Inorganic water-hardening zero VOC environment-friendly wall material and preparation method thereof

Abstract

The application discloses an inorganic hydraulic zero-VOC environment-friendly wall material and a preparation method thereof. The wall material comprises the following raw materials in mass parts: cement 35-50 parts, redispersible emulsion powder 10-20 parts, mica powder 5-15 parts, zeolite powder 5-15 parts, nano titanium dioxide 5-15 parts, lightweight ceramic granules 5-15 parts, cellulose ether 0.5-2 parts, lignin fiber 2-8 parts and dispersing agent 0.5-2 parts. The zeolite powder is 4A grade zeolite powder with a particle size of 2-4 microns. The lightweight ceramic granules have a particle size of 4-6 mm and a pore size of 50-500 microns. The ratio of the sum of the mass parts of the zeolite powder and the nano titanium dioxide to the mass part of the lightweight ceramic granules is not greater than 2.5. The wall material has excellent crack resistance and sag resistance, can be used for wall coating construction with a thickness of 5-10 mm, and the raw materials used in the wall material are non-toxic and odorless, can adsorb and quickly decompose harmful pollutants in the environment, and can effectively purify the ambient air.

Description

Technical Field

[0001] This application belongs to the field of environmentally friendly coating technology, specifically relating to an inorganic hydraulic zero-VOC environmentally friendly wall material and its preparation method. Background Technology

[0002] Existing wall materials often produce harmful pollutants such as volatile organic compounds (VOCs), causing environmental pollution and even affecting people's health. With the overall improvement of living standards, modern people are paying more attention to health issues, thus placing higher demands on the environmental friendliness of wall materials. Therefore, there is an urgent need for a wall material that is non-toxic and can purify the air. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide an inorganic hydraulic zero-VOC environmentally friendly wall material and its preparation method. The wall material is non-toxic and can purify the ambient air, while also having excellent crack resistance and anti-sagging properties.

[0004] To achieve this objective, the present application adopts the following technical solution:

[0005] In a first aspect, this application provides an inorganic hydraulic zero-VOC environmentally friendly wall material, comprising the following raw materials by weight: 35-50 parts cement, 10-20 parts redispersible latex powder, 5-15 parts mica powder, 5-15 parts zeolite powder, 5-15 parts nano titanium dioxide, 5-15 parts lightweight ceramsite, 0.5-2 parts cellulose ether, 2-8 parts lignin fiber, and 0.5-2 parts dispersant; wherein the zeolite powder is grade 4A zeolite powder with a particle size of 2μm-4μm; the lightweight ceramsite has a particle size of 4mm-6mm and a pore size of 50μm-500μm; and the ratio of the sum of the weight parts of the zeolite powder and the nano titanium dioxide to the weight parts of the lightweight ceramsite is not greater than 2.5.

[0006] Optionally, the cement may be in the form of 43-46 parts, 43-47 parts, or 46-47 parts by weight.

[0007] Optionally, the mass fraction of zeolite powder is 8-9 parts, 8-10 parts, or 9-10 parts.

[0008] Optionally, the mass fraction of nano-titanium dioxide is 7 to 8 parts.

[0009] Optionally, the lignin fiber is 3 to 4 parts, 3 to 5 parts or 4 to 5 parts by weight.

[0010] Optionally, the ratio of the sum of the mass fractions of the zeolite powder and the nano-titanium dioxide to the mass fraction of the lightweight ceramsite is 2 to 2.5 or 2 to 2.25.

[0011] Optionally, the above wall materials also include raw materials: 1 to 5 parts of titanium dioxide.

[0012] Optionally, the cement is silicate cement, preferably with a strength grade of 52.5.

[0013] Optionally, the redispersible latex powder is vinyl acetate-ethylene copolymer powder (VAE powder) or ethylene-vinyl acetate copolymer powder (EVA powder).

[0014] Optionally, the mica powder has a particle size of 12μm to 18μm.

[0015] Optionally, the nano-titanium dioxide is anatase titanium dioxide.

[0016] Optionally, the cellulose ether is hydroxypropyl methylcellulose.

