Molecular sieve modification method and latex paint

Abstract

The invention provides a molecular sieve modification method and latex paint, and relates to the technical field of paint. The molecular sieve modification method comprises the following steps: mixing a molecular sieve and a carbon nanotube, carrying out primary ball milling, taking out, heating and activating to obtain a premix; and mixing the premix with acrylate rubber powder, and carrying out secondary ball milling to obtain the modified molecular sieve. When the modified molecular sieve obtained by the invention is added into the latex paint, the sound absorption, noise reduction and formaldehyde adsorption performance of the latex paint can be obviously improved, and the dispersion stability is good.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings and relates to a molecular sieve modification method and latex paint. Background Art

[0002] Interior wall latex paint is one of the main decorative materials for indoor walls and ceilings, and is characterized by good decorative effect, convenient construction, low environmental pollution, low cost and extremely wide application. As people's requirements for quality of life and living environment become higher and higher, more requirements are put forward for the functions of interior wall latex paint. Noise pollution and formaldehyde pollution have adverse effects on people's physical and mental health, especially when they occur indoors. In order to improve the above problems, the prior art CN113736321A discloses a method of adding mineral fiber to the emulsion to improve the sound absorption effect. The prior art CN114806246A discloses a method of adding active silicon loaded with Na and Pt to the latex paint to improve the degradation performance of formaldehyde. There is also a prior art that adds a large amount of diatomaceous earth to the interior wall paint to achieve formaldehyde adsorption and sound absorption and denoising, but the sound absorption and denoising performance of this interior wall paint is relatively poor, and it is easy to get damp in a humid environment, causing the latex paint to have problems such as bubbling and getting hands dirty, and it is not suitable for washing with water.

[0003] Therefore, it is necessary to further improve the existing latex paint to enhance the ability to solve noise pollution and formaldehyde pollution. Summary of the invention

[0004] After extensive research, testing and analysis, the inventors found that the properties of carbon nanotubes and molecular sieves can be used to modify and add them to latex paint to significantly improve the sound absorption and formaldehyde adsorption functions of latex paint. In view of this, the present invention proposes a molecular sieve modification method and latex paint.

[0005] The technical solution of the present invention is as follows:

[0006] A molecular sieve modification method comprises the following steps:

[0007] The molecular sieve and the carbon nanotubes are mixed and ball-milled for the first time, taken out, and heated and activated to obtain a premix;

[0008] The premix and acrylic rubber powder are mixed and ball-milled for a second time to obtain a modified molecular sieve.

[0009] Preferably, the weight ratio of the molecular sieve to the carbon nanotubes is 10:1-1:1.

[0010] Preferably, the carbon nanotubes are selected from at least one of single-walled carbon nanotubes and multi-walled carbon nanotubes.

[0011] Preferably, the conditions for the first ball milling are: adding 30-55% volume of steel grinding balls into the ball milling jar, and ball milling at a rotation speed of 80-150 rpm / min for 10-60 min.

[0012] Preferably, the heating activation condition is heating at 100-150° C. for 12-48 hours.

[0013] Preferably, the weight ratio of the premix to the acrylic rubber powder is 1:2-3:1.

[0014] Preferably, the conditions for the second ball milling are: adding 25-45% volume of steel grinding balls into the ball milling jar, and ball milling at a speed of 250-400 rpm / min for 3-12 hours.

[0015] A latex paint, the raw material components of which include emulsion, modified molecular sieve obtained by the molecular sieve modification method described in any one of the technical solutions above, pigments, fillers and additives.

[0016] Preferably, the weight proportion of the emulsion in the latex paint is 15-30%.

[0017] Preferably, the weight proportion of the modified molecular sieve in the latex paint is 5-25%.

[0018] The beneficial effects of the present invention are:

[0019] (1) The present invention utilizes the characteristics of molecular sieves and carbon nanotubes, and performs modified combination, and adding them into latex paint can significantly improve the sound absorption and formaldehyde adsorption performance of the latex paint.

[0020] (2) The modified molecular sieve of the present invention further introduces an acrylate structure, which improves the spatial distribution of the modified molecular sieve and its compatibility with latex paint, is beneficial to the dispersion of the modified molecular sieve in latex paint and maintains good dispersion and stability, thereby exerting good technical effects of sound absorption, denoising and formaldehyde adsorption. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further illustrated and described below through specific implementation methods.

