Preparation method of UV-cured thermal insulation coating

Abstract

The invention discloses a preparation method of a UV-cured thermal insulation coating, and relates to the technical field of coatings. The preparation method comprises the following steps: firstly, preparing a UV curing coating by taking 2-ethyl-2-(mercaptomethyl)-1, 3-propanedithiol and pentaerythritol triallyl ether as raw materials, and then adding a modified phase change microcapsule material as a thermal insulation auxiliary agent; the polyfunctional group raw material can form a highly cross-linked polymer network structure, so that the mechanical property of the cured coating is improved; an oxidized foam metal loaded sugar alcohol mixture is used as a core material of the phase-change microcapsule, p-fluorocinnamyl chloride doped modified polyamide is used as a shell material of the phase-change microcapsule, then the modified phase-change microcapsule material is prepared by adopting an interfacial polymerization method, and the modified phase-change material can absorb or release heat more quickly, so that the heat preservation effect is improved, and the service life of the phase-change microcapsule is prolonged. The surface of the fluorocinnamyl chloride modified phase change microcapsule material contains double bonds and can participate in a curing reaction to be directly bonded with a resin network, so that the interfacial strength is enhanced. According to the prepared UV curing thermal insulation coating, the thermal insulation effect of the coating is improved.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a method for preparing a UV-curable thermal insulation coating. Background Technology

[0002] With increasing global awareness of environmental protection, the coatings industry is moving towards sustainability. UV coatings, due to their environmental friendliness, convenience, and cost-effectiveness, have been widely used in modern society. Ultraviolet (UV) curing coatings, as a type of radiation-cured coating, specifically refer to new types of coatings that can rapidly cross-link and cure into a film under light conditions. Compared to traditional solvent-based coatings, UV-cured coatings exhibit many advantages: fast curing speed, no volatile organic solvents, low energy consumption, high cost-effectiveness, and support for automated production processes, thus being considered a coating choice that aligns with green and environmentally friendly principles.

[0003] Faced with the ever-increasing energy consumption and the impending depletion of traditional fossil fuels, the building sector, as a major energy consumer, exhibits particularly high energy consumption during heating and cooling operations. To address this challenge, reducing energy consumption and greenhouse gas emissions, and achieving sustainable development goals, improving the energy efficiency of buildings has become an urgent issue. Against this backdrop, thermal insulation coatings, with their effective heat transfer barrier properties, have become one of the key technological means to reduce energy loss during building use.

[0004] Therefore, developing a new type of coating that combines UV curing technology and thermal insulation function is particularly important. This UV-cured thermal insulation coating will not only inherit the environmentally friendly characteristics shared by both, but will also further expand its application potential in improving building energy efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing a UV-curable thermal insulation coating to solve the problems existing in the prior art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a UV-curable thermal insulation coating, wherein the UV-curable thermal insulation coating is prepared by adding thermal insulation additives, diluents, photoinitiators, leveling agents and solvents to 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol and pentaerythritol triallyl ether as raw materials; The thermal insulation agent is a modified phase change microcapsule material; the modified phase change microcapsule material is prepared by interfacial polymerization using an oxide foam metal-supported sugar alcohol mixture as the core material and fluorocinnamoyl chloride-modified polyamide as the shell material.

[0007] Furthermore, the diluent is one of DVE-3, CHVE, HBVE, or DDVE.

[0008] Furthermore, the photoinitiator is one of 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 2,2-dimethoxy-2-phenylacetophenone, or 2-hydroxy-4-methoxybenzophenone.

[0009] Furthermore, the leveling agent is one of BYK-UV3500, BYK-UV3530, or BYK-UV3570.

