Preparation process of water-based graphene inorganic zero-aldehyde rare earth heat insulation coating

Abstract

The application belongs to the technical field of coating preparation, and particularly relates to a preparation process of a water-based graphene inorganic zero-aldehyde rare earth heat insulation coating, and the specific steps of the preparation process are as follows: microbead filler pretreatment, preparation of a water-based inorganic zero-aldehyde base material, preparation of a water-soluble graphene dispersion liquid, blending and dispersion of main fillers and the inorganic base material, incorporation of the graphene dispersion liquid, and preparation of a finished product by adding functional additives; the main raw materials for preparing the heat insulation coating in the application are ceramic particle microbeads and silicon microbeads, the particle size of the ceramic particle microbeads and the silicon microbeads is 60-70 mu m, the microbeads are closed hollow and vacuum structures inside, the specific gravity of the coating layer is effectively reduced, the porosity of the coating layer is increased, and solid conduction is reduced; the internal space of the microbeads is a closed structure, and the inner diameter is very small, so that convection conduction can be limited, the microbeads are vacuum, and convection heat transfer and conduction heat transfer of the gas phase in the microbeads can be further limited.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, specifically to a preparation process for an aqueous graphene inorganic zero-aldehyde rare earth thermal insulation coating. Background Technology

[0002] With the escalating global energy crisis and the continued advancement of "dual carbon" goals, energy conservation and emission reduction in the building and industrial sectors have become core development directions. Among these, thermal insulation coatings, as a key technology for energy conservation in building envelopes, can effectively block solar radiation and heat transfer, reduce air conditioning and insulation energy consumption, and extend the service life of equipment and substrates. They are widely used in building exterior walls, steel structures, chemical pipelines, and new energy equipment.

[0003] However, existing heat insulation coatings suffer from poor thermal insulation performance, low adhesion strength, short service life, and reduced decorative properties due to the poor characteristics of the main fillers selected during their preparation.

[0004] To address these issues, a preparation process for an aqueous graphene inorganic zero-aldehyde rare earth thermal insulation coating is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a preparation process for an aqueous graphene inorganic zero-aldehyde rare earth thermal insulation coating to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a preparation process for an aqueous graphene inorganic zero-aldehyde rare-earth thermal insulation coating, the specific steps of which are as follows: Step 1: Pretreatment of microsphere filler: Weigh ceramic microspheres and silicon microspheres as the main heat insulation filler, control the particle size of ceramic microspheres and silicon microspheres to be 60-70μm, and the internal structure of the microspheres to be closed hollow and vacuum structure; put the ceramic microspheres and silicon microspheres into the graded purification device for air separation to remove impurities and sieve to remove broken particles, ensuring that the microsphere cavity is intact and undamaged. Step 2: Preparation of water-based inorganic zero-formaldehyde matrix: Add deionized water, inorganic silica sol, inorganic silicate binder and rare earth inorganic additives to a closed reaction vessel, and disperse for 15-20 minutes at room temperature and low speed stirring at 300-450 r / min to form a transparent and uniform water-based inorganic zero-formaldehyde matrix. Step 3: Preparation of water-soluble graphene dispersion: Add water-soluble graphene to deionized water, along with an inorganic dispersant, and disperse it for 25-35 minutes at 1800-2200 r / min using a high-speed shear disperser to obtain a non-agglomerated, highly stable graphene dispersion. Step 4: Blending and dispersing the main filler and inorganic matrix: Slowly add the hollow vacuum composite microspheres pretreated in Step 1 to the water-based inorganic matrix prepared in Step 2, and keep the stirring speed at 500-800 r / min for 30-40 min. Step 5: Incorporation of graphene dispersion: Slowly add the water-soluble graphene dispersion prepared in step 3 to the above-mentioned mixing system, control the stirring speed of the stirring device to 600-900 r / min, and continue stirring for 20-30 min to make the graphene evenly distributed on the surface of the microspheres and in the gap between the base material. Step 6: Adding functional additives: Add inorganic acid and alkali resistant agent, UV resistant agent, inorganic toughening agent, and moisture resistant agent in sequence, and stir at low speed for 10-15 minutes until completely uniform; Step 7: Preparation of finished product: Filter the mixed slurry through an 80-100 mesh screen to remove impurities, and then let it stand for 25-35 minutes under a negative pressure of -0.06 to -0.08 MPa to degas, so as to obtain a uniform and stable suspended heat insulation coating.

