A high-efficiency thermal insulation floor based on graphene and a production process thereof

Abstract

This invention discloses a graphene-based high-efficiency thermal insulation floor and its manufacturing process, relating to the field of building materials technology. The high-efficiency thermal insulation floor uses wood as a substrate and is coated with a graphene thermally conductive slurry. The graphene thermally conductive slurry comprises the following raw materials in parts by weight: 4-6 parts modified graphene, 25-30 parts epoxy resin E44, 2-3 parts micron-sized aluminum nitride, 3-5 parts modified expanded vermiculite, 0.8-1.2 parts titanate coupling agent NDZ-105, 0.3-0.6 parts sodium lignosulfonate, 0.2-0.4 parts mineral oil defoamer, 28-35 parts deionized water, 15-20 parts ethanol, 0.5-0.8 parts silane coupling agent KH-570, and 1-2 parts nano-silica. This flooring utilizes the synergistic effect of modified graphene and micron-sized aluminum nitride to significantly enhance thermal conductivity and insulation performance, meeting indoor temperature control requirements. The wood is degreased, ensuring strict control over density and moisture content, effectively reducing deformation and cracking. The slurry viscosity is adjustable, and the coating parameters are clearly defined. The modified expanded vermiculite is tightly bonded to the resin, balancing waterproofing and structural strength, significantly extending service life and demonstrating excellent performance.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a high-efficiency thermal insulation floor based on graphene and its production process. Background Technology

[0002] In the field of building materials, flooring, as a core component of interior decoration, not only needs to meet basic load-bearing and wear-resistance requirements, but also, with the popularization of green building and energy-saving housing concepts, thermal insulation has gradually become a key demand. Currently, most mainstream insulated flooring on the market relies on traditional insulation materials such as extruded polystyrene (XPS) boards and rock wool composite substrates, which have significant technical shortcomings. On the one hand, traditional insulation materials have poor compatibility with flooring substrates such as solid wood and composite boards, easily leading to delamination and detachment due to thermal expansion and contraction. This results in a significant decrease in insulation performance over time, with the thermal conductivity typically increasing by more than 20% after 3-5 years, making it difficult to meet the long-term requirements for stable indoor temperature control. On the other hand, some insulated flooring excessively increases the thickness of the insulation layer to improve insulation performance, which not only increases installation space requirements but also easily leads to a decrease in the overall structural stability of the flooring. The bending strength is generally below 15 MPa, failing to meet the durability requirements of daily household foot traffic.

[0003] Meanwhile, traditional flooring substrates such as ordinary solid wood and MDF often lack targeted pretreatment, resulting in a wide range of moisture content fluctuations, frequently reaching 15%-20%. In indoor environments with frequent temperature and humidity changes, this makes them prone to warping and cracking, further compromising the integrity of the insulation layer. Furthermore, current insulation flooring production processes suffer from low viscosity control precision for functional slurries such as thermally conductive and adhesive slurries, relying heavily on experience for adjustments. This leads to uneven coating thickness and localized insulation performance differences exceeding 30%, making standardized mass production difficult. In addition, most products lack waterproofing and anti-aging designs, making them susceptible to substrate mold growth and insulation layer moisture absorption failure in humid environments. Their lifespan is generally less than 8 years, failing to meet the long-term needs of modern residences.

[0004] Against this backdrop, developing a flooring product that combines high-efficiency insulation, structural stability, controllable processes, and high durability has become a key direction for solving the current pain points of traditional insulation flooring technology and promoting the upgrading of building energy-saving materials. It also meets the market's urgent demand for high-performance, long-life interior decoration materials. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a graphene-based high-efficiency thermal insulation floor and its manufacturing process, solving the problems of rapid thermal insulation performance degradation, insufficient structural stability, and non-standard manufacturing processes in traditional thermal insulation floors.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A high-efficiency thermal insulation floor based on graphene is made of rockwood as the substrate and coated with graphene thermal conductive paste. The graphene thermal conductive paste contains the following raw materials in parts by weight: 4-6 parts modified graphene, 25-30 parts epoxy resin E44, 2-3 parts micron-sized aluminum nitride, 3-5 parts modified expanded vermiculite, 0.8-1.2 parts titanate coupling agent NDZ-105, 0.3-0.6 parts sodium lignosulfonate, 0.2-0.4 parts mineral oil defoamer, 28-35 parts deionized water, 15-20 parts ethanol, 0.5-0.8 parts silane coupling agent KH-570, and 1-2 parts nano silica.

[0007] Furthermore, the modified graphene powder is prepared using the following specific steps: A1. Take graphene powder and add 31% hydrochloric acid by mass. Stir at 200-250 r / min for 20-25 min at room temperature, then heat to 45-50℃ and continue stirring for 1.5-2 h. After the reaction, slowly add deionized water to dilute, stir for 10 min, let stand for 30 min, pour off the supernatant, keep the lower graphene slurry, add industrial grade urea to the slurry, stir and heat to 60-65℃, stir at 300-350 r / min for 2-2.5 h. After the reaction, filter, wash the filter cake with deionized water until pH=5-6, and dry in an oven at 80-85℃ for 3-3.5 h to obtain oxidized intercalated graphene. First, 31% hydrochloric acid is used to etch the graphene surface at room temperature to generate oxygen-containing functional groups. After heating, the etching is strengthened to form micropores. Industrial-grade urea is used at 60-65℃ to form hydrogen bonds with the oxygen-containing functional groups of graphene through amino groups, inserting into the interlayer gaps to expand the interlayer spacing and weaken van der Waals forces. The residual hydrochloric acid is washed away, and the oxide-intercalation structure is fixed by drying at 80-85℃ to prevent the layers from recombinizing.

