High-hardness corrosion-resistant decorative aluminum profile and preparation method thereof

Abstract

The present application relates to the technical field of aluminum profile, and particularly relates to high-hardness corrosion-resistant decorative aluminum profile and a preparation method thereof. The present application obtains cellulose filler by adding microcrystalline cellulose, sulfuric acid solution and tetraethyl orthosilicate as main raw materials; then obtains modified cellulose filler by taking the cellulose filler and (3-mercaptopropyl) trimethoxysilane as main raw materials. Then, acrylic ester emulsion is obtained by adding deionized water, composite emulsifier, reaction monomer, buffer and ammonium persulfate; then, water-based acrylic resin paint is obtained by mixing acrylic ester emulsion, modified cellulose filler, photoinitiator, stabilizer and crosslinking coagent. The water-based acrylic resin paint is coated on the surface of the aluminum profile, and then dried, ultraviolet irradiated, washed and dried to obtain the finished product. The finished product prepared by the present application has good hardness and corrosion resistance, and therefore has wide application prospect in the technical field of aluminum profile.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum profiles, and particularly relates to a high-hardness corrosion-resistant decorative aluminum profile and a preparation method thereof. BACKGROUND

[0002] Aluminum profiles are a kind of lightweight, high-strength and corrosion-resistant materials, which have wide application value and modern significance. First of all, aluminum profiles have important value in modern engineering. Due to their lightweight and high-strength characteristics, aluminum profiles are widely used in manufacturing fields such as aerospace, automobile manufacturing, construction and decoration, electronic equipment, etc. Their excellent physical and chemical properties enable aluminum profiles to meet the needs of weight reduction, energy saving and environmental protection, and design diversification in different industries. Secondly, aluminum profiles also have excellent thermal and electrical conductivity. The high thermal conductivity of aluminum enables it to quickly conduct and dissipate heat, making it an ideal material for manufacturing heat sinks and heat exchangers. At the same time, the good electrical conductivity of aluminum profiles also enables them to be widely used in the electronic field, such as wires and cables, battery casings, etc.

[0003] However, there are still some pain points and challenges in the current aluminum profile technology that need to be overcome. On the one hand, the strength and rigidity of aluminum profiles are relatively low. Although the strength of aluminum profiles is higher than that of ordinary steel, it still needs to be further improved compared with some special engineering requirements. In some application fields such as automobile manufacturing and aerospace, higher strength and rigidity are required to meet safety and performance requirements. Secondly, the performance of aluminum profiles in some corrosive environments is not satisfactory. Although aluminum has a dense oxide film, it is still prone to corrosion in some strong acids, strong bases and salt corrosion media. These corrosion phenomena may cause surface damage, pitting and shrinkage of aluminum profiles, ultimately affecting their performance and service life.

[0004] In order to overcome the defects of the prior art, the present application provides a high-hardness corrosion-resistant decorative aluminum profile and a preparation method thereof. SUMMARY

[0005] The purpose of the present application is to provide a high-hardness corrosion-resistant decorative aluminum profile and a preparation method thereof to solve the problems in the prior art.

[0006] In order to solve the above technical problems, the present application provides the following technical solutions:

[0007] A preparation method of a high-hardness corrosion-resistant decorative aluminum profile, comprising the following steps:

[0008] Step one: dissolve the nanocrystalline cellulose powder in ethanol, then add tetraethyl orthosilicate and deionized water, react at 70-80℃ for 4-6h, slowly drop ammonia water in the reaction to adjust the pH to 10.5-11.5, after the reaction is completed, the product is aged, dialyzed to neutral pH, and freeze-dried to prepare the cellulose filler;

[0009] Step two: vacuum dry the cellulose filler at 100-110℃ for 3-5h, then mix the dried cellulose filler with toluene, ultrasonic for 60-80min, then add formic acid, anhydrous ethanol, deionized water and (3-mercaptopropyl) trimethoxysilane, 110-130℃ oil bath stirring reaction for 6-8h, after the reaction is completed, the solid product is centrifuged, washed and dried to prepare the modified cellulose filler;

