Preparation method of high-strength light-emitting transparent coating

Abstract

The invention relates to the technical field of coatings, and discloses a preparation method of a high-strength light-emitting transparent coating, which comprises the following steps: mixing and stirring modified polyurethane, epoxidized pentaerythritol methyl silicate, a high-light transparent polyurethane emulsion, a propylene glycol coalescing agent, a polysiloxane defoaming agent, a zinc sulfide pigment, an ammonium acrylate wetting agent and water, and uniformly stirring to obtain the high-strength light-emitting transparent coating. And standing at normal temperature to obtain the high-strength luminous transparent coating. In the stirring process, a terminal hydroxyl group in the modified polyurethane and an epoxy group in the epoxidized pentaerythritol methyl silicate are subjected to a ring-opening reaction, so that the compatibility between the modified polyurethane and the epoxy group is improved, and meanwhile, the modified polyurethane and the epoxy group are crosslinked to form a crosslinked network, so that the mechanical property of the modified polyurethane is improved; a quaternary ammonium salt group and an imidazole group in the modified polyurethane have a relatively good antibacterial effect. A silicon element, a sulfur element and a sodium sulfonate group in the modified polyurethane and the pentaerythritol methyl silicate have relatively good flame-retardant effects and jointly form a flame-retardant system.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, in particular to a method for preparing a high-intensity luminous transparent coating. Background Art

[0002] High-intensity luminous transparent coating is a coating with special functions, which can emit bright light while maintaining transparency. This coating is usually made of specific materials, such as fluorescent pigments, photoluminescent materials or other substances that can absorb and re-emit light. For example, patent CN105152546B discloses a transparent antifouling coating material for glass, a transparent antifouling coating and a preparation method thereof. The hydrophobic coating material and its preparation method provided by the invention have few equipment requirements, non-toxic raw materials, low use costs, and can be used to prepare large-area transparent antifouling coatings; the obtained coating has excellent hydrophobicity, transparency, antifouling and repeated wiping properties; but its flame retardant and antibacterial effects are not improved. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies of the prior art, the present invention provides a method for preparing a high-intensity luminous transparent coating, which has good flame retardant, tensile and antibacterial effects.

[0005] (II) Technical solution

[0006] To achieve the above object, the present invention provides the following technical solution: a method for preparing a high-intensity luminous transparent coating, the method for preparing the high-intensity luminous transparent coating is:

[0007] (1) Adding diallyl bisphenol A to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptosuccinic acid and benzoin dimethyl ether photoinitiator, irradiating with 365 nm ultraviolet light at 30-50° C. for 3-4 hours, centrifuging, washing and drying to obtain intermediate 1;

[0008] (2) adding intermediate 1 and 1-(2-hydroxyethyl)imidazole to N,N-dimethylformamide solvent, stirring and dissolving, adding p-toluenesulfonic acid catalyst, and carrying out esterification reaction at 75-100° C. for 6-8 hours. After completion, distilling under reduced pressure, washing and drying to obtain intermediate 2;

[0009] (3) adding intermediate 2 and sodium 3-chloro-2-hydroxypropanesulfonate to a 5-7% sodium hydroxide aqueous solution to carry out a quaternization reaction at 40-65° C. for 6-8 hours, cooling after the reaction, adding dilute hydrochloric acid dropwise to adjust the pH to 7, and then evaporating to obtain an imidazole chain extender;

[0010] (4) removing water from the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 55-80° C. for 2-4 hours to perform prepolymerization, then adding an imidazole chain extender, stirring to continue the chain extension reaction, reacting at 40-60° C. for 1-2 hours, and after the reaction is completed, cooling and discharging to obtain a modified polyurethane;

[0011] (5) adding magnolol, pentaerythritol methyl silicate, and adipoyl chloride to N,N-dimethylacetamide solvent, stirring and mixing, and continuously adding pyridine catalyst thereto, reacting at 60-80° C. for 1-3 h, and obtaining modified magnolol after completion;

[0012] (6) adding 3-6 parts by weight of modified magnolol to an acetone solvent, stirring evenly, and then adding 10-14 parts by weight of an aqueous hydrogen peroxide solution to the acetone solvent to carry out the reaction. After the reaction is completed, the acetone solvent is distilled under reduced pressure, filtered and dried to obtain epoxidized pentaerythritol methyl silicate.

