Nanometer material for heat accumulator of hot blast stove and preparation method of nanometer material

Abstract

The invention discloses a nano material for a heat accumulator of a hot blast stove and a preparation method of the nano material, and relates to the technical field of coating materials of hot blast stoves. The prepared nano material for the hot blast stove heat accumulator comprises a nano base material, borosilicate phenolic resin and an adhesive aluminum-silicon sol, and the borosilicate phenolic resin is prepared by adding a composite film-forming agent into a reaction of polyborosiloxane and phenolic resin. The composite film-forming agent is prepared by carrying out ternary polymerization on long-chain alkyl ester modified silane, triepoxypropyl isocyanurate and vinyl phenylboronic acid, and the long-chain alkyl ester modified silane is prepared by reacting hexadecyl acrylate, a silane oligomer and a silane coupling agent, so that the compression strength of the material is enhanced; the adhesive aluminum-silicon sol is prepared by adding acrylic polysiloxane into aluminum-silicon sol for reaction, and acrylic polysiloxane is prepared by copolymerizing hydroxyethyl acrylate and maleic anhydride and then reacting with amino modified polysiloxane, so that the thermal shock property is ensured, and the performance stability can be kept.

Description

Technical Field

[0001] The invention relates to the technical field of hot blast stove coating materials, in particular to a nano material for a hot blast stove heat storage body and a preparation method thereof. Background Art

[0002] Hot blast furnaces are an essential component of steel mill blast furnaces, providing high-temperature hot air exceeding 1000°C for smelting. Regenerative hot blast furnaces are the mainstream type of hot blast furnace in modern times, offering high thermal efficiency, large air volume, high temperature stability, and high heat exchange temperatures. During operation, they burn fuel to heat the regenerator within the regenerator chamber, which then heats the incoming cold air, ensuring continuous high-temperature hot air for the blast furnace.

[0003] Coating the surface of a heat accumulator with nanomaterials is an effective method for improving its surface properties and is currently being applied in industrial production. Currently, existing hot blast furnace coating materials mostly focus on nanoparticles that improve the radiation and heat storage capacity of the heat accumulator material. However, these materials do not consider further enhancing the heat accumulator's crack resistance, thus failing to meet the requirements for long-life and long-term stable production of hot blast furnaces. Therefore, the present invention has developed a nanomaterial for hot blast furnace heat accumulators that not only exhibits high thermal shock resistance but also improves the coating's crack resistance during thermal shock cycles. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a nano material for a hot blast stove heat storage body and a preparation method thereof.

[0005] The present invention proposes a technical solution to solve the above technical problems: a nano material for hot air furnace heat storage body, including a nano base material, borosilicate phenolic resin, an adhesive aluminum silica sol and a curing agent; the borosilicate phenolic resin is prepared by adding a composite film-forming agent to the reaction of polyborosiloxane and phenolic resin.

[0006] Preferably, the composite film-forming agent is prepared by ternary copolymerization of long-chain alkyl ester modified silane, triglycidyl isocyanurate and vinylphenylboric acid; the long-chain alkyl ester modified silane is prepared by the reaction of hexadecyl acrylate, silane oligomer and silane coupling agent; the silane coupling agent is KH-540 or KH-550.

[0007] Preferably, the adhesive aluminum silica sol is prepared by adding acrylic polysiloxane to aluminum silica sol for reaction; the acrylic polysiloxane is prepared by copolymerizing hydroxyethyl acrylate and maleic anhydride, and then reacting with amino-modified polysiloxane.

[0008] Preferably, the nano-based material comprises 10 to 20 parts by mass of brown corundum, 50 to 100 parts of bentonite, 40 to 80 parts of chromium oxide, 20 to 40 parts of titanium oxide, 10 to 20 parts of silicon carbide, 10 to 20 parts of silicon micropowder, 15 to 20 parts of nickel oxide and 60 to 80 parts of aluminum oxide; the particle size of each component of the nano-based material is 180 to 250; and the curing agent is magnesium oxide.

[0009] Preferably, the method for preparing the nanomaterial for the hot blast stove heat storage body comprises the following specific steps:

[0010] S1. Under a nitrogen atmosphere, hexadecyl acrylate, silane oligomer, silane coupling agent, and toluene are mixed in a mass ratio of 100:3-8:2-5:20-40, the temperature is raised to 65-68°C, 0.02-0.04 times the mass of azobisisobutyronitrile by weight of the hexadecyl acrylate is added, the pH is adjusted to 4-5 with acetic acid, the reaction is allowed to proceed for 2-3 hours, and then 0.02-0.04 times the mass of azobisisobutyronitrile by weight of the hexadecyl acrylate is added. The reaction is continued for 2-3 hours, the reaction is cooled to room temperature, the reaction is terminated with hydroquinone, and the mixture is distilled under reduced pressure to produce a long-chain alkyl ester-modified silane;

[0011] S2. Under a nitrogen atmosphere, long-chain alkyl ester-modified silane, isopropanol and toluene are mixed in a mass ratio of 5 to 7:1:1 to 2, the temperature is raised to 60 to 70°C, 0.4 to 0.5 times the mass of triepoxypropyl isocyanurate of the long-chain alkyl ester-modified silane is added, and 0.01 to 0.02 times the mass of p-toluenesulfonic acid of the long-chain alkyl ester-modified silane is added dropwise at a rate of 1 to 3 ml / min. After reacting for 1.5 to 2.5 hours, 0.2 to 0.3 times the mass of vinylbenzeneboric acid of the long-chain alkyl ester-modified silane is added, the reaction is continued for 3 to 4 hours, and after cooling to room temperature, the mixture is washed with a saturated sodium bicarbonate solution 3 to 5 times and distilled under reduced pressure to obtain a composite film-forming agent;

[0012] S3. Phenol, formaldehyde and sodium hydroxide were mixed in a mass ratio of 50:13~14:0.02~0.04, heated to 60~80 ° C, reacted for 1~2h, 0.4~0.6 times the mass of phenol and 0.08~0.12 times the mass of phenol composite film-forming agent were added, the reaction was continued for 1~2h, the pH was adjusted to 6.5~7.5 with sodium hydroxide, and dehydrated under reduced pressure to obtain borosilicate phenolic resin;

