A heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating

Abstract

The invention discloses a heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating, which belongs to the technical field of powder coatings. The fluorocarbon powder coating is prepared by melt-blending FEVE fluorocarbon resin, super-weather-resistant polyester resin, isocyanate, hydroxyalkylamide, leveling agent, cobalt turquoise pigment, titanium dioxide and additives in a mass ratio of 60:35:5:10:2:15:5:5-15. FEVE fluorocarbon resin gives the coating excellent weather resistance, aging resistance and corrosion resistance, and can be cross-linked with isocyanate to play a protective role; super-weather-resistant polyester resin enhances the weather resistance of fluorocarbon powder coating and reduces the cost; cobalt turquoise pigment gives fluorocarbon powder coating a turquoise green color; titanium dioxide has infrared reflection ability to ensure heat insulation, and the additives are extremely compatible with fluorocarbon powder coatings, which can give full play to the performance and significantly improve the antibacterial property, weather resistance and a certain degree of corrosion resistance and heat resistance of fluorocarbon powder coatings.

Description

Technical Field

[0001] The invention belongs to the technical field of powder coatings, and in particular relates to a heat-insulating, bacteria-proof and weather-resistant turquoise green fluorocarbon powder coating. Background Art

[0002] Powder coating is a solid powdered synthetic resin coating composed of solid resin, pigment, filler and additives. It has developed rapidly in recent years due to its harmlessness, high efficiency, resource saving and environmental protection. However, the service life of brightly colored powder coating is difficult to exceed 15 years. Usually, the surface will crack and lose its original color after about 10 years of use, which not only affects the appearance of the building, but also poses certain safety hazards. In addition, traditional powder coatings have insufficient UV resistance. After long-term exposure outdoors, they absorb a large amount of solar heat, causing the indoor temperature to rise.

[0003] The emergence of fluorocarbon powder coatings has solved this problem very well. Fluorocarbon powder coatings refer to coatings with fluororesins as the main film-forming material. Because its structure contains more fluorocarbon bonds, its performance is not only excellent in light and weather resistance, but also has high surface hardness and excellent corrosion resistance compared with traditional powder coatings. It is light in weight during use and will not increase the load on the surface of the object being used. It also has good adhesion to metals, and surface dust can be automatically cleaned by rain. However, fluorocarbon powder coatings have poor reflection of infrared light, which affects their thermal insulation. In addition, the antibacterial and flame retardant properties of fluorocarbon powder coatings need to be improved to meet their higher demands in the field of powder coatings. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a heat-insulating, bacteria-proof and weather-resistant fluorocarbon turquoise powder.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating is prepared by the following steps:

[0007] FEVE fluorocarbon resin, super weather-resistant polyester resin, isocyanate, hydroxyalkylamide (curing agent), leveling agent, cobalt turquoise pigment (pigment filler), titanium dioxide and additives are stirred and mixed evenly, added into a twin-screw extruder, melt-blended, extruded, tableted, cooled, crushed by a grinder, sieved and packaged to obtain a heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating.

[0008] No organic solvent is added during the preparation process, which is environmentally friendly and harmless. FEVE fluorocarbon resin is selected as the main body because it contains FC bonds with super strong bond energy and can react with isocyanate to form a highly cross-linked polymer coating, which gives the coating excellent weather resistance, aging resistance and corrosion resistance, and also ensures the protective performance of the fluorocarbon coating on the substrate; super weather-resistant polyester resin can not only further enhance the weather resistance of fluorocarbon powder coatings, but also reduce costs; hydroxyalkylamide has low toxicity, good storage stability and can allow the coating to cure at low temperatures; cobalt turquoise pigment gives fluorocarbon powder coatings a turquoise green color; titanium dioxide has a high refractive index and high whiteness, can produce high refraction and reflection effects on sunlight, and has good weather resistance, which can give fluorocarbon powder coatings excellent infrared reflection ability and a certain weather resistance, ensuring the thermal insulation of fluorocarbon powder coatings;

[0009] Furthermore, the mass ratio of FEVE fluorocarbon resin, super weather-resistant polyester resin, isocyanate, hydroxyalkylamide, leveling agent, cobalt turquoise pigment, titanium dioxide, and additives is 60:35:5:10:2:15:5:5-15.