[0008] A2. Add oxide-intercalated graphene to deionized water and ultrasonically disperse for 20-25 min; add corn starch, stir and heat to 70-75℃, add hydrochloric acid dropwise to adjust pH=3-4, and stir at 300-350 r / min for 3-3.5 h; add micron-sized aluminum nitride to the system and continue stirring for 1-1.5 h; after the reaction, filter, wash the filter cake twice with deionized water, and dry it in an oven at 75-80℃ for 2.5-3 h to obtain starch-aluminum nitride modified graphene; Ultrasonic cavitation breaks up the agglomeration of oxidized-intercalated graphene, making it uniformly dispersed; under acidic conditions at 70-75℃, corn starch hydrolyzes to produce glucose, and the glucose hydroxyl groups form hydrogen bonds or ester bonds with the oxygen-containing functional groups of graphene, forming a starch coating layer to improve compatibility with resin; micron-sized aluminum nitride fills the gaps between graphene sheets through van der Waals forces to form a three-dimensional composite thermally conductive network, reducing heat loss.

[0009] A3. Add starch-aluminum nitride modified graphene to 95% ethanol and stir to disperse for 10 min. Then add potassium dihydrogen phosphate, heat to 55-60℃, and stir at 250-300 r / min for 2-2.5 h. After filtration, wash the filter cake once with ethanol and dry at 70℃ for 1 h. Separately, take epoxy resin E44, add deionized water, stir to dissolve, add modified amine curing agent, and stir for 10 min to obtain a prepolymer. Add the dried graphene powder to the prepolymer, heat to 65-70℃, and stir at 300 r / min for 3-3.5 h. After the reaction, filter and dry the filter cake in an oven at 85-90℃ for 3 h to obtain the final modified graphene.

[0010] At 55-60℃, the phosphate group of potassium dihydrogen phosphate forms a coordination bond with the starch hydroxyl group on the graphene surface, which improves the thermal stability after modification; epoxy resin E44 and modified amine curing agent undergo a ring-opening reaction to generate a prepolymer; at 65-70℃, the prepolymer reacts with the surface groups of graphene through epoxy groups and hydroxyl groups to achieve chemical coating and enhance the interfacial bonding force with the resin matrix.

[0011] Furthermore, the ratio of graphene powder, hydrochloric acid, deionized water, and industrial-grade urea in A1 is 10-15g: 150-200mL: 300-350mL: 6-9g.

[0012] Furthermore, the ratio of deionized water, corn starch, and micron-sized aluminum nitride in A2 is 120-150 mL: 4-6 g: 2-3 g.

[0013] Furthermore, the ratio of ethanol, potassium dihydrogen phosphate, epoxy resin E44, deionized water, and modified amine curing agent in A3 is 80-100mL: 3-5g: 8-10g: 20-30mL: 1-2g.

[0014] Furthermore, the modified amine curing agent in A3 is prepared by the following method: 20-30g of ethylenediamine is added to 5-8g of propylene oxide, and stirred at 200-250r / min for 30-40min, during which the temperature is controlled not to exceed 40℃. Then, 3-5g of xylene is added and stirring is continued for 15-20min. Then, glacial acetic acid is added dropwise to adjust the pH to 7, and after stirring for 10min, it is allowed to stand for 20min to remove a small amount of layered impurities, thus obtaining the modified amine curing agent. Ethylenediamine provides the amino group, and propylene oxide, under stirring at 200-250 r / min, opens the epoxy ring to introduce hydroxyl groups, reducing the volatility of ethylenediamine and improving its compatibility with epoxy resin E44. Temperature control is maintained at ≤40℃ to avoid excessive exothermic reaction leading to carbonization of the system. Xylene adjusts the viscosity of the curing agent, facilitating subsequent mixing with the epoxy resin. Glacial acetic acid is used to adjust the pH to 7 to neutralize excess amino groups, preventing pH fluctuations during prepolymer preparation from affecting the graphene coating effect. Static removal removes impurities to ensure the purity of the curing agent and the stability of the prepolymer performance.

[0015] Furthermore, the modified expanded vermiculite is prepared using the following specific steps: B1. Take expanded vermiculite and add it to a 10% sodium hydroxide solution. Stir at 150-200 r / min for 1-1.5 h at room temperature. After filtration, wash with deionized water until pH=7-8, and dry in an oven at 100-105℃ for 2 h. Take sodium silicate, add it to deionized water, stir to dissolve and obtain sodium silicate solution. Add the dried vermiculite to the solution, stir at room temperature for 30-40 min, remove the vermiculite, drain it and dry in an oven at 110-120℃ for 1.5-2 h to obtain sodium silicate coated vermiculite. A 10% sodium hydroxide solution is used to etch the surface of expanded vermiculite, removing impurities and increasing the specific surface area. Sodium silicate is hydrolyzed to generate silicic acid, and the hydroxyl groups of silicic acid undergo a condensation reaction with the silanol groups on the vermiculite surface to form a siloxane coating layer. Drying at 110-120℃ accelerates the condensation, and the solidified coating layer enhances the water resistance and structural strength of the vermiculite.

[0016] B2. Take sodium silicate-coated vermiculite, add it to deionized water, stir and disperse for 5 min, add polyvinyl alcohol, heat to 80-85℃, stir at 200-250 r / min for 2-2.5 h, then add maleic anhydride to the system, continue to heat to 90-95℃, stir for 2-2.5 h, filter after completion, and dry in an oven at 95-100℃ for 2 h to obtain polyvinyl alcohol-maleic anhydride modified expanded vermiculite; At 80-85℃, the hydroxyl groups of polyvinyl alcohol form hydrogen bonds with the silanol groups on the vermiculite surface, adsorbing to form an organic coating layer and improving compatibility with the resin; at 90-95℃, the carboxyl groups of maleic anhydride and the hydroxyl groups of polyvinyl alcohol undergo esterification reaction, and the double bonds polymerize simultaneously to form a cross-linked network, enhancing the mechanical strength of vermiculite and the stability of the coating layer.