[0007] Preferably, in step one, the selected ceramic microspheres and silicon microspheres account for 70%-75% of the total mass of the coating, and the ceramic microspheres and silicon microspheres are mixed in a mass ratio of 1:1.

[0008] Preferably, in step two, when preparing the water-based inorganic zero-formaldehyde base material, 42-48 parts of deionized water, 28-32 parts of inorganic silica sol, 15-18 parts of inorganic silicate binder, and 2.5-4.5 parts of rare earth inorganic additives are selected.

[0009] Preferably, in step three, when preparing the water-soluble graphene dispersion, 1-3 parts of water-soluble graphene, 0.4-0.8 parts of inorganic dispersant, and 95-100 parts of deionized water are selected.

[0010] Preferably, in step six, the added inorganic acid and alkali resistant agent is 0.4-0.8 parts, the UV resistant agent is 0.3-0.6 parts, the inorganic toughening agent is 0.5-0.9 parts, and the moisture-proof agent is 0.2-0.5 parts.

[0011] Preferably, in step six, the inorganic acid and alkali resistant agent is specifically a nano-silane modified inorganic corrosion resistant agent, the UV resistant agent is specifically a nano-cerium oxide rare earth UV shielding agent, the inorganic toughening agent is specifically a nano-silica elastic toughening agent, and the moisture-proof agent is specifically an inorganic siloxane hydrophobic moisture-proof agent.

[0012] Preferably, after the heat insulation coating is prepared, the finished product is packaged in a plastic bucket and stored in a dry, light-proof environment at a temperature of 5-15℃.

[0013] Compared with the prior art, the beneficial effects of the present invention are: The thermal insulation coating in this application is mainly prepared using ceramic microspheres and silicon microspheres as raw materials. The ceramic microspheres and silicon microspheres have a particle size of 60-70μm. The internal structure of the microspheres is a closed hollow and vacuum structure, which effectively reduces the specific gravity of the coating layer and increases the porosity of the coating layer, thereby reducing solid conduction. The internal pores of the microspheres are closed structures with very small inner diameters, which can limit convection conduction. The vacuum inside the microspheres can further limit convective heat transfer and eliminate conduction heat transfer of the gas phase inside the microspheres. The internal cavity of the microspheres forms a large number of reflective and radiative surfaces, thereby reducing radiative heat transfer. After the thermal insulation coating dries, the internal structure is a closed microporous structure, which can seamlessly cover the surface of thermal equipment, eliminating the "thermal bridge" heat loss caused by the seams or fibrous structure of other types of thermal insulation materials. It also has good moisture resistance, which helps to reduce the impact of moisture on the thermal conductivity. Attached Figure Description

[0014] Figure 1 This is a flowchart illustrating the preparation process of this heat-insulating coating. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0016] Example:

