Waterproof inorganic mud coating capable of releasing negative ions and preparation method of waterproof inorganic mud coating

Abstract

The coating is prepared from the following raw materials in parts by weight: 28 to 50 parts of Portland cement powder, 10 to 40 parts of diatom powder, 1 to 10 parts of nano titanium dioxide, 1 to 5 parts of a curing agent, 1 to 3 parts of anion adding powder and 0.5 to 3 parts of methyl cellulose. The waterproof inorganic mud coating capable of releasing the negative ions can continuously release the negative ions, the safety is kept that the radiation value is smaller than 0.30 microsv / h, the negative ion release concentration can reach 10000 / cm < 3 > or above, and the concentration can be continuously kept for 5 years or above.

Description

Technical Field

[0001] The invention relates to the technical field of decorative coatings, in particular to a waterproof inorganic mud coating that releases negative ions and a preparation method thereof. Background Art

[0002] Market demand is constantly increasing, requiring coatings to be waterproof and durable, inorganic and VOC-free, and able to continuously release negative ions. The negative ion release concentration must meet 10,000 / cm 3 The above concentration can be maintained for more than 5 years, and the indoor environmental safety radiation value after painting is less than 0.30μsv / h (natural environmental radiation value 0.20-0.25μsv / h), and the painting is beautiful. The negative ion paint on the market currently does not have all the above properties.

[0003] The negative ion release concentration of common negative ion paints and negative ion muds cannot meet 10,000 / cm 3 The above concentrations are maintained for more than 5 years. Some safety radiation values ​​are higher than the natural environment value by 0.25μsv / h, and even reach 0.30μsv / h. According to Appendix B "Dose Limits and Surface Contamination Control Levels" in the "Basic Standards for Ionizing Radiation Protection and Radiation Source Safety" (GB18871-2002), the safety radiation value is within 5mSv per year for public use, and 100mSv / 5 years for nuclear power plant workers. Based on this, the maximum for the public is 0.57usv / h. For safety reasons, the indoor environment radiation value is usually controlled to be <0.30μsv / h. If the selection of the compatibility components of the negative ion waterproof inorganic mud coating and the reasonable ratio and preparation method cannot form a good dispersion system, the release concentration of excited negative ions will be low, the persistence will be poor, and the radiation value will be high. Summary of the invention

[0004] In view of the technical problems in the prior art of low concentration and poor persistence of negative ion release and high radiation value, the present application proposes a waterproof inorganic mud coating that releases negative ions and a preparation method thereof.

[0005] According to one aspect of the present invention, a waterproof inorganic mud coating that releases negative ions is proposed. The raw materials used include, by weight: 28-50 parts of silicate cement powder, 10-40 parts of diatom powder, 1-10 parts of nano titanium dioxide, 1-5 parts of curing agent, 1-3 parts of negative ion additive powder, and 0.5-3 parts of methyl cellulose.

[0006] Furthermore, the silicate cement powder and the diatom powder are in the form of white fine powder with a particle size greater than 200 meshes.

[0007] Furthermore, the preparation method of the silicate cement powder is: sintering kaolin, pure quartz sand, pure lime or chalk at a temperature of 1500° C. to 1600° C. to form clinker, and grinding the clinker with gypsum and limestone.

[0008] Furthermore, the curing agent is a water-based epoxy curing agent in liquid form.

[0009] Furthermore, the negative ion additive powder comprises tourmaline, crystal stone, hexachlorobenzene, neodymium oxide and thorium oxide, and has a particle size greater than 800 meshes.

[0010] Furthermore, the titanium dioxide powder includes anatase nano titanium dioxide powder.

[0011] Furthermore, the methyl cellulose is a white powdery nonionic cellulose ether.

[0012] According to a second aspect of the present invention, a method for preparing a waterproof inorganic mud coating that releases negative ions is provided, comprising the following steps:

[0013] S1: Mix the powder components except the curing agent according to proportion, stir evenly, and weigh the curing agent for independent packaging;

[0014] S2: Mix the powder component and water in proportion, shake until a uniform emulsion is formed, add the curing agent, and stir until all are uniformly mixed.

[0015] Furthermore, the mass ratio of the powder component to water is 5:3.

[0016] Furthermore, the powder component is packaged using waterproof materials, and the curing agent is packaged using sealed barrels.

