Dexdextrin modified interior wall coating and preparation method thereof

Abstract

The invention relates to a dextrin modified interior wall coating and a preparation method thereof. The invention provides a dextrin modified interior wall coating. The dextrin modified interior wall coating is prepared from the following components in parts by weight: 35 to 36 parts of water, 0.2 to 0.3 part of a de-foaming agent, 1.2 to 1.4 parts of a coalescing agent, 0.5 to 0.6 part of a thickening agent, 30 to 32 parts of filler and 20 to 25 parts of bio-based emulsion. The dextrin modified interior wall coating provided by the invention has good stability, can be stored for a long time, and has mildew-proof and degerming effects.

Description

Technical Field

[0001] The invention belongs to the field of coatings, and in particular relates to a dextrin-modified interior wall coating and a preparation method thereof. Background Art

[0002] Dextrin is a common polysaccharide food raw material. It is a low-conversion product between starch and starch sugar. In addition, it is also a water-soluble polymer compound that can significantly reduce the surface tension of the liquid and maintain the original rheological properties of the liquid, thereby improving the stability of the liquid. Therefore, it is widely used in food, medicine, and materials fields.

[0003] Interior wall paint is a type of paint used for indoor wall decoration and protection. They can not only beautify the indoor environment, but also protect the wall from moisture, stains and other damage. With the development of science and technology and the improvement of living standards, more and more indoor scenes need to apply paint to achieve the characteristics of pursuing beauty, heat preservation and moisture insulation. With the development of architectural design concepts, interior wall paint also pays more attention to environmental protection and intelligence. Through the application of smart coatings and nanotechnology, interior wall paint will have functions such as self-cleaning, smart color change and energy storage to meet the needs of future smart homes and sustainable buildings.

[0004] With the development of the construction industry, people's requirements for living environment are also increasing. In life scenarios, middle-aged and elderly users and people with special immune deficiencies need a special sterile living environment. It is particularly necessary to develop an interior wall paint with good stability, long-term preservation and mildew and sterilization effects. Summary of the invention

[0005] The present invention aims to overcome the above-mentioned defects in the prior art and provides a dextrin-modified interior wall paint and a preparation method thereof. The interior wall paint provided by the present invention has good stability and can be preserved for a long time and has anti-mildew and antibacterial effects.

[0006] The present invention provides the following technical solutions to solve the above-mentioned technical problems.

[0007] The present invention provides a dextrin-modified interior wall paint, which comprises, by weight, 32-38 parts of water, 0.1-0.3 parts of a defoamer, 1.0-1.5 parts of a film-forming aid, 0.5-0.6 parts of a thickener, 30-32 parts of a filler and 20-25 parts of a bio-based emulsion, wherein the bio-based emulsion is prepared by the following steps:

[0008] (1) mixing component A with a solvent (e.g., water) to obtain a modified dextrin emulsion, wherein component A comprises a base (e.g., sodium bicarbonate), dextrin, epichlorohydrin, and an emulsifier (e.g., dodecylphenol polyether and / or sodium dodecyl diphenyl oxide disulfonate);

[0009] (2) mixing component B with a solvent (e.g., water) to obtain an ethylenic monomer emulsion; wherein component B comprises an emulsifier (e.g., dodecylphenol polyether and / or sodium dodecyl diphenyl oxide disulfonate), methacrylamide, butyl acrylate, styrene, and methacrylic acid;

[0010] (3) mixing the vinyl monomer emulsion, the modified dextrin emulsion and an initiator (such as ammonium persulfate) to perform an emulsion polymerization reaction;

[0011] (4) After the emulsion polymerization reaction is completed, 2-amino-2-methyl-1-propanol is added to adjust the pH range of the reaction system to between 4 and 5, and then tert-butyl hydroperoxide and FF-6M are added; and then 2-amino-2-methyl-1-propanol is added to adjust the pH range to between 5.5 and 6.5 to obtain the bio-based emulsion.

