite of large and small amphiphilic special Janus particles as fillers to replace traditional isotropic particle fillers. During the drying and curing process, the coating containing the composite amphiphilic Janus filler particles will first undergo enrichment and self-assembly of small particles around large particles to form tiny clusters. The inside and outside of the cluster microstructure have different chemical properties. Further self-assembly under the interaction of hydrophilic and hydrophobic factors will form a surface with a regular distribution of clustered microstructures. Therefore, compared to the irregular and uniform distribution of traditional isotropic particles, the Janus filler particles will form a regularly distributed microstructure during the drying and curing process. This microstructure will appear on the coating surface and significantly improve the coating surface's ability to reflect, scatter, and radiate heat from sunlight, forming a high-performance radiant cooling and temperature-control coating.

[0022] Compared with the prior art, the high-efficiency radiative cooling and temperature-control coating of the present invention has better radiative cooling and temperature-control performance due to its better surface regular microstructure. Compared with the general surface microstructure treatment process, the present invention utilizes Janus particle fillers to self-assemble and spontaneously form a regular microstructure. The process is relatively simple and is not limited to specific professional equipment, and can be produced and applied on a large scale. In addition, the microstructure of the coating is formed by particles with a certain strength, and the outside is coated with a relevant weather-resistant resin. Therefore, the wear resistance, weather resistance, and corrosion resistance of the coating are significantly improved compared to conventional microstructure coatings, and it can be used for structural temperature control protection in a variety of complex environments.

[0023] From the above description, it can be seen that the high-efficiency temperature-control and anti-cracking protective coating for concrete structures provided by the present invention has a clear mechanism of action, a simple production process, and excellent performance, is suitable for large-scale production, and is of great significance for temperature control, protection, energy conservation and environmental protection of outdoor structures under various conditions. DETAILED DESCRIPTION

[0024] The present invention will be described in further detail below with reference to specific embodiments.

[0025] Example 1: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A1 and the curing agent component B1 is as follows:

[0026] (1) Weigh 66 parts of silicone resin and 25 parts of Janus silica particles with carboxyl and phenyl groups, disperse and mix them in a high-speed disperser at 45°C and a linear speed of 8 m / s for 15 minutes, and then perform ultrasonic treatment for 5 minutes to obtain a mixture Aa-1;

[0027] (2) Weigh 6.3 parts of xylene, 1 part of dispersant, 0.5 part of defoamer, 0.6 part of Klein RLSN01 and 0.6 part of fumed silica and mix them at room temperature. Use a high-speed disperser to pre-disperse them at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 20 m / s to disperse them at high speed for 10 minutes to obtain the Ab-1 mixture.

[0028] (3) Add the Ab-1 mixture to the Aa-1 mixture at a linear speed of 7 m / s and disperse for 8 min until the system is uniform and stable to obtain the A1 component resin;

[0029] (4) Weigh 85 parts of toluene diisocyanate and 15 parts of xylene, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B1 component curing agent.

[0030] Resin A1 and curing agent B1 were weighed in a mass ratio of 1:0.13, mixed evenly using mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 60 μm.

[0031] Example 2: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A2 and the curing agent component B2 is as follows:

[0032] (1) Weigh 56 parts of PVDF resin and 29 parts of Janus ferrosoferric oxide particle filler with carboxyl and hexyl groups, use a high-speed disperser to disperse and mix at 40°C and a linear speed of 10 m / s for 15 minutes, and then perform ultrasonic treatment for 6 minutes to obtain a mixture Aa-2;

[0033] (2) Weigh 10 parts of water, 1 part of leveling agent, 0.5 parts of defoaming agent, 0.3 parts of mildew inhibitor, 1.8 parts of Degussa C8 and 1.4 parts of water and magnesium silicate and mix them at room temperature. Use a high-speed disperser to pre-disperse them at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 20 m / s to disperse them at high speed for 10 minutes to obtain Ab-2 mixture.

[0034] (3) Add the Ab-2 mixture to the Aa-2 mixture at a linear speed of 8 m / s and disperse for 10 min until the system is uniform and stable to obtain the A2 component resin;

[0035] (4) The curing agent of component B2 is hydrophilic HDI polyisocyanate.

