A kind of thermal insulation floor for building and preparation method thereof

Abstract

The present invention relates to a thermal insulation floor for building and a preparation method thereof, and belongs to the technical field of composite floor. The thermal insulation floor is composed of a substrate and a thermal insulation coating on the surface, and the thermal insulation coating is formed by curing the thermal insulation coating, and includes by weight: 100 parts of acrylic emulsion, 16-22 parts of microporous composite filler, 0.2-0.3 parts of wetting dispersant, 0.1-0.15 parts of leveling agent, 0.3-0.4 parts of anti-settling agent and 15-20 parts of diluent; the microporous composite filler uses graphene oxide as a carrier, forms a porous silicon-magnesium-aluminum composite layer on the surface, and is dispersed in the thermal insulation coating to form countless line-surface and surface-surface shielding protection structures, greatly reducing the thermal conductivity of the coating, improving the thermal insulation performance of the floor, and the graphene sheet layer of the core layer has excellent anti-permeability, giving the thermal insulation barrier good water resistance, effectively reducing the water absorption of the thermal insulation coating of the acrylic matrix, effectively preventing the floor from being damp and rotten, and helping to improve the service life of the floor.

Description

Technical Field

[0001] The invention belongs to the technical field of composite floors, and in particular, relates to a thermal insulation floor for buildings and a preparation method thereof. Background Art

[0002] As people's demand for a more comfortable living environment continues to increase, heating and cooling equipment are generally installed indoors. The heat / cold generated by these devices is exchanged through walls and the ground, causing the equipment to work continuously to ensure a comfortable indoor environment, which in turn causes energy loss.

[0003] In view of the heat exchange problem of indoor floors, the traditional technical solution is to lay insulation materials, such as insulation mortar, insulation cotton, etc., on the floor before installing the floor, which makes the construction of the floor complicated; in the prior art, an insulation layer is set in a traditional board through board composite technology, which can effectively improve the insulation performance of the floor, but the production process of this board is complicated, and in the composite process, a large amount of adhesives are used to ensure the composite strength, resulting in insufficient environmental protection; the coated insulation floor is a new type of board, which is provided with a good insulation performance while encapsulating the floor by attaching a coating with insulation function on the surface of the traditional board. In the prior art, fillers with hollow or porous structures are mostly used as insulation materials, such as hollow glass microspheres, aerogels, zeolites, vermiculite, etc., which can improve the insulation performance of the floor to a certain extent, but these insulation fillers are difficult to form a continuous insulation layer in the coating. Generally, the amount of insulation fillers is too large to form a good insulation effect, and the introduction of a large amount of insulation fillers leads to the deterioration of the flexibility of the coating, resulting in poor protection of the board, and the failure of the protection of the coating easily causes the board to get damp and rot. Summary of the invention

[0004] In order to solve the technical problems mentioned in the background technology, the object of the present invention is to provide a thermal insulation floor for building and a preparation method thereof.

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

[0006] A thermal insulation floor for building, consisting of a substrate and a thermal insulation coating on the surface, wherein the thermal insulation coating is formed by curing a thermal insulation coating and comprises, by weight, 100 parts of acrylic emulsion, 16-22 parts of microporous composite filler, 0.2-0.3 parts of wetting dispersant, 0.1-0.15 parts of leveling agent, 0.3-0.4 parts of anti-settling agent and 15-20 parts of diluent.

[0007] Wherein, the microporous composite filler is prepared by the following method:

[0008] Step A1: premix silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran, then add graphene oxide to disperse, introduce dry nitrogen protection, heat to 65-70°C, stir at 40-60rpm, reflux for 2.5-3h, centrifuge to remove supernatant after reaction, and dry to obtain modified graphene;

[0009] Furthermore, the usage ratio of graphene oxide, silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran is 10g:1.2-1.8mL:2-3mL:25-40mL. In an anhydrous environment, triethylamine promotes the ring opening of the epoxy structure of the silane coupling agent KH-560 and the oxygen-containing groups of graphene oxide, and introduces methoxysilane modification to the surface of the graphene sheet.