[0010] Step three: mix 7 / 10 deionized water and composite emulsifier, stir at 30-40℃ for 15-25min to get the emulsifier solution, then add the reaction monomer to the emulsifier solution, stir for 40-60min to get the pre-emulsion; Mix 3 / 10 deionized water, buffer and 1 / 2 pre-emulsion, continue to heat to 80-90℃, then add 1 / 2 ammonium persulfate, continue to react for 40-60min to get the seed emulsion; Then add 1 / 2 remaining pre-emulsion and 1 / 2 ammonium persulfate, continue to react at 85-95℃ for 30-40min, after the reaction is completed, adjust the pH to 8.0-8.5 with ammonia water, then cool, filter and rinse to prepare the acrylate emulsion;

[0011] Step four: mix the acrylate emulsion, modified cellulose filler, photoinitiator, stabilizer and crosslinking aid to prepare the water-based acrylic resin coating; Apply the water-based acrylic resin coating to the surface of the aluminum profile, then irradiate under ultraviolet light for 500-550s, dry at 60-80℃ to get the finished product.

[0012] More preferably, in step one, the content of each component of the cellulose filler is: 1-2 parts of nanocrystalline cellulose powder, 80-100 parts of ethanol, 7-10 parts of tetraethyl orthosilicate, and 5-7 parts of deionized water.

[0013] More preferably, the preparation method of nanocrystalline cellulose powder is: mix microcrystalline cellulose and sulfuric acid solution, stir at 55-65℃ for 90-120min, after the reaction is completed, dilute and centrifugal wash the product to pH 5.0-5.5, then dialyze to neutral pH, and finally freeze-dry to get the nanocrystalline cellulose powder.

[0014] More preferably, the mass ratio of microcrystalline cellulose and sulfuric acid solution is 1:(30-35), and the mass concentration of sulfuric acid solution is 65-70%.

[0015] More preferably, in step two, the modified cellulose filler contains, by mass fraction, 8-10 parts of cellulose filler, 90-100 parts of toluene, 2-4 parts of formic acid, 5-7 parts of anhydrous ethanol, 8-10 parts of deionized water and 40-45 parts of (3-mercaptopropyl) trimethoxysilane.

[0016] More preferably, in step three, the acrylate emulsion contains, by mass fraction, 100-120 parts of deionized water, 3-5 parts of a composite emulsifier, 100-120 parts of a reaction monomer, 0.3-0.5 parts of a buffer, and 50-70 parts of ammonium persulfate.

[0017] More preferably, the reaction monomer is a mixture of n-butyl acrylate, N-hydroxyethyl acrylamide, pentaerythritol triacrylate, trimethoxy(4-vinylphenyl)silane, 3-acryloyloxypropyl trimethoxysilane and vinyl-terminated polysiloxane, with a mass ratio of 1:1:2:2:2:(4-6).

[0018] More preferably, the composite emulsifier is a mixture of sodium dodecyl sulfate and alkylphenol polyoxyethylene ether, with a mass ratio of 1:(1-2); and the buffer is sodium bicarbonate.

[0019] More preferably, in step four, the water-based acrylic resin coating contains, by mass fraction, 150-180 parts of the acrylate emulsion, 30-40 parts of the modified cellulose filler, 8-10 parts of a photoinitiator, 2-3 parts of a stabilizer and 2-3 parts of a crosslinking aid.

[0020] More preferably, the photoinitiator is 2-hydroxy-2-methylpropiophenone, the stabilizer is hydroquinone, and the crosslinking aid is cyanopentadiene bis ester; and the finished coating has a thickness of 15-20 microns.

[0021] The beneficial effects of the present application are as follows:

[0022] The present application adds microcrystalline cellulose, sulfuric acid solution and tetraethyl orthosilicate as main raw materials to prepare cellulose filler; then uses cellulose filler and (3-mercaptopropyl) trimethoxysilane as main raw materials to prepare modified cellulose filler. Then adds deionized water, composite emulsifier, reaction monomer, buffer, ammonium persulfate and ammonia to prepare acrylate emulsion; then adds acrylate emulsion, modified cellulose filler, photoinitiator, stabilizer and crosslinking aid to prepare water-based acrylic resin coating. The water-based acrylic resin coating is coated on the surface of aluminum profile, and then dried, ultraviolet irradiated, washed and dried to prepare the finished product.