[0017] Optionally, the lignin fibers are lignin fibers with a length of 200 μm to 500 μm. Lignin fibers are organic fibers obtained from natural wood through chemical treatment.

[0018] Optionally, the dispersant is a polycarboxylate dispersant or a sodium polyacrylate dispersant.

[0019] Secondly, this application provides a method for preparing the aforementioned inorganic hydraulic zero-VOC environmentally friendly wall material, comprising: mixing the above raw materials in parts by mass to obtain a mixture, adding water at a material-to-water ratio of 1:(0.3-0.35), and mixing the mixture with water. Here, the material-to-water ratio refers to the mass ratio of the mixture to water.

[0020] The prepared wall material can be applied to the wall surface by brushing or rolling to obtain a wall coating with a thickness of 5mm to 10mm.

[0021] In the wall material of this application, cement is a hydraulic cementitious material and the main film-forming substance; redispersible latex powder is used to enhance the bonding performance; mica powder, fiber and lightweight ceramsite are used as fillers to enhance crack resistance and wall adhesion, and help to increase the construction thickness of the wall material; cellulose ether is used to enhance consistency and thixotropy; dispersant is used to reduce agglomeration and promote dispersion; titanium dioxide is used as a pigment.

[0022] In the wall material of this application, lightweight ceramsite serves as both a filler and, together with zeolite powder and nano-titanium dioxide, constitutes a purification functional component. Zeolite powder and lightweight ceramsite are porous materials used to adsorb harmful pollutants through physical adsorption; nano-titanium dioxide utilizes photocatalysis to degrade harmful pollutants. Simultaneously, the large-pore lightweight ceramic acts as a carrier for zeolite powder and nano-titanium dioxide, while the small-pore zeolite powder acts as a carrier for nano-titanium dioxide; the synergistic effect of these three components significantly enhances the air purification effect. Furthermore, the addition of lightweight ceramsite also endows the wall material with heat insulation and sound absorption functions.

[0023] Therefore, the wall material of this application has the following two significant advantages:

[0024] 1. It has excellent crack resistance and anti-sagging properties, and can be used for wall coatings with a thickness of 5mm to 10mm;

[0025] 2. All raw materials used are non-toxic and odorless, do not contain heavy metal ions, and do not produce toxic volatile substances such as VOCs. Furthermore, the purification components can adsorb and rapidly decompose harmful pollutants in the environment (such as toluene), effectively purifying the ambient air. Detailed Implementation

[0026] The technical solution of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0027] To further illustrate this application, the following examples and comparative examples provide a detailed description. The raw materials used in the following examples and comparative examples are all commercially available products, as detailed below:

[0028] Cement: Huaxin PI52.5 silicate cement; Redispersible latex powder: vinyl acetate-ethylene copolymer powder; Mica powder: particle size 12μm~18μm; Grade 4A zeolite powder: particle size 2μm~4μm, pore size approximately 0.4nm; Nano titanium dioxide: anatase titanium dioxide, particle size 20nm~30nm; Lightweight ceramsite: particle size 4mm~6mm, pore size 50μm~500μm, porosity 60%~75%; Cellulose ether: hydroxypropyl methylcellulose; Lignin fiber: length 200μm~500μm; Dispersant: 5040 type polycarboxylate dispersant.

[0029] Table 1 lists the raw materials used in the wall materials of Examples 1-3 and Comparative Examples 1-7 of this application and the mass fraction of each raw material.

[0030] Table 1. Raw materials and mass fractions of each raw material for the wall materials used in the examples and comparative examples.

[0031]

[0032] The wall materials in the examples and comparative examples were prepared using the same process: the raw materials shown in Table 1 were mixed in parts by mass to obtain a mixture, water was added at a material-to-water ratio of 1:0.3, and the mixture was stirred with water to obtain the wall material.

[0033] Performance tests were conducted on the wall materials used in the examples. Specifically, the wall materials of the examples and comparative examples were tested in accordance with the standards JC / T2083-2011 "Water-based Inorganic Dry Powder Interior Decoration Materials", GB / T 9779-2015 "Multi-layer Building Coatings", and GB18582-2008 "Limits of Harmful Substances in Interior Wall Coatings for Interior Decoration and Renovation Materials". All indicators of the wall materials of the examples and comparative examples met the standard requirements. The data of various indicators of the wall materials of Examples 1 to 3 are listed in Table 2 below.