[0017] Beneficial effects of the present invention:

[0018] 1. The present application proposes a negative ion releasing waterproof inorganic mud coating which can continuously release negative ions and maintain safety at a radiation value of less than 0.30 μsv / h and a negative ion release concentration of up to 10,000 / cm 3 Above, the concentration can be maintained for more than 5 years;

[0019] 2. The present application proposes a waterproof inorganic mud coating that releases negative ions and a preparation method thereof. The coating is in powder form. When used, the powder is added with water to be adjusted to an emulsion state and then a curing agent is added. The preparation method is simple and easy to operate. The method of use can be spraying or rolling. The coating is beautiful, waterproof and durable. The material does not contain VOC and is safe and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and are used together with the description to explain the principles of the present invention. It will be easy to recognize other embodiments and many expected advantages of the embodiments because they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale with each other. The same reference numerals refer to corresponding similar parts.

[0021] Figure 1 A schematic flow chart of a preparation method according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0022] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It should also be noted that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] Example 1

[0025] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0026] 30 parts of silicate cement powder, 38 parts of diatom powder, 3 parts of nano titanium dioxide, 2 parts of curing agent, 1.5 parts of negative ion additive powder and 1 part of methyl cellulose.

[0027] like Figure 1 As shown, the preparation method of the waterproof inorganic mud coating releasing negative ions in practice comprises the following steps:

[0028] S1: Mix and stir the powdered components in proportion, weigh the curing agent and package it independently in a sealed barrel;

[0029] S2: When implementing the construction, first pour the powder component into a 20L bucket, take tap water at a weight of 60% of the weight of the powder component, add the tap water to the powder twice, use an electric mixer to shake for 10 minutes until it becomes a uniform emulsion, then add the curing agent and continue stirring until everything is mixed evenly.

[0030] Example 2

[0031] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0032] 35 parts of silicate cement powder, 35 parts of diatom powder, 6 parts of nano titanium dioxide, 3 parts of curing agent, 1 part of negative ion additive powder and 2 parts of methyl cellulose.

[0033] The preparation method of the waterproof inorganic mud coating that releases negative ions in this embodiment is the same as the steps in Example 1.

[0034] Example 3

[0035] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0036] 40 parts of silicate cement powder, 30 parts of diatom powder, 6 parts of nano titanium dioxide, 4 parts of curing agent, 2 parts of negative ion additive powder and 2 parts of methyl cellulose.

[0037] The preparation method of the waterproof inorganic mud coating that releases negative ions in this embodiment is the same as the steps in Example 1.

[0038] Example 4

[0039] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0040] 45 parts of silicate cement powder, 25 parts of diatom powder, 8 parts of nano titanium dioxide, 4 parts of curing agent, 2 parts of negative ion additive powder and 1 part of methyl cellulose.

[0041] The preparation method of the waterproof inorganic mud coating that releases negative ions in this embodiment is the same as the steps in Example 1.

[0042] Example 5

[0043] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0044] 48 parts of silicate cement powder, 20 parts of diatom powder, 8 parts of nano titanium dioxide, 4 parts of curing agent, 2 parts of negative ion additive powder and 2 parts of methyl cellulose.

[0045] The preparation method of the waterproof inorganic mud coating that releases negative ions in this embodiment is the same as the steps in Example 1.

[0046] Example 6

[0047] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0048] 28 parts of silicate cement powder, 15 parts of diatom powder, 1 part of nano titanium dioxide, 1 part of curing agent, 1 part of negative ion additive powder and 0.5 part of methyl cellulose.

[0049] The preparation method of the waterproof inorganic mud coating that releases negative ions in this embodiment is the same as the steps in Example 1.

[0050] Example 7

[0051] The waterproof inorganic mud coating for releasing negative ions in this embodiment is made of the following raw materials in parts by weight:

[0052] 50 parts of silicate cement powder, 10 parts of diatom powder, 10 parts of nano titanium dioxide, 5 parts of curing agent, 3 parts of negative ion additive powder and 3 parts of methyl cellulose.

[0053] The preparation method of the waterproof inorganic mud coating that releases negative ions in this embodiment is the same as the steps in Example 1.

