Corrosion-resistant industrial aluminum profile and method for manufacturing the same

Abstract

The application discloses a kind of corrosion-resistant industrial aluminum profile and manufacturing method thereof, belong to aluminum profile preparation technical field.In the surface of aluminum profile, corrosion-resistant paint is electrostatically sprayed, paint is with epoxy resin as matrix, it is separated from aluminum profile and outside environment, improve the corrosion resistance and water resistance of aluminum profile;The compatibility of prepared nanometer silicon dioxide with epoxy resin matrix is better than that of ordinary nanometer silicon dioxide, can improve the wear resistance of paint, also can promote the curing of paint;Prepared auxiliary can significantly enhance the heat resistance, corrosion resistance, light aging resistance and certain degree of water resistance of paint, and long-term stable performance;Therefore, the aluminum profile prepared by the application has excellent corrosion resistance and water resistance, and the paint sprayed on the surface of the aluminum profile has good wear resistance, also has stable and efficient corrosion resistance, heat resistance and light aging resistance, and has important application value in the field of aluminum profile preparation technology.

Description

Technical Field

[0001] This invention belongs to the field of aluminum profile preparation technology, specifically, it relates to a corrosion-resistant industrial aluminum profile and its manufacturing method. Background Technology

[0002] With energy resources becoming increasingly depleted and the environment deteriorating, governments worldwide are placing higher demands on energy conservation and emission reduction, leading to greater emphasis on the new energy sector. Among new energy sources, solar energy stands out as a green, pollution-free, and inexhaustible energy source. Compared to other energy sources, solar energy is ubiquitous on Earth, readily available locally. Its utilization primarily involves using photovoltaic (PV) equipment to directly convert sunlight into electricity through the PV effect.

[0003] Common photovoltaic equipment, especially solar panel frames, photovoltaic brackets, and photovoltaic blocks, mostly uses industrial aluminum profiles. Industrial aluminum profiles are an alloy material with aluminum as the main component, produced by hot melting and extrusion processes to form aluminum materials with different cross-sectional shapes. They possess many excellent properties, including lightweight, high strength, good plasticity and processing performance, ease of processing, aesthetics, non-magnetic, non-toxic, sound absorption, and low-temperature resistance. However, despite their superior performance, industrial aluminum profiles have relatively low corrosion resistance. Air contains gases such as CO2, SO2, and H2S. When these pollutants encounter water vapor in the air, they produce a slightly acidic substance that corrodes the aluminum profile, causing it to gradually lose its performance and significantly shortening its service life, severely limiting its application.

[0004] Currently, a common method to improve the corrosion resistance of industrial aluminum profiles is to spray coatings onto their surfaces, isolating them from the external environment and thus protecting them. However, existing corrosion-resistant protective coatings applied to aluminum profiles are prone to peeling and flaking under outdoor sun and rain, exhibit poor UV resistance, and suffer significant performance degradation in high summer temperatures, rendering them ineffective as protective coatings and unsuitable for outdoor working conditions. Therefore, it is urgent to solve these problems to meet the higher demands of the aluminum profile manufacturing technology field. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a corrosion-resistant industrial aluminum profile and its manufacturing method.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for manufacturing corrosion-resistant industrial aluminum profiles includes the following steps:

[0008] A1. After wiping the surface of the aluminum profile with acetone, immerse it in a hexadecyltrimethylammonium bromide aqueous solution (2% by mass) to degrease the surface and obtain a degreased aluminum profile.

[0009] A2. Spray micro-etching solution onto the surface of the degreased aluminum profile, clean it, dry it, and then put it into an oxidation tank for anodizing. After oxidation, wash it with water and dry it to obtain the pretreated aluminum profile.

[0010] A3. Electrostatic spraying is applied to the surface of the pretreated aluminum profile to apply a corrosion-resistant coating. After spraying, the profile is placed in a curing chamber for curing. Once curing is complete, the profile is allowed to cool naturally to room temperature to obtain a corrosion-resistant industrial aluminum profile.

