Organic-inorganic composite emulsion, preparation method and application of organic-inorganic composite emulsion in multifunctional inorganic coating

Abstract

The invention relates to an organic-inorganic composite emulsion, a preparation method and an application of the organic-inorganic composite emulsion in a multifunctional inorganic coating, and belongs to the field of coatings, the organic-inorganic composite emulsion comprises an organic component and an inorganic component, through an organic-inorganic hybridization method, an organic emulsion is introduced into an inorganic phase, potassium silicate is chemically modified, the number of active functional groups (silanol groups) of the potassium silicate is reduced, and the organic-inorganic composite emulsion is prepared. The reaction activity of the system is reduced, and the stability of the system is improved; meanwhile, due to the alkali-rich microporous structure of the organic-inorganic composite emulsion, the system has an antiviral function. The multifunctional inorganic coating with antiviral, anti-formaldehyde, antibacterial, mildew-proof and A-grade flame-resistant properties is prepared, and the antibacterial and antiviral properties are efficient, lasting and stable due to the fact that the microcellular structure of the organic and inorganic composite emulsion is matched with the high alkalinity of a system; meanwhile, the number of active functional groups is reduced by an organic-inorganic hybridization method, and the selection of raw materials is wider.

Description

Technical Field

[0001] The invention belongs to the field of coatings, and in particular relates to an organic-inorganic composite emulsion, a preparation method and application thereof in multifunctional inorganic coatings. Background Art

[0002] With the development of cities, the gradual concentration of urban population, the high-rise residential buildings and the development of the catering industry, the possibility of fire is increasing. In order to maximize the protection of people’s lives and property, the state has introduced a series of relevant policies and management regulations. Among them, the fire protection code GB 50222 "Fire protection code for interior decoration design of buildings" revised in 2017 stipulates the building flame retardant standards that different buildings need to meet. This is also the main reason for the rise of inorganic coatings in China, because inorganic coatings are Class A non-combustible materials.

[0003] During the indoor decoration process, most decoration materials release formaldehyde, which causes the air quality to deteriorate and harms health. At the same time, antibacterial and antiviral functional coatings are increasingly attracting the attention of consumers. However, due to the presence of highly active alkali metal silicate substances in the system, existing inorganic coatings are selective for raw materials. When mixed with raw materials, they are prone to post-thickening and degradation of physical and chemical properties, making it difficult to prepare multifunctional inorganic coatings. For example, CN113337219A discloses an antibacterial and antiviral formaldehyde-removing coating and its preparation method. The antibacterial and antiviral properties obtained by the strong redox action of negative oxygen ion powder are not durable, and the preparation process of nano inorganic resin is relatively complicated, causing great pollution to the environment during the preparation process, and the cost is also high. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an organic-inorganic composite emulsion, a preparation method and its application in a multifunctional inorganic coating. On the basis of traditional inorganic coatings, in order to improve the stability of the system, an organic emulsion is introduced into the inorganic phase by an organic-inorganic hybridization method, potassium silicate is chemically modified, and the number of active functional groups (silanol groups) of potassium silicate is reduced to reduce the reactivity of the system and improve the stability of the system; at the same time, the alkali-rich microporous structure of the organic-inorganic composite emulsion enables the system to have an antiviral function. In addition, due to the reduction in the number of active functional groups in the system, the system has a wider selection of raw materials and is easier to prepare multifunctional inorganic coatings.

[0005] The present invention prepares a multifunctional inorganic coating which is antiviral, anti-formaldehyde, antibacterial and mildew-proof, and Class A flame retardant. Since the antibacterial and antiviral properties are achieved through the microporous structure of the organic-inorganic composite emulsion and the high alkalinity of the system, the antibacterial and antiviral properties are efficient, durable, and stable. At the same time, the organic-inorganic hybridization method reduces the number of active functional groups, and the choice of raw materials is more extensive.

[0006] To solve the above problems, the present invention is implemented through the following technical solutions:

[0007] The first object of the present invention is:

[0008] Provided is a method for preparing an organic-inorganic composite emulsion, which comprises the following components in parts by weight:

[0009] 1-20 parts of styrene monomer, 1-12 parts of butyl acrylate monomer, 1-8 parts of butyl methacrylate monomer, 1-8 parts of acrylic acid monomer, 1-2 parts of ammonium persulfate, 1-2 parts of sodium dodecyl sulfate, 1-4 parts of sodium lignin sulfonate, 10-40 parts of potassium silicate, 1-20 parts of sodium silicate, and 30-60 parts of deionized water;