[0010] Step A2: Disperse the modified graphene in deionized water, adjust the pH value to 2-3 with sulfuric acid, raise the temperature to 55-65°C, apply stirring at 180-240rpm, slowly add sodium silicate solution to react for 4-6h, then add magnesium sulfate and aluminum sulfate solution to continue the reaction for 1.5-2h, then neutralize with sodium hydroxide solution, let stand for 24h, take the bottom precipitate and dry it to obtain a composite precursor;

[0011] Furthermore, the dosage ratio of modified graphene, sodium silicate, magnesium sulfate, aluminum sulfate and deionized water is 1g:3.5-5g:1.5-2g:1.8-2.5g:55-70mL, and the methoxysilane and sodium silicate on the surface of the modified graphene are hydrolyzed and condensed together to form polysilicate on the surface of the graphene sheet, which is then cross-linked and composited with aluminum ions and magnesium ions.

[0012] Preferably, the modulus of the sodium silicate is not higher than 3, and the molar concentration of the sodium silicate solution is not higher than 0.2 mol / L, in which case the sodium silicate can be fully hydrolyzed and polymerized.

[0013] Step A3: placing the composite precursor in a calcining furnace, slowly heating it to 550-620°C and calcining it for 2-2.5h, then quickly heating it to 900-950°C and continuing calcining for 1.2-1.5h, cooling it to below 300°C in the furnace and air cooling it, and breaking it up to obtain a microporous composite filler;

[0014] Preferably, the slow heating rate is no higher than 10°C / min, and the fast heating rate is 15-20°C / min. During the slow heating process, the surface adsorbed water and crystallized water of the composite precursor are slowly precipitated, which is conducive to the formation of uniform voids. The fast heating and calcination in a short time is conducive to the strengthening of the pore wall and is not easy to collapse.

[0015] Preferably, the anti-settling agent is microcrystalline cellulose.

[0016] Preferably, the diluent is ethanol.

[0017] A method for preparing a thermal insulation floor for a building comprises the following steps:

[0018] Step S1: premixing a microporous composite filler, a wetting and dispersing agent, a leveling agent, an anti-settling agent and a diluent, adding an acrylic emulsion, mixing evenly, and vacuum degassing to obtain a thermal insulation coating;

[0019] Step S2: Scrape the thermal insulation coating onto the surface of the substrate, transfer it into a tunnel oven for baking and curing, and obtain a thermal insulation floor for construction.

[0020] Beneficial effects of the present invention:

[0021] The invention discloses a microporous composite filler, which is compounded with an existing acrylic emulsion to prepare a thermal insulation coating, and is applied in floor coating to give the floor good thermal insulation performance; the microporous composite filler uses graphene oxide with a large flake diameter as a carrier, and the epoxy structure of a silane coupling agent KH-560 and the oxygen-containing groups of the graphene oxide are ring-opened, and methoxysilane is introduced into the surface of the graphene sheet for modification, and then sodium silicate and the methoxysilane on the surface of the graphene sheet are hydrolyzed and condensed together to form polysilicic acid on the surface of the graphene sheet, and then the polysilicic acid is cross-linked with aluminum ions and magnesium ions, and finally a porous silicon-magnesium-aluminum composite layer is formed on the surface of the graphene sheet by calcination; the microporous composite filler is used as a carrier, and the epoxy structure of the silane coupling agent KH-560 and the oxygen-containing groups of the graphene oxide are ring-opened, and methoxysilane is introduced into the surface of the graphene sheet for modification, and then sodium silicate and the methoxysilane on the surface of the graphene sheet are hydrolyzed and condensed to form polysilicic acid on the surface of the graphene sheet, and then the polysilicic acid is cross-linked with aluminum ions and magnesium ions, and finally a porous silicon-magnesium-aluminum composite layer is formed on the surface of the graphene sheet by calcination; The porous structure of the surface of the composite filler has good thermal insulation properties. Compared with traditional porous fillers, the microporous composite filler has a flaky structure and is dispersed in the thermal insulation coating to form countless line-surface and surface-surface shielding protection structures. The surfaces of these structures are all porous with good thermal insulation properties, thereby forming a large number of thermal insulation barriers in the thermal insulation coating, greatly reducing the thermal conductivity of the coating and improving the thermal insulation performance of the floor. In addition, the core layer of the microporous composite filler is a graphene sheet, which has excellent anti-penetration properties, giving the thermal insulation barrier good water resistance, effectively reducing the water absorption of the acrylic-based thermal insulation coating, effectively preventing the floor from moisture and rot, and helping to increase the service life of the floor. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1, preparing a thermal insulation floor for construction, the specific implementation process is as follows:

[0024] (1) Preparation method of microporous composite filler

[0025] Step A1: premix the silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran, then add graphene oxide to disperse, introduce dry nitrogen protection, heat to 70°C, stir at 60rpm, and reflux for 2.5h, wherein the graphene oxide is selected from XF002-3 large-diameter graphene oxide, and the amount ratio of graphene oxide, silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran is 10g:1.8mL:3mL:40mL. After the reaction is completed, centrifuge to remove the supernatant and dry to obtain modified graphene.