[0010] Furthermore, the isocyanate is triglycidyl isocyanurate or biuret polyisocyanate.

[0011] Furthermore, the leveling agent is a polyacrylate solution or an acrylate copolymer solution.

[0012] Furthermore, the auxiliary agent is prepared by the following steps:

[0013] S1. Add 1,3-acetone dicarboxylic acid, DAST (diethylaminosulfur trifluoride, fluorination reagent) and dichloromethane into a beaker, stir and mix evenly at room temperature, react for 40 minutes, filter, take the filter cake, wash it with anhydrous ethanol for 3 times, and dry it to obtain intermediate 1; the ratio of 1,3-acetone dicarboxylic acid, DAST and dichloromethane is 14.6 g:8.5 g:50 mL;

[0014] Under the action of the fluorination reagent, the carbonyl group on 1,3-acetone dicarboxylic acid is converted into a difluorinated compound. The fluorination reagent is selective and the carboxyl group is not affected, thereby obtaining intermediate 1. The specific reaction process is as follows:

[0015]

[0016] S2, in a three-necked flask equipped with a stirring device, the intermediate 1, 3-butene-1-ol and ethyl acetate were mixed, and concentrated sulfuric acid solution (catalyst, dehydrating agent) was slowly added to the solution while stirring, and the reaction was carried out at 75 ° C for 6 hours. After the reaction was completed, most of the solvent was first removed by rotary evaporation, and then purified by column chromatography (eluent using a mixed solvent of methanol / chloroform, the volume ratio of the two was 3:2), and the eluent was removed by rotary evaporation to obtain intermediate 2; the ratio of the amount of intermediate 1, 3-butene-1-ol, ethyl acetate, and concentrated sulfuric acid solution was 18.7g:7.2g:50mL:20mL;

[0017] Under the catalysis of concentrated sulfuric acid, the carboxyl group on intermediate 1 and the hydroxyl group on 3-butene-1-ol undergo esterification reaction. By controlling the molar ratio of the two to be close to 1:1 and the intermediate 1 to be slightly excessive, only one carboxyl group on intermediate 1 participates in the reaction to obtain intermediate 2. The specific reaction process is as follows:

[0018]

[0019] S3, add 2,6-diaminopyridine, intermediate 2, DCC (dicyclohexylcarbodiimide, dehydrating agent) and pyridine to a three-necked flask equipped with a stirring device, mix, stir evenly, and react for 75 minutes in a 65°C water bath. After the reaction, first remove part of the solvent by rotary evaporation, and then purify by column chromatography (the eluent is a mixed solvent of cyclohexane / ethyl acetate, and the volume ratio of the two is 3:5), and finally remove the eluent by rotary evaporation to obtain intermediate 3; the ratio of the amount of 2,6-diaminopyridine, intermediate 2, DCC, and pyridine is 10.9g:50.2g:41.2g:200mL;

[0020] The amino group of 2,6-diaminopyridine and the carboxyl group of intermediate 2 undergo an amidation reaction. With the help of a dehydrating agent, the reaction can be carried out under relatively mild conditions. By controlling the molar ratio of the two to be close to 1:2 and a slight excess of intermediate 2, two amino groups on 2,6-diaminopyridine participate in the reaction to obtain intermediate 3. The specific reaction process is shown below:

[0021]

[0022] S4, add intermediate 3 and pyridine to a three-necked flask equipped with a stirring device, mix, stir evenly, add sodium hypochlorite solution dropwise, react at 85°C for 3h, after the reaction is completed, first remove part of the solvent by rotary evaporation, and then purify by column chromatography (the eluent is a mixed solvent of cyclohexane / ethyl acetate, the volume ratio of the two is 2:5), and finally remove the eluent by rotary evaporation to obtain an auxiliary agent; the ratio of the amount of intermediate 3, pyridine, and sodium hypochlorite solution is 51.7g:100mL:80mL;

[0023] The intermediate 4 undergoes a chlorination reaction with a sodium hypochlorite solution to obtain an auxiliary agent; the structural formula of the auxiliary agent is shown below:

[0024]

