An antibacterial material for cookware and its preparation method

Abstract

The present invention relates to the field of cookware materials, and provides a bacteriostatic material for cookware and a preparation method thereof. The material includes surface-modified boron nitride nanotube-coated silver filler, silica-supported doped titanium dioxide particles, polytetrafluoroethylene, silicone resin, heat stabilizer, polyethylene glycol 400, ethanol and curing agent. The preparation method is to mix the modified boron nitride nanotube-coated silver filler and silica-supported doped titanium dioxide particles with polyethylene glycol 400 and ethanol, add polytetrafluoroethylene, silicone resin and heat stabilizer after stirring to prepare a coating slurry, add a curing agent and stir evenly, coat it on the surface of the cookware substrate, and form a coating after high-temperature curing. The material adopts processes such as silver doping and silica loading, and exhibits excellent antibacterial properties, stability and wear resistance. The present invention solves the problem of insufficient antibacterial performance of the cookware coating and is applicable to the coating application of kitchen cookware.

Description

Technical Field

[0001] The present invention relates to the field of cookware materials, and particularly to an antibacterial material for cookware and a preparation method thereof. Background Art

[0002] With the continuous improvement of the quality of modern family life, the functionality and safety of kitchen cookware have become the focus of consumers' attention. As an important tool for food processing, cookware is prone to being invaded by microorganisms such as bacteria and molds during long-term use. Especially in complex use environments such as high humidity and high-temperature oil fumes, the growth of bacteria may lead to cross-contamination, threatening food safety and human health. Therefore, developing cookware materials with high antibacterial performance has become a key requirement in the cookware industry. At the same time, cookware also needs to withstand frequent friction, scratching, and high-temperature conditions during use, which puts higher requirements on the wear resistance of its surface coating. Cookware materials not only need to maintain long-term antibacterial performance in extreme environments but also need to have excellent wear resistance to ensure their service life and stability. Therefore, cookware coating materials that meet the dual requirements of antibacterial and wear resistance can not only significantly improve the hygienic safety of cookware but also extend its service life and reduce replacement costs, which is of great significance for enhancing the consumer experience and promoting the technological upgrading of the industry. The continuous optimization and breakthrough of material properties will provide higher-value-added products for the cookware industry and further broaden its application scenarios, thus promoting the widespread application of green, healthy, and high-performance cookware.

[0003] At present, certain achievements have been made in the research and development of cookware coating materials, but there are still many deficiencies. For example, the Chinese patent with the patent number CN107981702B discloses an antibacterial non-stick cookware and its manufacturing method, which achieves antibacterial effects by adding silver ions to the coating. However, due to the easy inactivation of silver ions in high-temperature environments, the long-term antibacterial performance is insufficient. At the same time, there are also obvious limitations in the wear resistance of existing coating materials. For example, the Chinese patent with the patent number CN107080468B introduces a high-hardness wear-resistant coating, but its wear resistance rapidly decreases in a strong friction environment and cannot meet the long-term use requirements of cookware. The main reasons for these deficiencies lie in the simplicity of the material system design and the limitations of its performance balance: on the one hand, traditional antibacterial materials usually rely on the physical or chemical effects of a single antibacterial agent and are difficult to maintain long-term antibacterial performance in complex environments; on the other hand, wear-resistant coatings usually aim at high hardness, but in actual use, they show low comprehensive performance due to the lack of flexibility and scratch resistance. Therefore, how to simultaneously achieve long-term antibacterial and high wear resistance in cookware materials has become a key problem in the current technical field and an important direction that the cookware industry urgently needs to break through. Summary of the Invention

[0004] (1) Technical Problems to be Solved

[0005] The object of the present invention is to provide an antibacterial material for cookware and its preparation method, so as to solve the problems of insufficient antibacterial and wear-resistant properties of current cookware materials.

[0006] (2) Technical solution

[0007] In order to achieve the above object, the present invention provides the following technical solution:

[0008] An antibacterial material for cookware, by weight, comprises the following components: 0.5 - 1.5 parts of surface-modified boron nitride nanotube-coated silver filler, 3 - 8 parts of silica-supported doped titanium dioxide particles, 25 - 35 parts of polytetrafluoroethylene, 10 - 15 parts of silicone resin, 1.0 - 3.0 parts of heat stabilizer, 0.5 - 1 part of polyethylene glycol 400, 45 - 55 parts of ethanol, and 1 - 3 parts of curing agent.

[0009] Furthermore, the preparation method of the surface-modified boron nitride nanotube-coated silver filler is as follows: By weight, add 10 - 18 parts of boron nitride nanotube-coated silver filler to 100 - 150 parts of absolute ethanol, stir at a stirring rate of 500 - 700 rpm for 30 - 40 min, and perform ultrasonic treatment after stirring to obtain a suspension. The parameters of the ultrasonic treatment are: acoustic power of 200 - 300 W, frequency of 40 - 50 kHz, and ultrasonic time of 20 - 30 min. Then continue to add 1.0 - 2.5 parts of KH-550, and then continue to stir at a stirring rate of 300 - 500 rpm at a temperature of 60 - 80 °C for 20 - 30 min. After stirring, separate the reaction solution by vacuum filtration, collect the filter residue, transfer the filter residue to a beaker, wash it 3 - 4 times with 100 - 150 mL of absolute ethanol, with each stirring time being 5 - 10 min, to remove unreacted KH-550 and impurities. After washing, filter to obtain the filter residue and place it in a vacuum drying oven, dry it at 60 - 70 °C for 10 - 12 h to obtain the surface-modified boron nitride nanotube-coated silver filler.

[0010] Further, the preparation method of the boron nitride tube coated with silver filler is as follows: By weight, 3.0 - 4.5 parts of boron nitride nanotubes are weighed and placed in a 250 mL beaker, and 100 - 150 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 500 - 700 rpm for 20 - 30 min. Subsequently, the beaker is placed in an ultrasonic cleaner and ultrasonically treated for 20 - 30 min under the conditions of an ultrasonic power of 200 - 300 W and a frequency of 40 - 50 kHz to form a boron nitride nanotube suspension. Additionally, 1.0 - 1.5 parts of silver nitrate are dissolved in 100 - 150 mL of deionized water to obtain a silver nitrate solution. The boron nitride nanotube suspension is added to the silver nitrate solution, placed on a magnetic stirrer, and stirred at a stirring rate of 500 - 700 rpm for 30 - 40 min. The mixed solution is transferred to a vacuum ultrasonic device and ultrasonically treated under a vacuum pressure condition of -0.08 to -0.1 MPa, with an ultrasonic power of 200 - 300 W, a frequency of 40 - 50 kHz, and a treatment time of 20 - 30 min. After the vacuum ultrasonic treatment, it is restored to normal pressure. The mixed solution is heated to 50 - 60 °C, and then a 0.1 mol / L glucose solution is slowly added dropwise at a dropping rate of 1 - 2 mL / min, with the total volume controlled at 20 - 30 mL. The constant temperature stirring is continued for 60 - 90 min until the color of the solution gradually changes from colorless to light gray. After the reaction solution is cooled, it is separated by vacuum filtration, the filter residue is collected, and washed 2 - 3 times with deionized water, with each amount being 100 - 150 mL. Subsequently, it is washed 1 - 2 times with absolute ethanol, with each amount being 50 - 100 mL. The washed filter residue is transferred to a vacuum drying oven and dried at 60 - 70 °C for 10 - 12 h to obtain the boron nitride tube coated with silver filler.

[0011] Further, the preparation method of the boron nitride nanotube is as follows: By weight, 5.0 - 8.0 parts of amorphous boron powder are weighed and placed in a graphite crucible of a high-temperature inert gas tubular furnace. The inside of the tubular furnace is evacuated to a vacuum, and the vacuum degree is controlled at -0.08 to -0.1 MPa. Then, argon is introduced for protection, and the flow rate is controlled at 200 - 300 mL / min. The furnace temperature is heated to 800 - 1100 °C at a heating rate of 5 - 10 °C / min and kept warm for 30 - 60 min to activate the boron powder. After the activation treatment is completed, the furnace temperature is continuously heated to 1200 - 1400 °C at a heating rate of 10 - 20 °C / min, and at the same time, 200 - 400 mL / min of ammonia gas is introduced for nitridation reaction. The holding time is 2 - 4 h. After the reaction is completed, the ammonia gas is stopped from being introduced, and 200 - 300 mL / min of argon gas is introduced for protection. The furnace temperature is cooled to room temperature at a cooling rate of 5 - 10 °C / min to obtain a preliminarily formed boron nitride product. After the preliminarily formed product is taken out and placed in a beaker, 100 - 150 mL of 0.1 - 0.5 mol / L dilute hydrochloric acid solution is added, and it is placed on a magnetic stirrer and stirred at a stirring rate of 300 - 500 rpm for 30 - 60 min for pickling treatment of the product. The pickled product is washed with deionized water 3 - 5 times, with each amount being 100 - 150 mL, until the pH of the washing liquid is close to neutral. Subsequently, it is washed with anhydrous ethanol 1 - 2 times, with each amount being 50 - 100 mL to complete further washing. The washed product is transferred to a vacuum drying oven and dried at 60 - 80 °C for 12 - 24 h to obtain dried boron nitride nanotubes.

[0012] Further, the average diameter of the surface-modified boron nitride nanotube coated with silver filler is 15 - 65 nm, and the average length is 550 - 1350 nm.

[0013] The design of the present invention using surface-modified boron nitride nanotubes coated with silver fillers is mainly used to enhance the long-term antibacterial performance and wear resistance of the cookware coating. Through the surface modification of boron nitride nanotubes and the coating design of silver ions during the preparation process, taking the high mechanical strength and excellent thermal stability of boron nitride nanotubes as the matrix, and combining with the broad-spectrum antibacterial characteristics of silver ions, the antibacterial ability of the coating material under high temperature and complex environments is effectively improved. In addition, by introducing KH-550 silane coupling agent during the coating process, the binding force between silver ions and boron nitride nanotubes is enhanced, not only improving the dispersibility of filler particles, but also enhancing the overall structural stability of the coating, thus providing excellent antibacterial persistence during long-term use. The preparation of boron nitride nanotubes adopts a high-temperature nitridation reaction process to ensure the integrity of its one-dimensional structure and size uniformity, while subsequent pickling and ultrasonic treatment further remove impurities, improving the purity and surface activity of the material, which lays a good foundation for the subsequent silver ion coating. During the silver ion coating process, through vacuum ultrasonic treatment and glucose reduction process, silver particles can be evenly distributed inside the boron nitride nanotubes to form highly efficient antibacterial active centers. In addition, the high strength of the modified boron nitride nanotubes and the uniform distribution of silver particles work together to improve the tolerance of the material to friction and scratching in the cookware coating, meeting the dual requirements of durability and hygiene in the high-frequency use scenarios of kitchen cookware. The synergy between the components fully reflects the design purpose, and the high performance of the cookware coating is achieved through the optimization of material properties.