[0017] Please see Figure 1 The present invention provides a technical solution: A preparation process for an aqueous graphene inorganic zero-aldehyde rare-earth thermal insulation coating, the specific steps of which are as follows: Step 1: Microsphere Filler Pretreatment: Weigh ceramic microspheres and silicon microspheres as the main thermal insulation filler, controlling the particle size of the ceramic and silicon microspheres to be 60-70μm, with the internal structure of the microspheres being a closed hollow and vacuum structure; put the ceramic and silicon microspheres into a graded purification device for air classification to remove impurities and sieving to remove broken particles, ensuring that the microsphere cavities are intact and undamaged; selecting ceramic and silicon microspheres with a particle size of 60-70μm and a closed hollow and vacuum structure ensures that the coating has the basis of low thermal conductivity, high reflectivity, and low heat transfer. By air classification to remove impurities and sieving to remove broken particles, the integrity of the microsphere cavities is ensured and the broken microspheres are not damaged, avoiding the reduction of thermal insulation effect by broken microspheres. The proportion of the main filler is controlled to 70%-75%, providing the main thermal insulation support for the coating and ensuring the stable achievement of low thermal conductivity; Step 2: Preparation of Water-Based Inorganic Zero-Formaldehyde Base Material: In a sealed reactor, add deionized water, inorganic silica sol, inorganic silicate binder, and rare earth inorganic additives. Disperse the mixture for 15-20 minutes at room temperature and low speed stirring (300-450 rpm) to form a transparent and uniform water-based inorganic zero-formaldehyde matrix. The system contains no formaldehyde, VOCs, organic solvents, or toxic additives; it is non-toxic and odorless, achieving true zero-formaldehyde environmental protection. Using deionized water, inorganic silica sol, inorganic silicate binder, and rare earth inorganic additives forms a completely inorganic, zero-formaldehyde, zero-VOC, non-toxic, and odorless film-forming matrix, achieving environmental safety. Low-speed stirring at room temperature ensures uniform dispersion of all components, forming a transparent, uniform, and highly stable inorganic matrix, guaranteeing good compatibility with microspheres and graphene. The rare earth inorganic additives provide infrared reflection, enhanced heat insulation, and improved weather resistance, enhancing the overall performance of the coating. Step 3: Preparation of water-soluble graphene dispersion: Water-soluble graphene is added to deionized water, along with an inorganic dispersant, and dispersed for 25-35 minutes at 1800-2200 r / min using a high-speed shear disperser to obtain a non-agglomerated, highly stable graphene dispersion. Graphene is used to improve the adhesion strength, cohesion, ductility, and heat insulation uniformity of the coating, solving the problems of low adhesion and easy cracking of traditional coatings. Pre-dispersing graphene into a non-agglomerated, highly stable dispersion avoids agglomeration and sedimentation caused by direct addition. The inorganic dispersant ensures uniform dispersion and long-term stability of graphene. Graphene is used to subsequently enhance the adhesion, cohesion, ductility, and structural strength of the coating, solving the problems of easy cracking and low adhesion of traditional coatings. Step 4: Blending and Dispersing the Main Filler with the Inorganic Base Material: Slowly add the pretreated hollow vacuum composite microspheres from Step 1 to the aqueous inorganic base material prepared in Step 2, maintaining a stirring speed of 500-800 r / min and stirring for 30-40 min to ensure the microspheres are uniformly suspended, do not settle, and do not agglomerate; uniformly disperse the hollow vacuum microspheres in the inorganic base material, ensuring the microspheres are uniformly suspended, do not settle, and do not agglomerate. Medium-speed stirring ensures the microspheres remain intact and do not break, preserving the hollow vacuum structure and constructing a continuous porous skeleton for the coating, laying the foundation for the formation of a closed microporous structure; Step 5: Incorporation of Graphene Dispersion: Slowly add the water-soluble graphene dispersion prepared in Step 3 to the above-mentioned mixing system, controlling the stirring speed of the stirring device to 600-900 r / min, and continue stirring for 20-30 min. This allows the graphene to be evenly distributed on the surface of the microspheres and in the gaps between the substrate, strengthening the bonding force between the microspheres and the substrate, significantly improving the coating adhesion strength and thermal stability, and increasing the infrared reflectivity of the coating to approximately 68%, reflecting heat back to the heat source and further reducing heat loss. The uniform distribution of graphene on the surface of the microspheres and in the gaps between the substrate forms an interface-enhanced structure, strengthening the bonding force between the microspheres and the inorganic substrate, improving the overall integrity, adhesion, and ductility of the coating, and synergistically increasing the infrared reflectivity to approximately 68% with the rare earth components, reflecting heat, reducing heat loss, improving the uniformity of the coating structure, and ensuring that the thermal conductivity is stable at ≤0.034 W / (m・K). Step 6: Adding functional additives: Add inorganic acid and alkali resistant agent, UV resistant agent, inorganic toughening agent, and moisture resistant agent in sequence, and stir at low speed for 10-15 minutes until completely uniform; The control system enables the coating to achieve the following: thermal conductivity ≤0.034 W / (m・K) (lower than still air); elongation >30%; bonding strength with cement ≥0.5MPa; bonding strength with steel plate ≥0.38MPa; solid content >65%; after the coating is formed, it has a continuous closed microporous structure, with no seams, no thermal bridges, and excellent moisture resistance, avoiding thermal bridge losses of traditional materials; Step 7: Finished Product Preparation: Filter the mixed slurry through an 80-100 mesh screen to remove impurities, then allow it to stand for 25-35 minutes under a negative pressure of -0.06 to -0.08 MPa to degas, obtaining a uniform and stable suspended thermal insulation coating. Filtering with an 80-100 mesh screen removes large particles and impurities, ensuring a fine and uniform coating; negative pressure degassing eliminates internal bubbles, preventing porosity, heat leakage, and reduced strength after film formation, ultimately forming a uniform and stable suspended aqueous graphene inorganic zero-aldehyde rare earth thermal insulation coating.