[0022] In order to improve the sound absorption and formaldehyde adsorption effects of latex paint, on the one hand, the present invention provides a molecular sieve modification method, comprising the following steps:

[0023] The molecular sieve and the carbon nanotubes are mixed and ball-milled for the first time, taken out, and heated and activated to obtain a premix;

[0024] The premix and the acrylic rubber powder are mixed and ball-milled for the second time to obtain the modified molecular sieve.

[0025] In the present invention, the molecular sieve is modified by using carbon nanotubes, which has the following characteristics and effects: (1) The interior of the carbon nanotubes is a nanoscale hollow hole structure, and the molecular sieve structure is rich in nanoscale micropores. The carbon nanotube-modified molecular sieve connects the micropores on the molecular sieve through the hollow hole structure of the carbon nanotubes, forming a large number of relatively long nanoscale holes in different directions and distances. The sound is reflected countless times in these relatively long nanoscale holes. The energy of the sound waves is consumed and converted into heat energy in this process, forming a sound absorption and noise reduction effect. (2) Due to the presence of a large number of relatively long holes in different directions and distances, the carbon nanotube-modified molecular sieve also improves the adsorption capacity and ability of formaldehyde, and has good formaldehyde adsorption performance. (3) The modified molecular sieve is further modified by using acrylic ester powder, which improves the compatibility of the modified molecular sieve with polymers (such as latex paint), and the modified molecular sieve has better dispersibility in latex paint and can play a better role. (4) The modification of molecular sieve by carbon nanotubes expands the spatial three-dimensional structure of molecular sieve, which is beneficial to the dispersion uniformity and dispersion stability of modified molecular sieve in latex paint. (5) The modification is carried out by ball milling, which is suitable for industrial production.

[0026] In the present invention, the molecular sieve is not particularly limited, and can be A-type molecular sieve, T-type molecular sieve, ZSM series molecular sieve, X-type molecular sieve, Y-type molecular sieve, etc., such as 3A molecular sieve, 4A molecular sieve, 5A molecular sieve, 13X molecular sieve, etc.

[0027] In a preferred embodiment of the present invention, the weight ratio of the molecular sieve to the carbon nanotube is 10:1-1:1. For example, the weight ratio of the molecular sieve to the carbon nanotube can be any value or any value in between 10:1, 9.5:1, 9:1, 8.5:1, 8:1, 7.5:1, 7:1, 6.5:1, 6:1, 5.5:1, 5:1, 4.5:1, 4:1, 3.5:1, 3:1, 2.5:1, 2:1, 1.5:1, 1:1, etc., without special restrictions. Further preferably, the weight ratio of the molecular sieve to the carbon nanotube can be 8:1-1:1.

[0028] In a preferred embodiment of the present invention, the carbon nanotubes are selected from at least one of single-walled carbon nanotubes SWMT and multi-walled carbon nanotubes MWNT. SWMT is composed entirely of carbon atoms, and its geometric structure can be regarded as a single-layer graphene curled up, with an inner diameter generally of 0.6-2nm. MWMT is composed entirely of carbon atoms, and its geometric structure can be regarded as two or more layers of graphene curled up, with an inner diameter generally of 1-5nm. Therefore, the inner diameter of the carbon nanotube is relatively close to the pore size of the molecular sieve, and the carbon nanotube can form a large number of interconnected longer nanoscale holes with the molecular sieve, which has good sound absorption, denoising and formaldehyde adsorption effects. Moreover, the structure of the carbon nanotube-modified molecular sieve can have a higher volume share when added to oily or water-based paints due to the higher aspect ratio of the carbon nanotubes, and can be better dispersed and has better dispersion uniformity and dispersion stability.

[0029] In a preferred embodiment of the present invention, the conditions for the first ball milling are: adding 30-55% volume of steel grinding balls to the ball milling jar, and ball milling at a speed of 80-150rpm / min for 10-60min. The conditions for the second ball milling are: adding 25-45% volume of steel grinding balls to the ball milling jar, and ball milling at a speed of 250-400rpm / min for 3-12h. The above-mentioned ball milling method is suitable for industrial production, and the modification is relatively simple, without the need to add other modifiers. Generally, under the appropriate steel grinding ball filling rate, the higher the ball milling speed, the shorter the ball milling time, for example, the first ball milling can be 100rpm×30min, 120rpm×20min, 140rpm×15min, etc., without special restrictions; the second ball milling can be 350rpm×6h, 400rpm×3h, 300rpm×9h, etc., without special restrictions.