[0023] The cellulose hybrid filler is prepared by adding microcrystalline cellulose, sulfuric acid solution, ethanol, tetraethyl orthosilicate and deionized water in step one. The cellulose hybrid filler added in the composite coating can increase the hardness of the resin coating and improve the impact resistance. Even under severe impact or extremely low temperature environment, the coating can maintain integrity and reliable protection. In step two, the cellulose hybrid filler is modified by adding a silane coupling agent (3-mercaptopropyl) trimethoxysilane containing mercapto to prepare a modified cellulose filler containing mercapto on the surface.

[0024] In step three, the acrylate emulsion is prepared by adding deionized water, composite emulsifier, reaction monomer, buffer, ammonium persulfate and ammonia. The reaction monomer is a mixture of n-butyl acrylate, N-hydroxyethyl acrylamide, pentaerythritol triacrylate, trimethoxy (4-vinylphenyl) silane, 3-acryloyloxypropyl trimethoxysilane and end-vinyl polysiloxane with a mass ratio of 1:1:2:2:2:(4-6). Trimethoxy (4-vinylphenyl) silane and 3-acryloyloxypropyl trimethoxysilane contain carbon-carbon double bonds and siloxane groups. End-vinyl polysiloxane contains carbon-carbon double bonds and a large number of siloxane groups. On the one hand, when the organic matter containing siloxane groups is added to the resin coating, the siloxane groups can be hydrolyzed and condensed to form structures such as coupling type, interpenetrating network type and cross-linked firm type between polymer molecules and between polymer and substrate, so that the coating layer has excellent corrosion resistance and weather resistance. On the other hand, the acrylate emulsion prepared by using the reaction monomer as the main raw material contains a large number of carbon-carbon double bonds. In step four, by adding a photoinitiator, the modified cellulose hybrid filler containing mercapto on the surface in step two can undergo thiol-ene click reaction with the acrylate emulsion. Through this reaction, the main resin and the resin filler can be effectively combined together to achieve full mixing. This process helps to improve the mechanical properties, interfacial bonding strength and overall performance of the material. DETAILED DESCRIPTION

[0025] The technical solutions in the present application will be described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0026] Raw material sources:

[0027] Microcrystalline cellulose, provided by Zhengzhou Best Food Additives Co., Ltd., particle size of 80 mesh; alkylphenol polyoxyethylene ether, provided by Jinan Xishuangyue Chemical Co., Ltd., model TX-10; aluminum profile, provided by Shanghai Xushen Aluminum Co., Ltd., model CS-8-2080W. The following parts are mass parts.

[0028] Example 1: Step one: 1 part of microcrystalline cellulose and 30 parts of 65% mass concentration sulfuric acid solution were mixed, and stirred at 65°C for 120 min. After the reaction was completed, the product was diluted and centrifugally washed until the pH was 5.5, then dialyzed until the pH was neutral, and finally freeze-dried to obtain nanocrystalline cellulose powder;

[0029] Step two: 1 part of nanocrystalline cellulose powder was dissolved in 80 parts of ethanol, then 7 parts of tetraethyl orthosilicate and 5 parts of deionized water were added, and the reaction was carried out at 80°C for 6 h, and ammonia water was slowly added during the reaction to adjust the pH to 11.5. After the reaction was completed, the product was aged, dialyzed to neutral pH, and freeze-dried to prepare a cellulose filler;

[0030] Step three: 8 parts of cellulose filler were vacuum dried at 110°C for 5 h, then the dried cellulose filler was mixed with 90 parts of toluene, ultrasonically treated for 80 min, then 2 parts of formic acid, 5 parts of anhydrous ethanol, 8 parts of deionized water and 40 parts of (3-mercapto propyl) trimethoxysilane were added, and the reaction was carried out at 130°C in an oil bath for 8 h. After the reaction was completed, the solid product was centrifuged, washed and dried to prepare a modified cellulose filler;

[0031] Step four: 1 part of n-butyl acrylate, 1 part of N-hydroxyethyl acrylamide, 2 parts of pentaerythritol triacrylate, 2 parts of trimethoxy(4-vinylphenyl)silane, 2 parts of 3-acryloyloxypropyl trimethoxysilane and 4 parts of vinyl-terminated polysiloxane were mixed to obtain a reaction monomer; 1 part of sodium dodecyl sulfate and 1 part of alkylphenol polyoxyethylene ether were mixed to obtain a composite emulsifier;