[0034] Table 2. Data on various indicators of wall materials in Examples 1-3

[0035]

[0036] Air purification performance tests were conducted on the wall materials used in the embodiments and comparative examples. The test methods were as follows:

[0037] The wall material was evenly applied to the surface of a 100mm side wooden board. The board was placed inside a sealed glass box, with a water tank connected to the pressure balancing port at the bottom of the box to maintain the air pressure and pollutant gas concentration within the box during sampling. A convection fan was turned on to maintain uniform gas concentration throughout the box. Toluene was introduced until the initial concentration reached 200 μg / L, then the inlet was closed. The glass box was placed under illumination to begin the photodegradation process. The illumination conditions were: a UV fluorescent lamp with a wavelength of 340nm–400nm and a light intensity of 10mW / cm². Air samples were taken from the glass box using a micro-sampling pump, and gas chromatography was used to determine the changes in toluene content in the air, obtaining the following parameters:

[0038] 1. The time t for the complete consumption of toluene;

[0039] 2. The removal rate q of toluene after 1 h and 3 h of photodegradation, q = (C0 - C t ) / C0×100%, where C0 represents the initial concentration of toluene, C t This indicates the equilibrium concentration of toluene after 1 hour or 3 hours of photodegradation; concentration unit: μg / L.

[0040] The air purification performance test results of the wall materials in Examples 1-3 and Comparative Examples 1-7 are listed in Table 3. It should be noted that the longest photodegradation time in the above photodegradation experiments was set to 12 hours. The statement in Table 3 that toluene could not be completely consumed refers to the presence of toluene in the glass box after 12 hours of photodegradation.

[0041] Table 3. Air purification performance test results of wall materials in Examples 1-3 and Comparative Examples 1-7

[0042]

[0043] The air purification performance test results in Table 3 show that:

[0044] 1. The wall materials in Comparative Examples 1 and 5-6 did not contain nano-titanium dioxide; they relied solely on the physical adsorption properties of zeolite powder and / or lightweight ceramsite to purify toluene. Due to the upper limit of physical adsorption, the wall materials in Comparative Examples 1 and 5-6 could not completely consume toluene within the longest photodegradation time. However, the test results still show that the combination of zeolite powder and lightweight ceramsite can improve the toluene removal rate and promote purification speed.

[0045] 2. Nano-titanium dioxide was added to the wall materials of Comparative Examples 2 to 4. Nano-titanium dioxide degrades toluene through photocatalytic effect. Therefore, the wall materials of Comparative Examples 2 to 4 can completely consume toluene, but the toluene removal rate needs to be improved.

[0046] 3. When the purification functional component consists only of zeolite powder and / or lightweight ceramsite (see Comparative Examples 1 and 5-6), toluene cannot be completely consumed within the longest photodegradation time due to the upper limit of physical adsorption. When the purification functional component consists only of nano-titanium dioxide (see Comparative Example 4), or consists of one of zeolite powder, lightweight ceramsite, and nano-titanium dioxide (see Comparative Examples 2-3), toluene can be completely consumed, but the toluene removal rate needs to be improved. When the purification functional component simultaneously includes zeolite powder, lightweight ceramsite, and nano-titanium dioxide, and the ratio of the sum of the mass fractions of zeolite powder and nano-titanium dioxide to the mass fraction of lightweight ceramsite is not greater than 2.5 (see Examples 1-3), toluene can be completely consumed, and the toluene removal rate is significantly improved. However, when the ratio of the sum of the mass fractions of zeolite powder and nano-titanium dioxide to the mass fraction of lightweight ceramsite exceeds 2.5 (see Comparative Example 7), the improvement effect on the toluene removal rate is limited.