[0036] A2 resin and B2 curing agent were weighed in a mass ratio of 1:0.15, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 80 μm.

[0037] Example 3: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A3 and the curing agent component B3 is as follows:

[0038] (1) Weigh 71 parts of polyurethane resin and 22 parts of Janus silica particle filler with amino group and dodecyl group, disperse and mix them in a high-speed disperser at 55°C and a linear speed of 10 m / s for 15 min, and then ultrasonically treat for 8 min to obtain a mixture Aa-3;

[0039] (2) 4.65 parts of butanone, 0.8 parts of dispersant, 0.5 parts of antioxidant, 1.3 parts of BASF L0080 and 0.7 parts of fumed silica were weighed and mixed at room temperature. The mixture was pre-dispersed at low speed for 5 minutes using a high-speed disperser. After standing for 10 minutes, the mixture was dispersed at a high speed of 22 m / s for 10 minutes to obtain the Ab-3 mixture.

[0040] (3) Add the Ab-3 mixture to the Aa-3 mixture at a linear speed of 8 m / s and disperse for 10 min until the system is uniform and stable to obtain the A3 component resin;

[0041] (4) Weigh 95 parts of isophorone diisocyanate and 5 parts of butanone, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B3 component curing agent.

[0042] A3 resin and B3 curing agent were weighed in a mass ratio of 1:0.18, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 100 μm.

[0043] Example 4: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A4 and the curing agent component B4 is as follows:

[0044] (1) Weigh 53 parts of acrylic modified polyurethane resin and 32 parts of Janus silicon nitride particle filler with carboxyl and phenyl groups, disperse and mix them in a high-speed disperser at 40°C and a linear speed of 6 m / s for 15 minutes, and then ultrasonically treat for 5 minutes to obtain an Aa-4 mixture;

[0045] (2) 9.1 parts of water, 1 part of dispersant, 0.6 parts of leveling agent, 0.3 parts of mildew inhibitor, 2 parts of Shiming SM8809 and 2 parts of bentonite were weighed and mixed at room temperature. The mixture was pre-dispersed at low speed for 5 minutes using a high-speed disperser. After standing for 10 minutes, the mixture was dispersed at a linear speed of 24 m / s for 10 minutes to obtain the Ab-4 mixture.

[0046] (3) Add the Ab-4 mixture to the Aa-4 mixture at a linear speed of 8 m / s and disperse for 8 min until the system is uniform and stable to obtain the A4 component resin;

[0047] (4) The curing agent of component B4 is hydrophilic HDI polyisocyanate.

[0048] A4 resin and B4 curing agent were weighed in a mass ratio of 1:0.20, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 50 μm.

[0049] Example 5: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A5 and the curing agent component B5 is as follows:

[0050] (1) Weigh 62 parts of fluorocarbon resin and 30 parts of Janus silica particle filler with amino and octyl groups, disperse and mix them in a high-speed disperser at 40°C and a linear speed of 9 m / s for 15 minutes, and then ultrasonically treat for 5 minutes to obtain a mixture Aa-5;

[0051] (2) Weigh 5.45 parts of butyl acetate, 1 part of leveling agent, 0.4 part of defoamer, 0.55 parts of BASF L0080 and 0.6 parts of polyethylene wax and mix them at room temperature. Use a high-speed disperser to pre-disperse them at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 22 m / s to disperse them at high speed for 10 minutes to obtain the Ab-5 mixture.

[0052] (3) Add the Ab-5 mixture to the Aa-5 mixture at a linear speed of 8 m / s and disperse for 9 min until the system is uniform and stable to obtain the A5 component resin;

[0053] (4) Weigh 90 parts of dicyclohexylmethane diisocyanate and 10 parts of butyl acetate, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B5 component curing agent.

[0054] A5 resin and B5 curing agent were weighed in a mass ratio of 1:0.09, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 40 μm.