[0030] In a preferred embodiment of the present invention, the heating activation condition is heating at 100-150°C for 12-48h. Under the above activation conditions, the carbon nanotube-modified molecular sieve can have a higher reactivity, which is beneficial to the next step of reaction with acrylate rubber powder, and the carbon nanotube-modified molecular sieve is further modified to graft acrylate groups and / or acrylate polymer structures on the surface. For example, the heating activation conditions can be 120°C×24h, 130°C×16h, 150°C×12h, 100°C×48h, etc., without special restrictions.

[0031] In a preferred embodiment of the present invention, the weight ratio of the premix to the acrylic rubber powder is 1:2-3:1. For example, the weight ratio of the premix to the acrylic rubber powder can be any value of 1:2, 1:1.5, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, etc. or any value in between, without particular limitation.

[0032] On the other hand, the present invention provides a latex paint, the raw material components of which include an emulsion, a modified molecular sieve obtained by the molecular sieve modification method described in any of the above technical solutions, a pigment, a filler and an auxiliary agent. The surface of the modified molecular sieve of the present invention is grafted with an acrylate structure, so it has good compatibility with the emulsion, can form good dispersibility in the emulsion and play a good role in sound absorption, noise reduction and formaldehyde adsorption. In the present invention, there is no special restriction on the pigment, the filler (based on the weight of the emulsion, the amount can be 10-40%) can be an organic filler or an inorganic filler, the organic filler can be polyethylene powder, polytetrafluoroethylene powder, etc., the inorganic filler can be kaolin, silica powder, talc, heavy calcium carbonate, light calcium carbonate, aluminum oxide, magnesium oxide, zinc oxide, silicon dioxide, diatomaceous earth, etc., the pigment (based on the weight of the emulsion, the amount can be 0.5-40%) can be titanium dioxide, phthalocyanine blue, phthalocyanine green, etc., can be directly purchased from the market. The additives may be dispersants (based on the weight of the emulsion, the amount may be 0.5-1.5%), leveling agents (based on the weight of the emulsion, the amount may be 0.4-1%), defoamers (based on the weight of the emulsion, the amount may be 0.6-1.5%), anti-settling agents (based on the weight of the emulsion, the amount may be 0.2-0.6%), anti-ultraviolet agents (based on the weight of the emulsion, the amount may be 0.1-0.6%), anti-yellowing agents (based on the weight of the emulsion, the amount may be 0.1-0.6%), wetting agents (based on the weight of the emulsion, the amount may be 0.1-0.6%). The amount of the emulsion can be 0.4-1%, thickener (based on the weight of the emulsion, the amount can be 0.5-1.5%), thixotropic agent (based on the weight of the emulsion, the amount can be 0.5-2%), preservative (based on the weight of the emulsion, the amount can be 0.1-0.6%), bactericide (based on the weight of the emulsion, the amount can be 0.2-0.5%), film-forming aid (based on the weight of the emulsion, the amount can be 1-2%), pH regulator (appropriate amount), etc., can be directly purchased from the market. Appropriate water can also be added to adjust the viscosity or solid content, etc.

[0033] In a preferred embodiment of the present invention, the weight proportion of the emulsion in the latex paint is 15-30%. In the present invention, the emulsion can be an acrylic resin emulsion or a modified acrylic resin emulsion, such as an epoxy-modified acrylic resin emulsion, a polyurethane-modified acrylic resin emulsion, a silicone-modified acrylic resin emulsion, etc., and the solid content of the emulsion can be 30-60wt%. For example, the weight proportion of the emulsion in the latex paint can be any value or any value between 15%, 18%, 20%, 22%, 23%, 25%, 27%, 28%, 30%, etc., without special restrictions.

[0034] In a preferred embodiment of the present invention, the weight proportion of the modified molecular sieve in the latex paint is 5-25%, which can achieve a good effect of sound absorption and formaldehyde adsorption. For example, the weight proportion of the modified molecular sieve in the latex paint can be 5%, 8%, 10%, 12%, 13%, 15%, 17%, 18%, 20%, 22%, 25%, etc., or any value in between, without special restrictions.

