Water-based adhesive for nano-ceramic molding and preparation method and application thereof

Abstract

The application belongs to the technical field of ceramic adhesive and specifically relates to a water-based adhesive for nano ceramic forming and a preparation method and application thereof. The water-based adhesive for nano ceramic forming comprises the following raw materials and is prepared according to the mass percentage: 20-30% of acrylic monomer, 15-30% of long side chain unsaturated carboxylic acid, 2.5-4% of hydroxy acrylamide, 15-25% of water-soluble plasticizer, 0.5-2% of unsaturated carboxylic acid vinyl ester, 25-35% of hydrophilic solvent and 0.2-0.5% of initiator. The water-based adhesive for nano ceramic forming can not only give the ceramic green body high strength and high flexibility, but also keep excellent thermal decomposition characteristics and stable performance of the novel water-based adhesive. The application further provides a preparation method of the water-based adhesive for nano ceramic forming and application of the water-based adhesive in nano ceramic forming.

Description

Technical Field

[0001] This invention belongs to the field of ceramic adhesives technology, specifically relating to water-based adhesives for nano-ceramic molding, their preparation methods, and applications. Background Technology

[0002] Ceramic materials, especially high-performance structural ceramics such as zirconia, are widely used in engineering structures due to their mechanical properties, including high hardness, high wear resistance, low coefficient of thermal expansion, and excellent chemical stability. One typical application is ceramic bearing rings, which exhibit significant advantages over traditional metal bearings in harsh conditions such as high-speed operation, heavy loads, and large temperature variations.

[0003] The preparation of zirconia ceramic bearing rings typically involves powder metallurgy processes. The key steps include: first, mixing zirconia nanopowder, water, dispersant, and binder to prepare a uniform and stable ceramic slurry; then, obtaining a ceramic green body with a certain shape and strength through spray drying granulation and dry pressing techniques; finally, the green body needs to undergo degreasing and sintering processes to ultimately form a dense ceramic product.

[0004] In the aforementioned process chain, green body forming is a crucial link connecting the preceding and following stages, and the selection and performance of the binder are critical to the success or failure of this stage. The binder not only needs to ensure the rheological properties and stability of the slurry, but also directly determines the strength and flexibility (toughness) of the formed ceramic green body. If the green body has insufficient strength or excessive brittleness, it is prone to defects such as cracks during subsequent drying, handling, or machining, leading to a decrease in product yield.

[0005] Currently, acrylic resins are widely used as binders in this field. For example, Japanese Patent Publication No. JP2015202987A, published on November 16, 2015, discloses a binder for ceramic forming. The main advantage of this type of binder is its excellent thermal decomposition properties, allowing it to completely decompose and escape during the debinding process before sintering, thereby minimizing residual carbides and avoiding adverse effects on the final sintered body's properties. However, practice has shown that ceramic green bodies prepared using only acrylic resins as binders still have shortcomings in terms of strength and flexibility. The green bodies often exhibit high brittleness, making it difficult to withstand demolding stress or minor deformations during subsequent processing, resulting in a significant risk of cracking.

[0006] For example, Chinese patent CN1508209A, published on 2004-06-30, discloses a ceramic slurry composition in which a water-soluble acrylic binder is added to the slurry. The binder solid is obtained by copolymerizing alkyl acrylate and / or alkyl methacrylate with at least one unsaturated monomer containing a carboxyl group. However, it is not suitable for casting molding, has limitations for dry pressing molding, and is poor in terms of the strength and toughness of ceramic green bodies. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the above-mentioned defects of the prior art and provide a novel water-based adhesive for nano-ceramic molding that can impart high strength and high flexibility to ceramic green bodies, while maintaining excellent thermal decomposition characteristics and stable performance. The present invention also provides a method for preparing the water-based adhesive for nano-ceramic molding and provides specific applications of the water-based adhesive in nano-ceramic molding.

[0008] The water-based binder for nano-ceramic molding comprises the following raw materials, prepared in the following mass percentages: acrylic monomers, 20-30%; long-chain unsaturated carboxylic acids, 15-30%; hydroxyacrylamides, 2.5-4%; water-soluble plasticizers, 15-25%; unsaturated carboxylic acid vinyl esters, 0.5-2%; hydrophilic solvents, 25-35%; and initiators, 0.2-0.5%.

[0009] The acrylic monomers mentioned are one or more of methyl methacrylate, methyl acrylate, butyl acrylate, butyl methacrylate, and hydroxyethyl methacrylate.

