Rammed earth paint and preparation method and application thereof

Abstract

The present invention relates to the technical field of building decoration materials, and specifically discloses a rammed earth paint, which comprises the following raw materials in parts by weight: 20-30 parts of soil, 20-30 parts of cement, 40-50 parts of sand, 0.3-0.4 parts of cellulose, 0.3-0.5 parts of wood fiber, 0.2-0.3 parts of water reducer, 5-8 parts of side chain polyether modified amino silicone, 0.3-0.5 parts of curing agent, 0.5-1 parts of starch phosphate, and 18-30 parts of water. The rammed earth paint of the present invention mainly uses soil, cement, and sand as main materials, and is modified by adding cellulose, wood fiber, side chain polyether modified amino silicone, starch phosphate, etc., which can improve the combination of soil and cement in the rammed earth paint, improve the uniformity and stability of the rammed earth paint, enhance the flexibility and strength of the rammed earth system, and avoid cracking, falling off, and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of building decoration materials, and particularly relates to rammed earth paint and a preparation method and application thereof. Background Art

[0002] Rammed earth paint is a building material whose main component is soil. Soil is a ubiquitous, low-cost, and sustainable resource. Using it in the construction of industrial projects can minimize the impact on the environment. Existing solid rammed earth walls have problems such as high construction difficulty, long construction period, and large space occupation. Compared with solid rammed earth walls, rammed earth paint is more convenient and quick to construct, greatly reducing the construction period and saving costs. Rammed earth paint has environmental protection characteristics and also has a retro and natural decorative effect. It is mainly used in the development of rural tourism and the interior and exterior wall decoration of landscape buildings. In recent years, with the large-scale renovation of tourism real estate and rural areas, the rammed earth style has returned to architectural decoration. The rammed earth decorative layer is formed by brushing rammed earth paint on the surface of the exterior wall. Since the rammed earth decorative layer is exposed to the air, it must withstand the test of climate and is more susceptible to wind erosion, water erosion, and disturbances caused by human activities. It must have high compressive strength, weather resistance, crack resistance, and erosion resistance to avoid damage.

[0003] Traditional rammed earth paint uses emulsion as a film-forming substance, and its disadvantages are that it cannot be applied thickly, the effect is not realistic, and it cannot achieve the kind of environmentally friendly and rough simulation effect. Using cement as a binder will not produce harmful substances, is green and environmentally friendly, and can be applied thickly, which can make the effect more realistic. However, in actual application, using cement as a binder and mixing it with soil as rammed earth paint to form a rammed earth layer on the exterior wall is prone to cracking problems. In addition, the strength of the rammed earth layer material itself is poor. It is a brittle material under dry conditions, which is characterized by poor adhesion, powder shedding, and low strength. Summary of the invention

[0004] To achieve the above-mentioned purpose, the present invention provides a rammed earth paint, which comprises the following raw materials in parts by weight: 20-30 parts of soil, 20-30 parts of cement, 40-50 parts of sand, 0.3-0.4 parts of cellulose, 0.3-0.5 parts of wood fiber, 0.2-0.3 parts of water reducer, 5-8 parts of side chain polyether modified amino silicone, 0.3-0.5 parts of curing agent, 0.5-1 parts of starch phosphate, and 18-30 parts of water.

[0005] The rammed earth paint of the present invention mainly uses soil, cement, and sand as main materials, adds wood fiber, and the wood fiber is dispersed in the soil, which is beneficial to the network structure and improves the strength of the rammed earth layer. The side chain polyether modified amino silicone is added, and the silicone has a wetting and dispersing effect. Further, the ether group has hydrophilicity, and a layer of water film is formed on the surface of cement particles through hydrogen bonding and water molecules, which enhances fluidity. The amino group acts on the hydroxyl group on the surface of the soil material, which is beneficial to improve the mixed dispersion of the soil material and cement, improve the uniformity and stability of the rammed earth paint, and is beneficial to the combination of the soil material and cement to improve the strength and avoid cracking problems. Adding starch phosphate can effectively avoid the cracking problem of rammed earth. The present invention improves the adhesion of the rammed earth paint by optimizing the components of the rammed earth paint, improves the flexibility and strength of the rammed earth system, and avoids cracking, falling off, and the like.

[0006] Preferably, in the above-mentioned rammed earth paint, the rammed earth paint comprises the following raw materials in parts by weight: 25 parts of soil, 22 parts of cement, 45 parts of sand, 0.35 parts of cellulose, 0.4 parts of wood fiber, 0.25 parts of water reducer, 6.5 parts of side chain polyether modified amino silicone, 0.4 parts of curing agent, 0.8 parts of starch phosphate, and 22 parts of water.

[0007] Preferably, in the above-mentioned rammed earth paint, the water reducer is a sulfonated melamine water reducer.

