A glass baking tray with non-stick function and its production method

Abstract

The present invention discloses a glass baking tray with a non-stick function and its production method, belonging to the technical field of kitchen utensils. Through the combination of hydroxyl groups on the surface of nano-Al 2 O 3 powder and ethoxy groups on the modified silicone resin, a ceramic-modified silicone resin primer is obtained, which has excellent adhesion and heat conduction capabilities; impregnating epoxy resin on antibacterial ceramic powder and carbonizing it can effectively prevent food from sticking to the glass baking tray and inhibit the growth of bacteria on the surface. The carbon skeleton formed by carbonization can effectively disperse stress through a relative slip mechanism, enhance the wear resistance of the glass baking tray, extend its service life, and avoid stress concentration caused by the difference in thermal conductivity between the topcoat and the primer during temperature changes, thereby ensuring uniform heating of the glass baking tray and extending its service life; many metal skeletons with adsorption capabilities are in-situ generated on the surface of the modified curing agent, which can adsorb VOCs during the production process of the glass baking tray and avoid environmental impact.

Description

Technical Field

[0001] The present invention belongs to the technical field of kitchen utensils, and particularly relates to a glass baking tray with a non-stick function and a production method thereof. Background Art

[0002] Glass products play a crucial role in people's daily lives. Especially in the kitchen environment, glass containers are everywhere. Due to the non-toxic natural property and transparent characteristics of glass baking trays, they can significantly enhance the visual appeal of food, increase the appetite of diners, and make the dishes more attractive. Therefore, they are widely used in the catering field. However, glass baking trays also have certain limitations in the process of use. Since food is prone to adhere to the surface of the glass baking tray, especially during baking operations, this adhesion phenomenon makes cleaning difficult, thus affecting the usability of the glass container. In addition, compared with metal baking trays, the heat conduction performance of glass baking trays is relatively poor. Therefore, before formal use, it usually needs to be preheated for a period of time to ensure that the baking tray can be evenly heated and reach the required cooking temperature.

[0003] A Chinese patent with the publication number CN108976941B discloses a highly wear-resistant non-stick coating for cooking utensils and its preparation method, including a surface layer coating and a non-surface layer coating. The coating includes: polytetrafluoroethylene emulsion, binder resin, wear-resistant resin, pigment, filler, and additive. The components of the surface layer coating and the non-surface layer coating are the same, but the component contents are different. Specifically, the content of the binder resin in the non-surface layer coating is higher than that in the surface layer coating. This design aims to enhance its adhesion performance to the glass substrate. However, due to the different component contents in the two layers of coatings, when heated, the heat transfer between the coatings will be uneven, thus causing stress concentration. This stress concentration may lead to peeling or falling off between the coatings, affecting the overall performance and durability of the coating. Summary of the Invention

[0004] The purpose of the present invention is to provide a glass baking tray with a non-stick function. By combining the hydroxyl groups on the surface of nano-Al 2 O 3 powder with the ethoxy groups on the modified silicone resin, a ceramic-modified silicone resin primer is obtained, which has excellent adhesion ability and heat conduction ability, avoiding the primer from being fragile and falling off. Impregnate epoxy resin on the antibacterial ceramic powder, and then carry out carbonization treatment to construct a porous and relatively flexible carbon skeleton structure on the surface layer of the antibacterial ceramic powder, and fill it into polytetrafluoroethylene to obtain a modified topcoat. The spatial structure of the carbon skeleton can effectively disperse stress through a relative slip mechanism when facing stress, solving the problem that when the temperature changes, due to the difference in the thermal conductivity between the topcoat and the primer, stress concentration is caused, further leading to coating peeling.

[0005] The object of the present invention can be achieved by the following technical solutions:

[0006] A production method of a glass baking tray with non-stick function is prepared by the following steps:

[0007] Step 1: Add 5-hydroxyisophthalic acid and epichlorohydrin into a reaction kettle, stir at 50-60 °C and 400-500 r / min for 30-50 min, add 50-60 wt% potassium hydroxide solution and tetrabutylammonium bromide into the reaction kettle, stir at 50-60 °C and 400-500 r / min for 24-26 h, perform rotary evaporation to remove the excessive epichlorohydrin in the mixture to obtain a crude product; extract the crude product with ethyl acetate, wash it with deionized water, dry it in anhydrous sodium sulfate for 24-26 h, filter, remove ethyl acetate from the filtrate by rotary evaporation, and purify it by column chromatography using dichloromethane as the eluent to obtain a resin intermediate.

[0008] Step 2: Add 3-aminopropylmethyldiethoxysilane, deionized water and tetrahydrofuran into a reaction kettle, heat to 70-80 °C and stir at 400-500 r / min for 24-26 h, add the resin intermediate into the reaction kettle, stir at 70-80 °C and 400-500 r / min for 10-12 h, perform suction filtration, wash the filter cake with deionized water and absolute ethanol respectively for 2-3 times, and dry it in vacuum at 60-80 °C for 16-18 h to obtain a modified silicone resin.