[0010] The inorganic component and the organic component are polymerized by an in-situ polymerization method at a mass ratio of 1.7 to 2:1 at 75 to 85°C;

[0011] It states:

[0012] The organic components include: styrene monomer, butyl acrylate monomer, butyl methacrylate monomer, acrylic acid monomer;

[0013] Inorganic components include potassium silicate and sodium silicate;

[0014] It comprises the following preparation steps:

[0015] S1. Synthesis of core material:

[0016] Weigh a certain amount of sodium lignin sulfonate and add it to an appropriate amount of deionized water, stir it with a magnetic force for 30 minutes to make it evenly mixed, add potassium silicate and sodium silicate dissolved in an appropriate amount of deionized water, stir it at 8000 rpm / min for 5 minutes to make it evenly mixed, and obtain the core material;

[0017] The sodium lignin sulfonate is a renewable natural polymer with a long hydrophobic skeleton and abundant hydrophilic side chains. It is amphiphilic and is used to stabilize potassium silicate and sodium silicate, improve stability, and is natural and environmentally friendly. Sodium lignin sulfonate not only helps to improve the stability of the emulsion, but also plays an important role in the morphology and particle size distribution of the microcapsules.

[0018] S2. Synthesis of wall materials and microencapsulation process:

[0019] Add styrene monomer, butyl acrylate monomer, butyl methacrylate monomer, acrylic acid monomer and the core material prepared in step S1 to an appropriate amount of deionized water, stir magnetically for 30 minutes to mix them evenly, heat the water bath to 75-80° C., inject ammonium persulfate dissolved in 10 ml of deionized water with a syringe within 0.5 h, and after the injection of ammonium persulfate, inject sodium dodecyl sulfate in the same manner, and finally react in a constant temperature water bath at 80-85° C. for 3-4 hours to obtain an organic-inorganic composite emulsion in the form of microcapsules;

[0020] The monomer undergoes polymerization reaction on the outer surface of the core material under the action of ammonium persulfate and sodium dodecyl sulfate, and is deposited on the surface of the core material to form microcapsules.

[0021] When the core-to-wall ratio (mass ratio of inorganic components to organic components) is 1.7 to 2:1, the organic-inorganic composite emulsion has better thermal stability while balancing various properties such as flexibility, crack resistance, hardness, and flame retardancy.

[0022] A preferred example of the preparation method of the organic-inorganic composite emulsion of the present invention is:

[0023] The modulus of the potassium silicate is 3.9±0.2;

[0024] The modulus of sodium silicate is 3.2±0.2.

[0025] A preferred example of the preparation method of the organic-inorganic composite emulsion of the present invention is:

[0026] The organic-inorganic composite emulsion has the following performance parameters:

[0027] Solid content: 25-60%;

[0028] pH: 10.5~11.5;

[0029] Tg: 5~25℃.

[0030] The organic-inorganic composite emulsion of the present invention wraps the organic phase on the surface of the inorganic phase through a hybridization method (passivating the surface activity of the inorganic phase and improving the stability of the system). First, the inorganic phase in the organic-inorganic composite emulsion reacts to form a cross-linked and entangled three-dimensional network structure, and the surface silicate groups undergo substitution reactions with the groups on the long chains of the organic phase, so that the long chains of the organic phase undergo grafting and interlacing reactions to form a network structure, which orderly wraps the surface of the inorganic phase to form a core-shell coated microcapsule structure.

[0031] The second object of the present invention is:

[0032] Provided is an organic-inorganic composite emulsion, which is prepared according to the above-mentioned preparation method.

[0033] The third invention object of the present invention is:

[0034] Provided is a multifunctional inorganic coating comprising the following components in parts by weight:

[0035] 10-50 parts of water, 0.4-0.8 parts of thickener, 0.1-0.5 parts of pH regulator, 0.5-1 parts of defoamer, 0.2-1 parts of dispersant, 0.2-1 parts of wetting agent, 5-15 parts of calcined kaolin, 3-8 parts of diatomaceous earth, 10-18 parts of titanium dioxide, 10-20 parts of silicon micropowder, 13-30 parts of the organic-inorganic composite emulsion prepared above, 1-10 parts of anti-formaldehyde emulsion, 0.1-1 parts of anti-formaldehyde auxiliary agent, and 0.1-2 parts of film-forming auxiliary agent.

