High-temperature-resistant environment-friendly household ceramic and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant environment-friendly household ceramic and a preparation method thereof, and relates to the technical field of ceramics, and the ceramic is prepared from the following components in parts by weight: 12-24 parts of kaolin, 6-12 parts of aluminum oxide, 4-10 parts of silicon dioxide, 4-7 parts of magnesium oxide, 3-6 parts of a carbon fiber / boron nitride composite material, 2-5 parts of titanium dioxide and 2-5 parts of zirconium oxide. According to the invention, through a unique composite reinforcement technology and a preparation process, the ceramic is endowed with excellent comprehensive performance, the whole product has excellent mechanical strength, high temperature resistance and excellent thermal shock resistance stability, can cope with harsh cold and hot impact, is compact and uniform in structure and stable and reliable in performance, and significantly improves the overall quality of the product.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramics, and in particular to a high-temperature resistant and environmentally friendly household ceramic and a preparation method thereof. Background Art

[0002] Ceramic materials are widely used in household applications such as tableware and cookware due to their stable chemical properties, high temperature resistance, high hardness, and non-toxic and environmentally friendly properties. However, traditional household ceramics are mostly single-phase or simple multi-phase inorganic non-metallic materials. Their inherent brittleness and poor thermal shock resistance limit their application scenarios. For example, ordinary ceramic cookware is very likely to crack and damage due to the internal stress generated by the huge temperature gradient when it is directly rinsed after being heated on the stove, or when it is taken out of the refrigerator and heated immediately. In addition, bumps and collisions during daily use can easily cause ceramic products to become chipped or broken, affecting their appearance and service life.

[0003] To improve the toughness and thermal shock resistance of ceramics, a major technical direction is to introduce a reinforcing phase into the ceramic matrix to prepare ceramic-based composites. Carbon fiber, due to its high strength, high modulus, low density, and excellent mechanical properties, is an ideal reinforcing and toughening agent. Hexagonal boron nitride, known for its high thermal conductivity, low thermal expansion coefficient, excellent chemical stability, and high-temperature lubricity, is an ideal filler for improving the thermal shock resistance of materials. In theory, the co-introduction of carbon fiber and boron nitride into a ceramic matrix is expected to synergistically improve the overall performance of the ceramic.

[0004] CN105174968A discloses a high-hardness boron nitride ceramic and a preparation method thereof. The ceramic is made from the following raw materials in parts by weight: 85-115 parts of boron nitride, 1-6 parts of aluminum oxide, 2-7 parts of kaolin powder, 0.6-2 parts of zirconium oxide powder, 1.5-4 parts of calcium oxide powder, 2-6 parts of titanium dioxide powder, 1.5-3.5 parts of antimony trioxide powder, 0.6-3 parts of carbon fiber, 0.05-0.3 parts of surfactant, 0.5-3 parts of polyethylene, 20-30 parts of anhydrous ethanol, 2-5 parts of glycerol, and 65-75 parts of deionized water.

[0005] However, in practical applications, this technical route faces huge challenges. First, the surface chemical properties of carbon fiber are inert, and its wettability and compatibility with the inorganic ceramic matrix are extremely poor, resulting in very weak interfacial bonding between the two. The load cannot be effectively transferred from the matrix to the fiber, and the reinforcing effect of the fiber is greatly reduced. It is even easy to cause interfacial debonding, which becomes a source of material defects. Secondly, the carbon fiber itself has a large specific surface area and is prone to agglomeration. It is difficult to achieve uniform dispersion in the ceramic matrix. The agglomerated fibers will become stress concentration points, which will reduce the mechanical properties and reliability of the product. Thirdly, during the high-temperature sintering process required for ceramics, carbon fiber is easily oxidized, causing its reinforcing effect to fail.

