A silica aerogel water-based heat-insulating and heat-preserving coating and its preparation method

Abstract

The present invention relates to the technical field of coatings, and particularly relates to a SiO 2 aerogel water-based heat-insulating and heat-preserving coating and a preparation method thereof. By weight, the components of the coating include: 7-15 parts of water, 10-15 parts of hollow glass microspheres, SiO 2 aerogel slurry 40-50 parts, 0.1-0.3 part of a first neutralizing agent, 3-5 parts of a film-forming aid, 20-30 parts of styrene-acrylic emulsion, 0.1-0.5 part of a thickener; wherein, the SiO 2 aerogel slurry is prepared by uniformly dispersing a silane coupling agent and SiO 2 aerogel in an aqueous solution of polyvinyl alcohol. The coating has good adhesion and corrosion resistance, and has excellent heat-insulating and heat-preserving performance and anti-cracking performance.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and particularly relates to a SiO 2 aerogel water-based heat insulation and thermal insulation coating and a preparation method thereof. Background Art

[0002] How to make storage tanks safer, more economical and reasonable when storing oil products is a hot topic studied by scholars at home and abroad today. Under the background of a resource-saving society, preventing heat loss during transmission and improving energy utilization efficiency are great social needs. Therefore, heat insulation and thermal insulation coatings have emerged as the times require.

[0003] Due to characteristics such as light weight, good waterproof performance, and good toughness, heat insulation and thermal insulation coatings can integrate functions such as waterproofing, heat preservation, and external protection, and can simplify the construction process. With the rapid development of the oil production and petrochemical industries, they can save a large amount of energy and have good development prospects.

[0004] SiO 2 The interior of aerogel is composed of a large number of nano-scale (20 - 50μm) microporous structures, with a porosity of over 90%, making it the solid structure with the lowest density in the world. Due to its advantages such as high porosity, low density, and large specific surface area, SiO 2 aerogel exhibits excellent performance in heat insulation and is currently the solid material with the lowest thermal conductivity. Therefore, if it is effectively dispersed and added to coatings as a raw material, it can help improve the heat insulation and thermal insulation effect of coatings, and has good application prospects in heat insulation and thermal insulation coatings.

[0005] However, aerogel has defects in coatings such as poor dispersibility, easy agglomeration, and easy destruction of microporous structures (these defects will lead to unsatisfactory heat insulation effects of coatings), and these defects are also the bottlenecks restricting the development of aerogel coatings.

[0006] Therefore, how to develop a coating using SiO 2 aerogel as a raw material, which can overcome defects such as poor dispersibility and easy agglomeration of aerogel in coatings to achieve good heat insulation and thermal insulation effects of coatings, is exactly the difficulty that those skilled in the art are committed to solving. Summary of the Invention

[0007] To solve the deficiencies of the prior art mentioned in the above background art, the present application provides a SiO 2 aerogel water-based heat insulation and thermal insulation coating, and its technical solution is as follows:

[0008] By weight, the components of the SiO 2 aerogel water-based heat insulation and thermal insulation coating include:

[0009] 7 - 15 parts of water, 10 - 15 parts of hollow glass microspheres, SiO2 40 - 50 parts of aerogel slurry, 0.1 - 0.3 parts of the first neutralizing agent, 3 - 5 parts of film - forming auxiliary, 20 - 30 parts of styrene - acrylic emulsion, 0.1 - 0.5 parts of thickener; wherein, the SiO 2 The aerogel slurry is prepared by uniformly dispersing aerogel in an aqueous solution of polyvinyl alcohol. 2 The aerogel slurry is made by uniformly dispersing aerogel in an aqueous solution of polyvinyl alcohol.

[0010] In one embodiment, the preparation process of the styrene - acrylic emulsion is as follows:

[0011] Add surfactants, buffers, isooctyl acrylate, n - butyl acrylate, styrene, ethylene glycol dimethacrylate, and monomer acrylic acid into the first part of water, and disperse evenly to obtain a pre - emulsion;

[0012] Add the initiator into the second part of water to prepare an initiator solution;

[0013] Under stirring, heat the first part of the pre - emulsion to 65 - 80 °C, and add the first part of the initiator solution, and keep warm for 1 - 1.5 h; then add the second part of the pre - emulsion and the second part of the initiator solution, control the dropping time to be 3 - 4 h, after adding, heat up to 80 - 85 °C, and keep warm for 0.75 - 1 h; cool the system to 60 - 65 °C, and add the third part of the initiator solution, continue to keep warm for 0.5 - 1 h and then cool down, and adjust the pH of the system to 7 - 8 with the second neutralizing agent to obtain the styrene - acrylic emulsion;

[0014] Among them, by weight, the raw materials of the styrene - acrylic emulsion include: 15 - 20 parts of isooctyl acrylate, 10 - 14 parts of n - butyl acrylate, 30 - 40 parts of styrene, 0.5 - 2 parts of ethylene glycol dimethacrylate, 1 - 2 parts of monomer acrylic acid, and 30 - 50 parts of water;

[0015] The sum of the amounts of the first part of water and the second part of water is the total amount of raw material water; the sum of the amounts of the first part of the pre - emulsion and the second part of the pre - emulsion is the total amount of the pre - emulsion; the sum of the amounts of the first part of the initiator solution, the second part of the initiator solution, and the third part of the initiator solution is the total amount of the initiator solution.