[0013] (7) 8-12 parts by weight of modified polyurethane, 6-10 parts by weight of epoxidized pentaerythritol methyl silicate, 12-15 parts by weight of high-gloss transparent polyurethane emulsion, 1-2 parts by weight of propylene glycol film-forming aid, 0.2-0.3 parts by weight of polysiloxane defoamer, 1-2 parts by weight of zinc sulfide pigment, 0.3-0.5 parts by weight of ammonium acrylate wetting agent, and 10-14 parts by weight of water are mixed and stirred, and after stirring evenly, the mixture is allowed to stand at room temperature for 3-5 hours to obtain a high-intensity luminous transparent coating.

[0014] Preferably, the mass ratio of diallyl bisphenol A, mercaptosuccinic acid and benzoin dimethyl ether photoinitiator in (1) is 1:1.3-1.5:0.01-0.03.

[0015] Preferably, the mass ratio of the intermediate 1, 1-(2-hydroxyethyl)imidazole and p-toluenesulfonic acid catalyst in (2) is 1:1.1-1.3:0.02-0.03.

[0016] Preferably, the mass ratio of the intermediate 2:3-chloro-2-hydroxypropanesulfonate in (3) is 1:1.2-1.4.

[0017] Preferably, the mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and imidazole chain extender in (4) is 1.2-1.5:1:0.01-0.02:0.4-0.7.

[0018] Preferably, the mass ratio of magnolol, pentaerythritol methyl silicate, adipoyl chloride and pyridine catalyst in (5) is 1:1.6-1.8:0.8-1.2:0.01-0.03.

[0019] Preferably, the reaction temperature in (6) is 30-45°C.

[0020] Preferably, the reaction time in (6) is 4-7 hours.

[0021] (III) Beneficial technical effects

[0022] The invention obtains a high-strength luminous transparent coating by mixing and stirring modified polyurethane, epoxidized pentaerythritol methyl silicate, high-gloss transparent polyurethane emulsion, propylene glycol film-forming aid, polysiloxane defoamer, zinc sulfide pigment, ammonium acrylate wetting agent and water, stirring evenly, and standing at room temperature.

[0023] During the stirring process, the terminal hydroxyl groups in the modified polyurethane react with the epoxy groups in the epoxidized pentaerythritol methyl silicate to open the ring, thereby increasing the compatibility between the two, and at the same time, cross-linking occurs between the two to form a cross-linked network, thereby increasing the mechanical properties; the quaternary ammonium salt groups and imidazole groups in the modified polyurethane have good antibacterial effects, and the intermediate 1 reacts with 1-(2-hydroxyethyl)imidazole to increase the substitution degree of imidazole, thereby making the antibacterial effect better. The silicon element, sulfur element, and sodium sulfonate groups in the modified polyurethane and pentaerythritol methyl silicate have good flame retardant effects, and together constitute a flame retardant system. DETAILED DESCRIPTION

[0024] Example 1

[0025] (1) Adding diallyl bisphenol A to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptosuccinic acid and benzoin dimethyl ether photoinitiator, wherein the mass ratio of diallyl bisphenol A, mercaptosuccinic acid, and benzoin dimethyl ether photoinitiator is 1:1.3:0.01, irradiating with 365 nm ultraviolet light at 30° C. for 3 h, centrifuging after irradiation, washing and drying to obtain intermediate 1;

[0026] (2) adding intermediate 1 and 1-(2-hydroxyethyl)imidazole to N,N-dimethylformamide solvent, stirring and dissolving, and continuously adding p-toluenesulfonic acid catalyst, wherein the mass ratio of intermediate 1, 1-(2-hydroxyethyl)imidazole and p-toluenesulfonic acid catalyst is 1:1.1:0.02, and carrying out esterification reaction at 75° C. for 6 hours. After completion, distillation under reduced pressure is performed, and the product is washed and dried to obtain intermediate 2;

[0027] (3) adding intermediate 2 and sodium 3-chloro-2-hydroxypropanesulfonate to a 5% sodium hydroxide aqueous solution, wherein the mass ratio of intermediate 2 to sodium 3-chloro-2-hydroxypropanesulfonate is 1:1.2, reacting at 40° C. for 6 h, cooling after the reaction, adding dilute hydrochloric acid dropwise to adjust the pH to 7, and then evaporating to obtain an imidazole chain extender;

[0028] (4) removing water from the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 55° C. for 2 hours, performing prepolymerization, and then adding an imidazole chain extender, wherein the mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and imidazole chain extender is 1.2:1:0.01:0.4, stirring to continue the chain extension reaction, reacting at 40° C. for 1 hour, cooling and discharging after the reaction to obtain a modified polyurethane;