[0055] Example 6: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the A6 component resin and the B6 component curing agent is as follows:

[0056] (1) Weigh 60 parts of acrylate-modified silicone resin and 28 parts of Janus polystyrene particle filler with sulfonic acid groups and phenyl groups, disperse and mix them in a high-speed disperser at 40°C and a linear speed of 10 m / s for 15 minutes, and then perform ultrasonic treatment for 5 minutes to obtain an Aa-6 mixture;

[0057] (2) Weigh 9.4 parts of dimethylformamide, 0.4 parts of defoaming agent, 0.4 parts of UV absorber, 0.9 parts of Clariant RLSN01 and 0.9 parts of fumed silica, mix them at room temperature, use a high-speed disperser to pre-disperse them at low speed for 5 minutes, let them stand for 10 minutes, and then use a linear speed of 20 m / s to disperse them at high speed for 10 minutes to obtain the Ab-6 mixture;

[0058] (3) Add the Ab-6 mixture to the Aa-6 mixture at a linear velocity of 6 m / s and disperse for 8 min until the system is homogeneous and stable to obtain the A6 component resin;

[0059] (4) Weigh 95 parts of cyclohexane dimethylene diisocyanate and 5 parts of dimethylformamide, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B6 component curing agent.

[0060] A6 resin and B6 curing agent were weighed in a mass ratio of 1:0.15, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 80 μm.

[0061] Example 7: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A7 and the curing agent component B7 is as follows:

[0062] (1) Weigh 68 parts of fluorocarbon resin and 23 parts of Janus silicon carbide particle filler with sulfonic acid group and dodecyl group, disperse and mix them in a high-speed disperser at 45°C and a linear speed of 10 m / s for 15 minutes, and then perform ultrasonic treatment for 5 minutes to obtain Aa-7 mixture;

[0063] (2) Weigh 4 parts of water, 0.7 parts of leveling agent, 0.9 parts of dispersant, 0.6 parts of HBIS CH2 and 1.2 parts of polyamide wax and mix them at room temperature. Use a high-speed disperser to pre-disperse them at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 20 m / s to disperse them at high speed for 10 minutes to obtain the Ab-7 mixture.

[0064] (3) Add the Ab-7 mixture to the Aa-7 mixture at a linear speed of 8 m / s and disperse for 8 min until the system is uniform and stable to obtain the A7 component resin;

[0065] (4) The curing agent of component B4 is hydrophilic modified IPDI polyisocyanate.

[0066] A7 resin and B7 curing agent were weighed in a mass ratio of 1:0.1, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 60 μm.

[0067] Example 8: A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, wherein the preparation process of the resin component A8 and the curing agent component B8 is as follows:

[0068] (1) Weigh 62 parts of silicone resin and 27 parts of Janus polyvinyl pyrrolidone particle filler with carboxyl and hexyl groups, disperse and mix them in a high-speed disperser at 50°C and a linear speed of 8 m / s for 15 minutes, and then perform ultrasonic treatment for 5 minutes to obtain an Aa-8 mixture;

[0069] (2) Weigh 6.9 parts of xylene, 1 part of dispersant, 0.5 part of defoamer, 1 part of leveling agent, 0.6 part of BASF L0080 and 1 part of fumed silica, mix them at room temperature, use a high-speed disperser to pre-disperse them at low speed for 5 minutes, let them stand for 10 minutes, and then use a linear speed of 18 m / s to disperse them at high speed for 10 minutes to obtain the Ab-8 mixture;

[0070] (3) Add the Ab-8 mixture to the Aa-8 mixture at a linear speed of 8 m / s and disperse for 8 min until the system is uniform and stable to obtain the A8 component resin;

[0071] (4) Weigh 60 parts of isophorone diisocyanate, 33 parts of hexamethylene diisocyanate trimer and 7 parts of chloroform, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B8 component curing agent.

[0072] A8 resin and B8 curing agent were weighed in a mass ratio of 1:0.13, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 70 μm.

[0073] Comparative Example 1: Commercially available radiation temperature control coating material

[0074] Take a certain brand of radiation temperature control coating material on the market, mix the two components according to the recommended ratio, and then spray it to obtain a radiation temperature control coating with a dry film thickness of 80μm.