[0016] In one embodiment, dissolve surfactants and buffers in the first part of water, and then add isooctyl acrylate, n - butyl acrylate, styrene, ethylene glycol dimethacrylate, and monomer acrylic acid, and disperse evenly at high speed to obtain a pre - emulsion.

[0017] In one embodiment, by weight, the raw materials of the styrene-acrylic emulsion include: 15-20 parts of isooctyl acrylate, 10-14 parts of n-butyl acrylate, 30-40 parts of styrene, 0.5-2 parts of ethylene glycol dimethacrylate, 1-2 parts of monomer acrylic acid, 0.3-0.5 parts of initiator, 0.4-0.7 parts of surfactant, 0.05-0.1 parts of buffer, and 30-50 parts of water;

[0018] Among them, the weight ratio of the first part of water to the second part of water is (10-15):(10-15); the weight ratio of the first part of the prefabricated emulsion to the second part of the prefabricated emulsion is (5-10):(45-70); the weight ratio of the first part of the initiator solution, the second part of the initiator solution, and the third part of the initiator solution is (3-5):(6-10):(3-5).

[0019] In one embodiment, by weight, the surfactant includes 0.3-0.5 parts of nonylphenol polyoxyethylene ether and 0.1-0.2 parts of sodium dodecyl sulfate; the buffer is sodium bicarbonate; the second neutralizer is AMP-30; the initiator is ammonium persulfate.

[0020] In one embodiment, the SiO 2 The preparation process of the aerogel slurry is as follows: Mix water and the aqueous polyvinyl alcohol solution evenly; then, under stirring, add the silane coupling agent and disperse it evenly; then, under stirring, add SiO 2 Aerogel and disperse it evenly to obtain a slurry; finally, grind the slurry to obtain SiO 2 Aerogel slurry.

[0021] In one embodiment, by weight, the raw materials of the SiO 2 Aerogel slurry include: 70-80 parts of water, 10-15 parts of aqueous polyvinyl alcohol solution, 5-8 parts of silane coupling agent, and 15-20 parts of SiO 2 Aerogel.

[0022] In one embodiment, the mass fraction of the aqueous polyvinyl alcohol solution is 20%-25%; the silane coupling agent is silane coupling agent KH560.

[0023] In one embodiment, the first neutralizer is one or a combination of more than one of DMAE, AMP-95, and ammonia water; the film-forming aid is one or a combination of more than one of propylene glycol methyl ether, propylene glycol butyl ether, propylene glycol phenyl ether, and dipropylene glycol methyl ether; the thickener is one or a combination of two of PU1191 and 299.

[0024] The present invention also provides a method for preparing the SiO 2 Aerogel water-based heat-insulating and heat-preserving coating as described above, which includes the following steps:

[0025] Add styrene-acrylic emulsion, water, the first neutralizing agent, film-forming aid, and thickener into a dispersion kettle, disperse evenly to obtain mixture M;

[0026] Under stirring, slowly add the SiO 2 aerogel slurry into mixture M, stir evenly; then, under stirring, slowly add hollow glass microspheres and stir evenly; detect and sieve to obtain the heat-insulating and heat-preserving coating.

[0027] Based on the above, compared with the prior art, the present invention has the following beneficial effects:

[0028] The SiO 2 aerogel water-based heat-insulating and heat-preserving coating provided by the present invention has good dispersion and high absorption capacity of SiO 2 aerogel in its components. There is good compatibility and bonding force between the styrene-acrylic emulsion and SiO 2 aerogel and hollow glass microspheres, making the coating have good adhesion and corrosion resistance, and excellent heat-insulating and heat-preserving performance and anti-cracking performance.

[0029] Other features and beneficial effects of the present invention will be described in the subsequent specification, and part of them will be obvious from the specification or understood by implementing the present invention. The objectives and other beneficial effects of the present invention can be achieved and obtained through the structures and / or components pointed out in the specification and claims. Specific Embodiments

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them; the technical features designed in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that all terms used in the present invention (including technical terms and scientific terms) have the same meanings as those generally understood by those of ordinary skill in the art to which the present invention belongs, and should not be construed as a limitation of the present invention; it should be further understood that the terms used in the present invention should be understood as having meanings consistent with their meanings in the context of this specification and the relevant art, and should not be understood in an idealized or overly formal sense, unless clearly defined as such in the present invention.