[0036] A preferred example of the multifunctional inorganic coating of the present invention is:

[0037] It includes one or more of the following characteristics:

[0038] The thickener is one or a combination of hydroxyethyl cellulose, bio-gum, and modified bentonite;

[0039] The pH regulator is one or a combination of sodium hydroxide, organic alcohol ammonia, and organic amine pH regulators;

[0040] The defoaming agent is one or a combination of mineral oil defoaming agent and silicone defoaming agent;

[0041] The dispersant is one or a combination of polycarboxylic acid anion type and polyoxyethylene alkyl ether type;

[0042] The wetting agent is one or a combination of isotridecyl polyethylene glycol ethers, fatty alcohols, and nonionic surfactants;

[0043] The calcined kaolin has a particle size distribution shape of a book page structure, a hardness of 5 to 7, and an oil absorption of 60 to 80 g / 100 g;

[0044] The diatomite has a particle size distribution shape of a round sieve hollow column porous structure, a hardness of 5 to 7, an oil absorption of 100 to 130 g / 100 g, and SiO 2 Content 60~90%; SiO in diatomite 2 It is an amorphous non-crystalline structure, which makes the microporous structure orderly arranged. Due to its large lattice porosity, it effectively reduces the internal stress generated when the organic-inorganic composite emulsion and the substrate surface are cured through the silicification reaction, greatly reducing the risk of cracking of the paint film applied on the substrate;

[0045] At the same time, the amorphous structure of diatomaceous earth has no clear structural order between the atoms, has a clustered arrangement, high strength, and no lattice structure inside, which makes it have excellent thermal stability. After being wrapped by the organic-inorganic composite emulsion during the coating production process, the thermal stability of the coating is greatly improved.

[0046] The titanium dioxide has a spherical particle size distribution, a hardness of 5 to 7, and an oil absorption of 18 to 25 g / 100 g.

[0047] The particle size distribution of the silicon micropowder is a needle-like structure, the particle size is 2.5 to 45 μm, the hardness is 6 to 8, the oil absorption is 20 to 26 g / 100 g, and the SiO 2 The content is more than 99%. The particle size distribution of silicon micropowder is a needle-like structure, which effectively penetrates into the gaps of the microporous structure of diatomite and organic-inorganic composite emulsion, so that the pigment filler and the organic-inorganic composite emulsion are fully combined, wrapped, connected and reacted, effectively improving the density of the coating; at the same time, SiO 2 The content is over 99%, which improves the hardness, scrub resistance, wet rubbing resistance and other properties of the coating.

[0048] A preferred example of the multifunctional inorganic coating of the present invention is:

[0049] The anti-formaldehyde emulsion is an anionic odorless styrene-acrylic emulsion; the anti-formaldehyde auxiliary is trishydroxymethylaminomethane; the anti-formaldehyde auxiliary reacts with formaldehyde in a molar ratio of 1:2, and the anti-formaldehyde auxiliary is matched with the anti-formaldehyde emulsion to obtain efficient, lasting and stable anti-formaldehyde performance. The anti-formaldehyde emulsion can connect the powder material to make its continuous phase evenly distributed; the anti-formaldehyde auxiliary can migrate to the surface of the coating film and fully contact the formaldehyde in the air; the uniform dispersion of the emulsion and the auxiliary trihydroxy structure quickly capture formaldehyde, achieving the goal of removing free formaldehyde pollutants in the environment with target anchoring; the perfect match of the emulsion and the auxiliary, using their respective advantages to work together, achieve functional superposition and complementary performance, and ensure the stability of the anti-formaldehyde effect between batches; while effectively reducing costs (maintaining the best cost performance), it can also ensure efficient, lasting and stable anti-formaldehyde performance, and the addition of the anti-formaldehyde emulsion also effectively improves the scrub resistance of the coating.

[0050] A preferred example of the multifunctional inorganic coating of the present invention is:

[0051] The film-forming aid is 2,4,4-trimethylpentane-1,3-diylbis(2-methylpropionate), which is the isomer of hexadecyl alcohol ester. While the film-forming aid helps the anti-formaldehyde emulsion to form a film, it is interspersed in the silicon-oxygen bond space network structure of the organic-inorganic composite emulsion through a multi-branched chain structure. The ester group and chain structure of the film-forming aid increase the spatial steric hindrance, making it difficult for the silanol group to undergo a condensation reaction, reducing the number of active functional groups and improving the stability of the system.