[0035] In the present invention, the preparation method of latex paint is not particularly limited and can be carried out according to conventional methods, such as adding each raw material component in sequence and then stirring and dispersing, or adding each raw material component in batches and then stirring and dispersing.

[0036] The present invention also found that the dispersant disperses the pigment and filler particles of different sizes into stable microparticles and then evenly distributes them around the modified molecular sieve, further improving the dispersion stability of the modified molecular sieve in the latex paint, and the interaction between the modified molecular sieve and the pigment and filler particles is strong, which helps to stabilize the pigment and filler particles, avoid the appearance of roughening of the latex paint, improve the ability of the dry film to resist blooming, and reduce the risk of roughening of the wet film of the latex paint and floating color and blooming of the dry film. However, if the content of the modified molecular sieve in the latex paint is too high, the dispersion stability will deteriorate, resulting in precipitation after being placed for a period of time.

[0037] The technical solution of the present invention is further described and illustrated according to various embodiments below. Unless otherwise specified, the parts described in the following embodiments are parts by weight.

[0038] Example 1-5 Preparation of modified molecular sieve

[0039] Example 1

[0040] 75 g of 13X molecular sieve and 25 g of single-walled carbon nanotubes were placed in a ball mill respectively, 40% volume of steel grinding balls were added to the ball mill, and the mixture was ball milled at a speed of 100 r / min for 30 min to obtain a premix;

[0041] The premix was placed in a tubular furnace and kept at 120°C for 24 h for activation;

[0042] 50 g of activated premix and 50 g of acrylic rubber powder (LDM7000P from Japan Synthetic Chemical) were placed in a ball mill, 35% volume of steel grinding balls were added to the ball mill, and the mixture was ball milled at a speed of 350 r / min for 6 h to obtain a modified molecular sieve.

[0043] Example 2

[0044] The difference between this embodiment and embodiment 1 is that in embodiment 1, 75 g of 13X molecular sieve is adjusted to 88 g, and 25 g of single-walled carbon nanotube is adjusted to 12 g. The other steps remain unchanged.

[0045] Example 3

[0046] The difference between this embodiment and embodiment 1 is that in embodiment 1, 75g of 13X molecular sieve is adjusted to 50g, and 25g of single-walled carbon nanotube is adjusted to 50g. The other steps remain unchanged.

[0047] Example 4

[0048] The difference between this embodiment and embodiment 1 is that in embodiment 1, 50g of activated premix is ​​adjusted to 75g, and 50g of acrylate rubber powder is adjusted to 25g. The other steps remain unchanged.

[0049] Example 5

[0050] The difference between this embodiment and embodiment 1 is that in embodiment 1, 50g of activated premix is ​​adjusted to 34g, and 50g of acrylate rubber powder is adjusted to 66g. The other steps remain unchanged.

[0051] Example 6-14 Preparation of latex paint

[0052] The raw materials of the latex paint of the following embodiments and comparative examples are as follows:

[0053] Lotion: BLJ-818Z.

[0054] Dispersant: SN5040 dispersant.

[0055] Defoamer: FoamStar ST 2410 defoamer.

[0056] Wetting agent: SN-WET 996.

[0057] Thickener: Hydroxyethylcellulose 250HBR.

[0058] Preservative:Defros CP11.

[0059] Titanium dioxide: R-996 rutile titanium dioxide.

[0060] Heavy calcium carbonate: Liangde nano powder D-3000.

[0061] Diatomaceous earth: CELATOM MW25.

[0062] Kaolin: DG80.

[0063] pH adjuster: AMP-95.

[0064] Fungicide: Hebei Hofman Defros CP11EX.

[0065] Coal-forming aid: Eastman dodecyl alcohol.

[0066] Example 6

[0067] The latex paint is composed of 20% emulsion, 5% modified molecular sieve of Example 1, 0.8% dispersant, 0.6% wetting agent, 0.7% defoamer, 0.9% thickener, 0.5% preservative, 10% titanium dioxide, 17% heavy calcium carbonate, 10% diatomaceous earth, 5% kaolin, 0.2% pH regulator, 0.4% bactericide, 1.5% film-forming aid and the balance water, and is prepared into 10 kg of latex paint.