[0008] Preferably, in the rammed earth paint, the curing agent is composed of aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide. The curing agent can promote the solidification of the soil material and also improve the strength.

[0009] Preferably, in the above-mentioned rammed earth paint, the mass ratio of the aluminum sulfate, sodium silicate and quaternary ammonium amphoteric polyacrylamide is 20~30:18~25:2~5.

[0010] Preferably, in the above-mentioned rammed earth paint, the mass ratio of the aluminum sulfate, sodium silicate and quaternary ammonium amphoteric polyacrylamide is 28:20:3.

[0011] Preferably, in the rammed earth paint, the cement is white cement. Furthermore, the color of the rammed earth layer can be adjusted by using different colored cements.

[0012] Preferably, in the above-mentioned rammed earth paint, the cellulose is hydroxypropyl methylcellulose.

[0013] Preferably, in the rammed earth paint, the length of the wood fiber is 100-500 μm. Further, the length of the wood fiber is 200-400 μm.

[0014] On the other hand, the present invention also provides a method for preparing the above-mentioned rammed earth paint, comprising the following steps:

[0015] (1) Mixing cellulose, side chain polyether modified amino silicone and water to obtain a mixed solution;

[0016] (2) mixing soil, cement, sand, wood fiber, water reducing agent, curing agent and starch phosphate to obtain a mixture;

[0017] (3) Add the mixed solution obtained in step (1) to the mixed material obtained in step (2) and stir to obtain rammed earth paint.

[0018] On the other hand, the present invention also provides the use of the rammed earth paint in building wall decoration.

[0019] Compared with the existing technology, the present invention has the following beneficial effects:

[0020] 1. The rammed earth paint of the present invention mainly uses soil, cement and sand as main materials, and is modified by adding side chain polyether modified amino silicone, starch phosphate and the like, which can improve the combination of soil and cement in the rammed earth paint, improve the uniformity and stability of the rammed earth paint, enhance the flexibility and strength of the rammed earth system, and avoid cracking, falling off and the like.

[0021] 2. The rammed earth paint of the present invention uses natural raw materials such as soil and sand as main materials, does not add toxic chemicals, and has good environmental protection. The rammed earth paint will not change the original color of the soil. The application of rammed earth paint in wall decoration can create the original color of the countryside. At the same time, the rammed earth layer obtained has good durability and crack resistance.

[0022] 3. The preparation method of the rammed earth paint of the present invention has a simple preparation process, does not require special processing equipment, is easy to operate, and has simple and convenient construction, high construction efficiency, short construction period, low comprehensive cost, and is economical and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a photo of the rammed earth layer made with the rammed earth paint of Example 1 of the present invention.

[0024] Figure 2 This is a photo of the rammed earth layer prepared by the rammed earth paint of Comparative Example 1 of the present invention.

[0025] Figure 3 This is a photo of the rammed earth layer prepared by the rammed earth paint of Comparative Example 2 of the present invention.

[0026] Figure 4 This is a photo of the rammed earth layer prepared by the rammed earth paint of Comparative Example 3 of the present invention.

[0027] Figure 5 This is a photo of the rammed earth layer prepared by the rammed earth paint of Comparative Example 4 of the present invention. Implementation

[0028] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited by the specific embodiments. If the specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially. "Parts by weight" refers to the basic measurement unit representing the weight ratio relationship of multiple components. 1 part can represent any unit mass. If the weight of component A is a part and the weight of component B is b parts, it represents the ratio of the mass of component A to the mass of component B, a:b. Alternatively, it represents that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, representing a multiple factor). Unlike mass percentage, the sum of the mass parts of all components is not limited to 100 parts. Soil material is natural soil obtained from nature. Example 1

[0029] A rammed earth paint is composed of the following raw materials in parts by weight: 25 parts of soil, 22 parts of cement, 45 parts of sand, 0.35 parts of hydroxypropyl methylcellulose, 0.4 parts of wood fiber, 0.25 parts of water reducer, 6.5 parts of side chain polyether modified amino silicone, 0.4 parts of curing agent, 0.8 parts of starch phosphate, and 22 parts of water. The curing agent is composed of aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide, and the mass ratio of aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide is 28:20:3. The soil is yellow mud, and the particle size of the yellow mud is less than 1 mm; the sand is calcium carbonate sand, and the particle size is 30-100 meshes. In the specific exterior wall decoration process, sand of different particle sizes can be selected according to the decoration effect. The cement is white silicate cement (425); the length of the wood fiber is 200-300 μm. The water reducer is sulfonated melamine water reducer BASF F10. The starch phosphate is single starch phosphate. The side chain polyether modified amino silicone was prepared by referring to the synthesis method of side chain polyether modified amino silicone in Huang Jie's paper "Synthesis, Characterization and Application Performance Research of Polyether Modified Silicone", and the quaternary ammonium amphoteric polyacrylamide was synthesized by referring to the method in Tang Li's paper "Synthesis and Application of Quaternary Ammonium Amphoteric Polyacrylamide".

