Wear-resistant flame-retardant transfer coating, and preparation method and application thereof

Abstract

The present application relates to the technical field of paint, and more particularly to a wear-resistant and flame-retardant transfer paint, a preparation method and application thereof.The transfer paint comprises the following raw materials in parts by weight: 10-25 parts of modified polyacrylic acid resin, 5-10 parts of cellulose resin, 45-60 parts of solvent, 3-7 parts of flame-retardant carbon nanotubes, 0.05-0.2 parts of defoaming agent, 0.1-0.25 parts of leveling agent, and 0.05-0.1 parts of wetting agent.The transfer paint has excellent flame-retardant performance, wear-resistant performance, bacteriostatic performance and adhesion.

Description

Technical Field

[0001] This invention relates to the field of coating technology, and in particular to a wear-resistant and flame-retardant transfer coating, its preparation method, and its application. Background Technology

[0002] Transfer coatings, with their excellent transfer performance and surface decoration effects, are widely used in the surface decoration and functional treatment of industries such as leather, wallpaper, hot stamping cloth, tablecloths, electroplated aluminum, and cigarette packaging. In actual production processes, the transfer coating is first evenly applied to a release substrate (such as PET film) through a coating process to form a coating layer; then, through processes such as aluminizing and lamination, the coating, along with the metal or pattern layer it carries, is finally transferred completely to the surface of the target substrate, thereby achieving effects such as high gloss, metallic texture, or anti-counterfeiting.

[0003] Currently, the main components of commercially available transfer coatings are acrylic resin and cellulose resin, combined with a suitable amount of solvent system. This type of system can provide basic mechanical strength, film-forming properties, and initial adhesion to the aluminized layer. However, under long-term use or high-frequency friction environments, traditional transfer coatings are prone to scratches, wear, and even localized peeling. Once the surface coating is damaged, not only is the appearance severely damaged, but the internal aluminized layer will also oxidize and corrode due to the loss of protection, leading to a rapid decline in overall protective function and significantly shortening the product's lifespan and commercial value.

[0004] Furthermore, with the increasing demand for flame-retardant materials in complex applications, transfer coatings themselves also need to possess reliable flame-retardant properties. Especially in applications such as interior decoration and packaging materials, if the coating is flammable, it will spread rapidly upon contact with a source of ignition, significantly increasing the risk of fire. However, most existing products only focus on conventional properties such as gloss and adhesion, generally lacking efficient flame-retardant designs, making it difficult to simultaneously meet the dual engineering requirements of high abrasion resistance and high flame retardancy. Therefore, there is an urgent need to improve the abrasion resistance and flame retardancy of transfer coatings to meet the safety and durability requirements of practical applications. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, one of the objectives of this invention is to provide a wear-resistant and flame-retardant transfer coating that has excellent flame-retardant properties, wear resistance, antibacterial properties and adhesion.

[0006] The second objective of this invention is to provide a method for preparing a wear-resistant and flame-retardant transfer coating that is easy to operate.

[0007] The third objective of this invention is to provide an application of a wear-resistant and flame-retardant transfer coating, which has broad prospects.

[0008] One of the objectives of this invention is achieved through the following technical solution: A wear-resistant and flame-retardant transfer coating, by weight, comprises the following raw materials: 10-25 parts modified polyacrylic acid resin, 5-10 parts cellulose resin, 45-60 parts solvent, 3-7 parts flame-retardant carbon nanotubes, 0.05-0.2 parts defoamer, 0.1-0.25 parts leveling agent, and 0.05-0.1 parts wetting agent; The preparation process of the flame-retardant carbon nanotubes is as follows: (1) Hydroxylated carbon nanotubes were added to N,N-dimethylformamide, and then a catalyst and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid were added. After the reaction, the mixture was purified to obtain amination carbon nanotubes. (2) The amination carbon nanotubes were added to propanol, and then 2-bromoethylphosphonic acid diethyl ester was added. After the reaction, the mixture was purified to obtain the flame-retardant carbon nanotubes.