[0010] The long-chain unsaturated carboxylic acid is polyethylene glycol monomethyl ether maleate, or a blend of polyethylene glycol monomethyl ether maleate and an unsaturated acid. The structural formula of polyethylene glycol monomethyl ether maleate is: Mn is 300~900 g / mol, where n is determined by the final molecular weight Mn; the unsaturated acid is methacrylic acid, acrylic acid, or itaconic acid. The specific preparation steps for maleic acid polyethylene glycol monomethyl ether ester are as follows: maleic anhydride and polyethylene glycol monomethyl ether are added to a reactor, along with a catalyst and a polymerization inhibitor, and the mixture is heated to react and obtain maleic acid polyethylene glycol monomethyl ether ester.

[0011] The hydroxyacrylamides are one or a mixture of two of N-hydroxymethylacrylamide and N-hydroxyethylacrylamide.

[0012] The water-soluble plasticizer is one or more of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, glycerin, and polyethylene glycol.

[0013] The unsaturated carboxylic acid vinyl ester is one or more of vinyl acetate, vinyl propionate, and vinyl butyrate.

[0014] The hydrophilic solvent is one or more of methanol, ethanol, isopropanol, acetone, butanone, and tetrahydrofuran.

[0015] The initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, azobiscyclohexylformitrile, benzoyl peroxide, and tert-butyl peroxide-2-ethylhexanoate.

[0016] The preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: mixing a water-soluble plasticizer and a hydrophilic solvent and heating to 70-90°C to obtain solution A; mixing an acrylic monomer, a long-chain unsaturated carboxylic acid, an unsaturated carboxylic acid vinyl ester, and an initiator to obtain solution B; preparing an aqueous solution of hydroxyacrylamide to obtain solution C; simultaneously adding solutions B and C dropwise (controlling the dropwise rate to ensure that the two solutions are added simultaneously) to solution A; after the dropwise addition is completed, maintaining the temperature for reaction; after the reaction solution is cooled, neutralizing; and removing the hydrophilic solvent under vacuum to obtain the water-based adhesive for nano-ceramic molding.

[0017] The application of the water-based binder in the nano-ceramic molding process involves adding the prepared water-based binder to ceramic slurry to prepare ceramic green bodies, ultimately yielding ceramic products. The ceramic raw materials are alumina, zirconium oxide, and titanium dioxide.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] (1) This invention successfully synthesizes a waterborne adhesive with both high strength and high flexibility by using maleic acid monomethyl ether ester with long polyethylene glycol side chains as the key functional monomer and copolymerizing it with other specific monomers (such as acrylic monomers, hydroxyacrylamide, and unsaturated vinyl carboxylic acid esters). The long side chain structure plays an "internal plasticizing" role in the polymer, effectively improving the flexibility and crack resistance of the green body. At the same time, because it is connected to the polymer backbone through chemical bonds, it fundamentally overcomes the problem of unstable green body performance caused by the easy volatility and migration of small molecule plasticizers in the prior art.

[0020] (2) This invention introduces hydroxyl groups and active crosslinking sites that can form hydrogen bonds into the polymer molecular chain by introducing hydroxyl acrylamide monomers and unsaturated vinyl carboxylic acids. This not only significantly enhances the room temperature strength (dry strength) of the green body, enabling it to withstand mechanical stress during subsequent processing, but also allows these groups to undergo crosslinking reactions when heated, further improving the strength of the green body in the early stage of degreasing. This ensures a smooth transition from degreasing to sintering, thereby significantly reducing the breakage rate of the green body and improving the product yield.

[0021] (3) The adhesive system of the present invention uses water as a medium and selects water-soluble plasticizers (such as polyethylene glycol, glycerin, etc.) and hydrophilic solvents to ensure excellent compatibility and dispersion stability of each component. The prepared adhesive has good compatibility with ceramic slurry and can form a uniform and stable slurry. At the same time, the polymer skeleton retains the excellent thermal decomposition characteristics of acrylic resins, and can completely and steadily decompose and escape during the degreasing process without residual carbides, avoiding adverse effects on the final sintered ceramic properties (such as color, density, and mechanical strength). Moreover, the entire system is environmentally friendly and safe to produce. Attached Figure Description

[0022] Figure 1 The TGA and DTG curves of the adhesive prepared in Example 1 are shown.