[0026] Step A2: Disperse the modified graphene in deionized water, adjust the pH value to 2 with sulfuric acid, heat to 65°C, stir at 240rpm, prepare sodium silicate with a modulus of about 2.2 to prepare a sodium silicate solution with a molar concentration of 0.15 mol / L, slowly add the sodium silicate solution, control the addition time to 2h, continue the constant temperature reaction after complete addition, and control the total addition reaction time of the sodium silicate solution to 4h, then prepare magnesium sulfate and aluminum sulfate into a saturated aqueous solution and add it to continue the reaction for 1.5h, finally neutralize with sodium hydroxide solution, and let it stand for 24h, wherein the amount ratio of modified graphene, sodium silicate, magnesium sulfate, aluminum sulfate and deionized water is 1g:5g:1.5g:2.5g:70mL, take the bottom precipitate after standing and dry it to obtain a composite precursor.

[0027] Step A3: Place the composite precursor in a calcination furnace, control the heating rate to be 8°C / min, slowly heat it to 620°C and bake it for 2h, then quickly heat it to 900°C at 15°C / min and continue baking for 1.5h, cool it to below 300°C in the furnace and air cool it, and then break it up to obtain a microporous composite filler.

[0028] (2) Preparation of thermal insulation floor for building

[0029] Step S1: taking raw materials according to weight parts, 100 parts of acrylic emulsion, Uacryl-4718 type single-component acrylic emulsion is used in the implementation process; 16 parts of microporous composite filler, which is self-made in this embodiment; 0.2 parts of wetting dispersant, ANTI-TERRA-250 type water-based raw material is used in the implementation process; 0.1 parts of leveling agent, KMT-5502 type silicone leveling agent is used in the implementation process; 0.3 parts of anti-settling agent, industrial grade microcrystalline cellulose is used in the implementation process; 15 parts of diluent, industrial grade ethanol is used in the implementation process; microporous composite filler, wetting dispersant, leveling agent, anti-settling agent and diluent are premixed at a high speed of 600 rpm for 5 minutes, and then the acrylic emulsion is added and mixed at 40 rpm, and vacuum degassing is performed to obtain a thermal insulation coating.

[0030] Step S2: Scrape the thermal insulation coating onto the surface of the substrate, transfer it into a tunnel oven for baking and curing, and the baking temperature process is: the temperature of zone 1 is 40°C, and the baking time is 5 minutes; the temperature of zone 2 is 55°C, and the baking time is 2 minutes; the temperature of zone 3 is 60°C, and the baking time is 1 minute; the temperature of zone 4 is 45°C, and the baking time is 3 minutes. The thermal insulation coating is cured into a thermal insulation coating to obtain a thermal insulation floor for construction.

[0031] Example 2, preparing a thermal insulation floor for construction, the specific implementation process is as follows:

[0032] (1) Preparation method of microporous composite filler

[0033] Step A1: premix the silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran, then add graphene oxide to disperse, introduce dry nitrogen protection, heat to 65°C, stir at 40rpm, and reflux for 3h, wherein the graphene oxide is selected from XF002-3 large-diameter graphene oxide, and the amount ratio of graphene oxide, silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran is 10g:1.2mL:2mL:25mL. After the reaction is completed, centrifuge to remove the supernatant and dry to obtain modified graphene.

[0034] Step A2: Disperse the modified graphene in deionized water, adjust the pH value to 3 with sulfuric acid, heat to 55°C, stir at 180rpm, prepare sodium silicate with a modulus of about 2.2 to prepare a sodium silicate solution with a molar concentration of 0.15 mol / L, slowly add the sodium silicate solution, control the addition time to 3 hours, continue the constant temperature reaction after complete addition, and control the total addition reaction time of the sodium silicate solution to 6 hours, then prepare magnesium sulfate and aluminum sulfate into a saturated aqueous solution and add it to continue the reaction for 2 hours, finally neutralize with sodium hydroxide solution, and let it stand for 24 hours, wherein the amount ratio of modified graphene, sodium silicate, magnesium sulfate, aluminum sulfate and deionized water is 1g:3.5g:2g:1.8g:55mL, take the bottom precipitate after standing and dry it to obtain a composite precursor.