[0017] B3. Add polyvinyl alcohol-maleic anhydride modified expanded vermiculite to deionized water and stir at 150-200 r / min for 5 min at room temperature to form a stable suspension. Then add 30% solid content water-based paraffin emulsion and increase the stirring speed to 200-250 r / min. Stir at room temperature for 30-40 min. Then add zinc borate powder and continue stirring at 200-250 r / min for 1-1.5 h. After stirring, filter and wash the filter cake once with deionized water. Dry it in an oven at 80-85℃ for 1.5-2 h to obtain modified expanded vermiculite.

[0018] Increasing the stirring speed allows the water-based paraffin emulsion particles to be evenly adsorbed onto the vermiculite surface, forming a hydrophobic film that repels water molecules. Zinc borate is evenly dispersed on the vermiculite surface and pores through physical adsorption, and decomposes at high temperature to generate a flame-retardant film that isolates oxygen and heat and inhibits free radicals. Drying at 80-85℃ fixes the hydrophobic film and zinc borate, ensuring stable waterproof and flame-retardant performance.

[0019] Furthermore, the ratio of expanded vermiculite, sodium hydroxide solution, sodium silicate, and deionized water in B1 is 20-30g: 200-250mL: 5-7g: 80-100mL.

[0020] Furthermore, the ratio of deionized water, polyvinyl alcohol, and maleic anhydride in B2 is 150-200mL: 4-6g: 1-2g.

[0021] Furthermore, the ratio of deionized water, aqueous paraffin emulsion, and zinc borate powder in B3 is 150-200mL: 8-12g: 2-3g.

[0022] A manufacturing process for a high-efficiency thermal insulation floor based on graphene specifically includes the following steps: S1. Add silane coupling agent KH-570 to ethanol and stir for 10 minutes to prepare a waterproofing solution. Apply the solution evenly to the degreased rock wood, applying two coats with a 5-minute interval to avoid missed areas that may cause localized water seepage. After application, place the rock wood in a ventilated area at 20-25℃ for 30-40 minutes to allow the ethanol to evaporate, fix the waterproof membrane, and prevent the membrane from cracking due to high-temperature drying. Finally, sand the surface of the substrate with 180-grit sandpaper to obtain the pretreated rock wood. S2. Add modified graphene, micron-sized aluminum nitride, and modified expanded vermiculite to deionized water and ultrasonically disperse for 30-35 minutes, stirring once every 10 minutes to break up filler agglomeration and prevent sedimentation, ensuring uniform dispersion of the mixed filler to obtain a mixed filler dispersion; separately, add titanate coupling agent NDZ-105 to deionized water and stir for 10 minutes to prepare a coupling agent solution; add epoxy resin E44 to a mixing tank, stir at 800-1000 r / min for 5 minutes, then pour in the coupling agent solution and continue stirring for 15-2 minutes. Add sodium lignosulfonate and mineral oil defoamer and stir for 10 minutes to obtain the resin base. Pour the mixed filler dispersion into the resin base and stir at 1500-1800 r / min for 30-35 minutes. Finally, add nano silica and stir for 15 minutes to ensure that the resin and coupling agent are fully mixed first, and then stir at high intensity to fuse the filler and resin base, avoiding uneven thermal insulation and mechanical properties caused by local agglomeration. Filter through 200 mesh to ensure the uniformity of the slurry and avoid coating defects, to obtain the graphene thermally conductive slurry. S3. Adjust the spacing between the coating rollers of the roller coater to 0.3-0.5mm. Too thick a layer will easily crack, while too thin a layer will not provide sufficient insulation. The coating speed should be 1-1.5m / min to ensure that the slurry evenly covers the substrate. Lay the pretreated rock and wood flat on the conveyor belt, coat it evenly with graphene thermal conductive slurry, and let it stand for 5-10 minutes after coating to reduce air bubbles and improve the density of the insulation layer. S4. Place the coated rock wood in an oven at 60-65℃ for 30-35 minutes to dry. Remove and ventilate to cool to room temperature. Then place it back in the oven at 80-85℃ for 30-35 minutes. After that, lower the temperature to 50-55℃ and keep it at that temperature for 20 minutes. Remove and allow to cool naturally to room temperature. Use a gradient temperature increase for drying. First, use a low temperature to remove the surface solvent, then a medium temperature to promote resin curing, and finally a low temperature to set the shape. Avoid direct drying at high temperatures, which may cause the slurry to crack. Ventilate and cool to room temperature to prevent internal stress caused by temperature difference between the substrate and the slurry, reducing the risk of deformation. Lightly sand the surface of the heat-conducting layer with 240-grit sandpaper and wipe off the dust with a dry cloth to obtain the finished flooring.

[0023] Furthermore, the viscosity of the graphene thermally conductive slurry at 25°C is [missing value]. It is suitable for roller coating processes, and its viscosity can be finely adjusted by changing the amount of ethanol used. For every 1 part increase in the amount of ethanol, the viscosity of the slurry can be reduced. .

[0024] Furthermore, the density of the rock wood is 0.65-0.75 g / cm³. 3 To ensure the strength of the substrate, it is necessary to avoid excessively dense and hard materials that are difficult to process or excessively sparse and soft materials that are prone to deformation; the moisture content should be ≤12% to reduce warping and cracking caused by moisture changes during subsequent use; the rock wood is degreased by hot air at 85℃ for 1.5 hours before being used as the substrate to remove internal grease and excess moisture, further reducing the risk of deformation and improving the bonding strength with the slurry; after degreasing, it is naturally cooled to room temperature before being used in the subsequent coating process to avoid the slurry from curing prematurely due to direct coating on the high-temperature substrate; in the cooling process of S4, the cooling rate is controlled at 3-5℃ / min to prevent internal stress from being generated in the substrate and insulation layer due to excessively rapid cooling, ensuring the dimensional stability of the finished product and reducing the risk of cracking.

