A water-based high-temperature resistant electrochemical aluminum coating and its preparation method

Abstract

The present invention relates to a water-based, high-temperature-resistant electrochemical aluminum coating and a preparation method thereof, belonging to the technical field of coating preparation. The water-based, high-temperature-resistant electrochemical aluminum coating comprises the following raw materials: an organosilicon-modified water-based acrylic emulsion, a high-Tg water-based acrylic emulsion, a diluent, a surface control additive, and an anticorrosive and antifungal agent; wherein the organosilicon-modified water-based acrylic emulsion further comprises the following raw materials: a hard monomer, a soft monomer, a functional monomer, an initiator, an anionic surfactant, a nonionic surfactant, a silicon-containing organic matter, an organic solvent, a salt-forming agent, and deionized water. The water-based, high-temperature-resistant electrochemical aluminum coating prepared by the present invention does not contain a high content of organic solvents and has a low VOC content, thereby improving the problems of traditional solvent-based electrochemical aluminum coatings, such as high VOC content, strong odor, and a narrow application range, as well as the low temperature resistance and poor water resistance of existing water-based acrylic electrochemical aluminum coatings.

Description

Technical Field

[0001] The present invention belongs to the technical field of coating preparation, and in particular relates to a water-based high-temperature resistant electrochemical aluminum coating and a preparation method thereof. Background Art

[0002] In many industrial fields, such as automobile manufacturing, electronic equipment and building materials, the surface protection of aluminum is of vital importance. Water-based high-temperature resistant electrochemical aluminum coating is a coating used to protect the surface of aluminum, which needs to have good high-temperature resistance, water resistance, etc. Traditional solvent-based electrochemical aluminum coatings have high VOC content, strong odor, and a narrow range of use. The existing water-based acrylic electrochemical aluminum coatings have low temperature resistance and poor water resistance, which can easily lead to a decrease in the performance of the coating and seriously affect the application. Therefore, in order to overcome these problems, it is particularly important to develop a water-based high-temperature resistant electrochemical aluminum coating to meet the needs of aluminum surface protection by improving the formula and adding functional additives. The successful development of this coating will have broad application prospects in multiple industrial fields. Summary of the Invention

[0003] The purpose of the present invention is to provide a water-based high-temperature resistant electrochemical aluminum coating and a preparation method thereof, so that the prepared water-based high-temperature resistant electrochemical aluminum coating does not contain a high content of organic solvents and has a low VOC content, thereby solving the problems of poor high-temperature resistance and water resistance in the existing electrochemical aluminum coating technology.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A water-based high-temperature resistant electrochemical aluminum coating, comprising the following raw materials in parts by weight:

[0006] 60-100 parts by weight of organosilicon-modified water-based acrylic emulsion, 5-20 parts by weight of high Tg water-based acrylic emulsion, 20-150 parts by weight of diluent, 0.1-2 parts by weight of surface control additive, and 0.1-2 parts by weight of antiseptic and mildew inhibitor.

[0007] As a preferred embodiment of the present invention, the high Tg water-based acrylic emulsion includes any one of Joncryl-1695 and Joncryl-660. Preferably, Joncryl-1695 is selected in the present invention.

[0008] As a preferred embodiment of the present invention, the diluent includes at least one of deionized water, methanol, ethanol, and isopropanol. Preferably, the present invention uses deionized water and isopropanol.

[0009] As a preferred embodiment of the present invention, the surface control agent consists of an aqueous defoamer and an aqueous leveling agent.

[0010] As a preferred embodiment of the present invention, the aqueous defoaming agent is TEGO foamex 810 aqueous defoaming agent with the brand name TEGO foamex 810.

[0011] As a preferred embodiment of the present invention, the water-based leveling agent is Dow Corning DC 51 water-based leveling agent with the brand model number of Dow Corning DC 51.

[0012] As a preferred embodiment of the present invention, the antiseptic and mildew preventer is any one of Kathon KN-16A antiseptic and mildew preventer with the Kathon brand trademark KN-16A and Kathon LY-1002 antiseptic and mildew preventer with the Kathon brand trademark LY-1002. Preferably, the present invention uses Kathon LY-1002 antiseptic and mildew preventer.