[0014] Furthermore, the preparation method of the silica-loaded doped titanium dioxide particles is as follows: by weight, 5.0 - 7.0 parts of doped titanium dioxide particles are weighed and placed in a 250 mL beaker, 100 - 150 mL of absolute ethanol is added, the beaker is placed on a magnetic stirrer, and stirred at a stirring rate of 300 - 500 rpm for 30 - 40 min until a uniform dispersion is formed. Then, 3.0 - 5.0 parts of tetraethyl orthosilicate are weighed and slowly added to the above dispersion, and the dropping rate is controlled at 1.0 - 2.0 mL / min, while maintaining the stirring rate at 400 - 600 rpm, and stirring is continued for 30 - 60 min until the tetraethyl orthosilicate is completely mixed. Then, 0.1 mol / L hydrochloric acid solution is slowly added to the obtained mixed solution, the dropping rate is 0.5 - 1.0 mL / min, while maintaining the stirring rate at 300 - 500 rpm, the pH of the solution is adjusted to 2.0 - 4.0, and stirring is continued for 30 - 60 min to complete the hydrolysis process of tetraethyl orthosilicate. The obtained solution is transferred to a water bath at 80 - 90 °C, heated and kept stirring at a constant temperature for 60 - 90 min to promote the deposition of silica on the surface of the doped titanium dioxide particles. After the reaction is completed, the reaction solution is naturally cooled to room temperature, the obtained precipitate is separated by vacuum filtration, the filtrate is discarded, the precipitate is washed with deionized water 3 - 5 times, with 100 - 150 mL used each time, to remove unreacted impurities and by-products, and then washed with absolute ethanol 1 - 2 times, with 50 - 100 mL used each time. The washed precipitate is transferred to a vacuum drying oven and dried at 60 - 80 °C for 8 - 12 h to obtain dry silica-loaded doped titanium dioxide particles. The dried sample is placed in a tube furnace, heated to 400 - 500 °C at a heating rate of 3 - 5 °C / min, and kept in an air atmosphere for 2 - 4 hours. After the sintering treatment of the material, silica-loaded doped titanium dioxide particles are obtained.

[0015] Furthermore, the preparation method of the doped titanium dioxide particles is as follows: by weight, 10.0 - 15.0 parts of tetrabutyl titanate are weighed and placed in a 250 mL beaker, and 50 - 100 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 400 - 600 rpm for 30 - 40 min until a uniform tetrabutyl titanate solution is formed; 0.5 - 2.0 parts of silver nitrate are weighed and dissolved in 20 - 50 mL of deionized water to obtain a silver nitrate solution; the silver nitrate solution is slowly added dropwise to the tetrabutyl titanate solution, and the dropping rate is controlled at 1.0 - 2.0 mL / min, while maintaining the stirring rate at 500 - 700 rpm, and stirring is continued for 30 - 60 min to ensure that silver ions are uniformly dispersed in the tetrabutyl titanate solution. 0.1 mol / L hydrochloric acid solution is slowly added dropwise to the above mixture at a dropping rate of 1.0 - 2.0 mL / min, and the stirring rate is maintained at 400 - 600 rpm to adjust the pH of the solution to 1.0 - 3.0, promoting the hydrolysis reaction of tetrabutyl titanate. After the dropping is completed, the obtained solution is transferred to a reaction kettle and heated and kept warm at 80 - 100 °C for 6 - 12 h to complete the formation of titanate gel and the silver ion doping process. After the reaction is completed, the reaction kettle is naturally cooled to room temperature, and the obtained product is separated by vacuum filtration. The filtrate is discarded, and the filtered precipitate is washed with deionized water 3 - 5 times, with each amount being 100 - 150 mL, to remove residual impurities and unreacted silver ions. Subsequently, it is washed with absolute ethanol 1 - 2 times, with each amount being 50 - 100 mL, to facilitate drying. The washed precipitate is transferred to a vacuum drying oven and dried at 60 - 80 °C for 8 - 12 h to obtain dry silver-doped titanium dioxide precursor powder. The dried precursor powder is placed in a high-temperature tube furnace and heated to 450 - 550 °C at a heating rate of 3 - 5 °C / min and kept warm in an air atmosphere for 2 - 4 h. After sintering is completed, it is naturally cooled to room temperature, and after grinding and dispersion, doped titanium dioxide particles are obtained.

[0016] The design of the present invention using silica-loaded doped titanium dioxide particles is mainly used to enhance the antibacterial performance and stability of the cookware coating. By loading silica on the surface of the doped titanium dioxide particles, the synergistic optimization of material properties is achieved. During the preparation process, the doped titanium dioxide particles use tetrabutyl titanate as the precursor. Through silver ion doping and regulating the hydrolysis conditions, it is ensured that silver ions are evenly distributed in the titanium dioxide particle structure, thereby endowing the particles with excellent antibacterial performance and chemical stability. Subsequently, during the hydrolysis of tetraethyl orthosilicate, silica is gradually deposited on the surface of the doped titanium dioxide particles to form a uniformly covered loading layer. This design not only further improves the dispersibility and mechanical stability of the particles but also effectively enhances the durability and corrosion resistance of the coating in complex environments. By adjusting the pH value of the solution with hydrochloric acid and promoting the uniformity of the silica deposition process through water bath heating, the integrity of the material structure and the full play of its functionality are ensured. Finally, through the high-temperature sintering process, the crystal structure of the material is optimized and the surface activity of the particles is enhanced, thereby improving the antibacterial activity and environmental adaptability. The loading of silica not only provides a physical barrier to prevent the loss of silver ions but also improves the stability and service life of the overall material through the nano effect. The synergy between the components is fully reflected in this design. The doped titanium dioxide particles provide antibacterial active centers, and the silica loading layer enhances the mechanical properties and chemical stability of the material. These characteristics work together to significantly improve the comprehensive performance of the cookware coating and meet the dual requirements of antibacterial and stability in complex scenarios such as high-frequency use and high-temperature and humid environments.

[0017] Further, the average diameter of the silica-loaded doped titanium dioxide particles is 120 - 250 nm.

[0018] Further, the heat stabilizer is Irganox 1010 or benzotriazole.

[0019] Further, the curing agent is triethylenetetramine or di-tert-butyl peroxide.

[0020] The present invention also provides a preparation method for a cookware antibacterial material, comprising the following steps:

[0021] S1. Place the surface-modified boron nitride nanotube-coated silver filler, silica-loaded doped titanium dioxide particles, and polyethylene glycol in a 500 mL beaker, add half of the ethanol, place the beaker on a magnetic stirrer, and stir at a stirring rate of 500 - 700 rpm for 30 - 60 min until a uniform nano-material dispersion liquid is formed. Add polytetrafluoroethylene powder, silicone resin, and heat stabilizer to the above nano-material dispersion liquid, continue stirring at a rate of 400 - 600 rpm, gradually add the remaining half of the ethanol, and stir for 60 - 90 min to ensure that the polytetrafluoroethylene and silicone resin are fully mixed and uniformly dispersed, obtaining a uniformly mixed solution.

[0022] S2. Heat the uniformly mixed solution obtained in step S1 to 50 - 60 °C, raise the temperature at a rate of 2 - 5 °C / min, and maintain constant temperature stirring for 60 - 90 min to promote solvent volatilization and form a high-viscosity coating slurry. After the slurry is formed, slowly add a curing agent and continue stirring at a stirring rate of 400 - 600 rpm for 30 - 60 min to ensure that the curing agent and the slurry are fully and evenly mixed.

[0023] S3. Coat the obtained slurry on the surface of a clean and dry cookware substrate by spraying or scraping, control the coating thickness at 20 - 50 μm. After coating, place the cookware in an oven at 60 - 80 °C and keep it warm for 30 - 60 min to preliminarily dry the coating. Subsequently, transfer the cookware to a high-temperature oven, heat it to 250 - 300 °C at a heating rate of 5 - 10 °C / min, and keep it warm for 2 - 4 h to complete the curing and adhesion process of the coating. Let the cured cookware cool naturally to room temperature, and finally obtain a cookware antibacterial material.

[0024] (3) Beneficial technical effects

[0025] 1. Through the innovative design of surface-modified boron nitride nanotubes coated with silver fillers, the present invention is significantly superior to the prior art in enhancing the long-term antibacterial property and wear resistance of the cookware coating. The high strength and thermal stability of boron nitride nanotubes act synergistically with the antibacterial properties of silver ions, and combined with KH-550 silane coupling agent to enhance the binding force, achieving the persistence of antibacterial performance and the stability of the coating structure. The optimized preparation process ensures the purity and dispersibility of the material, enabling the silver particles to be evenly distributed to form efficient antibacterial active centers. The components act synergistically to improve the comprehensive performance of the coating in high-temperature and frequent friction environments, significantly extending the service life of the cookware, meeting the requirements of high-frequency use scenarios, and promoting the industry progress of antibacterial and wear-resistant coating technologies.

[0026] 2. Through the design of doped titanium dioxide particles loaded with silica, the present invention significantly improves the antibacterial performance and stability of the cookware coating, which is superior to the prior art. The doped titanium dioxide particles provide efficient antibacterial active centers, the uniform distribution of silver ions enhances the antibacterial effect, and the silica loading layer improves the mechanical properties and chemical stability through physical barriers and nano-effects. The components act synergistically to ensure the durability and safety of the coating in high-temperature and humid environments and frequent use scenarios, promoting the industry development of durable antibacterial coating technologies. Description of the drawings

[0027] Figure 1 It is a transmission electron microscope morphology diagram of surface-modified boron nitride nanotubes coated with silver fillers prepared in Example 1 of the present invention;

[0028] Figure 2SEM morphology diagram of the doped titanium dioxide particles prepared in Example 1 of the present invention;

[0029] Figure 3 SEM morphology diagram of the silica-loaded doped titanium dioxide particles prepared in Example 1 of the present invention. Detailed implementation manners

[0030] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] Example 1

[0032] A cookware antibacterial material and its preparation method, by weight, comprising the following components: 0.5 part of surface-modified boron nitride nanotube-coated silver filler, 3 parts of silica-loaded doped titanium dioxide particles, 25 parts of polytetrafluoroethylene, 10 parts of silicone resin, 1.0 part of heat stabilizer, 0.5 part of polyethylene glycol 400, 45 parts of ethanol, and 1 part of curing agent.