[0013] S4. Under a nitrogen atmosphere, maleic anhydride and toluene were mixed in a mass ratio of 1:4 to 5, heated to 90 to 110 ° C and stirred uniformly, and a mixture of hydroxyethyl acrylate and benzoyl peroxide (1.1 to 1.3 times the mass of maleic anhydride) was added dropwise at a rate of 1 to 3 ml / min. The mass ratio of hydroxyethyl acrylate to benzoyl peroxide in the mixture was 58:1 to 2, and the reaction was continued for 1 to 2 hours. The reaction was continued while hot and filtered and precipitated with methanol, and then washed with acetone 3 to 5 times, transferred to tetrahydrofuran (2 to 4 times the mass of maleic anhydride), and then 0.4 to 0.6 times the mass of maleic anhydride was added. Amino-modified polysiloxane was heated to 60 to 80 ° C, reacted for 4 to 6 hours, precipitated with ether and filtered, and dried in vacuo to obtain acrylic polysiloxane;

[0014] S5. Aluminum silica sol, γ-methacryloyloxysilane, and ethanol were mixed in a mass ratio of 40:1:10-20, reacted at room temperature for 8-10 hours, heated to 80-90°C, and added with 0.14-0.16 times the mass of the aluminum silica sol of acrylic polysiloxane and 0.01-0.02 times the mass of the aluminum silica sol of tetramethylammonium hydroxide as a catalyst. The mixture was allowed to react for 8-10 hours, heated to 180-220°C, and vacuum treated for 1-3 hours to obtain an aluminum silica sol binder.

[0015] S6. Mix the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent, stir evenly, and prepare the nano-material for hot air stove heat storage body.

[0016] Preferably, in the above step S1, the preparation method of the silane oligomer is: under a nitrogen atmosphere, octyltrimethoxysilane and methanol are mixed in a mass ratio of 50:2-3, and an acetic acid solution with a mass ratio of 0.11-0.13 times the mass of octyltrimethoxysilane is added dropwise at a rate of 1-3 ml / min, wherein the mass ratio of acetic acid, methanol and deionized water in the acetic acid solution is 1:1:10-20, and the pH is adjusted to 2-3 with acetic acid, and the reaction is carried out for 1-2 hours. The pH is adjusted to 7-8 with triethylamine, the temperature is raised to 78-82°C, the reaction is refluxed for 3-4 hours, the reaction is transferred to a vacuum environment by rotary evaporation, the oil bath is heated to 140-150°C, the temperature is kept for 3-4 hours, the reaction is cooled and filtered to obtain the silane oligomer.

[0017] Preferably, in the above step S3, the preparation method of polyborosiloxane is as follows: under a nitrogen atmosphere, dimethyldichlorosilane and tetrahydrofuran are mixed in a mass ratio of 1:2 to 2.2, placed in an ice bath, and a boric acid solution with a mass fraction of 40% to 50% of 0.15 to 0.25 times the mass of dimethyldichlorosilane is added dropwise at a rate of 1 to 3 ml / min, the temperature is raised to 80 to 90 ° C, and triethylamine with a mass of 0.05 to 0.08 times the mass of dimethyldichlorosilane is added, the reaction is carried out for 6 to 8 hours, and the mixture is filtered and distilled under reduced pressure to obtain polyborosiloxane.

[0018] Preferably, in the above step S4, the preparation method of amino-modified polysiloxane is as follows: under a nitrogen atmosphere, heating the hydrogenated silicone oil to 45-55°C, adding 0.02-0.04 times the mass of the hydrogenated silicone oil Karstedt catalyst, continuing to heat to 70-80°C, adding 1.02-1.08 times the mass of the hydrogenated silicone oil allyl glycidyl ether at a rate of 1-3 ml / min, reacting for 3-4 hours, adding 0.2-0.3 times the mass of the hydrogenated silicone oil diethylenetriamine and 0.6-0.8 times the mass of the hydrogenated silicone oil isopropanol, continuing the reaction for 2-3 hours, and distilling under reduced pressure to obtain amino-modified polysiloxane.

[0019] Preferably, in the above step S5, the preparation method of aluminum silica sol is: aluminum nitrate, citric acid and deionized water are mixed in a mass ratio of 3 to 3.4:1:1, stirred at room temperature at 400 to 800 rpm for 3 to 5 hours, heated to 98 to 102°C, kept warm for 40 to 60 minutes, and silica sol with a mass of 0.5 to 0.7 times that of aluminum nitrate is added. The silica sol is obtained by hydrolyzing ethyl orthosilicate at 60°C for 90 minutes, and then adding methyltriethoxysilane for aging for 5 to 6 hours. The molar ratio of ethyl orthosilicate to methyltriethoxysilane is 1:1. The reaction is continued for 1 to 2 hours to obtain aluminum silica sol.

[0020] Preferably, in the above step S6, the mass ratio of the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent is 4:0.6-0.8:10-12:1.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The nano material for hot blast stove heat storage prepared by the present invention comprises a nano base material, borosilicate phenolic resin and an adhesive aluminum silicate sol. The borosilicate phenolic resin is prepared by adding a composite film-forming agent to the reaction of polyborosiloxane and phenolic resin.

[0023] The composite film-forming agent is prepared by the ternary copolymerization of long-chain alkyl ester-modified silane, triglycidyl isocyanurate and vinyl phenyl boric acid. The long-chain alkyl ester-modified silane is prepared by the reaction of hexadecyl acrylate, silane oligomer and silane coupling agent. The introduction of alkyl ester into phenolic resin reduces the brittleness of the resin, and can also form a more stable carbon layer structure at high temperature, increase the residual carbon rate, and at the same time improve the coating's anti-cracking performance in thermal shock cycles, reduce microcracks caused by sudden temperature changes, and the introduced vinyl phenyl boric acid also confers a certain self-repairing ability to repair the tiny cracks caused by the composite film-forming agent and the borosilicate phenolic resin to form a cross-linked network in the material, thereby enhancing the material's compressive strength.

