Water-based silver powder paint for building installation pipeline and preparation method of water-based silver powder paint

Abstract

The invention discloses a building installation pipeline water-based silver powder paint and a preparation method thereof, and belongs to the technical field of coatings. The water-based silver powder paint comprises the following components in percentage by weight: 40-45% of modified water-based polyurethane resin, 20-23% of silver powder, 3-5% of imidazoline derivatives, 3-5% of a dispersing agent, 3-6% of a cosolvent, 2-5% of a weather-proof additive, 1-2% of a stabilizer and the balance of high-purity water. Through the synergistic effect of the modified waterborne polyurethane resin, the imidazoline derivative, the weather-resistant additive and other components, the waterborne silver powder paint has the following advantages of high glossiness, strong adhesive force and good weather resistance and storage stability. In addition, the water-based silver powder paint system is low in VOC content and free of pungent smell.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and in particular relates to a water-based silver powder paint for building installation pipelines and a preparation method thereof. Background Art

[0002] Silver powder paint is mainly composed of silver powder, resin, additives, etc. Silver powder is the key component of silver powder paint, which gives the paint a unique metallic luster. Resin is the matrix of the paint, responsible for bonding the silver powder and other additives together to form a tough protective film. Additives play a role in adjusting the performance of the paint, such as improving adhesion and anti-aging. With the increasing awareness of environmental protection, the development of silver powder paint pays more attention to environmental protection performance. Water-based silver powder paint, as an environmentally friendly paint, will become the mainstream in the future. Water-based silver powder paint has the advantages of low VOC emissions, non-toxic and harmless, which is in line with the development trend of green environmental protection.

[0003] In order to beautify and improve the durability of the substrate, silver paint is usually sprayed on the surface of these substrates. Although the construction installation pipeline has been painted with silver paint for a long time and the process is relatively mature, with the continuous development and progress of society and the enhancement of people's environmental awareness, higher requirements have been placed on the living environment, and higher requirements have been placed on the painting quality and brightness of silver paint. By studying the previous silver paint preparation process and improving this process, the silver paint has stronger adhesion than before, is not easy to fade, and has a long durability, which is conducive to improving the visual quality and can meet the needs of functional use and aesthetic concepts. Summary of the invention

[0004] The purpose of the present invention is to provide a water-based silver powder paint with strong adhesion, high gloss, good weather resistance and good storage stability and a preparation method thereof.

[0005] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0006] A water-based silver paint for building installation pipelines comprises the following raw materials: 40-45% of modified water-based polyurethane resin, 20-23% of silver powder, 3-5% of imidazoline derivatives, 3-5% of dispersant, 3-6% of cosolvent, 2-5% of weathering additive, 1-2% of stabilizer and 100% of high-purity water.

[0007] Furthermore, the preparation steps of the modified waterborne polyurethane resin are:

[0008] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0009] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system cools to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA dimethylethanolamine is added to obtain a modified waterborne polyurethane resin solution.

[0010] Furthermore, in the step S2, the molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO is 1:0.2:0.2:0.5; and the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in the step S2 is 1:5:0.5.

[0011] Furthermore, the modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0012] Furthermore, the dispersant is one or more of isomeric alcohol polyoxyethylene ether, polyoxyethylene glycol alkyl ester, alkylphenol polyethylene ether, polyoxyethylene alkyl ether, and condensate of ethylene glycol and ethylene oxide.

[0013] Furthermore, the co-solvent is one or more of ethylene glycol tert-butyl ether, dimethylformamide, ethylene glycol tert-butyl ether, and polyol ester.

[0014] Furthermore, the imidazoline derivative is heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:1.

[0015] Furthermore, the weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0016] Furthermore, the stabilizer is hydroxyethyl cellulose ether.

[0017] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0018] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0019] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0020] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0021] The raw materials used in the present invention are all commercially available.

[0022] Waterborne polyurethane resin uses water as solvent and does not contain organic solvent, so it is environmentally friendly and meets the demand for green chemicals in modern society. Compared with traditional solvent-based polyurethane resin, waterborne polyurethane resin has a lower VOC content, which reduces pollution to the atmosphere and harm to human health; in addition, waterborne polyurethane resin has good weather resistance and wear resistance. The modified waterborne polyurethane resin of the present invention modified by titanium dioxide can delay the aging process of the coating due to its excellent UV shielding performance, and can maintain gloss for a long time under outdoor conditions.