[0006] Therefore, how to effectively modify the surface of carbon fiber and boron nitride, construct a stable and strongly bonded interface transition layer, and achieve uniform dispersion of the reinforcement in the ceramic matrix to fully exert its role in strengthening toughness and improving thermal shock resistance is a technical problem that needs to be urgently solved in the current field of high-performance household ceramics. Summary of the Invention

[0007] In order to address the deficiencies in the prior art, the purpose of the present invention is to provide a high-temperature resistant and environmentally friendly household ceramic and a preparation method thereof. The present invention imparts excellent comprehensive performance to the ceramic through unique composite reinforcement technology and preparation process. The product as a whole has excellent mechanical strength, high-temperature resistance and outstanding thermal shock stability, and can cope with severe cold and hot shocks. Its structure is dense and uniform, and its performance is stable and reliable, which significantly improves the overall quality of the product.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions: A high-temperature resistant and environmentally friendly household ceramic is made from the following components, measured by weight: 12-24 parts of kaolin, 6-12 parts of aluminum oxide, 4-10 parts of silicon dioxide, 4-7 parts of magnesium oxide, 3-6 parts of carbon fiber / boron nitride composite, 2-5 parts of titanium dioxide, and 2-5 parts of zirconium oxide.

[0009] Preferably, the carbon fiber / boron nitride composite is prepared by the following method steps: (1) Dispersing carbon fibers in acetone, ultrasonically treating, drying, and then dispersing in a dopamine hydrochloride aqueous solution, adjusting the pH, stirring the reaction, filtering, washing, and drying the product to obtain functionalized carbon fibers; Preparation of functionalized carbon fibers: In a weakly alkaline aqueous solution, dopamine molecules undergo a series of reactions, including oxidation, intermolecular addition, and crosslinking, leading to self-polymerization and the formation of an ultra-thin and robust PDA film on the carbon fiber surface. This film is rich in hydroxyl and amine / imine groups from catechol, providing numerous active sites for subsequent grafting reactions.

[0010] Preferably, in step (1), the ratio of carbon fiber, acetone, and dopamine hydrochloride aqueous solution is 10 g: 200-300 mL: 400-600 mL; and the concentration of the dopamine hydrochloride aqueous solution is 1-3 mg / mL.

[0011] Preferably, in step (1), ultrasonic treatment is performed for 30 to 60 minutes; the pH is adjusted to 8.0 to 9.0 with Tris buffer; and the stirring reaction conditions are 20 to 35° C. and 12 to 24 hours.

[0012] (2) Dispersing the functionalized carbon fiber and the monoepoxy POSS in DMF, ultrasonically treating the mixture, stirring the mixture under a nitrogen atmosphere, filtering, washing, and drying the product to obtain the modified carbon fiber; Preparation of modified carbon fiber: On the PDA layer formed in the first step, a large amount of amino Acting as nucleophiles, they attack the epoxy ring on the monoepoxy POSS molecule, causing the epoxy ring to open and form a stable carbon-nitrogen (CN) covalent bond, thereby firmly "anchoring" the POSS molecule to the carbon fiber surface. At the same time, the ring-opening reaction will also generate a new hydroxyl group next to it.

[0013] Preferably, in step (2), the usage ratio of the functionalized carbon fiber, the monoepoxy POSS, and the DMF is 10 g: 10-28 g: 250-400 mL.

[0014] Preferably, in step (2), the ultrasonic treatment is carried out for 30 to 60 minutes; and the stirring reaction conditions are 75 to 90° C. and the stirring reaction is carried out for 12 to 24 hours.

[0015] (3) ball-milling boron nitride to obtain hydroxylated boron nitride, then dispersing the hydroxylated boron nitride in a polyacrylic acid ethanol solution, ultrasonically treating the solution, and spray-drying the solution to obtain modified boron nitride; Preparation of modified boron nitride: First, through the mechanochemical force of high-energy ball milling, defects and dangling bonds are created at the edges of the inert boron nitride (BN) lattice. These highly active sites react with water molecules in the air, forming hydroxyl (-OH) groups on the BN surface. Subsequently, when the hydroxylated BN is dispersed in a polyacrylic acid (PAA) solution, multiple hydrogen bonds form between the hydroxyl groups on the BN surface and the numerous carboxyl (-COOH) groups on the PAA molecular chains. Finally, a spray drying process rapidly removes the solvent, allowing the PAA to form a stable, carboxyl-rich shell as a physical coating.

[0016] Preferably, in step (3), the ball milling conditions are ball milling at 300-500 r / min in a zirconia ball mill jar of a planetary ball mill for 12-36 hours; the ultrasonic treatment time is 60-120 minutes; the spray drying inlet temperature is 160-170°C, and the outlet temperature is 70-80°C.