[0023] Figure 2 a is an optical microscope image (200x magnification) of the surface of a zirconia ceramic sintered product prepared using the binder prepared in Example 1 after polishing. Figure 2 b is an optical microscope image (200x magnification) of the surface of a zirconia ceramic sintered product made with traditional polyvinyl alcohol adhesive after polishing. Detailed Implementation

[0024] The present invention will be further described below with reference to specific embodiments.

[0025] Specifically, the preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: adding a water-soluble plasticizer and a hydrophilic solvent to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device; purging with nitrogen while simultaneously placing the four-necked flask in a constant temperature water bath and stirring to raise the temperature to 70-90°C to obtain solution A; weighing an acrylic monomer and a long-chain unsaturated carboxylic acid (polyethylene glycol monomethyl ether maleate, or a blend of polyethylene glycol monomethyl ether maleate and an unsaturated acid, wherein the structural formula of polyethylene glycol monomethyl ether maleate is: In a beaker, unsaturated vinyl carboxylic acid esters (Mn: 300~900 g / mol) were dissolved by adding an initiator and stirring to obtain solution B. Hydroxyacrylamides were prepared by adding water to make a 50 wt% aqueous solution of hydroxyacrylamides, which is solution C. Solutions B and C were added dropwise to solution A simultaneously for 2~5 h. After the addition was completed, the reaction was kept at 70~90℃ for 2~4 h. The reaction solution was cooled to below 60℃ and neutralized with ammonia water. The ammonia water addition time was controlled at 0.5~1 h. Then, stirring was continued for 0.5~1 h. The hydrophilic solvent was removed by vacuum distillation at 40~70℃ to obtain an aqueous binder for nano-ceramic molding.

[0026] Maleic acid monopolyethylene glycol monomethyl ether ester was prepared in-house. The specific preparation steps were as follows: Equimolar amounts of maleic anhydride and polyethylene glycol monomethyl ether (Mn: 200~800 g / mol) were added to a reactor, along with 1 wt% of the catalyst p-toluenesulfonic acid and 1 wt% of the polymerization inhibitor hydroquinone. The mixture was reacted at 100°C for 7 h to obtain maleic acid monopolyethylene glycol monomethyl ether ester.

[0027] Example 1

[0028] The preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: Add 28.5g of glycerol, 21.0g of polyethylene glycol (Mn~300g / mol), and 85.0g of isopropanol to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device; purge with nitrogen while simultaneously placing the four-necked flask in a constant temperature water bath and stirring to raise the temperature to 82℃ to obtain solution A; weigh out 33.0g of methyl acrylate, 10.5g of butyl acrylate, 3.0g of butyl methacrylate, 13.5g of methyl methacrylate, 3.0g of hydroxyethyl methacrylate, and 30g of polyethylene glycol monomethyl ether maleate (Mn~300g / mol). 0g of acrylic acid, 15.5g of acrylic acid, and 3.0g of vinyl acetate were placed in a beaker, and 1.1g of azobisisobutyronitrile was added and stirred to dissolve, resulting in solution B. 9.0g of N-hydroxymethylacrylamide was taken and water was added to prepare a 50wt% N-hydroxymethylacrylamide aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 4 hours. After the addition was completed, the reaction was maintained at 82℃ for 3 hours. The reaction solution was then cooled to below 60℃, and a mixture of 19.5g of ammonia and 151.3g of water was added dropwise over a period of 1 hour. The mixture was then stirred for another 0.5 hours. Isopropanol was removed by vacuum distillation at 50℃ to obtain an aqueous binder for nano-ceramic molding.

[0029] The TGA and DTG curves of the prepared binder are shown in the figure. Figure 1 As shown, from Figure 1 It can be seen that there is nearly 20% thermal weight loss before 300℃, which can avoid the generation of a large amount of gas in a short period of time due to concentrated thermal degradation, resulting in a large number of pores inside the ceramic product and thus a decrease in sintering strength. The thermal degradation behavior over a wide temperature range is more conducive to debinding and the formation of a dense internal structure.