[0023] Silver powder provides technical luster; imidazoline derivatives are composed of heptadecaenylamine ethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline. Imidazoline derivatives have good chemical resistance and can resist the erosion of various chemical substances, thereby enhancing the corrosion resistance and weather resistance of the paint film; in addition, it enhances the adhesion between the paint film and the substrate, making the paint film more firm and not easy to fall off. Heptadecaenylamine ethyl imidazoline quaternary ammonium salt helps to improve the surface smoothness and glossiness of the paint film, making the paint film more beautiful. In addition, due to the addition of heptadecaenylamine ethyl imidazoline quaternary ammonium salt, the durability of the paint film is improved, and it can better resist the influence of temperature changes.

[0024] The weathering aid of the present invention is composed of zinc oxide and chromium oxide. Zinc oxide is an important thickener that can increase the viscosity and stability of the coating. Zinc oxide can enhance the weathering resistance of the coating; it can effectively resist ultraviolet radiation and moisture erosion, extend the service life of the coating, and can also make the coating surface smoother, flatter and brighter, improve the glossiness and stability of the metal surface, and make the paint surface look more beautiful. The role of chromium oxide in mercury paint is also mainly reflected in its antioxidant and protective properties. Adding chromium oxide to mercury paint can enhance the durability and stability of the paint film. Chromium oxide is a substance with high thermal stability and chemical inertness, which can form a dense protective film on the surface of the material, thereby effectively preventing the erosion of oxygen and other corrosive media. This protective film can significantly reduce the occurrence of oxidation reactions and improve the corrosion resistance of the material in a high temperature environment.

[0025] The dispersant used in the present invention has the functions of dispersing, emulsifying and wetting, can reduce surface tension, make mercury paint easier to spread and penetrate on the metal surface, effectively improve the dispersibility and emulsification of mercury paint, and enhance the overall performance and appearance of the paint film. The cosolvent used in the present invention helps to dissolve or disperse other components in the paint, thereby improving the fluidity and coating performance of the paint, thereby improving the overall quality and appearance of the paint film. The stabilizer hydroxyethyl cellulose ether of the present invention can significantly enhance the anti-precipitation performance of the coating, avoid the deposition of silver powder and filler, and will not cause flocculation, thereby improving the storage stability of mercury paint.

[0026] Beneficial Effects

[0027] The invention uses the synergistic effect of modified waterborne polyurethane resin, imidazoline derivatives, weathering additives and other components to improve the stability and weathering resistance of mercury paint while ensuring the metallic gloss and adhesion of the mercury paint; the waterborne system has a low VOC content and no irritating odor; the coating system has high gloss, strong adhesion, good weathering resistance and storage stability. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is further described below in conjunction with specific embodiments, but is not limited thereto.

[0029] Example 1

[0030] A water-based silver paint for building installation pipelines comprises the following raw materials: 40% of modified water-based polyurethane resin, 20% of silver powder, 3% of imidazoline derivatives, 3% of dispersant, 3% of cosolvent, 2% of weathering additive, 1% of stabilizer, and 100% of high-purity water.

[0031] The preparation steps of the modified waterborne polyurethane resin are:

[0032] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0033] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system cools to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA dimethylethanolamine is added to obtain a modified waterborne polyurethane resin solution.

[0034] The molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in step S2 is 1:5:0.5.

[0035] The modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0036] The dispersant is ethylene glycol; the cosolvent is ethylene glycol tert-butyl ether.

[0037] The imidazoline derivatives are heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:1.

[0038] The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0039] The stabilizer is hydroxyethyl cellulose ether.

[0040] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0041] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0042] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0043] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0044] Example 2

[0045] A water-based silver paint for building installation pipelines comprises the following raw materials: 45% of modified water-based polyurethane resin, 20% of silver powder, 4% of imidazoline derivatives, 5% of dispersant, 4% of cosolvent, 3% of weathering additive, 1% of stabilizer, and 100% of high-purity water.

[0046] The preparation steps of the modified waterborne polyurethane resin are:

[0047] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0048] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system is cooled to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA is added to obtain a modified waterborne polyurethane resin solution.

[0049] The molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in step S2 is 1:5:0.5.