[0009] The above reaction process is as follows: This invention first uses p-toluenesulfonic acid as a catalyst to esterify hydroxylated carbon nanotubes with 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid, introducing tertiary amine groups on the surface of the carbon nanotubes to obtain amination carbon nanotubes; then, the amination carbon nanotubes are subjected to quaternization reaction with diethyl 2-bromoethylphosphonate, simultaneously grafting phosphate ester structures and quaternary ammonium salt groups onto the surface of the carbon nanotubes, finally obtaining flame-retardant carbon nanotubes.

[0010] Preferably, the catalyst in step (1) is p-toluenesulfonic acid; the mass ratio of the hydroxylated carbon nanotubes, the catalyst, and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid is 1:(0.9-1.2):(0.06-0.1); the reaction temperature is 105-110℃ and the time is 3-5h.

[0011] Preferably, in step (2), the mass ratio of the amination carbon nanotubes to diethyl 2-bromoethylphosphonate is 1:(2.7-3.5); the reaction temperature is 60-70℃ and the reaction time is 12-16h.

[0012] Preferably, the preparation process of the modified polyacrylic acid resin is as follows: S1. Mix ethyl methacrylate, butyl methacrylate, isobornyl acrylate, functional monomer and ethyl acetate to obtain mixed solution 1; take 1 / 4 to 1 / 3 of the mixed solution 1, heat it to obtain mixed solution 2; S2. Mix the remaining mixed solution 1 with 2 / 3-3 / 4 of the initiator to obtain mixed solution 3; add mixed solution 3 to mixed solution 2, keep it at a warm temperature for reaction, then add the remaining initiator for heating reaction, cool, adjust the solid content, and discharge to obtain the final product; The structure of the functional unit mentioned in step S1 is as follows: .

[0013] Preferably, in step S1, the mass ratio of ethyl methacrylate, butyl methacrylate, isobornyl acrylate, functional monomer, and ethyl acetate is (20-25):(10-15):(1-5):(0.5-2.5):(50-60); the heating temperature is 70-80℃; in step S2, the initiator is azobisisobutyronitrile or benzoyl peroxide; based on the total amount of ethyl methacrylate used, the mass ratio of the initiator to ethyl methacrylate is 1:(20-25); the heat preservation reaction time is 1-2 hours; the heating reaction temperature is 80-90℃, and the time is 2.5-5 hours; the solid content is adjusted to 45-50%.

[0014] Preferably, the preparation method of the functional monomer is as follows: (a) Cystamine dihydrochloride was added to anhydrous ethanol, followed by the addition of 1-formaldehyde piperazine and glacial acetic acid. The mixture was refluxed and purified to obtain intermediate 1. The structural formula of intermediate 1 is: (b) The intermediate 1, vinyl chloroacetate, and sodium bicarbonate were added to tetrahydrofuran, and the mixture was purified after reaction to obtain the functional monomer.

[0015] This invention prepares intermediate 1 containing both disulfide bonds and Schiff base groups by reacting cystamine dihydrochloride and 1-formaldehyde piperazine with a Schiff base. Intermediate 1 is then subjected to a nucleophilic substitution reaction with vinyl chloroacetate to introduce terminal alkenyl groups into the molecule, thereby obtaining a functional monomer.

[0016] Preferably, in step (a), the molar ratio of cystamine dihydrochloride, 1-formaldehyde piperazine, and glacial acetic acid is 1:(2-2.2):(0.3-0.5); the reflux reaction time is 8-10 h; in step (b), the molar ratio of intermediate 1, vinyl chloroacetate, and sodium bicarbonate is 1:(2.5-2.7):(2.7-3); the reaction time is 20-24 h.

[0017] Preferably, the cellulose resin is selected from cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate; the defoamer is selected from BYK-066N, BYK-051, and BYK-052; the wetting agent is polyoxyethylene alkyl ether; the leveling agent is selected from BYK-306, BYK-333, and BYK-323; and the solvent is selected from ethyl acetate, n-butyl acetate, n-propyl acetate, ethanol, isopropanol, butanone, propylene glycol monomethyl ether, and propylene glycol ethyl ether.