[0033] The preparation method of the surface-modified boron nitride nanotube-coated silver filler in this example is as follows: by weight, add 10 parts of boron nitride nanotube-coated silver filler to 100 parts of absolute ethanol, stir at a stirring rate of 500 rpm for 30 min, and perform ultrasonic treatment after stirring to obtain a suspension. The parameters of the ultrasonic treatment are: acoustic power is 200 W, frequency is 40 kHz, and ultrasonic time is 20 min. Then continue to add 1.0 part of KH-550, and then continue to stir at a stirring rate of 300 rpm at a temperature of 60°C for 20 min. After stirring, separate the reaction solution by vacuum filtration, collect the filter residue, transfer the filter residue to a beaker, wash it 3 times with 100 mL of absolute ethanol, with a stirring time of 5 min each time, to remove unreacted KH-550 and impurities. After washing, filter to obtain the filter residue and place it in a vacuum drying oven, dry it at 60°C for 10 h to obtain the surface-modified boron nitride nanotube-coated silver filler.

[0034] The preparation method of the silver filler-coated boron nitride tube in this embodiment is as follows: By weight, 3.0 parts of boron nitride nanotubes are weighed and placed in a 250 mL beaker, 100 mL of absolute ethanol is added, the beaker is placed on a magnetic stirrer, and stirred at a stirring rate of 500 rpm for 20 min. Subsequently, the beaker is placed in an ultrasonic cleaner and ultrasonically treated for 20 min under the conditions of an ultrasonic power of 200 W and a frequency of 40 kHz to form a boron nitride nanotube suspension. Additionally, 1.0 part of silver nitrate is dissolved in 100 mL of deionized water to obtain a silver nitrate solution. The boron nitride nanotube suspension is added to the silver nitrate solution, placed on a magnetic stirrer, and stirred at a stirring rate of 500 rpm for 30 min. The mixed solution is transferred to a vacuum ultrasonic device and ultrasonically treated under a vacuum pressure condition of -0.08 MPa, with an ultrasonic power of 200 W, a frequency of 40 kHz, and a treatment time of 20 min. After the vacuum ultrasonic treatment is completed, it is restored to normal pressure. The mixed solution is heated to 50 °C, and then a 0.1 mol / L glucose solution is slowly added dropwise at a dropping rate of 1 mL / min, with the total volume controlled at 20 mL. The constant temperature stirring is continued for 60 min until the color of the solution gradually changes from colorless to light gray. After the reaction solution is cooled, it is separated by vacuum filtration, the filter residue is collected, washed 2 times with deionized water, with each amount being 100 mL, and then washed 1 time with absolute ethanol, with each amount being 50 mL. The washed filter residue is transferred to a vacuum drying oven and dried at 60 °C for 10 h to obtain the silver filler-coated boron nitride tube.

[0035] The preparation method of the boron nitride tube in this embodiment is: By weight, 5.0 parts of amorphous boron powder are weighed and placed in a graphite crucible of a high-temperature inert gas tube furnace. The inside of the tube furnace is evacuated to a vacuum, and the vacuum degree is controlled at -0.08 MPa. Then, argon is introduced for protection, and the flow rate is controlled at 200 mL / min. The furnace temperature is heated to 800 °C at a heating rate of 5 °C / min and held for 30 min to activate the boron powder. After the activation treatment is completed, the furnace temperature is continued to be heated to 1200 °C at a heating rate of 10 °C / min, and at the same time, 200 mL / min of ammonia gas is introduced for nitridation reaction, and the holding time is 2 h. After the reaction is completed, the ammonia gas is stopped from being introduced, and 200 mL / min of argon gas is introduced for protection. The furnace temperature is cooled to room temperature at a cooling rate of 5 °C / min to obtain the preliminarily formed boron nitride product. After the preliminarily formed product is taken out and placed in a beaker, 100 mL of 0.1 mol / L dilute hydrochloric acid solution is added, placed on a magnetic stirrer, and stirred at a stirring rate of 300 rpm for 30 min for pickling treatment of the product. The pickled product is washed 3 times with deionized water, with each amount being 100 mL, until the pH of the washing solution is close to neutral, and then washed 1 time with absolute ethanol, with each amount being 50 mL to complete further washing. The washed product is transferred to a vacuum drying oven and dried at 60 °C for 12 h to obtain the dried boron nitride nanotubes.

[0036] The average diameter of the surface-modified boron nitride nanotubes coated with silver filler in this example is 15 nm, and the average length is 550 nm.

[0037] The preparation method of the doped titanium dioxide particles loaded with silica in this example is as follows: By weight, 5.0 parts of doped titanium dioxide particles are weighed and placed in a 250 mL beaker, and 100 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 300 rpm for 30 min until a uniform dispersion is formed. 3.0 parts of tetraethyl orthosilicate are weighed and slowly added to the above dispersion, and the dropping rate is controlled at 1.0 mL / min while maintaining the stirring rate at 400 rpm. Stir for another 30 min until the tetraethyl orthosilicate is completely mixed. 0.1 mol / L hydrochloric acid solution is slowly added to the obtained mixture at a dropping rate of 0.5 mL / min while maintaining the stirring rate at 300 rpm. Adjust the pH of the solution to 2.0 and continue stirring for 30 min to complete the hydrolysis process of tetraethyl orthosilicate. The obtained solution is transferred to a water bath at 80 °C, heated and kept under constant stirring for 60 min to promote the deposition of silica on the surface of the doped titanium dioxide particles. After the reaction is completed, the reaction solution is naturally cooled to room temperature. The obtained precipitate is separated by vacuum filtration, and the filtrate is discarded. The precipitate is washed 3 times with deionized water, 100 mL each time, to remove unreacted impurities and by-products, and then washed 1 time with absolute ethanol, 50 mL each time. The washed precipitate is transferred to a vacuum drying oven and dried at 60 °C for 8 h to obtain the dried doped titanium dioxide particles loaded with silica. The dried sample is placed in a tube furnace and heated to 400 °C at a heating rate of 3 °C / min and kept in an air atmosphere for 2 hours. After the sintering treatment of the material, the doped titanium dioxide particles loaded with silica are obtained.

[0038] The preparation method of the doped titanium dioxide particles in this embodiment is as follows: By weight, 10.0 parts of tetrabutyl titanate are weighed and placed in a 250 mL beaker, and 50 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 400 rpm for 30 min until a uniform tetrabutyl titanate solution is formed; 0.5 part of silver nitrate is weighed and dissolved in 20 mL of deionized water to obtain a silver nitrate solution; the silver nitrate solution is slowly added dropwise to the tetrabutyl titanate solution, and the dropping rate is controlled at 1.0 mL / min, while maintaining the stirring rate at 500 rpm, and stirring is continued for 30 min to ensure that silver ions are uniformly dispersed in the tetrabutyl titanate solution. 0.1 mol / L hydrochloric acid solution is slowly added dropwise to the above mixture at a dropping rate of 1.0 mL / min, and the stirring rate is maintained at 400 rpm to adjust the pH of the solution to 1.0 to promote the hydrolysis reaction of tetrabutyl titanate. After the dropping is completed, the obtained solution is transferred to a reaction kettle and heated and kept warm at 80 °C for 6 h to complete the formation of titanate gel and the silver ion doping process. After the reaction is completed, the reaction kettle is naturally cooled to room temperature, and the obtained product is separated by vacuum filtration. The filtrate is discarded, and the filtered precipitate is washed 3 times with deionized water, with each amount being 100 mL, to remove residual impurities and unreacted silver ions. Subsequently, it is washed 1 time with absolute ethanol, with each amount being 50 mL, to promote drying. The washed precipitate is transferred to a vacuum drying oven and dried at 60 °C for 8 h to obtain a dried silver-doped titanium dioxide precursor powder. The dried precursor powder is placed in a high-temperature tube furnace and heated to 450 °C at a heating rate of 3 °C / min and kept warm in an air atmosphere for 2 h. After sintering is completed, it is naturally cooled to room temperature, and after grinding and dispersion, doped titanium dioxide particles are obtained.

[0039] The average diameter of the doped titanium dioxide particles loaded with silica in this embodiment is 120 nm.

[0040] The heat stabilizer in this embodiment is Irganox 1010.

[0041] The curing agent in this embodiment is di-tert-butyl peroxide.

[0042] A preparation method of a pan antibacterial material in this embodiment includes the following steps:

[0043] S1. Place the surface-modified boron nitride nanotubes coated with silver fillers, doped titanium dioxide particles loaded with silica, and polyethylene glycol in a 500 mL beaker. Add half of the ethanol, place the beaker on a magnetic stirrer, and stir at a stirring rate of 500 rpm for 30 min until a uniform dispersion of nanomaterials is formed. Add polytetrafluoroethylene powder, silicone resin, and heat stabilizer to the above nanomaterial dispersion, continue stirring at a rate of 400 rpm, gradually add the remaining half of the ethanol, and stir for 60 min to ensure that the polytetrafluoroethylene and silicone resin are fully mixed and uniformly dispersed, obtaining a uniformly mixed solution.

[0044] S2. Heat the uniformly mixed solution obtained in step S1 to 50 °C, heat it at a heating rate of 2 °C / min, and maintain constant stirring for 60 min to promote solvent evaporation and form a high-viscosity coating slurry. After the slurry is formed, slowly add the curing agent and continue stirring at a rate of 400 rpm for 30 min to ensure that the curing agent is fully mixed and uniform with the slurry.

[0045] S3. Coat the obtained slurry on the surface of a clean and dry cookware substrate by means of scraping, control the coating thickness at 20 μm. After coating, place the cookware in an oven at 60 °C and keep it warm for 30 min to preliminarily dry the coating. Then transfer the cookware to a high-temperature oven, heat it to 250 °C at a heating rate of 5 °C / min, and keep it warm for 2 h to complete the curing and adhesion process of the coating. Let the cookware after curing cool naturally to room temperature, and finally obtain a cookware antibacterial material.

[0046] This study verified the structure and properties of the prepared materials in Example 1 of the present invention through microscopic analysis. Figure 1 It is a transmission electron microscope morphology diagram of surface-modified boron nitride nanotubes coated with silver fillers. It can be clearly observed that silver is uniformly coated inside the boron nitride nanotubes, proving the effectiveness of material preparation. Figure 2 It is a scanning electron microscope morphology diagram of doped titanium dioxide particles, showing that the particle surface is smooth, further corroborating the morphological characteristics of the prepared particles. Figure 3 It is a scanning electron microscope morphology diagram of doped titanium dioxide particles loaded with silica. It can be clearly seen that the surface morphology of the particles is rough, indicating the successful loading of silica and the significant change in the material structure. The above results fully prove the effectiveness of the preparation method of the present invention and the expected construction of the material structure.

[0047] Example 2

[0048] An antibacterial material for cookware and its preparation method. In terms of parts by weight, it includes the following components: 0.8 part of silver-coated surface-modified boron nitride nanotubes, 4.5 parts of doped titanium dioxide particles loaded with silica, 28 parts of polytetrafluoroethylene, 11.5 parts of silicone resin, 1.6 parts of heat stabilizer, 0.6 part of polyethylene glycol 400, 48 parts of ethanol, and 1.6 parts of curing agent.

