Diatom ooze dry powder coating and preparation method thereof

A kind of diatom mud dry powder coating and its preparation methodTechnical field

[0001] The present invention relates to the technical field of building decoration materials, in particular to a diatom mud coating and a preparation method thereof.

Background technique

[0002] Diatom mud paint is a functional wall material with diatomaceous earth as the main component. It is made of diatomite ore after calcining and grinding, adding aggregates, anti-cracking fibers, fillers and binders. Forming. Because diatomaceous earth has a microporous structure, its porosity is as high as 90% or more. This structure has good adsorption performance, can purify the air, and has the effects of fire and flame retardant, sound absorption and noise reduction. Therefore, it is used as wallpaper and latex paint. As an alternative product, diatom mud paint is being widely used in interior wall decoration of villas, hotels, homes and other buildings.

[0003] At present, most building decoration materials and furniture release formaldehyde, benzene, ammonia and other substances that are extremely harmful to the human body. These pollutants cannot be effectively removed by opening windows for ventilation and placing adsorbents. The existing diatom mud products are formulated with nano-holmium dioxide. Because of its good photocatalytic activity, it can decompose and eliminate pollutants such as formaldehyde under ultraviolet radiation. However, nano-titanium dioxide as a photocatalyst can only decompose harmful substances when exposed to sunlight. When diatom mud paint is used indoors, there is little opportunity for sunlight to be exposed, and it cannot effectively play the decomposing effect of photocatalyst; and formaldehyde After being absorbed by the diatom mud paint, other harmful substances will accumulate in the voids of the diatom mud and become a new source of pollution. Therefore, the development of a new type of decoration material to eliminate indoor pollution has become an urgent topic.

Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a diatom mud dry powder coating and a preparation method thereof. After the coating is used, it can quickly absorb and remove indoor formaldehyde and other volatile organic pollutants, and It maintains the long-lasting removal ability, has the characteristics of good indoor purification effect and wide application.

[0005] The technical problem of the present invention is achieved by the following technical solutions:

[0006] A kind of diatom mud dry powder coating, the coating is prepared from the following raw materials in parts by mass: 10-35 parts of composite diatomaceous earth, 10-30 parts of talc, and 10-40 parts of heavy bait powder , 15-50 parts of shoulder clay, 2-9 parts of polyvinyl alcohol powder (PVA), 10-25 parts of redispersible rubber powder, 0.6-1.5 parts of cellulose ether, 5-10 parts of titanium dioxide.

[0007] The above-mentioned diatom mud dry powder coating, the composite diatomaceous earth includes diatomaceous earth and an active aldehyde remover, the active aldehyde remover is nano-sized titanium dioxide phosphate, and the addition ratio of diatomaceous earth and nano-sized titanium dioxide phosphate is 30- 200:1.

[0008] The above-mentioned diatom mud dry powder coating, the coating further includes a negative oxygen ion releasing agent, the negative oxygen ion releasing agent is iron oxide or zinc oxide loaded with infrared visible light photocatalyst, and the amount of the negative oxygen ion releasing agent is 3 -5 copies.

[0009] The above-mentioned diatom mud dry powder coating, the redispersible rubber powder includes one or a mixture of polyacrylate copolymer and ethylene-vinyl acetate copolymer.

[0010] The above-mentioned diatom mud dry powder coating, the coating is formulated with the following raw materials in parts by mass: 20 parts of diatomaceous earth, 0.3 parts of nano-scale titanium dioxide, 18 parts of talc powder, 20 parts of heavy calcium powder, 25 parts of kaolin, 5 parts of PVA rubber powder, 15 parts of redispersible rubber powder, 1.2 parts of cellulose ether, 8 parts of titanium dioxide, 4 parts of negative oxygen ion release agent.