[0018] The second objective of this invention is achieved by the following technical solution: The preparation method of the above-mentioned wear-resistant and flame-retardant transfer coating includes the following steps: Mix all ingredients thoroughly to obtain the final product.

[0019] The third objective of this invention is achieved by the following technical solution: The aforementioned wear-resistant and flame-retardant transfer coatings are applied in the packaging industry.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a wear-resistant and flame-retardant transfer coating, comprising modified polyacrylic acid resin, cellulose resin, solvent, defoamer, leveling agent, wetting agent, and flame-retardant carbon nanotubes. Through the synergistic effect of its components, this coating maintains good processing performance while also exhibiting excellent flame retardant properties, wear resistance, antibacterial properties, and adhesion.

[0021] 2. This invention enhances the flame-retardant and antibacterial properties of coatings by adding flame-retardant carbon nanotubes. The surface of these flame-retardant carbon nanotubes is grafted with phosphate ester structures and quaternary ammonium salt groups via a quaternization reaction, which synergistically construct a nitrogen-phosphorus intumescent flame-retardant system. During combustion, this system forms a dense char layer, effectively blocking heat and oxygen transfer, thereby endowing the coating with excellent flame-retardant properties and reducing the risk of fire. Simultaneously, the quaternary ammonium salt groups grafted onto the surface of the flame-retardant carbon nanotubes possess bactericidal activity, disrupting the cell membrane structure of microorganisms and inhibiting their metabolism and reproduction, thus giving the coating excellent antibacterial properties.

[0022] 3. This invention effectively improves the wear resistance and adhesion of coatings by introducing functional monomers into the polyacrylate system via free radical copolymerization. The functional monomers contain disulfide bonds, Schiff base groups, and piperazine ring structures. The disulfide bonds and Schiff base groups endow the coating with self-healing capabilities; the piperazine ring, as a rigid structural unit, enhances the rigidity of the polymer molecular chain, improves the coating's resistance to deformation and surface hardness, thereby effectively improving the coating's wear resistance. Furthermore, the polar groups (piperazine ring, Schiff base groups, etc.) in the functional monomer molecules can coordinate with aluminum atoms, optimizing the interfacial compatibility between the coating and the aluminum plating layer, improving adhesion, and avoiding the problem of aluminum stripping during the peeling process. Attached Figure Description

[0023] Figure 1 SEM image of the flame-retardant carbon nanotubes obtained in Example 8 of this invention. Detailed Implementation

[0024] The present invention will now be further described with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments. Specific conditions not specified in the embodiments are performed according to conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, all reagents or instruments used are conventional products obtained through commercial channels.

[0025] In the preparation examples of this invention, the average diameter of the hydroxylated carbon nanotubes is 70-80 nm.

[0026] Preparation Example 1 A functional monomer, prepared as follows: (1) Cystamine dihydrochloride, 1-formaldehyde piperazine, glacial acetic acid, and anhydrous ethanol were used in a ratio of 1 mmol: 2.1 mmol: 0.4 mmol: 4 mL. Cystamine dihydrochloride (CAS: 56-17-7) was dissolved in anhydrous ethanol, 1-formaldehyde piperazine and glacial acetic acid were added, and the mixture was reacted under reflux for 9 h. The solvent was removed under reduced pressure, and the mixture was cooled with ice water. The precipitate was filtered, washed with deionized water, and recrystallized from ethanol to obtain intermediate 1 (yield 87.5%). The NMR and mass spectrometry results of intermediate 1 were as follows: 1 HNMR: (C 14 H 28 N6S2, 400MHz, DMSO- d6 ) δ: 1.07 (s, 2H), 1.79-1.83 (t, 4H), 2.58-2.62 (t, 4H), 2.77-2.81 (t, 8H), 3.59-3.63 (t, 8H), 7.15 (s, 2H). MS (ESI) m / z=344.18 [M].

