High-efficiency long-service-life organic silicon aerogel building heat insulation coating and preparation method thereof

Abstract

The invention relates to the field of building heat insulation coatings, and discloses a high-efficiency long-life organosilicon aerogel building heat insulation coating and a preparation method thereof, the high-efficiency long-life organosilicon aerogel building heat insulation coating comprises the following components: an organosilicon resin matrix, a multi-stage heat insulation composite filler, a curing agent and an auxiliary agent; the multi-stage heat-insulation composite filler is prepared from hydrophobic modified nano silicon dioxide aerogel particles and hollow glass beads, the hydrophobic modified nano silicon dioxide aerogel particles are subjected to surface modification treatment through a silane coupling agent, and stable chemical bonding is formed between the hydrophobic modified nano silicon dioxide aerogel particles and an organic silicon resin matrix; therefore, a micro-scale and nano-scale continuous and stable multi-stage pore heat insulation network is constructed in the coating; the mass ratio of the hydrophobic modified nano silicon dioxide aerogel particles to the hollow glass beads is (1: 0.5)-(1: 2); the heat conductivity coefficient of the coating is not higher than 0.025 W / m.K. Compared with the prior art, the thermal insulation coating has the advantage that the problem that the thermal insulation coating in the prior art is difficult to give consideration to long-acting thermal insulation performance and durability is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building thermal insulation coatings, in particular to a high-efficiency long-service-life organic silicon aerogel building thermal insulation coating and a preparation method thereof. BACKGROUND

[0002] The heat loss of building envelope is the main part of building energy consumption, and reducing this part of energy consumption is of great significance to achieve the goal of energy saving and emission reduction. Traditional building thermal insulation materials, such as polystyrene foam and rock wool, have poor weather resistance, insufficient fire resistance, and are prone to water absorption and dampness, which affects their long-term thermal insulation effect and service life.

[0003] Aerogel materials are considered ideal thermal insulation materials due to their extremely low thermal conductivity. However, there are many challenges in applying nanometer aerogels to building coatings: nanometer particles are prone to agglomeration in the resin matrix and are difficult to disperse uniformly; the interfacial bonding force between aerogel and matrix is weak, affecting the mechanical properties and stability of the coating; the nanometer porous structure of the coating is easily degraded when exposed to ultraviolet light, heat and humidity for a long time outdoors, resulting in a significant decrease in thermal insulation performance.

[0004] In the prior art, although some research has attempted to combine aerogel with organic silicon resin, it often focuses on a single dispersion process or simple physical blending, and has not fundamentally solved the problem of the synergy between the dispersion stability of nanofiller, interfacial bonding force and long-term weather resistance. Therefore, developing a building thermal insulation coating that can build a stable microstructure and has low thermal conductivity and excellent durability is a technical problem that needs to be solved in the field. SUMMARY

[0005] (I) Technical problem to be solved

[0006] The technical problem to be solved by the present application is to provide a high-efficiency long-service-life organic silicon aerogel building thermal insulation coating and a preparation method thereof, in order to solve the problem that existing thermal insulation coatings cannot simultaneously achieve long-term thermal insulation performance and durability.

[0007] (II) Technical solution

[0008] To solve the above technical problems, the technical solution provided by the present application is: a high-efficiency long-service-life organic silicon aerogel building thermal insulation coating, characterized in that it comprises the following components: an organic silicon resin matrix, a multi-stage thermal insulation composite filler, a curing agent and an additive.

[0009] The multi-stage thermal insulation composite filler is composed of hydrophobically modified nanometer silica aerogel particles and hollow glass microspheres, wherein the hydrophobically modified nanometer silica aerogel particles are surface modified by a silane coupling agent to form stable chemical bonds with the organic silicon resin matrix, thereby building a micro- and nano-scale continuous and stable multi-stage porous thermal insulation network in the coating.

[0010] The mass ratio of the hydrophobic modified nanosilica aerogel particles to the hollow glass microbeads is 1:0.5 to 1:2.