[0011] Furthermore, in step A2, the micro-etching solution is prepared by mixing hydrochloric acid, phosphoric acid, triethanolamine, diammonium hydrogen phosphate and water in a mass ratio of 1:1-4:1-3:2-4:30-40.

[0012] Furthermore, in step A3, during electrostatic spraying, the compressed air pressure is 0.5-0.7 MPa, the electrostatic spraying voltage is 40-60 KV, and the distance between the spray gun and the workpiece is 150-200 mm.

[0013] Furthermore, in step A3, the curing temperature is 200-220℃ and the curing time is 1-2 hours.

[0014] By degreasing and micro-etching the surface of aluminum profiles, the oxide film on the surface can be removed, and a microporous structure can be formed on the surface of the aluminum profiles to facilitate the adhesion of the sprayed coating during subsequent spraying. Then, anodizing produces a more uniform oxide film, which improves the corrosion resistance of the aluminum profile substrate. Finally, by using electrostatic spraying, a smooth and uniform coating can be obtained, and the utilization rate of the coating is high, saving costs.

[0015] Furthermore, the corrosion-resistant coating is prepared through the following steps:

[0016] B1. In a three-necked flask equipped with a stirring and reflux device, bisphenol epoxy resin (epoxy value 0.54), ethylene glycol diglycidyl ether and additives are mixed, and then 2-ethyl-4-methylimidazolium (catalyst) is added. After stirring and mixing, nitrogen gas is introduced, the reaction temperature is controlled at 140℃, and the reaction is refluxed for 5 hours to obtain modified epoxy resin.

[0017] B2. The modified epoxy resin, film-forming aid, curing accelerator, and modified nano-silica obtained in step B1 are placed in a ball mill and dry-mixed for 10-15 hours. The mixture is then passed through a 150-200 mesh sieve to obtain a corrosion-resistant coating.

[0018] Further, the raw materials are as follows by weight: 60-80 parts bisphenol epoxy resin, 5-10 parts ethylene glycol diglycidyl ether, 5-15 parts additives, 2-4 parts 2-ethyl-4-methylimidazole, 1-3 parts film-forming aid, 0.5-1 part curing accelerator, and 8-16 parts modified nano silica.

[0019] Furthermore, the film-forming aid is one of dodecyl carbonate, ethylene glycol monobutyl ether, and polyethylene glycol octylphenyl ether.

[0020] Furthermore, the curing accelerator is one of 2-methylimidazole and 3-methylimidazole.

[0021] The resulting coating uses epoxy resin as a matrix, giving it excellent corrosion resistance and water resistance. The curing accelerator can work synergistically with the modified nano-silica to jointly promote the curing of the epoxy resin.

[0022] Furthermore, the modified nano-silica is prepared through the following steps:

[0023] Nano-silica was mixed with an ethanol aqueous solution and added to a magnetic stirring device. A magnet was added, and the stirring was started. The mixture was dispersed for 15 minutes to ensure that the nano-silica was evenly dispersed in the ethanol aqueous solution. The device was then evacuated and N2 gas was introduced. γ-aminopropyltriethoxysilane (silane coupling agent KH-550) was added, and oil bath heating was started at 50°C. The cooling water was turned on, and the reaction was carried out at 80°C for 4 hours. The mixture was then filtered, washed with ethanol, and dried in a vacuum drying oven for 2 hours to obtain modified nano-silica.

[0024] Furthermore, the ratio of the amount of nano-silica, aqueous ethanol solution, and γ-aminopropyltriethoxysilane is 1.0g:100mL:4.5g.

[0025] Nano silica has many -OH groups on its surface. When reacted with KH-550, -NH2 active groups can be introduced to obtain modified nano silica. Compared with ordinary nano silica, it has better compatibility with epoxy resin matrix and is easier to disperse. It can not only improve the wear resistance of coatings, but also act as a curing agent to promote the curing of coatings.