[0025] The prepared auxiliary agent is mainly composed of pyridine, and is connected with FC bond, halamine and ester structure through amide group, and contains carbon-carbon double bond at the end, wherein the carbon-carbon double bond can be grafted onto the molecular chain of fluorocarbon resin during melting to produce chemical bonding, which can not only improve the compatibility of the auxiliary agent and fluorocarbon resin, but also improve the mutual force between the two, improve the mechanical properties, and also improve the resistance of the auxiliary agent to migration and exudation, so as to obtain the durability of the performance; in addition, the introduction of FC bond, the FC bond has small polarity and high bond energy, and the better the stability, can also enhance the heat resistance of fluorocarbon resin, and can increase the compatibility with fluorocarbon resin, so as to give full play to the performance, not only that, the FC bond can well coat the CC main chain, shield it, play a protective role, and further improve the stability of fluorocarbon resin; in addition, halamine, as an excellent antibacterial structure, has certain regeneration, and can release strong oxidizing Cl + Destroy the bacterial structure; finally, the ester group can ensure compatibility with the super weather-resistant polyester resin, so that the performance of the prepared additive can be fully exerted.

[0026] Beneficial effects of the present invention:

[0027] The fluorocarbon powder coating of the present invention is prepared by melt blending FEVE fluorocarbon resin, super weather-resistant polyester resin, isocyanate, hydroxyalkylamide, leveling agent, cobalt turquoise pigment, titanium dioxide, dimethyl silicone oil and additives, without adding organic solvents, and is harmless to the environment. The FEVE fluorocarbon resin as the main body not only gives the coating excellent weather resistance, aging resistance and corrosion resistance, but also can be highly cross-linked with isocyanate to provide protection for the substrate; the super weather-resistant polyester resin enhances the weather resistance of the fluorocarbon powder coating and reduces the cost; the hydroxyalkylamide enables the coating to be cured at low temperature; the cobalt turquoise pigment gives the fluorocarbon powder coating a turquoise green color; the titanium dioxide can give the fluorocarbon powder coating excellent infrared reflection ability and certain weather resistance, thereby ensuring the heat insulation of the fluorocarbon powder coating; the additives are extremely compatible with the fluorocarbon powder coating, can give full play to the performance, and significantly improve the antibacterial property, weather resistance and a certain degree of mechanical property and heat resistance of the fluorocarbon powder coating. The fluorocarbon powder coating thus prepared has stable and efficient weather resistance, antibacterial properties, heat insulation, a certain degree of corrosion resistance and heat resistance, is environmentally friendly and harmless, and is not easy to change color. It has important application significance in the field of powder coatings. DETAILED DESCRIPTION

[0028] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] Preparation aids

[0031] S1. Add 14.6 g of 1,3-acetone dicarboxylic acid, 8.5 g of DAST and 50 mL of dichloromethane into a beaker, stir and mix evenly at room temperature, react for 40 min, filter, take the filter cake, wash it with anhydrous ethanol for 3 times, and dry it to obtain intermediate 1;

[0032] S2, in a three-necked flask equipped with a stirring device, 18.7g of intermediate 1, 7.2g of 3-butene-1-ol and 50mL of ethyl acetate were mixed, and 20mL of concentrated sulfuric acid solution (mass fraction 98%) was slowly added to the solution while stirring, and the mixture was reacted at 75°C for 6h. After the reaction was completed, most of the solvent was first removed by rotary evaporation, and then purified by column chromatography (the eluent was a mixed solvent of methanol / chloroform, and the volume ratio of the two was 3:2), and the eluent was removed by rotary evaporation to obtain intermediate 2;

[0033] S3, in a three-necked flask equipped with a stirring device, add 10.9 g of 2,6-diaminopyridine, 50.2 g of intermediate 2, 41.2 g of DCC and 200 mL of pyridine, mix and stir evenly, place in a 65°C water bath, react for 75 min, after the reaction is completed, first remove part of the solvent by rotary evaporation, then purify by column chromatography (the eluent is a mixed solvent of cyclohexane / ethyl acetate, the volume ratio of the two is 3:5), finally remove the eluent by rotary evaporation to obtain intermediate 3;

[0034] S4. Add 51.7 g of intermediate 3 and 100 mL of pyridine into a three-necked flask equipped with a stirring device, mix and stir evenly, add 80 mL of sodium hypochlorite solution (mass fraction 12%) dropwise, react at 85°C for 3 h. After the reaction is completed, first remove part of the solvent by rotary evaporation, and then purify by column chromatography (the eluent is a mixed solvent of cyclohexane / ethyl acetate, the volume ratio of the two is 2:5), and finally remove the eluent by rotary evaporation to obtain an auxiliary agent.