[0054] Comparative Example 1:

[0055] The negative ion releasing waterproof inorganic mud coating in this comparative example is made of the following raw materials in parts by weight:

[0056] 27 parts of silicate cement powder, 9 parts of diatom powder, 0.5 parts of nano titanium dioxide, 0.5 parts of curing agent, 0.5 parts of negative ion additive powder and 0.4 parts of methyl cellulose.

[0057] The preparation method of the negative ion releasing waterproof inorganic mud coating in this comparative example is the same as that in the above-mentioned Example 1.

[0058] Comparative Example 2:

[0059] The negative ion releasing waterproof inorganic mud coating in this comparative example is made of the following raw materials in parts by weight:

[0060] 51 parts of silicate cement powder, 41 parts of diatom powder, 11 parts of nano titanium dioxide, 6 parts of curing agent, 4 parts of negative ion additive powder and 4 parts of methyl cellulose.

[0061] The preparation method of the negative ion releasing waterproof inorganic mud coating in this comparative example is the same as that in the above-mentioned Example 1.

[0062] Comparative Examples 3-5 were prepared respectively using Examples 1-3 of a microcement coating and a preparation method thereof with publication number CN118006150A.

[0063] Comparative Example 3

[0064] Example 1 of a microcement coating and its preparation method cited from CN118006150A:

[0065] Provided is a method for preparing a microcement coating, comprising the following steps:

[0066] S1. Preparation of composite emulsion

[0067] The isocyanate propyl triethoxysilane and toluene are mixed uniformly in a weight ratio of 2:1 to obtain an isocyanate propyl triethoxysilane solution for later use;

[0068] Weigh: 50 g of butyl methacrylate, 20 g of methyl methacrylate, 10 g of ethyl acrylate, 260 mL of toluene and 1 g of azobisisobutyronitrile, add them into a nitrogen-protected reactor and stir, raise the temperature of the reactor to 80° C., keep the temperature for 4 h, lower the temperature of the reactor to room temperature, drop 20 g of isocyanatepropyltriethoxysilane solution into the reactor, and after the dropwise addition is complete, stir and react for 2 h at room temperature, raise the temperature of the reactor to 80° C., and evaporate the solvent under reduced pressure to obtain a polyolefin;

[0069] Weigh: 30 g of glyceryl stearate, 10 g of polyethylene glycol 4000, 20 g of Tween-80, 207 g of Span and 1000 mL of purified water, add into a reaction kettle and stir evenly, adjust the pH of the reaction kettle to 7, and obtain an emulsion;

[0070] Weigh: 1000 g of the emulsion is added into a reactor and stirred. At room temperature, 200 g of polyolefin is added into the reactor in batches and stirred until the system is dissolved to obtain a composite emulsion.

[0071] S2. Preparation of modified calcium powder

[0072] Weigh: 40 g of anhydrous ethanol, 30 g of tetraethyl orthosilicate and 500 mL of purified water, add them into a reactor and stir, lower the temperature of the reactor to 20°C, add hydrochloric acid into the reactor, adjust the pH of the system to 2, keep warm and stir for 8 hours, add ammonia water into the reactor, adjust the pH of the system to 7, raise the temperature of the reactor to 55°C, and evaporate the solvent under reduced pressure to obtain silica gel;

[0073] Weigh: 40 g of silica gel powder, 120 g of silica gel, 20 g of calcium oxide, 1200 mL of deionized water and 0.6 g of dodecylphenol polyoxyethylene ether and add them into a ball mill, set the ball-to-material ratio of the ball mill to 3:1, the abrasive is zirconia balls with a particle size of 3-5 mm, the speed of the ball mill is set to 100 r / min, and ball mill for 3 h to obtain a mixed slurry;

[0074] The mixed slurry was transferred to a stainless steel autoclave, the temperature of the autoclave was raised to 190°C, and the temperature was kept for 12 hours. The temperature of the autoclave was lowered to room temperature, the autoclave was opened, and the reaction system in the autoclave was transferred to an oven, the oven temperature was set to 190°C, and the mixture was kept dry to constant weight, lowered to room temperature, ground, and passed through a 100-mesh sieve to obtain porous calcium powder;

[0075] Weigh: 400 g of porous calcium powder and 100 g of sodium methyl silicate, add them into a three-dimensional mixer, and mix them three-dimensionally for 30 minutes to obtain modified calcium powder.