[0026] Furthermore, the additive is prepared by the following steps:

[0027] S1. At room temperature, add viscous acid, DAST (diethylaminotrifluoride, fluorinating agent) and dichloromethane to a flask and stir until homogeneous. React for 55 min, filter, take the filter cake, wash 3-4 times with anhydrous ethanol, and dry to obtain intermediate 1; the ratio of viscous acid, DAST and dichloromethane is 20.9 g: 10.2 g: 100 mL.

[0028] Under the action of a fluorinating reagent, the hydroxyl groups on the viscous acid are converted into monofluorinated compounds. The fluorinating reagent is selective, and the carboxyl group is unaffected, yielding intermediate 1. The specific reaction process is shown below:

[0029]

[0030] S2. In a three-necked flask equipped with a stirring reflux device, intermediate 1, pentamethylpiperidinol, and N,N-dimethylformamide (DMF) were mixed and stirred until homogeneous. Dicyclohexylcarbodiimide (DCC, dehydrating agent) and 4-dimethylaminopyridine (DMAP, catalyst) were added sequentially. The reaction temperature was controlled at 80℃, and the reaction was carried out for 8 hours. After the reaction was completed, the mixture was filtered, and some solvent was removed by rotary evaporation. The mixture was washed 2-3 times and dried under vacuum to obtain intermediate 2. The ratio of intermediate 1, pentamethylpiperidinol, N,N-dimethylformamide, dicyclohexylcarbodiimide, and 4-dimethylaminopyridine was 22.7g:17.1g:150mL:20.6g:0.2g.

[0031] Under the action of DCC and DMAP, intermediate 1 and pentamethylpiperidinol undergo an esterification reaction. By controlling the molar ratio of the two to be close to 1:1 and with intermediate 1 in slight excess, only one carboxyl group on intermediate 1 participates in the reaction, yielding intermediate 2. The specific reaction process is shown below:

[0032]

[0033] S3. In a three-necked flask equipped with a stirrer, intermediate 2, ethylenediamine, and N,N-dimethylformamide were mixed and stirred until homogeneous. Dicyclohexylcarbodiimide was added, and the apparatus was placed in a water bath and reacted at 50°C for 4 hours. After the reaction was completed, the mixture was filtered, and most of the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography (using a mixed solvent of ethyl acetate and petroleum ether in a volume ratio of 2:5). The eluent was removed by rotary evaporation to obtain intermediate 3. The ratio of intermediate 2, ethylenediamine, N,N-dimethylformamide, and dicyclohexylcarbodiimide was 37.1 g: 7.3 g: 150 mL: 20.6 g.

[0034] The carboxyl group on intermediate 2 undergoes an amidation reaction with the amino group on ethylenediamine. This reaction can occur under relatively mild conditions with the aid of dicyclohexylcarbodiimide. By controlling the molar ratio of the two to be close to 1:1 and with a slight excess of ethylenediamine, only one amino group on the ethylenediamine participates in the reaction, yielding intermediate 3. The specific reaction process is shown below:

[0035]

[0036] S4. In a three-necked flask equipped with a stirrer, terephthalic diisocyanate, intermediate 3, and dimethyl sulfoxide (DMSO) were mixed. Tributyltin (catalyst) was added and stirred until homogeneous. The temperature was gradually increased to 70°C and the mixture was kept at this temperature for 6 hours with continuous stirring. After the reaction was completed, the solvent was removed by vacuum distillation and the mixture was dried under vacuum to obtain the auxiliary agent. The ratio of terephthalic diisocyanate, intermediate 3, dimethyl sulfoxide, and tributyltin was 18.4 g: 41.3 g: 150 mL: 2 g.