[0032] 70 parts of deionized water and 3 parts of composite emulsifier were mixed, stirred at 40°C for 25 min to obtain an emulsifier solution, then 100 parts of reaction monomer was added to the emulsifier solution, stirred for 60 min to obtain a pre-emulsion; 30 parts of deionized water, 0.3 parts of sodium bicarbonate and 1 / 2 of the pre-emulsion were mixed, continuously heated to 90°C, then 25 parts of ammonium persulfate was added, and the reaction was continued for 60 min to obtain a seed emulsion; 1 / 2 of the remaining pre-emulsion and 25 parts of ammonium persulfate were added, and the reaction was continued at 95°C for 40 min. After the reaction was completed, the pH was adjusted to 8.5 with ammonia water, and then cooled, filtered and rinsed to prepare an acrylate emulsion;

[0033] Step five: 150 parts of acrylate emulsion, 30 parts of modified cellulose filler, 8 parts of 2-hydroxy-2-methylpropiophenone, 2 parts of hydroquinone, 2 parts of cyano pentadiene double ester mixture, to prepare a water-based acrylic resin coating; the water-based acrylic resin coating is coated on the surface of the aluminum profile, and then irradiated under ultraviolet light for 550 s, dried at 80°C to obtain the finished product; the finished product coating thickness is 20 μm.

[0034] Example 2: Step one: mix 1 part of microcrystalline cellulose and 30 parts of 65% mass concentration sulfuric acid solution, stir at 60°C for 105 min, after the reaction is completed, dilute and centrifugal wash the product to pH 5.3, then dialysis to neutral pH, and finally freeze-drying to obtain nano microcrystalline cellulose powder;

[0035] Step two: dissolve 1 part of nano microcrystalline cellulose powder in 80 parts of ethanol, then add 7 parts of tetraethyl orthosilicate and 5 parts of deionized water, react at 75°C for 5h, and slowly add ammonia water in the reaction to adjust the pH to 11, after the reaction is completed, the product is aged, dialyzed to neutral pH, and freeze-dried to obtain a cellulose filler;

[0036] Step three: dry 8 parts of cellulose filler at 105°C under vacuum for 4h, then mix the dried cellulose filler with 90 parts of toluene, ultrasonic for 70 min, then add 2 parts of formic acid, 5 parts of anhydrous ethanol, 8 parts of deionized water and 40 parts of (3-mercapto propyl) trimethoxysilane, 120°C oil bath stirring reaction for 7h, after the reaction is completed, the solid product is centrifuged, washed and dried to obtain a modified cellulose filler;

[0037] Step four: mix 1 part of n-butyl acrylate, 1 part of N-hydroxyethyl acrylamide, 2 parts of pentaerythritol triacrylate, 2 parts of trimethoxy(4-vinylphenyl)silane, 2 parts of 3-acryloyloxypropyl trimethoxysilane and 4 parts of vinyl-terminated polysiloxane to obtain a reaction monomer; mix 1 part of sodium dodecyl sulfate and 1 part of alkylphenol polyoxyethylene ether to obtain a composite emulsifier;

[0038] Mix 70 parts of deionized water and 3 parts of composite emulsifier, stir at 35°C for 20 min to obtain an emulsifier solution, then add 100 parts of reaction monomer to the emulsifier solution, stir for 50 min to obtain a pre-emulsion; mix 30 parts of deionized water, 0.3 parts of sodium bicarbonate and 1 / 2 of the pre-emulsion, continuously heat to 85°C, then add 25 parts of ammonium persulfate, continue to react for 50 min to obtain a seed emulsion; then add 1 / 2 of the remaining pre-emulsion and 25 parts of ammonium persulfate, continue to react at 90°C for 35 min, after the reaction is completed, adjust the pH to 8.2 with ammonia water, then cool, filter, rinse to obtain an acrylate emulsion;

[0039] Step five: 150 parts of acrylate emulsion, 30 parts of modified cellulose filler, 8 parts of 2-hydroxy-2-methylpropiophenone, 2 parts of hydroquinone, 2 parts of cyano pentadiene double ester mixture, to prepare a water-based acrylic resin coating; the water-based acrylic resin coating is coated on the surface of the aluminum profile, and then irradiated under ultraviolet light for 525 s, dried at 70℃ to obtain the finished product; the finished product coating thickness is 20 μm.