[0012] In the present invention, in step (3), the step of emulsion polymerization reaction is preferably as follows: under the condition of an initiator (such as ammonium persulfate), 1 / 2 part of the olefinic monomer emulsion is dropwise added to the modified dextrin emulsion for emulsion polymerization reaction, and then the remaining 1 / 2 part of the olefinic monomer emulsion is fully mixed with vinyltrimethoxysilane and then dropwise added to the modified dextrin emulsion for emulsion polymerization reaction.

[0013] In the present invention, the component A further comprises 2,3-epoxypropyltrimethylammonium chloride.

[0014] In the present invention, in component A, the mass ratio of dextrin to 2,3-epoxypropyltrimethylammonium chloride is 25:3.

[0015] In the present invention, the defoamer is a conventional polyether defoamer in the art, such as BYK-012.

[0016] In the present invention, the thickener is a conventional alkali swelling thickener in the art, such as TT615.

[0017] In the present invention, the film-forming aid is a conventional film-forming aid in the art, such as YT-12.

[0018] In the present invention, the filler is a mixture of titanium dioxide, kaolin and talcum powder in a mass ratio of 3:20:20.

[0019] In the present invention, the dextrin-modified interior wall paint may further contain a mildew preventer, such as a benzisothiazoline compound, preferably 1,2-benzisothiazolin-3-one.

[0020] In the present invention, the dextrin-modified interior wall paint contains 0.2-0.4 parts of mildew inhibitor.

[0021] The invention provides a method for preparing interior wall paint, which is the same as the method for preparing the dextrin-modified interior wall paint.

[0022] The invention also provides the use of the dextrin-modified interior wall paint as a paint.

[0023] The present invention also provides a bio-based emulsion, wherein the bio-based emulsion is as defined above.

[0024] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0025] The reagents and raw materials used in the present invention are commercially available.

[0026] The positive improvement effect of the present invention is that the dextrin-modified interior wall paint provided by the present invention has good stability and can be preserved for a long time and has mildew-proof and sterilization effects. DETAILED DESCRIPTION

[0027] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0028] Example 1

[0029] Step 1: Preparation of bio-based emulsion:

[0030] The bio-based latex formula is shown in Table 1.

[0031] Table 1

[0032]

[0033]

[0034] Step 1.1: Preparation of modified dextrin emulsion

[0035] Refer to the materials and dosages in Table 1: add deionized water to a 500ml three-necked bottle, add dextrin under stirring, and keep warm at 80°C for 30 minutes. Then add aqueous solutions of sodium bicarbonate, epichlorohydrin, sodium dodecyl diphenyl ether disulfonate and dodecylphenol polyether in sequence, and keep warm at 80°C for 1 hour; thus, a modified dextrin emulsion is obtained.

[0036] Step 1.2: Emulsion polymerization of vinyl monomers

[0037] Referring to the materials and amounts in Table 1: water, sodium dodecyl diphenyl ether disulfonate, dodecylphenol polyether, and methacrylamide were added to a 500 ml three-necked bottle, and the mixture was stirred for 10 min. Then, butyl acrylate, styrene, and methacrylic acid were added, and the mixture was rapidly stirred for 20 min to obtain an emulsion of olefin monomers.

[0038] Then the above-mentioned ethylenic monomer emulsion is divided into two equal parts, wherein: one part is not added with vinyltrimethoxysilane; and the other part is added with vinyltrimethoxysilane to obtain an ethylenic monomer emulsion containing vinyltrimethoxysilane.

[0039] The alkenyl monomer emulsion not containing vinyltrimethoxysilane is added dropwise to the modified dextrin emulsion (the addition is completed in 2 hours), wherein, after 0.5 hours of the addition of the alkenyl monomer emulsion not containing vinyltrimethoxysilane, the ammonium persulfate solution is simultaneously started to be added dropwise (the dropping speed is 2.5 ml / h, and the addition is completed in 4 hours); then the alkenyl monomer emulsion containing vinyltrimethoxysilane is added dropwise to the reaction solution, and the addition is completed in 2 hours; after the addition is completed, stirring is continued at 80°C for 1 hour to allow the alkenyl monomer to fully undergo emulsion polymerization.