[0011] The preparation method of the above-mentioned diatom mud dry powder coating includes the following steps:

[0012] _a.Add nano-scale titanium dioxide phosphate to deionized water, add dispersant, and ultrasonically disperse for 30-40 minutes,

Prepare nano-phosphate titanium dioxide solution;

[0013] b. Disperse diatomaceous earth in deionized water, add nano phosphate titanium dioxide solution dropwise while stirring in a high-speed disperser, continue to stir for 2-3 hours after the addition, to form a uniform slurry, and put it into the drying box It is dried into powder to make composite diatomaceous earth;

[0014] c. In the dry powder mixer, add the raw materials such as talc powder, heavy calcium powder and kaolin in the formula, and then add the composite diatomaceous earth obtained in step b, and stir until mixed uniformly to obtain a diatom mud dry powder coating.

[0015] The preparation method of the above-mentioned diatom mud dry powder coating, the dispersant is sodium butyl naphthalene sulfonate or sodium methylene naphthalene sulfonate, and the addition amount of the dispersant is 0.1%-0.3% of the mass of nano-scale titanium dioxide phosphate .

[0016] The present invention utilizes the porous adsorption effect of diatomaceous earth to adsorb volatile organic pollutants into the voids, and decompose and remove harmful gases such as formaldehyde through the non-photocatalyst-active aldehyde remover in the voids. The diatomite is highly efficient The adsorption and active aldehyde remover decomposes and removes formaldehyde. The two cooperate with each other and have complementary functions, which increase the contact probability of the active aldehyde remover with organic pollutants and improve the removal efficiency. It avoids the problem that the photocatalyst needs visible or even ultraviolet light to degrade harmful substances, and has the advantages of high purification efficiency and long-lasting removal efficiency. Therefore, the coating is more suitable for use in the room and has a wide range of application prospects.

[0017] The present invention instantly absorbs and removes harmful gases such as indoor formaldehyde, TVOC, etc. after use, has a fast purification speed, and has the advantages of zero waiting, that is, just brush and live. After testing, it can instantly remove formaldehyde in the area near the wall, with a removal rate of up to 100%. At the same time, it can achieve long-term adsorption and decomposition of harmful gases such as formaldehyde. After 24 hours, the removal rate of formaldehyde in the room can reach more than 99%. It not only saves the time from decoration to check-in, but also the indoor environment is friendly and clean. It is a truly green and environmentally friendly functional coating that can quickly remove harmful gases such as formaldehyde.

[0018] The present invention is a dry powder paint, which is used after adding water on site during construction. Therefore, unlike traditional paints or latex paints, organic solvents and polymer emulsions and other organic additives need to be added; transportation is convenient, environmentally friendly and safe. In terms of simple construction, it can be sprayed or rolled.

[0019] The negative ion release agent contained in the present invention can release negatively charged ions, which can improve human immunity and promote metabolism. At the same time, negative ions can kill harmful bacteria and further improve the cleanliness of the surrounding environment.

Detailed ways

[0020] The present invention will be further described in detail below in conjunction with the embodiments.

[0021] The present invention is formulated with the following components in parts by mass:

[0022] 10-35 parts of composite diatomite, 10-30 parts of talc, 10-40 parts of heavy calcium powder, 15-50 parts of kaolin, 2-9 parts of polyvinyl alcohol powder (PVA), 10 parts of redispersible rubber powder -25 parts, 0.6-1.5 parts of cellulose ether, 5-10 parts of titanium dioxide.

[0023] The composite diatomaceous earth includes diatomaceous earth and an active aldehyde removal agent, and the addition ratio of the diatomaceous earth and the active aldehyde removal agent is 30-200:1 (v/v). The fineness of diatomaceous earth is 300-400 mesh, the active aldehyde scavenger is nano-sized titanium dioxide phosphate, and the particle size is preferably 1-10 nanometers. Titanium dioxide phosphate is a nano-level active substance, which can activate the oxygen in the air to produce strong oxidizing hydroxyl radicals, and decompose harmful substances in the air, such as formaldehyde and benzene series, into harmless carbon dioxide, water and other harmless substances. Unlike conventional nano-scale titanium dioxide that requires ultraviolet light to produce activity, nano-scale titanium dioxide phosphate is still environmentally friendly in environments such as basements where the light is weak or not exposed to the sun. It continues to remove harmful substances such as formaldehyde and keeps the room for a long time. Purification. Since nano-sized titanium dioxide phosphate is activated by contact with oxygen and is easily deactivated when exposed to the air for a long time, it is necessary to embed the titanium dioxide in the micropores of diatomaceous earth to form composite diatomaceous earth during the production process to effectively maintain its activity.