[0027] (2) With intermediate 1, vinyl chloroacetate, sodium bicarbonate, and tetrahydrofuran in a ratio of 10 mmol: 26 mmol: 28 mmol: 45 mL, intermediate 1, vinyl chloroacetate, and sodium bicarbonate were added to tetrahydrofuran. After reacting at room temperature for 22 h, the mixture was filtered, the solvent was removed by rotary evaporation, and the residue was purified by column chromatography (V... 甲醇 V 二氯甲烷 V 三乙胺 =5:95:0.5), yielding a functional monomer (yield 72.9%); the NMR and mass spectrometry results of the functional monomer are as follows: 1 HNMR: (C 22 H 36 N6O4S2, 400MHz, DMSO- d6) δ: 1.79-1.83 (t, 4H), 2.44-2.48 (t, 8H), 2.58-2.62 (t, 4H), 3.30 (s, 4H), 3.57-3. 61 (t, 8H), 4.53-4.57 (dd, 2H), 4.83-4.87 (dd, 2H), 7.15 (s, 2H), 7.23-7.27 (t, 2H). MS (ESI) m / z=512.22 [M].

[0028] Preparation Example 2 A functional monomer, prepared as follows: (1) Cystamine dihydrochloride, 1-formaldehyde piperazine, glacial acetic acid and anhydrous ethanol were used in a ratio of 1 mmol: 2 mmol: 0.3 mmol: 3 mL. Cystamine dihydrochloride was dissolved in anhydrous ethanol, 1-formaldehyde piperazine and glacial acetic acid were added, and the mixture was reacted under reflux for 8 h. The solvent was removed under reduced pressure, ice water was added to cool the mixture, the precipitate was filtered, washed with deionized water, and recrystallized from ethanol to obtain intermediate 1 (yield of 85.1%). The NMR and mass spectrometry results of intermediate 1 were consistent with those of preparation example 1.

[0029] (2) With intermediate 1, vinyl chloroacetate, sodium bicarbonate, and tetrahydrofuran in a ratio of 10 mmol: 25 mmol: 27 mmol: 40 mL, intermediate 1, vinyl chloroacetate, and sodium bicarbonate were added to tetrahydrofuran. After reacting at room temperature for 20 h, the mixture was filtered, the solvent was removed by rotary evaporation, and the residue was purified by column chromatography (V... 甲醇 V 二氯甲烷 V 三乙胺 =5:95:0.5), yielding a functional monomer (yield of 69.4%); the NMR and mass spectrometry results of the functional monomer were consistent with those of Preparation Example 1.

[0030] Preparation Example 3 A functional monomer, prepared as follows: (1) Cystamine dihydrochloride, 1-formaldehyde piperazine, glacial acetic acid and anhydrous ethanol were used in a ratio of 1 mmol: 2.2 mmol: 0.5 mmol: 5 mL. Cystamine dihydrochloride was dissolved in anhydrous ethanol, 1-formaldehyde piperazine and glacial acetic acid were added, and the mixture was reacted under reflux for 10 h. The solvent was removed under reduced pressure, ice water was added to cool the mixture, the precipitate was filtered, washed with deionized water, and recrystallized from ethanol to obtain intermediate 1 (yield of 84.7%). The NMR and mass spectrometry results of intermediate 1 were consistent with those of preparation example 1.

[0031] (2) With intermediate 1, vinyl chloroacetate, sodium bicarbonate, and tetrahydrofuran in a ratio of 10 mmol: 27 mmol: 30 mmol: 50 mL, intermediate 1, vinyl chloroacetate, and sodium bicarbonate were added to tetrahydrofuran. After reacting at room temperature for 24 h, the mixture was filtered, the solvent was removed by rotary evaporation, and the residue was purified by column chromatography (V... 甲醇 V 二氯甲烷 V 三乙胺 =5:95:0.5), to obtain the functional monomer (yield 70.3%); the NMR and mass spectrometry results of the functional monomer were consistent with those of Preparation Example 1.