[0025] This invention provides a high-efficiency thermal insulation floor based on graphene and its manufacturing process, which has the following beneficial effects: 1. This flooring utilizes a synergistic insulation system formed by modified graphene, micron-sized aluminum nitride, and modified expanded vermiculite, ensuring long-term stable insulation performance from both structural and compositional perspectives. Firstly, the modified graphene, after oxidation-intercalation, starch-aluminum nitride coating, and prepolymer modification, forms multi-dimensional heat-conducting channels on its surface, enabling rapid and uniform heat conduction and retention. Micron-sized aluminum nitride, as an auxiliary heat-conducting component, fills the gaps between graphene particles, reducing heat loss channels. The modified expanded vermiculite, through sodium silicate coating, polyvinyl alcohol-maleic anhydride grafting, and water-based paraffin emulsion treatment, forms a porous, closed structure, further blocking heat convection. When these three components are compounded in a specific ratio, they bond tightly with epoxy resin E44 to form a continuous and stable insulation layer, avoiding the delamination problems caused by poor compatibility between traditional insulation materials and the substrate. This allows for long-term adaptation to stable indoor temperature control requirements, reducing energy consumption from air conditioning, heating, and other equipment.

[0026] 2. The flooring's structural performance is enhanced through both substrate treatment and functional layer integration, ensuring long-term durability. The substrate is made of rockwood with a density of 0.65-0.75 g / cm³ and a moisture content of ≤12%, and undergoes a 1.5-hour hot air degreasing treatment at 85℃. This degreasing process removes excess oil and moisture from the rockwood, reducing the risk of warping and cracking due to temperature and humidity changes during subsequent use. Simultaneously, during the pretreatment stage, a waterproofing solution prepared from silane coupling agent KH-570 and ethanol is applied to the substrate surface to form a dense waterproof film. This enhances the adhesion between the substrate and the graphene thermally conductive paste while preventing moisture from penetrating the substrate and damaging its structure. In the functional layer, the titanate coupling agent NDZ-105 and the silane coupling agent KH-570 work synergistically to improve the interfacial bonding state between inorganic fillers such as modified graphene and modified expanded vermiculite and the epoxy resin E44 organic resin matrix, reducing interfacial voids; sodium lignosulfonate, as a dispersant, enables the fillers to be uniformly dispersed in the slurry, avoiding structural weak points caused by local filler agglomeration.

[0027] 3. Through multi-dimensional modification and process design, the flooring possesses excellent waterproof, mildew-resistant, and anti-aging properties, making it suitable for diverse indoor environments such as humid conditions and large temperature and humidity fluctuations. On one hand, the substrate is waterproofed using the silane coupling agent KH-570, the epoxy resin E44 in the functional layer itself has good waterproof properties, and the modified expanded vermiculite, after being coated with water-based paraffin emulsion, further enhances its hydrophobicity. These three elements work synergistically to form a multi-layered waterproof barrier. On the other hand, the modified graphene, after prepolymer modification, forms a stable chemical structure on its surface, significantly improving its anti-aging performance; the zinc borate powder in the modified expanded vermiculite not only enhances thermal insulation performance but also possesses a certain anti-aging effect, slowing down the aging and degradation rate of the resin base material. In addition, the surface of the finished flooring is lightly sanded with 240-grit sandpaper to remove burrs and imperfections, reducing the risk of wear and tear during daily use. Furthermore, the functional layer is tightly bonded to the substrate, making it less prone to coating peeling or substrate damage during daily use such as walking and cleaning. Even in humid areas such as kitchens and bathrooms, or in environments with frequent temperature and humidity fluctuations such as heating in winter and air conditioning in summer in northern regions, it can still maintain stable performance, thus broadening the application range of the flooring.

[0028] 4. Production parameters are clearly defined and controllable throughout the entire process, facilitating mass production. During slurry preparation, the viscosity is controlled at 25℃. The amount of ethanol can be finely adjusted; parameters such as ultrasonic dispersion, stirring speed and duration are precisely limited to ensure uniform mixing of components. In the coating and drying process, the roller spacing, speed, and temperature, duration and cooling rate of each drying stage are standardized to avoid human error, ensure stable performance of different batches of flooring, with local insulation differences ≤5%, improve the finished product qualification rate and reduce production costs. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1: Production of high-efficiency thermal insulation flooring based on graphene, the specific steps are as follows: S1. Take 0.5 parts of silane coupling agent KH-570 and add 15 parts of ethanol, stir for 10 minutes to prepare a waterproofing agent solution, apply it evenly to the degreased rock wood, apply 2 times, with an interval of 5 minutes; after application, place the rock wood in a ventilated place at 20℃ to dry for 30 minutes, and then use 180-grit sandpaper to sand the surface of the substrate to obtain pretreated rock wood. S2. Take 4 parts graphene, 2 parts micron-sized aluminum nitride, and 3 parts expanded vermiculite, add 20 parts deionized water, and ultrasonically disperse for 30 minutes, stirring once every 10 minutes to obtain a mixed filler dispersion. Separately, take 0.8 parts titanate coupling agent NDZ-105, add 8 parts deionized water, and stir for 10 minutes to prepare a coupling agent solution. Add 25 parts epoxy resin E44 to a mixing tank, stir at 800 r / min for 5 minutes, then pour in the coupling agent solution, continue stirring for 15 minutes, then add 0.3 parts sodium lignosulfonate and 0.2 parts mineral oil defoamer, and stir for 10 minutes to obtain a resin base. Pour the mixed filler dispersion into the resin base, stir at 1500 r / min for 30 minutes, and finally add 1 part nano silica, stir for 15 minutes, and filter through a 200-mesh filter to obtain a graphene thermally conductive slurry. S3. Adjust the gap between the coating rollers of the roller coater to 0.3mm, the coating speed to 1m / min, lay the pretreated rock wood flat on the conveyor belt, coat it evenly with graphene thermal conductive slurry, and let it stand for 5 minutes after coating. S4. Place the coated rock wood in a 60℃ oven to dry for 30 minutes, remove it and ventilate to cool to room temperature, then put it back into the oven at 80℃ for 30 minutes, then cool it down to 50℃ and keep it for 20 minutes. The cooling rate is controlled at 3℃ / min. Remove it and let it cool naturally to room temperature. Use 240-grit sandpaper to lightly sand the surface of the heat-conducting layer, and wipe off the dust with a dry cloth to obtain the finished floor.