[0075] Comparative Example 2: Conventional filler temperature-controlled anti-cracking protective coating, the preparation process of its A9 component resin and B9 component curing agent is as follows:

[0076] (1) Weigh 66 parts of silicone resin and 25 parts of titanium dioxide, where the size distribution of titanium dioxide is the same as that of Janus filler, and use a high-speed disperser to disperse and mix at 45°C and a linear speed of 8 m / s for 15 minutes, followed by ultrasonic treatment for 5 minutes to obtain an Aa-9 mixture;

[0077] (2) Weigh 6.3 parts of xylene, 1 part of dispersant, 0.5 part of defoamer, 0.6 part of Klein RLSN01 and 0.6 part of fumed silica and mix them at room temperature. Use a high-speed disperser to pre-disperse them at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 20 m / s to disperse them at high speed for 10 minutes to obtain an Ab-9 mixture.

[0078] (3) Add the Ab-9 mixture to the Aa-9 mixture at a linear velocity of 7 m / s and disperse for 8 min until the system is homogeneous and stable to obtain the A9 component resin;

[0079] (4) Weigh 85 parts of toluene diisocyanate and 15 parts of xylene, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B9 component curing agent.

[0080] A9 resin and B9 curing agent were weighed in a mass ratio of 1:0.13, mixed evenly by mechanical stirring, and then sprayed to obtain a temperature-controlled anti-cracking protective coating with a dry film thickness of 60 μm.

[0081] Comparative Example 3: The preparation process of the hydrophilic particle filler temperature-control anti-cracking protective coating, the A10 component resin and the B10 component curing agent is as follows:

[0082] (1) Weigh 56 parts of PVDF resin and 29 parts of ferrosoferric oxide particle filler with only carboxyl groups, disperse and mix them in a high-speed disperser at 40°C and a linear speed of 10 m / s for 15 minutes, and then perform ultrasonic treatment for 6 minutes to obtain an Aa-10 mixture;

[0083] (2) Weigh 10 parts of water, 1 part of leveling agent, 0.5 parts of defoaming agent, 0.3 parts of mildew inhibitor, 1.8 parts of Degussa C8 and 1.4 parts of water and magnesium silicate and mix them at room temperature. Use a high-speed disperser to pre-disperse at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 20 m / s to disperse at high speed for 10 minutes to obtain Ab-10 mixture.

[0084] (3) Add the Ab-10 mixture to the Aa-10 mixture at a linear speed of 8 m / s and disperse for 10 min until the system is uniform and stable to obtain the A10 component resin;

[0085] (4) The curing agent of component B10 is hydrophilic HDI polyisocyanate.

[0086] A10 resin and B10 curing agent were weighed in a mass ratio of 1:0.15, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 80 μm.

[0087] Comparative Example 4: The preparation process of the hydrophilic particle filler temperature-control anti-cracking protective coating, the A11 component resin and the B11 component curing agent is as follows:

[0088] (1) Weigh 56 parts of PVDF resin and 29 parts of ferrosoferric oxide particle filler with only hexyl groups, disperse and mix them in a high-speed disperser at 40°C and a linear speed of 10 m / s for 15 minutes, and then perform ultrasonic treatment for 6 minutes to obtain an Aa-11 mixture;

[0089] (2) Weigh 10 parts of water, 1 part of leveling agent, 0.5 parts of defoaming agent, 0.3 parts of mildew inhibitor, 1.8 parts of Degussa C8 and 1.4 parts of water and magnesium silicate and mix them at room temperature. Use a high-speed disperser to pre-disperse at low speed for 5 minutes. After standing for 10 minutes, use a linear speed of 20 m / s to disperse at high speed for 10 minutes to obtain Ab-11 mixture.

[0090] (3) Add the Ab-11 mixture to the Aa-11 mixture at a linear speed of 8 m / s and disperse for 10 min until the system is uniform and stable to obtain the A11 component resin;

[0091] (4) The curing agent of component B11 is hydrophilic HDI polyisocyanate.

[0092] A11 resin and B11 curing agent were weighed in a mass ratio of 1:0.15, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 80 μm.