[0076] S3. Preparation of composite calcium silicate

[0077] The calcium silicate powder was crushed by a jet mill and passed through a 600-mesh sieve to obtain calcium silicate powder;

[0078] Weigh: 60 g of calcium silicate powder, 200 mL of purified water, 300 mL of anhydrous ethanol and 40 g of 25 wt% ammonia water, add them into a reactor, ultrasonically disperse for 60 min, raise the temperature of the reactor to micro-reflux of the system, add 40 g of 3-aminopropyltriethoxysilane into the reactor, keep the reaction for 3 h, lower the temperature of the reactor to room temperature, filter, wash the filter cake with purified water until it is neutral and then drain, transfer the filter cake to a drying oven at a temperature of 55° C., and dry it to constant weight to obtain modified calcium silicate;

[0079] Weigh: 60 g of modified calcium silicate and 360 mL of N,N-dimethylformamide, add them to the reactor, ultrasonically disperse for 40 minutes, add 40 g of isocyanatepropyltriethoxysilane dropwise to the reactor, and after the addition is completed, the temperature of the reactor is raised to 50°C, and the reaction is kept warm for 5 hours. The temperature of the reactor is lowered to room temperature, filtered, the filter cake is washed three times with anhydrous ethanol and then dried, and the filter cake is transferred to a drying oven at a temperature of 50°C, and vacuum dried to constant weight to obtain composite calcium silicate.

[0080] S4. Preparation of composite fillers

[0081] Weigh: 100 g of polyvinyl alcohol, 400 mL of purified water and 2 g of sodium dodecyl sulfate and add them into a reactor. Raise the temperature of the reactor to 65°C and stir until the system is dissolved to obtain a coating solution.

[0082] Weigh: 50g of composite calcium silicate and 30g of modified calcium powder and add them into a mixer, set the temperature of the mixer to 95°C and the speed to 600r / min, add 150mL of coating liquid into the mixer in the form of spray, after the coating liquid is added, keep warm for 2h, lower the temperature of the mixer to room temperature, mix for 60min, and obtain a composite filler.

[0083] S5. Preparation of microcement coating

[0084] Ethylenediaminetetraacetic acid, hydroxyethylidene diphosphonic acid and 2-phospho-1,2,4-tricarboxylic acid butane are mixed uniformly in a weight ratio of 2:1:1 to obtain a complexing agent for later use;

[0085] Weigh: 500 g of silicate cement and 5000 mL of purified water, add them to a stirring kettle, stir for 50 min, let it stand and soak for 2 h, separate the liquids, remove the supernatant, add 300 g of composite filler, 600 g of composite emulsion and 5 g of complexing agent to the stirring kettle, stir evenly, add purified water to the reactor, adjust the viscosity of the system to 4000 mPa·s, and obtain a microcement coating.

[0086] Comparative Example 4

[0087] Cited from Example 2 of a microcement coating and a preparation method thereof in CN118006150A:

[0088] This embodiment provides a method for preparing a microcement coating, comprising the following steps:

[0089] S1. Preparation of composite emulsion

[0090] The isocyanate propyl triethoxysilane and toluene are mixed uniformly in a weight ratio of 2:1 to obtain an isocyanate propyl triethoxysilane solution for later use;

[0091] Weigh: 50 g of butyl methacrylate, 20 g of methyl methacrylate, 10 g of ethoxyethyl acrylate, 260 mL of toluene and 1 g of azobisisobutyronitrile, add them into a nitrogen-protected reactor and stir, raise the temperature of the reactor to 83°C, keep the reaction for 5 hours, lower the temperature of the reactor to room temperature, drop 20 g of isocyanatepropyltriethoxysilane solution into the reactor, and after the dropwise addition is complete, stir and react for 2.5 hours at room temperature, raise the temperature of the reactor to 83°C, and evaporate the solvent under reduced pressure to obtain a polyolefin;

[0092] Weigh: 30 g of glyceryl stearate, 10 g of polyethylene glycol 4000, 20 g of Tween-80, 207 g of Span and 1000 mL of purified water, add into a reaction kettle and stir evenly, adjust the pH of the reaction kettle to 7.5, and obtain an emulsion;

[0093] Weigh: 1000 g of the emulsion is added into a reactor and stirred. At room temperature, 200 g of polyolefin is added into the reactor in batches and stirred until the system is dissolved to obtain a composite emulsion.