[0024] The fineness of the heavy calcium powder is 800 mesh, and the calcium carbonate content is greater than 75%. The fineness of talc is 800 mesh. Talcum powder and heavy calcium powder as inorganic fillers can effectively improve the strength of diatom mud paint. The fineness of kaolin is 1200 mesh, which can improve the plasticity of the coating and enhance the decorative effect after modeling.

[0025] The redispersible rubber powder is a water-soluble redispersible rubber powder, which includes one or a mixture of polyacrylate copolymers and ethylene-vinyl acetate copolymers.

[0026] Cellulose ethers include HPMC (Light Propyl Methyl Cellulose) and HEC (Light Ethyl Cellulose), and the combination of the two celluloses can provide viscosity under different shearing forces.

[0027] A negative oxygen ion release agent is also added to the formula of the diatom mud dry powder coating. The formula is: 15-30 parts of composite diatomaceous earth, 15-25 parts of talc, 10-30 parts of heavy calcium powder, and 20-40 parts of kaolin. Parts, 3-6 parts of polyvinyl alcohol rubber powder (PVA), 10-20 parts of redispersible rubber powder, 1.0-1.5 parts of cellulose ether, 5-10 parts of titanium dioxide, 3-5 parts of negative oxygen ion release agent.

[0028] The preferred formula is: 20 parts of diatomaceous earth, 0.3 parts of nano-sized titanium dioxide phosphate, 18 parts of talc powder, 20 parts of heavy calcium powder, 25 parts of kaolin, 5 parts of PVA rubber powder, 15 parts of redispersible rubber powder, 1.2 parts of cellulose ether, 8 parts of titanium dioxide, 4 parts of negative oxygen ion release agent.

[0029] The negative oxygen ion release agent is iron oxide or zinc oxide loaded with infrared visible light photocatalyst, and inorganic oxides such as iron oxide or zinc oxide are used as the carrier of infrared visible light photocatalyst, which can continuously release negative oxygen ions under ordinary light. .

[0030] Composite diatomaceous earth and inorganic fillers, rubber powder, cellulose ether and other raw materials are compounded in a certain proportion, which enhances the adhesion and flexibility of diatom mud, improves the overall performance of the coating, and avoids glue After the powder and cellulose ether are added in a certain proportion, the porous structure of the diatomite is sealed to ensure its adsorption of formaldehyde.

[0031] The preparation method of the above-mentioned diatom mud dry powder coating is carried out according to the following steps:

[0032] a. Add nano-sized titanium dioxide phosphate to deionized water, add a dispersant, and ultrasonically disperse for 30-40 minutes to prepare a nano-sized titanium dioxide phosphate solution;

[0033] The dispersant is sodium butyl naphthalene sulfonate or sodium methylene naphthalene sulfonate; the added amount of the dispersant is 0.1%-0.3% of the mass of nano-scale titanium dioxide phosphate.

[0034] b. Disperse diatomaceous earth in deionized water, add nano phosphate titanium dioxide solution dropwise while stirring in a high-speed disperser, continue to stir for 2-3 hours after the addition, to form a uniform slurry, and put it into the drying box The medium is dried into a powder, at this time the nano-TiO2 phosphate is embedded in the voids of the diatomaceous earth to form an active composite diatomaceous earth;

[0035] Nano titanium dioxide phosphate has a large specific surface area, which is easy to spontaneously form agglomerates, which is inconvenient to use. Adding a dispersant can make the nanometer phosphate dioxide uniformly distributed in the diatomite pores, which is beneficial to improve the dispersion of nanometer phosphate dioxide in the diatomaceous earth. Sex and stability.

[0036] c. Add raw materials such as talc, heavy calcium powder and kaolin in the dry powder mixer, and then add the composite diatomaceous earth obtained in step b, and stir until the mixture is uniform to obtain a diatom mud dry powder coating product.