[0050] The modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0051] The dispersant is ethylene oxide condensate; the cosolvent is ethylene glycol tert-butyl ether.

[0052] The imidazoline derivatives are heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:1.

[0053] The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0054] The stabilizer is hydroxyethyl cellulose ether.

[0055] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0056] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0057] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0058] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0059] Example 3

[0060] A water-based silver paint for building installation pipelines comprises the following raw materials: 45% of modified water-based polyurethane resin, 23% of silver powder, 5% of imidazoline derivatives, 5% of dispersant, 6% of cosolvent, 5% of weathering additive, 2% of stabilizer, and 100% of high-purity water.

[0061] The preparation steps of the modified waterborne polyurethane resin are:

[0062] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0063] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system is cooled to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA is added to obtain a modified waterborne polyurethane resin solution.

[0064] The molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in step S2 is 1:5:0.5.

[0065] The modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0066] The dispersant is isomeric alcohol polyoxyethylene ether; the cosolvent is dimethylformamide.

[0067] The imidazoline derivatives are heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:1.

[0068] The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0069] The stabilizer is hydroxyethyl cellulose ether.

[0070] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0071] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0072] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0073] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0074] Comparative Example 1

[0075] A water-based silver paint for building installation pipelines comprises the following raw materials: 45% of modified water-based polyurethane resin, 23% of silver powder, 5% of imidazoline derivatives, 5% of dispersant, 6% of cosolvent, 5% of weathering additive, 2% of stabilizer, and 100% of high-purity water.

[0076] The preparation steps of the modified waterborne polyurethane resin are:

[0077] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0078] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system is cooled to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA is added to obtain a modified waterborne polyurethane resin solution.

[0079] The molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in step S2 is 1:5:0.5.

[0080] The modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0081] The dispersant is isomeric alcohol polyoxyethylene ether; the cosolvent is dimethylformamide.

[0082] The imidazoline derivative is heptadecenylamineethyl imidazoline quaternary ammonium salt.

[0083] The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0084] The stabilizer is hydroxyethyl cellulose ether.

[0085] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0086] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0087] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0088] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0089] Compared with Example 3, the imidazoline derivative in this comparative example only uses heptadecanylamineethyl imidazoline quaternary ammonium salt, and the remaining steps and raw materials are the same as those in Example 3.

[0090] Comparative Example 2

[0091] A water-based silver powder paint for building installation pipelines comprises the following raw materials: 45% of modified water-based polyurethane resin, 23% of silver powder, 5% of dispersant, 6% of cosolvent, 5% of weathering additive, 2% of stabilizer, and 100% of high-purity water.

[0092] The preparation steps of the modified waterborne polyurethane resin are:

[0093] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0094] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system is cooled to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA is added to obtain a modified waterborne polyurethane resin solution.

[0095] The molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in step S2 is 1:5:0.5.

[0096] The modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0097] The dispersant is isomeric alcohol polyoxyethylene ether; the cosolvent is dimethylformamide.

[0098] The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0099] The stabilizer is hydroxyethyl cellulose ether.

[0100] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0101] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0102] Mixture B: Add high-purity water into a container, add weathering agent under stirring speed of 100-150r / min, continue stirring for 2-3min, then add dispersant and stir for 2-3min to obtain mixture B;

[0103] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0104] Compared with Example 3, this comparative example does not add imidazoline derivatives, and the remaining steps and raw materials are the same as those in Example 3.

[0105] Comparative Example 3

[0106] A water-based silver paint for building installation pipelines comprises the following raw materials: 45% of modified water-based polyurethane resin, 23% of silver powder, 5% of imidazoline derivatives, 5% of dispersant, 6% of cosolvent, 5% of weathering additive, 2% of stabilizer, and 100% of high-purity water.

[0107] The preparation steps of the modified waterborne polyurethane resin are:

[0108] S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110°C for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide;

[0109] S2: IPDI isophorone diisocyanate, PTMG polybutylene glycol, and DMPA dihydroxymethyl propionic acid are added to a flask, the temperature is raised to 90°C and the reaction is carried out under nitrogen protection for 2 hours. When the reaction system is cooled to 50°C, BDO1,4-butanediol is added and the reaction is continued at 70°C to obtain a top polymer containing an active group NCO capping. After the system is cooled to room temperature, the reaction product is poured into an emulsification barrel, a modified titanium dioxide solution is added, and then a neutralizing agent DMEA is added to obtain a modified waterborne polyurethane resin solution.