[0013] As a preferred embodiment of the present invention, the organosilicon-modified water-based acrylic emulsion comprises the following raw materials in parts by weight:

[0014] 20-70 parts by weight of hard monomer, 10-40 parts by weight of soft monomer, 5-10 parts by weight of functional monomer, 0.2-0.8 parts by weight of initiator, 0-5 parts by weight of anionic surfactant, 0-5 parts by weight of nonionic surfactant, 6-10 parts by weight of silicon-containing organic matter, 10-30 parts by weight of organic solvent, and 100-140 parts by weight of deionized water.

[0015] As a preferred embodiment of the present invention, the organosilicon-modified aqueous acrylic emulsion further comprises a salt-forming agent.

[0016] As a preferred embodiment of the present invention, the salt-forming agent is any one of potassium hydroxide, sodium hydroxide, ammonia water, triethylamine, N-methyldiethanolamine, and triethanolamine. Preferably, ammonia water is selected in the present invention.

[0017] As a preferred embodiment of the present invention, the hard monomer includes at least one of methyl methacrylate, vinyl acetate, styrene, and methacrylamide. Preferably, the present invention uses methyl methacrylate and styrene.

[0018] As a preferred solution of the present invention, the soft monomer includes any one of butyl acrylate, ethyl acrylate, and isooctyl acrylate. Preferably, butyl acrylate is selected in the present invention.

[0019] As a preferred embodiment of the present invention, the functional monomer includes at least one of methacrylic acid, acrylic acid, 2-hydroxyethyl methacrylate and tert-butyl glycidyl ester. Preferably, the present invention uses acrylic acid, 2-hydroxyethyl methacrylate and tert-butyl glycidyl ester.

[0020] As a preferred embodiment of the present invention, the initiator includes any one of benzoyl peroxide and azobisisobutyronitrile. Preferably, azobisisobutyronitrile is selected in the present invention.

[0021] As a preferred embodiment of the present invention, the anionic surfactant includes any one of SDS, sulfonate, and sulfate ester salt. Preferably, SDS is selected in the present invention.

[0022] As a preferred embodiment of the present invention, the nonionic surfactant is a polyoxyethylene nonionic surfactant or a polyol nonionic surfactant.

[0023] As a preferred embodiment of the present invention, the polyoxyethylene nonionic surfactant includes any one of AEO, OP-10, and polyoxyethylene amide; the polyol nonionic surfactant includes any one of anhydrous sorbitol ester and sucrose ester; preferably, AEO is selected in the present invention.

[0024] As a preferred embodiment of the present invention, the silicon-containing organic compound includes any one of vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. Preferably, the present invention uses γ-methacryloxypropyltrimethoxysilane.

[0025] As a preferred embodiment of the present invention, the organic solvent includes any one of N,N-dimethylformamide, N-methylpyrrolidone, isopropyl alcohol, and acetone. Preferably, isopropyl alcohol is used in the present invention.

[0026] As a preferred embodiment of the present invention, the method for preparing the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps:

[0027] S1. Add hard monomer, soft monomer, functional monomer, initiator, anionic surfactant and nonionic surfactant to the container in sequence, and stir at a controlled speed until the mixture is uniform to form a mixture A, which is set aside;

[0028] S2, stirring and heating the organic solvent and the silicon-containing organic matter, reflux, and after the reflux stabilizes, adding the mixture A dropwise at a controlled time, then heating and keeping the temperature to react, to obtain the mixture B;

[0029] S3. Cool the mixed material B to below 50° C., add a salt-forming agent to adjust the pH of the system, continue stirring, add 3 / 5 of the mass of deionized water and stir at a controlled speed, then remove the organic solvent, add the remaining mass of deionized water and stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

[0030] As a preferred embodiment of the present invention, the temperature of the speed-controlled stirring in step S1 is 290-310 r / min, and the time is 10-15 min.

[0031] As a preferred embodiment of the present invention, the stirring and heating in step S2 is stirring and heating to 80-85°C; the time for the time-controlled dropwise addition of the mixture A is 60-100 minutes; and the heating and heat preservation reaction is specifically heating to 75-85°C and heat preservation reaction for 3-4 hours.

[0032] As a preferred solution of the present invention, the pH value of the adjustment system in step S3 is 7-8; the time of continuing stirring is 9-11 minutes; and the speed of controlling the stirring uniformly is 800-1000 r / min.