[0094] S2. Preparation of modified calcium powder

[0095] Weigh: 40 g of anhydrous ethanol, 30 g of tetraethyl orthosilicate and 500 mL of purified water, add them into a reactor and stir, lower the temperature of the reactor to 23°C, add hydrochloric acid into the reactor, adjust the pH of the system to 2.5, keep warm and stir for 9 hours, add ammonia water into the reactor, adjust the pH of the system to 7, raise the temperature of the reactor to 57°C, and evaporate the solvent under reduced pressure to obtain silica gel;

[0096] Weigh: 40 g of silica gel powder, 120 g of silica gel, 20 g of calcium oxide, 1200 mL of deionized water and 0.6 g of dodecylphenol polyoxyethylene ether and add them into a ball mill, set the ball-to-material ratio of the ball mill to 3:1, the abrasive is zirconia balls with a particle size of 3-5 mm, the speed of the ball mill is set to 100 r / min, and ball mill for 3.5 h to obtain a mixed slurry;

[0097] The mixed slurry was transferred to a stainless steel autoclave, the temperature of the autoclave was raised to 195°C, and the temperature was kept for 13 hours. The temperature of the autoclave was lowered to room temperature, the autoclave was opened, and the reaction system in the autoclave was transferred to an oven, the oven temperature was set to 195°C, and the mixture was kept dry to constant weight, lowered to room temperature, ground, and passed through a 100-mesh sieve to obtain porous calcium powder;

[0098] Weigh: 400 g of porous calcium powder and 100 g of sodium methyl silicate, add them into a three-dimensional mixer, and mix them three-dimensionally for 40 minutes to obtain modified calcium powder.

[0099] S3. Preparation of composite calcium silicate

[0100] The calcium silicate powder was crushed by a jet mill and passed through a 600-mesh sieve to obtain calcium silicate powder;

[0101] Weigh: 60 g of calcium silicate powder, 200 mL of purified water, 300 mL of anhydrous ethanol and 40 g of 25 wt% ammonia water, add them into a reactor, ultrasonically disperse for 70 min, raise the temperature of the reactor to micro-reflux of the system, add 40 g of 3-aminopropyltriethoxysilane into the reactor, keep the reaction for 4 h, lower the temperature of the reactor to room temperature, filter, wash the filter cake with purified water until it is neutral and then drain, transfer the filter cake to a drying oven at a temperature of 60° C., and dry it to constant weight to obtain modified calcium silicate;

[0102] Weigh: 60 g of modified calcium silicate and 360 mL of N,N-dimethylformamide, add them to the reactor, ultrasonically disperse for 50 minutes, add 40 g of isocyanatepropyltriethoxysilane dropwise to the reactor, and after the addition is completed, the temperature of the reactor is raised to 55°C, and the reaction is kept warm for 6 hours. The temperature of the reactor is lowered to room temperature, filtered, the filter cake is washed three times with anhydrous ethanol and then dried, and the filter cake is transferred to a drying oven at a temperature of 55°C, and vacuum dried to constant weight to obtain composite calcium silicate.

[0103] S4. Preparation of composite fillers

[0104] Weigh: 100 g of polyvinyl alcohol, 400 mL of purified water and 2 g of sodium dodecyl sulfate and add them into a reactor. Raise the temperature of the reactor to 70°C and stir until the system is dissolved to obtain a coating solution.

[0105] Weigh: 50g of composite calcium silicate and 30g of modified calcium powder and add them into a mixer, set the temperature of the mixer to 100°C and the speed to 650r / min, add 150mL of coating liquid into the mixer in the form of spray, after the coating liquid is added, keep warm for 2.5h, lower the temperature of the mixer to room temperature, mix for 70min, and obtain a composite filler.

[0106] S5. Preparation of microcement coating

[0107] Ethylenediaminetetraacetic acid, hydroxyethylidene diphosphonic acid and 2-phospho-1,2,4-tricarboxylic acid butane are mixed uniformly in a weight ratio of 2:1:1 to obtain a complexing agent for later use;

[0108] Weigh: 550 g of silicate cement and 5500 mL of purified water are added to a stirring kettle, stirred for 55 min, allowed to stand and soak for 2.5 h, separated, the supernatant is removed, 350 g of composite filler, 700 g of composite emulsion and 8 g of complexing agent are added to the stirring kettle, stirred evenly, purified water is added to the reactor, the viscosity of the system is adjusted to 4500 mPa·s, and a microcement coating is obtained.