[0011] The thermal conductivity of the coating is not higher than 0.025 W / m·K, the change rate of the thermal conductivity after the ultraviolet aging test is less than 5%, and the adhesion is not less than level 1.

[0012] The preparation method of the high-efficiency long-life organic silicon aerogel building thermal insulation coating comprises the following steps:

[0013] S1, preparation of hydrophobic modified nanogel particles: surface modification reaction of nanosilica aerogel particles and silane coupling agent in a solvent, reaction temperature is 50-80℃, reaction time is 2-4 hours, then vacuum drying to obtain hydrophobic modified nanosilica aerogel particles;

[0014] S2, preparation of multi-stage thermal insulation composite filler: mixing the hydrophobic modified nanosilica aerogel particles obtained in step S1 with hollow glass microbeads according to a mass ratio of 1:0.5 to 1:2 to form a multi-stage thermal insulation composite filler;

[0015] S3, preparation of coating composition: mixing organic silicon resin matrix, multi-stage thermal insulation composite filler obtained in step S2, curing agent and auxiliary agent, and processing by mechanical stirring and ultrasonic auxiliary dispersion to form chemical bonding between the hydrophobic modified nanosilica aerogel particles and the organic silicon resin matrix, and to construct a multi-stage pore thermal insulation network to obtain the building thermal insulation coating.

[0016] As an improvement, the organic silicon resin matrix is a hydrolyzed prepolymer of methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES), tetraethyl orthosilicate (TEOS), or a copolymer thereof.

[0017] As an improvement, the silane coupling agent is one or more of KH-550, KH-560, and KH-570.

[0018] As an improvement, the average particle size of the hollow glass microbeads is 10-100 microns.

[0019] As an improvement, the auxiliary agent includes at least one of a dispersing agent, a defoaming agent, and a light stabilizer; the dispersing agent is an anionic polyacrylic acid sodium salt, and the solvent in the defoaming step S1 is a mixed solvent of ethanol and deionized water, wherein the mass ratio of ethanol to deionized water is 5:1 to 8:1.

[0020] As an improvement, the rotation speed of the mechanical stirring in step S3 is 1000-3000 rpm for 10-30 minutes; the power of the ultrasonic auxiliary dispersion is 300-500 W for 5-15 minutes.

[0021] As an improvement, the curing agent is dibutyl tin dilaurate, and the addition amount is 1% to 2% of the mass of the silicone resin matrix.

[0022] As an improvement, the coating further comprises an infrared light shielding agent, the infrared light shielding agent is at least one of iron oxide and titanium dioxide, and the addition amount is 1% to 5% of the total mass of the coating.

[0023] (III) Beneficial effects

[0024] Compared with the prior art, the present application has the following advantages:

[0025] (1) By compounding nano-sized silica aerogel with micro-sized hollow glass microbeads, a composite thermal insulation system spanning multiple scales is formed. The aerogel itself has extremely low solid-state and gas-phase thermal conductivity, and the hollow microbeads effectively block the heat radiation path. The two work together to build a high-efficiency thermal insulation barrier, making the coating have extremely low thermal conductivity.

[0026] (2) The surface of the nano-aerogel particles is hydrophobically modified, which not only improves the compatibility with the silicone matrix, but more importantly, enhances the interfacial bonding between the filler and the matrix through chemical bonding. This effectively prevents the shedding and migration of nano-particles during service, ensuring the long-term structural stability of the porous thermal insulation network. DETAILED DESCRIPTION

[0027] The following further describes the application content of the present application in conjunction with specific embodiments, but this should not be understood as limiting the scope of the subject matter of the present application to only the following examples.

[0028] Example One

[0029] The high-efficiency long-life silicone aerogel building thermal insulation coating comprises the following components: a silicone resin matrix, a multi-stage thermal insulation composite filler, a curing agent, and an auxiliary agent. The silicone resin matrix is a hydrolyzed prepolymer of methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES), and tetraethyl orthosilicate (TEOS) or a copolymer thereof. The auxiliary agent includes a dispersing agent, which is an anionic polyacrylic acid sodium salt. The curing agent is dibutyl tin dilaurate, and the addition amount is 1% of the mass of the silicone resin matrix.