[0024] The adhesive aluminum silica sol is prepared by adding acrylic polysiloxane to the aluminum silica sol for reaction. The acrylic polysiloxane is prepared by copolymerizing hydroxyethyl acrylate and maleic anhydride and then reacting with amino-modified polysiloxane. The acrylic polysiloxane formed by the copolymerization of hydroxyethyl acrylate and maleic anhydride and the reaction with amino-modified polysiloxane can form a tighter and more stable cross-linked structure with the aluminum silica sol, so that the adhesive aluminum silica sol can be added to the nanomaterial to ensure thermal shock resistance. At the same time, the combination of borosilicate phenolic resin and the adhesive aluminum silica sol can also maintain performance stability.

[0025] The nanomaterial for the heat storage body of the hot blast furnace prepared by the present invention can reduce the time of baking the furnace and stopping the furnace from more than 23 days to 12 days, and improves the heat storage and heat exchange capacity, with very significant energy-saving and consumption-reducing effects. DETAILED DESCRIPTION

[0026] The present invention is described in detail below through examples. It should be noted that the following examples are intended only to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Those skilled in the art may make non-essential improvements and adjustments to the present invention based on the above disclosure. Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art.

[0027] When preparing the nanomaterial on the surface of the hot air stove regenerator, dust and particulate matter on the surface and in the pores are removed in advance, and then the sample is dipped in a pretreatment solution composed of water glass, xanthan gum, sodium tetraborate, and water. The sample is then dipped in the evenly stirred materials of the embodiment and the comparative example for 5 seconds, taken out and dried in an oven at 110°C, and then cured at 1200°C for 2 hours to form a nanomaterial with a thickness of 300 μm on the surface of the hot air stove regenerator for testing.

[0028] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of the nanomaterials for hot blast stove heat storage bodies prepared in the examples and comparative examples as follows:

[0029] Emissivity: The emissivity of the hot air furnace heat storage body is tested using nanomaterials using a radiation rate tester.

[0030] Thermal expansion coefficient: The thermal expansion coefficient of the hot air stove heat storage body is tested with nano materials according to GB / T 16535.

[0031] Thermal shock resistance: The hot air furnace heat storage body is made of nanomaterials and subjected to a 1300℃ rapid cooling and heating cycle test in accordance with GB / T 31934.

[0032] Compressive strength: The hot air furnace heat storage body is tested for compressive strength using nanomaterials in accordance with GB / T 2997.

[0033] Anti-cracking performance: Observe the surface cracks of the nanomaterial used in the hot air furnace heat storage body after the thermal shock test.

[0034] Example 1

[0035] The weight proportions of the components in the nanomaterial for the hot blast stove heat storage body in this embodiment are: 4 parts of nano-base material, 0.6 parts of borosilicate phenolic resin, 10 parts of adhesive aluminum silicate sol and 1 part of curing agent; the nano-base material includes 10 parts of brown corundum, 50 parts of bentonite, 40 parts of chromium oxide, 20 parts of titanium oxide, 10 parts of silicon carbide, 10 parts of silicon powder, 15 parts of nickel oxide and 60 parts of aluminum oxide.

[0036] The preparation method of the nanomaterial for the heat storage body of the hot blast stove in this embodiment is as follows:

[0037] S1. Under a nitrogen atmosphere, octyltrimethoxysilane and methanol were mixed in a mass ratio of 50:2, and an acetic acid solution (0.11 times the mass of octyltrimethoxysilane) was added dropwise at a rate of 1 ml / min. The mass ratio of acetic acid, methanol, and deionized water in the acetic acid solution was 1:1:10. The pH was adjusted to 2 with acetic acid, and the reaction was carried out for 1-2 hours. The pH was adjusted to 7 with triethylamine, and the temperature was raised to 78°C. The reaction was refluxed for 3 hours, and the mixture was transferred to a vacuum environment by rotary evaporation. The oil bath temperature was raised to 140°C, and the temperature was kept for 3 hours. The mixture was cooled and filtered to obtain silane. oligomer; under a nitrogen atmosphere, hexadecyl acrylate, silane oligomer, silane coupling agent and toluene are mixed in a mass ratio of 100:3:2:20, the temperature is raised to 65° C., 0.02 times the mass of azobisisobutyronitrile by weight of hexadecyl acrylate is added, the pH is adjusted to 4 with acetic acid, and the reaction is carried out for 2 hours. Then, 0.02 to 0.04 times the mass of azobisisobutyronitrile by weight of hexadecyl acrylate is added, the reaction is continued for 2 hours, and the reaction is cooled to room temperature. The reaction is terminated with hydroquinone and distilled under reduced pressure to obtain a long-chain alkyl ester modified silane;

[0038] S2. Under a nitrogen atmosphere, long-chain alkyl ester-modified silane, isopropyl alcohol, and toluene were mixed in a mass ratio of 5:1:1, heated to 60°C, and 0.4 times the mass of triepoxypropyl isocyanurate relative to the mass of the long-chain alkyl ester-modified silane was added. 0.01 times the mass of p-toluenesulfonic acid relative to the mass of the long-chain alkyl ester-modified silane was added dropwise at a rate of 1 ml / min. After reacting for 1.5 h, 0.2 times the mass of vinylphenylboronic acid relative to the mass of the long-chain alkyl ester-modified silane was added. The reaction was continued for 3 h. After cooling to room temperature, the mixture was washed three times with a saturated sodium bicarbonate solution and distilled under reduced pressure to obtain a composite film-forming agent.