[0032] The present invention provides a kind of SiO 2Preferred practical example of the preparation method of aerogel water-based heat-insulating and heat-preserving coating, which includes the following steps:

[0033] Add styrene-acrylic emulsion, water, first neutralizing agent, film-forming aid, and thickener into the dispersion kettle, disperse evenly at low speed to obtain mixture M;

[0034] Under stirring, slowly add SiO 2 aerogel slurry into mixture M and stir evenly;

[0035] Then, under stirring, slowly add hollow glass microspheres and stir evenly;

[0036] After passing all inspection items, filter through a 60-mesh vibrating screen and fill into barrels to obtain a SiO 2 aerogel water-based heat-insulating and heat-preserving coating for storage tanks.

[0037] 1. The specific formula of the coating is:

[0038] By weight, its components include 7-15 parts of water, 10-15 parts of hollow glass microspheres, 40-50 parts of SiO 2 aerogel slurry, 0.1-0.3 parts of the first neutralizing agent, 3-5 parts of film-forming aid, 20-30 parts of styrene-acrylic emulsion, and 0.1-0.5 parts of thickener;

[0039] 2. The SiO 2 aerogel slurry is prepared by uniformly dispersing silane coupling agent and SiO 2 aerogel in an aqueous solution of polyvinyl alcohol. The operation example of its preparation method is:

[0040] Mix water and aqueous solution of polyvinyl alcohol evenly; then, under stirring, add silane coupling agent and disperse evenly; then, under stirring, add SiO 2 aerogel and disperse evenly to obtain a slurry; finally, grind the slurry to obtain SiO 2 aerogel slurry.

[0041] Among them, by weight, the raw materials of the SiO 2 aerogel slurry include: 70-80 parts of water, 10-15 parts of aqueous solution of polyvinyl alcohol, 5-8 parts of silane coupling agent, and 15-20 parts of SiO 2 aerogel. Among them, the mass fraction of the selected aqueous solution of polyvinyl alcohol can be 20%-25%; the silane coupling agent can be silane coupling agent KH560.

[0042] 3. The styrene-acrylic emulsion is a self-made emulsion, and the operation example of its preparation method is:

[0043] (1)Weigh the emulsion raw materials: By weight, the raw materials of the styrene-acrylic emulsion include 15-20 parts of isooctyl acrylate, 10-14 parts of n-butyl acrylate, 30-40 parts of styrene, 0.5-2 parts of ethylene glycol dimethacrylate, 1-2 parts of monomer acrylic acid, 0.3-0.5 parts of initiator, 0.4-0.7 parts of surfactant, 0.05-0.1 parts of buffer, and 30-50 parts of water;

[0044] (2)Dissolve the surfactant and buffer in the first part of water, and then add isooctyl acrylate, n-butyl acrylate, styrene, ethylene glycol dimethacrylate, and monomer acrylic acid, and disperse them evenly at high speed to obtain a prefabricated emulsion.

[0045] (3)Add the initiator to the second part of water to prepare an initiator solution;

[0046] (4)Under stirring, heat the first part of the prefabricated emulsion to 65-80 °C, and add the first part of the initiator solution, and keep it warm for 1-1.5 h; then add the second part of the prefabricated emulsion and the second part of the initiator solution, control the dropping time to be 3-4 h, after adding, heat it up to 80-85 °C, and keep it warm for 0.75-1 h; cool the system to 60-65 °C, and add the third part of the initiator solution, continue to keep it warm for 0.5-1 h and then cool it, and adjust the pH of the system to 7-8 with the second neutralizer to obtain the styrene-acrylic emulsion;

[0047] Among them, the sum of the amounts of the first part of water and the second part of water is the total amount of raw material water; the sum of the amounts of the first part of the prefabricated emulsion and the second part of the prefabricated emulsion is the total amount of the prefabricated emulsion; the sum of the amounts of the first part of the initiator solution, the second part of the initiator solution, and the third part of the initiator solution is the total amount of the initiator solution.

[0048] Among them, the weight ratio of the first part of water to the second part of water is (10-15):(10-15); the weight ratio of the first part of the prefabricated emulsion to the second part of the prefabricated emulsion is (5-10):(45-70); the weight ratio of the first part of the initiator solution, the second part of the initiator solution, and the third part of the initiator solution is (3-5):(6-10):(3-5).

[0049] For the selection of raw materials, the surfactant can be selected from 0.3-0.5 parts of nonylphenol polyoxyethylene ether and 0.1-0.2 parts of sodium dodecyl sulfate; the buffer can be selected from sodium bicarbonate; the second neutralizer can be selected from AMP-30; the initiator can be selected from ammonium persulfate.