[0033] A method for preparing a water-based high-temperature resistant electrochemical aluminum coating, the method comprising the following steps:

[0034] Weigh the raw materials according to the formula, add the weighed diluent into the reactor, then add silicone-modified water-based acrylic emulsion, high Tg water-based acrylic emulsion, surface control additive and anti-corrosion and anti-mildew agent, control the temperature and stir evenly, filter, and obtain the finished product of water-based high-temperature resistant electrochemical aluminum coating.

[0035] As a preferred solution of the present invention, the temperature for temperature control and uniform stirring is 0-80°C; and the filtration is performed using a 300-mesh filter.

[0036] Beneficial effects of the present invention:

[0037] (1) The present invention selects monomers containing carboxyl groups in the side chains and functional monomers with epoxy groups in the synthesis of the organosilicon-modified water-based acrylic emulsion, compounds the hard monomers, soft monomers and functional monomers, and polymerizes them under appropriate reaction conditions to react the carboxyl groups with the epoxy groups, thereby reducing the viscosity of the entire organosilicon-modified water-based acrylic emulsion system. The organosilicon-modified water-based acrylic emulsion is used in the preparation of electrochemical aluminum coatings, thereby enhancing the self-leveling effect of the electrochemical aluminum coatings and making the film surface of the finished electrochemical aluminum coatings have a mirror effect, which not only improves the appearance but also improves the hydrophobicity and wear resistance of the electrochemical aluminum coatings to a certain extent.

[0038] (2) The present invention adopts siloxane containing terminal vinyl groups for modification polymerization in the synthesis of the organosilicon-modified water-based acrylic emulsion, especially adopts γ-methacryloxypropyltrimethoxysilane. Under the action of the initiator, the system undergoes a free radical polymerization reaction, thereby improving the crosslinking density of the organosilicon-modified water-based acrylic emulsion system. The organosilicon-modified water-based acrylic emulsion is used in the preparation of electrochemical aluminum coating, which greatly improves the heat decomposition resistance and water immersion resistance of the finished electrochemical aluminum coating.

[0039] (3) In the preparation process of the water-based high-temperature resistant electrochemical aluminum coating of the present invention, a high-Tg water-based acrylic emulsion is compounded and modified with a silicone-modified water-based acrylic emulsion. Since the selected high-Tg water-based acrylic emulsion has excellent film-forming properties and good temperature resistance, after being mixed with the silicone-modified water-based acrylic emulsion, the film-forming effect can be further improved without reducing its temperature resistance, thereby ensuring the smoothness of the coating and further improving it, and the smooth effect of the silicone-modified resin can be brought into play, thereby obtaining better application performance.

[0040] (4) The water-based high-temperature resistant electrochemical aluminum coating prepared by the present invention does not contain a high content of organic solvents and has a low VOC content, thereby improving the problems of traditional solvent-based electrochemical aluminum coatings such as high VOC content, strong odor, and narrow scope of use, as well as the low temperature resistance and poor water resistance of existing water-based acrylic electrochemical aluminum coatings. DETAILED DESCRIPTION

[0041] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0042] Example 1

[0043] Prepare an organosilicon-modified water-based acrylic emulsion, which includes the following raw materials in parts by weight:

[0044]

[0045] The organosilicon-modified water-based acrylic emulsion further includes a salt-forming agent; the salt-forming agent is ammonia water;

[0046] The preparation method of the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps:

[0047] S1. Add methyl methacrylate, styrene, butyl acrylate, acrylic acid, 2-hydroxyethyl methacrylate, glycidyl versatate and azobisisobutyronitrile to a container in sequence, and stir at a controlled speed of 290 r / min for 15 min until the mixture is uniform to form a mixture A, which is set aside;

[0048] S2. Stirring isopropyl alcohol and γ-methacryloxypropyltrimethoxysilane and heating them to 80° C., reflux, and after the reflux stabilizes, adding mixture A dropwise over a period of 100 min. Then, heating to 75° C. and keeping the temperature for 3 h to obtain mixture B.