[0110] The molar ratio of the added amounts of IPDI, PTMG, DMPA and BDO in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, the modified titanium dioxide solution and the neutralizing agent DMEA in step S2 is 1:5:0.5.

[0111] The modified titanium dioxide solution in step S2 is composed of sodium dodecyl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:5.

[0112] The dispersant is isomeric alcohol polyoxyethylene ether; the cosolvent is dimethylformamide.

[0113] The imidazoline derivatives are heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:1.

[0114] The weathering agent is zinc oxide.

[0115] The stabilizer is hydroxyethyl cellulose ether.

[0116] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0117] Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0118] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0119] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0120] Compared with Example 3, in this comparative example, only zinc oxide is used as the weathering agent, and the other raw materials and steps are the same as those in Example 3.

[0121] Comparative Example 4

[0122] A water-based silver paint for building installation pipelines comprises the following raw materials: 45% of water-based polyurethane resin, 23% of silver powder, 5% of imidazoline derivatives, 5% of dispersant, 6% of cosolvent, 5% of weathering additive, 2% of stabilizer, and 100% of high-purity water.

[0123] The dispersant is isomeric alcohol polyoxyethylene ether; the cosolvent is dimethylformamide.

[0124] The imidazoline derivatives are heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:1.

[0125] The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:1.

[0126] The stabilizer is hydroxyethyl cellulose ether.

[0127] A method for preparing water-based silver paint for building installation pipelines, comprising the following steps:

[0128] Mixture A: put the aqueous polyurethane resin solution into a container, stir at 200 r / min, then add the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A;

[0129] Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B;

[0130] Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

[0131] Compared with Example 3, the waterborne polyurethane resin in this comparative example is not modified, and the remaining raw materials and steps are the same as those in Example 3.

[0132] Comparative Example 5

[0133] This comparative example uses commercially available finished waterborne polyurethane silver paint and its supporting additives.

[0134] Performance Testing

[0135] The water-based polyurethane silver powder paints described in Examples 1-3 and Comparative Examples 1-5 were respectively prepared according to the construction ratio, and then coated on the zinc phosphating treated steel plate, with a spray film thickness of 35-45 μm, flash dried for 15-20 minutes, and baked at 60-80°C for 1-2 hours. Then, the paint film was placed at room temperature for 7 days, and after drying, the paint film was tested for its gloss, weather resistance, adhesion and storage stability. The test results are shown in Table 1.

[0136] Performance test methods:

[0137] (1) Adhesion test: Assemble and adjust the test equipment according to the GB / T9286-2021 standard. Fix the cross-cut tester on a horizontal plane, scratch the surface of the coating with a diamond scratching tip, then fill the powder above the scratch with chalk, compact it with a glass sheet, and finally evaluate it. Evaluate the hardness and adhesion of the coating surface based on indicators such as the length and width of the scratch. The smaller the scratch, the better the hardness and adhesion of the coating.

[0138] (2) Gloss test: The gloss meter was measured according to GB / T9754-2007 standard, using BYKAG-4446 model. The gloss was measured 6 times at different parts of the paint film, and then the average value was calculated.

[0139] (3) Weather resistance: The accelerated test for resistance to artificial weathering shall be carried out in accordance with the provisions of "Exposure Cycle Type 7" in Appendix C of GB / T14522-2008. The comprehensive aging performance grade of the coating film shall be evaluated according to the decorative evaluation in GB / T1766;

[0140] (4) Storage stability test: According to GB / T6753.3-1986, take out representative samples and put them into three containers specified in the standard. The sample volume should be about 15 mm from the top of the container. Store in a constant temperature drying oven. When opening the lid, pay attention to whether the container is under pressure or vacuum. After opening the container, check whether the container is crusted, corroded, and has a corrupt smell, foul odor or sour smell.

[0141] Table 1

[0142]

[0143] As can be seen from Table 1, the water-based silver powder paints of Examples 1-3 of the present invention have good adhesion, high gloss, and better weather resistance than the finished water-based polyurethane silver powder paint (Comparative Example 5) sold in this city, and have good storage stability. There is no change after storage at 48°C for 30 days, and there is no coarsening phenomenon.