[0050] The present invention also provides the following examples and comparative examples, and their formulations (unit: weight parts) are shown in Table 1 below:

[0051] Table 1

[0052]

[0053] Specifically, the specific implementation processes in the examples and comparative examples are as follows:

[0054] Example 1

[0055] A method for preparing a SiO 2 aqueous heat-insulating and heat-preserving coating of aerogel, comprising the following steps:

[0056] Step 1: Preparation of styrene-acrylic emulsion

[0057] Weigh the following component raw materials by weight: 15 parts by weight of isooctyl acrylate, 12 parts by weight of n-butyl acrylate, 32 parts by weight of styrene, 0.6 parts by weight of ethylene glycol dimethacrylate, 1.1 parts by weight of monomer acrylic acid, 0.3 parts by weight of initiator ammonium persulfate, 0.3 parts by weight of surfactant nonylphenol polyoxyethylene ether and 0.1 parts by weight of sodium dodecyl sulfate, 0.05 parts by weight of sodium bicarbonate, 35 parts by weight of deionized water.

[0058] Mix the surfactant nonylphenol polyoxyethylene ether, sodium dodecyl sulfate, sodium bicarbonate with 1 / 2 of the deionized water, stir and dissolve, then slowly add isooctyl acrylate, n-butyl acrylate, styrene, ethylene glycol dimethacrylate, monomer acrylic acid and disperse at high speed for 1 h to obtain a prefabricated emulsion for standby.

[0059] Mix 1 / 2 of the deionized water by mass fraction and ammonium persulfate as the initiator to obtain an initiator solution for standby. Add 1 / 10 of the prefabricated emulsion by mass fraction to the reactor, heat up to 70 °C under stirring, and then add 1 / 4 of the initiator solution (1 / 2 of the deionized water and the initiator mixed solution), and keep warm for 1 h.

[0060] Slowly drop 9 / 10 of the prefabricated emulsion by mass fraction and 2 / 4 of the initiator solution, and control the dropping time to be completed within 3 h, heat up to 80 °C, and keep warm for 1 h;

[0061] Cool down to 60 °C and drop 1 / 4 of the initiator solution, continue to keep warm for 30 min and then cool down, and adjust the pH to 8 with the neutralizer AMP-30 to obtain the styrene-acrylic emulsion.

[0062] Step 2: Preparation of SiO 2 aerogel slurry:

[0063] Add 70 parts of deionized water and 10 parts of 20% polyvinyl alcohol aqueous solution to the reactor and disperse evenly, disperse 5 parts of silane coupling agent KH560 at high speed for 5 minutes under stirring, and add 15 parts of SiO 2The aerogel is highly dispersed for 30 minutes. After the dispersion is completed, it is ground with zirconium beads for 1 hour to obtain SiO 2 aerogel slurry;

[0064] Step 3. Preparation of SiO 2 aqueous heat-insulating and heat-preserving coating for storage tanks:

[0065] 7 parts by weight of deionized water, 10 parts by weight of hollow glass microspheres, 48 parts by weight of SiO 2 aerogel slurry, 0.1 part by weight of the first neutralizing agent, 3 parts by weight of film-forming aid, 23 parts by weight of styrene-acrylic emulsion, 0.1 part by weight of thickener. After all inspection items are qualified, it is filtered through a 60-mesh vibrating screen and filled into barrels to obtain a kind of SiO 2 aqueous heat-insulating and heat-preserving coating for storage tanks.

[0066] In this example, the first neutralizing agent is DMAE; the film-forming aid is a mixture of propylene glycol methyl ether and propylene glycol butyl ether in a mass ratio of 1:1; the thickener is PU1191.

[0067] Example 2

[0068] Step 1. Preparation of styrene-acrylic emulsion:

[0069] Weigh the following component raw materials by weight: 17 parts by weight of isooctyl acrylate, 10 parts by weight of n-butyl acrylate, 36 parts by weight of styrene, 1.4 parts by weight of ethylene glycol dimethacrylate, 1.6 parts by weight of monomer acrylic acid, 0.4 parts by weight of initiator ammonium persulfate, 0.4 parts by weight of surfactant nonylphenol polyoxyethylene ether and 0.1 parts by weight of sodium dodecyl sulfate, 0.08 parts by weight of sodium bicarbonate, 42 parts by weight of deionized water.

[0070] Mix the surfactant nonylphenol polyoxyethylene ether, sodium dodecyl sulfate, sodium bicarbonate with 1 / 2 of the deionized water, stir and dissolve, then slowly add isooctyl acrylate, n-butyl acrylate, styrene, ethylene glycol dimethacrylate, monomer acrylic acid and disperse them at high speed for 1 h to obtain a prefabricated emulsion for standby.

[0071] Mix 1 / 2 of the deionized water and the initiator ammonium persulfate to obtain an initiator solution for standby. Add 1 / 10 of the prefabricated emulsion to the reactor, heat it up to 70 °C under stirring, and then add 1 / 4 of the initiator solution (a mixed solution of 1 / 2 of the deionized water and the initiator), and keep it warm for 1 h.