[0030] Example 2

[0031] The preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: Adding 15.0g of ethylene glycol, 24.5g of diethylene glycol, 10.0g of isopropanol, and 55.0g of acetone to a four-necked flask equipped with a stirrer, thermometer (under nitrogen protection), and condenser (under cooling water), purging with nitrogen, and simultaneously placing the four-necked flask in a constant temperature water bath and stirring to raise the temperature to 85°C to obtain solution A; weighing 28.5g of methyl acrylate, 14.5g of methyl methacrylate, 15.5g of butyl acrylate, 2.0g of butyl methacrylate, 1.5g of hydroxyethyl methacrylate, 4.5g of vinyl propionate, and polyethylene glycol monomethyl ether maleate (… 50.0 g of Mn (498 g / mol) was placed in a beaker, and 1.0 g of azobisisobutyronitrile was added and stirred to dissolve, resulting in solution B. 7.5 g of N-hydroxyethylacrylamide was taken and water was added to prepare a 50 wt% N-hydroxyethylacrylamide aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 5 h. After the addition was completed, the reaction was kept at 78 °C for 2 h. The reaction solution was then cooled to below 60 °C, and a mixture of 17.5 g of ammonia and 146.3 g of water was added dropwise over a period of 1 h. The mixture was then stirred for another 0.5 h. Propanol and acetone were removed by vacuum distillation at 60 °C to obtain an aqueous binder for nano-ceramic molding.

[0032] Example 3

[0033] The preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: Adding 10.0g of polyethylene glycol (Mn~400g / mol), 39.5g of propylene glycol, 55.0g of isopropanol, and 30.0g of tetrahydrofuran to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device; purging with nitrogen while simultaneously placing the four-necked flask in a constant temperature water bath and stirring to raise the temperature to 72℃ to obtain solution A; weighing 25.5g of methyl acrylate, 11.5g of methyl methacrylate, 18.0g of butyl acrylate, 5.0g of butyl methacrylate, 4.5g of hydroxyethyl methacrylate, 2.0g of vinyl butyrate, and 698g of polyethylene glycol monomethyl ether maleate (Mn~698g). 35g of N-hydroxymethylacrylamide and 26.0g of itaconic acid were placed in a beaker, and 0.8g of benzoyl peroxide was added and stirred to dissolve, resulting in solution B. 4.0g and 5.0g of N-hydroxymethylacrylamide and N-hydroxyethylacrylamide were respectively added to water to prepare a 50wt% aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 3.5h. After the addition was completed, the reaction was maintained at 82℃ for 3.5h. The reaction solution was then cooled to below 60℃, and a mixture of 21.2g of ammonia and 142.6g of water was added dropwise over a period of 1h. The mixture was then stirred for another 0.5h. Isopropanol and tetrahydrofuran were removed by vacuum distillation at 45℃ to obtain an aqueous binder for nano-ceramic molding.

[0034] Example 4

[0035] The preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: Adding 7.5g of triethylene glycol, 15.0g of polyethylene glycol (Mn~400g / mol), 15.0g of methanol, and 61.5g of isopropanol to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device; purging with nitrogen while simultaneously placing the four-necked flask in a constant temperature water bath and stirring to raise the temperature to 76℃ to obtain solution A; weighing 38.0g of methyl acrylate, 8.5g of methyl methacrylate, 12.5g of butyl acrylate, 1.0g of butyl methacrylate, 5.0g of hydroxyethyl methacrylate, 1.0g of vinyl acetate, 2.0g of vinyl propionate, and polyethylene glycol monomethyl ether maleate (Mn~400g / mol). 45.0 g of N-hydroxymethylacrylamide (~498 g / mol) and 15.5 g of methacrylic acid were placed in a beaker, and 0.7 g of azodicyclohexylformonitrile was added and stirred to dissolve, resulting in solution B. 6.5 g of N-hydroxymethylacrylamide was taken and water was added to prepare a 50 wt% N-hydroxymethylacrylamide aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 4.5 h. After the addition was completed, the reaction was kept at 76 °C for 2.5 h. The reaction solution was then cooled to below 60 °C, and a mixture of 23.2 g of ammonia and 151.3 g of water was added dropwise over a period of 1 h. The mixture was then stirred for another 0.5 h. Isopropanol and methanol were removed by vacuum distillation at 50 °C to obtain a water-based binder for nano-ceramic molding.