[0030] The multi-stage thermal insulation composite filler is composed of hydrophobically modified nano-silica aerogel particles and hollow glass microbeads. The average particle size of the hollow glass microbeads is 10 microns. The hydrophobically modified nano-silica aerogel particles are surface-modified by a silane coupling agent to form stable chemical bonding with the silicone resin matrix, thereby constructing a continuous and stable multi-stage porous thermal insulation network at the micro and nano scales in the coating. The silane coupling agent is KH-550.

[0031] The mass ratio of the hydrophobic modified nanosilica aerogel particles to hollow glass microspheres is 1:0.5;

[0032] The thermal conductivity of the coating is not higher than 0.025 W / m·K, the change rate of thermal conductivity after ultraviolet aging test is less than 5%, and the adhesion is not less than 1 level, the coating further comprises an infrared light shielding agent, the infrared light shielding agent is iron oxide, and the addition amount is 1% of the total mass of the coating.

[0033] The preparation method of the high-efficiency long-life silicone aerogel building thermal insulation coating comprises the following steps:

[0034] S1, preparation of hydrophobic modified nanometer aerogel particles: surface modification reaction of nanosilica aerogel particles and silane coupling agent in a solvent, reaction temperature is 50℃, reaction time is 2 hours, and then vacuum drying to obtain hydrophobic modified nanosilica aerogel particles, the solvent is a mixed solvent of ethanol and deionized water, and the mass ratio of ethanol to deionized water is 5:1;

[0035] S2, preparation of multi-stage thermal insulation composite filler: mixing the hydrophobic modified nanosilica aerogel particles obtained in step S1 with hollow glass microspheres according to a mass ratio of 1:0.5 to form a multi-stage thermal insulation composite filler;

[0036] S3, preparation of coating composition: mixing silicone resin matrix, multi-stage thermal insulation composite filler obtained in step S2, curing agent and auxiliary agent, and through mechanical stirring and ultrasonic auxiliary dispersion treatment, the hydrophobic modified nanosilica aerogel particles and the silicone resin matrix form chemical bonding to construct a multi-stage pore thermal insulation network, and the building thermal insulation coating is prepared, the rotating speed of the mechanical stirring is 1000 rpm, and the time is 10 minutes; the power of the ultrasonic auxiliary dispersion is 300 W, and the time is 5 minutes.

[0037] Example two

[0038] The high-efficiency long-life silicone aerogel building thermal insulation coating comprises the following components: silicone resin matrix, multi-stage thermal insulation composite filler, curing agent and auxiliary agent, the silicone resin matrix is a hydrolyzed prepolymer of methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES) and tetraethyl orthosilicate (TEOS), or a copolymer thereof, the auxiliary agent comprises a defoaming agent; the defoaming agent is a polysiloxane defoaming agent, and the curing agent is dibutyltin dilaurate, and the addition amount is 1.5% of the mass of the silicone resin matrix;

[0039] The multi-stage thermal insulation composite filler is composed of hydrophobic modified nano-silica aerogel particles and hollow glass microspheres, the average particle size of the hollow glass microspheres is 50 microns, wherein the hydrophobic modified nano-silica aerogel particles are surface modified by a silane coupling agent to form stable chemical bonding with a silicone resin matrix, thereby constructing a micro- and nano-scale continuous stable multi-stage pore thermal insulation network in the coating, and the silane coupling agent is KH-550 or KH-560.

[0040] The mass ratio of the hydrophobic modified nano-silica aerogel particles to the hollow glass microspheres is 1:1.

[0041] The thermal conductivity of the coating is not higher than 0.025 W / m·K, the change rate of the thermal conductivity after ultraviolet aging test is less than 5%, and the adhesion is not less than level 1, the coating further comprises an infrared light shielding agent, the infrared light shielding agent is titanium dioxide, and the addition amount is 3% of the total mass of the coating.