[0018] In step one, the selected ceramic microspheres and silicon microspheres account for 70%-75% of the total mass of the coating, and the ceramic microspheres and silicon microspheres are mixed in a mass ratio of 1:1 to ensure sufficient heat insulation filler, low thermal conductivity, optimal heat insulation effect, and take into account both flowability and film formation.

[0019] In step two, when preparing the water-based inorganic zero-formaldehyde base material, 42-48 parts of deionized water, 28-32 parts of inorganic silica sol, 15-18 parts of inorganic silicate binder, and 2.5-4.5 parts of rare earth inorganic additives are selected to ensure film-forming properties, adhesion, zero-formaldehyde environmental protection, and efficient infrared reflection of rare earth elements.

[0020] In step three, when preparing the water-soluble graphene dispersion, 1-3 parts of water-soluble graphene, 0.4-0.8 parts of inorganic dispersant, and 95-100 parts of deionized water are selected. This ensures optimal graphene dispersion without excessive amounts or agglomeration, resulting in the most stable enhancement effect.

[0021] In step six, the added inorganic acid and alkali resistant agent is 0.4-0.8 parts, the UV resistant agent is 0.3-0.6 parts, the inorganic toughening agent is 0.5-0.9 parts, and the moisture-proof agent is 0.2-0.5 parts. The dosage is moderate and efficient, does not affect the main filler system, and achieves corrosion resistance, UV resistance, toughening, and moisture-proofing.

[0022] In step six, the inorganic acid and alkali resistant agent is specifically a nano-silane modified inorganic corrosion resistant agent, the UV resistant additive is specifically a nano-cerium oxide rare earth UV shielding agent, the inorganic toughening agent is specifically a nano-silica elastic toughening agent, and the moisture-proof agent is specifically an inorganic siloxane hydrophobic moisture-proof agent. The nano-silane modified inorganic corrosion resistant agent improves the coating's acid, alkali, and corrosion resistance, extending its service life; the nano-cerium oxide rare earth UV shielding agent resists ultraviolet rays, prevents aging, and enhances weather resistance; the nano-silica elastic toughening agent improves the coating's ductility by >30%, making it less prone to cracking and peeling; and the inorganic siloxane hydrophobic moisture-proof agent improves moisture-proof performance, prevents moisture from increasing the thermal conductivity, and maintains thermal insulation stability. This results in a coating with high bonding strength, a solid content >65%, no thermal bridges, and a closed microporous structure.

[0023] After the heat insulation coating is prepared, the finished product is packaged in plastic buckets and stored in a dry and dark environment at a temperature of 5-15℃ to ensure that the coating does not separate, deteriorate, or gel, and has stable storage and a long shelf life.

[0024] Key characteristics of this heat-insulating coating: 1. Excellent thermal insulation effect: Its overall thermal conductivity is less than that of still air; 2. Extensibility: It has excellent extensibility, with an elongation rate greater than 30%; 3. Corrosion resistance: The fillers in the coating have high acid and alkali resistance, as well as excellent UV resistance. 4. Adhesion: Tested adhesion strength with cement reaches 0.5 MPa, and with steel plate reaches 0.38 MPa. It exhibits good adhesion strength on most clean, dry surfaces. 5. Environmental friendliness: It does not contain harmful volatile organic compounds, the product is non-toxic and odorless, and is water-soluble; it will not produce harmful waste or gases during use. 6. Workability: It can be applied using either ordinary troweling or machine spraying; 7. Applicability: Suitable for interior wall insulation in all buildings; 8. Long service life: 15-20 years; good decorative effect; 9. Usage and dosage: The water-based graphene inorganic zero-formaldehyde heat insulation coating is packaged in liquid form (suspension) with a solid content of more than 65%. It can be diluted with about 5% water according to construction needs. It should be thoroughly mixed with a hand-held electric mixer before spraying. The total thickness of the spray is between 1.5 and 2 mm.