[0017] Preferably, in step (3), the usage ratio of hydroxylated boron nitride and polyacrylic acid ethanol solution is 10 g: 250-400 mL; and the concentration of the polyacrylic acid ethanol solution is 0.25-1 wt %.

[0018] (4) The modified boron nitride was dispersed in DMF, ultrasonically treated, EDC and NHS were added, and the mixture was stirred for activation. Then, the modified carbon fiber was added and the mixture was stirred for reaction under a nitrogen atmosphere. The product was filtered, washed, and dried to obtain a carbon fiber / boron nitride composite.

[0019] Preparation of composite materials: EDC acts as a dehydrating agent to react with the carboxyl groups on the surface of modified boron nitride to form an O-acylisourea intermediate, which is then captured by NHS to generate NHS active ester. The amino and hydroxyl groups on the surface of the modified carbon fiber act as nucleophiles to attack the NHS active ester to form an amide bond (-CO-NH-) and an ester bond (-CO-O-), thereby building a covalent bridge between the carbon fiber and boron nitride and achieving a strong composite between the two.

[0020] Preferably, in step (4), the amount ratio of modified boron nitride, DMF, EDC, NHS, and modified carbon fiber is 10 g: 300-500 mL: 2-5 g: 1-3 g: 3-6 g; ultrasonic treatment is performed for 30-60 min; and the stirring reaction conditions are stirring reaction at 30-60 ° C for 8-14 h.

[0021] The present invention also claims protection for a preparation method for the high-temperature resistant and environmentally friendly household ceramics, comprising the following steps: dispersing the components in ethanol, ultrasonically treating for 30 to 60 minutes to uniformly mix, removing ethanol, placing the mixture into a mold, pre-tightening for 10 to 12 seconds at 7.8 to 8.2 MPa, and then cold-pressing for 7 to 9 minutes at 34 to 36 MPa to obtain a ceramic green body; placing the ceramic green body in a sintering furnace, heating to 860 to 900°C at a rate of 6 to 7°C / min under a nitrogen atmosphere, keeping the temperature for 22 to 28 minutes, then heating to 1550 to 1600°C at a rate of 1.5 to 2.5°C / min, keeping the temperature for 2 to 3 hours, and naturally cooling to obtain the high-temperature resistant and environmentally friendly household ceramics.

[0022] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides a high-temperature resistant and environmentally friendly household ceramic. Kaolin serves as the basic skeleton to ensure plasticity and formability; alumina and silica serve as the main heat-resistant and reinforcing phases, giving the ceramic excellent high-temperature structural stability and basic strength; magnesium oxide serves as an efficient flux, which can reduce the sintering temperature and improve thermal shock resistance; zirconium oxide significantly improves the fracture toughness and strength of the ceramic through the phase change toughening mechanism; carbon fiber / boron nitride composite serves as the core reinforcing phase, giving the ceramic excellent mechanical properties and thermal shock resistance; titanium dioxide gives the ceramic a white and beautiful appearance and a certain self-cleaning and environmentally friendly function.

[0023] 2. The present invention provides a carbon fiber / boron nitride composite material. First, polydopamine is coated on the surface of the carbon fiber, which not only introduces a large number of active functional groups, but also enhances the dispersion performance of the carbon fiber, avoids the defects caused by fiber agglomeration, and improves the interface bonding strength between the fiber and the ceramic matrix. Secondly, the grafted polysilsesquioxane (POSS) will be converted into in situ during the subsequent high-temperature sintering. , SiC and other nano-ceramic structures, and tightly adhere to the surface of carbon fiber to form a high-temperature resistant and antioxidant "ceramic interface layer", which significantly improves the compressive strength and high-temperature stability of carbon fiber. Finally, the modified carbon fiber and modified boron nitride are cross-linked through chemical coupling to form a stable three-dimensional cross-linked network structure at the microscopic level, which improves the homogeneity of the filler in the matrix, can play a skeleton support role during the sintering process, and become an efficient path for stress transfer and heat conduction. Therefore, this design can maximize the excellent reinforcing and toughening effect of carbon fiber. In this composite material, carbon fiber contributes to the reinforcing and toughening effect, while boron nitride gives the ceramic thermal conductivity and thermal shock resistance. Ultimately, the comprehensive performance of ceramic products in terms of toughness, strength, high-temperature oxidation resistance and structural stability is comprehensively improved. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the embodiments. Of course, the specific embodiments described here are only used to explain the present invention and are not used to limit the present invention.