[0039] S3. Under a nitrogen atmosphere, dimethyldichlorosilane and tetrahydrofuran were mixed in a mass ratio of 1:2, placed in an ice bath, and a 40% boric acid solution of 0.15 times the mass of dimethyldichlorosilane was added dropwise at a rate of 1 ml / min, the temperature was raised to 80°C, and triethylamine of 0.05 times the mass of dimethyldichlorosilane was added. The reaction was carried out for 6 hours, filtered and distilled under reduced pressure to obtain polyborosiloxane; phenol, formaldehyde and sodium hydroxide were mixed in a mass ratio of 50:13:0.02, heated to 60°C, reacted for 1 hour, and polyborosiloxane of 0.4 times the mass of phenol and a composite film-forming agent of 0.08 times the mass of phenol were added. The reaction was continued for 1 hour, the pH was adjusted to 6.5 with sodium hydroxide, and dehydrated under reduced pressure to obtain borosilicate phenolic resin;

[0040] S4. Under a nitrogen atmosphere, the hydrogenated silicone oil was heated to 45°C, Karstedt catalyst (0.02 times the mass of the hydrogenated silicone oil) was added, the temperature was continued to rise to 70°C, allyl glycidyl ether (1.02 times the mass of the hydrogenated silicone oil) was added dropwise at a rate of 1 ml / min, the reaction was continued for 3 h, diethylenetriamine (0.2 times the mass of the hydrogenated silicone oil) and isopropanol (0.6 times the mass of the hydrogenated silicone oil) were added, the reaction was continued for 2 h, and the amino-modified polysiloxane was obtained by vacuum distillation. Under a nitrogen atmosphere, maleic anhydride and toluene were mixed in a mass ratio of 1:4, the temperature was continued to rise to 9 After stirring evenly at 0°C, a mixture of hydroxyethyl acrylate and benzoyl peroxide (1.1 times the mass of maleic anhydride) was added dropwise at a rate of 1 ml / min, wherein the mass ratio of hydroxyethyl acrylate to benzoyl peroxide in the mixture was 58:1, and the reaction was continued for 1 hour. The mixture was filtered while hot and precipitated with methanol, then washed with acetone 3 times, transferred to tetrahydrofuran (2 times the mass of maleic anhydride), and then amino-modified polysiloxane (0.4 times the mass of maleic anhydride) was added. The temperature was raised to 60°C, the reaction was carried out for 4 hours, precipitated with ether, filtered, and dried in vacuo to obtain acrylic polysiloxane.

[0041] S5. Aluminum nitrate, citric acid and deionized water were mixed in a mass ratio of 3:1:1, stirred at room temperature for 3 hours at 400 rpm, heated to 98 ° C, kept warm for 40 minutes, and 0.5 times the mass of aluminum nitrate was added. The silica sol was ethyl orthosilicate hydrolyzed at 60 ° C for 90 minutes, and then methyltriethoxysilane was added for 5 hours. The molar ratio of ethyl orthosilicate to methyltriethoxysilane was 1:1. The reaction was continued for 1 hour to obtain aluminum silica sol; aluminum silica sol, γ-methacryloyloxysilane and ethanol were mixed in a mass ratio of 40:1:10, reacted at room temperature for 8 hours, heated to 80 ° C, and 0.14 times the mass of aluminum silica sol and 0.01 times the mass of aluminum silica sol. Tetramethylammonium hydroxide was added as a catalyst, reacted for 8 hours, heated to 180 ° C, and vacuum treated for 1 hour to obtain a binder aluminum silica sol;

[0042] S6. Mix the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent, stir evenly, and prepare the nano-material for hot air stove heat storage body.

[0043] Example 2

[0044] In this embodiment, the weight proportions of the components in the nanomaterial for the hot blast furnace heat storage body are: 4 parts of nano-base material, 0.7 parts of borosilicate phenolic resin, 11 parts of adhesive aluminum silicate sol and 1 part of curing agent; the nano-base material includes 15 parts of brown corundum, 80 parts of bentonite, 60 parts of chromium oxide, 30 parts of titanium oxide, 15 parts of silicon carbide, 15 parts of silicon powder, 17 parts of nickel oxide and 70 parts of aluminum oxide.

[0045] The preparation method of the nanomaterial for the heat storage body of the hot blast stove in this embodiment is as follows:

[0046] S1. Under a nitrogen atmosphere, octyltrimethoxysilane and methanol were mixed in a mass ratio of 50:2.5, and an acetic acid solution (0.12 times the mass of octyltrimethoxysilane) was added dropwise at a rate of 2 ml / min. The mass ratio of acetic acid, methanol, and deionized water in the acetic acid solution was 1:1:15. The pH was adjusted to 2.5 with acetic acid, and the reaction was continued for 1.5 h. The pH was adjusted to 7.5 with triethylamine, and the temperature was raised to 80°C. The reaction was refluxed for 3.5 h, and the mixture was transferred to a vacuum environment by rotary evaporation. The oil bath temperature was raised to 145°C, and the temperature was kept at this temperature for 3.5 h. The mixture was cooled and filtered. preparing a silane oligomer; under a nitrogen atmosphere, mixing hexadecyl acrylate, a silane oligomer, a silane coupling agent, and toluene in a mass ratio of 100:6:3.5:30, heating to 66° C., adding 0.03 times the mass of azobisisobutyronitrile by weight of the hexadecyl acrylate, adjusting the pH to 4.5 with acetic acid, reacting for 2.5 hours, then adding 0.03 times the mass of azobisisobutyronitrile by weight of the hexadecyl acrylate, continuing the reaction for 2.5 hours, cooling to room temperature, terminating the reaction with hydroquinone, and distilling under reduced pressure to prepare a long-chain alkyl ester-modified silane;

[0047] S2. Under a nitrogen atmosphere, long-chain alkyl ester-modified silane, isopropyl alcohol, and toluene were mixed in a mass ratio of 6:1:1.5, heated to 65°C, and 0.45 times the mass of triepoxypropyl isocyanurate of the long-chain alkyl ester-modified silane was added. 0.015 times the mass of p-toluenesulfonic acid of the long-chain alkyl ester-modified silane was added dropwise at a rate of 2 ml / min. After reacting for 2 h, 0.25 times the mass of vinylbenzeneboric acid of the long-chain alkyl ester-modified silane was added. The reaction was continued for 3.5 h. After cooling to room temperature, the mixture was washed four times with a saturated sodium bicarbonate solution and distilled under reduced pressure to obtain a composite film-forming agent.