[0032] Preparation Example 4 A modified polyacrylic acid resin is prepared as follows: S1. Weigh out the raw materials with AIBN, ethyl methacrylate, butyl methacrylate, isobornyl acrylate, the functional monomer of Preparation Example 1, and ethyl acetate in a mass ratio of 1:22:13:3:1:55 and set aside. Mix ethyl methacrylate, butyl methacrylate, isobornyl acrylate, the functional monomer of Preparation Example 1, and ethyl acetate to obtain mixed solution 1. Take 3 / 10 of the mixed solution 1 and heat it to 75°C under a nitrogen atmosphere to obtain mixed solution 2. S2. Mix the remaining mixed solution 1 with 7 / 10 of azobisisobutyronitrile (AIBN) to obtain mixed solution 3; add mixed solution 3 dropwise to mixed solution 2 over a period of 4 hours, keep the reaction at a constant temperature for 1.5 hours, add the remaining AIBN, raise the temperature to 85°C and continue the reaction for 4 hours, cool to below 60°C, adjust the solid content to 48%, and discharge the product.

[0033] Preparation Example 5 A modified polyacrylic acid resin is prepared as follows: S1. The raw materials, namely benzoyl peroxide, ethyl methacrylate, butyl methacrylate, isobornyl acrylate, the functional monomer of Preparation Example 2, and ethyl acetate, were weighed in a mass ratio of 1:20:10:1:0.5:50 and set aside. The ethyl methacrylate, butyl methacrylate, isobornyl acrylate, the functional monomer of Preparation Example 2, and ethyl acetate were mixed to obtain mixed solution 1. 1 / 4 of the mixed solution 1 was taken and heated to 70°C under a nitrogen atmosphere to obtain mixed solution 2. S2. Mix the remaining mixed solution 1 with 2 / 3 of the benzoyl peroxide to obtain mixed solution 3; add mixed solution 3 dropwise to mixed solution 2 over 3 hours, keep the reaction at the temperature for 1 hour, add the remaining benzoyl peroxide, raise the temperature to 80°C and continue the reaction for 5 hours, cool to below 60°C, adjust the solid content to 45%, and discharge the product.

[0034] Preparation Example 6 A modified polyacrylic acid resin is prepared as follows: S1. Weigh out the raw materials with AIBN, ethyl methacrylate, butyl methacrylate, isobornyl acrylate, the functional monomer of Preparation Example 3, and ethyl acetate in a mass ratio of 1:25:15:5:2.5:60 and set aside. Mix ethyl methacrylate, butyl methacrylate, isobornyl acrylate, the functional monomer of Preparation Example 3, and ethyl acetate to obtain mixed solution 1. Take 1 / 3 of the mixed solution 1 and heat it to 80°C under a nitrogen atmosphere to obtain mixed solution 2. S2. Mix the remaining mixed solution 1 with 3 / 4 of the AIBN to obtain mixed solution 3; add mixed solution 3 dropwise to mixed solution 2 over a period of 5 hours, keep the reaction at a constant temperature for 2 hours, add the remaining AIBN, raise the temperature to 90°C and continue the reaction for 2.5 hours, cool to below 60°C, adjust the solid content to 50%, and discharge the material.

[0035] Preparation Example 7 The difference between Preparation Example 7 and Preparation Example 4 is that the functional monomer of Preparation Example 1 is omitted, while the rest is the same as Preparation Example 4.

[0036] Preparation Example 8 A flame-retardant carbon nanotube is prepared as follows: (1) The hydroxylated carbon nanotubes, 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid, p-toluenesulfonic acid and DMF were used in a ratio of 1g:1g:0.08g:45mL. The hydroxylated carbon nanotubes were dispersed in N,N-dimethylformamide (DMF). Then p-toluenesulfonic acid and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid (CAS: 408307-69-7) were added. After reacting at 108℃ for 4h, the mixture was filtered, washed with ethanol and deionized water in sequence, and dried under vacuum to obtain amination carbon nanotubes. (2) Amine carbon nanotubes were dispersed in propanol at a ratio of 1 g: 3 g: 50 mL, followed by the addition of 2-bromoethylphosphonate diethyl ester. The mixture was reacted at 65 °C for 14 h, filtered, washed successively with ethanol and deionized water, and vacuum dried to obtain flame-retardant carbon nanotubes. SEM images of the flame-retardant carbon nanotubes are shown below. Figure 1 .