[0037] Embodiment

[0038] The mass parts of each component in the formula for preparing diatom mud dry powder coatings are shown in Table 1.

[0039] Table 1 The proportions of the components of the diatom mud dry powder coating in the embodiment

[0040]

<td></td><td>Example 1</td><td>Example 2</td><td>Example 3</td><td>Example 4</td>

<td>diatomite</td><td>20</td><td>15</td><td>30</td><td>25</td>

<td>Titanium Dioxide Phosphate</td><td>0.3</td><td>0.1</td><td>0.8</td><td>0.6</td>

<td>talcum powder</td><td>18</td><td>10</td><td>25</td><td>12</td>

<td>Heavy calcium powder</td><td>20</td><td>18</td><td>35</td><td>30</td>

<td>Kaolin</td><td>25</td><td>20</td><td>50</td><td>45</td>

<td>Polyvinyl Alcohol Powder</td><td>5</td><td>2</td><td>6</td><td>8</td>

<td>Redispersible rubber powder</td><td>15</td><td>12</td><td>20</td><td>25</td>

<td>Cellulose ether</td><td>1.2</td><td>0.8</td><td>1.5</td><td>1.0</td>

<td>Titanium Dioxide</td><td>8</td><td>5</td><td>9</td><td>6</td>

<td>Negative oxygen ion release agent</td><td>4</td><td>3</td><td>5</td><td>0</td>

Example 1

[0042] The preparation method of diatom mud dry powder coating is:

[0043] Add 0.3kg of nanometer phosphate titanium dioxide to 1L of deionized water, add 0.6g of sodium butyl naphthalene sulfonate, and ultrasonically disperse for 30 minutes to prepare a nanometer phosphate titanium dioxide solution. Add 20kg of diatomaceous earth and 30L of deionized water to the high-speed disperser for dispersion, then add the nano phosphate titanium dioxide solution dropwise while stirring, and continue to stir for 2 hours after the addition is complete to form a uniform slurry, which is dried into a powder in a drying box , Made of composite diatomaceous earth.

[00⁴⁴] Take 18kg talc powder, 20kg heavy bait powder, 25kg kaolin, 5kg PVA rubber powder, 10kg polypropylene rubber powder, 5kg ethylene-vinyl acetate rubber powder, 0.6kg HPMC, 0.6kg HEC, 8kg titanium dioxide and 4kg The oxygen ion release agent is added to the dry powder mixer, and then the prepared composite diatomaceous earth is added, and the mixture is fully stirred for 1 hour until the mixture is uniform, and the diatom mud dry powder coating product, namely sample 1, is obtained.

[0045] Place the lkg sample 1 in a sealed box and spread it out, and test it with a negative oxygen ion detector after 3 hours. The test result is 4632/m³。

Example 2

[0047] The preparation method of diatom mud dry powder coating is:

[0048] 0.1kg of nano phosphate titanium dioxide was added to 0.5L of deionized water, 0.3g of sodium methylene naphthalene sulfonate was added, and ultrasonic dispersion was performed for 40 minutes to prepare a nano phosphate solution of titanium dioxide. Add 15kg of diatomaceous earth and 25L of deionized water into a high-speed disperser to disperse. Add the nano phosphate titanium dioxide solution dropwise while stirring. After the dropwise addition, continue to stir for 2.5 hours to form a uniform slurry, which will be dried into a powder in a drying box. Make composite diatomaceous earth. Combine 10kg talc powder, 18kg heavy calcium powder, 20kg kaolin, 2kg PVA rubber powder, 6kg polypropionate rubber powder, 6kg ethylene-vinyl acetate rubber powder, 0.4kg HPMC, 0.4kg HEC, 5kg white powder and 3kg The negative oxygen ion release agent is added to the dry powder mixer, the composite diatomaceous earth is added, and the mixture is stirred for 1.5 hours until the mixture is uniform, to obtain the diatom mud dry powder coating product, namely sample 2.