[0009] Step 3: Add nano-Al 2 O 3 powder with a particle size of 18-20 nm and deionized water into a reaction kettle, perform ultrasonic dispersion for 40-60 min, stir at 50-60 °C and 400-500 r / min for 40-50 min, add the modified silicone resin powder into the reaction kettle, continue to stir for 10-12 h, filter, wash the filter cake with deionized water and absolute ethanol respectively for 2-3 times, and dry it in vacuum at 60-80 °C for 16-18 h to obtain a ceramic-modified silicone resin primer.

[0010] Step 4: Add silicon carbide ceramic powder with a particle size of 30-40 μm, sodium citrate and ethylene glycol into a reaction kettle, stir at 40-50 °C and 500-600 r / min for 20-30 min, add sodium acetate into the reaction kettle, heat to 80-90 °C, continue to stir for 2-3 h, add nano-zinc powder into the reaction kettle, and continue to stir for 2-3 h to obtain an antibacterial ceramic powder.

[0011] Step 5: Add bisphenol A epoxy resin powder with a particle size of 20 - 30 μm, methyltetrahydrophthalic anhydride, and triphenol into a reaction kettle, stir for 40 - 60 min under the conditions of 20 - 25 °C and 500 - 600 r / min, add antibacterial ceramic powder into the reaction kettle, carry out vacuum impregnation for 3 - 4 h, filter, wash the filter cake with deionized water 2 - 3 times, vacuum dry at 60 - 80 °C for 1 - 2 h, transfer to a muffle furnace, introduce nitrogen for protection, heat to 350 - 370 °C and hold for 2 - 3 h, heat to 500 - 550 °C and hold for 2 - 3 h, naturally cool, filter, wash the filter cake with deionized water 2 - 3 times, vacuum dry at 60 - 80 °C for 1 - 2 h to obtain antibacterial wear-resistant agent powder; mix the antibacterial wear-resistant agent powder and polytetrafluoroethylene powder evenly according to a mass ratio of 1:3 to obtain a modified topcoat.

[0012] Step 6: Add polyetheramine and deionized water into a reaction kettle, stir for 10 - 12 min under the conditions of 40 - 50 °C and 400 - 500 r / min, add 4-hydroxybutyl vinyl ether, phthalic acid biphenyl, and deionized water, stir and mix for 1 - 2 h under the conditions of 70 - 80 °C and 400 - 500 r / min, add ferric sulfate into the reaction kettle, continue to stir and react for 5 - 6 h, dropwise add to the reaction kettle at a speed of 40 - 45 drops / min, continue to stir and react for 3 - 4 h, filter, wash the filter cake with deionized water and absolute ethanol 2 - 3 times respectively, vacuum dry at 60 - 80 °C for 16 - 18 h to obtain a modified curing agent.

[0013] Step 7: Place high borosilicate glass in the kiln furnace track, heat to 800 - 850 °C to make it soften, transfer the softened high borosilicate glass to a baking pan mold, carry out internal heat bending molding, cool to 40 - 50 °C to obtain a glass substrate, mix ceramic modified silicone resin primer and modified curing agent according to a mass ratio of 7:1, spray it on the glass substrate with a spray gun, with the coating thickness of 450 - 500 μm, place it in an oven at 80 - 90 °C and dry for 15 - 20 min to obtain a primer coating, the thickness of the primer coating is 450 - 500 μm, then spray the modified topcoat on the primer coating of the glass substrate with a spray gun, place it in an oven at 80 - 90 °C and dry for 15 - 20 min, naturally cool to obtain a surface coating, the thickness of the surface coating is 350 - 400 μm, heat to 320 - 330 °C, hold for 20 - 25 min, naturally cool to obtain a glass baking pan with a non-stick function.

[0014] Further, the dosage ratio of 5-hydroxyisophthalic acid, epichlorohydrin, potassium hydroxide, and tetrabutylammonium bromide in Step 1 is 40 - 50 g : 50 - 60 mL : 70 - 80 mL : 20 - 30 g.

[0015] Further, the dosage ratio of 3-aminopropylmethyldiethoxysilane, deionized water, tetrahydrofuran, and resin intermediate in step two is 15-20 g: 200-300 mL: 30-40 mL: 20-30 g.

[0016] Further, in step three, the dosage ratio of nano-Al 2 O 3 powder, deionized water, and modified silicone resin powder is 5-6 g: 200-300 mL: 15-20 g.

[0017] Further, in step four, the dosage ratio of silicon carbide ceramic powder, sodium citrate, ethylene glycol, sodium acetate, and nano-zinc powder is 10-12 g: 2-3 g: 200-300 mL: 12-14 g: 20-25 g.

[0018] Further, in step five, the dosage ratio of bisphenol A epoxy resin powder, methyltetrahydrophthalic anhydride, triphenol, and antibacterial ceramic powder is 20-25 g: 50-60 mL: 10-12 g.

[0019] Further, in step six, the dosage ratio of polyetheramine, deionized water, 4-hydroxybutyl vinyl ether, biphenyl dicarboxylic acid, deionized water, and ferric sulfate is 10-12 kg: 5-6 L: 8-10 kg: 10-11 kg: 2-3 L: 15-20 g.