[0048] S3. Under a nitrogen atmosphere, dimethyldichlorosilane and tetrahydrofuran were mixed in a mass ratio of 1:2.1, placed in an ice bath, and a 45% boric acid solution of 0.2 times the mass of dimethyldichlorosilane was added dropwise at a rate of 2 ml / min, the temperature was raised to 85°C, and triethylamine was added in an amount of 0.06 times the mass of dimethyldichlorosilane. The mixture was reacted for 7 hours, filtered and distilled under reduced pressure to obtain polyborosiloxane; phenol, formaldehyde and sodium hydroxide were mixed in a mass ratio of 50:13.5:0.03, heated to 70°C, reacted for 1.5 hours, polyborosiloxane of 0.5 times the mass of phenol and a composite film-forming agent of 0.1 times the mass of phenol were added, the reaction was continued for 1.5 hours, the pH was adjusted to 7.0 with sodium hydroxide, and dehydrated under reduced pressure to obtain borosilicate phenolic resin;

[0049] S4. Under a nitrogen atmosphere, the hydrogenated silicone oil was heated to 50°C, 0.03 times the mass of the hydrogenated silicone oil was added with Karstedt catalyst, the temperature was continued to be raised to 75°C, 1.02 to 1.08 times the mass of the hydrogenated silicone oil was added dropwise at a rate of 2 ml / min, the reaction was continued for 3.5 hours, 0.25 times the mass of the hydrogenated silicone oil was added with diethylenetriamine and 0.7 times the mass of the hydrogenated silicone oil was added with isopropanol, the reaction was continued for 2.5 hours, and the amino-modified polysiloxane was obtained by distillation under reduced pressure; under a nitrogen atmosphere, maleic anhydride and toluene were mixed in a mass ratio of 1:4.5, and the mixture was heated to 40°C. After warming to 100°C and stirring evenly, a mixture of hydroxyethyl acrylate and benzoyl peroxide (1.2 times the mass of maleic anhydride) was added dropwise at a rate of 2 ml / min, wherein the mass ratio of hydroxyethyl acrylate to benzoyl peroxide in the mixture was 58:1.5, and the reaction was continued for 1.5 hours. The mixture was filtered while hot and precipitated with methanol, then washed with acetone 4 times, transferred to tetrahydrofuran (3 times the mass of maleic anhydride), and then amino-modified polysiloxane (0.5 times the mass of maleic anhydride) was added. The mixture was heated to 70°C and reacted for 5 hours. The mixture was precipitated with ether and filtered, and vacuum dried to obtain acrylic polysiloxane.

[0050] S5. Aluminum nitrate, citric acid and deionized water were mixed in a mass ratio of 3.2:1:1, stirred at room temperature for 4 hours at 600 rpm, heated to 100 ° C, kept warm for 50 minutes, and 0.6 times the mass of aluminum nitrate was added. The silica sol was ethyl orthosilicate hydrolyzed at 60 ° C for 90 minutes, and then methyltriethoxysilane was added for 5.5 hours. The molar ratio of ethyl orthosilicate to methyltriethoxysilane was 1:1. The reaction was continued for 1.5 hours to obtain aluminum silica sol; aluminum silica sol, γ-methacryloyloxysilane and ethanol were mixed in a mass ratio of 40:1:15, reacted at room temperature for 9 hours, heated to 85 ° C, and 0.15 times the mass of aluminum silica sol and 0.015 times the mass of aluminum silica sol. Tetramethylammonium hydroxide catalyst was added, reacted for 9 hours, heated to 200 ° C, and vacuum treated for 2 hours to obtain a binder aluminum silica sol;

[0051] S6. Mix the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent, stir evenly, and prepare the nano-material for hot air stove heat storage body.

[0052] Example 3

[0053] The preparation method of the nanomaterial for the heat storage body of the hot blast stove in this embodiment is as follows:

[0054] The weight proportions of the components in the nanomaterial for the heat storage body of the hot blast furnace in this embodiment are: 4 parts of nano-base material, 0.8 parts of borosilicate phenolic resin, 12 parts of adhesive aluminum silicate sol and 1 part of curing agent; the nano-base material includes 20 parts of brown corundum, 100 parts of bentonite, 80 parts of chromium oxide, 40 parts of titanium oxide, 20 parts of silicon carbide, 20 parts of silicon powder, 20 parts of nickel oxide and 80 parts of aluminum oxide.

[0055] The preparation method of the nanomaterial for the heat storage body of the hot blast stove in this embodiment is as follows:

[0056] S1. Under a nitrogen atmosphere, octyltrimethoxysilane and methanol were mixed in a mass ratio of 50:3, and an acetic acid solution with a mass ratio of 0.13 times the mass of octyltrimethoxysilane was added dropwise at a rate of 3 ml / min. The mass ratio of acetic acid, methanol and deionized water in the acetic acid solution was 1:1:20. The pH was adjusted to 3 with acetic acid, and the reaction was continued for 2 h. The pH was adjusted to 8 with triethylamine, and the temperature was raised to 82°C. The reaction was refluxed for 4 h, and the mixture was transferred to a vacuum environment by rotary evaporation. The oil bath temperature was raised to 150°C, and the mixture was kept warm for 4 h. The mixture was cooled and filtered to obtain the product. Silane oligomer; under a nitrogen atmosphere, hexadecyl acrylate, silane oligomer, silane coupling agent and toluene are mixed in a mass ratio of 100:8:5:40, the temperature is raised to 68°C, 0.04 times the mass of azobisisobutyronitrile by weight of hexadecyl acrylate is added, the pH is adjusted to 5 with acetic acid, and the reaction is carried out for 3 hours. Then, 0.04 times the mass of azobisisobutyronitrile by weight of hexadecyl acrylate is added, the reaction is continued for 3 hours, and the reaction is cooled to room temperature. The reaction is terminated with hydroquinone and distilled under reduced pressure to obtain a long-chain alkyl ester modified silane;

[0057] S2. Under a nitrogen atmosphere, long-chain alkyl ester-modified silane, isopropanol, and toluene were mixed in a mass ratio of 7:1:2, heated to 70°C, and triepoxypropyl isocyanurate (0.5 times the mass of the long-chain alkyl ester-modified silane) was added. P-toluenesulfonic acid (0.02 times the mass of the long-chain alkyl ester-modified silane) was added dropwise at a rate of 3 ml / min. After reacting for 2.5 h, vinylbenzeneboric acid (0.3 times the mass of the long-chain alkyl ester-modified silane) was added. The reaction was continued for 4 h, cooled to room temperature, washed five times with a saturated sodium bicarbonate solution, and distilled under reduced pressure to obtain a composite film-forming agent.