[0037] Preparation Example 9 A flame-retardant carbon nanotube is prepared as follows: (1) The hydroxylated carbon nanotubes, 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid, p-toluenesulfonic acid and DMF were used in a ratio of 1g:0.9g:0.06g:40mL. The hydroxylated carbon nanotubes were dispersed in DMF, and then p-toluenesulfonic acid and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid were added. After reacting at 105℃ for 5h, the mixture was filtered, washed with ethanol and deionized water in sequence, and dried under vacuum to obtain amination carbon nanotubes. (2) The ratio of amination carbon nanotubes, diethyl 2-bromoethylphosphonate and propanol was 1g:2.7g:40mL. The amination carbon nanotubes were dispersed in propanol, and then diethyl 2-bromoethylphosphonate was added. After reacting at 60℃ for 16h, the mixture was filtered, washed with ethanol and deionized water in sequence, and dried under vacuum to obtain flame-retardant carbon nanotubes.

[0038] Preparation Example 10 A flame-retardant carbon nanotube is prepared as follows: (1) The hydroxylated carbon nanotubes, 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid, p-toluenesulfonic acid and DMF were used in a ratio of 1g:1.2g:0.1g:50mL. The hydroxylated carbon nanotubes were dispersed in DMF, and then p-toluenesulfonic acid and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid were added. After reacting at 110℃ for 3h, the mixture was filtered, washed with ethanol and deionized water in sequence, and dried under vacuum to obtain amination carbon nanotubes. (2) The ratio of amination carbon nanotubes, diethyl 2-bromoethylphosphonate and propanol was 1g:3.5g:60mL. The amination carbon nanotubes were dispersed in propanol, and then diethyl 2-bromoethylphosphonate was added. After reacting at 70℃ for 12h, the mixture was filtered, washed with ethanol and deionized water in sequence, and dried under vacuum to obtain flame-retardant carbon nanotubes.

[0039] Example 1 A wear-resistant and flame-retardant transfer coating comprises, by weight, the following raw materials: 16 parts of modified polyacrylic acid resin of Preparation Example 4, 7 parts of cellulose acetate, 50 parts of ethyl acetate, 0.1 parts of BYK-066N, 0.18 parts of BYK-306, 0.09 parts of polyoxyethylene alkyl ether, and 6 parts of flame-retardant carbon nanotubes of Preparation Example 8.

[0040] The preparation method of the above-mentioned wear-resistant and flame-retardant transfer coating includes the following steps: Mix all ingredients thoroughly to obtain the final product.

[0041] Example 2 A wear-resistant and flame-retardant transfer coating comprises, by weight, the following raw materials: 10 parts of modified polyacrylic acid resin of Preparation Example 5, 5 parts of cellulose acetate butyrate, 45 parts of n-butyl acetate, 0.05 parts of BYK-051, 0.1 parts of BYK-333, 0.05 parts of polyoxyethylene alkyl ether, and 3 parts of flame-retardant carbon nanotubes of Preparation Example 9.

[0042] The preparation method of the above-mentioned wear-resistant and flame-retardant transfer coating includes the following steps: Mix all ingredients thoroughly to obtain the final product.

[0043] Example 3 A wear-resistant and flame-retardant transfer coating comprises, by weight, the following raw materials: 25 parts of modified polyacrylic acid resin of Preparation Example 6, 10 parts of cellulose acetate propionate, 60 parts of propylene glycol monomethyl ether, 0.2 parts of BYK-052, 0.25 parts of BYK-323, 0.1 parts of polyoxyethylene alkyl ether, and 7 parts of flame-retardant carbon nanotubes of Preparation Example 10.

[0044] The preparation method of the above-mentioned wear-resistant and flame-retardant transfer coating includes the following steps: Mix all ingredients thoroughly to obtain the final product.

[0045] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that hydroxylated carbon nanotubes were used instead of the flame-retardant carbon nanotubes used in Preparation Example 8.