[0072] Slowly drop 9 / 10 of the prefabricated emulsion and 2 / 4 of the initiator solution, and control the dropping time to be completed in 3 h, then heat it up to 80 °C and keep it warm for 1 h;

[0073] Cool down to 60°C, add the initiator solution with a mass fraction of 1 / 4 dropwise, continue to keep warm for 30 min, then cool down, and adjust the pH to 8 with the neutralizing agent AMP-30 to obtain the styrene-acrylic emulsion.

[0074] Step 2. Preparation of SiO 2 aerogel slurry:

[0075] Add 70 parts of deionized water and 10 parts of 20% polyvinyl alcohol aqueous solution to the reactor and disperse evenly. Under stirring, disperse 5 parts of silane coupling agent KH560 at high speed for 5 min. Under stirring, add 15 parts of SiO 2 aerogel and disperse at high speed for 30 min. After dispersion, grind with zirconium beads for 1 h to obtain SiO 2 aerogel slurry;

[0076] Step 3. Preparation of SiO 2 aqueous heat-insulating and heat-preserving coating for storage tanks:

[0077] 12 parts by weight of deionized water, 13 parts by weight of hollow glass microspheres, 43 parts by weight of SiO 2 aerogel slurry, 0.2 part by weight of the first neutralizing agent, 4 parts by weight of film-forming aid, 26 parts by weight of styrene-acrylic emulsion, 0.3 part by weight of thickener. After passing all inspection items, filter with a 60-mesh vibrating screen and fill into barrels to obtain an SiO 2 aqueous heat-insulating and heat-preserving coating for storage tanks.

[0078] In this example, the first neutralizing agent is ammonia water; the film-forming aid is a mixture of propylene glycol methyl ether and diethylene glycol methyl ether with a mass ratio of 1:1; the thickener is 299.

[0079] Example 3

[0080] Step 1. Preparation of styrene-acrylic emulsion:

[0081] Weigh the following component raw materials by parts by weight: 20 parts by weight of isooctyl acrylate, 14 parts by weight of n-butyl acrylate, 40 parts by weight of styrene, 1.8 parts by weight of ethylene glycol dimethacrylate, 2 parts by weight of monomer acrylic acid, 0.5 part by weight of initiator ammonium persulfate, 0.5 part by weight of surfactant nonylphenol polyoxyethylene ether and 0.2 part by weight of sodium dodecyl sulfate, 0.1 part by weight of sodium bicarbonate, AMP-30, 49 parts by weight of deionized water.

[0082] Mix the surfactant nonylphenol polyoxyethylene ether, sodium dodecyl sulfate, and sodium bicarbonate with 1 / 2 mass fraction of deionized water, stir and dissolve, then slowly add isooctyl acrylate, n-butyl acrylate, styrene, ethylene glycol dimethacrylate, and monomer acrylic acid and disperse at high speed for 1 h to obtain a prefabricated emulsion for standby.

[0083] Mix deionized water with a mass fraction of 1 / 2 and ammonium persulfate as the initiator to obtain the initiator solution for standby. Add the prefabricated emulsion with a mass fraction of 1 / 10 to the reactor and heat it to 70 °C under stirring, then add the initiator solution (a mixed solution of deionized water with a mass fraction of 1 / 2 and the initiator) with a mass fraction of 1 / 4, and keep it warm for 1 h.

[0084] Slowly dropwise add the prefabricated emulsion with a mass fraction of 9 / 10 and the initiator solution with a mass fraction of 2 / 4. Control the dropping time to be completed within 3 h, then heat it up to 80 °C and keep it warm for 1 h;

[0085] Cool down to 60 °C and dropwise add the initiator solution with a mass fraction of 1 / 4. Continue to keep it warm for 30 min and then cool it down. Adjust the pH to 8 with the neutralizing agent AMP-30 to obtain the styrene-acrylic emulsion.

[0086] Step 2. Preparation of SiO 2 aerogel slurry:

[0087] Add 70 parts of deionized water and 10 parts of 20% polyvinyl alcohol aqueous solution to the reactor and disperse them evenly. Under stirring, disperse 5 parts of silane coupling agent KH560 at high speed for 5 minutes. Under stirring, add 15 parts of SiO 2 aerogel and disperse it at high speed for 30 minutes. After the dispersion is completed, grind it with zirconium beads for 1 hour to obtain SiO 2 aerogel slurry;

[0088] Step 3. Preparation of SiO 2 aqueous heat-insulating and heat-preserving coating for storage tanks:

[0089] 15 parts by weight of deionized water, 15 parts by weight of hollow glass microspheres, 50 parts by weight of SiO 2 aerogel slurry, 0.3 part by weight of the first neutralizing agent, 5 parts by weight of film-forming auxiliary agent, 30 parts by weight of styrene-acrylic emulsion, 0.5 part by weight of thickener. After passing all inspection items, filter it with a 60-mesh vibrating screen and fill it into barrels to obtain a kind of SiO 2 aqueous heat-insulating and heat-preserving coating for storage tanks.