[0049] The preparation method of the silver-coated surface-modified boron nitride nanotubes in this example is as follows: In terms of parts by weight, add 12.4 parts of silver-coated boron nitride nanotubes to 115 parts of absolute ethanol, stir at a stirring rate of 560 rpm for 33 minutes. After stirring, perform ultrasonic treatment to obtain a suspension. The parameters of the ultrasonic treatment are: acoustic power is 230 W, frequency is 43 kHz, and ultrasonic time is 23 minutes. Then continue to add 1.5 parts of KH-550. Then, at a temperature of 66 °C, continue to stir at a stirring rate of 360 rpm for 23 minutes. After stirring, separate the reaction solution by vacuum filtration, collect the filter residue, transfer the filter residue to a beaker, wash it 3 times with 115 mL of absolute ethanol, with each stirring time being 6.5 minutes to remove unreacted KH-550 and impurities. After washing, filter to obtain the filter residue and place it in a vacuum drying oven, dry it at 63 °C for 10.6 hours to obtain the silver-coated surface-modified boron nitride nanotubes.

[0050] The preparation method of the boron nitride tube coated with silver filler in this embodiment is as follows: By weight, 3.5 parts of boron nitride nanotubes are weighed and placed in a 250 mL beaker, and 115 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 560 rpm for 23 min. Subsequently, the beaker is placed in an ultrasonic cleaner and ultrasonically treated for 23 min under the conditions of an ultrasonic power of 230 W and a frequency of 43 kHz to form a boron nitride nanotube suspension. Additionally, 1.2 parts of silver nitrate are weighed and dissolved in 115 mL of deionized water to obtain a silver nitrate solution. The boron nitride nanotube suspension is added to the silver nitrate solution, placed on a magnetic stirrer, and stirred at a stirring rate of 560 rpm for 33 min. The mixed solution is transferred to a vacuum ultrasonic device and ultrasonically treated under a vacuum pressure condition of -0.086 MPa, with an ultrasonic power of 230 W, a frequency of 43 kHz, and a treatment time of 23 min. After the vacuum ultrasonic treatment is completed, it is restored to normal pressure. The mixed solution is heated to 53 °C, and then a 0.1 mol / L glucose solution is slowly added dropwise at a dropping rate of 1.3 mL / min, with the total volume controlled at 23 mL. The constant temperature stirring is continued for 69 min until the color of the solution gradually changes from colorless to light gray. After the reaction solution is cooled, it is separated by vacuum filtration, and the filter residue is collected and washed 2 times with deionized water, with each usage amount being 115 mL. Subsequently, it is washed 1 time with absolute ethanol, with each usage amount being 65 mL. The washed filter residue is transferred to a vacuum drying oven and dried at 63 °C for 10.6 h to obtain the boron nitride tube coated with silver filler.

[0051] The preparation method of the boron nitride tube in this embodiment is as follows: By weight, 5.9 parts of amorphous boron powder are weighed and placed in a graphite crucible of a high-temperature inert atmosphere tube furnace. The inside of the tube furnace is evacuated to a vacuum, and the vacuum degree is controlled at -0.086 MPa. Then, argon is introduced for protection, and the flow rate is controlled at 230 mL / min. The furnace temperature is heated to 890 °C at a heating rate of 6.5 °C / min and held for 39 min to activate the boron powder. After the activation treatment is completed, the furnace temperature is continued to be heated to 1260 °C at a heating rate of 13 °C / min, and at the same time, 260 mL / min of ammonia is introduced for nitridation reaction. The holding time is 2.6 h. After the reaction is completed, the ammonia introduction is stopped, and 230 mL / min of argon is introduced for protection. The furnace temperature is cooled to room temperature at a cooling rate of 6.5 °C / min to obtain the preliminarily formed boron nitride product. After the preliminarily formed product is taken out and placed in a beaker, 115 mL of 0.22 mol / L dilute hydrochloric acid solution is added, and it is placed on a magnetic stirrer and stirred at a stirring rate of 360 rpm for 39 min for pickling treatment of the product. The pickled product is washed 3 times with deionized water, with a dosage of 115 mL each time, until the pH of the washing solution is close to neutral. Subsequently, it is washed once with anhydrous ethanol, with a dosage of 65 mL each time, to complete further cleaning. The washed product is transferred to a vacuum drying oven and dried at 66 °C for 15.6 h to obtain the dried boron nitride nanotubes.

[0052] The average diameter of the surface-modified boron nitride tube coated with silver filler in this embodiment is 37 nm, and the average length is 790 nm.

[0053] The preparation method of the silica-loaded doped titanium dioxide particles in this embodiment is as follows: By weight, 5.6 parts of doped titanium dioxide particles are weighed and placed in a 250 mL beaker. 115 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 360 rpm for 33 min until a uniform dispersion is formed. 3.6 parts of tetraethyl orthosilicate are weighed and slowly added to the above dispersion. The dropping rate is controlled at 1.3 mL / min, and at the same time, the stirring rate is maintained at 460 rpm. Stirring is continued for 39 min until the tetraethyl orthosilicate is completely mixed. 0.1 mol / L hydrochloric acid solution is slowly added to the obtained mixture. The dropping rate is 0.65 mL / min, and at the same time, the stirring rate is maintained at 360 rpm. The pH of the solution is adjusted to 2.6, and stirring is continued for 39 min to complete the hydrolysis process of tetraethyl orthosilicate. The obtained solution is transferred to a water bath at 83 °C, heated and kept stirring at a constant temperature for 69 min to promote the deposition of silica on the surface of the doped titanium dioxide particles. After the reaction is completed, the reaction solution is naturally cooled to room temperature. The obtained precipitate is separated by vacuum filtration, and the filtrate is discarded. The precipitate is washed 3 times with deionized water, with a dosage of 115 mL each time, to remove unreacted impurities and by-products. Subsequently, it is washed 1 time with absolute ethanol, with a dosage of 65 mL each time. The washed precipitate is transferred to a vacuum drying oven and dried at 66 °C for 9.2 h to obtain the dried silica-loaded doped titanium dioxide particles. The dried sample is placed in a tube furnace and heated to 430 °C at a heating rate of 3.6 °C / min, and kept warm in an air atmosphere for 2.6 hours. After the sintering treatment of the material, silica-loaded doped titanium dioxide particles are obtained.

[0054] The preparation method of the doped titanium dioxide particles in this embodiment is as follows: By weight, 11.5 parts of tetrabutyl titanate are weighed and placed in a 250 mL beaker, and 65 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 460 rpm for 33 min until a uniform tetrabutyl titanate solution is formed; 0.95 part of silver nitrate is weighed and dissolved in 29 mL of deionized water to obtain a silver nitrate solution; the silver nitrate solution is slowly added dropwise to the tetrabutyl titanate solution, and the dropping rate is controlled at 1.3 mL / min, while maintaining the stirring rate at 560 rpm, and stirring is continued for 39 min to ensure that silver ions are uniformly dispersed in the tetrabutyl titanate solution. 0.1 mol / L hydrochloric acid solution is slowly added dropwise to the above mixture at a dropping rate of 1.3 mL / min, and the stirring rate is maintained at 460 rpm to adjust the pH of the solution to 1.6 to promote the hydrolysis reaction of tetrabutyl titanate. After the dropping is completed, the obtained solution is transferred to a reaction kettle and heated and kept warm at 86 °C for 7.8 h to complete the formation of titanate gel and the silver ion doping process. After the reaction is completed, the reaction kettle is naturally cooled to room temperature, and the obtained product is separated by vacuum filtration. The filtrate is discarded, and the filtered precipitate is washed 3 times with deionized water, with a dosage of 115 mL each time, to remove residual impurities and unreacted silver ions. Subsequently, it is washed 1 time with absolute ethanol, with a dosage of 65 mL each time, to promote drying. The washed precipitate is transferred to a vacuum drying oven and dried at 66 °C for 9.2 h to obtain dry silver-doped titanium dioxide precursor powder. The dried precursor powder is placed in a high-temperature tube furnace and heated to 480 °C at a heating rate of 3.6 °C / min and kept warm in an air atmosphere for 2.6 h. After sintering is completed, it is naturally cooled to room temperature, and after grinding and dispersion, doped titanium dioxide particles are obtained.

[0055] The average diameter of the silica-supported doped titanium dioxide particles in this embodiment is 159 nm.

[0056] The heat stabilizer in this embodiment is benzotriazole.

[0057] The curing agent in this embodiment is di-tert-butyl peroxide.

[0058] A preparation method of a pan antibacterial material in this embodiment includes the following steps:

[0059] S1. Place the surface-modified boron nitride nanotube-coated silver filler, silica-loaded doped titanium dioxide particles, and polyethylene glycol in a 500 mL beaker, add half of the ethanol, place the beaker on a magnetic stirrer, and stir at a stirring rate of 560 rpm for 39 min until a uniform nanomaterial dispersion is formed. Then add polytetrafluoroethylene powder, silicone resin, and heat stabilizer to the above nanomaterial dispersion, continue stirring at a rate of 460 rpm, gradually add the remaining half of the ethanol, and stir for 69 min to ensure that the polytetrafluoroethylene and silicone resin are fully mixed and uniformly dispersed, obtaining a uniformly mixed solution.

[0060] S2. Heat the uniformly mixed solution obtained in step S1 to 53 °C, heat it at a heating rate of 2.9 °C / min, and maintain constant-temperature stirring for 69 min to promote solvent evaporation and form a high-viscosity coating slurry. After the slurry is formed, slowly add the curing agent and continue stirring at a stirring rate of 460 rpm for 39 min to ensure that the curing agent is fully mixed and uniform with the slurry.

[0061] S3. Coat the obtained slurry on the surface of a clean and dry cookware substrate by spraying, control the coating thickness at 29 μm. After coating, place the cookware in an oven at 66 °C and keep it warm for 39 min to preliminarily dry the coating. Then transfer the cookware to a high-temperature oven, heat it to 265 °C at a heating rate of 6.5 °C / min, and keep it warm for 2.6 h to complete the curing and adhesion process of the coating. Let the cured cookware cool naturally to room temperature, and finally obtain a cookware antibacterial material.

[0062] Example 3

[0063] A cookware antibacterial material and its preparation method, in parts by weight, comprising the following components: 1.1 parts of surface-modified boron nitride nanotube-coated silver filler, 6 parts of silica-loaded doped titanium dioxide particles, 31 parts of polytetrafluoroethylene, 13 parts of silicone resin, 2.2 parts of heat stabilizer, 0.8 part of polyethylene glycol 400, 51 parts of ethanol, and 2.2 parts of curing agent.