[0042] The preparation method of the efficient long-life silicone aerogel building thermal insulation coating comprises the following steps:

[0043] S1, preparation of hydrophobic modified nano-aerogel particles: surface modification reaction of nano-silica aerogel particles and silane coupling agent in a solvent, reaction temperature is 60℃, reaction time is 3 hours, and then vacuum drying to obtain hydrophobic modified nano-silica aerogel particles, the solvent is a mixed solvent of ethanol and deionized water, and the mass ratio of ethanol to deionized water is 6:1;

[0044] S2, preparation of multi-stage thermal insulation composite filler: mixing the hydrophobic modified nano-silica aerogel particles obtained in step S1 with hollow glass microspheres according to a mass ratio of 1:1 to form a multi-stage thermal insulation composite filler;

[0045] S3, preparation of coating composition: mixing a silicone resin matrix, the multi-stage thermal insulation composite filler obtained in step S2, a curing agent and an additive, and treating by mechanical stirring and ultrasonic auxiliary dispersion to form chemical bonding between the hydrophobic modified nano-silica aerogel particles and the silicone resin matrix, and constructing a multi-stage pore thermal insulation network to prepare the building thermal insulation coating, the rotation speed of the mechanical stirring is 2000 rpm, and the time is 20 minutes; the power of the ultrasonic auxiliary dispersion is 400 W, and the time is 10 minutes.

[0046] Example Three

[0047] The high-efficiency long-life silicone aerogel building thermal insulation coating comprises the following components: a silicone resin matrix, a multi-stage thermal insulation composite filler, a curing agent and an additive, the silicone resin matrix is a hydrolyzed prepolymer of methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES) and tetraethyl orthosilicate (TEOS) or a copolymer thereof, and the additive comprises a light stabilizer; the light stabilizer is a hindered amine light stabilizer, and the curing agent is dibutyltin dilaurate, and the addition amount is 2% of the mass of the silicone resin matrix;

[0048] The multi-stage thermal insulation composite filler is composed of hydrophobically modified nanosilica aerogel particles and hollow glass microbeads, the average particle size of the hollow glass microbeads is 100 microns, wherein the hydrophobically modified nanosilica aerogel particles are subjected to surface modification treatment by a silane coupling agent to form stable chemical bonds with the silicone resin matrix, thereby constructing a micro- and nanoscale continuous stable multi-stage porous thermal insulation network in the coating, and the silane coupling agent is KH-560 or KH-570;

[0049] The mass ratio of the hydrophobically modified nanosilica aerogel particles to the hollow glass microbeads is 1:2;

[0050] The thermal conductivity of the coating is not higher than 0.025 W / m·K, the change rate of the thermal conductivity after the ultraviolet aging test is less than 5%, and the adhesion is not less than level 1, the coating further comprises an infrared light shielding agent, the infrared light shielding agent is iron oxide or titanium dioxide, and the addition amount is 5% of the total mass of the coating.

[0051] The preparation method of the high-efficiency long-life silicone aerogel building thermal insulation coating comprises the following steps:

[0052] S1, preparation of hydrophobically modified nanogel particles: nanosilica aerogel particles and a silane coupling agent are subjected to surface modification reaction in a solvent, the reaction temperature is 80°C, the reaction time is 4 hours, and then vacuum drying is performed to obtain hydrophobically modified nanosilica aerogel particles, and the solvent is a mixed solvent of ethanol and deionized water, wherein the mass ratio of ethanol to deionized water is 8:1;

[0053] S2, preparation of a multi-stage thermal insulation composite filler: the hydrophobically modified nanosilica aerogel particles obtained in step S1 are mixed with hollow glass microbeads at a mass ratio of 1:2 to form a multi-stage thermal insulation composite filler;

[0054] S3, preparation of the coating composition: the silicone resin matrix, the multi-stage thermal insulation composite filler obtained in step S2, the curing agent and the auxiliary agent are mixed, the hydrophobic modified nanosilica aerogel particles are chemically bonded with the silicone resin matrix through mechanical stirring and ultrasonic assisted dispersion treatment, a multi-stage porous thermal insulation network is constructed, and the building thermal insulation coating is prepared.