[0052] The fourth invention objective of the present invention is:

[0053] A method for preparing the multifunctional inorganic coating described above is provided, which comprises the following preparation steps:

[0054] s1. Add water to the container and stir at a stirring speed of 300 to 500 rpm; add thickener, pH adjuster, dispersant, wetting agent, one-third amount of defoamer, anti-formaldehyde additive to the water in sequence and stir at a stirring speed of 700 to 900 rpm for 3 ± 1 minutes;

[0055] s2. Add the pigment filler to the mixture of step s1 and stir at a stirring speed of 1200 to 1800 rpm for 20 ± 5 minutes;

[0056] s3. After the stirring in step s2 is completed, the stirring speed is modulated to 700 to 900 rpm, and the organic-inorganic composite emulsion, the anti-formaldehyde emulsion, and the film-forming aid prepared according to claim 1 are sequentially added and stirred for 5 ± 2 minutes; the remaining portion of the defoamer is added and stirred for 20 ± 5 minutes, and stirring is continued to obtain the multifunctional inorganic coating;

[0057] The pigments and fillers are calcined kaolin, diatomaceous earth, titanium dioxide and silicon powder.

[0058] The present invention solves the problem of short-lasting antibacterial and antiviral performance, and is efficient, healthy and environmentally friendly; at the same time, the method for obtaining the anti-formaldehyde performance is simple and easy to produce, and the cost is effectively reduced, the performance is more efficient, durable and stable, and the defects of the prior art are overcome.

[0059] (1) There are also antiviral coatings on the market, but most of them are made by adding Ag + , Cu 2+ , quaternary ammonium salt additives to obtain antiviral function, and the antiviral function of the present invention is imparted by the emulsion, and there is no need to add additional antiviral functional additives, which reduces the biocidal hazards caused by antiviral additives and is healthier and more environmentally friendly.

[0060] (ii) The emulsion used in the present invention is an organic-inorganic composite emulsion obtained by an organic-inorganic hybridization method:

[0061] a. First, the molecular chain structure in the organic emulsion is designed through active controllable technology, so that the alkali metal silicate and the emulsion molecular chain are combined through chemical bonds to achieve a higher anchoring effect, and the organic and inorganic components interact with each other to achieve better stability, thereby improving the poor stability of the existing inorganic coating system;

[0062] b. Secondly, organic-inorganic hybridization increases the microporous strength in the paint film by two times, forming more microporous structures:

[0063] More microporous structures can improve dry hiding by changing the light reflection index, reduce the amount of titanium dioxide used, save costs, and reduce energy consumption; more microporous structures are easier to capture viruses, and combined with the high alkalinity of the inorganic coating system, they can kill harmful viruses and bacteria and obtain antiviral properties.

[0064] The mechanism of the virus inactivation process of this technical solution is:

[0065] The organic-inorganic hybrid method prepares more microporous structures, which are easier to capture viruses; the inorganic coating has a high pH, ​​strong alkalinity, and a large electrolyte concentration. When it encounters water vapor in the atmosphere, it can release electrolytes. The electrolytes and the charged groups on the cell membrane surface interact electrostatically to cause membrane damage. At the same time, under high alkaline conditions, the phosphate groups in the RNA segments can be destroyed, resulting in the breakage of the RNA segments, so that the hydrogen bonds of the genetic material are destroyed and the structure is changed, thereby inactivating viruses and bacteria. The multifunctional inorganic coating with inactivation of viruses of the present invention can help prevent the spread of viruses attached to the wall.

[0066] (III) Anti-formaldehyde additives are combined with anti-formaldehyde emulsion to obtain efficient, long-lasting and stable anti-formaldehyde performance:

[0067] a. Anti-formaldehyde emulsion can connect powders to make their continuous phase evenly distributed; anti-formaldehyde additives can migrate to the surface of the coating film and fully contact with formaldehyde in the air to improve the efficiency of formaldehyde removal; the perfect combination of anti-formaldehyde emulsion and anti-formaldehyde additives successfully achieves the goal of removing free formaldehyde pollutants in the environment by target anchoring.

[0068] b. Utilize their respective advantages, synergistic effects, and functional superposition; complement the performance to ensure the stability of the anti-formaldehyde effect between batches; the complete combination of anti-formaldehyde emulsion and anti-formaldehyde additive can effectively reduce costs while ensuring efficient, long-lasting, and stable anti-formaldehyde performance and improving scrub resistance.

[0069] c. The use of film-forming aids not only helps the anti-formaldehyde emulsion to form a film, but also greatly improves the stability of the system through the steric hindrance effect.

[0070] d. Compounding of organic-inorganic composite emulsion and anti-formaldehyde functional emulsion; on the basis of traditional inorganic coatings, it solves the problem of system instability and subsequent thickening caused by blending with functional emulsion.

[0071] (IV) Organic-inorganic composite emulsions provide Class A flame-retardant inorganic properties and antibacterial and antiviral properties at the same time. There is no need to add additional antibacterial and antiviral additives, and it is non-biocidal and more healthy and environmentally friendly. At the same time, the microporous structure produced by hybridization can improve the hiding performance, effectively save the amount of titanium dioxide, and reduce resource / energy consumption.