[0040] Example 3: Step one: mix 1 part of microcrystalline cellulose and 30 parts of 65% mass concentration sulfuric acid solution, stir at 55℃ for 90 min, after the reaction is completed, dilute and centrifugal wash the product to pH 5.0, then dialysis to neutral pH, and finally freeze-drying to obtain nano microcrystalline cellulose powder;

[0041] Step two: dissolve 1 part of nano microcrystalline cellulose powder in 80 parts of ethanol, then add 7 parts of tetraethyl orthosilicate and 5 parts of deionized water, react at 70℃ for 4h, and slowly add ammonia water in the reaction to adjust the pH to 10.5, after the reaction is completed, the product is aged, dialyzed to neutral pH, and freeze-dried to obtain a cellulose filler;

[0042] Step three: dry 8 parts of cellulose filler at 100℃ under vacuum for 3h, then mix the dried cellulose filler with 90 parts of toluene, ultrasonic for 60 min, then add 2 parts of formic acid, 5 parts of anhydrous ethanol, 8 parts of deionized water and 40 parts of (3-mercapto propyl) trimethoxysilane, 110℃ oil bath stirring reaction for 6h, after the reaction is completed, centrifugal, washing and drying the solid product to obtain a modified cellulose filler;

[0043] Step four: mix 1 part of n-butyl acrylate, 1 part of N-hydroxyethyl acrylamide, 2 parts of pentaerythritol triacrylate, 2 parts of trimethoxy(4-vinylphenyl)silane, 2 parts of 3-acryloyloxypropyl trimethoxysilane and 4 parts of vinyl-terminated polysiloxane to obtain a reaction monomer; mix 1 part of sodium dodecyl sulfate and 1 part of alkylphenol polyoxyethylene ether to obtain a composite emulsifier;

[0044] Mix 70 parts of deionized water and 3 parts of composite emulsifier, stir at 30℃ for 15 min to obtain an emulsifier solution, then add 100 parts of reaction monomer to the emulsifier solution, stir for 40 min to obtain a pre-emulsion; mix 30 parts of deionized water, 0.3 parts of sodium bicarbonate and 1 / 2 of the pre-emulsion, continuously heat to 80℃, then add 25 parts of ammonium persulfate, continue to react for 40 min to obtain a seed emulsion; then add 1 / 2 of the remaining pre-emulsion and 25 parts of ammonium persulfate, continue to react at 85℃ for 30 min, after the reaction is completed, adjust the pH to 8.0 with ammonia water, then cool, filter, rinse to obtain an acrylate emulsion;

[0045] Step five: 150 parts of the acrylate emulsion, 30 parts of the modified cellulose filler, 8 parts of 2-hydroxy-2-methylpropiophenone, 2 parts of hydroquinone, and 2 parts of cyanopropylene double ester were mixed to prepare a water-based acrylic resin coating; the water-based acrylic resin coating was coated onto the surface of the aluminum profile, then irradiated under ultraviolet light for 500 s, and dried at 60°C to obtain a finished product; the finished product had a coating thickness of 20 μm.

[0046] Comparative Example 1: The preparation step of the modified cellulose filler was removed, and the remaining steps were the same as those of Example 1, and the specific steps were as follows:

[0047] Step one: 1 part of n-butyl acrylate, 1 part of N-hydroxyethyl acrylamide, 2 parts of pentaerythritol triacrylate, 2 parts of trimethoxy(4-vinylphenyl)silane, 2 parts of 3-acryloyloxypropyl trimethoxysilane, and 4 parts of terminal vinyl polysiloxane were mixed to obtain a reaction monomer; 1 part of sodium dodecyl sulfate and 1 part of alkylphenol polyoxyethylene ether were mixed to obtain a composite emulsifier;