[0040] Step 1.3: Removal of residual vinyl monomers from the emulsion

[0041] Refer to the materials and dosages in Table 1: The above reaction system was cooled to 55°C, 2-amino-2-methyl-1-propanol (AMP-95) was added to adjust the pH range to between 4 and 5, and then tert-butyl hydroperoxide and FF-6M were dissolved in water, added dropwise simultaneously, and added for 1 hour, and then kept warm for 0.5 hours to fully remove the residual olefin monomer. Then the reaction system was cooled to below 40°C, 2-amino-2-methyl-1-propanol (AMP-95) was added to further adjust the pH to about 6 to obtain the bio-based emulsion.

[0042] Step 2: Preparation of dextrin-modified interior wall coating

[0043] In parts by weight: 35 parts of water, 0.2 parts of polyether defoamer BYK-012, 1.3 parts of film-forming aid YT-12 and 0.5 parts of thickener TT615 are mixed, 30 parts of filler are added and ground until the slurry fineness is less than 50 μm, and then 22 parts of the above-mentioned bio-based emulsion and 0.3 parts of mildewproofing agent 1,2-benzisothiazolin-3-one are added to obtain the dextrin-modified interior wall coating, wherein the filler is titanium dioxide, kaolin and talc mixed in a mass ratio of 3:20:20 to obtain the dextrin-modified interior wall coating.

[0044] Example 2

[0045] Except for step 1.1 of Example 1, refer to the preparation method of Example 1. Specifically, the operation of step 1.1 of Example 2 is as follows:

[0046] Refer to the materials and amounts in Table 1: Add deionized water to a 500 ml three-necked bottle, add dextrin and 2,3-epoxypropyltrimethylammonium chloride (3 g) while stirring, and keep warm at 80°C for 30 min.

[0047] Then, sodium bicarbonate, epichlorohydrin, sodium dodecyl diphenyl ether disulfonate and aqueous solution of dodecylphenol polyether were added in sequence, kept warm at 80°C for 1 hour, and then ammonium persulfate solution was added dropwise (at a rate of 100 ml / h). After the addition was completed, the reaction was continued for 10 minutes; thereby, a modified dextrin emulsion was obtained.

[0048] Example 3

[0049] Except for step 2 of Example 2, the preparation method of Example 2 is referred to. Specifically, in step 2 of Example 3, no mildew inhibitor is added.

[0050] Example 4

[0051] Except for step 1.2 of Example 1, refer to the preparation method of Example 1. Specifically, the operation of step 1.2 of Example 4 is as follows:

[0052] Refer to the materials and amounts in Table 1: add water, sodium dodecyl diphenyl ether disulfonate, dodecylphenol polyether, and methacrylamide to a 500 ml three-necked bottle, stir and mix for 10 minutes, then add butyl acrylate, styrene, methacrylic acid and vinyl trimethoxysilane, and stir rapidly for 20 minutes to obtain an emulsion of olefin monomers.

[0053] Then, the olefin monomer emulsion was added dropwise to the modified dextrin emulsion, wherein, after 0.5 h of dropping, the ammonium persulfate solution was simultaneously added dropwise; after the dropping was completed, stirring was continued at 80° C. for 1 h to allow the olefin monomer to fully undergo emulsion polymerization.

[0054] Comparative Example 1

[0055] Except for step 1.1 of Example 1, the preparation method of Example 1 is referred to. Specifically, Comparative Example 1 does not include step 1.1.

[0056] Comparative Example 2

[0057] Except for step 2 of Example 1, the preparation method of Example 1 is referred to. Specifically, in step 2 of Comparative Example 2, no mildew inhibitor is added.