[0010] Furthermore, a method for preparing a UV-curable thermal insulation coating includes the following preparation steps: (1) Place the sugar alcohol mixture in a drying oven and dry it at 100~105℃ for 8~10h. Then place it in a sealed box and heat it to 200℃. Keep it at the temperature for 1~2h. After taking it out and cooling it to room temperature, grind it for 15min at 250r / min using a planetary ball mill. After passing it through a 150-mesh sieve, you will get the pretreated sugar alcohol mixture. (2) Dissolve the pretreated sugar alcohol mixture in 5 to 10 times the mass of the pretreated sugar alcohol mixture in deionized water, add 0.8 to 1.0 times the mass of the pretreated sugar alcohol mixture in oxidized foam metal, and then stir at 80 to 100°C and 300 to 400 r / min until the deionized water is completely evaporated. After drying at 100°C for 1.0 to 1.5 h, the modified phase change material is obtained. (3) Aqueous phase: Polyethylene glycol and deionized water are mixed at a mass ratio of 0.05~0.08:1, and modified phase change material is added at a volume of 0.03~0.05 times that of the mixture. The mixture is stirred at 500~600 r / min for 30~60 min to obtain the aqueous phase. Oil phase: Mix p-fluorocinnamyl chloride and terephthaloyl chloride at a molar ratio of 0.1~0.3:1, then add 0.01~0.03 times the mass of terephthaloyl chloride and Tween 80 to obtain a mixture. Dissolve the mixture in an organic solvent and stir at 500~600 r / min for 30~60 min to obtain the oil phase. Emulsification: At 50℃ and 800~1000r / min, the oil phase is added to the aqueous phase and stirred for 20~40min to obtain a stable emulsion. The volume ratio of the oil phase to the aqueous phase is 1:3. Encapsulation: At room temperature and 600 r / min, an aqueous solution of amine was added to a stable emulsion and reacted for 15-30 min. After filtration and washing, the modified phase change microcapsule material was obtained. (4) By mass percentage, 20-35% 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol, 20-35% pentaerythritol triallyl ether, 3-5% modified phase change microcapsule material, 5-10% diluent, 1-5% photoinitiator, 0.3-1% leveling agent and 20-30% solvent are mixed to prepare UV-curable thermal insulation coating.

[0011] Furthermore, in step (2), the oxidized foam metal is obtained by washing and drying the foam metal with deionized water, heat-treating it in an air atmosphere at 500~800℃ for 3~5 hours, and then naturally cooling it to room temperature. The foam metal is one of foam iron, foam nickel, or foam copper.

[0012] Furthermore, in step (3), the organic solvent is prepared by mixing cyclohexane and chloroform in a 3:2 ratio.

[0013] Furthermore, in step (3), the aqueous solution of the amine is prepared by mixing 1,6-hexanediamine and diethylenetriamine in a molar ratio of 1:1 to obtain a mixed solution, and then dissolving the mixed solution in deionized water at a mass of 2 to 3 times that of the mixed solution.

[0014] Furthermore, the molar ratio of 1,6-hexanediamine, diethylenetriamine, and terephthaloyl chloride is 1.0~1.1:1.0~1.1:1.

[0015] Furthermore, in step (3), the washing process involves alternating between deionized water and ethanol 2-3 times.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are: This invention uses 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol and pentaerythritol triallyl ether as raw materials to prepare UV-curable coatings, and then adds modified phase change microcapsule materials as thermal insulation additives to improve the thermal insulation effect of the coatings.

[0017] First, a UV-curable coating was prepared using 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol and pentaerythritol triallyl ether as raw materials. Ethyl-2-(mercaptomethyl)-1,3-propanedithiol and pentaerythritol triallyl ether undergo a thiol-ene click reaction under ultraviolet light, resulting in rapid curing and the formation of a solid coating film within a short time. This improves production efficiency, reduces the evaporation time of the coating during curing, and minimizes environmental impact. Simultaneously, the thermal insulation additive provides double bonds on the surface of the fluorocinnamoyl chloride-modified phase change microcapsule material, which also provides active sites during UV curing. It can directly bond with the resin network through the click reaction of thioolefins to form a "microcapsule-matrix" covalent connection, which enhances the interfacial strength and further improves the mechanical properties of the coating after curing. In addition, 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol contains multiple thiol groups, which can form a highly cross-linked polymer network structure. The dense polymer network can effectively prevent external corrosive substances, such as moisture, oxygen, acids and alkalis, from penetrating into the coating film, thereby protecting the substrate from corrosion. The pentaerythritol skeleton provides rigidity, while the ethyl branches and thioether bonds impart toughness and prevent brittle cracking.