[0048] 70 parts of deionized water and 3 parts of the composite emulsifier were mixed, stirred at 40°C for 25 min to obtain an emulsifier solution, and then 100 parts of the reaction monomer was added to the emulsifier solution and stirred for 60 min to obtain a pre-emulsion; 30 parts of deionized water, 0.3 parts of sodium bicarbonate, and 1 / 2 of the pre-emulsion were mixed, continuously heated to 90°C, and then 25 parts of ammonium persulfate was added and reacted for 60 min to obtain a seed emulsion; 1 / 2 of the remaining pre-emulsion and 25 parts of ammonium persulfate were added and reacted at 95°C for 40 min, and then the pH was adjusted to 8.5 with ammonia water after the reaction was completed, and then cooled, filtered, and rinsed to obtain an acrylate emulsion;

[0049] Step two: 150 parts of the acrylate emulsion, 8 parts of 2-hydroxy-2-methylpropiophenone, 2 parts of hydroquinone, and 2 parts of cyanopropylene double ester were mixed to prepare a water-based acrylic resin coating; the water-based acrylic resin coating was coated onto the surface of the aluminum profile, then irradiated under ultraviolet light for 550 s, and dried at 80°C to obtain a finished product; the finished product had a coating thickness of 20 μm.

[0050] Comparative Example 2: The terminal vinyl polysiloxane in the reaction monomer was removed, and the remaining steps were the same as those of Example 1, and the specific steps were as follows: Step one: 1 part of microcrystalline cellulose and 30 parts of a 65% mass concentration sulfuric acid solution were mixed and stirred at 65°C for 120 min, and then the product was diluted and centrifugally washed to a pH of 5.5, then dialyzed to a neutral pH, and finally freeze-dried to obtain a nano-microcrystalline cellulose powder;

[0051] Step two: 1 part of nanocrystalline cellulose powder was dissolved in 80 parts of ethanol, then 7 parts of tetraethyl orthosilicate and 5 parts of deionized water were added, and the reaction was carried out at 80℃ for 6h, and ammonia water was slowly added during the reaction to adjust the pH to 11.5. After the reaction was completed, the product was aged, dialyzed to neutral pH, freeze-dried to prepare a cellulose filler;

[0052] Step three: 8 parts of cellulose filler were vacuum dried at 110℃ for 5h, then the dried cellulose filler was mixed with 90 parts of toluene, ultrasonicated for 80min, then 2 parts of formic acid, 5 parts of anhydrous ethanol, 8 parts of deionized water and 40 parts of (3-mercapto propyl) trimethoxysilane were added, and the reaction was carried out at 130℃ oil bath stirring for 8h. After the reaction was completed, the solid product was centrifuged, washed and dried to prepare a modified cellulose filler;

[0053] Step four: 1 part of n-butyl acrylate, 1 part of N-hydroxyethyl acrylamide, 2 parts of pentaerythritol triacrylate, 2 parts of trimethoxy(4-vinylphenyl)silane and 2 parts of 3-acryloyloxypropyl trimethoxysilane were mixed to obtain a reaction monomer; 1 part of sodium dodecyl sulfate and 1 part of alkylphenol polyoxyethylene ether were mixed to obtain a composite emulsifier;

[0054] 70 parts of deionized water and 3 parts of composite emulsifier were mixed, stirred at 40℃ for 25min to obtain an emulsifier solution, then 100 parts of reaction monomer was added to the emulsifier solution, stirred for 60min to obtain a pre-emulsion; 30 parts of deionized water, 0.3 parts of sodium bicarbonate and 1 / 2 of the pre-emulsion were mixed, continuously heated to 90℃, then 25 parts of ammonium persulfate was added, and the reaction was continued for 60min to obtain a seed emulsion; then 1 / 2 of the remaining pre-emulsion and 25 parts of ammonium persulfate were added, and the reaction was continued at 95℃ for 40min. After the reaction was completed, the pH was adjusted to 8.5 with ammonia water, and then cooled, filtered and rinsed to prepare an acrylate emulsion;

[0055] Step five: 150 parts of acrylate emulsion, 30 parts of modified cellulose filler, 8 parts of 2-hydroxy-2-methylpropiophenone, 2 parts of hydroquinone, and 2 parts of cyanopropylene double ester were mixed to prepare a water-based acrylic resin coating; the water-based acrylic resin coating was coated onto the surface of the aluminum profile, then irradiated under ultraviolet light for 550s, and dried at 80℃ to obtain a finished product; the finished product has a coating thickness of 20μm.