[0058] Effect Example 1

[0059] Freeze-thaw stability: Freeze-thaw cycle: Referring to GB9268-2008, take the bio-based emulsion prepared in each example or comparative example and put it into a glass bottle, seal it, and place it at (-10±2)℃ for 18 hours, then place it at room temperature for 6 hours, and observe the state of the emulsion after sufficient stirring. If no coagulants appear, repeat the above freeze-thaw cycle until coagulants appear. The number of freeze-thaw cycles increases by 1 for each freeze-thaw cycle, and the results are expressed in numbers.

[0060] Calcium ion stability (calcium stability): Referring to GB / T20623-2006, add the bio-based emulsion prepared in each example or comparative example and a CaCl2 solution with a mass fraction of 1-3% in a beaker at a weight ratio of 5:1, stir well and place in a 50mL stoppered measuring cylinder, let it stand for 48 hours and observe whether there are stratification, precipitation, flocculation and other phenomena. If any, the result is failed.

[0061] The bio-based emulsions prepared in Examples 1-4 and Comparative Examples 1-2 were subjected to the above freeze-thaw stability and calcium ion stability tests. The test results are shown in Table 2.

[0062] Table 2

[0063]

[0064] According to Table 2, the difference between the bio-based emulsions of Comparative Example 1 and Example 1 is that the bio-based emulsion of Comparative Example 1 does not contain the modified dextrin component, but its freeze-thaw cycle number and calcium ion stability are far inferior to those of Example 1. It can be seen that the modified dextrin has a significant stabilizing effect on the bio-based emulsion.

[0065] In addition, according to Table 2, the difference between the bio-based emulsions of Example 1 and Example 4 is that the preparation methods during emulsion polymerization are different, however, the bio-based emulsion of Example 1 has better stability. It can be seen that the preparation method of the emulsion polymerization reaction has an important influence on the stability of the finally prepared bio-based emulsion.

[0066] Effect Test Example 2

[0067] Antibacterial performance test: Tested in accordance with GB / T21866-2008 standard requirements. The antibacterial rate is 90-100% represented by A, the antibacterial rate is 50-90% represented by B, and the antibacterial rate is 0-50% represented by C.

[0068] Anti-fungal performance test: Test strains: Aspergillus niger AS3.4463, Aspergillus terreus AS3.3935. Test method: Within 15 days, the mold was placed in a humidity of 90% RH and a temperature of 28°C. Evaluation criteria: Level 1: no growth, that is, no growth was observed under a microscope (magnification 50 times); Level 2: trace growth, that is, growth was visible to the naked eye, but the growth coverage area was less than 10%; Level 3: the growth coverage area was greater than 10%.

[0069] Test material preparation: The dextrin-modified interior wall coatings of Examples 1-4 and Comparative Examples 1-2 were respectively coated on a glass substrate and cured to form a coating film with a coating film thickness of 10-15 μm and a coating film area of ​​0.04 m 2 ; Prepare the corresponding test materials.

[0070] The dextrin-modified interior wall coatings prepared in Examples 1-4 and Comparative Examples 1-2 were subjected to the above-mentioned antibacterial performance test and antifungal performance test, respectively. The experimental results are shown in Table 3.

[0071] Table 3

[0072]

[0073] As shown in Table 3 above, the dextrin-modified interior wall coating provided by the present invention has an excellent anti-mildew effect, especially in Example 3, which does not add a mildew inhibitor, but still has an excellent anti-mildew effect. This may be due to the reaction of 2,3-epoxypropyltrimethylammonium chloride with dextrin to form a dextrin quaternary ammonium salt, which itself has excellent anti-mildew and antibacterial properties. Moreover, the dextrin-modified interior wall coating provided by the present invention also has an excellent antibacterial effect.