[0109] Comparative Example 5

[0110] Cited from Example 3 of a microcement coating and its preparation method in CN118006150A:

[0111] This embodiment provides a method for preparing a microcement coating, comprising the following steps:

[0112] S1. Preparation of composite emulsion

[0113] The isocyanate propyl triethoxysilane and toluene are mixed uniformly in a weight ratio of 2:1 to obtain an isocyanate propyl triethoxysilane solution for later use;

[0114] Weigh: 50 g of butyl methacrylate, 20 g of methyl methacrylate, 10 g of ethoxyethyl allylate, 260 mL of toluene and 1 g of azobisisobutyronitrile, add them into a nitrogen-protected reactor and stir, raise the temperature of the reactor to 86° C., keep the temperature for 6 h, lower the temperature of the reactor to room temperature, drop 20 g of isocyanatepropyltriethoxysilane solution into the reactor, and after the dropwise addition is complete, stir and react for 3 h at room temperature, raise the temperature of the reactor to 86° C., and evaporate the solvent under reduced pressure to obtain a polyolefin;

[0115] Weigh: 30 g of glyceryl stearate, 10 g of polyethylene glycol 4000, 20 g of Tween-80, 207 g of Span and 1000 mL of purified water, add into a reaction kettle and stir evenly, adjust the pH of the reaction kettle to 8, and obtain an emulsion;

[0116] Weigh: 1000 g of the emulsion is added into a reactor and stirred. At room temperature, 200 g of polyolefin is added into the reactor in batches and stirred until the system is dissolved to obtain a composite emulsion.

[0117] S2. Preparation of modified calcium powder

[0118] Weigh: 40 g of anhydrous ethanol, 30 g of tetraethyl orthosilicate and 500 mL of purified water, add them into a reactor and stir, lower the temperature of the reactor to 25°C, add hydrochloric acid into the reactor, adjust the pH of the system to 3, keep warm and stir for 10 hours, add ammonia water into the reactor, adjust the pH of the system to 7, raise the temperature of the reactor to 60°C, and evaporate the solvent under reduced pressure to obtain silica gel;

[0119] Weigh: 40 g of silica gel powder, 120 g of silica gel, 20 g of calcium oxide, 1200 mL of deionized water and 0.6 g of dodecylphenol polyoxyethylene ether and add them into a ball mill, set the ball-to-material ratio of the ball mill to 3:1, the abrasive is zirconia balls with a particle size of 3-5 mm, the speed of the ball mill is set to 100 r / min, and ball mill for 4 h to obtain a mixed slurry;

[0120] The mixed slurry was transferred to a stainless steel autoclave, the temperature of the autoclave was raised to 200°C, and the temperature was kept for 14 hours. The temperature of the autoclave was lowered to room temperature, the autoclave was opened, and the reaction system in the autoclave was transferred to an oven, the oven temperature was set to 200°C, and the mixture was kept dry to constant weight, and then the mixture was lowered to room temperature, ground, and passed through a 100-mesh sieve to obtain porous calcium powder;

[0121] Weigh: 400 g of porous calcium powder and 100 g of sodium methyl silicate, add them into a three-dimensional mixer, and mix them three-dimensionally for 50 minutes to obtain modified calcium powder.

[0122] S3. Preparation of composite calcium silicate

[0123] The calcium silicate powder was crushed by a jet mill and passed through a 600-mesh sieve to obtain calcium silicate powder;

[0124] Weigh: 60 g of calcium silicate powder, 200 mL of purified water, 300 mL of anhydrous ethanol and 40 g of 25 wt% ammonia water, add them into a reactor, ultrasonically disperse for 80 min, raise the temperature of the reactor to micro-reflux of the system, add 40 g of 3-aminopropyltriethoxysilane into the reactor, keep the reaction for 5 h, lower the temperature of the reactor to room temperature, filter, wash the filter cake with purified water until it is neutral and then drain, transfer the filter cake to a drying oven at a temperature of 65° C., and dry it to constant weight to obtain modified calcium silicate;

[0125] Weigh: 60 g of modified calcium silicate and 360 mL of N,N-dimethylformamide, add them to the reactor, ultrasonically disperse for 60 minutes, add 40 g of isocyanatepropyltriethoxysilane dropwise to the reactor, and after the addition is completed, the temperature of the reactor is raised to 60°C, and the reaction is kept warm for 7 hours. The temperature of the reactor is lowered to room temperature, filtered, the filter cake is washed three times with anhydrous ethanol and then dried, and the filter cake is transferred to a drying oven at a temperature of 60°C and vacuum dried to constant weight to obtain composite calcium silicate.