[0035] Step A3: Place the composite precursor in a calcination furnace, control the heating rate to be 6°C / min, slowly heat up to 550°C and bake for 2.5h, then quickly heat up to 950°C at 20°C / min and continue baking for 1.2h, cool to below 300°C in the furnace and air cool, and break up to obtain a microporous composite filler.

[0036] (2) Preparation of thermal insulation floor for building

[0037] Step S1: taking raw materials according to weight parts, 100 parts of acrylic emulsion, Uacryl-4718 type single-component acrylic emulsion is used in the implementation process; 22 parts of microporous composite filler, which is self-made in this embodiment; 0.3 parts of wetting dispersant, ANTI-TERRA-250 type water-based raw material is used in the implementation process; 0.15 parts of leveling agent, KMT-5502 type silicone leveling agent is used in the implementation process; 0.4 parts of anti-settling agent, industrial grade microcrystalline cellulose is used in the implementation process; 20 parts of diluent, industrial grade ethanol is used in the implementation process; microporous composite filler, wetting dispersant, leveling agent, anti-settling agent and diluent are premixed at a high speed of 600 rpm for 8 minutes, and then the acrylic emulsion is added and mixed at 40 rpm, and vacuum degassing is performed to obtain a thermal insulation coating.

[0038] Step S2: Scrape the thermal insulation coating onto the surface of the substrate, transfer it into a tunnel oven for baking and curing, and the baking temperature process is: the temperature of zone 1 is 40°C, and the baking time is 5 minutes; the temperature of zone 2 is 55°C, and the baking time is 2 minutes; the temperature of zone 3 is 60°C, and the baking time is 1 minute; the temperature of zone 4 is 45°C, and the baking time is 3 minutes. The thermal insulation coating is cured into a thermal insulation coating to obtain a thermal insulation floor for construction.

[0039] Example 3, preparing a thermal insulation floor for construction, the specific implementation process is as follows:

[0040] (1) Preparation method of microporous composite filler

[0041] Step A1: premix the silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran, then add graphene oxide to disperse, introduce dry nitrogen protection, heat to 68°C, stir at 60rpm, and reflux for 2.7h, wherein the graphene oxide is selected from XF002-3 large-diameter graphene oxide, and the amount ratio of graphene oxide, silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran is 10g:1.4mL:2mL:35mL. After the reaction is completed, centrifuge to remove the supernatant and dry to obtain modified graphene.

[0042] Step A2: Disperse the modified graphene in deionized water, adjust the pH value to 2 with sulfuric acid, heat to 60°C, stir at 180rpm, prepare sodium silicate with a modulus of about 2.2 to prepare a sodium silicate solution with a molar concentration of 0.15 mol / L, slowly add the sodium silicate solution, control the addition time to 2.2h, continue the constant temperature reaction after complete addition, and control the total addition reaction time of the sodium silicate solution to 5.5h, then prepare magnesium sulfate and aluminum sulfate into a saturated aqueous solution and add it to continue the reaction for 1.8h, finally neutralize with sodium hydroxide solution, and let it stand for 24h, wherein the amount ratio of modified graphene, sodium silicate, magnesium sulfate, aluminum sulfate and deionized water is 1g:4.5g:1.6g:2.2g:65mL, take the bottom precipitate after standing and dry it to obtain a composite precursor.

[0043] Step A3: Place the composite precursor in a calcination furnace, control the heating rate to be 10°C / min, slowly heat it to 600°C, and bake it for 2.2h, then quickly heat it to 920°C at 18°C / min and continue baking for 1.4h, cool it to below 300°C in the furnace, and air cool it to obtain a microporous composite filler after breaking it up.