[0035] Example 2

[0036] Preparation aids

[0037] S1. Add 29.2 g of 1,3-acetone dicarboxylic acid, 17.0 g of DAST and 100 mL of dichloromethane into a beaker, stir and mix evenly at room temperature, react for 40 min, filter, take the filter cake, wash it with anhydrous ethanol for 3 times, and dry it to obtain intermediate 1.

[0038] S2. In a three-necked flask equipped with a stirring device, 37.4 g of intermediate 1, 14.4 g of 3-butene-1-ol and 100 mL of ethyl acetate were mixed, and 40 mL of concentrated sulfuric acid solution (mass fraction 98%) was slowly added to the solution while stirring. The mixture was reacted at 75° C. for 6 h. After the reaction was completed, most of the solvent was first removed by rotary evaporation, and then purified by column chromatography (the eluent was a mixed solvent of methanol / chloroform, and the volume ratio of the two was 3:2), and the eluent was removed by rotary evaporation to obtain intermediate 2;

[0039] S3, in a three-necked flask equipped with a stirring device, add 21.8 g of 2,6-diaminopyridine, 100.4 g of intermediate 2, 82.4 g of DCC and 400 mL of pyridine, mix and stir evenly, place in a 65°C water bath, react for 75 min, after the reaction is completed, first remove part of the solvent by rotary evaporation, then purify by column chromatography (the eluent is a mixed solvent of cyclohexane / ethyl acetate, the volume ratio of the two is 3:5), and finally remove the eluent by rotary evaporation to obtain intermediate 3;

[0040] S4. Add 103.4 g of intermediate 3 and 200 mL of pyridine into a three-necked flask equipped with a stirring device, mix and stir evenly, add dropwise 160 mL of sodium hypochlorite solution (mass fraction 12%), react at 85°C for 3 h. After the reaction is completed, first remove part of the solvent by rotary evaporation, and then purify by column chromatography (the eluent is a mixed solvent of cyclohexane / ethyl acetate, the volume ratio of the two is 2:5), and finally remove the eluent by rotary evaporation to obtain an auxiliary agent.

[0041] Example 3

[0042] 60g of FEVE fluorocarbon resin, 35g of super weather-resistant polyester resin (CRYLCOAT 4540-0), 5g of biuret polyisocyanate, 10g of hydroxyalkylamide, 2g of polyacrylate solution, 15g of cobalt turquoise pigment, 5g of titanium dioxide and 5g of the additive prepared in Example 1 are stirred and mixed evenly, added into a twin-screw extruder, melt blended, extruded, tableted, cooled, crushed by a grinder, sieved and packaged to obtain a heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating.

[0043] Example 4

[0044] 60g of FEVE fluorocarbon resin, 35g of super weather-resistant polyester resin (CRYLCOAT 4540-0), 5g of triglycidyl isocyanurate, 10g of hydroxyalkylamide, 2g of acrylate copolymer solution, 15g of cobalt turquoise pigment, 5g of titanium dioxide and 10g of the additive prepared in Example 1 are stirred and mixed evenly, added into a twin-screw extruder, melt blended, extruded, tableted, cooled, crushed by a grinder, sieved and packaged to obtain a heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating.

[0045] Example 5

[0046] 60g of FEVE fluorocarbon resin, 35g of super weather-resistant polyester resin (CRYLCOAT 4540-0), 5g of biuret polyisocyanate, 10g of hydroxyalkylamide, 2g of polyacrylate solution, 15g of cobalt turquoise pigment, 5g of titanium dioxide and 15g of the additive prepared in Example 2 are stirred and mixed evenly, added into a twin-screw extruder, melt-blended, extruded, tableted, cooled, crushed by a grinder, sieved and packaged to obtain a heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating.

[0047] Comparative Example 1

[0048] The auxiliary agent in Example 5 was replaced by chloramine T 127-65-1 antibacterial agent of equal quality produced by Hubei Kewode Chemical Co., Ltd., and the remaining steps were the same as in Example 5.

[0049] Comparative Example 2

[0050] No additives are added.

[0051] Comparative Example 3

[0052] Use ordinary powder coating made of FEVE fluorocarbon resin.