[0072] The blending of pigments and fillers and the synergistic effect of organic-inorganic composite emulsions improve the thermal stability, crack resistance and scrub resistance of the system. DETAILED DESCRIPTION

[0073] In order to make the application, technical scheme and advantages of the present invention more clear, the present invention is described in detail in conjunction with specific embodiments. It should be understood that the embodiments are only used to illustrate the present invention, but not to limit the protection scope of the present invention. All simple improvements to the preparation method of the present invention under the premise of the concept of the present invention belong to the protection scope of the present invention.

[0074] Example 1

[0075] A method for preparing multifunctional inorganic coating

[0076] It includes the following components by weight:

[0077] 10-50 parts of water, 0.4-0.8 parts of thickener, 0.1-0.5 parts of pH regulator, 0.5-1 parts of defoamer, 0.2-1 parts of dispersant, 0.2-1 parts of wetting agent, 5-15 parts of calcined kaolin, 3-8 parts of diatomaceous earth, 10-18 parts of titanium dioxide, 10-20 parts of silicon micropowder, 13-30 parts of the organic-inorganic composite emulsion prepared in claim 1, 1-10 parts of anti-formaldehyde emulsion, 0.1-1 parts of anti-formaldehyde additive, and 0.1-2 parts of film-forming additive.

[0078] It comprises the following preparation steps:

[0079] s1. Add water to the container and stir at a stirring speed of 300 to 500 rpm; add thickener, pH adjuster, dispersant, wetting agent, one-third amount of defoamer, anti-formaldehyde additive to the water in sequence and stir at a stirring speed of 700 to 900 rpm for 3 ± 1 minutes;

[0080] s2. Add the pigment filler to the mixture of step s1 and stir at a stirring speed of 1200 to 1800 rpm for 20 ± 5 minutes;

[0081] s3. After the stirring in step s2 is completed, the stirring speed is modulated to 700 to 900 rpm, and the organic-inorganic composite emulsion, anti-formaldehyde emulsion, and film-forming agent prepared previously are sequentially added and stirred for 5 ± 2 minutes; the remaining portion of the defoamer is added and stirred for 20 ± 5 minutes, and stirring is continued to obtain the multifunctional inorganic coating;

[0082] The pigments and fillers are calcined kaolin, diatomaceous earth, titanium dioxide and silicon powder.

[0083] The thickener is hydroxyethyl cellulose;

[0084] The pH regulator is sodium hydroxide;

[0085] The defoaming agent is one or a combination of mineral oil defoaming agent and silicone defoaming agent;

[0086] The dispersant is a polycarboxylate anion type;

[0087] The wetting agent is isotridecyl polyethylene glycol ether;

[0088] The calcined kaolin has a particle size distribution shape of a book page structure, a hardness of 5 to 7, and an oil absorption of 60 to 80 g / 100 g;

[0089] The diatomite has a particle size distribution shape of a round sieve hollow column porous structure, a hardness of 5 to 7, an oil absorption of 100 to 130 g / 100 g, and SiO 2 Content 60~90%;

[0090] The titanium dioxide has a spherical particle size distribution, a hardness of 5 to 7, and an oil absorption of 18 to 25 g / 100 g.

[0091] The particle size distribution of the silicon micropowder is a needle-like structure, the particle size is 2.5 to 45 μm, the hardness is 6 to 8, the oil absorption is 20 to 26 g / 100 g, and the SiO 2 The content is over 99%.

[0092] The anti-formaldehyde emulsion is an anionic odorless styrene acrylic emulsion; the anti-formaldehyde auxiliary agent is trishydroxymethylaminomethane; the anti-formaldehyde auxiliary agent reacts with formaldehyde in a molar ratio of 1:2;

[0093] The film-forming aid is the isomer of alcohol ester hexadecene, 2,4,4-trimethylpentane-1,3-diylbis(2-methylpropionate).

[0094] Table 1 Composition parameters of each formulation group in Example 1 and each formulation group in the comparative example

[0095]

[0096]

[0097] Performance test execution standards:

[0098] The flame retardant performance test is carried out in accordance with the technical indicators and test methods in GB 8624-2012 "Classification of Combustion Performance of Building Materials and Products"; the antiviral performance test is based on T / CNCIA 01014-2020 "Antibacterial and Antiviral Coatings"; the antibacterial test is based on GB / T 21866-2008 "Determination of Antibacterial Properties and Antibacterial Effects of Antibacterial Coatings (Paint Films)"; the basic performance tests of thermal storage stability and contrast ratio are based on the technical indicators and test methods in GB / T 9756-2018 "Synthetic Resin Emulsion Interior Wall Coatings".