[0036] Example 5

[0037] The preparation method of the water-based adhesive for nano-ceramic molding includes the following steps: Adding 28.1g of ethylene glycol, 15.0g of polyethylene glycol (Mn~400g / mol), 30.0g of ethanol, and 46.5g of isopropanol to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device; purging with nitrogen while simultaneously placing the four-necked flask in a constant temperature water bath and stirring to raise the temperature to 78℃ to obtain solution A; weighing 30.0g of methyl acrylate, 5.5g of methyl methacrylate, 20.5g of butyl acrylate, 4.0g of butyl methacrylate, 3.8g of hydroxyethyl methacrylate, 2.2g of vinyl acetate, 0.8g of vinyl butyrate, and polyethylene glycol monomethyl ether maleate (Mn~400g / mol)... 20.0 g of N-hydroxyethylacrylamide (~900 g / mol) and 16.3 g of acrylic acid were placed in a beaker, and 0.8 g of tert-butyl peroxide-2-ethylhexanoate was added and stirred to dissolve, resulting in solution B. 7.7 g of N-hydroxyethylacrylamide was taken and water was added to prepare a 50 wt% N-hydroxyethylacrylamide aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 3.5 h. After the addition was completed, the reaction was maintained at 76 °C for 3.5 h. The reaction solution was then cooled to below 60 °C, and a mixture of 22.2 g of ammonia and 182.8 g of water was added dropwise over a period of 1 h. The mixture was then stirred for another 0.5 h. Isopropanol and ethanol were removed by vacuum distillation at 55 °C to obtain an aqueous binder for nano-ceramic molding.

[0038] Comparative Example 1

[0039] The comparative example, without the addition of vinyl acetate, is prepared using the following steps: 28.5g of glycerol, 21.0g of polyethylene glycol (Mn~300g / mol), and 85.0g of isopropanol are added to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device. Nitrogen is purged, and the flask is simultaneously placed in a constant-temperature water bath and heated to 82℃ to obtain solution A. 33.0g of methyl acrylate, 10.5g of butyl acrylate, 3.0g of butyl methacrylate, 13.5g of methyl methacrylate, 3.0g of hydroxyethyl methacrylate, 30.0g of polyethylene glycol monomethyl ether maleate, and 15.5g of acrylic acid are weighed. Polyethylene glycol monomethyl ether ester (Mn ~ 328 g / mol) was dissolved in a beaker with 1.1 g of azobisisobutyronitrile (AIB) by stirring to obtain solution B. 9.0 g of N-hydroxymethylacrylamide was added to water to prepare a 50 wt% N-hydroxymethylacrylamide aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 4 hours. After the addition was complete, the reaction was maintained at 82°C for 3 hours. The reaction solution was then cooled to below 60°C, and a mixture of 19.5 g of ammonia and 151.3 g of water was added dropwise over a period of 1 hour. Stirring continued for 0.5 hours. Isopropanol was removed by vacuum distillation at 50°C to obtain an aqueous binder for nano-ceramic molding.

[0040] Comparative Example 2

[0041] The comparative example, without the addition of polyethylene glycol monomethyl ether maleate, is prepared using the following steps: 28.5 g of glycerol, 21.0 g of polyethylene glycol (Mn~300 g / mol), and 85.0 g of isopropanol are added to a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen purging device. Nitrogen is purged, and the flask is simultaneously placed in a constant temperature water bath and heated to 82°C to obtain solution A. 33.0 g of methyl acrylate, 10.5 g of butyl acrylate, 3.0 g of butyl methacrylate, 13.5 g of methyl methacrylate, 3.0 g of hydroxyethyl methacrylate, and 22.5 g of acrylic acid are weighed. 3.0 g of vinyl acetate was placed in a beaker, and 1.1 g of azobisisobutyronitrile was added and stirred to dissolve, resulting in solution B. 9.0 g of N-hydroxymethylacrylamide was taken and water was added to prepare a 50 wt% N-hydroxymethylacrylamide aqueous solution, which is solution C. Solutions B and C were simultaneously added dropwise to solution A over a period of 4 hours. After the addition was completed, the reaction was maintained at 82°C for 3 hours. The reaction solution was then cooled to below 60°C, and a mixture of 19.5 g of ammonia and 151.3 g of water was added dropwise over a period of 1 hour. The mixture was then stirred for another 0.5 hours. Isopropanol was removed by vacuum distillation at 50°C to obtain an aqueous binder for nano-ceramic molding.

[0042] (1) Application:

[0043] The binders prepared in the above examples and comparative examples were used to prepare zirconia ceramic products. The specific steps were as follows: Zirconia ceramic slurry (yttrium-stabilized zirconia, solid content 50-60%, pH 8-12) was dispersed for at least 30 minutes; the prepared aqueous binder was added and stirred for 40 minutes; a release agent (SELOSOL 920 from Chukyo Oils & Fats Co., Ltd.) was added and stirred for 10 minutes; spray granulation was then performed, followed by sieving through an 80-mesh sieve. After cooling, the compressibility of the granulated powder was evaluated, and the performance of the ceramic green body was tested. The prepared zirconia ceramic green body was degreased and sintered at 1450℃ to obtain sintered zirconia ceramic products. The green body strength and flexural strength test standards were GB / T6569-2006 (three-point bending).