[0064] The preparation method of the surface-modified boron nitride tube coated with silver filler in this embodiment is as follows: By weight, 15 parts of the boron nitride tube coated with silver filler are added to 130 parts of absolute ethanol, and stirred at a stirring rate of 620 rpm for 36 min. After stirring, ultrasonic treatment is carried out to obtain a suspension. The parameters of the ultrasonic treatment are: the acoustic power is 260 W, the frequency is 46 kHz, and the ultrasonic time is 26 min. Then, 1.9 parts of KH-550 are added continuously. Then, at a temperature of 72 °C, stirring is continued at a stirring rate of 420 rpm for 26 min. After stirring, the reaction solution is separated by vacuum filtration, and the filter residue is collected. The filter residue is transferred to a beaker and washed 3 times with 130 mL of absolute ethanol, with each stirring time being 8 min, to remove unreacted KH-550 and impurities. After washing, the filter residue obtained by filtration is placed in a vacuum drying oven and dried at 66 °C for 11 h to obtain the surface-modified boron nitride tube coated with silver filler.

[0065] The preparation method of the boron nitride tube coated with silver filler in this embodiment is as follows: By weight, 3.9 parts of boron nitride nanotubes are weighed and placed in a 250 mL beaker, and 130 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 620 rpm for 26 min. Subsequently, the beaker is placed in an ultrasonic cleaner and ultrasonically treated for 26 min under the conditions of an ultrasonic power of 260 W and a frequency of 46 kHz to form a boron nitride nanotube suspension. Additionally, 1.3 parts of silver nitrate are weighed and dissolved in 130 mL of deionized water to obtain a silver nitrate solution. The boron nitride nanotube suspension is added to the silver nitrate solution, placed on a magnetic stirrer, and stirred at a stirring rate of 620 rpm for 36 min. The mixed solution is transferred to a vacuum ultrasonic device and ultrasonically treated under a vacuum pressure condition of -0.092 MPa, with an ultrasonic power of 260 W, a frequency of 46 kHz, and a treatment time of 26 min. After the vacuum ultrasonic treatment is completed, the pressure is restored to normal pressure, and the mixed solution is heated to 56 °C. Subsequently, a 0.1 mol / L glucose solution is slowly added dropwise at a dropping rate of 1.6 mL / min, and the total volume is controlled at 26 mL. Stirring is continued at a constant temperature for 78 min until the color of the solution gradually changes from colorless to light gray. After the reaction solution is cooled, it is separated by vacuum filtration, and the filter residue is collected and washed 2 times with deionized water, with each amount being 130 mL. Subsequently, it is washed 1 time with absolute ethanol, with each amount being 80 mL. The washed filter residue is transferred to a vacuum drying oven and dried at 66 °C for 11 h to obtain the boron nitride tube coated with silver filler.

[0066] The preparation method of the boron nitride tube in this embodiment is as follows: Weigh 6.8 parts of amorphous boron powder by weight and place it in a graphite crucible of a high-temperature inert gas tube furnace. Pump the inside of the tube furnace to vacuum, control the vacuum degree at -0.092 MPa, then introduce argon for protection, control the flow rate at 260 mL / min, heat the furnace temperature to 980 °C at a heating rate of 8 °C / min, and keep it warm for 48 min to activate the boron powder. After the activation treatment is completed, continue to heat the furnace temperature to 1320 °C at a heating rate of 16 °C / min, and at the same time introduce 320 mL / min of ammonia for nitridation reaction. The holding time is 3.2 h. After the reaction is completed, stop the introduction of ammonia, introduce 260 mL / min of argon for protection, and cool the furnace temperature to room temperature at a cooling rate of 8 °C / min to obtain the preliminarily formed boron nitride product. Take out the preliminarily formed product and place it in a beaker, add 130 mL of 0.34 mol / L dilute hydrochloric acid solution, place it on a magnetic stirrer, stir at a stirring rate of 420 rpm for 48 min to perform pickling treatment on the product. Wash the pickled product 4 times with deionized water, with a dosage of 130 mL each time, until the pH of the washing liquid is close to neutral. Then wash it once with anhydrous ethanol, with a dosage of 80 mL each time to complete further cleaning. Transfer the washed product to a vacuum drying oven and dry it at 72 °C for 19.2 h to obtain the dried boron nitride nanotubes.

[0067] The average diameter of the surface-modified boron nitride tube coated with silver filler in this embodiment is 49 nm, and the average length is 1030 nm.

[0068] The preparation method of the silica-loaded doped titanium dioxide particles in this embodiment is as follows: By weight, 6.2 parts of doped titanium dioxide particles are weighed and placed in a 250 mL beaker. 130 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 420 rpm for 36 min until a uniform dispersion is formed. 4.2 parts of tetraethyl orthosilicate are weighed and slowly added to the above dispersion. The dropping rate is controlled at 1.6 mL / min, and at the same time, the stirring rate is maintained at 520 rpm. Stirring is continued for 48 min until the tetraethyl orthosilicate is completely mixed. 0.1 mol / L hydrochloric acid solution is slowly added to the obtained mixed solution at a dropping rate of 0.8 mL / min, and at the same time, the stirring rate is maintained at 420 rpm. The pH of the solution is adjusted to 3.2, and stirring is continued for 48 min to complete the hydrolysis process of tetraethyl orthosilicate. The obtained solution is transferred to a water bath at 86 °C, heated and kept under constant stirring for 78 min to promote the deposition of silica on the surface of the doped titanium dioxide particles. After the reaction is completed, the reaction solution is naturally cooled to room temperature. The obtained precipitate is separated by vacuum filtration, and the filtrate is discarded. The precipitate is washed 4 times with deionized water, with a dosage of 130 mL each time, to remove unreacted impurities and by-products. Subsequently, it is washed 1 time with absolute ethanol, with a dosage of 80 mL each time. The washed precipitate is transferred to a vacuum drying oven and dried at 72 °C for 10.4 h to obtain the dried silica-loaded doped titanium dioxide particles. The dried sample is placed in a tube furnace and heated to 460 °C at a heating rate of 4.2 °C / min and kept in an air atmosphere for 3.2 hours. After the sintering treatment of the material, the silica-loaded doped titanium dioxide particles are obtained.

[0069] The preparation method of the doped titanium dioxide particles in this embodiment is as follows: by weight, 13 parts of tetrabutyl titanate are weighed and placed in a 250 mL beaker, 80 mL of absolute ethanol is added, and the beaker is placed on a magnetic stirrer and stirred at a stirring rate of 520 rpm for 36 min until a uniform tetrabutyl titanate solution is formed; 1.4 parts of silver nitrate are weighed and dissolved in 38 mL of deionized water to obtain a silver nitrate solution; the silver nitrate solution is slowly added dropwise to the tetrabutyl titanate solution, and the dropping rate is controlled at 1.6 mL / min, while maintaining the stirring rate at 620 rpm, and stirring is continued for 48 min to ensure that silver ions are uniformly dispersed in the tetrabutyl titanate solution. Then, a 0.1 mol / L hydrochloric acid solution is slowly added dropwise to the above mixture at a dropping rate of 1.6 mL / min, and the stirring rate is maintained at 520 rpm to adjust the pH of the solution to 2.2 to promote the hydrolysis reaction of tetrabutyl titanate. After the dropping is completed, the obtained solution is transferred to a reaction kettle and heated and kept warm at 92 °C for 9.6 h to complete the formation of titanate gel and the silver ion doping process. After the reaction is completed, the reaction kettle is naturally cooled to room temperature, and the obtained product is separated by vacuum filtration. The filtrate is discarded, and the filtered precipitate is washed 4 times with deionized water, 130 mL each time, to remove residual impurities and unreacted silver ions. Then, it is washed 1 time with absolute ethanol, 80 mL each time, to promote drying. The washed precipitate is transferred to a vacuum drying oven and dried at 72 °C for 10.4 h to obtain dry silver-doped titanium dioxide precursor powder. The dried precursor powder is placed in a high-temperature tube furnace and heated to 510 °C at a heating rate of 4.2 °C / min and kept warm in an air atmosphere for 3.2 h. After sintering is completed, it is naturally cooled to room temperature, and after grinding and dispersion, doped titanium dioxide particles are obtained.

[0070] The average diameter of the silica-supported doped titanium dioxide particles in this embodiment is 198 nm.

[0071] The heat stabilizer in this embodiment is Irganox 1010.

[0072] The curing agent in this embodiment is triethylenetetramine.

[0073] A preparation method of a pan antibacterial material in this embodiment includes the following steps:

[0074] S1. Place the surface-modified boron nitride nanotube-coated silver filler, silica-loaded doped titanium dioxide particles, and polyethylene glycol in a 500 mL beaker. Add half of the ethanol, place the beaker on a magnetic stirrer, and stir at a stirring rate of 620 rpm for 48 min until a uniform nanomaterial dispersion is formed. Add polytetrafluoroethylene powder, silicone resin, and heat stabilizer to the above nanomaterial dispersion, continue stirring at a rate of 520 rpm, gradually add the remaining half of the ethanol, and stir for 78 min to ensure that the polytetrafluoroethylene and silicone resin are fully mixed and uniformly dispersed, obtaining a uniformly mixed solution.

[0075] S2. Heat the uniformly mixed solution obtained in step S1 to 56 °C, heat it at a heating rate of 3.8 °C / min, and maintain constant-temperature stirring for 78 min to promote solvent evaporation and form a high-viscosity coating slurry. After the slurry is formed, slowly add the curing agent and continue stirring at a stirring rate of 520 rpm for 48 min to ensure that the curing agent is fully mixed and uniform with the slurry.

[0076] S3. Coat the obtained slurry on the surface of a clean and dry cookware substrate by means of scraping, control the coating thickness at 38 μm. After coating, place the cookware in an oven at 72 °C and keep it warm for 48 min to preliminarily dry the coating. Subsequently, transfer the cookware to a high-temperature oven, heat it to 280 °C at a heating rate of 8 °C / min, and keep it warm for 3.2 h to complete the curing and adhesion process of the coating. Naturally cool the cured cookware to room temperature to finally obtain a cookware antibacterial material.

[0077] Example 4

[0078] An antibacterial material for cookware and its preparation method, by weight, includes the following components: 1.5 parts of surface-modified boron nitride nanotube-coated silver filler, 8 parts of silica-loaded doped titanium dioxide particles, 35 parts of polytetrafluoroethylene, 15 parts of silicone resin, 3.0 parts of heat stabilizer, 1 part of polyethylene glycol 400, 55 parts of ethanol, and 3 parts of curing agent.

[0079] The preparation method of the surface-modified boron nitride tube coated with silver filler in this embodiment is as follows: By weight, 18 parts of the boron nitride tube coated with silver filler are added to 150 parts of absolute ethanol, and stirred at a stirring rate of 700 rpm for 40 min. After stirring, ultrasonic treatment is carried out to obtain a suspension. The parameters of the ultrasonic treatment are: the acoustic power is 300 W, the frequency is 50 kHz, and the ultrasonic time is 30 min. Then, 2.5 parts of KH-550 are added continuously. Then, at a temperature of 80 °C, stirring is continued at a stirring rate of 500 rpm for 30 min. After stirring, the reaction solution is separated by vacuum filtration, and the filter residue is collected. The filter residue is transferred to a beaker and washed 4 times with 150 mL of absolute ethanol, and the stirring time for each time is 10 min to remove unreacted KH-550 and impurities. After washing, the filter residue obtained by filtration is placed in a vacuum drying oven and dried at 70 °C for 12 h to obtain the surface-modified boron nitride tube coated with silver filler.