[0025] Unless otherwise specified, the chemical reagents and materials in the present invention are purchased from commercial sources or synthesized from commercially purchased raw materials.

[0026] Polyacrylic acid resin, purchased from Mitsubishi, Japan, brand BR-116.

[0027] The general structural formula of monoepoxy POSS is shown below:

[0028] Wherein, R is one of isooctyl, isobutyl and phenyl.

[0029] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 200-300 mL of acetone, ultrasonically treat for 30-60 min, dry and disperse in 400-600 mL of 1-3 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.0-9.0 with Tris buffer, stir and react at 20-35 °C for 12-24 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) Disperse 10 g of functionalized carbon fiber and 10-28 g of monoepoxy POSS in 250-400 mL of DMF, ultrasonicate for 30-60 min, stir and react at 75-90 °C in a nitrogen atmosphere for 12-24 h, filter, wash and dry the product to obtain modified carbon fiber; (3) The boron nitride was ball-milled in a zirconia ball mill of a planetary ball mill at 300-500 r / min for 12-36 h to obtain hydroxylated boron nitride. Then, 10 g of hydroxylated boron nitride was dispersed in 250-400 mL of a 0.25-1 wt% polyacrylic acid ethanol solution, ultrasonicated for 60-120 min, and spray-dried at an inlet temperature of 160-170 °C and an outlet temperature of 70-80 °C to obtain modified boron nitride. (4) Disperse 10 g of modified boron nitride in 300-500 mL of DMF, ultrasonicate for 30-60 min, add 2-5 g of EDC and 1-3 g of NHS, stir and activate, then add 3-6 g of modified carbon fiber, stir and react at 30-60 °C in a nitrogen atmosphere for 8-14 h, filter, wash and dry the product to obtain a carbon fiber / boron nitride composite; (5) 12-24 parts of kaolin, 6-12 parts of alumina, 4-10 parts of silica, 4-7 parts of magnesium oxide, 3-6 parts of carbon fiber / boron nitride composite, 2-5 parts of titanium dioxide, and 2-5 parts of zirconium oxide are dispersed in ethanol, ultrasonically treated for 30-60 minutes to mix evenly, and the ethanol is evaporated at 60°C to remove the ethanol. The mixture is placed in a mold, pre-tightened at 7.8-8.2 MPa for 10-12 seconds, and then cold-pressed at 34-36 MPa for 7-9 minutes to obtain a ceramic body; the ceramic body is placed in a sintering furnace, heated to 860-900°C at a rate of 6-7°C / min in a nitrogen atmosphere, kept warm for 22-28 minutes, then heated to 1550-1600°C at a rate of 1.5-2.5°C / min, kept warm for 2-3 hours, and naturally cooled to obtain the high-temperature resistant and environmentally friendly household ceramic.

[0030] The present invention will be further described below with reference to specific examples. Example 1

[0031] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 35 °C for 12 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) 10 g of functionalized carbon fiber and 28 g of monoepoxy POSS were dispersed in 300 mL of DMF, ultrasonically treated for 45 min, stirred and reacted at 90 °C under nitrogen atmosphere for 12 h, and the product was filtered, washed, and dried to obtain modified carbon fiber; (3) Boron nitride was ball-milled in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride. Then, 10 g of hydroxylated boron nitride was dispersed in 300 mL of a 0.5 wt% polyacrylic acid ethanol solution, ultrasonicated for 90 min, and spray-dried at an inlet temperature of 165 °C and an outlet temperature of 75 °C to obtain modified boron nitride. (4) Disperse 10 g of modified boron nitride in 400 mL of DMF, ultrasonicate for 45 min, add 5 g of EDC and 3 g of NHS, stir and activate, then add 6 g of modified carbon fiber, stir and react at 60 °C in a nitrogen atmosphere for 8 h, filter, wash and dry the product to obtain a carbon fiber / boron nitride composite; (5) 2400 g of kaolin, 1200 g of alumina, 1000 g of silica, 700 g of magnesium oxide, 600 g of carbon fiber / boron nitride composite, 500 g of titanium dioxide, and 500 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to mix evenly. The ethanol was evaporated at 60 °C, and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds, and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace, heated to 880 °C at a rate of 6.5 °C / min in a nitrogen atmosphere, kept warm for 25 min, and then heated to 1580 °C at a rate of 2.0 °C / min, kept warm for 2.5 hours, and naturally cooled to obtain the high-temperature resistant and environmentally friendly household ceramic. Example 2