[0044] The performance of the ceramic green bodies and zirconia ceramic products used in the above applications was tested, and the test results are shown in Table 1.

[0045] Table 1 Test Results

[0046]

[0047] (2) An optical microscope image (magnified 200x) of the surface of the zirconia ceramic sintered product prepared in Example 1 above after polishing. Figure 2 As shown in a, Figure 2b is an optical microscope image (200x magnification) of the surface of a zirconia ceramic sintered product prepared using a traditional polyvinyl alcohol binder after polishing. The product was prepared according to the following steps: Zirconia ceramic slurry (yttrium-stabilized zirconia, solid content 50-60%, pH 8-12) was dispersed for at least 30 minutes; polyvinyl alcohol binder was added and stirred for 40 minutes; a release agent (SELOSOL 920 from Chukyo Oils & Fats Co., Ltd.) was added and stirred for 10 minutes; spray granulation was performed; the slurry was then sieved through an 80-mesh screen; after cooling, a ceramic green body was obtained; the green body was then degreased and sintered at 1450℃ to obtain the zirconia ceramic sintered product. Figure 2 A comparison of a and b shows that the adhesive prepared by Example 1 has better debonding performance, a denser internal structure, and significantly fewer pores.

Claims

1. A water-based adhesive for nano-ceramic molding, characterized in that: It is prepared from the following raw materials in the following mass percentages: acrylic monomers, 20-30%; long-chain unsaturated carboxylic acids, 15-30%; N-hydroxymethylacrylamide and / or N-hydroxyethylacrylamide, 2.5-4%; water-soluble plasticizer, 15-25%; unsaturated carboxylic acid vinyl esters, 0.5-2%; hydrophilic solvent, 25-35%; initiator, 0.2-0.5%. The long-chain unsaturated carboxylic acid is polyethylene glycol monomethyl ether maleate, or a blend of polyethylene glycol monomethyl ether maleate and an unsaturated acid. The structural formula of polyethylene glycol monomethyl ether maleate is: Mn is 300~900 g / mol; the unsaturated acid is methacrylic acid, acrylic acid or itaconic acid; the unsaturated carboxylic acid vinyl ester is one or more of vinyl acetate, vinyl propionate and vinyl butyrate.

2. The aqueous adhesive for nano-ceramic molding according to claim 1, characterized in that: The acrylic monomers mentioned are two or more of methyl methacrylate, methyl acrylate, butyl acrylate, butyl methacrylate, and hydroxyethyl methacrylate.

3. The aqueous adhesive for nano-ceramic molding according to claim 1, characterized in that: The water-soluble plasticizer is one or more of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, glycerin, and polyethylene glycol.

4. The aqueous adhesive for nano-ceramic molding according to claim 1, characterized in that: The hydrophilic solvent is one or more of methanol, ethanol, isopropanol, acetone, butanone, and tetrahydrofuran.

5. The aqueous adhesive for nano-ceramic molding according to claim 1, characterized in that: The initiator is one of azobisisobutyronitrile, azobisisoheptanenitrile, azobiscyclohexylformitrile, benzoyl peroxide, and tert-butyl peroxide-2-ethylhexanoate.

6. A method for preparing the aqueous binder for nano-ceramic molding according to any one of claims 1-5, characterized in that: Includes the following steps: A solution A is obtained by mixing a water-soluble plasticizer and a hydrophilic solvent and heating the mixture to 70-90°C. An acrylic monomer, a long-chain unsaturated carboxylic acid, an unsaturated carboxylic acid vinyl ester, and an initiator are mixed to obtain a solution B. A hydroxyacrylamide aqueous solution is prepared as solution C. Solutions B and C are simultaneously added dropwise to solution A. After the addition is complete, the reaction is maintained at a constant temperature. The reaction solution is then cooled and neutralized. The hydrophilic solvent is removed under vacuum to obtain an aqueous adhesive for nano-ceramic molding.

7. The application of an aqueous adhesive for nano-ceramic molding according to any one of claims 1-5, characterized in that: The prepared water-based binder is added to the ceramic slurry to prepare ceramic green bodies, and finally ceramic products are obtained.

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