[0018] Secondly, an oxide foam metal-loaded sugar alcohol mixture was used as the core material of the phase change microcapsules, and fluorocinnamoyl chloride-modified polyamide was used as the shell material. Then, the modified phase change microcapsule material was prepared using interfacial polymerization. This modified microcapsule material was then added to the above raw materials as a thermal insulation agent to prepare a UV-curable thermal insulation coating. The oxide foam metal surface has oxide active sites that can form hydrogen bonds with sugar alcohol compounds, thus more firmly loading the sugar alcohol compounds. Furthermore, the foam metal has good thermal conductivity, which effectively improves the low thermal conductivity of the sugar alcohol mixture after loading, enhancing its thermal conductivity and heat transfer efficiency during the phase change process. When the ambient temperature changes, the modified phase change material... The material can absorb or release heat more quickly, achieving a more efficient phase change and improving the thermal insulation effect; the encapsulation of polyamide resin can effectively prevent the phase change material from direct contact with the environment, playing a protective role, and at the same time, it can also prevent the leakage of the phase change material during use, further improving the thermal insulation performance of the coating; introducing fluorine atoms into the polyamide shell, the strong hydrophobicity of fluorine atoms can significantly reduce the water absorption rate of the shell, reduce the erosion of the phase change material by water penetration, avoid the microcapsules from rupturing due to moisture absorption and expansion, improve the coating effect of the polyamide shell, extend the service life of the microcapsule material, and the fluorine groups can reduce the surface energy of the shell, reduce the adhesion between microcapsules, and improve its dispersibility in UV-cured coatings. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] To more clearly illustrate the method provided by the present invention, the following embodiments are provided in detail. The test methods for various indicators of the UV-cured thermal insulation coating prepared in the following embodiments are as follows: The UV-curable coatings prepared according to the embodiments and comparative examples of the present invention are subjected to the following processes: The process sequence is as follows: substrate cleaning → coating dilution → spraying → IR baking → UV curing. Specific process parameters are: spray the UV-curable thermal insulation coating onto the metal surface and bake at 70℃ for 3-5 minutes; then apply an energy of 1000-2100 mJ / cm². 2 The UV curing machine was used to cure the coating, and the resulting coating was subjected to the following performance tests.

[0021] Adhesion: The adhesion of UV-cured thermal insulation coatings prepared by the same mass of the examples and comparative examples was tested according to GB / T9286-1998 "Cross-cut test method for paint and varnish film".

[0022] Hardness: The hardness of the UV-cured thermal insulation coatings prepared by the same mass of the examples and comparative examples was tested according to GB / T6739-1996 "Pencil Hardness Test Method".

[0023] Thermal conductivity: The thermal conductivity of the UV-cured thermal insulation coatings prepared by the same mass of the examples and comparative examples was tested in accordance with GB / T17371-2008 "Silicate Composite Thermal Insulation Coatings".

