CN102989436A - Coating with antibacterial and air-purifying functions - Google Patents

Abstract

The invention provides a coating with antibacterial and air-purifying functions. The coating is formed by the following component in percentage by mass: 1-10% of porous silicon dioxide and titanium dioxide compound photocatalytic material, 40-85% of calcium carbonate, 10-50% of ash calcium powder, 5-30% of talcum powder, 10-15% of white cement, 0.5-5% of organic polymer and 0.1-1% of cellulose. A dry powder coating and water are mixed according to a weight ratio of 1: (0.3-1) and then a mixture is subjected to common spraying or scraping construction to be cured into a film, so that the long-effect antibacterial and air-purifying effects are realized. The antibacterial effect on common bacteria in the indoor air, such as Escherichia coli, reaches to be more than 98%; more than 83% of formaldehyde can be decomposed and purified in 48 hours and more than 49% of toluene can be decomposed and purified; and compared with the similar products, the formaldehyde/toluene degradation capability of the coating is stronger, so that the coating can be used as an indoor coating.

Description

Coatings with antibacterial and air-purifying functions

technical field

The invention relates to the technical field of photocatalyst materials and the field of paint preparation, in particular to a paint with antibacterial and air purification functions.

Background technique

With the advancement of science and technology and the rapid development of modern industry, environmental problems are becoming more and more serious. Human beings pay more attention to health. With the gradual improvement of environmental protection awareness, the demand for functional environmental protection coatings is increasingly urgent. However, some harmful fungicides and other ingredients are often added to traditional paints, which can easily cause environmental pollution and greatly reduce the safety of paints.

As a new type of inorganic functional material, nano-titanium dioxide has the characteristics of acid and alkali resistance, light and chemical corrosion resistance, and can use the ultraviolet light contained in sunlight as an excitation light source to generate surface photogenerated holes with strong oxidation ability. Treatment, air purification, removal of petroleum pollutants, antibacterial, super hydrophilic anti-fog, etc. have been widely used, and the photocatalytic technology of nano-titanium dioxide has increasingly become a research hotspot at home and abroad. However, due to the extremely small particle size of nano-titanium dioxide, there are disadvantages such as difficult recovery and easy aggregation in wastewater and waste gas treatment, which seriously restricts its industrialization. Therefore, the preparation of supported nano-TiO photocatalysts has become an urgent problem to be solved.

Using specially prepared nano-titanium dioxide photocatalysts instead of traditional fungicides in home decoration coatings can not only play a role in sterilization and disinfection, but also improve the degradation efficiency of organic volatile substances.

Contents of the invention

The purpose of the present invention is to provide a novel coating with antibacterial and air purification functions.

In order to achieve the purpose of the present invention, the present invention firstly provides a composite photocatalytic material of porous silicon dioxide and titanium dioxide, the preparation method of which comprises the following steps: adding urea to the solution containing Ti ⁴⁺ , heating the urea solution to hydrolyze to generate NH ⁴⁺ and OH ^- , then the OH ^- in the solution combines with Ti ⁴⁺ to form TiO(OH) ₂ crystals, and the porous silica is used as the carrier to coat the TiO(OH) ₂ precipitated on the surface of the porous silica. After filtration, washing, drying, and calcination, the TiO ₂ obtained by decomposing TiO(OH) ₂ is more firmly combined on the surface of porous silica, and then anion powder is added to mix and disperse to obtain the product.

Wherein, the raw material of the porous silica is from one or more of diatomite, zeolite powder, synthetic silica and the like. Described anion powder is tourmaline powder etc.

The solution containing Ti ⁴⁺ can be prepared by dissolving titanium salt (such as titanium tetrachloride, titanyl sulfate or butyl titanate, etc.) in water.

The invention also provides the application of the composite photocatalytic material of porous silicon dioxide and titanium dioxide in the preparation of paint.

The present invention also provides a coating with antibacterial and air-purifying functions, the weight percent of each component is:

Wherein, the raw material of the organic polymer comes from dispersible latex powder and/or polyvinyl alcohol powder and the like.

The calcium carbonate is 250-800 mesh, the ash calcium powder is 400-800 mesh, and the talcum powder is 300-2500 mesh.