[0047] The inventors analyzed that the mechanism by which zeolite powder, lightweight ceramsite, and nano-titanium dioxide synergistically enhance the toluene removal rate is as follows: combining porous materials with physical adsorption properties with nano-titanium dioxide with photocatalytic properties allows the nano-titanium dioxide to remove the adsorption limit of the porous materials. The porous materials include lightweight ceramsite with large pores and zeolite powder with small pores. The small-sized zeolite powder fills the pores of the lightweight ceramsite, while the nano-titanium dioxide fills the pores of both the zeolite powder and the lightweight ceramsite, forming a complex microporous structure. This significantly increases the specific surface area, which helps to increase contact with harmful pollutants, thereby promoting the purification rate of harmful pollutants. The nano-titanium dioxide degrades harmful pollutants, creating pores in the microporous structure, further ensuring the purification rate and the sustainability of purification.

[0048] The wall material of this application, when the mass proportions of its raw materials are as follows: 35-50 parts cement, 10-20 parts redispersible latex powder, 5-15 parts mica powder, 5-15 parts zeolite powder, 5-15 parts nano titanium dioxide, 5-15 parts lightweight ceramsite, 0.5-2 parts cellulose ether, 2-8 parts lignin fiber, and 0.5-2 parts dispersant; this wall material is non-toxic and has excellent crack resistance and anti-sagging properties, meeting the requirements of standards JC / T2083-2011, GB / T 9779-2015, and GB18582-2008, and can be applied to form a wall coating with a thickness of 5mm-10mm.

[0049] When the purification functional components simultaneously include zeolite powder, lightweight ceramsite, and nano-titanium dioxide, the porous structure of zeolite powder and lightweight ceramsite can increase the specific surface area. Theoretically, the combination of zeolite powder and lightweight ceramsite with nano-titanium dioxide should promote the purification rate. However, in actual experiments, the synergistic effect of zeolite powder, lightweight ceramsite, and nano-titanium dioxide only occurs when the ratio of the sum of the mass fractions of zeolite powder and nano-titanium dioxide to the mass fraction of lightweight ceramsite falls within a specific range, and only then can the toluene removal rate be significantly improved.

[0050] Generally, the ratio should not exceed 2.5. When the ratio is greater than 2.5, for example, when the ratio is 2.75, the time to completely consume toluene is 7.3 hours. When the ratio is not greater than 2.5, for example, when the ratio is 2 to 2.5 or 2 to 2.25, the time to completely consume toluene is 5.2 hours to 5.6 hours. Compared with the aforementioned 7.3 hours, the time to completely consume toluene is reduced by about 2 hours, and the toluene removal rate is significantly improved.

[0051] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An inorganic hydraulic zero-VOC environmentally friendly wall material, characterized by: By weight, it includes the following raw materials: 35-50 parts cement, 10-20 parts redispersible latex powder, 5-15 parts mica powder, 5-15 parts zeolite powder, 5-15 parts nano titanium dioxide, 5-15 parts lightweight ceramsite, 0.5-2 parts cellulose ether, 2-8 parts lignin fiber, and 0.5-2 parts dispersant. The zeolite powder is grade 4A zeolite powder with a particle size of 2μm to 4μm; the lightweight ceramic particles have a particle size of 4mm to 6mm and a pore size of 50μm to 500μm; and the ratio of the sum of the mass fractions of the zeolite powder and the nano-titanium dioxide to the mass fraction of the lightweight ceramic particles is 2 to 2.

5.

2. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: It also includes raw materials: 1 to 5 parts of titanium dioxide.

3. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: The cement is silicate cement.

4. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: The redispersible latex powder is vinyl acetate-ethylene copolymer powder or ethylene-vinyl acetate copolymer powder.

5. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: The mica powder has a particle size of 12μm to 18μm.

6. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: The nano-titanium dioxide is anatase titanium dioxide.

7. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: The lignin fibers are lignin fibers with a length of 200μm to 500μm.

8. The inorganic hydraulic zero-VOC environmentally friendly wall material as described in claim 1, characterized in that: The dispersant is a polycarboxylate dispersant or a sodium polyacrylate dispersant.

9. The preparation method of the inorganic hydraulic zero-VOC environmentally friendly wall material according to any one of claims 1 to 8, characterized in that: Mix the raw materials according to their mass fractions to obtain a mixture. Add water at a material-to-water ratio of 1:(0.3-0.35) and mix the mixture with the water.

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