[0020] Advantages of the present invention:

[0021] 1. The surface of the glass baking tray prepared by the present invention is coated with a modified topcoat. The modified topcoat is based on polytetrafluoroethylene, and its chemical properties are very stable. It is not easy to form new chemical bonds with proteins, sugar molecules, etc. in food. Therefore, food molecules are not likely to undergo chemical reactions with the coating surface, thus avoiding adhesion between food and the coating and making the baking tray easy to clean. Moreover, the primer coating and surface coating of the glass baking tray have the characteristics of high temperature resistance and stability, can withstand high temperatures without melting and deforming easily, have excellent thermal conductivity to ensure uniform heating of the baking tray, have good wear resistance and antibacterial properties on the surface of the glass baking tray, and do not produce a large amount of volatile organic compounds (VOCs) during the production and preparation process.

[0022] 2. For the ceramic-modified silicone resin primer of the present invention, the hydroxyl groups on the surface of nano-Al 2 O 3 powder combine with the ethoxy groups on the modified silicone resin, enabling it to be evenly dispersed in the modified silicone resin. The silicone resin has excellent adhesion ability, and the silicon-oxygen bond (Si-O-Si) in the silicone resin has a high bond energy, which enables it to form a strong bond with the chemical bonds on the surface of the adherend, and can prevent nano-Al 2 O 3The primer can be firmly combined with the topcoat, and nano-Al 2 O 3 can increase the heat conduction ability of the glass baking pan.

[0023] 3. The addition of the antibacterial and wear-resistant agent powder of the present invention can significantly improve the wear resistance and antibacterial property of the surface coating of the glass baking pan. By impregnating epoxy resin on the surface of the antibacterial ceramic powder and then performing carbonization treatment, a porous and relatively low-hardness carbon layer structure is constructed on the surface layer of the antibacterial ceramic powder, which can effectively disperse stress through the relative slip mechanism, avoid stress concentration caused by high temperature or other external forces, reduce crack propagation and coating peeling, thereby further enhancing the wear resistance of the glass baking pan, overcoming the defects of soft texture and easy scratching when polytetrafluoroethylene is used as the topcoat. At the same time, this design also ensures uniform heating of the baking pan, thereby extending its service life; to a certain extent, the spatial structure of the carbon skeleton can prevent the migration of zinc ions wrapped therein, thereby achieving the effect of long-term antibacterial.

[0024] 4. Many metal skeletons with adsorption ability are in-situ generated on the surface of the modified curing agent of the present invention, which can adsorb VOCs to avoid environmental impact. Benzene rings are introduced by the addition reaction of the polyetheramine polymerization chain through vinyl groups, and the metal skeletons can further increase the heat resistance of the curing agent, enabling better curing of the coating, improving the stability and service life of the curing agent. Detailed Embodiments

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] Embodiment 1: A production method of a non-stick glass baking pan is prepared through the following steps:

[0027] S1: Add 40 g of 5-hydroxyisophthalic acid and 50 mL of epichlorohydrin to the reaction kettle, stir at 50 °C and 400 r / min for 30 min, add 70 mL of 50 wt% potassium hydroxide solution and 20 g of tetrabutylammonium bromide to the reaction kettle, stir at 50 °C and 400 r / min for 24 h, perform rotary evaporation to remove the excess epichlorohydrin in the mixture to obtain a crude product; extract the crude product with ethyl acetate, wash with deionized water, dry in anhydrous sodium sulfate for 24 h, filter, remove ethyl acetate from the filtrate by rotary evaporation, and perform column chromatography purification using dichloromethane as the eluent to obtain a resin intermediate.

[0028] S2: Add 15 g of 3-aminopropylmethyldiethoxysilane, 200 mL of deionized water, and 30 mL of tetrahydrofuran into a reaction kettle, heat to 70 °C and stir for 24 h under the condition of 400 r / min. Add 20 g of resin intermediate into the reaction kettle, stir for 10 h under the condition of 70 °C and 400 r / min, carry out suction filtration, wash the filter cake twice with deionized water and absolute ethanol respectively, and dry it in vacuum at 60 °C for 16 h to obtain modified silicone resin.

[0029] Through the hydroxyl reaction of epichlorohydrin with 5-hydroxyisophthalic acid, a resin intermediate with epoxy groups is obtained, and then it combines with the amino group on 3-aminopropylmethyldiethoxysilane. The introduction of the benzene ring significantly increases the overall strength of the silicone resin.

[0030] S3: Add 5 g of nano-Al 2 O 3 powder with a particle size of 18 - 20 nm and 200 mL of deionized water into a reaction kettle, carry out ultrasonic dispersion for 40 min, stir for 40 min under the condition of 50 °C and 400 r / min. Add 15 g of modified silicone resin powder into the reaction kettle, continue to stir for 10 h, filter, wash the filter cake twice with deionized water and absolute ethanol respectively, and dry it in vacuum at 60 °C for 16 h to obtain ceramic-modified silicone resin primer.

[0031] The hydroxyl groups on the surface of nano-Al 2 O 3 powder combine with ethoxy groups, enabling it to be evenly dispersed in the silicone resin, obtaining ceramic-modified silicone resin primer, enhancing the heat conduction ability when the primer is sprayed to prepare a baking tray, and the excellent adhesion and flexibility of the silicone resin can avoid the brittleness caused by the addition of ceramics.