[0046] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the modified polyacrylic resin of Preparation Example 7 was used instead of the modified polyacrylic resin of Preparation Example 4.

[0047] Experimental Example 1 The antibacterial properties of each coating were tested according to HG / T 3950-2025 "Antibacterial and Antiviral Coatings", and the test results are shown in Table 1.

[0048] Table 1 As shown in Table 1, Examples 1-3 all achieved antibacterial rates of over 99% against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, demonstrating excellent antibacterial properties. Compared to Example 1, Comparative Example 1, which replaced the flame-retardant carbon nanotubes of the present invention with hydroxylated carbon nanotubes, showed a significant decrease in antibacterial rate, proving that the quaternary ammonium salt groups grafted onto the surface of the flame-retardant carbon nanotubes are the key structure that imparts antibacterial properties to the coating.

[0049] Experimental Example 2 The coatings obtained from the examples or comparative examples were coated onto PET films, molded, and metallized to obtain the corresponding packaging materials, which were then subjected to the following performance tests: Limiting oxygen index: Tested according to GB / T 2406.2-2009, the results are shown in Table 2; Wear resistance: The Taber rotary wear tester was used for testing. The load was 2.5N, the grinding wheel was H18, the rotation speed was 60r / min, and the mass loss of each material was tested after 50 revolutions. The results are shown in Table 2. Peel strength: Tested according to GB / T 2791-1995, the results are shown in Table 2.

[0050] Table 2 As shown in Table 2, the limiting oxygen index of Examples 1-3 is higher than 21%, exhibiting good flame retardant properties. In Comparative Example 1, after replacing the flame-retardant carbon nanotubes with hydroxylated carbon nanotubes, the limiting oxygen index decreased significantly, proving that the nitrogen-phosphorus intumescent flame-retardant system formed by the phosphate esters grafted onto the surface of the flame-retardant carbon nanotubes and the quaternary ammonium groups is the key to imparting excellent flame retardancy to the coating.

[0051] The wear resistance of Examples 1-3 was only 0.2-0.3 mg, demonstrating excellent wear resistance. The wear resistance of Comparative Example 2 reached 1.8 mg, which was much higher than that of Example 1, indicating that functional monomers can significantly improve the wear resistance of coatings, which is largely related to the rigid structural units disulfide bonds and piperazine rings in their molecules.

[0052] The peel strength of Examples 1-3 was 2.1-2.7 N / 15 mm, indicating a strong bond between the coating and the aluminum plating layer. The peel strength of Comparative Example 2 was significantly lower than that of Example 1, demonstrating that the addition of functional monomers can improve the adhesion of the coating. This may be because the polar groups in the functional monomers (such as piperazine rings and Schiff base groups) can coordinate with aluminum atoms, thereby effectively improving the interfacial compatibility and adhesion between the coating and the aluminum plating layer.

[0053] In summary, this application, by introducing flame-retardant carbon nanotubes with a specific structure and modified polyacrylic resin containing functional monomers, enables the transfer coating to possess excellent antibacterial properties, flame retardant properties, abrasion resistance, and adhesion.

[0054] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A wear-resistant and flame-retardant transfer coating, characterized in that, By weight, it includes the following raw materials: 10-25 parts modified polyacrylic acid resin, 5-10 parts cellulose resin, 45-60 parts solvent, 3-7 parts flame retardant carbon nanotubes, 0.05-0.2 parts defoamer, 0.1-0.25 parts leveling agent, and 0.05-0.1 parts wetting agent; The preparation process of the flame-retardant carbon nanotubes is as follows: (1) Hydroxylated carbon nanotubes were added to N,N-dimethylformamide, and then a catalyst and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid were added. After the reaction, the mixture was purified to obtain amination carbon nanotubes. (2) The amination carbon nanotubes were added to propanol, and then 2-bromoethylphosphonic acid diethyl ester was added. After the reaction, the mixture was purified to obtain the flame-retardant carbon nanotubes.