[0099] Table 2 Performance of each formulation group in Example 1 and each formulation group in the comparative example

[0100]

[0101] Table 3 Basic properties of each formulation group in Example 1 and each formulation group in the comparative example

[0102]

[0103]

[0104] As can be seen from Table 2, the antiviral effect of 1#~2# in Example 1 on EV71 and H3N2 reaches more than 95%, which is better than Comparative Example 3. The organic-inorganic composite emulsion has excellent antiviral performance. The antiviral function of the present invention is imparted by the prepared organic-inorganic composite emulsion, and no additional antiviral functional additives are required, which reduces the biocidal hazards caused by antiviral additives and is more healthy and environmentally friendly; the formaldehyde purification efficiency and formaldehyde purification durability of 1#~2# in Example 1 are better than Comparative Examples 1~3, and the anti-formaldehyde emulsion and anti Compared with the single use of emulsion or additive, the compounding of formaldehyde additives can provide better anti-formaldehyde performance. The perfect combination of anti-formaldehyde emulsion and anti-formaldehyde additives successfully achieves the goal of removing free formaldehyde pollutants in the environment by target anchoring. At the same time, from the comparison between Example 1# and Example 2#, it can be seen that in the system of compounding anti-formaldehyde emulsion and anti-formaldehyde additive, increasing the amount of anti-formaldehyde additive can more effectively improve the formaldehyde purification durability, because the anti-formaldehyde additive can migrate to the surface of the coating and fully contact with formaldehyde in the air, thereby improving the formaldehyde purification efficiency and formaldehyde purification durability.

[0105] As can be seen from Table 3, the increase in the hot storage viscosity of 1# to 2# in Example 1 is much lower than that of Comparative Example 3. The coating prepared by the organic-inorganic composite emulsion of the present invention has better storage stability than traditional inorganic coatings. The present invention designs the molecular chain structure in the organic emulsion through active controllable technology, so that the alkali metal silicate and the emulsion molecular chain are combined by chemical bonds to achieve a higher anchoring effect, and the organic and inorganic components interact with each other to achieve better stability, thereby improving the problem of poor storage stability of the existing inorganic coating system; the contrast ratio of Example 2# is higher than that of Comparative Examples 1 to 3. When the same titanium dioxide is added, increasing the amount of organic-inorganic composite emulsion can effectively increase the contrast ratio, because the organic-inorganic composite emulsion produces more microporous structures through hybridization, which can improve dry covering by changing the light reflection index, reduce the amount of titanium dioxide, and reduce energy consumption.

[0106] Example 2

[0107] A method for preparing an organic-inorganic composite emulsion, comprising the following components in parts by weight:

[0108] 8 parts of styrene monomer, 4 parts of butyl acrylate monomer, 2 parts of butyl methacrylate monomer, 2 parts of acrylic acid monomer, 1.2 parts of ammonium persulfate, 1.2 parts of sodium lauryl sulfate, 3 parts of sodium lignin sulfonate, 22.4 parts of potassium silicate, 8 parts of sodium silicate, 48.2 parts of deionized water;

[0109] The inorganic component and the organic component are polymerized by an in-situ polymerization method at a mass ratio of 1.9:1 at 75 to 85°C;

[0110] It states:

[0111] The organic components include: styrene monomer, butyl acrylate monomer, butyl methacrylate monomer, acrylic acid monomer;

[0112] Inorganic components include potassium silicate and sodium silicate;

[0113] It comprises the following preparation steps:

[0114] S1. Synthesis of core material:

[0115] Weigh a certain amount of sodium lignin sulfonate and add it to an appropriate amount of deionized water, stir it with a magnetic stirrer for 30 minutes to make it evenly mixed, add potassium silicate and sodium silicate dissolved in an appropriate amount of deionized water, stir it at 8000 rpm / min for 5 minutes to make it evenly mixed, and obtain the core material;

[0116] S2. Synthesis of wall materials and microencapsulation process:

[0117] Add styrene monomer, butyl acrylate monomer, butyl methacrylate monomer, acrylic acid monomer and the core material prepared in step S1 to an appropriate amount of deionized water, stir magnetically for 30 minutes to mix them evenly, heat the water bath to 75-80° C., inject ammonium persulfate dissolved in 10 ml of deionized water within 0.5 h using a syringe, and after the injection of ammonium persulfate, inject sodium dodecyl sulfate in the same manner, and finally react in a constant temperature water bath at 80-85° C. for 3-4 hours to obtain an organic-inorganic composite emulsion in the form of microcapsules.