[0032] S4: Add 10 g of silicon carbide ceramic powder with a particle size of 30 - 40 μm, 2 g of sodium citrate, and 200 mL of ethylene glycol into a reaction kettle, stir at 40 °C and 500 r / min for 20 min. Add 12 g of sodium acetate into the reaction kettle, heat to 80 °C, continue to stir for 2 h. Add 20 g of nano-zinc powder into the reaction kettle, continue to stir for 2 h to obtain antibacterial ceramic powder.

[0033] Carboxylate the silicon carbide ceramic powder, and under hydrothermal conditions, combine with the hydroxyl groups on the surface of nano-zinc, making nano-zinc evenly loaded on the silicon carbide ceramic powder.

[0034] S5: Add 20 g of bisphenol A epoxy resin powder with a particle size of 20 - 30 μm, 50 mL of methyltetrahydrophthalic anhydride, and 10 g of triphenol into a reaction kettle. Stir for 40 min under the conditions of 20°C and 500 r / min. Then add 10 g of antibacterial ceramic powder into the reaction kettle, carry out vacuum impregnation for 3 h, filter, wash the filter cake twice with deionized water, dry it in vacuum at 60°C for 1 h, transfer it to a muffle furnace, introduce nitrogen for protection, heat it to 350°C and hold for 2 h, then heat it to 500°C and hold for 2 h, cool it naturally, filter, wash the filter cake twice with deionized water, and dry it in vacuum at 60°C for 1 h to obtain antibacterial wear-resistant agent powder; mix the antibacterial wear-resistant agent powder and polytetrafluoroethylene powder evenly according to a mass ratio of 1:3 to obtain a modified topcoat.

[0035] Impregnate the epoxy resin on the antibacterial ceramic powder, carbonize it, and form a porous and relatively soft carbon skeleton on the surface of the antibacterial ceramic powder. When used as a filler for the modified topcoat, it can increase the wear resistance of the glass baking tray, and the spatial structure of the carbon skeleton can produce relative slip when facing external forces, thereby dispersing stress.

[0036] S6: Add 10 kg of polyetheramine and 5 L of deionized water into a reaction kettle. Stir for 10 min under the conditions of 40°C and 400 r / min. Then add 8 kg of 4-hydroxybutyl vinyl ether, 10 kg of biphenyl dicarboxylic acid, and 2 L of deionized water, stir and mix them for 1 h under the conditions of 70°C and 400 r / min. Add 15 g of ferric sulfate into the reaction kettle, continue to stir and react for 5 h, then add it dropwise into the reaction kettle at a speed of 40 drops / min, continue to stir and react for 3 h, filter, wash the filter cake twice with deionized water and anhydrous ethanol respectively, and dry it in vacuum at 60°C for 16 h to obtain a modified curing agent.

[0037] Introduce a benzene ring into the polyetheramine polymer chain through an addition reaction of vinyl to improve the heat resistance of the curing agent. Traditional silicone resins are prone to generate VOC during the processing process. Many metal skeletons with adsorption ability are in-situ generated on the surface of the modified curing agent, which can adsorb VOC and avoid environmental impact.

[0038] S7: Place the borosilicate glass in the kiln roller track, heat it to 800 °C to soften it, transfer the softened borosilicate glass to a baking tray mold, perform internal heat bending to form, cool it to 40 °C to obtain a glass substrate. Mix the ceramic-modified silicone resin primer and the modified curing agent according to a mass ratio of 7:1, spray it on the glass substrate with a spray gun, place it in an 80 °C drying oven and dry for 15 min to obtain a primer coating. The thickness of the primer coating is 450 μm. Then spray the modified topcoat on the primer coating of the glass substrate with a spray gun, place it in an 80 °C drying oven and dry for 15 min, and cool it naturally to obtain a surface coating. The thickness of the surface coating is 350 μm. Heat it to 320 °C, keep it warm for 20 min, and cool it naturally to obtain a glass baking tray with non-stick function.

[0039] Example 2: A production method of a glass baking tray with non-stick function is prepared by the following steps:

[0040] S1: Add 45 g of 5-hydroxyisophthalic acid and 55 mL of epichlorohydrin to a reaction kettle, stir at 55 °C and 450 r / min for 35 min. Add 75 mL of 55 wt% potassium hydroxide solution and 25 g of tetrabutylammonium bromide to the reaction kettle, stir at 55 °C and 450 r / min for 25 h, perform rotary evaporation to remove the excess epichlorohydrin in the mixture to obtain a crude product; extract the crude product with ethyl acetate, wash it with deionized water, dry it in anhydrous sodium sulfate for 25 h, filter, remove ethyl acetate from the filtrate by rotary evaporation, and perform column chromatography purification with dichloromethane as the eluent to obtain a resin intermediate.