[0055] The application has been shown and described with reference to embodiments thereof, but it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made thereto without departing from the spirit and scope of the application, the scope of which is defined by the appended claims and their equivalents, in general, if a person skilled in the art is inspired by it, without departing from the purpose of the application, without being creatively designed, similar structure and embodiments of the technical scheme should belong to the protection scope of the application.

Claims

1. A high-efficiency, long-life silicone aerogel building insulation coating, characterized in that: It includes the following components: silicone resin matrix, multi-level thermal insulation composite filler, curing agent and additives; The multi-level thermal insulation composite filler is composed of hydrophobically modified nano-silica aerogel particles and hollow glass microspheres. The hydrophobically modified nano-silica aerogel particles are surface modified by silane coupling agent to form a stable chemical bond with the organosilicon resin matrix, thereby constructing a continuous and stable multi-level porous thermal insulation network at the micro and nanoscale in the coating. The mass ratio of the hydrophobically modified nano-silica aerogel particles to hollow glass microspheres is 1:0.5 to 1:2; The coating has a thermal conductivity of no more than 0.025 W / m·K, a thermal conductivity change rate of less than 5% after ultraviolet aging test, and an adhesion grade of no less than 1.

2. The preparation method of the high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 1, characterized in that, Includes the following steps: S1. Preparation of hydrophobic modified nano-aerogel particles: Nano-silica aerogel particles are surface modified with silane coupling agent in a solvent at a reaction temperature of 50-80℃ for 2-4 hours, followed by vacuum drying to obtain hydrophobic modified nano-silica aerogel particles. S2. Preparation of multi-level thermal insulation composite filler: The hydrophobic modified nano silica aerogel particles obtained in step S1 are mixed with hollow glass microspheres at a mass ratio of 1:0.5 to 1:2 to form a multi-level thermal insulation composite filler. S3. Preparation of coating composition: The organosilicon resin matrix, the multi-level heat insulation composite filler obtained in step S2, the curing agent and the additives are mixed and dispersed by mechanical stirring and ultrasonic-assisted dispersion treatment, so that the hydrophobic modified nano silica aerogel particles form chemical bonds with the organosilicon resin matrix to construct a multi-level porous heat insulation network, and the building heat insulation coating is obtained.

3. The high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 1, characterized in that: The silicone resin matrix is ​​a hydrolyzed prepolymer of methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES), tetraethyl orthosilicate (TEOS), or a copolymer thereof.

4. The high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 1, characterized in that: The silane coupling agent is one or more of KH-550, KH-560, and KH-570.

5. The high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 1, characterized in that: The hollow glass microspheres have an average particle size of 10-100 micrometers.

6. The high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 1, characterized in that: The additives include at least one of dispersant, defoamer, and light stabilizer; the dispersant is anionic sodium polyacrylate, the defoamer is a polysiloxane defoamer, and the light stabilizer is a hindered amine light stabilizer.

7. The preparation method of the high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 2, characterized in that, The solvent mentioned in step S1 is a mixed solvent of ethanol and deionized water, wherein the mass ratio of ethanol to deionized water is 5:1 to 8:

1.

8. The preparation method of the high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 2, characterized in that, In step S3, the mechanical stirring speed is 1000-3000 rpm and the time is 10-30 minutes; the ultrasonic-assisted dispersion power is 300-500W and the time is 5-15 minutes.

9. The preparation method of the high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 2, characterized in that, The curing agent is dibutyltin dilaurate, and the amount added is 1% to 2% of the mass of the silicone resin matrix.

10. The preparation method of the high-efficiency, long-life organosilicon aerogel building thermal insulation coating according to claim 1, characterized in that, The coating also includes an infrared shading agent, which is at least one of iron oxide and titanium dioxide, and is added at a rate of 1% to 5% of the total mass of the coating.