[0032] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 30 ° C for 16 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) 10 g of functionalized carbon fiber and 22 g of monoepoxy POSS were dispersed in 300 mL of DMF, ultrasonically treated for 45 min, stirred and reacted at 85 °C under nitrogen atmosphere for 16 h, and the product was filtered, washed, and dried to obtain modified carbon fiber; (3) Boron nitride was ball-milled in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride. Then, 10 g of hydroxylated boron nitride was dispersed in 300 mL of a 0.5 wt% polyacrylic acid ethanol solution, ultrasonicated for 90 min, and spray-dried at an inlet temperature of 165 °C and an outlet temperature of 75 °C to obtain modified boron nitride. (4) Disperse 10 g of modified boron nitride in 400 mL of DMF, ultrasonicate for 45 min, add 4 g of EDC and 2 g of NHS, stir and activate, then add 5 g of modified carbon fiber, stir and react at 50 °C in a nitrogen atmosphere for 10 h, filter, wash and dry the product to obtain a carbon fiber / boron nitride composite; (5) 2000 g of kaolin, 1000 g of alumina, 800 g of silica, 600 g of magnesium oxide, 500 g of carbon fiber / boron nitride composite, 400 g of titanium dioxide, and 400 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to mix evenly. The ethanol was evaporated at 60 ° C and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace, heated to 880 ° C at a rate of 6.5 ° C / min in a nitrogen atmosphere, kept warm for 25 minutes, then heated to 1580 ° C at a rate of 2.0 ° C / min, kept warm for 2.5 hours, and naturally cooled to obtain the high-temperature resistant and environmentally friendly household ceramic. Example 3

[0033] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 25 °C for 20 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) 10 g of functionalized carbon fiber and 16 g of monoepoxy POSS were dispersed in 300 mL of DMF, ultrasonically treated for 45 min, stirred and reacted at 80 °C under nitrogen atmosphere for 20 h, and the product was filtered, washed, and dried to obtain modified carbon fiber; (3) Boron nitride was ball-milled in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride. Then, 10 g of hydroxylated boron nitride was dispersed in 300 mL of a 0.5 wt% polyacrylic acid ethanol solution, ultrasonicated for 90 min, and spray-dried at an inlet temperature of 165 °C and an outlet temperature of 75 °C to obtain modified boron nitride. (4) Disperse 10 g of modified boron nitride in 400 mL of DMF, ultrasonicate for 45 min, add 3 g of EDC and 2 g of NHS, stir and activate, then add 4 g of modified carbon fiber, stir and react at 40 °C in a nitrogen atmosphere for 12 h, filter, wash and dry the product to obtain a carbon fiber / boron nitride composite; (5) 1600 g of kaolin, 800 g of alumina, 600 g of silica, 500 g of magnesium oxide, 400 g of carbon fiber / boron nitride composite, 300 g of titanium dioxide, and 300 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to mix evenly. The ethanol was evaporated at 60 ° C and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace and heated to 880 ° C at a rate of 6.5 ° C / min in a nitrogen atmosphere. The temperature was kept at this temperature for 25 minutes, and then heated to 1580 ° C at a rate of 2.0 ° C / min. The temperature was kept at this temperature for 2.5 hours and cooled naturally to obtain the high-temperature resistant and environmentally friendly household ceramic. Example 4