[0049] The method of Example 1 was used to detect the content of negative oxygen ions, and the detection result was 3768/m³。

Example 3

[00511 The preparation method of diatom mud dry powder paint is:

[0052] Add 0.8kg of nanometer phosphate titanium dioxide to 1.5L of deionized water, add 1.0g of sodium methylene naphthalene sulfonate, and ultrasonically disperse for 35 minutes to prepare a nanometer phosphate titanium dioxide solution. Add 30kg of diatomaceous earth and 45L of deionized water to a high-speed disperser for dispersion, add the nano phosphate titanium dioxide solution dropwise while stirring, continue to stir for 3 hours after the dropwise addition, to form a uniform slurry, and put it into a drying box to dry into a powder. Make composite diatomaceous earth. Add 25kg talc powder, 35kg heavy calcium powder, 50kg kaolin, 6kg PVA powder, 20kg ethylene-vinyl acetate powder, 0.8kg HPMC, 0.8kg HEC, 9kg titanium dioxide and 5kg negative oxygen ion release agent into the dry powder mixer , Then add the composite diatomaceous earth and stir for 2 hours to obtain the diatom mud dry powder coating product, namely sample 3.

[0053] The method of Example 1 was used to detect the content of negative oxygen ions, and the detection result was 5563/m³。

Example 4

[0055] According to the raw material ratio in Table 1 and the method of Example 1, the diatom mud dry powder coating was prepared, and the content of negative oxygen ions was detected by the method of Example 1. The detection result was 12 pcs/m³。

[0056] Effect example of formaldehyde removal test

[0057] Sample 1: Take the diatom mud paint 1kg prepared in Example 1, add 1.8 kg of water according to the mass ratio of 1:1.8, stir it into mud, and apply it flat on the test board with a coating thickness of 2.5mm, natural Air dry. Samples 2 and 3 take the diatom mud paint of Examples 2 and 3, and the preparation process is the same as that of product 1.

[0058] Reference substance: Nano-titanium dioxide is used to replace nano-titanium dioxide phosphate, and the remaining materials and preparation methods are the same as in Example 1. The prepared titanium dioxide diatom mud paint is made into a paint test panel according to the above steps.

[0059] Test procedure: The test was carried out in a closed test box, and a formaldehyde analyzer was placed in the box. Put in a cotton ball that has absorbed the same volume of formalin, and put it into the coating test panel coated with the sample or control after W minutes, and start timing. Measure and record the residual content of formaldehyde according to a certain period of time. The test results are shown in Table 2.

[0060] Table 2 Test results of removal of formaldehyde by different diatom mud coatings, unit mg/m³

[0061]

<td></td><td>The initial concentration</td><td>1 minute</td><td>1 hour</td><td>24 hours</td><td>48 hours</td><td>48 hours removal rate</td>

<td>Sample 1</td><td>1.32</td><td>0.20</td><td>0.15</td><td>0.01</td><td>0.00</td><td>100%</td>

<td>Sample 2</td><td>1.25</td><td>0.36</td><td>0.22</td><td>0.04</td><td>0.01</td><td>99.2%</td>

<td>Sample 3</td><td>1.28</td><td>0.15</td><td>0.07</td><td>0.01</td><td>0.00</td><td>100%</td>

<td>Reference substance</td><td>1.30</td><td>0.85</td><td>0.69</td><td>0.56</td><td>0.42</td><td>67.7%</td>

<td>Reference substance + UV irradiation</td><td>1.36</td><td>0.63</td><td>0.43</td><td>0.31</td><td>0.23</td><td>83%</td>

[0062] As can be seen from the above table, the 1 day and 2 days of the three examples of the present invention have a formaldehyde removal effect of more than 99%, which is much higher than the formaldehyde removal rate of the reference product in the absence of light irradiation. The formaldehyde removal rate is 17% higher than that of the reference product when exposed to ultraviolet rays. Therefore, the diatom mud dry powder coating containing the active dealdehyde agent has a better ability to remove formaldehyde and other harmful substances than the diatom mud coating containing the photocatalyst-nano-titanium dioxide .