[0041] S2: Add 18 g of 3-aminopropylmethyldiethoxysilane, 250 mL of deionized water and 35 mL of tetrahydrofuran to a reaction kettle, heat it to 75 °C and stir at 450 r / min for 25 h. Add 25 g of the resin intermediate to the reaction kettle, stir at 75 °C and 450 r / min for 11 h, perform suction filtration, wash the filter cake with deionized water and absolute ethanol twice respectively, and dry it in vacuum at 70 °C for 17 h to obtain a modified silicone resin.

[0042] S3: Add 5.5 g of nano-Al 2 O 3 powder with a particle size of 18 - 20 nm and 250 mL of deionized water to a reaction kettle, perform ultrasonic dispersion for 50 min, stir at 55 °C and 450 r / min for 45 min. Add 18 g of the modified silicone resin powder to the reaction kettle, continue to stir for 11 h, filter, wash the filter cake with deionized water and absolute ethanol twice respectively, and dry it in vacuum at 70 °C for 17 h to obtain a ceramic-modified silicone resin primer.

[0043] S4: Add 11 g of silicon carbide ceramic powder with a particle size of 30 - 40 μm, 2.5 g of sodium citrate, and 250 mL of ethylene glycol into a reaction kettle, stir at 45 °C and 550 r / min for 25 min, add 13 g of sodium acetate into the reaction kettle, heat to 85 °C, continue stirring for 2.5 h, add 23 g of nano zinc powder into the reaction kettle, and continue stirring for 2.5 h to obtain antibacterial ceramic powder.

[0044] S5: Add 23 g of bisphenol A epoxy resin powder with a particle size of 20 - 30 μm, 55 mL of methyltetrahydrophthalic anhydride, and 11 g of triphenol into a reaction kettle, stir at 23 °C and 550 r / min for 50 min, add 11 g of antibacterial ceramic powder into the reaction kettle, perform vacuum impregnation for 3.5 h, filter, wash the filter cake with deionized water twice, dry it in vacuum at 70 °C for 1.5 h, transfer it to a muffle furnace, introduce nitrogen for protection, heat to 360 °C and hold for 2.5 h, heat to 530 °C and hold for 2.5 h, cool naturally, filter, wash the filter cake with deionized water twice, dry it in vacuum at 70 °C for 1.5 h to obtain antibacterial wear-resistant agent powder; mix the antibacterial wear-resistant agent powder and polytetrafluoroethylene powder evenly according to a mass ratio of 1:3 to obtain a modified topcoat.

[0045] S6: Add 11 kg of polyetheramine and 5.5 L of deionized water into a reaction kettle, stir at 45 °C and 450 r / min for 11 min, add 9 kg of 4-hydroxybutyl vinyl ether, 10.5 kg of biphenyl dicarboxylic acid, and 2.5 L of deionized water, stir and mix at 75 °C and 450 r / min for 1.2 h, add 18 g of ferric sulfate into the reaction kettle, continue stirring and reacting for 5.5 h, add it dropwise into the reaction kettle at a rate of 43 drops / min, continue stirring and reacting for 3.5 h, filter, wash the filter cake with deionized water and absolute ethanol twice respectively, dry it in vacuum at 70 °C for 17 h to obtain a modified curing agent.

[0046] S7: Place the borosilicate glass in the kiln furnace roller track, heat to 830 °C to make it soften, transfer the softened borosilicate glass to a baking pan mold, perform internal heat bending forming, cool to 45 °C to obtain a glass substrate, mix the ceramic-modified silicone resin primer and the modified curing agent according to a mass ratio of 7:1, spray it on the glass substrate with a spray gun, place it in an 85 °C drying oven and dry for 18 min to obtain a primer coating with a thickness of 480 μm, then spray the modified topcoat on the primer coating of the glass substrate with a spray gun, place it in an 85 °C drying oven and dry for 18 min, cool naturally to obtain a surface coating with a thickness of 380 μm, heat to 325 °C, hold for 23 min, cool naturally to obtain a glass baking pan with a non-stick function.

[0047] Example 3: A production method of a glass baking pan with a non-stick function is prepared through the following steps:

[0048] S1: Add 50 g of 5-hydroxyisophthalic acid and 60 mL of epichlorohydrin into a reaction kettle, stir for 50 min under the conditions of 60 °C and 500 r / min, add 80 mL of 60 wt% potassium hydroxide solution and 30 g of tetrabutylammonium bromide into the reaction kettle, stir for 26 h under the conditions of 60 °C and 500 r / min, perform rotary evaporation to remove the excessive epichlorohydrin in the mixture to obtain a crude product; extract the crude product with ethyl acetate, wash it with deionized water, dry it in anhydrous sodium sulfate for 26 h, filter, remove ethyl acetate from the filtrate by rotary evaporation, and purify it by column chromatography using dichloromethane as an eluent to obtain a resin intermediate.

[0049] S2: Add 20 g of 3-aminopropylmethyldiethoxysilane, 300 mL of deionized water and 40 mL of tetrahydrofuran into a reaction kettle, heat it to 80 °C and stir for 26 h under the condition of 500 r / min, add 30 g of the resin intermediate into the reaction kettle, stir for 12 h under the conditions of 80 °C and 500 r / min, perform suction filtration, wash the filter cake with deionized water and absolute ethanol three times respectively, and dry it in vacuum at 80 °C for 18 h to obtain a modified silicone resin.