[0024] Example 1 A method for preparing a UV-curable thermal insulation coating includes the following preparation steps: (1) After cleaning and drying PPI40 nickel foam with deionized water, heat-treat it at 500°C for 3 hours in air atmosphere and then cool it naturally to room temperature to obtain nickel foam oxide. (2) Erythritol and mannitol were placed in a drying oven at a mass ratio of 1:1 and dried at 100°C for 8 hours. Then, they were placed in a sealed box and heated to 200°C for 1 hour. After being taken out and naturally cooled to room temperature, they were ground in a planetary ball mill at a speed of 250 r / min for 15 minutes. After passing through a 150-mesh sieve, a pretreated sugar alcohol mixture was obtained. (3) Dissolve the pretreated sugar alcohol mixture in 5 times the mass of the pretreated sugar alcohol mixture in deionized water, add 0.8 times the mass of the pretreated sugar alcohol mixture in oxidized foam metal, and then stir at 80℃ and 300r / min until the deionized water is completely evaporated. After drying at 100℃ for 1.0h, the modified phase change material is obtained. (4) Aqueous phase: Polyethylene glycol 6000 and deionized water were mixed at a mass ratio of 0.05:1, and modified phase change material was added at a volume of 0.03 times that of the mixture. The mixture was stirred at 500 r / min for 30 min to obtain the aqueous phase. Oil phase: p-Fluorocinnamyl chloride and terephthaloyl chloride were mixed in a molar ratio of 0.1:1, and then 0.01 times the mass of terephthaloyl chloride Tween 80 was added to obtain a mixture. The mixture was dissolved in an organic solvent, which was prepared by mixing cyclohexane and chloroform in a 3:2 ratio. The mixture was stirred at 500 r / min for 30 min to obtain the oil phase. Emulsification: At 50℃ and 800r / min, the oil phase was added to the aqueous phase and stirred for 20min to obtain a stable emulsion. The volume ratio of the oil phase to the aqueous phase was 1:3. Encapsulation: 1,6-hexanediamine and diethylenetriamine were mixed in a molar ratio of 1:1 to obtain a mixture. The mixture was then dissolved in twice the mass of deionized water to obtain an aqueous solution of the amine. At room temperature and 600 r / min, the aqueous solution of the amine was added to a stable emulsion and reacted for 15 min. After filtration and washing twice alternately with deionized water and ethanol, the modified phase change microcapsule material was obtained. The molar ratio of 1,6-hexanediamine, diethylenetriamine and terephthaloyl chloride was 1.0:1.0:1. (5) By mass percentage, 30% 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol, 30% pentaerythritol triallyl ether, 3% modified phase change microcapsule material, 5% DVE-3 diluent, 3% 2,4,6-trimethylbenzoyl diphenylphosphine oxide photoinitiator, 0.3% BYK-UV3500 leveling agent and 28.7% solvent are mixed to prepare a UV-curable thermal insulation coating. The solvent is acetone and toluene mixed in a volume ratio of 3:1.

[0025] Example 2 A method for preparing a UV-curable thermal insulation coating includes the following preparation steps: (1) After cleaning and drying PPI40 nickel foam with deionized water, heat-treat it at 700°C for 4 hours in air atmosphere and then cool it naturally to room temperature to obtain nickel foam oxide. (2) Erythritol and mannitol were placed in a drying oven at a mass ratio of 1:1 and dried at 100°C for 9 hours. Then, they were placed in a sealed box and heated to 200°C for 2 hours. After being taken out and naturally cooled to room temperature, they were ground in a planetary ball mill at a speed of 250 r / min for 15 minutes. After passing through a 150-mesh sieve, a pretreated sugar alcohol mixture was obtained. (3) Dissolve the pretreated sugar alcohol mixture in deionized water at 8 times the mass of the pretreated sugar alcohol mixture, add 0.9 times the mass of the pretreated sugar alcohol mixture of oxidized foam metal, and then stir at 90°C and 350r / min until the deionized water is completely evaporated. After drying at 100°C for 1.0h, the modified phase change material is obtained. (4) Aqueous phase: Polyethylene glycol 6000 and deionized water were mixed at a mass ratio of 0.06:1, and modified phase change material with a volume of 0.04 times that of the mixture was added. The mixture was stirred at 550 r / min for 45 min to obtain the aqueous phase. Oil phase: p-Fluorocinnamyl chloride and terephthaloyl chloride were mixed in a molar ratio of 0.2:1, and then 0.02 times the mass of terephthaloyl chloride Tween 80 was added to obtain a mixture. The mixture was dissolved in an organic solvent, which was prepared by mixing cyclohexane and chloroform in a 3:2 ratio. The mixture was stirred at 550 r / min for 45 min to obtain the oil phase. Emulsification: At 50℃ and 900r / min, the oil phase was added to the aqueous phase and stirred for 30min to obtain a stable emulsion. The volume ratio of the oil phase to the aqueous phase was 1:3. Encapsulation: 1,6-hexanediamine and diethylenetriamine were mixed in a molar ratio of 1:1 to obtain a mixture. The mixture was then dissolved in three times its mass of deionized water to obtain an aqueous solution of the amine. At room temperature and 600 r / min, the aqueous solution of the amine was added to a stable emulsion and reacted for 25 min. After filtration and washing three times alternately with deionized water and ethanol, the modified phase change microcapsule material was obtained. The molar ratio of 1,6-hexanediamine, diethylenetriamine, and terephthaloyl chloride was 1.1:1.0:1. (5) By mass percentage, 32% 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol, 32% pentaerythritol triallyl ether, 4% modified phase change microcapsule material, 8% DVE-3 diluent, 3% 2,4,6-trimethylbenzoyl diphenylphosphine oxide photoinitiator, 0.8% BYK-UV3500 leveling agent and 20.2% solvent are mixed to prepare UV-curable thermal insulation coating. The solvent is acetone and toluene mixed in a volume ratio of 3:1.