[0090] Comparative Example 1

[0091] Adopt a commercially available heat-insulating and heat-preserving coating of the same type, specifically a hollow glass microsphere type heat-insulating and heat-preserving coating.

[0092] Comparative Example 2

[0093] Adopt a commercially available heat-insulating and heat-preserving coating of the same type, specifically SiO 2 aerogel heat-insulating and heat-preserving coating.

[0094] Comparative Example 3

[0095] The difference between this comparative example and Example 1 is only that: the styrene-acrylic emulsion added is not self-made, but the styrene-acrylic emulsion with the commercial brand of Badfu 998A is used, and the addition amounts of hollow glass microspheres and SiO 2 aerogel slurry (thermal insulation filler) are only 10 parts and 20 parts respectively, and other conditions are the same as those in Example 1.

[0096] Note: In this comparative example, when adding an equal amount of (thermal insulation filler, that is, hollow glass microspheres and SiO 2 aerogel slurry), the paint shows a large viscosity and non-flowing phenomenon, and there are defects such as great construction difficulty and cracking and non-film-forming. Therefore, the paint can only be prepared by reducing its addition amount.

[0097] Comparative Example 4

[0098] The difference between this comparative example and Example 1 is only that: the styrene-acrylic emulsion added is not self-made, but the styrene-acrylic emulsion with the commercial brand of BLJ-6619 is used, and the addition amounts of hollow glass microspheres and SiO 2 aerogel slurry (thermal insulation filler) are only 13 parts and 15 parts respectively, and other conditions are the same as those in Example 1.

[0099] Note: In this comparative example, when adding an equal amount of (thermal insulation filler, that is, hollow glass microspheres and SiO 2 aerogel slurry), the paint shows a large viscosity and non-flowing phenomenon, and there are defects such as great construction difficulty and cracking and non-film-forming. Therefore, the paint can only be prepared by reducing its addition amount.

[0100] Comparative Example 5

[0101] The difference between this comparative example and Example 1 is only that: the styrene-acrylic emulsion added is not self-made, but the styrene-acrylic emulsion with the commercial brand of SD-800 is used, and the addition amounts of hollow glass microspheres and SiO 2 aerogel slurry (thermal insulation filler) are only 15 parts and 10 parts respectively, and other conditions are the same as those in Example 1.

[0102] Note: In this comparative example, when adding an equal amount of (thermal insulation filler, that is, hollow glass microspheres and SiO 2 aerogel slurry), the paint shows a large viscosity and non-flowing phenomenon, and there are defects such as great construction difficulty and cracking and non-film-forming. Therefore, the paint can only be prepared by reducing its addition amount.

[0103] Comparative Example 6

[0104] The difference between this comparative example and Example 1 is only that: the silane coupling agent KH560 is not added during the preparation of the SiO 2 aerogel slurry, and other conditions are the same as those in Example 1.

[0105] Comparative Example 7

[0106] The difference between this comparative example and Example 1 is that the number of hollow glass microspheres added is 8, SiO 2 The number of parts of the aerogel slurry was 45, and other conditions were consistent with those in the embodiment.

[0107] Comparative Example 8

[0108] The difference between this comparative example and Example 1 is that the number of hollow glass microspheres added is 20, SiO 2 The number of parts of the aerogel slurry was 50, and other conditions were consistent with those in the embodiment.

[0109] The coatings prepared in the examples and comparative examples were subjected to performance tests, and the test results are shown in Table 2:

[0110] Table 2 Performance data of examples and comparative examples

[0111]

[0112] Analyzing the above test results, we can know that:

[0113] (1) Comparison results between Example 1 and Comparative Examples 1-2 show

[0114] The coating prepared by the present invention has good anti-corrosion performance, thermal insulation performance and excellent single-pass non-cracking film thickness, effectively avoiding the problems of poor aerogel dispersion, easy agglomeration, and easy structural damage during use, and various indicators are better than the comparative example (commercially available coatings of the same type). It can be seen that the present invention is a water-based thermal insulation coating with good performance, which can be applied to the thermal insulation of the outer walls of various storage tanks.

[0115] (2) Comparison of the examples and comparative examples 3-5 shows that the self-made emulsion of the present invention has stronger absorption capacity, mechanical properties, corrosion resistance and thick film anti-cracking performance for thermal insulation fillers than the commercially available emulsion. The self-made aerogel slurry effectively ensures the dispersion, storage stability and thermal insulation performance of the aerogel in the coating.

[0116] (3) The comparison results between the embodiment and comparative example 6 show that: compared with the embodiment, comparative example 6 does not use silane coupling agent to SiO 2 The mechanical properties, anti-corrosion properties, and thermal insulation properties of the obtained coating deteriorate after pretreatment of the aerogel slurry.