[0037] The isocyanate group in terephthalic diisocyanate reacts with the amino group on intermediate 3 to form a urea group. By controlling the molar ratio of the two to be close to 1:1 and with a slight excess of terephthalic diisocyanate, only one isocyanate group on the terephthalic diisocyanate participates in the reaction, thus obtaining the auxiliary agent. The specific reaction process is shown below:

[0038]

[0039] The additive molecule prepared by this invention contains an isocyanate group at one end. This isocyanate group can react with the epoxy groups in the epoxy resin matrix under the action of a catalyst to generate a five-membered ring oxazolidinone structure. Oxazolidinone is a five-membered heterocycle; its introduction into the epoxy resin matrix can improve the strength and heat resistance of the epoxy resin matrix. Furthermore, the additive is chemically bonded to the epoxy resin matrix, enhancing the migration and exudation resistance of the small molecule and improving the stability of the additive. In addition, the additive also contains a CF bond and a hindered phenolic structure, wherein the CF bond has low polarity and possesses... The strong bond energy, with higher chemical bond energy resulting in better stability, further enhances the heat resistance and certain waterproof properties of the matrix. Furthermore, the fluorine atoms are tightly arranged around the carbon atoms, forming a C-C bond protective barrier, reducing the surface energy of the matrix and significantly enhancing its corrosion resistance. Finally, the introduced hindered amine decomposes hydrogen dioxide to generate stable nitric oxide radicals. This compound can very effectively capture free radicals generated during photo-oxidative degradation, effectively inhibiting the photo-oxidative degradation of the matrix. Under stable conditions, it can be regenerated, improving the epoxy resin matrix's resistance to photoaging.

[0040] The beneficial effects of this invention are:

[0041] 1. This invention, through degreasing and micro-etching of the aluminum profile surface, can form a microporous structure on the aluminum profile surface, which facilitates the improvement of the adhesion of the sprayed coating during subsequent spraying;

[0042] 2. Anodizing produces a more uniform oxide film, which improves the corrosion resistance of the aluminum profile substrate;

[0043] 3. Electrostatic spraying of corrosion-resistant coating on the surface of aluminum profiles. The coating uses epoxy resin as a base to isolate the aluminum profiles from the external environment, thereby improving the corrosion resistance and water resistance of the aluminum profiles.

[0044] 4. Compared with ordinary nano-silica, the prepared nano-silica has better compatibility with epoxy resin matrix, which can improve the wear resistance of coating and promote the curing of coating.

[0045] 5. The obtained additives can significantly enhance the heat resistance, corrosion resistance, light aging resistance and a certain degree of water resistance of the coatings, and the performance is stable over a long period of time;

[0046] Therefore, the aluminum profiles prepared by this invention have excellent corrosion resistance and water resistance, and the coatings sprayed on the surface of the aluminum profiles have good wear resistance, as well as stable and efficient corrosion resistance, heat resistance and anti-photoaging properties, which have important application value in the field of aluminum profile preparation technology. Detailed Implementation

[0047] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0048] Example 1

[0049] Preparation aids:

[0050] S1. At room temperature, add 20.9g of viscous acid, 10.2g of DAST and 100mL of dichloromethane to a flask and stir until well mixed. React for 55min, filter, take the filter cake, wash 4 times with anhydrous ethanol, and dry to obtain intermediate 1.

[0051] S2. In a three-necked flask equipped with a stirring and reflux device, 22.7 g of intermediate 1, 17.1 g of pentamethylpiperidinol and N,N-dimethylformamide were mixed and stirred evenly. Then, 20.6 g of dicyclohexylcarbodiimide and 0.2 g of 4-dimethylaminopyridine were added sequentially. The reaction temperature was controlled at 80 °C and the reaction was carried out for 8 h. After the reaction was completed, the mixture was filtered, some solvent was removed by rotary evaporation, washed 3 times, and dried under vacuum to obtain intermediate 2.