[0044] (2) Preparation of thermal insulation floor for building

[0045] Step S1: taking raw materials according to weight parts, 100 parts of acrylic emulsion, Uacryl-4718 type single-component acrylic emulsion is used in the implementation process; 18 parts of microporous composite filler, which is self-made in this embodiment; 0.25 parts of wetting and dispersing agent, ANTI-TERRA-250 type water-based raw material is used in the implementation process; 0.12 parts of leveling agent, KMT-5502 type silicone leveling agent is used in the implementation process; 0.35 parts of anti-settling agent, industrial grade microcrystalline cellulose is used in the implementation process; 17 parts of diluent, industrial grade ethanol is used in the implementation process; microporous composite filler, wetting and dispersing agent, leveling agent, anti-settling agent and diluent are premixed at a high speed of 600 rpm for 7 minutes, and then the acrylic emulsion is added and mixed at 40 rpm, and vacuum degassing is performed to obtain a thermal insulation coating.

[0046] Step S2: Scrape the thermal insulation coating onto the surface of the substrate, transfer it into a tunnel oven for baking and curing, and the baking temperature process is: the temperature of zone 1 is 40°C, and the baking time is 5 minutes; the temperature of zone 2 is 55°C, and the baking time is 2 minutes; the temperature of zone 3 is 60°C, and the baking time is 1 minute; the temperature of zone 4 is 45°C, and the baking time is 3 minutes. The thermal insulation coating is cured into a thermal insulation coating to obtain a thermal insulation floor for construction.

[0047] Example 4, preparing a thermal insulation floor for construction, the specific implementation process is as follows:

[0048] (1) Preparation method of microporous composite filler

[0049] Step A1: premix the silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran, then add graphene oxide to disperse, introduce dry nitrogen protection, heat to 66°C, stir at 60rpm, and reflux for 3h, wherein the graphene oxide is selected from XF002-3 large-diameter graphene oxide, and the amount ratio of graphene oxide, silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran is 10g:1.6mL:3mL:30mL. After the reaction is completed, centrifuge to remove the supernatant and dry to obtain modified graphene.

[0050] Step A2: Disperse the modified graphene in deionized water, adjust the pH value to 3 with sulfuric acid, heat to 60°C, stir at 240rpm, prepare sodium silicate with a modulus of about 2.2 to prepare a sodium silicate solution with a molar concentration of 0.15 mol / L, slowly add the sodium silicate solution, control the addition time to 3 hours, continue the constant temperature reaction after complete addition, and control the total addition reaction time of the sodium silicate solution to 5 hours, then prepare magnesium sulfate and aluminum sulfate into a saturated aqueous solution and add it to continue the reaction for 1.8 hours, finally neutralize with sodium hydroxide solution, and let it stand for 24 hours, wherein the amount ratio of modified graphene, sodium silicate, magnesium sulfate, aluminum sulfate and deionized water is 1g:4.2g:1.6g:2g:65mL, take the bottom precipitate after standing and dry it to obtain a composite precursor.

[0051] Step A3: Place the composite precursor in a calcination furnace, control the heating rate to be 8°C / min, slowly heat up to 580°C and bake for 2.2h, then quickly heat up to 900°C at 18°C / min and continue to bake for 1.5h, cool to below 300°C in the furnace and air cool, and break up to obtain a microporous composite filler.

[0052] (2) Preparation of thermal insulation floor for building

[0053] Step S1: taking raw materials according to weight parts, 100 parts of acrylic emulsion, Uacryl-4718 type single-component acrylic emulsion is used in the implementation process; 20 parts of microporous composite filler, which is self-made in this embodiment; 0.25 parts of wetting and dispersing agent, ANTI-TERRA-250 type water-based raw material is used in the implementation process; 0.13 parts of leveling agent, KMT-5502 type silicone leveling agent is used in the implementation process; 0.35 parts of anti-settling agent, industrial grade microcrystalline cellulose is used in the implementation process; 18 parts of diluent, industrial grade ethanol is used in the implementation process; microporous composite filler, wetting and dispersing agent, leveling agent, anti-settling agent and diluent are premixed at a high speed of 600 rpm for 7 minutes, and then the acrylic emulsion is added and mixed at 40 rpm, and vacuum degassing is performed to obtain a thermal insulation coating.

[0054] Step S2: Scrape the thermal insulation coating onto the surface of the substrate, transfer it into a tunnel oven for baking and curing, and the baking temperature process is: the temperature of zone 1 is 40°C, and the baking time is 5 minutes; the temperature of zone 2 is 55°C, and the baking time is 2 minutes; the temperature of zone 3 is 60°C, and the baking time is 1 minute; the temperature of zone 4 is 45°C, and the baking time is 3 minutes. The thermal insulation coating is cured into a thermal insulation coating to obtain a thermal insulation floor for construction.