[0053] The fluorocarbon powder coatings prepared in Examples 3-5 and Comparative Examples 1-3 were made into corresponding shapes according to different test standards and subjected to the following performance tests:

[0054] The national standard GB / T 21866-2008 "Determination of antibacterial properties and antibacterial effects of antibacterial coatings (paint films)" was used to determine the inhibition rates of Escherichia coli and Staphylococcus aureus before and after the samples were placed at 200℃ for 12 hours.

[0055] The national standard GB / T 1763-79 "Determination of chemical resistance of paint film" is used to determine the acid and alkali resistance of the coating film;

[0056] ISO 4892-1 was used to test the changes in the paint surface after xenon lamp aging;

[0057] The sample was applied to a cubic aluminum box with a side length of 10 cm, and the initial box temperature was recorded as T1. The boxes were placed outdoors and fully exposed to sunlight for 6 hours, and the box temperature was recorded as T2. The temperature change before and after was calculated as T3, T3 = T2-T1;

[0058] The antibacterial results are shown in Table 1:

[0059] Table 1

[0060]

[0061]

[0062] Some of the measured results are shown in Table 2:

[0063] Table 2

[0064]

[0065] It can be seen from the above two tables that the prepared fluorocarbon powder coating has stable and efficient weather resistance, antibacterial property, heat insulation and a certain degree of corrosion resistance and heat resistance and is environmentally friendly and harmless, and is not easy to change color, which has important application significance in the field of powder coatings.

[0066] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0067] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating, characterized in that: FEVE fluorocarbon resin, super weather-resistant polyester resin with the brand name of CRYLCOAT 4540-0, isocyanate, hydroxyalkylamide, leveling agent, cobalt turquoise pigment, titanium dioxide and additives are stirred and mixed, added into a twin-screw extruder, melt-blended, extruded, tableted, cooled, and crushed in a grinder to obtain a heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating; Wherein, the auxiliary agent is prepared by the following steps: S1, 1,3-acetone dicarboxylic acid, DAST and dichloromethane were stirred and mixed at room temperature, reacted for 40 minutes, filtered, the filter cake was taken, washed with anhydrous ethanol, and dried to obtain intermediate 1; S2, mixing the intermediate 1, 3-butene-1-ol and ethyl acetate, slowly adding concentrated sulfuric acid solution, reacting at 75°C for 6 hours, rotary evaporation, column chromatography purification, and rotary evaporation again to obtain intermediate 2; S3, 2,6-diaminopyridine, intermediate 2, DCC and pyridine were mixed, stirred evenly, reacted in a 65°C water bath for 75 min, rotary evaporated, purified by column chromatography, and rotary evaporated again to obtain intermediate 3; S4, mixing the intermediate 3 and pyridine, stirring evenly, adding sodium hypochlorite solution dropwise, reacting at 85°C for 3h, rotary evaporation, column chromatography purification, and rotary evaporation again to obtain an auxiliary agent; Among them, the ratio of the amount of intermediate 1, 3-butene-1-ol, ethyl acetate, and concentrated sulfuric acid solution in step S2 is 18.7 g:7.2 g:50 mL:20 mL; the ratio of the amount of 2,6-diaminopyridine, intermediate 2, DCC, and pyridine in step S3 is 10.9 g:50.2 g:41.2 g:200 mL.

2. The heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating according to claim 1, characterized in that: In step S1, the ratio of 1,3-acetone dicarboxylic acid, DAST, and dichloromethane is 14.6 g:8.5 g:50 mL.

3. The heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating according to claim 1, characterized in that: In step S4, the ratio of the amount of intermediate 3, pyridine and sodium hypochlorite solution is 51.7 g: 100 mL: 80 mL.

4. The heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating according to claim 1, characterized in that: The mass ratio of FEVE fluorocarbon resin, super weather-resistant polyester resin, isocyanate, hydroxyalkylamide, leveling agent, cobalt turquoise pigment, titanium dioxide and additives is 60:35:5:10:2:15:5:5-15.

5. The heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating according to claim 1, characterized in that: The leveling agent is a polyacrylate solution or an acrylate copolymer solution.

6. The heat-insulating, antibacterial and weather-resistant turquoise green fluorocarbon powder coating according to claim 1, characterized in that: The isocyanate is triglycidyl isocyanurate or biuret polyisocyanate.

Images