[0050] S3: Add 6 g of nano-Al 2 O 3 powder with a particle size of 18 - 20 nm and 300 mL of deionized water into a reaction kettle, perform ultrasonic treatment for 60 min, stir for 50 min under the conditions of 60 °C and 500 r / min, add 20 g of the modified silicone resin powder into the reaction kettle, continue to stir for 12 h, filter, wash the filter cake with deionized water and absolute ethanol three times respectively, and dry it in vacuum at 80 °C for 18 h to obtain a ceramic-modified silicone resin primer.

[0051] S4: Add 12 g of silicon carbide ceramic powder with a particle size of 30 - 40 μm, 3 g of sodium citrate and 300 mL of ethylene glycol into a reaction kettle, stir for 30 min under the conditions of 50 °C and 600 r / min, add 14 g of sodium acetate into the reaction kettle, heat it to 90 °C, continue to stir for 3 h, add 25 g of nano-zinc powder into the reaction kettle, and continue to stir for 3 h to obtain an antibacterial ceramic powder.

[0052] S5: Add 25 g of bisphenol A epoxy resin powder with a particle size of 20 - 30 μm, 60 mL of methyltetrahydrophthalic anhydride, and 12 g of triphenol into a reaction kettle. Stir for 60 min under the conditions of 25°C and 600 r / min. Add 12 g of antibacterial ceramic powder into the reaction kettle, carry out vacuum impregnation for 4 h, filter, wash the filter cake 3 times with deionized water, dry it in vacuum at 80°C for 2 h, transfer it to a muffle furnace, introduce nitrogen for protection, heat to 370°C and keep it warm for 3 h, then heat to 550°C and keep it warm for 3 h, cool naturally, filter, wash the filter cake 3 times with deionized water, dry it in vacuum at 80°C for 2 h to obtain antibacterial wear-resistant agent powder; mix the antibacterial wear-resistant agent powder and polytetrafluoroethylene powder evenly according to a mass ratio of 1:3 to obtain a modified topcoat.

[0053] S6: Add 12 kg of polyetheramine and 6 L of deionized water into a reaction kettle. Stir for 12 min under the conditions of 50°C and 500 r / min. Add 10 kg of 4-hydroxybutyl vinyl ether, 11 kg of biphenyl dicarboxylic acid, and 3 L of deionized water, stir and mix under the conditions of 80°C and 500 r / min for 2 h. Add 20 g of ferric sulfate into the reaction kettle, continue to stir and react for 6 h, dropwise add it into the reaction kettle at a speed of 45 drops / min, continue to stir and react for 4 h, filter, wash the filter cake 3 times with deionized water and anhydrous ethanol respectively, dry it in vacuum at 80°C for 18 h to obtain a modified curing agent.

[0054] S7: Place the borosilicate glass in the kiln furnace roller track, heat to 850°C to make it soften, transfer the softened borosilicate glass to a baking pan mold, carry out internal heat bending molding, cool to 50°C to obtain a glass substrate. Mix the ceramic-modified silicone resin primer and the modified curing agent according to a mass ratio of 7:1, spray it on the glass substrate with a spray gun, place it in a drying oven at 90°C and dry for 20 min to obtain a primer coating with a thickness of 500 μm. Then spray the modified topcoat on the primer coating of the glass substrate with a spray gun, place it in a drying oven at 90°C and dry for 20 min, cool naturally to obtain a surface coating with a thickness of 400 μm, heat to 330°C, keep it warm for 25 min, cool naturally to obtain a glass baking pan with a non-stick function.

[0055] Comparative Example 1: On the basis of Example 3, replace the modified silicone resin powder in step S3 with commercially available silicone resin powder of the same mass, and keep the other steps unchanged to prepare a glass baking pan with a non-stick function.

[0056] Comparative Example 2: On the basis of Example 3, replace the antibacterial wear-resistant agent powder in step S5 with the antibacterial ceramic powder in step S4, and keep the other steps unchanged to prepare a glass baking pan with a non-stick function.

[0057] Comparative Example 3: On the basis of Example 3, ferric sulfate was omitted in step S6, and the remaining steps remained unchanged, to prepare a non-stick glass baking pan.

[0058] In the examples and comparative examples:

[0059] 3-aminopropylmethyldiethoxysilane, 5-hydroxyisophthalic acid, epichlorohydrin, potassium hydroxide, graphene oxide powder, polyetheramine, 4-hydroxybutyl vinyl ether, and phthalic acid were purchased from Sigma-Aldrich.

[0060] Nano Al 2 O 3 powder was purchased from Qinghe Dingze Wear-resistant Materials Co., Ltd.

[0061] Borosilicate glass was purchased from Henan Yike New Materials Co., Ltd.

[0062] Silicon carbide ceramic powder was purchased from Hebei Ruihuang Metal Materials Co., Ltd.

[0063] Methyltetrahydrophthalic anhydride was purchased from Jinan Runbenxiang Chemical Co., Ltd.

[0064] Triphenol was purchased from Jinan Linsheng Chemical Co., Ltd.