[0058] S3. Under a nitrogen atmosphere, dimethyldichlorosilane and tetrahydrofuran were mixed in a mass ratio of 1:2.2, placed in an ice bath, and a 50% boric acid solution of 0.25 times the mass of dimethyldichlorosilane was added dropwise at a rate of 3 ml / min, the temperature was raised to 90°C, and triethylamine of 0.08 times the mass of dimethyldichlorosilane was added. The reaction was carried out for 8 hours, filtered and distilled under reduced pressure to obtain polyborosiloxane; phenol, formaldehyde and sodium hydroxide were mixed in a mass ratio of 50:14:0.04, heated to 80°C, reacted for 2 hours, and polyborosiloxane of 0.6 times the mass of phenol and a composite film-forming agent of 0.12 times the mass of phenol were added. The reaction was continued for 2 hours, the pH was adjusted to 7.5 with sodium hydroxide, and dehydrated under reduced pressure to obtain borosilicate phenolic resin;

[0059] S4. Under a nitrogen atmosphere, the hydrogenated silicone oil was heated to 45°C, Karstedt catalyst (0.02 times the mass of the hydrogenated silicone oil) was added, the temperature was continued to rise to 70°C, allyl glycidyl ether (1.08 times the mass of the hydrogenated silicone oil) was added dropwise at a rate of 1 ml / min, the reaction was continued for 4 hours, diethylenetriamine (0.2 times the mass of the hydrogenated silicone oil) and isopropanol (0.8 times the mass of the hydrogenated silicone oil) were added, the reaction was continued for 2 hours, and the amino-modified polysiloxane was obtained by vacuum distillation. Under a nitrogen atmosphere, maleic anhydride and toluene were mixed in a mass ratio of 1:5, the temperature was raised to 11 After stirring evenly at 0°C, a mixture of hydroxyethyl acrylate and benzoyl peroxide (1.3 times the mass of maleic anhydride) was added dropwise at a rate of 1 ml / min, wherein the mass ratio of hydroxyethyl acrylate to benzoyl peroxide in the mixture was 58:2, and the reaction was continued for 2 hours. The mixture was filtered while hot and precipitated with methanol, then washed with acetone 5 times, transferred to tetrahydrofuran (4 times the mass of maleic anhydride), and then amino-modified polysiloxane (0.6 times the mass of maleic anhydride) was added. The temperature was raised to 80°C, the reaction was carried out for 6 hours, precipitated with ether, filtered, and dried in vacuo to obtain acrylic polysiloxane.

[0060] S5. Aluminum nitrate, citric acid and deionized water were mixed in a mass ratio of 3.4:1:1, stirred at room temperature at 800 rpm for 5 h, heated to 102 ° C, kept warm for 60 min, and 0.7 times the mass of aluminum nitrate was added. The silica sol was ethyl orthosilicate hydrolyzed at 60 ° C for 90 min, and then methyltriethoxysilane was added for 6 h. The molar ratio of ethyl orthosilicate to methyltriethoxysilane was 1:1. The reaction was continued for 2 h to obtain aluminum silica sol; aluminum silica sol, γ-methacryloyloxysilane and ethanol were mixed in a mass ratio of 40:1:20, reacted at room temperature for 10 h, heated to 90 ° C, 0.16 times the mass of aluminum silica sol and 0.02 times the mass of aluminum silica sol as a catalyst tetramethylammonium hydroxide were added, reacted for 10 h, heated to 220 ° C, and vacuum treated for 3 h to obtain an adhesive aluminum silica sol;

[0061] S6. Mix the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent, stir evenly, and prepare the nano-material for hot air stove heat storage body.

[0062] Comparative Example 1

[0063] The preparation method of Comparative Example 1 is the same as that of Example 2. The difference between the nanomaterial for hot air stove heat storage body and Example 2 is that the composite film-forming agent is prepared by ternary copolymerization of silane coupling agent, triglycidyl isocyanurate and vinylphenylboric acid.

[0064] Comparative Example 2

[0065] The preparation method of Comparative Example 2 is the same as that of Example 2. The difference between the nanomaterial for heating element prepared by the hot air furnace and Example 2 is that the composite film-forming agent is prepared by ternary copolymerization of silane oligomer, triglycidyl isocyanurate and vinylphenylboronic acid.

[0066] Comparative Example 3

[0067] The preparation method of Comparative Example 3 is the same as that of Example 2. The difference between the nanomaterial for hot blast stove heat storage body and Example 2 is that the borosilicate phenolic resin is simply the reaction of polyborosiloxane and phenolic resin.

[0068] Comparative Example 4

[0069] The preparation method of Comparative Example 4 is the same as that of Example 2. The difference between the nanomaterial for hot blast stove heat storage body and Example 2 is that the binder aluminum silica sol is prepared by adding amino-modified polysiloxane to the aluminum silica sol.

[0070] Comparative Example 5

[0071] The preparation method of Comparative Example 5 is the same as that of Example 2. The difference between the nanomaterial for hot blast stove heat storage body and Example 2 is that the binder aluminum silica sol is only aluminum silica sol.