[0031] Example 2: Production of high-efficiency thermal insulation flooring based on graphene, the specific steps are as follows: S1. Take 0.8 parts of silane coupling agent KH-570 and add 20 parts of ethanol, stir for 10 minutes to prepare a waterproofing agent solution, apply it evenly to the degreased rock wood, apply 2 times, with an interval of 5 minutes; after application, place the rock wood in a ventilated place at 25℃ to dry for 40 minutes, and then use 180-grit sandpaper to sand the surface of the substrate to obtain pretreated rock wood. S2. Take 6 parts graphene, 3 parts micron-sized aluminum nitride, and 5 parts expanded vermiculite, add 25 parts deionized water, and ultrasonically disperse for 35 minutes, stirring once every 10 minutes to obtain a mixed filler dispersion. Separately, take 1.2 parts titanate coupling agent NDZ-105, add 10 parts deionized water, and stir for 10 minutes to prepare a coupling agent solution. Add 30 parts epoxy resin E44 to a mixing tank, stir at 1000 r / min for 5 minutes, then pour in the coupling agent solution, continue stirring for 20 minutes, then add 0.6 parts sodium lignosulfonate and 0.4 parts mineral oil defoamer, and stir for 10 minutes to obtain a resin base. Pour the mixed filler dispersion into the resin base, stir at 1800 r / min for 35 minutes, and finally add 2 parts nano silica, stir for 15 minutes, and filter through a 200-mesh filter to obtain a graphene thermally conductive slurry. S3. Adjust the gap between the coating rollers of the roller coater to 0.5mm and the coating speed to 1.5m / min. Lay the pretreated rock wood flat on the conveyor belt, coat it evenly with graphene thermal conductive slurry, and let it stand for 10 minutes after coating. S4. Place the coated rock wood in a 65℃ oven to dry for 35 minutes, remove it and ventilate to cool to room temperature, then put it back into the oven at 85℃ for 35 minutes, then cool it down to 55℃ and keep it for 20 minutes. The cooling rate is controlled at 5℃ / min. Remove it and let it cool naturally to room temperature. Use 240-grit sandpaper to lightly sand the surface of the heat-conducting layer, and wipe off the dust with a dry cloth to obtain the finished floor.

[0032] Example 3: Production of high-efficiency thermal insulation flooring based on graphene, the specific steps are as follows: S1. Take 0.6 parts of silane coupling agent KH-570 and add 17 parts of ethanol, stir for 10 minutes to prepare a waterproofing agent solution, apply it evenly to the degreased rock wood, apply 2 times, with an interval of 5 minutes; after application, place the rock wood in a ventilated place at 22℃ to dry for 35 minutes, and then use 180-grit sandpaper to sand the surface of the substrate to obtain pretreated rock wood. S2. Take 5 parts graphene, 2 parts micron-sized aluminum nitride, and 4 parts expanded vermiculite, add 22 parts deionized water, and ultrasonically disperse for 32 minutes, stirring once every 10 minutes to obtain a mixed filler dispersion. Separately, take 1 part titanate coupling agent NDZ-105, add 9 parts deionized water, and stir for 10 minutes to prepare a coupling agent solution. Add 27 parts epoxy resin E44 to a mixing tank, stir at 900 r / min for 5 minutes, then pour in the coupling agent solution, continue stirring for 17 minutes, then add 0.5 parts sodium lignosulfonate and 0.3 parts mineral oil defoamer, and stir for 10 minutes to obtain a resin base. Pour the mixed filler dispersion into the resin base, stir at 1650 r / min for 32 minutes. Finally, add 2 parts nano silica, stir for 15 minutes, and filter through a 200-mesh filter to obtain a graphene thermally conductive slurry. S3. Adjust the gap between the coating rollers of the roller coater to 0.4mm and the coating speed to 1.2m / min. Lay the pretreated rock wood flat on the conveyor belt, coat it evenly with graphene thermal conductive slurry, and let it stand for 7 minutes after coating. S4. Place the coated rock wood in a 62℃ oven to dry for 32 minutes, remove it and ventilate to cool to room temperature, then put it back into the oven at 82℃ for 32 minutes, then cool it down to 52℃ and keep it for 20 minutes. The cooling rate is controlled at 4℃ / min. Remove it and let it cool naturally to room temperature. Use 240-grit sandpaper to lightly sand the surface of the heat-conducting layer, wipe off the dust with a dry cloth, and you will get the finished floor.