[0049] S3. Cool the mixture B to 40°C, add ammonia water to adjust the pH of the system to 7, continue stirring for 11 minutes, add 3 / 5 of the mass of deionized water and stir at a speed of 800 r / min, then remove the isopropyl alcohol, add the remaining mass of deionized water and stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

[0050] Example 2

[0051] Prepare an organosilicon-modified water-based acrylic emulsion, which includes the following raw materials in parts by weight:

[0052]

[0053] The organosilicon-modified waterborne acrylic emulsion further includes a salt-forming agent; the salt-forming agent is potassium hydroxide;

[0054] The preparation method of the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps:

[0055] S1. Add vinyl acetate, methacrylamide, isooctyl acrylate, methacrylic acid, acrylic acid, 2-hydroxyethyl methacrylate, benzoyl peroxide, SDS, and AEO to a container in sequence, and stir at a controlled speed of 300 r / min for 10 min until uniformly mixed to form a mixture A, which is set aside;

[0056] S2. Stir and heat N,N-dimethylformamide and vinyltriethoxysilane to 85° C., reflux, and after the reflux stabilizes, add mixture A dropwise over 80 min, then raise the temperature to 85° C. and keep the temperature for 4 h to obtain mixture B;

[0057] S3. Cool the mixed material B to 45°C, add potassium hydroxide to adjust the pH of the system to 8, continue stirring for 9 minutes, add 3 / 5 of the mass of deionized water and stir at a controlled speed of 900 r / min, then remove N,N-dimethylformamide, add the remaining mass of deionized water and stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

[0058] Example 3

[0059] Prepare an organosilicon-modified water-based acrylic emulsion, which includes the following raw materials in parts by weight:

[0060]

[0061] The organosilicon-modified waterborne acrylic emulsion further comprises a salt-forming agent; the salt-forming agent is triethylamine;

[0062] The preparation method of the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps:

[0063] S1. Add methyl methacrylate, methacrylamide, ethyl acrylate, methacrylic acid, acrylic acid, glycidyl ester of versatate, azobisisobutyronitrile, SDS and AEO to a container in sequence, and stir at a speed of 300 r / min for 10 min until the mixture is uniform to form a mixture A, which is set aside;

[0064] S2, stirring and heating N-methylpyrrolidone and γ-aminopropyltriethoxysilane to 83° C., reflux, and after the reflux stabilizes, add mixture A dropwise over 60 minutes, then raise the temperature to 80° C. and keep the temperature for 3.5 hours to obtain mixture B;

[0065] S3. Cool the mixture B to 48°C, add triethylamine to adjust the pH of the system to 7.5, continue stirring for 10 minutes, add 3 / 5 of the mass of deionized water and stir at a speed of 1000 r / min, then remove the N-methylpyrrolidone, add the remaining mass of deionized water and stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

[0066] Example 4

[0067] Prepare an organosilicon-modified water-based acrylic emulsion, which includes the following raw materials in parts by weight:

[0068]

[0069] The organosilicon-modified water-based acrylic emulsion further includes a salt-forming agent; the salt-forming agent is ammonia water;

[0070] The preparation method of the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps:

[0071] S1. Add methyl methacrylate, styrene, butyl acrylate, acrylic acid, 2-hydroxyethyl methacrylate, glycidyl tert-butyl carbonate, benzoyl peroxide, SDS, and AEO to a container in sequence, and stir at a controlled speed of 295 r / min for 12 min until uniformly mixed to form a mixture A, which is set aside;

[0072] S2. Stir and heat acetone and γ-methacryloxypropyltrimethoxysilane to 82° C., reflux, and add mixture A dropwise over 70 min after the reflux stabilizes. Then, raise the temperature to 78° C. and keep the temperature for 3 h to obtain mixture B.

[0073] S3. Cool the mixture B to 42°C, add ammonia water to adjust the pH of the system to 8, continue stirring for 10 minutes, add 3 / 5 of the mass of deionized water and stir at a controlled speed of 850 r / min, then remove the acetone, add the remaining mass of deionized water and stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

[0074] Example 5

[0075] Prepare an organosilicon-modified water-based acrylic emulsion, which includes the following raw materials in parts by weight:

[0076]

[0077] The organosilicon-modified water-based acrylic emulsion further includes a salt-forming agent; the salt-forming agent is ammonia water;

[0078] The preparation method of the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps:

[0079] S1. Add methyl methacrylate, styrene, butyl acrylate, acrylic acid, 2-hydroxyethyl methacrylate, glycidyl ester of versatate, azobisisobutyronitrile, SDS and AEO to a container in sequence, and stir at a controlled speed of 310 r / min for 13 min until the mixture is uniformly mixed to form a mixture A, which is set aside;