[0034] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 20 °C for 24 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) 10 g of functionalized carbon fiber and 28 g of monoepoxy POSS were dispersed in 300 mL of DMF, ultrasonically treated for 45 min, stirred and reacted at 90 °C under nitrogen atmosphere for 12 h, and the product was filtered, washed, and dried to obtain modified carbon fiber; (3) Boron nitride was ball-milled in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride. Then, 10 g of hydroxylated boron nitride was dispersed in 300 mL of a 0.5 wt% polyacrylic acid ethanol solution, ultrasonicated for 90 min, and spray-dried at an inlet temperature of 165 °C and an outlet temperature of 75 °C to obtain modified boron nitride. (4) Disperse 10 g of modified boron nitride in 400 mL of DMF, ultrasonicate for 45 min, add 2 g of EDC and 1 g of NHS, stir and activate, then add 3 g of modified carbon fiber, stir and react at 30 °C in a nitrogen atmosphere for 14 h, filter, wash and dry the product to obtain a carbon fiber / boron nitride composite; (5) 1200 g of kaolin, 600 g of alumina, 400 g of silica, 400 g of magnesium oxide, 300 g of carbon fiber / boron nitride composite, 200 g of titanium dioxide, and 200 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to mix evenly. The ethanol was evaporated at 60 ° C, and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace, heated to 880 ° C at a rate of 6.5 ° C / min in a nitrogen atmosphere, kept warm for 25 minutes, and then heated to 1580 ° C at a rate of 2.0 ° C / min, kept warm for 2.5 hours, and naturally cooled to obtain the high-temperature resistant and environmentally friendly household ceramic. Comparative Example 1

[0035] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 35 °C for 12 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) Boron nitride was ball-milled in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride. Then, 10 g of hydroxylated boron nitride was dispersed in 300 mL of a 0.5 wt% polyacrylic acid ethanol solution, ultrasonicated for 90 min, and spray-dried at an inlet temperature of 165 °C and an outlet temperature of 75 °C to obtain modified boron nitride. (3) Disperse 10 g of modified boron nitride in 400 mL of DMF, ultrasonicate for 45 min, add 5 g of EDC and 3 g of NHS, stir and activate, then add 6 g of functionalized carbon fiber, stir and react at 60 °C in a nitrogen atmosphere for 8 h, filter, wash and dry the product to obtain a carbon fiber / boron nitride composite; (4) 2400 g of kaolin, 1200 g of alumina, 1000 g of silica, 700 g of magnesium oxide, 600 g of carbon fiber / boron nitride composite, 500 g of titanium dioxide, and 500 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to mix evenly. The ethanol was evaporated at 60 ° C and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace and heated to 880 ° C at a rate of 6.5 ° C / min in a nitrogen atmosphere. The temperature was kept at this temperature for 25 minutes, and then heated to 1580 ° C at a rate of 2.0 ° C / min. The temperature was kept at this temperature for 2.5 hours and cooled naturally to obtain the high-temperature resistant and environmentally friendly household ceramic. Comparative Example 2

[0036] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 35 °C for 12 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) 10 g of functionalized carbon fiber and 28 g of monoepoxy POSS were dispersed in 300 mL of DMF, ultrasonically treated for 45 min, stirred and reacted at 90 °C under nitrogen atmosphere for 12 h, and the product was filtered, washed, and dried to obtain modified carbon fiber; (3) ball milling the boron nitride in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride; (4) 2400 g of kaolin, 1200 g of alumina, 1000 g of silica, 700 g of magnesium oxide, 375 g of hydroxylated boron nitride, 225 g of modified carbon fiber, 500 g of titanium dioxide, and 500 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to make the mixture uniform. The ethanol was evaporated at 60 ° C and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace and heated to 880 ° C at a rate of 6.5 ° C / min in a nitrogen atmosphere. The temperature was kept at this temperature for 25 minutes, and then heated to 1580 ° C at a rate of 2.0 ° C / min. The temperature was kept at this temperature for 2.5 hours and naturally cooled to obtain the high-temperature resistant and environmentally friendly household ceramic. Comparative Example 3