[0056] Detection test:

[0057] Impact resistance test: according to GB / T 1732-1993 "Paint film impact resistance test method", a tin plate with a size of 50×120×0.3mm was used as a test plate, and the water-based acrylic resin coating prepared by the present application was sprayed onto the surface of the test plate to obtain a test sample after curing. The test sample was placed on an anvil, and a weight was placed on it to perform an impact test.

[0058] Corrosion resistance test: the prepared product of the application is used as a sample, the sample is immersed in 3.5wt% NaCI as electrolyte, and the electrochemical performance of the coating is characterized by using Shanghai Chenhua CHI660C electrochemical workstation, and then the corrosion rate is calculated according to the formula;

[0059] Hydrophobicity test: the prepared product of the application is used as a sample, the wetting angle measuring instrument is used to measure the contact angle of the liquid drop on the coating surface of the sample, the micro-syringe (1.0ml) is used to vertically drop the detection liquid on the coating surface about 3mm, the rotation knob is rotated, the deionized water drop is slowly dropped, the contact angle image is photographed within 3-10s, and the contact angle is measured by five-point method. The average value of the contact angles of five points on different parts of the coating is taken as the contact angle of the sample. The results are as follows:

[0060] Cracking resistance / (kg-cm) Corrosion rate / (mm / y) Water contact angle / ° Example 1 115 9.7 x 10 -4 ]]> 115 Example 2 114 9.6 x 10 -4 ]]> 114 Example 3 113 9.5 x 10 -4 ]] 113 Comparative Example 1 93 11.7 x 10 -4 ]] 108 Comparative Example 2 108 13.3 x 10 -4 ]] 103

[0061] Conclusion: the amount of examples 1-3 is unchanged, only the reaction parameters are modified. According to the experimental data, the performance of the sample does not change significantly. Comparative example 1: the preparation steps of the modified cellulose filler are removed, and the rest is the same as example 1. According to the experimental data, compared with example 1, the anti-cracking property is reduced to 93kg·cm, the corrosion rate is increased to 11.7×10 -4 mm / y, and the water contact angle is 108°. The analysis reason is that the cellulose hybrid filler is an excellent reinforcing filler with high strength and good stability, so the mechanical properties of the water-based acrylic resin coating will be reduced after removing it, so the corrosion rate increases and the anti-cracking property decreases.

[0062] Comparative example 2: the terminal vinyl polysiloxane in the reaction monomer is removed, and the rest is the same as example 1. According to the experimental data, compared with example 1, the anti-cracking property is reduced to 108kg·cm, the corrosion rate is increased to 13.3×10 -4 mm / y, and the water contact angle is reduced to 103°. The analysis reason is that the reaction monomer of the application contains a large amount of siloxane group, and the siloxane group can hydrolyze and condense to form coupling type, interpenetrating network type and cross-linked firm type structures between polymer molecules and between polymer and substrate, so that the coating has excellent corrosion resistance. Therefore, adjusting and reducing the amount of siloxane will significantly reduce the corrosion resistance and hydrophobicity of the sample.