[0080] S2. Stirring isopropyl alcohol and γ-aminopropyltriethoxysilane and heating them to 83° C., reflux, and after the reflux stabilizes, adding mixture A dropwise over 60 min, then raising the temperature to 83° C. and keeping the temperature for reaction for 3.5 h to obtain mixture B;

[0081] S3. Cool the mixture B to 46°C, add ammonia water to adjust the pH of the system to 7.5, continue stirring for 10 minutes, add 3 / 5 of the mass of deionized water, control the speed to 950 r / min and stir evenly, then remove the isopropyl alcohol, add the remaining mass of deionized water, stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

[0082] Example 6

[0083] A water-based high-temperature resistant electrochemical aluminum coating, comprising the following raw materials in parts by weight:

[0084]

[0085] The preparation method comprises the following steps:

[0086] The raw materials were weighed according to the formula, and the weighed deionized water and isopropyl alcohol were added to the reactor. The silicone-modified water-based acrylic emulsion prepared in Example 1, Joncryl-1695, TEGO foamex 810, Dow Corning DC 51 and Kathon LY-1002 were then added and stirred at 40°C. After stirring, the mixture was filtered through a 300-mesh filter to obtain a finished water-based high-temperature resistant electrochemical aluminum coating.

[0087] According to the standard GB-239862009, the VOC content of the finished water-based high-temperature resistant electrochemical aluminum coating prepared in this embodiment is 0.04 g / mL.

[0088] Example 7

[0089] A water-based high-temperature resistant electrochemical aluminum coating, comprising the following raw materials in parts by weight:

[0090]

[0091] The preparation method comprises the following steps:

[0092] The raw materials were weighed according to the formula, and the weighed methanol and isopropanol were added to the reactor. The silicone-modified water-based acrylic emulsion prepared in Example 5, Joncryl-660, TEGO foamex 810, Dow Corning DC 51 and Kathon KN-16A were then added and stirred evenly at 0°C. After stirring, the mixture was filtered through a 300-mesh filter to obtain a finished water-based high-temperature resistant electrochemical aluminum coating.

[0093] According to the standard GB-239862009, the VOC content of the finished water-based high-temperature resistant electrochemical aluminum coating prepared in this embodiment is 0.05 g / mL.

[0094] Example 8

[0095] A water-based high-temperature resistant electrochemical aluminum coating, comprising the following raw materials in parts by weight:

[0096]

[0097]

[0098] The preparation method comprises the following steps:

[0099] The raw materials were weighed according to the formula, and the weighed ethanol and isopropanol were added to the reactor. The organosilicon-modified water-based acrylic emulsion prepared in Example 4, Joncryl-1695, TEGO foamex 810, Dow Corning DC 51 and Kathon LY-1002 were then added and stirred at 20°C. After stirring, the mixture was filtered through a 300-mesh filter to obtain a finished water-based high-temperature resistant electrochemical aluminum coating.

[0100] According to the standard GB-239862009, the VOC content of the finished water-based high-temperature resistant electrochemical aluminum coating prepared in this embodiment is 0.05 g / mL.

[0101] Example 9

[0102] A water-based high-temperature resistant electrochemical aluminum coating, comprising the following raw materials in parts by weight:

[0103]

[0104] The preparation method comprises the following steps:

[0105] The raw materials were weighed according to the formula, and the weighed deionized water and methanol were added to the reactor. The silicone-modified water-based acrylic emulsion prepared in Example 3, Joncryl-1695, TEGO foamex 810, Dow Corning DC 51 and Kathon KN-16A were then added and stirred at 80°C. After stirring, the mixture was filtered through a 300-mesh filter to obtain a finished water-based high-temperature resistant electrochemical aluminum coating.

[0106] According to the standard GB-239862009, the VOC content of the finished water-based high-temperature resistant electrochemical aluminum coating prepared in this embodiment is 0.04 g / mL.

[0107] Example 10

[0108] A water-based high-temperature resistant electrochemical aluminum coating, comprising the following raw materials in parts by weight:

[0109]

[0110] The preparation method comprises the following steps:

[0111] The raw materials were weighed according to the formula, and the weighed deionized water and ethanol were added to the reactor. The silicone-modified water-based acrylic emulsion prepared in Example 2, Joncryl-660, TEGO foamex 810, Dow Corning DC 51 and Kathon KN-16A were then added and the mixture was stirred evenly at 60° C. After stirring, the mixture was filtered through a 300-mesh filter to obtain a finished water-based high-temperature resistant electrochemical aluminum coating.