[0029] (5) Add magnolol, pentaerythritol methyl silicate, and adipoyl chloride to N,N-dimethylacetamide solvent, stir and mix, and continue to add pyridine catalyst, wherein the mass ratio of magnolol, pentaerythritol methyl silicate, adipoyl chloride, and pyridine catalyst is 1:1.6:0.8:0.01, react at 60° C. for 1 hour, and obtain modified magnolol after completion;

[0030] (6) adding 3 parts by weight of modified magnolol to an acetone solvent, stirring evenly, adding 10 parts by weight of an aqueous hydrogen peroxide solution thereto, reacting at 30° C. for 4 hours, and then distilling under reduced pressure, filtering and drying to obtain epoxidized pentaerythritol methyl silicate;

[0031] (7) 8 parts by weight of modified polyurethane, 6 parts by weight of epoxidized pentaerythritol methyl silicate, 12 parts by weight of high-gloss transparent polyurethane emulsion, 1 part by weight of propylene glycol film-forming aid, 0.2 parts by weight of polysiloxane defoamer, 1 part by weight of zinc sulfide pigment, 0.3 parts by weight of ammonium acrylate wetting agent, and 10 parts by weight of water are mixed and stirred, and after stirring evenly, the mixture is allowed to stand at room temperature for 3 hours to obtain a high-intensity luminous transparent coating.

[0032] Example 2

[0033] (1) Adding diallyl bisphenol A to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptosuccinic acid and benzoin dimethyl ether photoinitiator, wherein the mass ratio of diallyl bisphenol A, mercaptosuccinic acid, and benzoin dimethyl ether photoinitiator is 1:1.5:0.03, irradiating with 365 nm ultraviolet light at 50° C. for 4 h, centrifuging after irradiation, washing and drying to obtain intermediate 1;

[0034] (2) adding intermediate 1 and 1-(2-hydroxyethyl)imidazole to N,N-dimethylformamide solvent, stirring and dissolving, and continuously adding p-toluenesulfonic acid catalyst, wherein the mass ratio of intermediate 1, 1-(2-hydroxyethyl)imidazole and p-toluenesulfonic acid catalyst is 1:1.3:0.03, and carrying out esterification reaction at 100° C. for 8 hours, and then distilling under reduced pressure, washing and drying to obtain intermediate 2;

[0035] (3) adding intermediate 2 and sodium 3-chloro-2-hydroxypropanesulfonate to a 7% sodium hydroxide aqueous solution, wherein the mass ratio of intermediate 2 to sodium 3-chloro-2-hydroxypropanesulfonate is 1:1.4, reacting at 65° C. for 8 h, cooling after the reaction, adding dilute hydrochloric acid dropwise to adjust the pH to 7, and then evaporating to obtain an imidazole chain extender;

[0036] (4) removing water from the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 80° C. for 4 hours, performing prepolymerization, and then adding an imidazole chain extender, wherein the mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and imidazole chain extender is 1.5:1:0.02:0.7, stirring to continue the chain extension reaction, reacting at 60° C. for 2 hours, cooling and discharging after the reaction to obtain a modified polyurethane;

[0037] (5) adding magnolol, pentaerythritol methyl silicate, and adipoyl chloride to N,N-dimethylacetamide solvent, stirring and mixing, and continuously adding pyridine catalyst thereto, wherein the mass ratio of magnolol, pentaerythritol methyl silicate, adipoyl chloride, and pyridine catalyst is 1:1.8:1.2:0.03, reacting at 80° C. for 3 h, and obtaining modified magnolol after completion;

[0038] (6) adding 6 parts by weight of modified magnolol to an acetone solvent, stirring evenly, adding 14 parts by weight of an aqueous hydrogen peroxide solution thereto, reacting at 45° C. for 7 hours, and then distilling under reduced pressure, filtering and drying to obtain epoxidized pentaerythritol methyl silicate;

[0039] (7) 12 parts by weight of modified polyurethane, 10 parts by weight of epoxidized pentaerythritol methyl silicate, 15 parts by weight of high-gloss transparent polyurethane emulsion, 2 parts by weight of propylene glycol film-forming aid, 0.3 parts by weight of polysiloxane defoaming agent, 2 parts by weight of zinc sulfide pigment, 0.5 parts by weight of ammonium acrylate wetting agent, and 14 parts by weight of water are mixed and stirred, and after stirring evenly, the mixture is allowed to stand at room temperature for 5 hours to obtain a high-intensity luminous transparent coating.