[0052] S3. In a three-necked flask equipped with a stirrer, 37.1 g of intermediate 2, 7.3 g of ethylenediamine and 150 mL of N,N-dimethylformamide were mixed and stirred until homogeneous. 20.6 g of dicyclohexylcarbodiimide was added. The apparatus was placed in a water bath and reacted at 50 °C for 4 h. After the reaction was completed, the mixture was filtered, and most of the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography (using a mixed solvent of ethyl acetate and petroleum ether in a volume ratio of 2:5 as the eluent). The eluent was removed by rotary evaporation to obtain intermediate 3.

[0053] S4. In a three-necked flask equipped with a stirrer, 18.4 g of terephthalic diisocyanate, 41.3 g of intermediate 3 and 150 mL of dimethyl sulfoxide were mixed, and 2 g of tributyltin was added and stirred until homogeneous. The temperature was gradually increased to 70 °C and the reaction was maintained at this temperature for 6 h with continuous stirring. After the reaction was completed, the solvent was removed by vacuum distillation and the mixture was dried under vacuum to obtain the auxiliary agent.

[0054] Example 2

[0055] Preparation aids:

[0056] S1. At room temperature, add 41.8g of viscous acid, 20.4g of DAST and 200mL of dichloromethane to a flask and stir until well mixed. React for 55min, filter, take the filter cake, wash 4 times with anhydrous ethanol, and dry to obtain intermediate 1.

[0057] S2. In a three-necked flask equipped with a stirring and reflux device, 45.4 g of intermediate 1, 34.2 g of pentamethylpiperidinol and N,N-dimethylformamide were mixed and stirred evenly. Then, 41.2 g of dicyclohexylcarbodiimide and 0.4 g of 4-dimethylaminopyridine were added sequentially. The reaction temperature was controlled at 80 °C and the reaction was carried out for 8 h. After the reaction was completed, the mixture was filtered, some solvent was removed by rotary evaporation, washed 3 times, and dried under vacuum to obtain intermediate 2.

[0058] S3. In a three-necked flask equipped with a stirrer, 74.2 g of intermediate 2, 14.6 g of ethylenediamine and 300 mL of N,N-dimethylformamide were mixed and stirred until homogeneous. 41.2 g of dicyclohexylcarbodiimide was added. The apparatus was placed in a water bath and reacted at 50 °C for 4 h. After the reaction was completed, the mixture was filtered, and most of the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography (using a mixed solvent of ethyl acetate and petroleum ether in a volume ratio of 2:5 as the eluent). The eluent was removed by rotary evaporation to obtain intermediate 3.

[0059] S4. In a three-necked flask equipped with a stirrer, 36.8 g of terephthalic diisocyanate, 82.6 g of intermediate 3 and 300 mL of dimethyl sulfoxide were mixed, and 4 g of tributyltin was added and stirred until homogeneous. The temperature was gradually increased to 70 °C and the reaction was maintained at this temperature for 6 h with continuous stirring. After the reaction was completed, the solvent was removed by vacuum distillation and the mixture was dried under vacuum to obtain the auxiliary agent.

[0060] Example 3

[0061] Preparation of modified nano-silica:

[0062] Mix 1.0 g of nano-silica with 100 mL of ethanol aqueous solution, add to a magnetic stirrer, add a magnet, turn on the stirrer, and disperse for 15 min to ensure uniform dispersion of nano-silica in the ethanol aqueous solution. Evacuate the apparatus, introduce N2 gas, and then add 4.5 g of γ-aminopropyltriethoxysilane. Start oil bath heating, set to 50 °C, turn on the cooling water, and react at 80 °C for 4 h. Filter, wash with ethanol, and then dry in a vacuum drying oven for 2 h to obtain modified nano-silica.

[0063] Example 4

[0064] Preparation of corrosion-resistant coatings:

[0065] B1. In a three-necked flask equipped with a stirring and reflux device, 60g of bisphenol epoxy resin (epoxy value 0.54), 5g of ethylene glycol diglycidyl ether and 5g of the additive prepared in Example 1 were mixed, and then 2g of 2-ethyl-4-methylimidazole was added. After stirring and mixing, nitrogen gas was introduced and the reaction temperature was controlled at 140°C. The mixture was refluxed for 5 hours to obtain the modified epoxy resin.