[0080] The preparation method of the boron nitride tube coated with silver filler in this embodiment is as follows: By weight, 4.5 parts of boron nitride nanotubes are weighed and placed in a 250 mL beaker, and 150 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 700 rpm for 30 min. Subsequently, the beaker is placed in an ultrasonic cleaner and ultrasonically treated for 30 min under the conditions of an ultrasonic power of 300 W and a frequency of 50 kHz to form a boron nitride nanotube suspension. Additionally, 1.5 parts of silver nitrate are weighed and dissolved in 150 mL of deionized water to obtain a silver nitrate solution. The boron nitride nanotube suspension is added to the silver nitrate solution, placed on a magnetic stirrer, and stirred at a stirring rate of 700 rpm for 40 min. The mixed solution is transferred to a vacuum ultrasonic device and ultrasonically treated under a vacuum pressure condition of -0.1 MPa. The ultrasonic power is 300 W, the frequency is 50 kHz, and the treatment time is 30 min. After the vacuum ultrasonic treatment ends, it is restored to normal pressure, and the mixed solution is heated to 60 °C. Subsequently, a 0.1 mol / L glucose solution is slowly added dropwise at a dropping rate of 2 mL / min, and the total volume is controlled at 30 mL. Stirring is continued at a constant temperature for 90 min until the color of the solution gradually changes from colorless to light gray. After the reaction solution is cooled, it is separated by vacuum filtration, and the filter residue is collected and washed 3 times with deionized water, with each amount being 150 mL. Subsequently, it is washed 2 times with absolute ethanol, with each amount being 100 mL. The washed filter residue is transferred to a vacuum drying oven and dried at 70 °C for 12 h to obtain the boron nitride tube coated with silver filler.

[0081] The preparation method of the boron nitride tube in this embodiment is as follows: By weight, 8.0 parts of amorphous boron powder are weighed and placed in a graphite crucible of a high-temperature inert gas tube furnace. The inside of the tube furnace is evacuated to a vacuum, and the vacuum degree is controlled at -0.1 MPa. Then, argon is introduced for protection, and the flow rate is controlled at 300 mL / min. The furnace temperature is heated to 1100 °C at a heating rate of 10 °C / min and held for 60 min to activate the boron powder. After the activation treatment is completed, the furnace temperature is continued to be heated to 1400 °C at a heating rate of 20 °C / min, and at the same time, 400 mL / min of ammonia gas is introduced for nitridation reaction. The holding time is 4 h. After the reaction is completed, the ammonia gas introduction is stopped, and 300 mL / min of argon gas is introduced for protection. The furnace temperature is cooled to room temperature at a cooling rate of 10 °C / min to obtain the preliminarily formed boron nitride product. After taking out the preliminarily formed product, it is placed in a beaker, 150 mL of 0.5 mol / L dilute hydrochloric acid solution is added, and it is placed on a magnetic stirrer and stirred at a stirring rate of 500 rpm for 60 min for pickling treatment of the product. The pickled product is washed 5 times with deionized water, with each amount being 150 mL, until the pH of the washing liquid is close to neutral. Subsequently, it is washed 2 times with absolute ethanol, with each amount being 100 mL to complete further cleaning. The cleaned product is transferred to a vacuum drying oven and dried at 80 °C for 24 h to obtain the dried boron nitride nanotubes.

[0082] The average diameter of the surface-modified boron nitride tube coated with silver filler in this embodiment is 65 nm, and the average length is 1350 nm.

[0083] The preparation method of the silica-loaded doped titanium dioxide particles in this embodiment is as follows: by weight, 7.0 parts of doped titanium dioxide particles are weighed and placed in a 250 mL beaker, 150 mL of absolute ethanol is added, and the beaker is placed on a magnetic stirrer and stirred at a stirring rate of 500 rpm for 40 min until a uniform dispersion is formed. 5.0 parts of tetraethyl orthosilicate are weighed and slowly added to the above dispersion, and the dropping rate is controlled at 2.0 mL / min, while maintaining the stirring rate at 600 rpm, and stirring is continued for 60 min until the tetraethyl orthosilicate is completely mixed. 0.1 mol / L hydrochloric acid solution is slowly added to the obtained mixed solution at a dropping rate of 1.0 mL / min, while maintaining the stirring rate at 500 rpm, the pH of the solution is adjusted to 4.0, and stirring is continued for 60 min to complete the hydrolysis process of tetraethyl orthosilicate. The obtained solution is transferred to a water bath at 90 °C, heated and kept stirring at a constant temperature for 90 min to promote the deposition of silica on the surface of the doped titanium dioxide particles. After the reaction is completed, the reaction solution is naturally cooled to room temperature, and the obtained precipitate is separated by vacuum filtration, and the filtrate is discarded. The precipitate is washed 5 times with deionized water, 150 mL each time, to remove unreacted impurities and by-products, and then washed 2 times with absolute ethanol, 100 mL each time. The washed precipitate is transferred to a vacuum drying oven and dried at 80 °C for 12 h to obtain dry silica-loaded doped titanium dioxide particles. The dried sample is placed in a tubular furnace and heated to 500 °C at a heating rate of 5 °C / min and kept in an air atmosphere for 4 hours. After the sintering treatment of the material, silica-loaded doped titanium dioxide particles are obtained.

[0084] The preparation method of the doped titanium dioxide particles in this embodiment is as follows: By weight, 15 parts of tetrabutyl titanate are weighed and placed in a 250 mL beaker, and 100 mL of absolute ethanol is added. The beaker is placed on a magnetic stirrer and stirred at a stirring rate of 600 rpm for 40 min until a uniform tetrabutyl titanate solution is formed; 1.8 parts of silver nitrate are weighed and dissolved in 45 mL of deionized water to obtain a silver nitrate solution; the silver nitrate solution is slowly added dropwise to the tetrabutyl titanate solution, and the dropping rate is controlled at 2.0 mL / min, while maintaining the stirring rate at 700 rpm, and stirring is continued for 60 min to ensure that silver ions are uniformly dispersed in the tetrabutyl titanate solution. 0.1 mol / L hydrochloric acid solution is slowly added dropwise to the above mixture at a dropping rate of 2.0 mL / min, and the stirring rate is maintained at 600 rpm to adjust the pH of the solution to 3.0 to promote the hydrolysis reaction of tetrabutyl titanate. After the dropping is completed, the obtained solution is transferred to a reaction kettle and heated and kept warm at 95 °C for 12 h to complete the formation of titanate gel and the silver ion doping process. After the reaction is completed, the reaction kettle is naturally cooled to room temperature. The obtained product is separated by vacuum filtration, and the filtrate is discarded. The filtered precipitate is washed 5 times with deionized water, with 150 mL used each time, to remove residual impurities and unreacted silver ions, and then washed 2 times with absolute ethanol, with 100 mL used each time, to promote drying. The washed precipitate is transferred to a vacuum drying oven and dried at 80 °C for 12 h to obtain dry silver-doped titanium dioxide precursor powder. The dried precursor powder is placed in a high-temperature tube furnace and heated to 550 °C at a heating rate of 5 °C / min and kept warm in an air atmosphere for 4 h. After sintering is completed, it is naturally cooled to room temperature, and doped titanium dioxide particles are obtained after grinding and dispersion.

[0085] The average diameter of the doped titanium dioxide particles loaded with silica in this embodiment is 260 nm.

[0086] The heat stabilizer in this embodiment is Irganox 1010 or benzotriazole.

[0087] The curing agent in this embodiment is triethylenetetramine or di-tert-butyl peroxide.

[0088] A preparation method of a pan antibacterial material in this embodiment includes the following steps:

[0089] S1. Place the surface-modified boron nitride nanotube-coated silver filler, silica-loaded doped titanium dioxide particles, and polyethylene glycol in a 500 mL beaker, add half of the ethanol, place the beaker on a magnetic stirrer, and stir at a stirring rate of 700 rpm for 60 min until a uniform dispersion of nanomaterials is formed. Add polytetrafluoroethylene powder, silicone resin, and heat stabilizer to the above nanomaterial dispersion, continue stirring at a rate of 600 rpm, gradually add the remaining half of the ethanol, and stir for 90 min to ensure that the polytetrafluoroethylene and silicone resin are fully mixed and uniformly dispersed, obtaining a uniformly mixed solution.

[0090] S2. Heat the uniformly mixed solution obtained in step S1 to 60 °C, heat it at a heating rate of 5 °C / min, and maintain constant temperature stirring for 90 min to promote solvent evaporation and form a high-viscosity coating slurry. After the slurry is formed, slowly add the curing agent and continue stirring at a stirring rate of 600 rpm for 60 min to ensure that the curing agent is fully mixed and uniformly dispersed with the slurry.

[0091] S3. Coat the obtained slurry on the surface of a clean and dry cookware substrate by spraying or scraping, control the coating thickness at 50 μm. After coating, place the cookware in an oven at 80 °C and keep it warm for 60 min to preliminarily dry the coating. Then transfer the cookware to a high-temperature oven, heat it to 300 °C at a heating rate of 10 °C / min, and keep it warm for 4 h to complete the curing and attachment process of the coating. Let the cured cookware cool naturally to room temperature, and finally obtain a cookware antibacterial material.

[0092] Comparative Example 1

[0093] It is basically the same as Example 1, except that the boron nitride nanotube-coated silver filler is not subjected to surface modification treatment.

[0094] Comparative Example 2

[0095] It is basically the same as Example 1, except that the boron nitride nanotubes are not coated with silver, but directly subjected to surface modification treatment with boron nitride nanotubes.

[0096] Comparative Example 3

[0097] It is basically the same as Example 1, except that the cookware material does not add the surface-modified boron nitride nanotube-coated silver filler.

[0098] Comparative Example 4

[0099] It is basically the same as Example 1, except that the doped titanium dioxide particles are not loaded with silica.

[0100] Comparative Example 5

[0101] It is basically the same as Example 1, except that silver nitrate was not added during the preparation of the doped titanium dioxide particles. Therefore, the titanium dioxide particles are not doped with silver, but silica is still loaded on the surface of the titanium dioxide particles.

[0102] Comparative Example 6

[0103] It is basically the same as Example 1, except that the doped titanium dioxide particles loaded with silica were not added during the preparation of the cookware material.