[0093] Comparative Example 5: A temperature-controlled, anti-cracking protective coating containing only large Janus particle fillers, wherein the A12 component resin and the B12 component curing agent are prepared as follows:

[0094] (1) Weigh 71 parts of polyurethane resin and 22 parts of Janus silica particles with amino groups and dodecyl groups, wherein the particle size of the fillers is 40-80 μm, and disperse and mix them in a high-speed disperser at 55°C and a linear speed of 10 m / s for 15 minutes, followed by ultrasonic treatment for 8 minutes to obtain an Aa-12 mixture;

[0095] (2) 4.65 parts of butanone, 0.8 parts of dispersant, 0.5 parts of antioxidant, 1.3 parts of BASF L0080 and 0.7 parts of fumed silica were weighed and mixed at room temperature. The mixture was pre-dispersed at low speed for 5 minutes using a high-speed disperser. After standing for 10 minutes, the mixture was dispersed at a high speed of 22 m / s for 10 minutes to obtain the Ab-12 mixture.

[0096] (3) Add the Ab-12 mixture to the Aa-12 mixture at a linear speed of 8 m / s and disperse for 10 min until the system is uniform and stable to obtain the A12 component resin;

[0097] (4) Weigh 95 parts of isophorone diisocyanate and 5 parts of butanone, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B12 component curing agent.

[0098] A12 resin and B12 curing agent were weighed in a mass ratio of 1:0.18, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 100 μm.

[0099] Comparative Example 6: A temperature-controlled, crack-resistant protective coating containing only small Janus particle fillers, wherein the A13 component resin and the B13 component curing agent are prepared as follows:

[0100] (1) Weigh 71 parts of polyurethane resin and 22 parts of Janus silica particle filler with amino group and dodecyl group, wherein the filler particle size is all 0.5-2 μm, and disperse and mix them in a high-speed disperser at 55°C and a linear speed of 10 m / s for 15 minutes, followed by ultrasonic treatment for 8 minutes to obtain an Aa-13 mixture;

[0101] (2) 4.65 parts of butanone, 0.8 parts of dispersant, 0.5 parts of antioxidant, 1.3 parts of BASF L0080 and 0.7 parts of fumed silica were weighed and mixed at room temperature. The mixture was pre-dispersed at low speed for 5 minutes using a high-speed disperser. After standing for 10 minutes, the mixture was dispersed at a high speed of 22 m / s for 10 minutes to obtain the Ab-13 mixture.

[0102] (3) Add the Ab-13 mixture to the Aa-13 mixture at a linear speed of 8 m / s and disperse for 10 min until the system is uniform and stable to obtain the A13 component resin;

[0103] (4) Weigh 95 parts of isophorone diisocyanate and 5 parts of butanone, and use a high-speed disperser to disperse and mix for 15 minutes until the system is uniform and stable to obtain the B13 component curing agent.

[0104] A13 resin and B13 curing agent were weighed in a mass ratio of 1:0.18, mixed evenly by mechanical stirring, and then sprayed to obtain a radiation temperature-controlled anti-cracking protective coating with a dry film thickness of 100 μm.

[0105] Comparative Example 7: A thicker high-efficiency temperature-controlling anti-cracking protective coating, the preparation process of its A5 component resin and B5 component curing agent is the same as that of Example 5:

[0106] A5 resin and B5 curing agent were weighed in a mass ratio of 1:0.09, mixed evenly by mechanical stirring, and then sprayed to obtain a temperature-controlled anti-cracking protective coating with a dry film thickness of 150 μm.

[0107] Effect description:

[0108] Performance tests were conducted to compare the high-efficiency temperature-controlling and anti-cracking protective coatings for concrete structures based on Janus particle self-assembly prepared in Examples 1-8 of the present invention with the temperature-controlling coatings prepared in Comparative Examples 1-5.

[0109] Photothermal performance tests were conducted in accordance with GB / T 25261-2018, "Reflective Thermal Insulation Coatings for Buildings." The UV aging test simulated the natural UV aging effects of the product according to GB / T 16422.3-2014, using a Type 2 (UVB-313) lamp (Method C) with an exposure cycle of 1500 hours.