[0126] S4. Preparation of composite fillers

[0127] Weigh: 100 g of polyvinyl alcohol, 400 mL of purified water and 2 g of sodium dodecyl sulfate and add them into a reactor. Raise the temperature of the reactor to 75°C and stir until the system is dissolved to obtain a coating solution.

[0128] Weigh: 50g of composite calcium silicate and 30g of modified calcium powder and add them into a mixer, set the temperature of the mixer to 105°C and the speed to 700r / min, add 150mL of coating liquid into the mixer in the form of spray, after the coating liquid is added, keep warm for 3h, lower the temperature of the mixer to room temperature, mix for 80min, and obtain a composite filler.

[0129] S5. Preparation of microcement coating

[0130] Ethylenediaminetetraacetic acid, hydroxyethylidene diphosphonic acid and 2-phospho-1,2,4-tricarboxylic acid butane are mixed uniformly in a weight ratio of 2:1:1 to obtain a complexing agent for later use;

[0131] Weigh: 600 g of silicate cement and 6000 mL of purified water, add them to a stirring kettle, stir for 60 min, let it stand and soak for 3 h, separate the liquids, remove the supernatant, add 400 g of composite filler, 800 g of composite emulsion and 12 g of complexing agent to the stirring kettle, stir evenly, add purified water to the reactor, adjust the viscosity of the system to 5000 mPa·s, and obtain a microcement coating.

[0132] The weight statistics of the components of each embodiment and comparative example of the present application are shown in Table 1 and Table 2 below:

[0133] Table 1 Statistical table of weight of each component in the embodiment

[0134]

[0135]

[0136] Table 2 Weight statistics of each component in comparative example

[0137]

[0138] The present invention is tested with reference to JC / T2110-2012 "Indoor Air Ion Concentration Test Method" and Q / WYKJ002-2020 enterprise standards. Specifically, the negative ion-releasing waterproof inorganic mud coating obtained by the above-mentioned embodiment and comparative example is adopted. 12 new white gypsum boards with a length of 1 meter and a width of 1 meter are prepared and marked, and the coatings of the embodiment and comparative example are sprayed respectively, and the spraying amount is the normal wall spraying amount, 200 grams / square, that is, 200 grams are sprayed on each board. After spraying, let it stand for 1 hour until the sprayed board is dry, put it on the bottom surface of a glass box with a length of 1.5 meters, a width of 1.5 meters, and a height of 1.5 meters, cover it with a top plate, and open a circular hole with a diameter of 5 cm at a height of 1 meter from the bottom surface of the side of the glass box. The detection port of the negative ion detector is placed in this circular hole to measure the negative ion concentration value, and the radiation value measured at a distance of 10 cm from the sprayed board, as well as waterproofness and adhesion. The waterproofness test was conducted by spraying 100ml of tap water on each board and letting it stand for 2 minutes, then wiping the surface water with a paper towel, and after 1 minute, laying white toilet paper on it and observing the area of ​​the paper surface that was soaked. The adhesion test was conducted by selecting an area of ​​10×20cm on each board, brushing it from top to bottom 10 times with a nylon brush, and observing whether there was any paint that fell off on the nylon brush. The test results are shown in Tables 3 and 4.

[0139] Table 3 Statistical table of test results of coatings in various embodiments

[0140]

[0141] Table 4 Statistics of test results of each comparative coating

[0142]

[0143] By comparing Table 3 and Table 4, it can be seen that the negative ion waterproof inorganic mud coating prepared by the embodiment of the present invention can achieve a negative ion release concentration of 10000 / cm 3 Among them, although the negative ion release concentration of the negative ion waterproof inorganic mud coating prepared in Comparative Example 2 is similar to that in Example 7, its radiation value reaches a high value of 0.30μsv / h, and the cost is slightly increased.