[0112] According to the standard GB-239862009, the VOC content of the finished water-based high-temperature resistant electrochemical aluminum coating prepared in this embodiment is 0.05 g / mL.

[0113] Comparative Examples 1-3

[0114] Compared with Example 1, the weight proportions of the hard monomer, soft monomer and functional monomer in Comparative Examples 1-3 are shown in Table 1, and the remaining operating steps and parameters remain unchanged.

[0115] Table 1

[0116]

[0117]

[0118] Comparative Example 4

[0119] Compared with Example 1, in Comparative Example 4, methyl methacrylate is 0 parts by weight, styrene is 20 parts by weight, and the other operating steps and parameters remain unchanged.

[0120] Comparative Example 5

[0121] Compared with Example 1, in Comparative Example 5, the amount of methyl methacrylate was 20 parts by weight, the amount of styrene was 0 parts by weight, and the other operating steps and parameters remained unchanged.

[0122] Comparative Example 6

[0123] Compared with Example 1, in Comparative Example 6, acrylic acid is 0 parts by weight, 2-hydroxyethyl methacrylate is 3.5 parts by weight, and versatile glycidyl carbonate is 4 parts by weight, and the other operating steps and parameters remain unchanged.

[0124] Comparative Example 7

[0125] Compared with Example 1, in Comparative Example 7, acrylic acid is 4 parts by weight, 2-hydroxyethyl methacrylate is 0 parts by weight, and versatile glycidyl carbonate is 3.5 parts by weight, and the other operating steps and parameters remain unchanged.

[0126] Comparative Example 8

[0127] Compared with Example 1, in Comparative Example 8, acrylic acid is 4.2 parts by weight, 2-hydroxyethyl methacrylate is 3.3 parts by weight, and versatile glycidyl carbonate is 0 parts by weight, and the other operating steps and parameters remain unchanged.

[0128] Comparative Example 9

[0129] Compared with Example 1, the difference is that in Comparative Example 9, γ-methacryloxypropyltrimethoxysilane is not added, and the other operating steps and parameters remain unchanged.

[0130] Comparative Examples 10-18

[0131] Compared with Example 6, the difference between Comparative Examples 10-18 is that the organosilicon-modified waterborne acrylic emulsion prepared in Example 1 in Example 6 is replaced by the organosilicon-modified waterborne acrylic emulsion prepared in Comparative Examples 1-9, respectively, and the other operating steps and parameters remain unchanged.

[0132] Comparative Example 19

[0133] Compared with Example 6, the difference is that in Comparative Example 19, the organosilicon-modified water-based acrylic emulsion prepared in Example 1 is 85 parts by weight, and Joncryl-1695 is 0 parts by weight, and the other operating steps and parameters remain unchanged.

[0134] Comparative Example 20

[0135] Compared with Example 6, the difference is that in Comparative Example 20, the organosilicon-modified water-based acrylic emulsion prepared in Example 1 is 0 parts by weight, Joncryl-1695 is 85 parts by weight, and the other operating steps and parameters remain unchanged.

[0136] Test Example 1

[0137] High temperature resistance test:

[0138] According to the standard GB / T 1735-2009, the heat resistance test was performed on the electrochemical aluminum coatings prepared in Examples 6-10 and Comparative Examples 18-20. The results are shown in Table 2.

[0139] Table 2

[0140] High temperature resistance Example 6 160℃, 30min without discoloration of coating Example 7 160℃, 30min without discoloration of coating Example 8 160℃, 30min without discoloration of coating Example 9 160℃, 30min without discoloration of coating Example 10 160℃, 30min without discoloration of coating Comparative Example 18 160℃, 30min coating changes color slightly Comparative Example 19 160℃, 30min coating changes color obviously Comparative Example 20 160℃, 30min coating changes color obviously

[0141] It can be seen from Table 2 of the water-based high-temperature resistant electrochemical aluminum coating that the high-temperature resistant performance of the coating prepared by the present invention is outstanding.