[0110] The relevant test results are sorted into Table 1:

[0111] Table 1 Coating material performance test results

[0112] sample Lightness value L Solar reflectance Near-infrared reflectance Hemispherical emissivity Insulation temperature difference UV aging hemisphere emissivity decreases Example 1 72.3 0.62 0.76 0.93 15.5℃ ＜1% Example 2 73.5 0.63 0.77 0.92 14.8℃ ＜1% Example 3 72.4 0.63 0.76 0.92 15.2℃ ＜1% Example 4 72.8 0.62 0.78 0.93 15.8℃ ＜1% Example 5 73.2 0.63 0.77 0.93 14.7℃ ＜1% Example 6 73.0 0.63 0.77 0.92 14.8℃ ＜1% Example 7 72.2 0.62 0.76 0.94 15.5℃ ＜1% Example 8 72.5 0.63 0.76 0.92 15.0℃ ＜1% Comparative Example 1 75.6 0.60 0.74 0.79 8.3℃ 13% Comparative Example 2 74.3 0.62 0.75 0.83 11.3℃ 2% Comparative Example 3 73.6 0.61 0.75 0.82 10.5℃ ＜1% Comparative Example 4 72.8 0.61 0.74 0.84 10.6℃ ＜1% Comparative Example 5 72.3 0.62 0.74 0.81 11.5℃ ＜1% Comparative Example 6 72.5 0.61 0.75 0.82 10.9℃ ＜1% Comparative Example 7 72.6 0.62 0.74 0.83 12.7℃ ＜1%

[0113] The data in Table 1 demonstrates that the thermal performance of the temperature-control coating materials prepared in Examples 1-8 is significantly superior to that of the comparative examples, particularly in terms of significantly improved near-infrared reflectance and hemispherical emissivity. This significantly improves the thermal insulation temperature difference and significantly enhances the temperature control effect compared to the comparative examples, which is of great significance for temperature control and energy conservation in outdoor exposed structures. Furthermore, due to the robust and reliable construction of the surface micro-nanostructure and the external coating with a highly durable resin and curing agent system, the thermal performance of the coating is highly durable and reliable over long-term use.

[0114] The commercially available temperature-control coating of Comparative Example 1 is mainly achieved through reflection under high brightness, and the surface lacks the corresponding micro-nano structure. Therefore, the radiation performance is weak, the overall temperature control performance is poor, and it is more sensitive to surface contamination and aging, and the durability is poor. Comparative Examples 2-4 use conventional titanium dioxide fillers, hydrophilic particle fillers, and hydrophobic particle fillers as raw materials. Compared with the examples, their sunlight reflection performance is relatively close, but because these three fillers cannot produce regular arrangement and distribution, the surface of the dried film layer cannot form a micro-nano structure with a regular distribution. Therefore, their radiation performance is quite different and the temperature control performance is significantly reduced. Comparative Examples 5-6 use only large-sized or small-sized Janus particle fillers. The inter-particle interaction force of a single large-sized Janus particle filler is significantly weak, the self-assembly process is slow and it is easy to agglomerate, so it cannot form a regular structure during the drying process. The self-assembly structure of a single small-sized Janus particle is less regular, and due to its small size, it cannot have a significant impact on the surface structure, so the performance is not significantly improved. Comparative Example 5 used the raw materials of Example 5, but due to the thick coating thickness, the micro-nano structure formed by the Janus particle filler could not be distributed on the coating surface and was wrapped in the coating, so there was no obvious effect.

[0115] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A high-efficiency temperature-controlling and anti-cracking protective coating for concrete structures, characterized in that The surface functional coating is obtained by mixing component A resin and component B curing agent; wherein the component A resin is prepared from base resin, special filler, solvent, functional additive, color paste and rheology regulator, wherein the special filler is an amphiphilic Janus particle filler having a hydrophilic group on one side of the surface and a hydrophobic group on the other side, and its particle size distribution is that small particles in the range of 0.5μm-2μm account for 15%-25% by mass, and large particles in the range of 40μm-80μm account for 75%-85% by mass; the component B curing agent is prepared from curing agent and solvent; wherein the mass ratio of the component A resin to the component B curing agent is 1:(0.08-0.22).