[0066] B2. The modified epoxy resin obtained in step B1, 1g of ethylene glycol monobutyl ether, 0.5g of 2-methylimidazole, and 8g of the modified nano silica obtained in Example 3 are placed in a ball mill and dry-mixed for 10 hours. The mixture is then passed through a 150-mesh sieve and sieved to obtain a corrosion-resistant coating.

[0067] Example 5

[0068] Preparation of corrosion-resistant coatings:

[0069] B1. In a three-necked flask equipped with a stirring and reflux device, 70g of bisphenol epoxy resin (epoxy value 0.54), 8g of ethylene glycol diglycidyl ether and 10g of the additive prepared in Example 2 were mixed, and then 3g of 2-ethyl-4-methylimidazole was added. After stirring and mixing, nitrogen gas was introduced, the reaction temperature was controlled at 140°C, and the reaction was refluxed for 5 hours to obtain the modified epoxy resin.

[0070] B2. The modified epoxy resin obtained in step B1, 2g of polyethylene glycol octylphenyl ether, 0.1g of 3-methylimidazole, and 12g of the modified nano-silica obtained in Example 3 are placed in a ball mill and dry-mixed for 15 hours. The mixture is then passed through a 200-mesh sieve and sieved to obtain a corrosion-resistant coating.

[0071] Example 6

[0072] Preparation of corrosion-resistant coatings:

[0073] B1. In a three-necked flask equipped with a stirring and reflux device, 80g of bisphenol epoxy resin (epoxy value 0.54), 10g of ethylene glycol diglycidyl ether and 15g of the additive prepared in Example 2 were mixed, and then 4g of 2-ethyl-4-methylimidazole was added. After stirring and mixing, nitrogen gas was introduced, the reaction temperature was controlled at 140°C, and the reaction was refluxed for 5 hours to obtain the modified epoxy resin.

[0074] B2. The modified epoxy resin obtained in step B1, 3g of dodecyl carbonate, 1g of 3-methylimidazole, and 16g of the modified nano-silica obtained in Example 3 are placed in a ball mill and dry-mixed for 15 hours. The mixture is then passed through a 200-mesh sieve and sieved to obtain a corrosion-resistant coating.

[0075] Example 7

[0076] A1. After wiping the surface of the aluminum profile with acetone, immerse it in a hexadecyltrimethylammonium bromide aqueous solution (2% by mass) to degrease the surface and obtain a degreased aluminum profile.

[0077] A2. Spray micro-etching solution onto the surface of the degreased aluminum profile, clean it, dry it, and then put it into an oxidation tank for anodizing. After oxidation, wash it with water and dry it to obtain the pretreated aluminum profile.

[0078] A3. Electrostatic spraying was applied to the surface of the pretreated aluminum profile. The corrosion-resistant coating prepared in Example 5 was sprayed. The compressed air pressure was 0.5 MPa, the electrostatic spraying voltage was 40 KV, and the distance between the spray gun and the workpiece was 150 mm. After spraying, the profile was placed in a curing chamber for curing. The curing temperature was 200℃ and the curing time was 1 hour. After curing, the profile was allowed to cool naturally to room temperature to obtain a corrosion-resistant industrial aluminum profile.

[0079] The micro-etching solution is prepared by mixing hydrochloric acid, phosphoric acid, triethanolamine, diammonium hydrogen phosphate and water in a mass ratio of 1:1:1:2:30.

[0080] Example 8

[0081] A1. After wiping the surface of the aluminum profile with acetone, immerse it in a hexadecyltrimethylammonium bromide aqueous solution (2% by mass) to degrease the surface and obtain a degreased aluminum profile.