[0065] Performance tests were carried out on the glass baking pans prepared in Examples 1-3 and Comparative Examples 1-3, and the results are shown in Table 1:

[0066] 1. Pencil hardness scratch test: Use a pencil scratch tester to test the hardness of the glass baking pan, and calibrate the hardness through the film hardness pencil determination method. First, install pencils with different hardnesses on the device (a total of 13 levels according to industrial standards), keep the pencil at a 45° angle to the surface of the glass baking pan, then push forward at a constant speed, and at the same time observe whether the surface of the glass baking pan is scratched by the pencil lead. When the coating is scratched, it means that the hardness of the pencil is greater than the hardness of the coating; otherwise, it means that the hardness of the pencil is lower than the hardness of the coating.

[0067] 2. Adhesion test: Refer to the standard of ISO2409 for testing to evaluate the adhesion strength of the sprayed coating to the glass baking pan.

[0068] 3. Thermal conductivity test: Measure different groups of glass baking pans with a C-THERMTCI thermal conductivity tester to evaluate the thermal conductivity of different groups of glass baking pans.

[0069] 4. Volatile organic compound test: Refer to the standard of HJ2537-2014 "Technical Requirements for Environmental Labeling Products - Waterborne Coatings" for testing to evaluate the generation amount of volatile organic compounds during the processing of the glass baking pan.

[0070] Table 1 Performance Test Results of Glass Baking Trays

[0071]

[0072] As can be seen from Table 1, for the glass baking trays with non-stick function prepared in Examples 1 - 3 of the present invention, the coating peeling area, adhesion, and the content of volatile organic compounds are significantly lower than those of the comparative examples, and the thermal conductivity is significantly better than that of the comparative examples, indicating that the glass baking trays prepared by the present invention have excellent wear resistance, thermal conductivity, and environmental friendliness.

[0073] In Comparative Example 1, the modified silicone resin powder was replaced with commercially available silicone resin powder of the same mass. Ethoxy groups were grafted on the surface of the modified silicone resin, which could combine with the hydroxyl groups on the surface of the nano - Al 2 O 3 powder surface, enabling it to be evenly dispersed in the modified silicone resin, so that it could better cooperate with the modified silicone resin to play a role, increase the heat resistance of the silicone resin, enhance the thermal conductivity when the primer was sprayed to prepare the baking tray, and the excellent adhesion and softness of the silicone resin could avoid the brittleness caused by the addition of ceramics.

[0074] In Comparative Example 2, the antibacterial and wear - resistant agent powder was replaced with antibacterial ceramic powder. By impregnating epoxy resin on the antibacterial ceramic powder and then performing carbonization treatment, a porous and relatively flexible carbon skeleton structure was constructed on the surface layer of the antibacterial ceramic powder. Without the carbon skeleton structure, the stress could not be effectively dispersed through the relative slip mechanism, resulting in a low adhesion grade, a large peeling area, and a low thermal conductivity.

[0075] In Comparative Example 3, iron sulfate was omitted, and a metal skeleton with adsorption ability could not be in - situ generated on the surface of the modified curing agent. The modified curing agent was based on polyetheramine, and benzene rings were introduced by addition reaction through vinyl groups in the polyetheramine polymerization chain, significantly improving the heat resistance of the curing agent. And the metal skeleton in - situ generated on the surface could avoid the VOC generated during the processing of the silicone resin, improve the heat resistance of the curing agent. The metal skeleton in - situ generated on the surface could further enhance the heat resistance, improve the stability and service life of the curing agent.

[0076] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non - exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0077] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for producing a glass baking tray with non-stick function, characterized in that: The steps include: The high borosilicate glass is placed in a kiln roller, heated to 800-850°C to soften it, the softened high borosilicate glass is transferred to a baking tray mold, hot-bending it, and cooling it to 40-50°C to obtain a glass substrate, a ceramic modified silicone resin primer and a modified curing agent are mixed in a mass ratio of 7:1, and sprayed on the glass substrate with a spray gun, the coating thickness is 450-500 μm, and placed in a drying oven at 80-90°C for 15-20 minutes to obtain a primer coating, and the primer coating thickness is 450-500 μm, and then the modified topcoat is sprayed on the primer coating of the glass substrate with a spray gun, and placed in a drying oven at 80-90°C for 15-20 minutes to dry, and naturally cooled to obtain a surface coating, and the surface coating thickness is 350-400 μm, and heated to 320-330°C, kept warm for 20-25 minutes, and naturally cooled to obtain a glass baking tray with a non-stick function; The modified topcoat is prepared by the following steps: The silicon carbide ceramic powder is carboxylated and combined with the hydroxyl groups on the surface of the nano-zinc to obtain the antibacterial ceramic powder loaded with the nano-zinc; Add bisphenol A epoxy resin powder with a particle size of 20-30 μm, methyltetrahydrophthalic anhydride and triphenol into a reactor, stir at 20-25°C and 500-600 r / min for 40-60 min, add antibacterial ceramic powder into the reactor, vacuum impregnate for 3-4 hours, filter, wash the filter cake with deionized water for 2-3 times, vacuum dry, transfer to a muffle furnace, pass nitrogen protection, heat to 350-370°C for 2-3 hours, heat to 500-550°C for 2-3 hours, cool naturally, filter, wash the filter cake with deionized water for 2-3 times, vacuum dry to obtain antibacterial and wear-resistant agent powder; mix the antibacterial and wear-resistant agent powder and polytetrafluoroethylene powder in a mass ratio of 1:3 to obtain a modified topcoat.