2. A high-efficiency temperature-controlling and anti-cracking protective coating according to claim 1, characterized in that The preparation process of the amphiphilic Janus particle filler is as follows: (1) fully oxidizing the surface of particles of suitable particle size and then modifying them with an aminosilane coupling agent; (2) dispersing the modified particles at high speed in a paraffin / water emulsion under high temperature conditions and fixing them by cooling; (3) grafting hydrophobic groups on the surface of the fixed particles; (4) eluting the paraffin and grafting hydrophilic groups on the remaining part of the particle surface; wherein the particles are at least one of silica particles, ferrosoferric oxide particles, silicon nitride particles, silicon carbide particles, polystyrene particles and polyvinyl pyrrolidone particles; wherein the hydrophilic group is at least one of a carboxyl group, an amino group and a sulfonic acid group; and wherein the hydrophobic group is at least one of a methyl group, an ethyl group, a propyl group, a phenyl group and a long-chain alkane group with 4 to 12 carbon atoms.

3. The high-efficiency temperature-controlling and anti-cracking protective coating according to claim 1, characterized in that In the resin of component A, the contents of base resin, special filler, solvent, functional additive, pigment and rheology modifier are 50-72%, 22-33%, 3-10%, 0.5-3.5%, 0.1-2.5% and 0.5-2.0% respectively, based on the total mass of component A; wherein the base resin is at least one of solvent-based or water-based silicone resin, acrylate-modified silicone resin, fluororesin, fluorocarbon resin, polyurethane resin and acrylic acid-modified polyurethane resin; wherein the solvent is petroleum ether, benzene, toluene, xylene, At least one of hexane, chloroform, acetone, butanone, ethanol, propanol, n-butanol, ethyl acetate, butyl acetate, dimethylformamide, dimethyl sulfoxide and water; wherein the functional additive is at least one of a dispersant, a defoamer, a leveling agent, a UV absorber, an antioxidant and a mildewcide; wherein the pigment is at least one of water-based or solvent-based black, brown and gray color pastes from Clariant, Degussa, CPS, BASF and Shiming; wherein the rheology modifier is at least one of bentonite, hydrated magnesium silicate, fumed silica, polyamide wax and polyethylene wax.

4. The high-efficiency temperature-controlling and anti-cracking protective coating according to claim 1, characterized in that In the curing agent of component B, the contents of the curing agent and the solvent are 85%-100% and 0-15% respectively, based on the total mass of component B; the curing agent is at least one of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane dimethylene diisocyanate, toluene diisocyanate trimer, hexamethylene diisocyanate trimer, hydrophilic HDI polyisocyanate and hydrophilic modified IPDI polyisocyanate; and the solvent is at least one of petroleum ether, benzene, toluene, xylene, n-hexane, chloroform, acetone, butanone, ethanol, propanol, n-butanol, ethyl acetate, butyl acetate, dimethylformamide, dimethyl sulfoxide and water.

5. The high-efficiency temperature-controlling and anti-cracking protective coating according to claim 1, characterized in that The preparation method of the A component resin and the B component curing agent comprises the following steps: (1) Weighing appropriate amounts of each component, the base resin and the special filler were dispersed and mixed using a high-speed disperser at 40-60°C and a linear speed of 6-10 m / s for 15 min, followed by ultrasonic treatment for 4-10 min to obtain a mixture Aa; (2) The solvent, functional additive, color paste and rheology modifier were mixed at room temperature, pre-dispersed at low speed for 5 minutes using a high-speed disperser, allowed to stand for 10 minutes, and then dispersed at a linear speed of 18-24 m / s for 10 minutes to obtain the Ab mixture; (3) adding the Ab mixture to the Aa mixture at a linear speed of 6-10 m / s and dispersing for 5-10 min until the system is homogeneous and stable to obtain the A component resin; (4) The curing agent and solvent are dispersed and mixed using a high-speed disperser for 15 minutes until the system is uniform and stable to obtain the curing agent component B.

6. The high-efficiency temperature-controlling and anti-cracking protective coating according to claim 1, characterized in that The dry film thickness after construction is 40-100μm, and the construction method can be any one of spraying, dipping, roller coating and brushing.

7. Use of the high-efficiency temperature-controlling and anti-cracking protective coating according to claim 1 as a surface temperature-controlling material for houses, cold storages, storage tanks, roadbeds, bridges, tracks, and small components.