Mix the above raw materials in proportion and stir evenly to obtain the coating with antibacterial and air purification functions of the present invention. Mix the dry powder coating with water in a weight ratio of 1:0.3~1, stir evenly, and then pass through general spraying or scraping. After coating construction, it has long-term antibacterial and air purification effects after curing to form a film. The antibacterial effect against common bacteria in indoor air, such as Escherichia coli, can reach more than 98%. It can decompose and purify more than 83% of formaldehyde within 48 hours, and decompose and purify more than 49% of toluene. Compared with similar products, the ability to degrade formaldehyde/toluene Stronger and can be used as an interior paint.

Detailed ways

The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, and the raw materials used are all commercially available products.

Embodiment 1 Preparation of porous silicon dioxide and titanium dioxide composite photocatalytic material

Take 50 grams of porous silicon dioxide, 187 grams of urea, add 15000 ml of water, stir well, and add 15600 ml of water to 625 ml of 0.5 mol/L TiOSO ₄ solution, then mix and stir the two liquids, adjust the pH value to 1.5, and stir at 75 ° C 60mim, filtered, washed, dried at 150°C for 2 hours, calcined at 500°C for 2 hours, and then added 1 gram of tourmaline powder to mix and disperse to obtain a composite photocatalytic material of porous silica and titanium dioxide.

Wherein, the preparation method of the porous silica is as follows: take 200 grams of diatomite raw earth, wash it with water, take 100 grams of washed diatomite and calcinate it at 550° C. for 1.5 hours, and add 1.3% diatomite after cooling. 120ml of sulfuric acid was stirred evenly, and calcined at 250°C for 2.5 hours, then washed with iron remover, and then washed with water until the pH value was 7, filtered and dried to obtain porous silica.

Embodiment 2 Preparation of porous silicon dioxide and titanium dioxide composite photocatalytic material

Take 100 grams of porous silicon dioxide, 375 grams of urea, add 30,000 ml of water, stir well, and add 32,000 ml of water to 1250 ml of 0.5 mol/L TiOSO ₄ solution, then mix and stir the two liquids, adjust the pH value to 1.5, and stir at 75 ° C 90mim, filtered, washed, dried at 150°C for 2.5 hours, calcined at 650°C for 3 hours, and then added 2 grams of tourmaline powder to mix and disperse to obtain a composite photocatalytic material of porous silica and titanium dioxide.

Wherein, the preparation method of the porous silica is as follows: take 1000 grams of zeolite raw ore and pulverize it to 100 mesh, impregnate it with 3000 ml of hydrochloric acid or sulfuric acid with a concentration of 6-10%, filter it for 3 hours, and then wash it with distilled water until the pH value is 7. , The obtained zeolite precipitate is dried and calcined at 350-500°C to obtain porous silica.

The preparation of embodiment 3 porous silicon dioxide and titanium dioxide composite photocatalytic material

Get 50 grams of porous silicon dioxide and add 1500 ml of water and stir evenly; get another 100 ml of 2.9 mol/L _TiCl solution; React at 30°C for 2 hours, adjust the pH value to 4.5, filter, wash, dry at 105°C for 2 hours, calcine at 650°C for 3 hours, add 1 gram of tourmaline powder to mix and disperse, and the composite photocatalytic material of porous silica and titanium dioxide is obtained .

Wherein, the preparation method of the porous silica is as follows: take 1000 grams of kaolin or hard kaolin and pulverize to 80 meshes, then calcined at 500-600° C. for 2 hours, and then mix the calcined soil with 30% hydrochloric acid by 1 : Mixed at a weight ratio of 2.5, soaked in acid at 90°C for 7 hours, neutralized, filtered, and dried to obtain porous silica.

Embodiment 4 Preparation of porous silicon dioxide and titanium dioxide composite photocatalytic material

Get 100 grams of porous silicon dioxide and add 3000 ml of water and stir evenly; get another 2.9 mol/L TiCl ₄ solution 200 ml; React at 30°C for 2.5 hours, adjust the pH value to 4.2, filter, wash, dry at 105°C for 2 hours, calcine at 700°C for 4 hours, add 2 grams of tourmaline powder to mix and disperse, and the composite photocatalytic material of porous silica and titanium dioxide is obtained .

Wherein, the preparation method of the porous silica is as follows: take 200 grams of diatomite raw earth, wash it with water, take 100 grams of diatomite washed with water and calcinate it at 500 ° C for 2 hours, and add the concentration of 1.4% after cooling. 110ml of sulfuric acid was stirred evenly, calcined at 220°C for 3 hours, then washed with iron remover, and then washed with water until the pH value was 7, filtered and dried to obtain porous silica.