[0117] (4) The comparison results between the examples and comparative examples 7-8 show that compared with the examples, the hollow glass microspheres and SiO 2When the proportion of the aerogel slurry is not within the scope defined in this application, the heat insulation performance of the coating prepared in Comparative Example 7 deteriorates, and the mechanical properties, anti-corrosion properties, and heat insulation performance of the coating prepared in Comparative Example 8 deteriorate.

[0118] Summarize the SiO 2 performance results of the aerogel waterborne heat insulation and thermal insulation coating, which has the following technical innovation points and beneficial effects:

[0119] 1. The self-made styrene-acrylic emulsion in the present invention has good compatibility and bonding force with SiO 2 aerogel and hollow glass microspheres. Compared with commercially available emulsions, it can absorb more than 20% of heat insulation and thermal insulation materials; it can also provide beneficial adhesion (≥1.5 MPa), acid and alkali resistance (72 h), and salt spray resistance (240 h).

[0120] 2. The SiO 2 aerogel slurry used in the present invention modifies the surface structure and state of SiO 2 aerogel by using two parts of groups of silane coupling agents, improves the dispersibility of SiO 2 aerogel in the emulsion, and further improves the heat insulation and thermal insulation performance of the coating (thermal conductivity is 0.02 - 0.03 W / (m·K)); uses an aqueous solution of polyvinyl alcohol to improve the anti-cracking ability of the paint film, so that a single-layer paint film does not crack at 1 mm.

[0121] In summary, the SiO 2 aerogel waterborne heat insulation and thermal insulation coating and its preparation method provided by the present invention use a self-made styrene-acrylic emulsion and an aerogel slurry in combination with components such as hollow glass microspheres, which can better improve the dispersibility, storage stability, and heat insulation and thermal insulation effect of SiO 2 aerogel in the coating. The prepared coating has good adhesion and corrosion resistance, and excellent heat insulation and thermal insulation performance and anti-cracking performance.

[0122] It should be noted that:

[0123] In this article, "~" is used to define the protection scope, and its protection scheme includes the two endpoint values of this "~".

[0124] In addition to the actual selections reflected in the above specific embodiments, preferably, the first neutralizing agent can be selected from one or more combinations of DMAE, AMP-95, and ammonia water, including but not limited to the above embodiment schemes.

[0125] In addition to the actual selections reflected in the above specific embodiments, preferably, the film-forming aid can be selected from one or more combinations of propylene glycol methyl ether, propylene glycol butyl ether, propylene glycol phenyl ether, and dipropylene glycol methyl ether, including but not limited to the above embodiment schemes.

[0126] In addition to the actual selections reflected in the above specific embodiments, preferably, the thickener can be selected from one or a combination of two of PU1191 and 299, including but not limited to the solutions of the above embodiments.

[0127] The specific parameters or some common reagents in the above embodiments are specific embodiments or preferred embodiments under the concept of the present invention, rather than limitations thereto; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

[0128] In addition, unless otherwise specified, the raw materials used can also be conventional commercially available products in the art or prepared by conventional methods in the art.

[0129] In addition, those skilled in the art should understand that although there are many problems in the prior art, each embodiment or technical solution of the present invention can be improved in only one or several aspects, and it is not necessary to solve all the technical problems listed in the prior art or the background art at the same time. Those skilled in the art should understand that the content not mentioned in a claim should not be regarded as a limitation to that claim.

[0130] Although terms such as epoxy resin and amine curing agent are used more frequently in this article, the possibility of using other terms is not excluded. These terms are only used to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention; the terms "first", "second", etc. (if any) in the description and claims of the embodiments of the present invention are used to distinguish similar objects and do not have to be used to describe a specific order or sequence.