[0082] A2. Spray micro-etching solution onto the surface of the degreased aluminum profile, clean it, dry it, and then put it into an oxidation tank for anodizing. After oxidation, wash it with water and dry it to obtain the pretreated aluminum profile.

[0083] A3. Electrostatic spraying was applied to the surface of the pretreated aluminum profile using the corrosion-resistant coating prepared in Example 6. The compressed air pressure during spraying was 0.7 MPa, the electrostatic spraying voltage was 60 KV, and the distance between the spray gun and the workpiece was 200 mm. After spraying, the profile was placed in a curing chamber for curing at a curing temperature of 220°C for 2 hours. After curing, the profile was allowed to cool naturally to room temperature to obtain a corrosion-resistant industrial aluminum profile.

[0084] The micro-etching solution is prepared by mixing hydrochloric acid, phosphoric acid, triethanolamine, diammonium hydrogen phosphate and water in a mass ratio of 1:4:3:4:40.

[0085] Comparative Example 1

[0086] Without adding any additives, the remaining steps are the same as in Example 6, and the coating is obtained.

[0087] Comparative Example 2

[0088] Use commercially available corrosion-resistant coatings.

[0089] Examples 4, 5, and 6, and Comparative Examples 1 and 2, were subjected to the following performance tests according to different testing standards:

[0090] The adhesion of the samples before and after standing at 180℃ for 12 hours was determined according to the national standard GB / T 9286-2021 "Cross-cut test method for paints and varnishes".

[0091] Impact resistance was determined according to the national standard GB / T 1732-2020 "Test Method for Impact Resistance of Coating Films";

[0092] The water resistance was determined by immersion test according to the national standard GB / T 1733-1993 "Determination of Water Resistance of Paint Films";

[0093] The anti-photoaging performance was determined according to the national standard GB / T 1865-2009 and rated according to the standard GB / T 1766.

[0094] The abrasion resistance was determined using the national standard GB / T 23988-2009 "Determination of Abrasion Resistance of Coatings - Falling Sand Method".

[0095] The acid and alkali resistance was determined according to the national standard GB / T 1763 "Determination of Chemical Resistance of Coatings".

[0096] Salt spray resistance was determined according to the national standard GB / T1771-1991 "Determination of resistance to neutral salt spray of paints and varnishes";

[0097]

[0098]

[0099] As can be seen from the table above, the coating prepared by the embodiments of the present invention has good wear resistance, as well as stable and efficient corrosion resistance, heat resistance and photoaging resistance. Spraying it on the surface of aluminum profiles can improve the various properties of aluminum profiles. Therefore, the present invention has important application value in the field of aluminum profile preparation technology.