2. The method for producing a glass baking tray with non-stick function according to claim 1, characterized in that: The ceramic modified silicone resin primer is prepared by the following steps: Add nano-Al2O3 powder with a particle size of 18-20 nm and deionized water into a reactor, ultrasonicate for 40-60 min, stir at 50-60°C and 400-500 r / min for 40-50 min, add modified silicone resin powder into the reactor, continue stirring for 10-12 h, filter, wash the filter cake with deionized water and anhydrous ethanol for 2-3 times respectively, and vacuum dry to obtain a ceramic modified silicone resin primer; The usage ratio of the nano-Al2O3 powder, deionized water and modified silicone resin powder is 5-6g: 200-300mL: 15-20g.

3. The method for producing a glass baking tray with non-stick function according to claim 2, characterized in that: The modified silicone resin powder is prepared by the following steps: Add 3-aminopropylmethyldiethoxysilane, deionized water and tetrahydrofuran into a reaction kettle, heat to 70-80°C and 400-500r / min and stir for 24-26h, add the resin intermediate into the reaction kettle, stir at 70-80°C and 400-500r / min for 10-12h, filter with suction, wash the filter cake with deionized water and anhydrous ethanol for 2-3 times respectively, and vacuum dry to obtain a modified silicone resin.

4. The method for producing a glass baking tray with non-stick function according to claim 3, characterized in that: The usage ratio of the 3-aminopropylmethyldiethoxysilane, deionized water, tetrahydrofuran and resin intermediate is 15-20 g: 200-300 mL: 30-40 mL: 20-30 g.

5. The method for producing a non-stick glass baking tray according to claim 3, characterized in that: The resin intermediate is prepared by the following steps: Add 5-hydroxyisophthalic acid and epichlorohydrin to a reaction kettle, stir at 50-60° C. and 400-500 r / min for 30-50 min, add 50-60wt% potassium hydroxide solution and tetrabutylammonium bromide to the reaction kettle, stir at 50-60° C. and 400-500 r / min for 24-26 h, and perform rotary evaporation to remove excess epichlorohydrin in the mixture to obtain a crude product; extract the crude product with ethyl acetate, wash with deionized water, dry in anhydrous sodium sulfate for 24-26 h, filter, remove ethyl acetate from the filtrate by rotary evaporation, and perform column chromatography purification with dichloromethane as an eluent to obtain a resin intermediate.

6. The method for producing a glass baking tray with non-stick function according to claim 5, characterized in that: The usage ratio of the 5-hydroxyisophthalic acid, epichlorohydrin, potassium hydroxide and tetrabutylammonium bromide is 40-50g:50-60mL:70-80mL:20-30g.

7. The method for producing a non-stick glass baking tray according to claim 1, characterized in that: The dosage ratio of the bisphenol A epoxy resin powder, methyltetrahydrophthalic anhydride, triphenol and antibacterial ceramic powder is 20-25g: 50-60mL: 10-12g.

8. The method for producing a non-stick glass baking tray according to claim 1, characterized in that: The antibacterial ceramic powder is prepared by the following steps: Add silicon carbide ceramic powder with a particle size of 30-40 μm, sodium citrate and ethylene glycol into a reactor, stir at 40-50°C and 500-600 r / min for 20-30 min, add sodium acetate into the reactor, heat to 80-90°C, continue stirring for 2-3 h, add nano zinc powder into the reactor, continue stirring for 2-3 h, and obtain antibacterial ceramic powder; The usage ratio of the silicon carbide ceramic powder, sodium citrate, ethylene glycol, sodium acetate and nano zinc powder is 10-12g: 2-3g: 200-300mL: 12-14g: 20-25g.

9. The method for producing a glass baking tray with non-stick function according to claim 1, characterized in that: The modified curing agent is prepared by the following steps: Add polyetheramine and deionized water into a reaction kettle, stir at 40-50°C and 400-500 r / min for 10-12 min, stir 4-hydroxybutyl vinyl ether, biphenyl dicarboxylic acid and deionized water at 70-80°C and 400-500 r / min for 1-2 h, add ferric sulfate into the reaction kettle, continue stirring and reacting for 5-6 h, add it dropwise into the reaction kettle at a speed of 40-45 drops / min, continue stirring and reacting for 3-4 h, filter, wash the filter cake with deionized water and anhydrous ethanol for 2-3 times respectively, and vacuum dry to obtain a modified curing agent; The usage ratio of the polyetheramine, deionized water, 4-hydroxybutyl vinyl ether, biphenyl dicarboxylic acid, deionized water and ferric sulfate is 10-12kg: 5-6L: 8-10kg: 10-11kg: 2-3L: 15-20g.

10. A glass baking tray with non-stick function, characterized in that: It is prepared by the production method according to any one of claims 1 to 9.

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