[0025] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0026] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A preparation process for an aqueous graphene inorganic zero-aldehyde rare-earth thermal insulation coating, characterized in that, The specific steps of this preparation process are as follows: Step 1: Pretreatment of microsphere filler: Weigh ceramic microspheres and silicon microspheres as the main heat insulation filler, control the particle size of ceramic microspheres and silicon microspheres to be 60-70μm, and the internal structure of the microspheres to be closed hollow and vacuum structure; put the ceramic microspheres and silicon microspheres into the graded purification device for air separation to remove impurities and sieve to remove broken particles, ensuring that the microsphere cavity is intact and undamaged. Step 2: Preparation of water-based inorganic zero-formaldehyde matrix: Add deionized water, inorganic silica sol, inorganic silicate binder and rare earth inorganic additives to a closed reaction vessel, and disperse for 15-20 minutes at room temperature and low speed stirring at 300-450 r / min to form a transparent and uniform water-based inorganic zero-formaldehyde matrix. Step 3: Preparation of water-soluble graphene dispersion: Add water-soluble graphene to deionized water, along with an inorganic dispersant, and disperse it for 25-35 minutes at 1800-2200 r / min using a high-speed shear disperser to obtain a non-agglomerated, highly stable graphene dispersion. Step 4: Blending and dispersing the main filler and inorganic matrix: Slowly add the hollow vacuum composite microspheres pretreated in Step 1 to the water-based inorganic matrix prepared in Step 2, and keep the stirring speed at 500-800 r / min for 30-40 min. Step 5: Incorporation of graphene dispersion: Slowly add the water-soluble graphene dispersion prepared in step 3 to the above-mentioned mixing system, control the stirring speed of the stirring device to 600-900 r / min, and continue stirring for 20-30 min to make the graphene evenly distributed on the surface of the microspheres and in the gap between the base material. Step 6: Adding functional additives: Add inorganic acid and alkali resistant agent, UV resistant agent, inorganic toughening agent, and moisture resistant agent in sequence, and stir at low speed for 10-15 minutes until completely uniform; Step 7: Preparation of finished product: Filter the mixed slurry through an 80-100 mesh screen to remove impurities, and then let it stand for 25-35 minutes under a negative pressure of -0.06 to -0.08 MPa to degas, so as to obtain a uniform and stable suspended heat insulation coating.

2. The preparation process of the water-based graphene inorganic zero-aldehyde rare earth thermal insulation coating according to claim 1, characterized in that: In step one, the selected ceramic microspheres and silicon microspheres account for 70%-75% of the total mass of the coating, and the ceramic microspheres and silicon microspheres are mixed in a mass ratio of 1:

1.

3. The preparation process of an aqueous graphene inorganic zero-aldehyde rare-earth thermal insulation coating according to claim 1, characterized in that: In step two, when preparing the water-based inorganic zero-formaldehyde base material, 42-48 parts of deionized water, 28-32 parts of inorganic silica sol, 15-18 parts of inorganic silicate binder, and 2.5-4.5 parts of rare earth inorganic additives are selected.

4. The preparation process of an aqueous graphene inorganic zero-aldehyde rare earth thermal insulation coating according to claim 1, characterized in that: In step three, when preparing the water-soluble graphene dispersion, 1-3 parts of water-soluble graphene, 0.4-0.8 parts of inorganic dispersant, and 95-100 parts of deionized water are selected.

5. The preparation process of an aqueous graphene inorganic zero-aldehyde rare-earth thermal insulation coating according to claim 1, characterized in that: In step six, the added inorganic acid and alkali resistant agent is 0.4-0.8 parts, the UV resistant agent is 0.3-0.6 parts, the inorganic toughening agent is 0.5-0.9 parts, and the moisture-proof agent is 0.2-0.5 parts.

6. The preparation process of an aqueous graphene inorganic zero-aldehyde rare-earth thermal insulation coating according to claim 1, characterized in that: In step six, the inorganic acid and alkali resistant agent is specifically a nano-silane modified inorganic corrosion resistant agent, the UV resistant agent is specifically a nano-cerium oxide rare earth UV shielding agent, the inorganic toughening agent is specifically a nano-silica elastic toughening agent, and the moisture-proof agent is specifically an inorganic siloxane hydrophobic moisture-proof agent.

7. The preparation process of an aqueous graphene inorganic zero-aldehyde rare earth thermal insulation coating according to claim 1, characterized in that: After the heat insulation coating is prepared, the finished product is packaged in plastic buckets and stored in a dry, light-proof environment at a temperature of 5-15℃.

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