[0030] The specific synthesis method of side chain polyether modified amino silicone is:

[0031] Take aminosilicone, polyoxyethylene polyoxypropylene glycidyl ether and isopropanol and add them into a three-necked flask with a thermometer, a stirrer and a reflux condenser. The mass ratio of aminosilicone to polyoxyethylene polyoxypropylene glycidyl ether is 2:1, and the isopropanol is 5 times the total mass of aminosilicone and polyoxyethylene polyoxypropylene glycidyl ether. Heat to 85°C and react for 5h. Then, evacuate the vacuum at a pressure of 55-80kPa to remove isopropanol. Finally, separate and purify by chromatography to obtain a bright yellow transparent viscous liquid, which is the side chain polyether modified amino silicone.

[0032] The preparation method of aminosilicon is as follows: octamethylcyclotetrasiloxane (D4) is added into a three-necked flask with a thermometer and a stirrer, heated to 100°C, KH-Si-121, KH-Si-602 and a catalyst (tetramethylammonium hydroxide) are added, the molar ratio of D4, KH-Si-121 and KH-Si-602 is 1:1:1, the amount of catalyst is 0.005% of the total amount of reactants, react for 2 hours, reduce pressure and remove low boiling points for 30 minutes at a vacuum degree of 55-80 kPa, then heat to 150°C to decompose the catalyst, reduce pressure and remove low boiling points for 30 minutes at a vacuum degree of 55-80 kPa, and obtain aminosilicon.

[0033] The preparation method of the rammed earth paint of this embodiment comprises the following steps:

[0034] (1) Mixing hydroxypropyl methylcellulose, side chain polyether modified amino silicone and water to obtain a mixed solution;

[0035] (2) mixing soil, cement, sand, wood fiber, water reducing agent, curing agent and starch phosphate to obtain a mixture;

[0036] (3) Add the mixed liquid obtained in step (1) to the dry mixed material obtained in step (2) and stir to mix well. The stirring rate is 50 r / min and the stirring time is 5 min to obtain rammed earth paint. Example 2

[0037] A rammed earth paint is composed of the following raw materials in parts by weight: 28 parts of soil, 24 parts of cement, 43 parts of sand, 0.32 parts of hydroxypropyl methylcellulose, 0.45 parts of wood fiber, 0.25 parts of water reducer, 5.5 parts of side chain polyether modified amino silicone, 0.4 parts of curing agent, 0.9 parts of starch phosphate, and 22 parts of water, wherein the curing agent is composed of aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide, and the mass ratio of aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide is 25:23:4. Other parts are the same as those in Example 1.

[0038] The preparation method of the rammed earth paint of this embodiment comprises the following steps:

[0039] (1) Mixing hydroxypropyl methylcellulose, side chain polyether modified amino silicone and water to obtain a mixed solution;

[0040] (2) mixing soil, cement, sand, wood fiber, water reducing agent, curing agent and starch phosphate to obtain a mixture;

[0041] (3) Add the mixed liquid obtained in step (1) to the dry mixed material obtained in step (2) and stir to mix well. The stirring rate is 50 r / min and the stirring time is 5 min to obtain rammed earth paint.

[0042] Comparative Example 1

[0043] The difference between this comparative example and Example 1 is that an equal amount of silane coupling agent A-187 is used to replace the side chain polyether modified amino silicone, and the rest is the same as Example 1.

[0044] Comparative Example 2

[0045] This comparative example is different from Example 1 in that starch is used to replace starch phosphate, and the rest is the same as Example 1.

[0046] Comparative Example 3

[0047] The difference between this comparative example and Example 1 is that cationic polyacrylamide (produced by Henan Zhongbei Fine Chemicals) is used to replace quaternary ammonium amphoteric polyacrylamide, and the rest is the same as Example 1.

[0048] Comparative Example 4

[0049] The rammed earth paint of this comparative example is composed of the following raw materials in parts by weight: 25 parts of soil, 22 parts of cement, 45 parts of sand, 0.35 parts of hydroxypropyl methylcellulose, 0.4 parts of wood fiber, 0.25 parts of water reducer, and 22 parts of water. The rest is the same as in Example 1.