2. The wear-resistant and flame-retardant transfer coating according to claim 1, characterized in that, The catalyst in step (1) is p-toluenesulfonic acid; the mass ratio of the hydroxylated carbon nanotubes, the catalyst, and 3-(dimethylamino)-2-[(dimethylamino)methyl]propionic acid is 1:(0.9-1.2):(0.06-0.1); the reaction temperature is 105-110℃ and the time is 3-5h.

3. The wear-resistant and flame-retardant transfer coating according to claim 1, characterized in that, In step (2), the mass ratio of amination of carbon nanotubes to diethyl 2-bromoethylphosphonate is 1:(2.7-3.5); the reaction temperature is 60-70℃ and the reaction time is 12-16h.

4. The wear-resistant and flame-retardant transfer coating according to claim 1, characterized in that, The preparation process of the modified polyacrylic acid resin is as follows: S1. Mix ethyl methacrylate, butyl methacrylate, isobornyl acrylate, functional monomer and ethyl acetate to obtain mixed solution 1; take 1 / 4 to 1 / 3 of the mixed solution 1, heat it to obtain mixed solution 2; S2. Mix the remaining mixed solution 1 with 2 / 3-3 / 4 of the initiator to obtain mixed solution 3; add mixed solution 3 to mixed solution 2, keep it at a warm temperature for reaction, then add the remaining initiator for heating reaction, cool, adjust the solid content, and discharge to obtain the final product; The structure of the functional unit mentioned in step S1 is as follows: 。 5. The wear-resistant and flame-retardant transfer coating according to claim 4, characterized in that, In step S1, the mass ratio of ethyl methacrylate, butyl methacrylate, isobornyl acrylate, functional monomer, and ethyl acetate is (20-25):(10-15):(1-5):(0.5-2.5):(50-60); the heating temperature is 70-80℃; in step S2, the initiator is azobisisobutyronitrile or benzoyl peroxide; based on the total amount of ethyl methacrylate used, the mass ratio of the initiator to ethyl methacrylate is 1:(20-25); the heat preservation reaction time is 1-2 hours; the heating reaction temperature is 80-90℃, and the time is 2.5-5 hours; the solid content is adjusted to 45-50%.

6. The wear-resistant and flame-retardant transfer coating according to claim 5, characterized in that, The preparation method of the functional monomer is as follows: (a) Cystamine dihydrochloride was added to anhydrous ethanol, followed by the addition of 1-formaldehyde piperazine and glacial acetic acid. The mixture was refluxed and purified to obtain intermediate 1. The structural formula of intermediate 1 is: (b) The intermediate 1, vinyl chloroacetate, and sodium bicarbonate were added to tetrahydrofuran, and the mixture was purified after reaction to obtain the functional monomer.

7. The wear-resistant and flame-retardant transfer coating according to claim 6, characterized in that, In step (a), the molar ratio of cystamine dihydrochloride, 1-formaldehyde piperazine, and glacial acetic acid is 1:(2-2.2):(0.3-0.5); the reflux reaction time is 8-10 h; in step (b), the molar ratio of intermediate 1, vinyl chloroacetate, and sodium bicarbonate is 1:(2.5-2.7):(2.7-3); the reaction time is 20-24 h.

8. The wear-resistant and flame-retardant transfer coating according to claim 1, characterized in that, The cellulose resin is selected from cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate; the defoamer is selected from BYK-066N, BYK-051, and BYK-052; the wetting agent is polyoxyethylene alkyl ether; the leveling agent is selected from BYK-306, BYK-333, and BYK-323; and the solvent is selected from ethyl acetate, n-butyl acetate, n-propyl acetate, ethanol, isopropanol, butanone, propylene glycol monomethyl ether, and propylene glycol ethyl ether.

9. A method for preparing the wear-resistant and flame-retardant transfer coating according to any one of claims 1-8, characterized in that, Includes the following steps: Mix all ingredients thoroughly to obtain the final product.

10. The application of the wear-resistant and flame-retardant transfer coating according to any one of claims 1-8, characterized in that, It is used in the packaging industry.

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