Claims

1. A dextrin-modified interior wall paint, characterized in that: The method comprises, by weight, 32-38 parts of water, 0.1-0.3 parts of defoaming agent, 1.0-1.5 parts of film-forming aid, 0.5-0.6 parts of thickener, 30-32 parts of filler and 20-25 parts of bio-based emulsion, wherein the bio-based emulsion is prepared by the following steps: (1) mixing component A with water to obtain a modified dextrin emulsion, wherein the component A comprises sodium bicarbonate, dextrin, epichlorohydrin, dodecylphenol polyether and sodium dodecyl diphenyl oxide disulfonate; (2) mixing component B with water to obtain an ethylenic monomer emulsion, wherein component B comprises dodecylphenol polyether, sodium dodecyl diphenyl oxide disulfonate, methacrylamide, butyl acrylate, styrene and methacrylic acid; (3) mixing the vinyl monomer emulsion, the modified dextrin emulsion and ammonium persulfate to perform an emulsion polymerization reaction; (4) After the emulsion polymerization reaction is completed, 2-amino-2-methyl-1-propanol is added to adjust the pH range of the reaction system to between 4 and 5, and then tert-butyl hydroperoxide and FF-6M are added; and then 2-amino-2-methyl-1-propanol is added to adjust the pH range to between 5.5 and 6.5 to obtain the bio-based emulsion.

2. The dextrin-modified interior wall paint according to claim 1, characterized in that: In step (3), the emulsion polymerization reaction is carried out as follows: under the catalysis of ammonium persulfate, 1 / 2 part of the olefinic monomer emulsion obtained in step (2) is dropwise added to the modified dextrin emulsion for emulsion polymerization reaction, and then the remaining 1 / 2 part of the olefinic monomer emulsion is fully mixed with vinyltrimethoxysilane and then dropwise added to the reaction system for emulsion polymerization reaction.

3. The dextrin-modified interior wall paint according to claim 1, characterized in that: The component A further comprises 2,3-epoxypropyltrimethylammonium chloride.

4. The dextrin-modified interior wall paint according to claim 3, characterized in that: In component A, the mass ratio of dextrin to 2,3-epoxypropyltrimethylammonium chloride is 25:

3.

5. The dextrin-modified interior wall paint according to claim 1, characterized in that: The defoamer is BYK-012.

6. The dextrin-modified interior wall paint according to claim 1, characterized in that: The thickener is TT-615.

7. The dextrin-modified interior wall paint according to claim 1, characterized in that: The film-forming aid is YT-12.

8. The dextrin-modified interior wall paint according to claim 1, characterized in that: The filler is a mixture of titanium dioxide, kaolin and talcum powder in a mass ratio of 3:20:

20.

9. The dextrin-modified interior wall paint according to claim 1, characterized in that: The dextrin-modified interior wall paint may further contain a mildew preventer, and the mildew preventer is 1,2-benzisothiazolin-3-one.

10. A method for preparing interior wall paint, characterized in that: The method comprises the following steps: mixing 35-36 parts of water, 0.2-0.3 parts of defoaming agent, 1.2-1.4 parts of film-forming aid, 0.5-0.6 parts of thickener, 30-32 parts of filler and 20-25 parts of bio-based emulsion by weight, wherein the bio-based emulsion is prepared by the following steps: (1) mixing component A with water to obtain a modified dextrin emulsion, wherein the component A comprises sodium bicarbonate, dextrin, epichlorohydrin, dodecylphenol polyether and sodium dodecyl diphenyl oxide disulfonate; (2) mixing component B with water to obtain an ethylenic monomer emulsion, wherein component B comprises dodecylphenol polyether, sodium dodecyl diphenyl oxide disulfonate, methacrylamide, butyl acrylate, styrene and methacrylic acid; (3) mixing the vinyl monomer emulsion, the modified dextrin emulsion and ammonium persulfate to perform an emulsion polymerization reaction; (4) After the emulsion polymerization reaction is completed, 2-amino-2-methyl-1-propanol is added to adjust the pH range of the reaction system to between 4 and 5, and then tert-butyl hydroperoxide and FF-6M are added; and then 2-amino-2-methyl-1-propanol is added to adjust the pH range to between 5.5 and 6.5 to obtain the bio-based emulsion.

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