[0050] Application Examples

[0051] The rammed earth paint is used for wall decoration. In the actual application process, a layer of about 0.5mm thick sealing primer layer (308 sealing primer) is first applied on the concrete wall, and then the rammed earth paint is scraped on the surface of the sealing primer and dried naturally. The rammed earth layer with a thickness of about 3mm is obtained by scraping the rammed earth paint of Example 1 and Comparative Examples 1 to 4. The photo of the rammed earth layer after drying for 24 hours is as follows: Figures 1 to 5 As shown in the figure, the rammed earth layer prepared by the rammed earth paint of Example 1 of the present invention has no cracks, the rammed earth layers prepared by the rammed earth paints of Comparative Examples 1 to 3 have no cracks after drying, and the rammed earth layer prepared by the rammed earth paint of Comparative Example 4 has many cracks and is obviously unusable.

[0052] The test results of the rammed earth paint of Example 1 and Comparative Examples 1 to 3, with reference to the test method in the standard GB / T 9779-2005 Multilayer architectural coatings, are shown in Table 1 for bonding strength, initial drying crack resistance, impact resistance, temperature change resistance, and water resistance. The two-layer structure (sealed primer + rammed earth) is shown in Table 1. Comparative Example 4 had cracks in the coating after drying, and the initial drying crack resistance test was performed, and no other performance tests were performed. As can be seen from Table 1, the bonding strength of the rammed earth paint of Example 1 is significantly better than that of Comparative Examples 1 to 3, and the impact resistance is higher than that of Comparative Example 1, indicating that the addition of side chain polyether modified amino silicone can improve the strength and toughness of rammed earth. Starch phosphate can not only prevent cracking, but also improve strength compared to starch.

[0053] Table 1 Performance data of rammed earth paint of Example 1 and Comparative Examples 1 to 3

[0054] Bond strength (MPa) Initial drying crack resistance Impact resistance Temperature resistance Water resistance 96h Example 1 1.55 No cracks The coating has no cracks, peeling or obvious deformation. After five times, the coating has no powdering, cracking, peeling, blistering, etc. No bubbling, shedding, etc. Example 2 1.52 No cracks The coating has no cracks, peeling or obvious deformation. After five times, the coating has no powdering, cracking, peeling, blistering, etc. No bubbling, shedding, etc. Comparative Example 1 1.37 No cracks The coating has a small amount of cracks, but no peeling or obvious deformation. After five times, the coating showed cracking, but no powdering, peeling, or blistering. No bubbling, shedding, etc. Comparative Example 2 1.41 No cracks The coating has no cracks, peeling or obvious deformation. After five times, the coating has no powdering, cracking, peeling, blistering, etc. No bubbling, shedding, etc. Comparative Example 3 1.46 No cracks The coating has no cracks, peeling or obvious deformation. After five times, the coating has no powdering, cracking, peeling, blistering, etc. No bubbling, shedding, etc. Comparative Example 4 — There are cracks — — —

[0055] In summary, the present invention can improve the flexibility and strength of the rammed earth system and avoid cracking, falling off and the like by optimizing the composition and proportion of the rammed earth paint.

[0056] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A rammed earth paint, characterized in that: The rammed earth paint comprises the following raw materials in parts by weight: 20 to 30 parts of soil, 20 to 30 parts of cement, 40 to 50 parts of sand, 0.3 to 0.4 parts of cellulose, 0.3 to 0.5 parts of wood fiber, 0.2 to 0.3 parts of water reducer, 5 to 8 parts of side chain polyether modified amino silicone, 0.3 to 0.5 parts of curing agent, 0.5 to 1 part of starch phosphate, and 18 to 30 parts of water; the curing agent is composed of aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide, and the mass ratio of the aluminum sulfate, sodium silicate, and quaternary ammonium amphoteric polyacrylamide is 20 to 30:18 to 25:2 to 5.

2. The rammed earth paint according to claim 1, characterized in that: The rammed earth paint comprises the following raw materials in parts by weight: 25 parts of soil, 22 parts of cement, 45 parts of sand, 0.35 parts of cellulose, 0.4 parts of wood fiber, 0.25 parts of water reducer, 6.5 parts of side chain polyether modified amino silicone, 0.4 parts of curing agent, 0.8 parts of starch phosphate, and 22 parts of water.

3. The rammed earth paint according to claim 1, characterized in that: The water reducing agent is a sulfonated melamine water reducing agent.

4. The rammed earth paint according to claim 1, characterized in that: The cement is white cement.

5. The rammed earth paint according to claim 1, characterized in that: The cellulose is hydroxypropyl methylcellulose.

6. The rammed earth paint according to claim 1, characterized in that: The length of the wood fiber is 100-500 μm.

7. A method for preparing rammed earth paint according to any one of claims 1 to 6, characterized in that: The following steps are involved: (1) stirring and mixing cellulose, side chain polyether modified amino silicone and water to obtain a mixed solution; (2) mixing soil, cement, sand, wood fiber, water reducing agent, curing agent, and starch phosphate to obtain a mixture; (3) Add the mixed solution obtained in step (1) to the mixed material obtained in step (2) and stir to obtain rammed earth paint.

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