[0131] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A SiO 2 aerogel water-based heat insulation coating, It is characterized in that: By weight, its components include: 7 to 15 parts of water, 10 to 15 parts of hollow glass microspheres, SiO 2 40 to 50 parts of aerogel slurry, 0.1 to 0.3 parts of the first neutralizing agent, 3 to 5 parts of film-forming aids, 20 to 30 parts of styrene-acrylic emulsion, 0.1 to 0.5 parts of thickener; Among them, the SiO 2 aerogel slurry is prepared by uniformly dispersing an aerogel in an aqueous solution of polyvinyl alcohol, which is made from a silane coupling agent and SiO 2 The preparation process of the styrene-acrylic emulsion is as follows: Add surfactant, buffer, isooctyl acrylate, n-butyl acrylate, styrene, ethylene glycol dimethacrylate, and monomer acrylic acid into the first part of water, and disperse evenly to obtain a prefabricated emulsion; Add the initiator into the second part of water to prepare an initiator solution; Under stirring, heat the first part of the prefabricated emulsion to 65 - 80 °C, and add the first part of the initiator solution, and keep warm for 1 - 1.5 h; then add the second part of the prefabricated emulsion and the second part of the initiator solution, control the dropping time to be 3 - 4 h, after adding, heat up to 80 - 85 °C, and keep warm for 0.75 - 1 h; cool the system to 60 - 65 °C, and add the third part of the initiator solution, continue to keep warm for 0.5 - 1 h and then cool down, and adjust the pH of the system to 7 - 8 with the second neutralizing agent to obtain the styrene-acrylic emulsion; Among them, by weight, the raw materials of the styrene-acrylic emulsion include: 15 - 20 parts of isooctyl acrylate, 10 - 14 parts of n-butyl acrylate, 30 - 40 parts of styrene, 0.5 - 2 parts of ethylene glycol dimethacrylate, 1 - 2 parts of monomer acrylic acid, and 30 - 50 parts of water; The sum of the amounts of the first part of water and the second part of water is the total amount of raw material water; the sum of the amounts of the first part of the prefabricated emulsion and the second part of the prefabricated emulsion is the total amount of the prefabricated emulsion; the sum of the amounts of the first part of the initiator solution, the second part of the initiator solution, and the third part of the initiator solution is the total amount of the initiator solution.

2. The SiO 2 aerogel water-based heat-insulating and heat-preserving coating It is characterized in that: Dissolve the surfactant and buffer in the first part of water, and then add isooctyl acrylate, n-butyl acrylate, styrene, ethylene glycol dimethacrylate, and monomer acrylic acid, and disperse evenly at high speed to obtain a prefabricated emulsion.

3. The SiO 2 aerogel water-based heat insulation coating It is characterized in that: By weight, the raw materials of the styrene-acrylic emulsion include: 15 - 20 parts of isooctyl acrylate, 10 - 14 parts of n-butyl acrylate, 30 - 40 parts of styrene, 0.5 - 2 parts of ethylene glycol dimethacrylate, 1 - 2 parts of monomer acrylic acid, 0.3 - 0.5 parts of initiator, 0.4 - 0.7 parts of surfactant, 0.05 - 0.1 parts of buffer, and 30 - 50 parts of water; Among them, the weight ratio of the first part of water to the second part of water is (10 - 15):(10 - 15); The weight ratio of the first part of the prefabricated emulsion to the second part of the prefabricated emulsion is (5 - 10):(45 - 70); The weight ratio of the first part of the initiator solution, the second part of the initiator solution, and the third part of the initiator solution is (3 - 5):(6 - 10):(3 - 5).

4. The SiO according to claim 3 2 aerogel water-based heat-insulating and heat-preserving coating It is characterized in that: By weight, the surfactant includes 0.3 - 0.5 parts of nonylphenol polyoxyethylene ether and 0.1 - 0.2 parts of sodium dodecyl sulfate; The buffer is sodium bicarbonate; The initiator is ammonium persulfate.

5. The SiO 2 aerogel water-based heat-insulating and heat-preserving coating It is characterized in that: The SiO 2 The preparation process of the aerogel slurry is as follows: Mix water and an aqueous solution of polyvinyl alcohol evenly; then, under stirring, add a silane coupling agent and disperse it evenly; then, under stirring, add SiO 2 aerogel and disperse it evenly to obtain a slurry; finally, grind the slurry to obtain an SiO 2 aerogel slurry.

6. The SiO according to claim 5 2 aerogel water-based heat-insulating and heat-preserving coating It is characterized in that, By weight, the SiO 2 raw materials of the aerogel slurry include: 70-80 parts of water, 10-15 parts of polyvinyl alcohol aqueous solution, 5-8 parts of silane coupling agent, and SiO 2 aerogel 15-20 parts.

7. The SiO 2 aerogel water-based heat insulation coating according to claim 5 It is characterized in that: The mass fraction of the polyvinyl alcohol aqueous solution is 20% - 25%; The silane coupling agent is silane coupling agent KH560.

8. The SiO 2 aerogel water-based heat insulation coating according to any one of claims 1-7 It is characterized in that: The first neutralizing agent is one or a combination of DMAE, AMP-95, and ammonia water; The film-forming auxiliary is one or a combination of propylene glycol methyl ether, propylene glycol butyl ether, propylene glycol phenyl ether, and dipropylene glycol methyl ether; The thickener is one or a combination of PU1191 and 299.

9. A method for preparing an SiO 2 aerogel water-based heat-insulating and heat-preserving coating according to any one of claims 1-8, It is characterized in that it includes the following steps: Add styrene-acrylic emulsion, water, the first neutralizing agent, film-forming auxiliary, and thickener into a dispersion kettle, disperse evenly to obtain mixture M; Under stirring, slowly add the SiO 2 aerogel slurry into the mixture M, and stir evenly; then, under stirring, slowly add hollow glass microspheres and stir evenly; after passing the inspection, sieve to obtain the heat-insulating and heat-preserving coating.

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