[0033] Example 4: Preparation of modified graphene. The specific preparation steps are as follows: A1. Take 10g of graphene powder and add 150mL of 31% hydrochloric acid. Stir at 200r / min for 20min at room temperature, then heat to 45℃ and continue stirring for 1.5h. After the reaction, slowly add 300mL of deionized water to dilute, stir for 10min, let stand for 30min, pour off the supernatant, keep the lower graphene slurry, add 6g of industrial grade urea to the slurry, stir and heat to 60℃, stir at 300r / min for 2h. After the reaction, filter, wash the filter cake with deionized water until pH=5, and dry in an 80℃ oven for 3h to obtain oxidized intercalated graphene. A2. Add 120 mL of deionized water to the oxide-intercalated graphene and sonicate for 20 min. Add 4 g of corn starch, stir and heat to 70 °C, add hydrochloric acid to adjust pH=3, and stir at 300 r / min for 3 h. Add 2 g of micron-sized aluminum nitride to the system and continue stirring for 1 h. After the reaction, filter, wash the filter cake twice with deionized water, and dry it in a 75 °C oven for 2.5 h to obtain starch-aluminum nitride modified graphene. A3. Add starch-aluminum nitride modified graphene to 80 mL of 95% ethanol and stir to disperse for 10 min. Then add 3 g of potassium dihydrogen phosphate, heat to 55 °C, and stir at 250 r / min for 2 h. After filtration, wash the filter cake once with ethanol and dry at 70 °C for 1 h. Separately, take 8 g of epoxy resin E44, add 20 mL of deionized water, stir to dissolve, add 1 g of modified amine curing agent, and stir for 10 min to obtain a prepolymer. Add the dried graphene powder to the prepolymer, heat to 65 °C, and stir at 300 r / min for 3 h. After the reaction, filter and dry the filter cake in an oven at 85 °C for 3 h to obtain the final modified graphene.

[0034] Example 5: Preparation of modified graphene. The specific preparation steps are as follows: A1. Take 15g of graphene powder and add 200mL of 31% hydrochloric acid. Stir at 250r / min for 25min at room temperature, then heat to 50℃ and continue stirring for 2h. After the reaction, slowly add 350mL of deionized water to dilute. Stir for 10min and let stand for 30min. Pour off the supernatant and keep the lower graphene slurry. Add 9g of industrial-grade urea to the slurry, stir and heat to 65℃, and stir at 350r / min for 2.5h. After the reaction, filter. Wash the filter cake with deionized water until pH=6, and dry in an 85℃ oven for 3.5h to obtain oxidized intercalated graphene. A2. Add 150 mL of deionized water to the oxide-intercalated graphene and sonicate for 25 min. Add 6 g of corn starch, stir and heat to 75 °C, add hydrochloric acid to adjust pH=4, and stir at 350 r / min for 3.5 h. Add 3 g of micron-sized aluminum nitride to the system and continue stirring for 1.5 h. After the reaction, filter, wash the filter cake twice with deionized water, and dry it in an 80 °C oven for 3 h to obtain starch-aluminum nitride modified graphene. A3. Add starch-aluminum nitride modified graphene to 100 mL of 95% ethanol and stir to disperse for 10 min. Then add 5 g of potassium dihydrogen phosphate, heat to 60 °C, and stir at 300 r / min for 2.5 h. After filtration, wash the filter cake once with ethanol and dry at 70 °C for 1 h. Separately, take 10 g of epoxy resin E44, add 30 mL of deionized water, stir to dissolve, add 2 g of modified amine curing agent, and stir for 10 min to obtain a prepolymer. Add the dried graphene powder to the prepolymer, heat to 70 °C, and stir at 300 r / min for 3.5 h. After the reaction, filter and dry the filter cake in an oven at 90 °C for 3 h to obtain the final modified graphene.

[0035] Example 6: Preparation of modified expanded vermiculite. The specific preparation steps are as follows: B1. Take 20g of expanded vermiculite and add it to 200mL of 10% sodium hydroxide solution. Stir at 150r / min for 1h at room temperature. After filtration, wash with deionized water until pH=7 and dry in an oven at 100℃ for 2h. Take 5g of sodium silicate and add it to 80mL of deionized water. Stir to dissolve and obtain sodium silicate solution. Add the dried vermiculite to the solution and stir at room temperature for 30min. Remove the vermiculite, drain it, and dry it in an oven at 110℃ for 1.5h to obtain sodium silicate coated vermiculite. B2. Take sodium silicate-coated vermiculite and add it to 150 mL of deionized water. Stir and disperse for 5 min. Add 4 g of polyvinyl alcohol, heat to 80 °C, stir at 200 r / min for 2 h. Then add 1 g of maleic anhydride to the system, continue to heat to 90 °C, stir for 2 h. After completion, filter and dry in an oven at 95 °C for 2 h to obtain polyvinyl alcohol-maleic anhydride modified expanded vermiculite. B3. Add 150 mL of deionized water to polyvinyl alcohol-maleic anhydride modified expanded vermiculite and stir at 150 r / min for 5 min at room temperature to form a stable suspension. Then add 8 g of 30% solid content water-based paraffin emulsion and increase the stirring speed to 200 r / min. Stir at room temperature for 30 min. Then add 2 g of zinc borate powder and continue stirring at 200 r / min for 1 h. After stirring, filter the mixture. Wash the filter cake once with deionized water and dry it in an 80℃ oven for 1.5 h to obtain modified expanded vermiculite.

[0036] Example 7: Preparation of modified expanded vermiculite. The specific preparation steps are as follows: B1. Take 30g of expanded vermiculite and add it to 250mL of 10% sodium hydroxide solution. Stir at 200r / min for 1.5h at room temperature. After filtration, wash with deionized water until pH=8 and dry in an oven at 105℃ for 2h. Take 7g of sodium silicate and add it to 100mL of deionized water. Stir to dissolve and obtain sodium silicate solution. Add the dried vermiculite to the solution and stir at room temperature for 40min. Take out the vermiculite, drain it, and dry it in an oven at 120℃ for 2h to obtain sodium silicate coated vermiculite. B2. Take sodium silicate-coated vermiculite and add it to 200 mL of deionized water. Stir and disperse for 5 min. Add 6 g of polyvinyl alcohol, heat to 85 °C, and stir at 250 r / min for 2.5 h. Then add 2 g of maleic anhydride to the system, continue to heat to 95 °C, and stir for 2.5 h. After completion, filter and dry in an oven at 100 °C for 2 h to obtain polyvinyl alcohol-maleic anhydride modified expanded vermiculite. B3. Add polyvinyl alcohol-maleic anhydride modified expanded vermiculite to 200 mL of deionized water, stir at 200 r / min for 5 min at room temperature to form a stable suspension, then add 12 g of 30% solid content water-based paraffin emulsion, increase the stirring speed to 250 r / min, stir at room temperature for 40 min, then add 3 g of zinc borate powder, and continue stirring at 250 r / min for 1.5 h. After stirring, filter, wash the filter cake once with deionized water, and dry it in an 85℃ oven for 2 h to obtain modified expanded vermiculite.