[0118] The modulus of the potassium silicate is 3.9±0.2;

[0119] The modulus of sodium silicate is 3.2±0.2.

[0120] The organic-inorganic composite emulsion prepared in this embodiment has the following performance parameters:

[0121] Solid content: 25-60%;

[0122] pH: 10.5~11.5;

[0123] Tg: 5~25℃.

[0124] Comparative Examples 1# to 2# are prepared in the same manner as Example 2, and have the same basic composition. The main difference is the selection of raw materials for the core material synthesis in Table 4. For details, see Table 4.

[0125] Table 4 Composition parameters of each formulation in Example 2 and Comparative Examples 1 and 2

[0126]

[0127]

[0128] Performance testing method:

[0129] The surface morphology of the microcapsules was observed using a HITACHI S-3400N scanning electron microscope; the particle size distribution of the microcapsules was measured using a Malvern Nano Pro laser particle size analyzer; and the heat resistance of the microcapsules was measured using a SII TG / DTA 6200 thermogravimetric-differential thermal analyzer.

[0130] Table 5 Performance of each formulation group in Example 2 and Comparative Examples 1# and 2#

[0131]

[0132] As can be seen from Table 5, the comparative test of Example 2 with Comparative Examples 1# and 2# found that the microcapsules using sodium lignin sulfonate as the raw material for core material synthesis have better morphology, while the microcapsules prepared by using ordinary emulsifiers will have different degrees of depression and damage, and the microcapsules prepared without using emulsifiers will have a large number of damages, indicating that the addition of sodium lignin sulfonate can well regulate the morphology of microcapsules, and the particle size distribution of the microcapsules with the addition of sodium lignin sulfonate is concentrated; the thermal stability of Example 2 was compared with Comparative Examples 1# and 2# and found that the weight loss temperature of the microcapsule core material prepared by adding sodium lignin sulfonate was higher than that of the microcapsule core material prepared by conventional emulsifiers and without using emulsifiers; at the same temperature, the mass loss of the microcapsules prepared by adding sodium lignin sulfonate was lower than that of the microcapsules prepared by conventional emulsifiers and without using emulsifiers, indicating that the addition of sodium lignin sulfonate helps to improve the thermal stability of the emulsion, because sodium lignin sulfonate has a long hydrophobic skeleton and abundant hydrophilic side chains, has amphiphilicity, is used to stabilize potassium silicate and sodium silicate, and improves stability.

[0133] To sum up, the above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the disclosed technical content are regarded as equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

[0134] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0135] The experimental methods without specific conditions in the present invention are usually carried out under conventional conditions or conditions recommended by the manufacturer.

[0136] Unless otherwise stated, the various optimization technical solutions in the present invention can be combined with each other.

[0137] Unless otherwise indicated, percentages and parts are by weight.

[0138] Experimental methods without specific conditions specified in the instructions and examples are usually carried out under conventional conditions or conditions recommended by the manufacturers.

[0139] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any method and material similar or equivalent to the described content can be applied to the method of the present invention.

Claims

1. A method for preparing an organic-inorganic composite emulsion, Features: It includes the following components by weight: 1-20 parts of styrene monomer, 1-12 parts of butyl acrylate monomer, 1-8 parts of butyl methacrylate monomer, 1-8 parts of acrylic acid monomer, 1-2 parts of ammonium persulfate, 1-2 parts of sodium dodecyl sulfate, 1-4 parts of sodium lignin sulfonate, 10-40 parts of potassium silicate, 1-20 parts of sodium silicate, and 30-60 parts of deionized water; The inorganic component and the organic component are polymerized by an in-situ polymerization method at a mass ratio of 1.7 to 2:1 at 75 to 85°C; It states: The organic components include: styrene monomer, butyl acrylate monomer, butyl methacrylate monomer, acrylic acid monomer; Inorganic components include potassium silicate and sodium silicate; It comprises the following preparation steps: S1. Synthesis of core material: Weigh a certain amount of sodium lignin sulfonate and add it to an appropriate amount of deionized water, stir it with a magnetic force for 30 minutes to make it evenly mixed, add potassium silicate and sodium silicate dissolved in an appropriate amount of deionized water, stir it at 8000 rpm / min for 5 minutes to make it evenly mixed, and obtain the core material; S2. Synthesis of wall materials and microencapsulation process: Add styrene monomer, butyl acrylate monomer, butyl methacrylate monomer, acrylic acid monomer and the core material prepared in step S1 to an appropriate amount of deionized water, stir magnetically for 30 minutes to mix them evenly, heat the water bath to 75-80° C., inject ammonium persulfate dissolved in 10 ml of deionized water within 0.5 h using a syringe, and after the injection of ammonium persulfate, inject sodium dodecyl sulfate in the same manner, and finally react in a constant temperature water bath at 80-85° C. for 3-4 hours to obtain an organic-inorganic composite emulsion in the form of microcapsules.