[0068] Add the formulated amount of water to a suitable container and start stirring. While stirring at 350 rpm, slowly add dispersant, wetting agent, and modified molecular sieve in turn, and stir for 3 minutes; while stirring at 800 rpm, slowly add diatomaceous earth, titanium dioxide, kaolin, and heavy calcium carbonate in turn, and stir for 5 minutes; while stirring at 900 rpm, slowly add hydroxyethyl cellulose and pH adjuster in turn, increase the speed to 1200 rpm, and stir for 30 minutes; while stirring at 800 rpm, slowly add preservative, emulsion, bactericide, film-forming aid, and defoaming agent in turn, and stir for 10 minutes to obtain latex paint.

[0069] Example 7

[0070] The difference between this embodiment and embodiment 6 is that in embodiment 6, the modified molecular sieve is adjusted from 5% to 16%, and the weight content of water is reduced accordingly. The other steps remain unchanged.

[0071] Example 8

[0072] The difference between this embodiment and embodiment 6 is that in embodiment 6, the modified molecular sieve is adjusted from 5% to 25%, and the weight content of water is reduced accordingly. The remaining steps remain unchanged.

[0073] Comparative Example 1

[0074] The difference between this comparative example and Example 6 is that in Example 6, the modified molecular sieve is adjusted from 5% to 0, and the weight content of water is increased accordingly. The other steps remain unchanged.

[0075] Comparative Example 2

[0076] The difference between this comparative example and Example 6 is that in Example 6, the modified molecular sieve is adjusted from 5% to 28%, and the weight content of water is reduced accordingly. The other steps remain unchanged.

[0077] Comparative Example 3

[0078] The latex paint is composed of 20% emulsion, 12% 13X molecular sieve, 4% single-walled carbon nanotube, 0.8% dispersant, 0.6% wetting agent, 0.7% defoamer, 0.9% thickener, 0.5% preservative, 10% titanium dioxide, 17% heavy calcium carbonate, 10% diatomaceous earth, 5% kaolin, 0.2% pH regulator, 0.4% bactericide, 1.5% film-forming aid and the balance water, based on 100% by weight.

[0079] Comparative Example 4

[0080] The latex paint is composed of 20% emulsion, 16% modified molecular sieve, 0.8% dispersant, 0.6% wetting agent, 0.7% defoamer, 0.9% thickener, 0.5% preservative, 10% titanium dioxide, 17% heavy calcium carbonate, 10% diatomaceous earth, 5% kaolin, 0.2% pH regulator, 0.4% bactericide, 1.5% film-forming aid and the balance water, based on 100% by weight.

[0081] The modified molecular sieve was prepared as follows: 75 g of 13X molecular sieve, 25 g of single-walled carbon nanotubes and 100 g of acrylic rubber powder were respectively placed in a ball mill, 35% volume of steel grinding balls were added to the ball mill, and the ball mill was performed at a speed of 350 r / min for 6 hours to obtain the modified molecular sieve.

[0082] Comparative Example 5

[0083] The latex paint is composed of 20% emulsion, 16% 13X molecular sieve, 0.8% dispersant, 0.6% wetting agent, 0.7% defoamer, 0.9% thickener, 0.5% preservative, 10% titanium dioxide, 17% heavy calcium carbonate, 10% diatomaceous earth, 5% kaolin, 0.2% pH regulator, 0.4% bactericide, 1.5% film-forming aid and the balance water, based on 100% by weight.

[0084] Comparative Example 6

[0085] The latex paint is composed of 20% emulsion, 16% single-walled carbon nanotubes, 0.8% dispersant, 0.6% wetting agent, 0.7% defoamer, 0.9% thickener, 0.5% preservative, 10% titanium dioxide, 17% heavy calcium carbonate, 10% diatomaceous earth, 5% kaolin, 0.2% pH regulator, 0.4% bactericide, 1.5% film-forming aid and the balance water in an amount of 100% by weight.

[0086] Example 9

[0087] The difference between this embodiment and embodiment 6 is that in embodiment 6, the emulsion is adjusted from 20% to 25%, the modified molecular sieve is adjusted from 5% to 18%, and the weight content of water is reduced accordingly. The other steps remain unchanged.

[0088] Example 10

[0089] The difference between this embodiment and embodiment 9 is that in embodiment 9, the modified molecular sieve of embodiment 1 is adjusted to the modified molecular sieve of embodiment 2 with the same weight content. The other steps remain unchanged.

[0090] Embodiment 11

[0091] The difference between this embodiment and embodiment 9 is that in embodiment 9, the modified molecular sieve of embodiment 1 is adjusted to the modified molecular sieve of embodiment 3 with the same weight content. The other steps remain unchanged.