[0037] Comparative Example 1: Production of high-efficiency thermal insulation flooring based on graphene, the specific steps are as follows: The remaining steps remain the same, except that the graphene in Example 3 is replaced with the modified graphene prepared in Example 4 to obtain a high-efficiency thermal insulation floor based on graphene.

[0038] Comparative Example 2: Production of high-efficiency thermal insulation flooring based on graphene, the specific steps are as follows: The remaining steps remain the same, except that the expanded vermiculite in Example 3 is replaced with the modified expanded vermiculite prepared in Example 7 to obtain a high-efficiency thermal insulation floor based on graphene.

[0039] Comparative Example 3: Production of high-efficiency thermal insulation flooring based on graphene, the specific steps are as follows: The remaining steps remain unchanged, except that the graphene in Example 3 is replaced with the modified graphene prepared in Example 4, and the expanded vermiculite is replaced with the modified expanded vermiculite prepared in Example 7, to obtain a high-efficiency thermal insulation floor based on graphene.

[0040] Performance testing

[0041]

[0042] According to performance tests, Examples 1-3 without modified materials had a thermal conductivity of [missing value]. The flexural strength is 16.2-17.2 MPa, water absorption is 2.8%-3.2%, thermal conductivity increases by 7.1%-8.2% after thermal cycling, wear resistance is 420-450 revolutions, and thermal conductivity decreases by 8.2%-9.5% during aging. Comparative examples 1-3, using modified graphene and modified expanded vermiculite, exhibit superior performance in all aspects, with Comparative Example 3, combining the two modified materials, showing the lowest thermal conductivity. With a flexural strength of up to 19.3 MPa and a water absorption rate of down to 1.8%, the thermal conductivity increases by only 3.2% after thermal cycling. It is wear-resistant for 560 revolutions and its thermal conductivity changes to 4.1% after aging. The combined use of dual modified materials can significantly improve the overall performance of the flooring.

[0043] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A high-efficiency thermal insulation floor based on graphene, characterized in that: This high-efficiency thermal insulation floor is made of rockwood as the base material and coated with graphene thermal conductive paste. The graphene thermal conductive paste contains the following raw materials in parts by weight: 4-6 parts modified graphene, 25-30 parts epoxy resin E44, 2-3 parts micron-sized aluminum nitride, 3-5 parts modified expanded vermiculite, 0.8-1.2 parts titanate coupling agent NDZ-105, 0.3-0.6 parts sodium lignosulfonate, 0.2-0.4 parts mineral oil defoamer, 28-35 parts deionized water, 15-20 parts ethanol, 0.5-0.8 parts silane coupling agent KH-570, and 1-2 parts nano silica.

2. The high-efficiency thermal insulation flooring based on graphene according to claim 1, characterized in that: The modified graphene powder is prepared using the following specific steps: A1. Take graphene powder and add 31% hydrochloric acid by mass. Stir at 200-250 r / min for 20-25 min at room temperature, then heat to 45-50℃ and continue stirring for 1.5-2 h. After the reaction, slowly add deionized water to dilute, stir for 10 min, let stand for 30 min, pour off the supernatant, keep the lower graphene slurry, add industrial grade urea to the slurry, stir and heat to 60-65℃, stir at 300-350 r / min for 2-2.5 h. After the reaction, filter, wash the filter cake with deionized water until pH=5-6, and dry in an oven at 80-85℃ for 3-3.5 h to obtain oxidized intercalated graphene. A2. Add oxide-intercalated graphene to deionized water and ultrasonically disperse for 20-25 min; add corn starch, stir and heat to 70-75℃, add hydrochloric acid dropwise to adjust pH=3-4, and stir at 300-350 r / min for 3-3.5 h; add micron-sized aluminum nitride to the system and continue stirring for 1-1.5 h; after the reaction, filter, wash the filter cake twice with deionized water, and dry it in an oven at 75-80℃ for 2.5-3 h to obtain starch-aluminum nitride modified graphene; A3. Add starch-aluminum nitride modified graphene to 95% ethanol and stir to disperse for 10 min. Then add potassium dihydrogen phosphate, heat to 55-60℃, and stir at 250-300 r / min for 2-2.5 h. After filtration, wash the filter cake once with ethanol and dry at 70℃ for 1 h. Separately, take epoxy resin E44, add deionized water, stir to dissolve, add modified amine curing agent, and stir for 10 min to obtain a prepolymer. Add the dried graphene powder to the prepolymer, heat to 65-70℃, and stir at 300 r / min for 3-3.5 h. After the reaction, filter and dry the filter cake in an oven at 85-90℃ for 3 h to obtain the final modified graphene.

3. The high-efficiency thermal insulation flooring based on graphene according to claim 2, characterized in that: The ratio of graphene powder, hydrochloric acid, deionized water, and industrial-grade urea in A1 is 10-15g: 150-200mL: 300-350mL: 6-9g; The ratio of deionized water, corn starch, and micron-sized aluminum nitride in A2 is 120-150 mL: 4-6 g: 2-3 g; The ratio of ethanol, potassium dihydrogen phosphate, epoxy resin E44, deionized water, and modified amine curing agent in A3 is 80-100mL: 3-5g: 8-10g: 20-30mL: 1-2g.