2. The method for preparing the organic-inorganic composite emulsion according to claim 1, Features: The modulus of the potassium silicate is 3.9±0.2; The modulus of sodium silicate is 3.2±0.

2.

3. The method for preparing the organic-inorganic composite emulsion according to claim 1, Features: The organic-inorganic composite emulsion has the following performance parameters: Solid content: 25-60%; pH: 10.5~11.5; Tg: 5~25℃.

4. An organic-inorganic composite emulsion, Features: The invention is prepared according to the preparation method according to any one of claims 1 to 3.

5. A multifunctional inorganic coating, Features: It includes the following components by weight: 10-50 parts of water, 0.4-0.8 parts of thickener, 0.1-0.5 parts of pH regulator, 0.5-1 parts of defoamer, 0.2-1 parts of dispersant, 0.2-1 parts of wetting agent, 5-15 parts of calcined kaolin, 3-8 parts of diatomaceous earth, 10-18 parts of titanium dioxide, 10-20 parts of silicon powder, 13-30 parts of the organic-inorganic composite emulsion prepared according to claim 1, 1-10 parts of anti-formaldehyde emulsion, 0.1-1 parts of anti-formaldehyde auxiliary agent, and 0.1-2 parts of film-forming auxiliary agent.

6. The multifunctional inorganic coating according to claim 5, Features: It includes one or more of the following characteristics: The thickener is one or a combination of hydroxyethyl cellulose, bio-gum, and modified bentonite; The pH regulator is one or a combination of sodium hydroxide, organic alcohol ammonia, and organic amine pH regulators; The defoaming agent is one or a combination of mineral oil defoaming agent and silicone defoaming agent; The dispersant is one or a combination of polycarboxylic acid anion type and polyoxyethylene alkyl ether type; The wetting agent is one or a combination of isotridecyl polyethylene glycol ethers, fatty alcohols, and nonionic surfactants; The calcined kaolin has a particle size distribution shape of a book page structure, a hardness of 5 to 7, and an oil absorption of 60 to 80 g / 100 g; The diatomite has a particle size distribution shape of a round sieve hollow column porous structure, a hardness of 5 to 7, an oil absorption of 100 to 130 g / 100 g, and SiO 2 Content 60~90%; The titanium dioxide has a spherical particle size distribution, a hardness of 5 to 7, and an oil absorption of 18 to 25 g / 100 g. The particle size distribution of the silicon micropowder is a needle-like structure, the particle size is 2.5 to 45 μm, the hardness is 6 to 8, the oil absorption is 20 to 26 g / 100 g, and the SiO 2 The content is over 99%.

7. The multifunctional inorganic coating according to claim 5, Features: The anti-formaldehyde emulsion is an anionic odorless styrene acrylic emulsion; the anti-formaldehyde auxiliary agent is trishydroxymethylaminomethane; the anti-formaldehyde auxiliary agent reacts with formaldehyde in a molar ratio of 1:

2.

8. The multifunctional inorganic coating according to claim 5, Features: The film-forming aid is the isomer of alcohol ester hexadecene, 2,4,4-trimethylpentane-1,3-diylbis(2-methylpropionate).

9. A method for preparing the multifunctional inorganic coating according to any one of claims 5 to 7, Features: It comprises the following preparation steps: s1. Add water to the container and stir at a stirring speed of 300 to 500 rpm; add thickener, pH adjuster, dispersant, wetting agent, one-third amount of defoamer, anti-formaldehyde additive to the water in sequence and stir at a stirring speed of 700 to 900 rpm for 3 ± 1 minutes; s2. Add the pigment filler to the mixture of step s1 and stir at a stirring speed of 1200 to 1800 rpm for 20 ± 5 minutes; s3. After the stirring in step s2 is completed, the stirring speed is modulated to 700 to 900 rpm, and the organic-inorganic composite emulsion, the anti-formaldehyde emulsion, and the film-forming aid prepared according to claim 1 are sequentially added and stirred for 5 ± 2 minutes; the remaining portion of the defoamer is added and stirred for 20 ± 5 minutes, and stirring is continued to obtain the multifunctional inorganic coating; The pigments and fillers are calcined kaolin, diatomaceous earth, titanium dioxide and silicon powder.

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