[0092] Example 12

[0093] The difference between this embodiment and embodiment 9 is that in embodiment 9, the modified molecular sieve of embodiment 1 is adjusted to the modified molecular sieve of embodiment 4 with the same weight content. The other steps remain unchanged.

[0094] Embodiment 13

[0095] The difference between this embodiment and embodiment 9 is that in embodiment 9, the modified molecular sieve of embodiment 1 is adjusted to the modified molecular sieve of embodiment 5 with the same weight content. The other steps remain unchanged.

[0096] Performance Testing

[0097] Average formaldehyde content in one hour: 25cm×25cm×2cm artificial boards coated with three layers of latex paint to be tested were dried at room temperature for 24 hours and placed in a 20L sealed container. After one hour, the formaldehyde content in the container was tested. Tested according to the method of GB / T18883-2022, the requirement is ≤0.03mg / m 3 .

[0098] Formaldehyde removal rate: 20cm×20cm×1mm clean tinplate coated with three layers of latex paint to be tested was dried at room temperature for 24 hours and then placed in a 20L sealed container. The initial formaldehyde content in the container was 1mg / m 3 . Test the formaldehyde content in the container after 1 hour of placement and calculate the formaldehyde removal rate.

[0099] Noise Reduction Coefficient: Tested in accordance with ISO 10534-2:2001.

[0100] Dispersion stability: Take 150g of the latex paint to be tested and place it in a 200mol transparent plastic bottle, seal it, and bake it in a 50℃ oven for 40h to observe whether there are abnormal conditions such as precipitation and stratification.

[0101] State in container: Tested according to the method of GB / T9756-2001.

[0102] Washability: Tested according to the method of GB / T9756-2001, the requirement is not less than 6000 times.

[0103] The results are shown in Table 1 below.

[0104] Table 1

[0105]

[0106]

[0107]

[0108] It can be seen from the data in Table 1 that the modified molecular sieve of the present invention can be added to latex paint to significantly improve the sound absorption and denoising and formaldehyde adsorption performance of the latex paint, and has good dispersion stability, is not prone to problems such as particle aggregation and coarsening, and the latex paint can also meet the requirements of washing.

[0109] As described above, the basic principles, main features and advantages of the present invention are shown and described. Those skilled in the art should understand that the present invention is not limited by the above embodiments, which are only preferred embodiments of the present invention and cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the scope of the present invention and the content of the specification should still be within the scope of the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents.

Claims

1. A molecular sieve modification method, characterized in that: The following steps are involved: The molecular sieve and the carbon nanotubes are mixed and ball-milled for the first time, taken out, and heated and activated to obtain a premix; The premix and acrylic rubber powder are mixed and ball-milled for a second time to obtain a modified molecular sieve.

2. The molecular sieve modification method according to claim 1, characterized in that: The weight ratio of the molecular sieve to the carbon nanotube is 10:1-1:

1.

3. The molecular sieve modification method according to claim 1, characterized in that: The carbon nanotubes are selected from at least one of single-walled carbon nanotubes and multi-walled carbon nanotubes.

4. The molecular sieve modification method according to claim 1, characterized in that: The conditions for the first ball milling are as follows: 30-55% volume of steel grinding balls are added to the ball milling jar, and the ball milling is performed at a rotation speed of 80-150 rpm / min for 10-60 minutes.

5. The molecular sieve modification method according to claim 1, characterized in that: The heating activation condition is heating at 100-150° C. for 12-48 hours.

6. The molecular sieve modification method according to claim 1, characterized in that: The weight ratio of the premix to the acrylic rubber powder is 1:2-3:

1.

7. The molecular sieve modification method according to claim 1, characterized in that: The conditions for the second ball milling are as follows: adding 25-45% volume of steel grinding balls into the ball milling jar, and ball milling at a rotation speed of 250-400 rpm / min for 3-12 hours.

8. A latex paint, characterized in that: The raw material components include emulsion, modified molecular sieve obtained by the molecular sieve modification method according to any one of claims 1 to 7, pigments, fillers and additives.

9. The latex paint according to claim 8, characterized in that: The weight proportion of the emulsion in the latex paint is 15-30%.

10. The latex paint according to claim 8, characterized in that: The weight proportion of the modified molecular sieve in the latex paint is 5-25%.

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