[0040] Example 3

[0041] (1) Adding diallyl bisphenol A to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptosuccinic acid and benzoin dimethyl ether photoinitiator, wherein the mass ratio of diallyl bisphenol A, mercaptosuccinic acid, and benzoin dimethyl ether photoinitiator is 1:1.4:0.02, irradiating with 365 nm ultraviolet light at 40° C. for 3 h, centrifuging after irradiation, washing and drying to obtain intermediate 1;

[0042] (2) adding intermediate 1 and 1-(2-hydroxyethyl)imidazole to N,N-dimethylformamide solvent, stirring and dissolving, and continuously adding p-toluenesulfonic acid catalyst, wherein the mass ratio of intermediate 1, 1-(2-hydroxyethyl)imidazole and p-toluenesulfonic acid catalyst is 1:1.2:0.03, and performing esterification reaction at 100° C. for 6 hours. After completion, performing reduced pressure distillation, washing and drying to obtain intermediate 2;

[0043] (3) adding intermediate 2 and sodium 3-chloro-2-hydroxypropanesulfonate to a 6% sodium hydroxide aqueous solution, wherein the mass ratio of intermediate 2 to sodium 3-chloro-2-hydroxypropanesulfonate is 1:1.3, reacting at 55° C. for 7 h, cooling after the reaction, adding dilute hydrochloric acid dropwise to adjust the pH to 7, and then evaporating to obtain an imidazole chain extender;

[0044] (4) removing water from the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 65° C. for 3 hours, performing prepolymerization, and then adding an imidazole chain extender, wherein the mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst, and imidazole chain extender is 1.4:1:0.01:0.6, stirring to continue the chain extension reaction, reacting at 50° C. for 1 hour, cooling and discharging after the reaction to obtain a modified polyurethane;

[0045] (5) adding magnolol, pentaerythritol methyl silicate, and adipoyl chloride to N,N-dimethylacetamide solvent, stirring and mixing, and continuously adding pyridine catalyst thereto, wherein the mass ratio of magnolol, pentaerythritol methyl silicate, adipoyl chloride, and pyridine catalyst is 1:1.7:1.0:0.02, reacting at 70° C. for 2 h, and obtaining modified magnolol after completion;

[0046] (6) adding 5 parts by weight of modified magnolol to an acetone solvent, stirring evenly, adding 12 parts by weight of an aqueous hydrogen peroxide solution thereto, reacting at 35° C. for 6 hours, and then distilling under reduced pressure, filtering and drying to obtain epoxidized pentaerythritol methyl silicate;

[0047] (7) 10 parts by weight of modified polyurethane, 8 parts by weight of epoxidized pentaerythritol methyl silicate, 14 parts by weight of high-gloss transparent polyurethane emulsion, 1 part by weight of propylene glycol film-forming aid, 0.3 parts by weight of polysiloxane defoaming agent, 1 part by weight of zinc sulfide pigment, 0.4 parts by weight of ammonium acrylate wetting agent, and 12 parts by weight of water are mixed and stirred, and after stirring evenly, the mixture is allowed to stand at room temperature for 4 hours to obtain a high-intensity luminous transparent coating.

[0048] Comparative Example 1

[0049] The difference between this comparative example and Example 3 is that no modified polyurethane is added.

[0050] Comparative Example 2

[0051] This comparative example is compared with Example 3, except that no epoxidized pentaerythritol methyl silicate is added.

[0052] Use an oxygen index meter to test the limiting oxygen index of the coating; use a horizontal and vertical combustion instrument to test the combustion level of the coating.

[0053] Table 1: Flame retardancy tests.

[0054] project Limiting oxygen index (%) Combustion level Example 1 30 V-0 Example 2 32 V-0 Example 3 31 V-0 Comparative Example 1 20 V-1 Comparative Example 2 21 V-1

[0055] It can be seen from Table 1 that the flame retardant effect of Examples 1-3 is better than that of Comparative Examples 1-2, which indicates that the coating prepared by the present invention has a good flame retardant effect.

[0056] The mechanical properties of the coating were tested using a universal electronic testing machine with a tensile rate of 100 mm / min.

[0057] Table 2: Tensile strength test.

[0058]

[0059]

[0060] It can be seen from Table 2 that the tensile effect of Examples 1-3 is better than that of Comparative Examples 1-2, and the coating prepared by the present invention has better tensile strength.

[0061] Antibacterial performance: Carefully tear off the coating and cut it into a 10mm diameter disc, sterilize it with a UV lamp, add it to 10mL solid agar medium and culture it with Staphylococcus aureus (10μL, 106CFU / mL) in a 37℃ incubator for 12 hours. The experiment uses three groups of parallel controls and takes the average value. The blank control is carried out without the coating, and then the CFU count is determined. The calculation formula of the antibacterial rate is shown as follows: Antibacterial rate (%) = (1-C / N) × 100%. Among them, N is the average number of live bacteria in the blank control group after 12h, and C is the average number of live bacteria in the experimental group after 12h. The test results are shown in Table 2.