[0072] Effect Examples

[0073] Table 1 below shows the performance test results of the nanomaterials for hot blast stove heat storage bodies prepared in Examples and Comparative Examples;

[0074] Table 1

[0075] Emissivity Thermal expansion coefficient (℃) Thermal shock resistance (times) Compressive strength (MPa) Cracking resistance Example 1 0.93 <![CDATA[8.3×10 -6 ]]> 69 85.4 No cracks Example 2 0.94 <![CDATA[8.5×10 -6 ]]> 77 87.6 No cracks Example 3 0.93 <![CDATA[8.3×10 -6 ]]> 71 85.9 No cracks Comparative Example 1 0.93 <![CDATA[8.0×10 -6 ]]> 68 70.2 Small cracks Comparative Example 2 0.92 <![CDATA[8.0×10 -6 ]]> 67 71.5 Small cracks Comparative Example 3 0.93 <![CDATA[7.3×10 -6 ]]> 66 66.4 Small cracks Comparative Example 4 0.91 <![CDATA[7.2×10 -6 ]]> 60 84.6 No cracks Comparative Example 5 0.90 <![CDATA[7.0×10 -6 ]]> 59 83.5 No cracks

[0076] From the comparison of the performance data in Table 1, it can be seen that the nanomaterial for hot blast stove heat storage prepared by the present invention not only has excellent emissivity, thermal expansion coefficient, thermal shock resistance and cracking resistance;

[0077] From the comparison of the experimental data of Example 1, Example 2, Example 3 and Comparative Example 1, Comparative Example 2, Comparative Example 3, it can be found that the introduction of alkyl esters into the phenolic resin reduces the brittleness of the resin, and can also form a more stable carbon layer structure at high temperature, increase the residual carbon rate, and at the same time improve the coating's resistance to cracking in thermal shock cycles, reduce microcracks caused by sudden temperature changes, and the introduced vinylbenzene boric acid also imparts a certain self-repairing ability, which can repair the tiny cracks caused by the cross-linking network formed by the composite film-forming agent and the borosilicate phenolic resin in the material, thereby enhancing the compressive strength of the material.

[0078] From the comparison of the experimental data of Examples 1, 2, and 3 and Comparative Examples 4 and 5, it can be found that the acrylic polysiloxane formed by the copolymerization of hydroxyethyl acrylate and maleic anhydride and the reaction with amino-modified polysiloxane can form a tighter and more stable cross-linked structure with the aluminum silica sol, so that the adhesive aluminum silica sol is added to the nanomaterial to ensure thermal shock resistance. At the same time, the combination of borosilicate phenolic resin and the adhesive aluminum silica sol can also maintain performance stability.

[0079] The nanomaterial for the heat storage body of the hot blast furnace prepared by the present invention can reduce the time of baking the furnace and stopping the furnace from more than 23 days to 12 days, and improves the heat storage and heat exchange capacity, with very significant energy-saving and consumption-reducing effects.

[0080] Obviously, the above embodiments are merely examples for the purpose of clearly illustrating the embodiments of the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will readily appreciate that other variations or modifications based on the above description are possible. It is not necessary and impossible to enumerate all embodiments here. However, such obvious variations or modifications arising from the spirit of the present invention remain within the scope of protection of the present invention.

Claims

1. A nanomaterial for hot blast stove heat storage body, characterized in that: The invention comprises a nanometer base material, borosilicate phenolic resin, an adhesive aluminum silica sol and a curing agent; the borosilicate phenolic resin is prepared by adding a composite film-forming agent into the reaction of polyborosiloxane and phenolic resin.

2. The nanomaterial for hot blast stove heat storage body according to claim 1, characterized in that: The composite film-forming agent is prepared by ternary copolymerization of long-chain alkyl ester modified silane, triglycidyl isocyanurate and vinylphenylboric acid; the long-chain alkyl ester modified silane is prepared by the reaction of hexadecyl acrylate, silane oligomer and silane coupling agent; the silane coupling agent is KH-540 or KH-550.

3. The nanomaterial for hot blast stove heat storage body according to claim 1, characterized in that: The adhesive aluminum silica sol is prepared by adding acrylic polysiloxane to aluminum silica sol for reaction; the acrylic polysiloxane is prepared by copolymerizing hydroxyethyl acrylate and maleic anhydride and then reacting with amino-modified polysiloxane.

4. The nanomaterial for hot blast stove heat storage body according to claim 1, characterized in that: The nano-based material comprises 10-20 parts by mass of brown corundum, 50-100 parts of bentonite, 40-80 parts of chromium oxide, 20-40 parts of titanium oxide, 10-20 parts of silicon carbide, 10-20 parts of silicon micropowder, 15-20 parts of nickel oxide and 60-80 parts of aluminum oxide; the particle size of each component of the nano-based material is 180-250; and the curing agent is magnesium oxide.