[0104] Performance test:

[0105] Wear resistance: The wear resistance of the cookware material was evaluated using a universal friction and wear testing machine (MFT-5000). The friction coefficient and wear rate were used as the main evaluation criteria. During the test, a reciprocating linear motion mode was adopted, and the test parameters were set as a loading force of 10 N, a frequency of 1 Hz, and a test duration of 10 minutes. The counter material was a silicon nitride ceramic ball with a diameter of 9.525 mm. After the test, the wear marks on the coating surface were observed using an MFP-D three-dimensional profiler, the morphological characteristics of the wear marks were analyzed, and the wear volume was calculated. Finally, the wear rate W was obtained to comprehensively measure the performance of the cookware material in terms of wear resistance.

[0106] To comprehensively evaluate the antibacterial properties of the cookware wear-resistant material, the test was carried out in two parts: quantitative analysis and qualitative analysis. The experimental object was the sample film prepared from the cookware material. The sample film was cut from the surface of the cookware material in equal proportion or prepared by processing the cookware material to ensure that the test results could accurately reflect the antibacterial properties of the material. In the quantitative analysis, Escherichia coli and Staphylococcus aureus were selected as the test strains. Before the experiment, liquid and solid media were prepared, and the experimental instruments and test sample films were sterilized by high-temperature and high-pressure treatment to ensure a sterile environment. Subsequently, the strains were activated, a bacterial suspension with a concentration of 2.5×10 5 CFU / mL was prepared, and the bacterial suspension concentration was adjusted by the ten-fold dilution method and then inoculated into the liquid medium. At the same time, the test sample film was added, and the mixture was shaken and cultured for 8-10 hours under suitable conditions. Then, 100 μL of the bacterial liquid was taken for gradient dilution until it was diluted to 10 - 4CFU / mL concentration range, and spread the diluted bacterial solution on the surface of the agar medium, incubate at 37°C for 24 hours, observe the colony growth and count the number of colonies. By calculating the total number of colonies in the inoculated bacterial solution, the antibacterial performance of the material is quantified. In the qualitative analysis, after the same preliminary experimental preparations as in the quantitative analysis, spread the diluted bacterial solution evenly on the surface of the solid medium, and place a 2 cm diameter sample film of the cookware material on the spread medium surface. After incubating at 37°C for 24 hours, observe the size of the inhibition zone around the sample film, and evaluate the antibacterial ability of the material through the diameter of the inhibition zone. Finally, calculate the inhibition rate by counting the total number of colonies in the inoculated bacterial solution, and characterize the antibacterial performance of the cookware material with the formula inhibition rate (%) = [(total number of colonies in the control group - total number of colonies in the sample group) / total number of colonies in the control group] × 100%. This test method combines quantitative and qualitative analysis, can comprehensively and systematically characterize the antibacterial performance of the cookware material, and provides a scientific basis for the practical application of the material.

[0107] The properties of the cookware materials of Examples 1-4 and Comparative Examples 1-6 are summarized in Table 1.

[0108] Table 1 Summary of the properties of the cookware materials of Examples 1-4 and Comparative Examples 1-6

[0109]

[0110] The main difference between Comparative Example 1 and Example 1 is that the silver-coated boron nitride nanotube filler was not surface-modified. As can be seen from the table, in Example 1, the friction coefficient is relatively low (0.12), and the wear rate is small (8.0 × 10 -5 mm 3 / N·m), while the friction coefficient (0.15) and wear rate (12.0 × 10 -5 mm 3 / N·m) of Comparative Example 1 increased significantly. This indicates that surface modification of the silver-coated boron nitride nanotube filler can significantly improve the wear resistance of the material. This is because the unmodified filler has poor dispersibility and is prone to aggregation during friction, resulting in an increase in the friction coefficient and wear rate. In terms of antibacterial performance, the inhibition rate of Example 1 is 98.5%, and the diameter of the inhibition zone is 18.0 mm, while the inhibition rate of Comparative Example 1 is only 95.0%, and the diameter of the inhibition zone is 15.0 mm. This shows that surface modification treatment not only improves the dispersibility of the filler but also effectively enhances the release efficiency of silver ions, thereby enhancing the antibacterial ability of the material.

[0111] The main difference between Comparative Example 2 and Example 1 is that boron nitride nanotubes were not coated with silver but directly surface-modified. As can be seen from the table, the friction coefficient (0.13) and wear rate (8.5× 10 -5 mm3 / N·m) is higher than that of Example 1. This indicates that silver-coated boron nitride nanotubes are more effective in improving wear resistance. In terms of antibacterial performance, the antibacterial rate of Comparative Example 2 is 96.5%, and the diameter of the antibacterial zone is 16.5 mm, both of which are lower than those of Example 1. This is because the antibacterial property of boron nitride nanotubes without silver coating mainly relies on surface modification treatment, lacking the broad-spectrum antibacterial effect of silver, resulting in a decline in antibacterial performance.

[0112] The main difference between Comparative Example 3 and Example 1 is that the cookware material does not add surface-modified silver-coated boron nitride nanotube filler. As can be seen from the table, the friction coefficient (0.20) and wear rate (15.0 × 10 -5 mm 3 / N·m) of Comparative Example 3 are significantly higher than the friction coefficient (0.12) and wear rate (8.0 × 10 -5 mm 3 / N·m) of Example 1. This shows that the surface-modified silver-coated boron nitride nanotube filler plays a key role in improving wear resistance. This is because without this filler, the wear resistance of the material significantly decreases, and large deformation and wear are prone to occur during the friction process. In terms of antibacterial performance, the antibacterial rate of Comparative Example 3 is only 90.0%, and the diameter of the antibacterial zone is only 12.0 mm, far lower than that of Example 1. This indicates that the silver-coated boron nitride nanotube filler is crucial for improving antibacterial performance, as the combined action of the broad-spectrum antibacterial effect of silver and the dispersibility of the filler can achieve a higher antibacterial effect.

[0113] The main difference between Comparative Example 4 and Example 1 is that the doped titanium dioxide particles are not loaded with silica. As can be seen from the table, the friction coefficient (0.12) and wear rate (8.5 × 10 -5 mm 3 / N·m) of Comparative Example 4 are slightly higher than those of Example 1. This shows that the doped titanium dioxide particles loaded with silica have a certain effect on improving wear resistance. This is because silica loading can further improve the dispersibility and strengthening effect of the filler, thereby reducing the friction coefficient and wear rate. In terms of antibacterial performance, the antibacterial rate of Comparative Example 4 is 98.0%, and the diameter of the antibacterial zone is 17.0 mm, slightly lower than that of Example 1. This is because the doped titanium dioxide particles loaded with silica can provide additional antibacterial active sites, thereby enhancing the release efficiency of silver ions, and the antibacterial performance slightly decreases when not loaded with silica.

[0114] The main difference between Comparative Example 5 and Example 1 is that the doped titanium dioxide particles do not add silver nitrate, so the titanium dioxide particles are not doped with silver, but still loaded with silica on their surface. As can be seen from the table, the friction coefficient (0.13) and wear rate (9.0 × 10 -5 mm 3 / N·m) is slightly higher than that of Example 1. This indicates that the silver-doped titanium dioxide particles contribute to the wear resistance to a certain extent. This is because silver doping can improve the mechanical strength and stability of the filler, while the effect of the particles loaded with only silica is slightly weaker. In terms of antibacterial performance, the antibacterial rate of Comparative Example 5 is 97.5%, and the diameter of the antibacterial zone is 16.0 mm, which is lower than that of Example 1. This shows that silver doping plays an important role in enhancing antibacterial performance, because silver ions can significantly enhance the antibacterial ability of the material, while the titanium dioxide particles without silver doping only rely on the role of silica, resulting in a decrease in antibacterial effect.

[0115] The main difference between Comparative Example 6 and Example 1 is that the doped titanium dioxide particles loaded with silica are not added to the cookware material. As can be seen from the table, the friction coefficient (0.25) and wear rate (18.0 × 10 -5 mm 3 / N·m) of Comparative Example 6 are significantly higher than those of Example 1. This indicates that the doped titanium dioxide particles loaded with silica are crucial for improving wear resistance. This is because without this filler, the material lacks enhancement during the friction process, resulting in a significant increase in wear. In terms of antibacterial performance, the antibacterial rate of Comparative Example 6 is only 85.0%, and the diameter of the antibacterial zone is only 10.0 mm, which is much lower than that of Example 1. This is because after the doped titanium dioxide particles loaded with silica are not added, the material loses the main antibacterial active ingredient, resulting in a significant decrease in antibacterial performance.

[0116] In summary, the synergistic effect between components is the key to achieving excellent performance of the cookware material. The modified boron nitride nanotube-coated silver filler improves the dispersibility and interfacial bonding force of the filler through surface modification. At the same time, the lubricating effect and antibacterial characteristics of silver significantly enhance the wear resistance and antibacterial performance of the material; the silver-doped titanium dioxide particles further improve their dispersion stability and antibacterial active sites through the loading of silica, thereby enhancing the overall antibacterial effect of the material; the silica loading not only improves the mechanical properties of the particles but also plays an important auxiliary role in improving antibacterial efficiency and wear resistance. Through the synergistic effects of "strength enhancement", "lubrication and wear reduction", and "broad-spectrum antibacterial", these components not only significantly reduce the friction coefficient and wear rate but also achieve a significant increase in the antibacterial rate and the diameter of the antibacterial zone, ultimately endowing the material with excellent comprehensive performance. This shows that reasonable design and optimization of the synergistic effect of multi-components are the core strategies for achieving high-performance cookware materials.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that all equivalent structural transformations made under the concept of the present invention by using the content of the specification and drawings of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A cookware antibacterial material, characterized in that: The composition comprises the following components in parts by weight: 0.5-1.5 parts of surface modified boron nitride nanotube coated silver filler, 3-8 parts of doped titanium dioxide particles loaded with silicon dioxide, 25-35 parts of polytetrafluoroethylene, 10-15 parts of organic silicone resin, 1.0-3.0 parts of thermal stabilizer, 0.5-1 parts of polyethylene glycol 400, 45-55 parts of ethanol, and 1-3 parts of curing agent; The surface-modified boron nitride nanotube-coated silver filler is obtained by surface-modifying the boron nitride nanotube-coated silver filler with KH-550; The doping in the silica-loaded doped titanium dioxide particles is specifically silver doping; The preparation method of the boron nitride nanotubes is as follows: 5.0-8.0 parts of amorphous boron powder are weighed by weight and placed in a graphite crucible of a high-temperature inert atmosphere tube furnace, the inside of the tube furnace is evacuated to vacuum, the vacuum degree is controlled at -0.08-0.1 MPa, and then argon is introduced for protection, the flow rate is controlled at 200-300 mL / min, the furnace temperature is heated to 800-1100°C at a heating rate of 5-10°C / min, and the temperature is kept for 30-60 min, the boron powder is activated, and after the activation treatment is completed, the furnace temperature is continued to be heated to 1200-1400°C at a heating rate of 10-20°C / min, and 200-400 mL / min of ammonia is introduced for nitridation reaction at the same time, and the insulation time is 2-4 hours. After the reaction is completed, the introduction of ammonia is stopped, and 200-300 mL / min of ammonia is introduced. mL / min of argon, and lower the furnace temperature to room temperature at a cooling rate of 5~10℃ / min to obtain a preliminarily generated boron nitride product. The preliminarily generated product is taken out and placed in a beaker, and 100~150 mL of 0.1~0.5 mol / L dilute hydrochloric acid solution is added. The product is placed on a magnetic stirrer and stirred at a stirring rate of 300~500 rpm for 30~60 min. The product is acid-washed. The product after acid washing is washed with deionized water for 3~5 times, each time with an amount of 100~150 mL, until the pH of the washing solution is close to neutral, and then washed with anhydrous ethanol for 1~2 times, each time with an amount of 50~100 mL, to complete further washing. The washed product is transferred to a vacuum drying oven and dried at 60~80℃ for 12~24h to obtain dry boron nitride nanotubes.