[0144] It should be noted that the above embodiments are only partial embodiments of the preferred methods of implementing the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

Claims

1. A water-based silver paint for building installation pipelines, characterized in that: The invention comprises the following raw materials: 40-45% of modified waterborne polyurethane resin, 20-23% of silver powder, 3-5% of imidazoline derivatives, 3-5% of dispersant, 3-6% of cosolvent, 2-5% of weathering agent, 1-2% of stabilizer and 100% of high-purity water.

2. The water-based silver paint for building installation pipelines according to claim 1 is characterized in that: The preparation steps of the modified waterborne polyurethane resin are: S1: Disperse 1g of nano-titanium dioxide in 40g of xylene, ultrasonically disperse for 30min, stir vigorously in a three-necked flask, add 0.6g of silane coupling agent KH550 and 40ml of deionized water, reflux at 110℃ for 4h, and after the reaction is completed, filter, wash and extract three times with anhydrous ethanol, and dry in a vacuum drying oven for 24h to obtain modified nano-titanium dioxide; S2: Add isophorone diisocyanate, polybutylene glycol and dihydroxymethyl propionic acid into a flask, heat to 90°C and react for 2 hours under nitrogen protection. When the reaction system is cooled to 50°C, add 1,4-butanediol and continue to react at 70°C to obtain a top polymer containing an active group NCO end-capped. After the system cools to room temperature, pour the reaction product into an emulsification barrel, add modified titanium dioxide solution, and then add neutralizer DMEA dimethylethanolamine to obtain a modified waterborne polyurethane resin solution.

3. The water-based silver paint for building installation pipelines according to claim 2 is characterized in that: The molar ratio of the added amounts of isophorone diisocyanate, polybutylene glycol, dihydroxymethyl propionic acid and 1,4-butanediol in step S2 is 1:0.2:0.2:0.5; the volume ratio of the reaction product, modified titanium dioxide solution and neutralizer in step S2 is 1:5:0.

5.

4. The water-based silver paint for building installation pipelines according to claim 2 is characterized in that: The modified titanium dioxide solution in step S2 is composed of sodium lauryl sulfate, the modified nano titanium dioxide in step S1, and deionized water, and the volume ratio of the three is 0.1:1:

5.

5. The water-based silver paint for building installation pipelines according to claim 1 is characterized in that: The dispersant is one or more of isomeric alcohol polyoxyethylene ether, polyoxyethylene glycol alkyl ester, alkylphenol polyethylene ether, polyoxyethylene alkyl ether, and condensate of ethylene glycol and ethylene oxide.

6. The water-based silver paint for building installation pipelines according to claim 1, characterized in that: The co-solvent is one or more of ethylene glycol tert-butyl ether, dimethylformamide, ethylene glycol tert-butyl ether, and polyol ester.

7. The water-based silver paint for building installation pipelines according to claim 1 is characterized in that: The imidazoline derivatives are heptadecanylamineethyl imidazoline quaternary ammonium salt and lauryl hydroxyethyl imidazoline in a mass ratio of 3:

1.

8. The water-based silver paint for building installation pipelines according to claim 1 is characterized in that: The weathering additives are zinc oxide and chromium oxide, and the mass ratio of the two is 2:

1.

9. The water-based silver paint for building installation pipelines according to claim 1, characterized in that: The stabilizer is hydroxyethyl cellulose ether.

10. A method for preparing the water-based silver paint for building installation pipelines according to any one of claims 1 to 8, characterized in that: Prepared by the following steps: Mixture A: put the modified waterborne polyurethane resin solution into a container, stir at 200 r / min, then put in the silver powder and continue stirring for 5-10 minutes, mix thoroughly, and obtain mixture A; Mixture B: Add high-purity water into a container, add a weathering agent under a stirring speed of 100-150 r / min, continue stirring for 2-3 minutes, then add a dispersant and stir for 2-3 minutes, add an imidazoline derivative and stir for 2-3 minutes to obtain a mixture B; Add mixture A to the paint mixing container, stir at a stirring speed of 200-300r / min for 3 minutes, then slowly add mixture B, continue stirring for 10-20 minutes, then slowly add the cosolvent and stabilizer to the paint mixing container, continue stirring for 3-5 minutes, and obtain the finished water-based silver powder paint after filtering.

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