[0026] Example 3 A method for preparing a UV-curable thermal insulation coating includes the following preparation steps: (1) After cleaning and drying PPI40 nickel foam with deionized water, heat-treat it in air at 800°C for 5 hours and then cool it naturally to room temperature to obtain nickel foam oxide. (2) Erythritol and mannitol were placed in a drying oven at a mass ratio of 1:1 and dried at 105°C for 10 hours. Then, they were placed in a sealed box and heated to 200°C for 2 hours. After being taken out and cooled to room temperature, they were ground in a planetary ball mill at 250 r / min for 15 minutes. After passing through a 150-mesh sieve, a pretreated sugar alcohol mixture was obtained. (3) Dissolve the pretreated sugar alcohol mixture in 10 times the mass of the pretreated sugar alcohol mixture in deionized water, add 1 times the mass of the pretreated sugar alcohol mixture in oxidized foam metal, and then stir at 100℃ and 400r / min until the deionized water is completely evaporated. After drying at 100℃ for 1.5h, the modified phase change material is obtained. (4) Aqueous phase: Polyethylene glycol 6000 and deionized water were mixed at a mass ratio of 0.08:1, and modified phase change material with a volume of 0.05 times that of the mixture was added. The mixture was stirred at 600 r / min for 60 min to obtain the aqueous phase. Oil phase: p-Fluorocinnamyl chloride and terephthaloyl chloride were mixed in a molar ratio of 0.3:1, and then 0.03 times the mass of Tween 80 of terephthaloyl chloride was added to obtain a mixture. The mixture was dissolved in an organic solvent, which was prepared by mixing cyclohexane and chloroform in a 3:2 ratio. The mixture was stirred at 600 r / min for 60 min to obtain the oil phase. Emulsification: At 50℃ and 1000r / min, the oil phase was added to the aqueous phase and stirred for 40min to obtain a stable emulsion. The volume ratio of the oil phase to the aqueous phase was 1:3. Encapsulation: 1,6-hexanediamine and diethylenetriamine were mixed in a molar ratio of 1:1 to obtain a mixture. The mixture was then dissolved in three times its mass of deionized water to obtain an aqueous solution of the amine. At room temperature and 600 r / min, the aqueous solution of the amine was added to a stable emulsion and reacted for 30 min. After filtration and washing three times alternately with deionized water and ethanol, the modified phase change microcapsule material was obtained. The molar ratio of 1,6-hexanediamine, diethylenetriamine, and terephthaloyl chloride was 1.1:1.1:1. (5) By mass percentage, 30% 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol, 30% pentaerythritol triallyl ether, 5% modified phase change microcapsule material, 10% DVE-3 diluent, 5% 2,4,6-trimethylbenzoyl diphenylphosphine oxide photoinitiator, 1% BYK-UV3500 leveling agent and 19% solvent are mixed to prepare a UV-curable thermal insulation coating. The solvent is acetone and toluene mixed in a volume ratio of 3:1.