2. The antibacterial material for cookware according to claim 1, characterized in that: The preparation method of the surface modified boron nitride nanotube coated silver filler is as follows: by weight, 10 to 18 parts of boron nitride nanotube coated silver filler are added to 100 to 150 parts of anhydrous ethanol, stirred at a stirring rate of 500 to 700 rpm for 30 to 40 minutes, and after the stirring is completed, ultrasonic treatment is performed to obtain a suspension, wherein the parameters of the ultrasonic treatment are: ultrasonic power of 200 to 300 W, frequency of 40 to 50 kHz, and ultrasonic time of 20 to 30 minutes, and then 1.0 to 2.5 parts of KH-550 are continued to be added, and then at a temperature of 60 to 80 ° C, stirring is continued at a stirring rate of 300 to 500 rpm for 20 to 30 minutes. After the stirring is completed, the reaction solution is separated by vacuum filtration, the filter residue is collected, and the filter residue is transferred to a beaker, and 100 to 150 The mixture was washed 3 to 4 times with 10 mL of anhydrous ethanol, each time with a stirring time of 5 to 10 min, to remove unreacted KH-550 and impurities. After the washing was completed, the filter residue was filtered and placed in a vacuum drying oven, and dried at 60 to 70 ° C for 10 to 12 h to obtain a surface-modified boron nitride nanotube-coated silver filler.

3. The antibacterial material for cookware according to claim 2, characterized in that: The preparation method of the boron nitride nanotube-coated silver filler is as follows: 3.0-4.5 parts of boron nitride nanotubes are weighed in parts by weight and placed in a 250 mL beaker, 100-150 mL of anhydrous ethanol is added, the beaker is placed on a magnetic stirrer, and stirred at a stirring rate of 500-700 rpm for 20-30 minutes, then the beaker is placed in an ultrasonic cleaner, and ultrasonic treatment is performed for 20-30 minutes under the conditions of an ultrasonic power of 200-300 W and a frequency of 40-50 kHz to form a boron nitride nanotube suspension, 1.0-1.5 parts of silver nitrate are weighed and dissolved in 100-150 mL of deionized water to obtain a silver nitrate solution, the boron nitride nanotube suspension is added to the silver nitrate solution, and the beaker is placed on a magnetic stirrer and stirred at a stirring rate of 500-700 rpm for 30-40 min, transfer the mixed solution to a vacuum ultrasonic device, and perform ultrasonic treatment under a vacuum pressure of -0.08-0.1 MPa, with an ultrasonic power of 200-300 W, a frequency of 40-50 kHz, and a treatment time of 20-30 min. After the vacuum ultrasonic treatment, return to normal pressure, heat the mixed solution to 50-60 °C, and then slowly add 0.1 mol / L glucose solution at a drop rate of 1-2 mL / min. The total volume is controlled at 20-30 mL. Continue to maintain constant temperature stirring for 60-90 min until the color of the solution gradually changes from colorless to light gray. After the reaction solution is cooled, separate it by vacuum filtration, collect the filter residue, and wash it 2-3 times with deionized water, each time with 100-150 mL, and then wash it 1-2 times with anhydrous ethanol, each time with 50-100 mL, the washed filter residue was transferred to a vacuum drying oven and dried at 60-70 °C for 10-12 h to obtain boron nitride nanotube-coated silver filler.

4. The antibacterial material for cookware according to claim 1 or 2, characterized in that: The average diameter of the surface modified boron nitride nanotube coated silver filler is 15-65nm, and the average length is 550-1350nm.

5. The antibacterial material for cookware according to claim 1, characterized in that: The preparation method of the silica-loaded doped titanium dioxide particles is as follows: by weight, 5.0-7.0 parts of doped titanium dioxide particles are weighed and placed in a 250 mL beaker, 100-150 mL of anhydrous ethanol is added, the beaker is placed on a magnetic stirrer, and stirred at a stirring rate of 300-500 rpm for 30-40 min until a uniform dispersion is formed, 3.0-5.0 parts of tetraethyl orthosilicate are weighed and slowly added to the above dispersion, the dropping rate is controlled to 1.0-2.0 mL / min, and the stirring rate is maintained at 400-600 rpm, and stirring is continued for 30-60 min until the tetraethyl orthosilicate is completely mixed, and 0.1 mol / L hydrochloric acid solution is slowly added to the resulting mixed solution, the dropping rate is 0.5-1.0 mL / min, and the stirring rate is maintained at 300-500 rpm. rpm, adjust the solution pH to 2.0-4.0, and continue stirring for 30-60 minutes to complete the hydrolysis process of ethyl orthosilicate, transfer the resulting solution to a water bath at 80-90°C, heat and maintain constant temperature stirring for 60-90 minutes to promote the deposition of silicon dioxide on the surface of doped titanium dioxide particles. After the reaction is completed, the reaction solution is naturally cooled to room temperature, the resulting precipitate is separated by vacuum filtration, the filtrate is discarded, and the precipitate is washed with deionized water 3-5 times, each time with an amount of 100-150 mL, to remove unreacted impurities and by-products, and then washed with anhydrous ethanol 1-2 times, each time with an amount of 50-100 mL, the washed precipitate is transferred to a vacuum drying oven and dried at 60-80°C for 8-12h to obtain dry silica-loaded doped titanium dioxide particles. The dried sample is placed in a tubular furnace and heated to 400-500°C at a heating rate of 3-5°C / min and kept warm in an air atmosphere for 2-4 hours. After the sintering treatment of the material is completed, silica-loaded doped titanium dioxide particles are obtained.

6. The antibacterial material for cookware according to claim 5, characterized in that: The preparation method of the doped titanium dioxide particles is as follows: 10.0-15.0 parts of tetrabutyl titanate are weighed by weight and placed in a 250 mL beaker, 50-100 mL of anhydrous ethanol is added, the beaker is placed on a magnetic stirrer, and stirred at a stirring rate of 400-600 rpm for 30-40 minutes until a uniform tetrabutyl titanate solution is formed; 0.5-2.0 parts of silver nitrate are weighed and dissolved in 20-50 mL of deionized water to obtain a silver nitrate solution; the silver nitrate solution is slowly dripped into the tetrabutyl titanate solution at a dripping rate of 1.0-2.0 mL / min, while the stirring rate is maintained at 500-700 rpm, and the stirring is continued for 30-60 minutes to ensure that the silver ions are uniformly dispersed in the tetrabutyl titanate solution, and 0.1 mol / L of hydrochloric acid solution is slowly dripped into the above-mentioned mixed solution at a dripping rate of 1.0-2.0 mL / min, and the stirring rate is maintained at 400-600 rpm. rpm, adjust the solution pH to 1.0-3.0 to promote the hydrolysis reaction of tetrabutyl titanate. After the dropwise addition is completed, the resulting solution is transferred to a reactor and heated at 80-100°C for 6-12 hours to complete the formation of titanate gel and the silver ion doping process. After the reaction is completed, the reactor is naturally cooled to room temperature. The resulting product is separated by vacuum filtration, and the filtrate is discarded. The filtered precipitate is washed with deionized water for 3-5 times, each time with an amount of 100-150 mL to remove residual impurities and unreacted silver ions, and then washed with anhydrous ethanol 1-2 times, each time with an amount of 50-100 mL to promote drying. The washed precipitate is transferred to a vacuum drying oven and dried at 60-80°C for 8-12 hours to obtain a dry silver-doped titanium dioxide precursor powder. The dried precursor powder is placed in a high-temperature tube furnace, heated to 450~550℃ at a heating rate of 3~5℃ / min, and kept warm in an air atmosphere for 2~4h. After sintering, it is naturally cooled to room temperature, and doped titanium dioxide particles are obtained after grinding and dispersion.

7. The antibacterial material for cookware according to claim 1 or 5, characterized in that: The average diameter of the silicon dioxide-loaded doped titanium dioxide particles is 120-250 nm.

8. The antibacterial material for cookware according to claim 1, characterized in that: The thermal stabilizer is Irganox1010 or benzotriazole; The curing agent is triethylenetetramine or di-tert-butyl peroxide.

9. The method for preparing an antibacterial material for cookware according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Place the surface-modified boron nitride nanotubes coated with silver fillers and the silica-loaded doped titanium dioxide particles and polyethylene glycol in a 500 mL beaker, add half of the ethanol, place the beaker on a magnetic stirrer, and stir at a stirring rate of 500-700 rpm for 30-60 min until a uniform nanomaterial dispersion is formed, add polytetrafluoroethylene powder, silicone resin and thermal stabilizer to the above nanomaterial dispersion, continue stirring at a rate of 400-600 rpm, gradually add the remaining half of the ethanol, and stir for 60-90 min to ensure that the polytetrafluoroethylene and silicone resin are fully mixed and evenly dispersed to obtain a uniform mixed solution; S2. The uniform mixed solution obtained in step S1 is heated to 50-60°C at a heating rate of 2-5°C / min, and the mixture is stirred at a constant temperature for 60-90 min to promote the volatilization of the solvent and form a high-viscosity coating slurry. After the slurry is formed, the curing agent is slowly added, and the stirring is continued for 30-60 min at a stirring rate of 400-600 rpm to ensure that the curing agent and the slurry are fully mixed; S3. Apply the obtained slurry on the clean and dry surface of the cookware substrate by spraying or scraping. The coating thickness is controlled at 20~50μm. After coating, place the cookware in an oven at 60~80℃ and keep it warm for 30~60min to preliminarily dry the coating. Then transfer the cookware to a high-temperature oven and heat it to 250~300℃ at a heating rate of 5~10℃ / min and keep it warm for 2~4h to complete the curing and adhesion process of the coating. After curing, naturally cool the cookware to room temperature to finally obtain an antibacterial material for cookware.

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