Embodiment 5 has the preparation of the coating of antibacterial and air purification function

Get the porous silicon dioxide and titanium dioxide composite photocatalytic material prepared in 10 grams of embodiment 1 or embodiment 4, 800 mesh calcium carbonate powder 275 grams, 800 mesh ash calcium powder 150 grams, 2500 mesh talcum powder 50 grams, white cement 25 grams gram, 5 grams of dispersible latex powder, 2.5 grams of cellulose, mix and stir evenly, obtain the coating with antibacterial and air purification function.

Embodiment 6 has the preparation of the coating of antibacterial and air purification function

Get the porous silicon dioxide and titanium dioxide composite photocatalyst material prepared in 20 grams of embodiment 2 or embodiment 3, 300 grams of 400 mesh calcium carbonate powder, 150 grams of 600 mesh ash calcium powder, 50 grams of 1000 mesh talc powder, 25 grams of white cement gram, 6 grams of polyvinyl alcohol powder, 3 grams of cellulose, mix and stir evenly, promptly get the coating with antibacterial and air purification function.

Embodiment 7 Application of coating of the present invention in sterilization and indoor air purification

The coating with antibacterial and air purification functions of the present invention is mainly used for indoor decomposition, purification of harmful gases such as formaldehyde and toluene, and removal of peculiar smells in the air. Indoor wall per square meter with 500 grams of antibacterial and air-purifying functional coatings prepared in Example 5 or Example 6, add 200 grams of water and stir evenly, and then apply and scrape on the top layer. After drying, in the absence of sunlight or light, the The coating can absorb indoor formaldehyde, toluene and peculiar smell, and the antibacterial effect on common bacteria in indoor air, such as Escherichia coli, can reach more than 98%. After 48 hours of sunlight or lighting, the decomposition and purification of formaldehyde can reach more than 83%. (National standard qualified ≥ 75%), decomposes and purifies more than 49% of toluene (national standard qualified ≥ 35%), and has a persistent decomposition function, and also has the function of releasing negative oxygen ions.

The invention solves the disadvantages of diatom mud preparation, such as large dosage, difficult construction, rough surface, high cost, poor water resistance, and low functional efficiency in decomposing and purifying harmful gases such as formaldehyde and toluene in indoor air. The antibacterial and air-purifying functional coating of the present invention improves the functional efficiency of decomposing and purifying harmful gases such as formaldehyde and toluene in indoor air, and reaches and exceeds the national JC/T1074-2008 "Purification Performance of Indoor Air Purifying Functional Materials" standard , will not cause secondary pollution, and will release negative oxygen ions, and the dosage is small, easy to construct, smooth and delicate surface, high hardness, still bright as porcelain after washing, moisture-proof, mildew-proof, and low cost.

Although the present invention has been described in detail with general descriptions and specific embodiments above, it is obvious to those skilled in the art that some modifications or improvements can be made on the basis of the present invention. Therefore, the modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the protection scope of the present invention.

Claims (7)

1. The composite photocatalytic material of porous silicon dioxide and titanium dioxide is characterized in that its preparation method comprises the following steps: adding urea to the solution containing Ti ⁴⁺ , heating the urea solution to hydrolyze to generate NH ⁴⁺ and OH ^- , and then the solution The ^OH- in the reaction is combined with Ti ⁴⁺ to form TiO(OH) ₂ crystals, and the porous silica is used as a carrier to coat the TiO(OH) ₂ precipitated in the reaction on the surface of the porous silica, which is filtered, washed and dried , Calcined, TiO ₂ obtained by decomposing TiO(OH) ₂ is more firmly combined on the surface of porous silica, and then mixed with negative ion powder to disperse, that is. 2. The composite photocatalytic material according to claim 1, characterized in that, the raw material of the porous silica is from one or more of diatomite, zeolite powder, and synthetic silica. 3. composite photocatalytic material according to claim 1 and 2, is characterized in that, described anion powder is tourmaline powder. 4. The application of the composite photocatalytic material described in any one of claims 1-3 in coating preparation. 5. A coating with antibacterial and air-purifying functions, characterized in that the weight percentage of each component is:

6. coating according to claim 5 is characterized in that, the raw material of described organic polymer comes from dispersible latex powder and/or polyvinyl alcohol powder. 7. The coating according to claim 5 or 6, wherein the calcium carbonate is 250-800 mesh, the ash calcium powder is 400-800 mesh, and the talcum powder is 300-2500 mesh.