[0100] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0101] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A method for manufacturing a corrosion-resistant industrial aluminum profile, characterized in that, Includes the following steps: A1. After wiping the surface of the aluminum profile with acetone, immerse it in an aqueous solution of hexadecyltrimethylammonium bromide to degrease the surface and obtain a degreased aluminum profile. A2. Spray micro-etching solution onto the surface of the degreased aluminum profile, clean it, dry it, and then put it into an oxidation tank for anodizing. After oxidation, wash it with water and dry it to obtain the pretreated aluminum profile. A3. Electrostatic spraying is applied to the surface of the pretreated aluminum profile to apply a corrosion-resistant coating. After spraying, the coating is cured and cooled to obtain a corrosion-resistant industrial aluminum profile. The corrosion-resistant coating described in step A3 is prepared through the following steps: B1. Mix bisphenol epoxy resin, ethylene glycol diglycidyl ether and additives, then add 2-ethyl-4-methylimidazole, stir and mix, purge with nitrogen, and reflux at 140°C for 5 hours to obtain modified epoxy resin. B2. The modified epoxy resin, film-forming aid, curing accelerator, and modified nano-silica obtained in step B1 are put into a ball mill for dry mixing, sieved, and screened to obtain a corrosion-resistant coating. The auxiliary agent is prepared through the following steps: S1. At room temperature, add viscous acid, diethylaminotrifluoride and dichloromethane to a flask and stir to mix evenly. React for 55 min, filter, take the filter cake, wash and dry to obtain intermediate 1. S2. Mix intermediate 1, pentamethylpiperidinol and N,N-dimethylformamide evenly, then add dicyclohexylcarbodiimide and 4-dimethylaminopyridine sequentially. React at 80°C for 8 hours. After the reaction is complete, filter, rotary evaporate, wash and vacuum dry to obtain intermediate 2. S3. Mix intermediate 2, ethylenediamine and N,N-dimethylformamide evenly, add dicyclohexylcarbodiimide, react at 50°C for 4 hours, filter, rotary evaporate, purify by column chromatography, and rotary evaporate to obtain intermediate 3. S4. Mix terephthalic diisocyanate, intermediate 3 and dimethyl sulfoxide, add tributyltin and stir until homogeneous. Keep the mixture at 70°C for 6 hours with constant stirring during the reaction. After the reaction is complete, distill under reduced pressure and dry to obtain the auxiliary agent. The modified nano-silica is prepared through the following steps: Nano-silica was mixed with an ethanol aqueous solution and added to a magnetic stirring device. A magnet was added, and the stirring was started. The mixture was dispersed for 15 minutes to ensure that the nano-silica was evenly dispersed in the ethanol aqueous solution. The device was then evacuated, and N2 gas was introduced. γ-aminopropyltriethoxysilane was added, and oil bath heating was started at 50°C. The cooling water was turned on, and the reaction was carried out at 80°C for 4 hours. The mixture was then filtered, washed with ethanol, and dried in a vacuum drying oven for 2 hours to obtain modified nano-silica.

2. The method for manufacturing a corrosion-resistant industrial aluminum profile according to claim 1, characterized in that, In step S1, the ratio of viscous acid, diethylaminosulfuric acid, and dichloromethane is 20.9 g: 10.2 g: 100 mL.

3. The method for manufacturing a corrosion-resistant industrial aluminum profile according to claim 1, characterized in that, In step S2, the ratio of intermediate 1, pentamethylpiperidinol, N,N-dimethylformamide, dicyclohexylcarbodiimide, and 4-dimethylaminopyridine is 22.7 g: 17.1 g: 150 mL: 20.6 g: 0.2 g.

4. The method for manufacturing a corrosion-resistant industrial aluminum profile according to claim 1, characterized in that, In step S3, the ratio of intermediate 2, ethylenediamine, N,N-dimethylformamide, and dicyclohexylcarbodiimide is 37.1g:7.3g:150mL:20.6g.

5. The method for manufacturing a corrosion-resistant industrial aluminum profile according to claim 1, characterized in that, In step S4, the ratio of the amounts of phenyl diisocyanate, intermediate 3, dimethyl sulfoxide, and tributyltin is 18.4 g: 41.3 g: 150 mL: 2 g.

6. The method for manufacturing a corrosion-resistant industrial aluminum profile according to claim 1, characterized in that, The raw materials of the corrosion-resistant coating are as follows by weight: 60-80 parts bisphenol epoxy resin, 5-10 parts ethylene glycol diglycidyl ether, 5-15 parts additives, 2-4 parts 2-ethyl-4-methylimidazole, 1-3 parts film-forming aid, 0.5-1 part curing accelerator, and 8-16 parts modified nano silica.

7. The method for manufacturing a corrosion-resistant industrial aluminum profile according to claim 1, characterized in that, In step A2, the micro-etching solution is prepared by mixing hydrochloric acid, phosphoric acid, triethanolamine, diammonium hydrogen phosphate and water in a mass ratio of 1:1-4:1-3:2-4:30-40.

8. A corrosion-resistant industrial aluminum profile, characterized in that, It is prepared by the manufacturing method according to any one of claims 1-7.

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