5. The method for preparing a nanomaterial for a hot blast stove heat storage body according to claim 1, characterized in that: The specific steps include: S1. Under a nitrogen atmosphere, hexadecyl acrylate, silane oligomer, silane coupling agent, and toluene were mixed in a mass ratio of 100:3-8:2-5:20-40, heated to 65-68°C, and azobisisobutyronitrile (0.02-0.04 times the mass of the hexadecyl acrylate) was added. The pH was adjusted to 4-5 with acetic acid. After reacting for 2-3 hours, azobisisobutyronitrile (0.02-0.04 times the mass of the hexadecyl acrylate) was added and the reaction was continued for 2-3 hours. The mixture was cooled to room temperature, terminated with hydroquinone, and subjected to reduced pressure distillation to produce a long-chain alkyl ester-modified silane. S2. Under a nitrogen atmosphere, long-chain alkyl ester-modified silane, isopropyl alcohol, and toluene were mixed in a mass ratio of 5-7:1:1-2, heated to 60-70°C, and triepoxypropyl isocyanurate (0.4-0.5 times the mass of the long-chain alkyl ester-modified silane) was added. P-toluenesulfonic acid (0.01-0.02 times the mass of the long-chain alkyl ester-modified silane) was added dropwise at a rate of 1-3 ml / min. After reacting for 1.5-2.5 h, vinylbenzeneboric acid (0.2-0.3 times the mass of the long-chain alkyl ester-modified silane) was added. The reaction was continued for 3-4 h. After cooling to room temperature, the mixture was washed with a saturated sodium bicarbonate solution 3-5 times and distilled under reduced pressure to obtain a composite film-forming agent. S3. Phenol, formaldehyde, and sodium hydroxide were mixed in a mass ratio of 50:13-14:0.02-0.04, heated to 60-80°C, and reacted for 1-2 hours. Polyborosiloxane (0.4-0.6 times the mass of phenol) and a composite film-forming agent (0.08-0.12 times the mass of phenol) were added, and the reaction was continued for 1-2 hours. The pH was adjusted to 6.5-7.5 with sodium hydroxide, and dehydrated under reduced pressure to produce a borosilicate phenolic resin. S4. Under a nitrogen atmosphere, maleic anhydride and toluene were mixed in a mass ratio of 1:4~5, heated to 90~110°C and stirred uniformly, and a mixture of hydroxyethyl acrylate and benzoyl peroxide (1.1~1.3 times the mass of maleic anhydride) was added dropwise at a rate of 1~3 ml / min, wherein the mass ratio of hydroxyethyl acrylate to benzoyl peroxide in the mixture was 58:1~2, and the reaction was continued for 1~2 hours. The mixture was filtered while hot and precipitated with methanol, then washed with acetone 3~5 times, transferred to tetrahydrofuran (2~4 times the mass of maleic anhydride), and then 0.4~0.6 times the mass of maleic anhydride was added with amino-modified polysiloxane, heated to 60~80°C, reacted for 4~6 hours, precipitated with ether and filtered, and dried in vacuo to obtain acrylic polysiloxane; S5. Alumina silica sol, γ-methacryloyloxysilane, and ethanol were mixed in a mass ratio of 40:1:10-20, reacted at room temperature for 8-10 hours, heated to 80-90°C, and added with 0.14-0.16 times the mass of the alumina silica sol in acrylic polysiloxane and 0.01-0.02 times the mass of the alumina silica sol in tetramethylammonium hydroxide as a catalyst. The mixture was allowed to react for 8-10 hours, heated to 180-220°C, and vacuum-treated for 1-3 hours to produce an alumina silica sol binder. S6. Mix the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent, stir evenly, and prepare the nano-material for hot air stove heat storage body.

6. The method for preparing a nanomaterial for a hot blast stove heat storage body according to claim 5, characterized in that: In the above step S1, the preparation method of the silane oligomer is as follows: under a nitrogen atmosphere, octyltrimethoxysilane and methanol are mixed in a mass ratio of 50:2~3, and an acetic acid solution with a mass ratio of 0.11~0.13 times the mass of octyltrimethoxysilane is added dropwise at a rate of 1~3 ml / min, wherein the mass ratio of acetic acid, methanol and deionized water in the acetic acid solution is 1:1:10~20, and the pH is adjusted to 2~3 with acetic acid, and the reaction is carried out for 1~2 hours. The pH is adjusted to 7~8 with triethylamine, the temperature is raised to 78~82°C, the reaction is refluxed for 3~4 hours, the reaction is transferred to a vacuum environment by rotary evaporation, the oil bath is heated to 140~150°C, the temperature is kept for 3~4 hours, the reaction is cooled and filtered to obtain a silane oligomer.

7. The method for preparing a nanomaterial for a hot blast stove heat storage body according to claim 5, characterized in that: In the above step S3, the preparation method of polyborosiloxane is as follows: under a nitrogen atmosphere, dimethyldichlorosilane and tetrahydrofuran are mixed in a mass ratio of 1:2~2.2, placed in an ice bath, and a boric acid solution with a mass fraction of 40~50% of 0.15~0.25 times the mass of dimethyldichlorosilane is added dropwise at a rate of 1~3 ml / min, and the temperature is raised to 80~90 ° C., 0.05~0.08 times the mass of dimethyldichlorosilane is added, triethylamine is added, and the reaction is carried out for 6~8 hours. Filter and distill under reduced pressure to obtain polyborosiloxane.

8. The method for preparing a nanomaterial for a hot blast stove heat storage body according to claim 5, characterized in that: In the above step S4, the preparation method of amino-modified polysiloxane is as follows: under a nitrogen atmosphere, heating the hydrogenated silicone oil to 45-55°C, adding 0.02-0.04 times the mass of the hydrogenated silicone oil in the amount of Karstedt catalyst, continuing to heat to 70-80°C, adding 1.02-1.08 times the mass of the hydrogenated silicone oil in the amount of allyl glycidyl ether at a rate of 1-3 ml / min, reacting for 3-4 hours, adding 0.2-0.3 times the mass of the hydrogenated silicone oil in the amount of diethylenetriamine and 0.6-0.8 times the mass of the hydrogenated silicone oil in the amount of isopropanol, continuing the reaction for 2-3 hours, and distilling under reduced pressure to obtain amino-modified polysiloxane.

9. The method for preparing a nanomaterial for a hot blast stove heat storage body according to claim 5, characterized in that: In the above step S5, the preparation method of aluminum silica sol is as follows: aluminum nitrate, citric acid and deionized water are mixed in a mass ratio of 3-3.4:1:1, stirred at room temperature at 400-800 rpm for 3-5 hours, heated to 98-102°C, kept warm for 40-60 minutes, and silica sol with a mass of 0.5-0.7 times that of aluminum nitrate is added. The silica sol is obtained by hydrolyzing ethyl orthosilicate at 60°C for 90 minutes, then adding methyltriethoxysilane and aging for 5-6 hours. The molar ratio of ethyl orthosilicate to methyltriethoxysilane is 1:

1. The reaction is continued for 1-2 hours to obtain aluminum silica sol.

10. The method for preparing nanomaterials for hot blast stove heat storage body according to claim 5, characterized in that: In the above step S6, the mass ratio of the nano-base material, borosilicate phenolic resin, adhesive aluminum silica sol and curing agent is 4:0.6~0.8:10~12:1.