[0055] Comparative Example 1

[0056] This comparative example refers to Example 4, except that the microporous composite filler is replaced with hollow glass microspheres of the same weight, with an average particle size of 10 μm, and the rest of the implementation process is the same as Example 4.

[0057] Comparative Example 2

[0058] This comparative example refers to Example 4, except that the microporous composite filler is replaced with the same weight portion of zeolite powder with a fineness of 325 mesh, 0.3 portion of graphene oxide is added, and the rest of the implementation process is the same as Example 4.

[0059] In order to detect the performance improvement effect of the thermal insulation coating on the floor, the thermal insulation coating prepared in the above implementation process was scraped on a glass sheet sprayed with a release agent, and formed into a sheet after curing. The thermal conductivity of the sheet was tested with reference to the GB / T 42919.4-2023 standard; the water absorption of the sheet was tested with reference to the GB / T 1034-2008 standard; and the flexibility of the sheet was tested with reference to the GB / T 1731-2020 standard. The specific test results are shown in the following table:

[0060]

[0061] From the test results in the above table, it can be seen that the thermal conductivity of the floor insulation coating of the present invention is 0.0791-0.0855 W / (m·K), with low thermal conductivity and heat preservation performance, the water absorption rate is 1.93-2.29%, with low water absorption, and the flexibility can reach 2# axis (R10) without cracking, and has good flexibility.

[0062] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0063] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A thermal insulation floor for building, consisting of a substrate and a thermal insulation coating on the surface, characterized in that: The thermal insulation coating is formed by curing the thermal insulation coating, and the thermal insulation coating comprises, by weight: 100 parts of acrylic emulsion, 16-22 parts of microporous composite filler, 0.2-0.3 parts of wetting dispersant, 0.1-0.15 parts of leveling agent, 0.3-0.4 parts of anti-settling agent and 15-20 parts of diluent; The microporous composite filler is prepared by the following method: Step A1: premix silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran, add graphene oxide to disperse, introduce dry nitrogen protection, heat to 65-70°C, stir and reflux for reaction for 2.5-3h, centrifuge to remove supernatant and dry after the reaction to obtain modified graphene; Step A2: Disperse the modified graphene in deionized water, adjust the pH value to 2-3 with sulfuric acid, heat to 55-65°C, stir and slowly add sodium silicate solution to react for 4-6 hours, then add magnesium sulfate and aluminum sulfate solution to continue the reaction for 1.5-2 hours, then neutralize with sodium hydroxide solution, let stand for 24 hours, take the bottom precipitate and dry it to obtain a composite precursor; Step A3: Place the composite precursor in a calcination furnace, slowly heat it up to 550-620°C and calcine for 2-2.5h, then quickly heat it up to 900-950°C and continue calcining for 1.2-1.5h, cool it to below 300°C in the furnace and air cool it, and break it up to obtain a microporous composite filler, wherein the slow heating rate is not higher than 10°C / min, and the fast heating rate is 15-20°C / min.

2. A thermal insulation floor for building according to claim 1, characterized in that: The usage ratio of graphene oxide, silane coupling agent KH-560, triethylamine and anhydrous tetrahydrofuran is 10g:1.2-1.8mL:2-3mL:25-40mL.

3. A thermal insulation floor for building according to claim 2, characterized in that: The dosage ratio of modified graphene, sodium silicate, magnesium sulfate, aluminum sulfate and deionized water is 1g:3.5-5g:1.5-2g:1.8-2.5g:55-70mL.

4. The thermal insulation floor for building according to claim 3, characterized in that: The modulus of sodium silicate is not higher than 3, and the molar concentration of the sodium silicate solution is not higher than 0.2 mol / L.

5. The thermal insulation floor for building according to claim 1, characterized in that: The anti-settling agent is microcrystalline cellulose.

6. The thermal insulation floor for building according to claim 1, characterized in that: The diluent is ethanol.

7. A method for preparing a thermal insulation floor for construction according to any one of claims 1 to 6, characterized in that: The steps include: Step S1: premixing a microporous composite filler, a wetting and dispersing agent, a leveling agent, an anti-settling agent and a diluent, adding an acrylic emulsion, mixing evenly, and vacuum degassing to obtain a thermal insulation coating; Step S2: Scrape the thermal insulation coating onto the surface of the substrate, transfer it into a tunnel oven for baking and curing, and obtain a thermal insulation floor for construction.

Images