[0037] A method for preparing high-temperature resistant and environmentally friendly household ceramics comprises the following steps: (1) Disperse 10 g of carbon fiber in 250 mL of acetone, ultrasonically treat for 45 min, remove and dry, then disperse in 500 mL of 2 mg / mL dopamine hydrochloride aqueous solution, adjust the pH to 8.5 with Tris buffer, stir and react at 35 °C for 12 h, filter, wash and dry the product to obtain functionalized carbon fiber; (2) ball milling the boron nitride in a zirconia ball mill of a planetary ball mill at 400 r / min for 24 h to obtain hydroxylated boron nitride; (3) 2400 g of kaolin, 1200 g of alumina, 1000 g of silica, 700 g of magnesium oxide, 375 g of hydroxylated boron nitride, 225 g of functionalized carbon fiber, 500 g of titanium dioxide, and 500 g of zirconium oxide were dispersed in 50 L of ethanol, and ultrasonically treated for 45 min to mix evenly. The ethanol was evaporated at 60 ° C and the mixture was placed in a mold. It was pre-tightened at 8.0 MPa for 11 seconds and then cold-pressed at 35 MPa for 8 minutes to obtain a ceramic body. The ceramic body was placed in a sintering furnace and heated to 880 ° C at a rate of 6.5 ° C / min in a nitrogen atmosphere. The temperature was kept at this temperature for 25 minutes, and then heated to 1580 ° C at a rate of 2.0 ° C / min. The temperature was kept at this temperature for 2.5 hours and cooled naturally to obtain the high-temperature resistant and environmentally friendly household ceramic.

[0038] In the embodiment, carbon fibers are modified with dopamine to obtain functionalized carbon fibers, which are then grafted with monoepoxy POSS to obtain modified carbon fibers; boron nitride is ball-milled to obtain hydroxylated boron nitride, which is then modified with polyacrylic acid to obtain modified boron nitride; the modified boron nitride is composited with the modified carbon fibers to obtain a carbon fiber / boron nitride composite; and finally, the carbon fiber / boron nitride composite is added to a ceramic matrix.

[0039] In Comparative Example 1, carbon fibers were modified with dopamine to obtain functionalized carbon fibers; boron nitride was ball-milled to obtain hydroxylated boron nitride, which was then modified with polyacrylic acid to obtain modified boron nitride; the modified boron nitride was composited with the functionalized carbon fibers to obtain a carbon fiber / boron nitride composite; and finally, the carbon fiber / boron nitride composite was added to a ceramic matrix. This differs from Example 1 in that the functionalized carbon fibers were not modified with monoepoxy POSS.

[0040] In Comparative Example 2, carbon fibers were modified with dopamine to obtain functionalized carbon fibers, which were then grafted with monoepoxy POSS to obtain modified carbon fibers. Boron nitride was ball-milled to obtain hydroxylated boron nitride. The modified carbon fibers and hydroxylated boron nitride were then directly added to a ceramic matrix. This differed from Example 2 in that the hydroxylated boron nitride was not modified with polyacrylic acid (and thus could not be composited with the modified carbon fibers).

[0041] In Comparative Example 3, carbon fibers were modified with dopamine to obtain functionalized carbon fibers; boron nitride was ball-milled to obtain hydroxylated boron nitride; and the functionalized carbon fibers and hydroxylated boron nitride were directly added to the ceramic matrix. This differs from Example 3 in that the functionalized carbon fibers and hydroxylated boron nitride were not modified.

[0042] The ceramics prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were subjected to performance tests. The gloss, lead dissolution, and chromium dissolution of the ceramics were tested with reference to GB / T 3532-2022 "Daily-use Porcelain". The temperature gradient of 20°C was used as the temperature difference gradient. The difference between the highest heating temperature at which the sample was not damaged and the room temperature (20°C) was recorded as the index of its thermal shock resistance in °C, and the average value of 5 samples was taken. The total number of "pressure-insulation" cycles that each sample could withstand before the first glaze crack appeared was recorded with reference to GB / T 34252-2017 "Test method for glaze crack resistance of daily-use ceramics" as its crack resistance index, and the average value of 5 samples was taken. The fracture toughness was tested with reference to GB / T 23806-2009 "Test method for fracture toughness of fine ceramics - single-edge pre-cracked beam (SEPB) method". The fracture toughness was tested with reference to GB / T 23805-2009 "Test Method for Tensile Strength of Fine Ceramics at Room Temperature". Specific data are shown in Table 1.