[0027] Comparative Example 1 The difference between Comparative Example 1 and Example 2 is that step (4) is different, and 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol in step (5) is replaced with 1,2-ethanedithiol; the rest of the steps are the same as in Example 2.

[0028] Comparative Example 2 The difference between Comparative Example 2 and Example 2 lies in step (2), where pentaerythritol triallyl ether in step (5) is replaced with diallyl ether; the remaining steps are the same as in Example 2.

[0029] Comparative Example 3 The difference between Comparative Example 3 and Example 2 is that step (1) is omitted, and the oxidized foam metal in step (3) is replaced with foam metal; the remaining steps are the same as in Example 2.

[0030] Comparative Example 4 The difference between Comparative Example 4 and Example 2 is that steps (1) and (3) are omitted, and the modified phase change material in step (4) is replaced with a pretreated sugar alcohol mixture; the remaining steps are the same as in Example 2.

[0031] Comparative Example 5 The difference between Comparative Example 5 and Example 2 is that step (4) is different, and the p-fluorocinnamoyl chloride in step (4) is deleted; the rest of the steps are the same as in Example 2.

[0032] Comparative Example 6 The difference between Comparative Example 6 and Example 2 is that step (4) is omitted, and the modified phase change microcapsule material in step (5) is replaced with a modified phase change material; the remaining steps are the same as in Example 2.

[0033] Example of effect Table 1 below shows the performance analysis results of the UV-cured thermal insulation coatings of Examples 1 to 3 and Comparative Examples 1 to 6 of the present invention.

[0034] Table 1 A comparison of the experimental data from Example 2 with Comparative Examples 1-2 reveals that the present invention uses 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol and pentaerythritol triallyl ether as raw materials to prepare a UV-curable coating. Ethyl-2-(mercaptomethyl)-1,3-propanedithiol and pentaerythritol triallyl ether undergo a thiol-ene click reaction under ultraviolet light, resulting in rapid curing and the formation of a solid coating film within a short time. This improves production efficiency, reduces the evaporation time of the coating during curing, and minimizes environmental impact. Furthermore, the thermal insulation agent provides double bonds on the surface of the fluorocinnamoyl chloride-modified phase change microcapsule material, which also provide active sites during ultraviolet curing, allowing for the formation of a solid coating film through the thiol-ene reaction. The click reaction directly bonds with the resin network, forming a covalent "microcapsule-matrix" connection, enhancing interfacial strength and further improving the mechanical properties of the cured coating. Furthermore, 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol contains multiple thiol groups, enabling the formation of a highly cross-linked polymer network structure. This dense polymer network effectively prevents external corrosive substances, such as moisture, oxygen, acids, and alkalis, from penetrating into the coating, thus protecting the substrate from corrosion. The pentaerythritol backbone provides rigidity, while the ethyl branches and thioether bonds impart toughness, preventing brittle cracking. A comparison of the experimental data from Example 2 and Comparative Examples 3-4 reveals that this invention utilizes oxide foam metal... The modified phase change material (PCM) has oxide active sites on its surface, which can form hydrogen bonds with sugar alcohol compounds, thus more firmly supporting the sugar alcohol compounds. Furthermore, the foam metal possesses good thermal conductivity, which effectively improves the low thermal conductivity of sugar alcohol mixtures after loading, enhancing the thermal conductivity and heat transfer efficiency during the phase change process. When the ambient temperature changes, the modified PCM can absorb or release heat more quickly, achieving a more efficient phase change and improving the insulation effect. A comparison of the experimental data from Example 2 and Comparative Example 5 reveals that the present invention, using fluorinated cinnamoyl chloride-modified polyamide as the shell material for phase change microcapsules, introduces fluorine atoms into the polyamide shell material. The strong hydrophobicity of the polyamide resin can significantly reduce the water absorption rate of the shell material, reduce the erosion of the phase change material by water penetration, prevent the microcapsules from rupturing due to moisture absorption and expansion, improve the coating effect of the polyamide shell material, and extend the service life of the microcapsule material. In addition, the fluorine group can reduce the surface energy of the shell material, reduce the adhesion between microcapsules, and improve its dispersibility in UV-curable coatings. A comparison of the experimental data of Example 2 and Comparative Example 6 shows that the present invention uses polyamide resin to encapsulate the modified phase change material. The encapsulation of polyamide resin can effectively prevent the phase change material from direct contact with the environment, playing a protective role. At the same time, it can also prevent the leakage of the phase change material during use, further improving the thermal insulation performance of the coating.