4. The high-efficiency thermal insulation flooring based on graphene according to claim 2, characterized in that: The modified amine curing agent in A3 is prepared by the following method: 20-30g of ethylenediamine is added to 5-8g of propylene oxide and stirred at 200-250r / min for 30-40min, during which the temperature is controlled not to exceed 40℃. Then, 3-5g of xylene is added and stirring is continued for 15-20min. Then, glacial acetic acid is added dropwise to adjust the pH to 7. After stirring for 10min, the mixture is allowed to stand for 20min to remove a small amount of layered impurities, thus obtaining the modified amine curing agent.

5. The high-efficiency thermal insulation flooring based on graphene according to claim 1, characterized in that: The modified expanded vermiculite is prepared using the following specific steps: B1. Take expanded vermiculite and add it to a 10% sodium hydroxide solution. Stir at 150-200 r / min for 1-1.5 h at room temperature. After filtration, wash with deionized water until pH=7-8, and dry in an oven at 100-105℃ for 2 h. Take sodium silicate, add it to deionized water, stir to dissolve and obtain sodium silicate solution. Add the dried vermiculite to the solution, stir at room temperature for 30-40 min, remove the vermiculite, drain it and dry in an oven at 110-120℃ for 1.5-2 h to obtain sodium silicate coated vermiculite. B2. Take sodium silicate-coated vermiculite, add it to deionized water, stir and disperse for 5 min, add polyvinyl alcohol, heat to 80-85℃, stir at 200-250 r / min for 2-2.5 h, then add maleic anhydride to the system, continue to heat to 90-95℃, stir for 2-2.5 h, filter after completion, and dry in an oven at 95-100℃ for 2 h to obtain polyvinyl alcohol-maleic anhydride modified expanded vermiculite; B3. Add polyvinyl alcohol-maleic anhydride modified expanded vermiculite to deionized water and stir at 150-200 r / min for 5 min at room temperature to form a stable suspension. Then add 30% solid content water-based paraffin emulsion and increase the stirring speed to 200-250 r / min. Stir at room temperature for 30-40 min. Then add zinc borate powder and continue stirring at 200-250 r / min for 1-1.5 h. After stirring, filter and wash the filter cake once with deionized water. Dry it in an oven at 80-85℃ for 1.5-2 h to obtain modified expanded vermiculite.

6. The high-efficiency thermal insulation flooring based on graphene according to claim 5, characterized in that: The ratio of expanded vermiculite, sodium hydroxide solution, sodium silicate, and deionized water in B1 is 20-30g: 200-250mL: 5-7g: 80-100mL; The ratio of deionized water, polyvinyl alcohol, and maleic anhydride in B2 is 150-200mL: 4-6g: 1-2g; The ratio of deionized water, aqueous paraffin emulsion, and zinc borate powder in B3 is 150-200mL: 8-12g: 2-3g.

7. A production process for high-efficiency thermal insulation flooring based on graphene, characterized in that: Specifically, it includes the following steps: S1. Take silane coupling agent KH-570 and add it to ethanol, stir for 10 minutes to prepare a waterproofing agent solution, apply it evenly to the degreased rock wood, apply 2 times, with an interval of 5 minutes; after application, place the rock wood in a ventilated place at 20-25℃ to dry for 30-40 minutes, and then use 180-grit sandpaper to sand the surface of the substrate to obtain pretreated rock wood. S2. Add modified graphene, micron-sized aluminum nitride, and modified expanded vermiculite to deionized water and ultrasonically disperse for 30-35 minutes, stirring once every 10 minutes to obtain a mixed filler dispersion. Separately, add titanate coupling agent NDZ-105 to deionized water and stir for 10 minutes to prepare a coupling agent solution. Add epoxy resin E44 to a mixing tank and stir at 800-1000 r / min for 5 minutes, then pour in the coupling agent solution and continue stirring for 15-20 minutes. Add sodium lignosulfonate and mineral oil defoamer and stir for 10 minutes to obtain a resin base. Pour the mixed filler dispersion into the resin base and stir at 1500-1800 r / min for 30-35 minutes. Finally, add nano-silica and stir for 15 minutes. After filtration through a 200-mesh filter, obtain a graphene thermally conductive slurry. S3. Adjust the gap between the coating rollers of the roller coater to 0.3-0.5mm, and the coating speed to 1-1.5m / min. Lay the pretreated rock wood flat on the conveyor belt, coat it evenly with graphene thermal conductive slurry, and let it stand for 5-10 minutes after coating. S4. Place the coated rock wood in an oven at 60-65℃ and dry for 30-35 minutes. Remove it and allow it to cool to room temperature. Then place it back in the oven at 80-85℃ and keep it warm for 30-35 minutes. After that, lower the temperature to 50-55℃ and keep it warm for 20 minutes. Remove it and allow it to cool naturally to room temperature. Lightly sand the surface of the heat-conducting layer with 240-grit sandpaper and wipe off the dust with a dry cloth to obtain the finished flooring.

8. The production process of a graphene-based high-efficiency thermal insulation floor according to claim 7, characterized in that: The viscosity of the graphene thermal conductive slurry at 25°C is: Furthermore, the viscosity can be finely adjusted by changing the amount of ethanol used; for every 1 part increase in ethanol, the viscosity of the slurry can be reduced. .

9. The production process of a graphene-based high-efficiency thermal insulation floor according to claim 7, characterized in that: The density of the rock wood is 0.65-0.75 g / cm³. 3 The moisture content is ≤12%, and the rock wood is degreased by hot air at 85℃ for 1.5h before being used as a substrate. After degreasing, it is naturally cooled to room temperature before being used in the subsequent coating process. In the cooling process of S4, the cooling rate is controlled at 3-5℃ / min.

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