[0043] Table 1 Ceramic performance test results

[0044] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A high temperature resistant and environmentally friendly household ceramic, characterized in that: The invention is prepared from the following components in parts by weight: 12-24 parts of kaolin, 6-12 parts of aluminum oxide, 4-10 parts of silicon dioxide, 4-7 parts of magnesium oxide, 3-6 parts of carbon fiber / boron nitride composite, 2-5 parts of titanium dioxide and 2-5 parts of zirconium oxide.

2. The high temperature resistant and environmentally friendly household ceramic according to claim 1, characterized in that: The carbon fiber / boron nitride composite is prepared by the following method steps: (1) Dispersing carbon fibers in acetone, ultrasonically treating, drying, and then dispersing in a dopamine hydrochloride aqueous solution, adjusting the pH, stirring the reaction, filtering, washing, and drying the product to obtain functionalized carbon fibers; (2) Dispersing the functionalized carbon fiber and the monoepoxy POSS in DMF, ultrasonically treating the mixture, stirring the mixture under a nitrogen atmosphere, filtering, washing, and drying the product to obtain the modified carbon fiber; (3) ball-milling boron nitride to obtain hydroxylated boron nitride, then dispersing the hydroxylated boron nitride in a polyacrylic acid ethanol solution, ultrasonically treating the solution, and spray-drying the solution to obtain modified boron nitride; (4) The modified boron nitride was dispersed in DMF, ultrasonically treated, EDC and NHS were added, and the mixture was stirred for activation. Then, the modified carbon fiber was added and the mixture was stirred for reaction under a nitrogen atmosphere. The product was filtered, washed, and dried to obtain a carbon fiber / boron nitride composite.

3. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (1), the ratio of carbon fiber, acetone, and dopamine hydrochloride aqueous solution is 10 g: 200-300 mL: 400-600 mL; and the concentration of the dopamine hydrochloride aqueous solution is 1-3 mg / mL.

4. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (1), ultrasonic treatment is performed for 30 to 60 minutes; the pH is adjusted to 8.0 to 9.0 with Tris buffer; and the stirring reaction conditions are 20 to 35° C. and 12 to 24 hours.

5. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (2), the usage ratio of functionalized carbon fiber, monoepoxy POSS, and DMF is 10 g: 10-28 g: 250-400 mL.

6. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (2), ultrasonic treatment is performed for 30 to 60 minutes; and the stirring reaction conditions are 75 to 90° C. and 12 to 24 hours.

7. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (3), the ball milling conditions are ball milling at 300-500 r / min in a zirconia ball mill jar of a planetary ball mill for 12-36 hours; the ultrasonic treatment time is 60-120 minutes; the spray drying inlet temperature is 160-170°C, and the outlet temperature is 70-80°C.

8. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (3), the usage ratio of hydroxylated boron nitride and polyacrylic acid ethanol solution is 10 g: 250-400 mL; the concentration of polyacrylic acid ethanol solution is 0.25-1 wt %.

9. The high temperature resistant and environmentally friendly household ceramic according to claim 2, characterized in that: In step (4), the amount ratio of modified boron nitride, DMF, EDC, NHS, and modified carbon fiber is 10 g: 300-500 mL: 2-5 g: 1-3 g: 3-6 g; ultrasonic treatment is performed for 30-60 min; and the stirring reaction conditions are stirring reaction at 30-60 ° C for 8-14 h.

10. A method for preparing the high-temperature resistant and environmentally friendly household ceramic according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: dispersing the components in ethanol, ultrasonically treating the mixture for 30-60 minutes to uniformly mix the components, removing the ethanol, placing the mixture into a mold, pre-tightening the mixture at 7.8-8.2 MPa for 10-12 seconds, and then cold-pressing the mixture at 34-36 MPa for 7-9 minutes to obtain a ceramic green body; placing the ceramic green body in a sintering furnace, heating the temperature to 860-900° C. at a rate of 6-7° C. / min in a nitrogen atmosphere, keeping the temperature for 22-28 minutes, then heating the temperature to 1550-1600° C. at a rate of 1.5-2.5° C. / min, keeping the temperature for 2-3 hours, and naturally cooling the mixture to obtain the high-temperature resistant and environmentally friendly household ceramic.

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