[0144] After the sprayed gypsum board samples and control samples were stored for one year, the negative ion concentration values ​​were tested again using the same testing method as above. The test results are shown in Tables 5 and 6:

[0145] Table 5 Statistical table of test results of sample implementation with retention time of 1 year

[0146]

[0147] Table 6 Statistical table of test results of comparative samples retained for 1 year

[0148]

[0149] After the sprayed gypsum board samples and control samples were stored for 5 years, the negative ion concentration values ​​were tested again using the same detection method as above. The test results are shown in Tables 7 and 8 below.

[0150] Table 7 Statistical table of test results of sample implementation with retention time of 5 years

[0151]

[0152] Table 8 Statistical table of test results of comparative samples retained for 5 years

[0153]

[0154]

[0155] By comparing Tables 3, 4, 5, 6, 7 and 8 above, it can be seen that the negative ion waterproof inorganic mud coating prepared by the embodiments of the present invention not only has a higher negative ion release concentration, but also the negative ion concentration can be maintained continuously for more than 5 years, and the radioactivity is less than 0.30μsv / h, which has higher safety.

[0156] The invention discloses a waterproof inorganic mud coating that releases negative ions. The coating comprises silicate cement powder, diatom powder, nano titanium dioxide, waterborne epoxy curing agent, negative ion additive powder and other ingredients with excellent performance. The coating meets the requirements of waterproof and durable, inorganic and VOC-free, and sustainable release of negative ions. The negative ion release concentration must meet the requirement of 10,000 / cm 3 The above concentration can be maintained for more than 5 years. The indoor environmental safety radiation value after painting is less than 0.30μsv / h, and the coating film is beautiful and firm.

[0157] The above describes the specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0158] In the description of the present application, it should be understood that the terms "upper", "lower", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The wording 'comprising' does not exclude the presence of elements or steps not listed in the claims. The wording 'one' or 'an' preceding an element does not exclude the presence of a plurality of such elements. The simple fact that certain measures are recorded in mutually different dependent claims does not indicate that a combination of these measures cannot be used for improvement. Any reference symbols in the claims should not be interpreted as limiting the scope.

Claims

1. A waterproof inorganic mud coating that releases negative ions, characterized in that: The raw materials used include, by weight: 28-50 parts of silicate cement powder, 10-40 parts of diatom powder, 1-10 parts of nano titanium dioxide, 1-5 parts of curing agent, 1-3 parts of negative ion additive powder and 0.5-3 parts of methyl cellulose.

2. A waterproof inorganic mud coating for releasing negative ions according to claim 1, characterized in that: The silicate cement powder and the diatom powder are in the form of white fine powder with a particle size greater than 200 meshes.

3. A waterproof inorganic mud coating for releasing negative ions according to claim 2, characterized in that: The preparation method of the silicate cement powder is as follows: kaolin, pure quartz sand, pure lime or chalk are fired at a temperature of 1500° C. to 1600° C. to form clinker, and the clinker is ground with gypsum and limestone.

4. The waterproof inorganic mud coating for releasing negative ions according to claim 1, characterized in that: The curing agent is a water-based epoxy curing agent in liquid form.

5. The waterproof inorganic mud coating for releasing negative ions according to claim 1, characterized in that: The negative ion additive powder comprises tourmaline, crystal stone, hexachlorobenzene, neodymium oxide and thorium oxide, and has a particle size greater than 800 meshes.

6. The waterproof inorganic mud coating for releasing negative ions according to claim 1, characterized in that: The titanium dioxide includes anatase nano titanium dioxide powder.

7. The waterproof inorganic mud coating for releasing negative ions according to claim 1, characterized in that: The methyl cellulose is a white powdery nonionic cellulose ether.

8. A method for preparing a waterproof inorganic mud coating that releases negative ions, characterized in that: The following steps are involved: S1: Mix the powder components except the curing agent according to proportion, stir evenly, and weigh the curing agent for independent packaging; S2: Mix the powder component and water in proportion, shake until a uniform emulsion is formed, add the curing agent, and stir until all are uniformly mixed.

9. The method for preparing a waterproof inorganic mud coating that releases negative ions according to claim 8, characterized in that: The mass ratio of the powder component to water is 5:

3.

10. The method for preparing a waterproof inorganic mud coating that releases negative ions according to claim 8, characterized in that: The powder component is packaged with a waterproof material, and the curing agent is packaged with a sealed barrel.

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