[0063] It is to be noted that, in the present text, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0064] Finally, it should be noted that the above-mentioned only constitutes preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications, equivalent substitutions, improvements and the like of the technical solutions described in the foregoing embodiments can still be made. Any modifications, equivalent substitutions, improvements and the like made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for producing a high-hardness corrosion-resistant decorative aluminum material, characterized by comprising: Comprise the following steps: ​ Step one: the nanocrystalline cellulose powder is dissolved in ethanol, then tetraethyl orthosilicate and deionized water are added, and the reaction is carried out at 70-80 DEG C for 4-6h, and ammonia water is slowly added dropwise during the reaction to adjust the pH to 10.5-11.5, after the reaction is completed, the product is aged, dialyzed to neutral pH, and freeze-dried to prepare a cellulose filler; Step two: the cellulose filler is vacuum dried at 100-110 DEG C for 3-5h, then the dried cellulose filler and toluene are mixed, ultrasonic is applied for 60-80min, then formic acid, anhydrous ethanol, deionized water and (3-mercaptopropyl) trimethoxysilane are added, and the reaction is carried out at 110-130 DEG C oil bath stirring for 6-8h, after the reaction is completed, the solid product is centrifuged, washed and dried to prepare a modified cellulose filler; Step three: 7 / 10 deionized water and a composite emulsifier are mixed, stirred at 30-40 DEG C for 15-25min to obtain an emulsifier solution, then the reaction monomer is added to the emulsifier solution, and stirred for 40-60min to obtain a pre-emulsion; 3 / 10 deionized water, a buffer and 1 / 2 pre-emulsion are mixed, continuously heated to 80-90 DEG C, then 1 / 2 ammonium persulfate is added, and the reaction is continued for 40-60min to obtain a seed emulsion; 1 / 2 remaining pre-emulsion and 1 / 2 ammonium persulfate are added, and the reaction is continued at 85-95 DEG C for 30-40min, after the reaction is completed, the pH is adjusted to 8.0-8.5 with ammonia water, then cooled, filtered and rinsed to prepare an acrylate emulsion; the reaction monomer is a mixture of n-butyl acrylate, N-hydroxyethyl acrylamide, pentaerythritol triacrylate, trimethoxy(4-vinylphenyl)silane, 3-acryloyloxypropyltrimethoxysilane and end-vinyl polysiloxane, and the mass ratio is 1:1:2:2:2: (4-6); Step four: the acrylate emulsion, modified cellulose filler, photoinitiator, stabilizer and crosslinking aid are mixed to prepare a water-based acrylic resin coating; the water-based acrylic resin coating is coated onto the surface of the aluminum profile, then irradiated under ultraviolet light for 500-550s, and dried at 60-80 DEG C to obtain a finished product.

2. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 1, characterized in that: In step one, the content of each component of the cellulose filler is as follows: 1-2 parts of nanocrystalline cellulose powder, 80-100 parts of ethanol, 7-10 parts of tetraethyl orthosilicate and 5-7 parts of deionized water.

3. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 2, characterized in that: The preparation method of the nanocrystalline cellulose powder is as follows: microcrystalline cellulose and sulfuric acid solution are mixed, and the reaction is carried out at 55-65 DEG C for 90-120min, after the reaction is completed, the product is diluted and centrifugally washed until the pH is 5.0-5.5, then dialyzed until the pH is neutral, and finally freeze-dried to obtain the nanocrystalline cellulose powder.

4. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 3, characterized in that: The mass ratio of the microcrystalline cellulose and the sulfuric acid solution is 1:(30-35), and the mass concentration of the sulfuric acid solution is 65-70%.

5. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 1, characterized in that: In step two, the content of each component of the modified cellulose filler is as follows: 8-10 parts of cellulose filler, 90-100 parts of toluene, 2-4 parts of formic acid, 5-7 parts of anhydrous ethanol, 8-10 parts of deionized water and 40-45 parts of (3-mercaptopropyl) trimethoxysilane.

6. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 1, characterized in that: In step three, the content of each component of the acrylate emulsion is as follows: 100-120 parts of deionized water, 3-5 parts of composite emulsifier, 100-120 parts of reaction monomer, 0.3-0.5 parts of buffer, and 50-70 parts of ammonium persulfate.

7. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 6, characterized in that: The composite emulsifier is a mixture of sodium dodecyl sulfate and alkylphenol polyoxyethylene ether, with a mass ratio of 1:(1-2); the buffer is sodium bicarbonate.

8. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 1, characterized in that: In step four, the content of each component of the water-based acrylic resin coating is as follows: 150-180 parts of acrylate emulsion, 30-40 parts of modified cellulose filler, 8-10 parts of photoinitiator, 2-3 parts of stabilizer, and 2-3 parts of crosslinking aid.

9. The method for preparing a high-hardness, corrosion-resistant decorative aluminum profile according to claim 8, characterized in that: The photoinitiator is 2-hydroxy-2-methylpropiophenone, the stabilizer is hydroquinone, and the crosslinking aid is cyanopentadiene bis ester; the thickness of the finished coating is 15-20 μm.