[0062] Table 3: Antibacterial rate test.

[0063] project Antibacterial rate (%) Example 1 96.5 Example 2 99.6 Example 3 98.8 Comparative Example 1 72.1 Comparative Example 2 83.2

[0064] It can be seen from Table 3 that Examples 1-3 of the present invention have better antibacterial properties than Comparative Examples 1-2.

[0065] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing a high-intensity luminous transparent coating, characterized in that: The preparation method of the high-intensity luminous transparent coating is: (1) Adding diallyl bisphenol A to N,N-dimethylformamide solvent, stirring and dispersing, then adding mercaptosuccinic acid and benzoin dimethyl ether photoinitiator, irradiating with 365 nm ultraviolet light at 30-50° C. for 3-4 hours, centrifuging, washing and drying to obtain intermediate 1; (2) adding intermediate 1 and 1-(2-hydroxyethyl)imidazole to N,N-dimethylformamide solvent, stirring and dissolving, adding p-toluenesulfonic acid catalyst, and carrying out esterification reaction at 75-100° C. for 6-8 hours. After completion, distilling under reduced pressure, washing and drying to obtain intermediate 2; (3) adding intermediate 2 and sodium 3-chloro-2-hydroxypropanesulfonate to a 5-7% sodium hydroxide aqueous solution, reacting at 40-65° C. for 6-8 hours, cooling after the reaction, adding dilute hydrochloric acid dropwise to adjust the pH to 7, and then evaporating to obtain an imidazole chain extender; (4) removing water from the polyether diol and mixing it evenly with hexamethylene diisocyanate, introducing nitrogen, then dropping a dibutyltin dilaurate catalyst, reacting at 55-80° C. for 2-4 hours to perform prepolymerization, then adding an imidazole chain extender, stirring to continue the chain extension reaction, reacting at 40-60° C. for 1-2 hours, and after the reaction is completed, cooling and discharging to obtain a modified polyurethane; (5) adding magnolol, pentaerythritol methyl silicate, and adipoyl chloride to N,N-dimethylacetamide solvent, stirring and mixing, and continuously adding pyridine catalyst thereto, reacting at 60-80° C. for 1-3 h, and obtaining modified magnolol after completion; (6) adding 3-6 parts by weight of modified magnolol to an acetone solvent, stirring evenly, and then adding 10-14 parts by weight of an aqueous hydrogen peroxide solution to the acetone solvent to carry out the reaction. After the reaction is completed, the acetone solvent is distilled under reduced pressure, filtered and dried to obtain epoxidized pentaerythritol methyl silicate. (7) 8-12 parts by weight of modified polyurethane, 6-10 parts by weight of epoxidized pentaerythritol methyl silicate, 12-15 parts by weight of high-gloss transparent polyurethane emulsion, 1-2 parts by weight of propylene glycol film-forming aid, 1-2 parts by weight of zinc sulfide pigment, 0.2-0.3 parts by weight of polysiloxane defoamer, 0.3-0.5 parts by weight of ammonium acrylate wetting agent, and 10-14 parts by weight of water are mixed and stirred, and after stirring evenly, the mixture is allowed to stand at room temperature for 3-5 hours to obtain a high-intensity luminous transparent coating.

2. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The mass ratio of diallyl bisphenol A, mercaptosuccinic acid and benzoin dimethyl ether photoinitiator in (1) is 1:1.3-1.5:0.01-0.

03.

3. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The mass ratio of the intermediate 1, 1-(2-hydroxyethyl)imidazole and p-toluenesulfonic acid catalyst in (2) is 1:1.1-1.3:0.02-0.

03.

4. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The mass ratio of the intermediate 2:3-chloro-2-hydroxypropanesulfonate in (3) is 1:1.2-1.

4.

5. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The mass ratio of the polyether diol, hexamethylene diisocyanate, dibutyltin dilaurate catalyst and imidazole chain extender in (4) is 1.2-1.5:1:0.01-0.02:0.4-0.

7.

6. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The mass ratio of magnolol, pentaerythritol methyl silicate, adipoyl chloride and pyridine catalyst in (5) is 1:1.6-1.8:0.8-1.2:0.01-0.

03.

7. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The reaction temperature in (6) is 30-45°C.

8. The method for preparing a high-intensity luminous transparent coating according to claim 1, characterized in that: The reaction time in (6) is 4-7h.

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