[0035] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a UV-curable thermal insulation coating, characterized in that, The preparation steps include the following: (1) After cleaning and drying PPI40 nickel foam with deionized water, heat-treat it at 700°C for 4 hours in air atmosphere and then cool it naturally to room temperature to obtain nickel foam oxide. (2) Erythritol and mannitol were placed in a drying oven at a mass ratio of 1:1 and dried at 100°C for 9 hours. Then, they were placed in a sealed box and heated to 200°C for 2 hours. After being taken out and naturally cooled to room temperature, they were ground in a planetary ball mill at a speed of 250 r / min for 15 minutes. After passing through a 150-mesh sieve, a pretreated sugar alcohol mixture was obtained. (3) Dissolve the pretreated sugar alcohol mixture in deionized water at 8 times the mass of the pretreated sugar alcohol mixture, add 0.9 times the mass of the pretreated sugar alcohol mixture of oxidized foam metal, and then stir at 90°C and 350r / min until the deionized water is completely evaporated. After drying at 100°C for 1.0h, the modified phase change material is obtained. (4) Aqueous phase: Polyethylene glycol 6000 and deionized water were mixed at a mass ratio of 0.06:1, and modified phase change material with a volume of 0.04 times that of the mixture was added. The mixture was stirred at 550 r / min for 45 min to obtain the aqueous phase. Oil phase: p-Fluorocinnamyl chloride and terephthaloyl chloride were mixed in a molar ratio of 0.2:1, and then 0.02 times the mass of terephthaloyl chloride Tween 80 was added to obtain a mixture. The mixture was dissolved in an organic solvent, which was prepared by mixing cyclohexane and chloroform in a 3:2 ratio. The mixture was stirred at 550 r / min for 45 min to obtain the oil phase. Emulsification: At 50℃ and 900r / min, the oil phase was added to the aqueous phase and stirred for 30min to obtain a stable emulsion. The volume ratio of the oil phase to the aqueous phase was 1:

3. Encapsulation: 1,6-hexanediamine and diethylenetriamine were mixed in a molar ratio of 1:1 to obtain a mixture. The mixture was then dissolved in three times its mass of deionized water to obtain an aqueous solution of the amine. At room temperature and 600 r / min, the aqueous solution of the amine was added to a stable emulsion and reacted for 25 min. After filtration and washing three times alternately with deionized water and ethanol, the modified phase change microcapsule material was obtained. The molar ratio of 1,6-hexanediamine, diethylenetriamine, and terephthaloyl chloride was 1.1:1.0:

1. (5) By mass percentage, 32% 2-ethyl-2-(mercaptomethyl)-1,3-propanedithiol, 32% pentaerythritol triallyl ether, 4% modified phase change microcapsule material, 8% DVE-3 diluent, 3% 2,4,6-trimethylbenzoyl diphenylphosphine oxide photoinitiator, 0.8% BYK-UV3500 leveling agent and 20.2% solvent are mixed to prepare UV-curable thermal insulation coating. The solvent is acetone and toluene mixed in a volume ratio of 3:1.

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