[0142] Test Example 2

[0143] (1) Water resistance test: According to the standard GB / T 1733-1993, the electrochemical aluminum coatings prepared in Examples 6-10 and Comparative Examples 10-18 were subjected to a water immersion resistance test by immersing in a 25°C water bath for 168 hours to observe whether the coatings were peeling off. The results are shown in Table 3.

[0144] (2) Wear resistance test: According to the standard ASTM F2496, the electrochemical aluminum coatings prepared in Examples 6-10, Comparative Examples 10-17 and Comparative Examples 19-20 were subjected to heat resistance tests using a Biacore reciprocating wear tester at 10 N, 30 rpm, and 40 reciprocating times to observe whether the coatings were scratched or discolored. The results are shown in Table 3.

[0145] Table 2

[0146]

[0147]

[0148] As can be seen from Table 3, the electrochemical aluminum coating prepared in the present invention has outstanding water resistance and wear resistance.

[0149] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these 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 any one or more embodiments or examples.

[0150] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A water-based high-temperature resistant electrochemical aluminum coating, characterized in that: The water-based high-temperature resistant electrochemical aluminum coating comprises the following raw materials in parts by weight: 60-100 parts by weight of silicone-modified water-based acrylic emulsion, 5-20 parts by weight of high Tg water-based acrylic emulsion, 20-150 parts by weight of diluent, 0.1-2 parts by weight of surface control additive, and 0.1-2 parts by weight of antiseptic and mildew inhibitor; The organosilicon-modified water-based acrylic emulsion comprises the following raw materials in parts by weight: 20-70 parts by weight of hard monomer, 10-40 parts by weight of soft monomer, 5-10 parts by weight of functional monomer, 0.2-0.8 parts by weight of initiator, 0-5 parts by weight of anionic surfactant, 0-5 parts by weight of nonionic surfactant, 6-10 parts by weight of silicon-containing organic matter, 10-30 parts by weight of organic solvent, and 100-140 parts by weight of deionized water; The functional monomers are acrylic acid, 2-hydroxyethyl methacrylate and tert-butyl glycidyl ester; The high Tg water-based acrylic emulsion includes any one of Joncryl-1695 and Joncryl-660; The silicon-containing organic compound includes any one of vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

2. The water-based high-temperature resistant electrochemical aluminum coating according to claim 1, characterized in that: The surface control auxiliary agent consists of a water-based defoamer and a water-based leveling agent.

3. The water-based high-temperature resistant electrochemical aluminum coating according to claim 1, characterized in that: The organosilicon-modified aqueous acrylic emulsion further includes a salt-forming agent.

4. The water-based high-temperature resistant electrochemical aluminum coating according to claim 1, characterized in that: The hard monomer includes at least one of methyl methacrylate, vinyl acetate, styrene, and methacrylamide.

5. The water-based high-temperature resistant electrochemical aluminum coating according to claim 1, characterized in that: The soft monomer includes any one of butyl acrylate, ethyl acrylate and isooctyl acrylate.

6. The water-based high-temperature resistant electrochemical aluminum coating according to claim 3, characterized in that: The preparation method of the organosilicon-modified water-based acrylic emulsion specifically comprises the following steps: S1. Add hard monomer, soft monomer, functional monomer, initiator, anionic surfactant and nonionic surfactant to the container in sequence, and stir at a controlled speed until the mixture is uniform to form a mixture A, which is set aside; S2, stirring and heating the organic solvent and the silicon-containing organic matter, reflux, and after the reflux stabilizes, adding the mixture A dropwise at a controlled time, then heating and keeping the temperature to react, to obtain the mixture B; S3. Cool the mixed material B to below 50° C., add a salt-forming agent to adjust the pH of the system, continue stirring, add 3 / 5 of the mass of deionized water and stir at a controlled speed, then remove the organic solvent, add the remaining mass of deionized water and stir evenly, and discharge the material to obtain a silicone-modified water-based acrylic emulsion.

7. A method for preparing a water-based high-temperature resistant electrochemical aluminum coating according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: Weigh the raw materials according to the formula, add the weighed diluent into the reactor, then add silicone-modified water-based acrylic emulsion, high Tg water-based acrylic emulsion, surface control additive and anti-corrosion and anti-mildew agent, control the temperature and stir evenly, filter, and obtain the finished product of water-based high-temperature resistant electrochemical aluminum coating.

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