Natural hydraulic lime-based outer wall spraying material and preparation method thereof

Abstract

The invention provides a natural hydraulic lime-based exterior wall spraying material and a preparation method thereof, and belongs to the technical field of building interior and exterior wall decoration. The formula comprises the natural hydraulic lime, the talcum powder, the white cement, the river sand, the water reducing agent, the bentonite, the water repellent, the polyvinyl alcohol, the defoaming agent and the titanium dioxide, the material can achieve high-quality exterior wall decoration through one-time construction, the construction process is greatly simplified, and the spraying material has the advantages of being environmentally friendly and capable of being widely applied to exterior wall decoration. Meanwhile, excellent crack resistance and self-healing characteristics are achieved, cracks can be effectively prevented from being generated in the face of temperature change, humidity fluctuation and external erosion, and the integrity of an outer wall structure is maintained.

Description

Technical Field

[0001] The invention relates to the technical field of building interior and exterior wall decoration, and in particular to a natural hydraulic lime-based exterior wall spraying material and a preparation method thereof. Background Art

[0002] At present, exterior wall decoration technology mainly relies on traditional methods such as cement-based plaster mortar, paint and exterior wall insulation system. These technologies have certain limitations in construction efficiency, durability, waterproof performance and environmental protection. The construction of cement-based mortar requires multiple layers of plastering and long-term drying. The process is complicated and time-consuming, and it is prone to cracks and peeling. Although the paint has the advantage of convenient construction, its weather resistance is relatively limited. It is easy to fade and peel off after long-term exposure to ultraviolet rays and rain. In addition, the paint often contains volatile organic compounds (VOC), which poses a potential threat to the environment and human health. Although the exterior wall insulation system can effectively provide insulation function, the construction process is relatively complicated, and the insulation materials are prone to aging and falling off with time and environmental changes. The root cause of these problems lies in the inherent limitations of traditional materials and the limitations of construction technology, which cannot fully meet the needs of modern buildings for high efficiency, durability and environmental protection performance. Summary of the invention

[0003] The purpose of the present invention is to provide a natural hydraulic lime-based exterior wall spraying material and a preparation method thereof, which are used to solve the technical problems of complicated exterior wall decoration construction, poor overall performance and environmental protection in the prior art.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The invention provides a natural hydraulic lime-based exterior wall spraying material, comprising the following components in parts by mass: 90-120 parts of natural hydraulic lime, 5-15 parts of talcum powder, 5-15 parts of white cement, 120-150 parts of river sand, 0.1-0.2 parts of water reducing agent, 1-3 parts of bentonite, 0.1-0.4 parts of water repellent, 2-4 parts of polyvinyl alcohol, 0.01-0.05 parts of defoaming agent, 1-5 parts of titanium dioxide and 40-45 parts of water.

[0006] Furthermore, the natural hydraulic lime is of NHL5 type.

[0007] Furthermore, the particle size of the talc powder is 350-450 mesh, and the strength grade of the white cement is 32.5, 42.5 or 52.5.

[0008] Furthermore, the particle size of the river sand is 100-200 meshes.

[0009] Further, the water reducing agent includes one or more of Melflux 2651F, Melment F10, Sika 540P, Sika 325c, and Walkley HK41274;

[0010] The water reducing rate of the water reducing agent is 23-28%.

[0011] Furthermore, the bentonite includes sodium bentonite, and the particle size of the bentonite is 300-350 meshes.

[0012] Further, the water repellent includes one or more of KR-750 silicone water repellent, SILRES BS POWDERA and SILRESBS POWDER D;

[0013] The polyvinyl alcohol includes one or more of PVA-2488, PVA-217 and PVA-BP17;

[0014] The defoaming agent includes one or more of P803, P800, P849, P841 and P8850;

[0015] The titanium dioxide includes rutile titanium dioxide.

[0016] The present invention also provides a method for preparing a natural hydraulic lime-based exterior wall spraying material, comprising mixing natural hydraulic lime, talcum powder, white cement, river sand, a water reducer, bentonite, a water repellent, polyvinyl alcohol and a defoamer according to weight fractions, then adding water and stirring, and adding titanium dioxide during the stirring process.

[0017] Furthermore, the stirring speed is 60-80 r / min, and the stirring time is 3-5 min.

[0018] Beneficial effects of the present invention:

[0019] The present invention realizes efficient and rapid construction through one-time spraying, reducing the construction period and cost pressure. The spraying material of the present invention has excellent crack resistance and self-healing properties, and can effectively prevent the generation of cracks and maintain the integrity of the exterior wall structure when facing temperature changes, humidity fluctuations and external erosion. Its waterproof and breathable performance ensures that external moisture cannot penetrate the wall, while allowing internal moisture to be discharged smoothly, avoiding damage to the wall in a humid environment, and further strengthening the protective effect of the building. In addition, the material does not contain volatile organic compounds (VOCs), and can also absorb carbon dioxide during the hardening process, which meets the requirements of contemporary architecture for environmental protection and low-carbon development. DETAILED DESCRIPTION

[0020] The invention provides a natural hydraulic lime-based exterior wall spraying material, comprising the following components in parts by mass: 90-120 parts of natural hydraulic lime, 5-15 parts of talcum powder, 5-15 parts of white cement, 120-150 parts of river sand, 0.1-0.2 parts of water reducing agent, 1-3 parts of bentonite, 0.1-0.4 parts of water repellent, 2-4 parts of polyvinyl alcohol, 0.01-0.05 parts of defoaming agent, 1-5 parts of titanium dioxide and 40-45 parts of water.

[0021] In the present invention, the amount of natural hydraulic lime added is preferably 95 to 110 parts by mass, and more preferably 100 parts by mass.

[0022] In the present invention, the amount of talc added is preferably 7 to 12 parts by mass, and more preferably 10 parts by mass.

[0023] In the present invention, the amount of white cement added is preferably 8 to 12 parts by mass, and more preferably 10 parts by mass.

[0024] In the present invention, the amount of river sand added is preferably 130 to 140 parts by mass, and more preferably 135 parts by mass.

[0025] In the present invention, the amount of the water reducing agent added is preferably 0.15 parts by mass.

[0026] In the present invention, the amount of bentonite added is preferably 2 parts by mass.

[0027] In the present invention, the amount of the water repellent added is preferably 0.2 to 0.3 parts by mass, and more preferably 0.25 parts by mass.

[0028] In the present invention, the amount of polyvinyl alcohol added is preferably 3 parts by mass.

[0029] In the present invention, the amount of the defoaming agent added is preferably 0.02 to 0.04 parts by mass, and more preferably 0.03 parts.

[0030] In the present invention, the addition amount of the titanium dioxide is preferably 2 to 4 parts by mass, and more preferably 3 parts by mass.

[0031] In the present invention, the amount of water added is preferably 43 parts by mass.

[0032] In the present invention, the natural hydraulic lime is preferably NHL5 type.

[0033] In the present invention, the particle size of the talc powder is 350-450 mesh, preferably 400 mesh, and the strength grade of the white cement is 32.5, 42.5 or 52.5, preferably 42.5.

[0034] In the present invention, the particle size of the river sand is 100-200 meshes, preferably 120-180 meshes, and more preferably 150 meshes.

[0035] In the present invention, the water reducer includes a polycarboxylate water reducer.

[0036] In the present invention, the water reducing agent includes one or more of Melflux 2651F, Melment F10, Sika 540P, Sika 325c, and Walkley HK41274; preferably one or more of Melflux 2651F, Melment F10, and Sika 540P, and more preferably Melflux 2651F;

[0037] The water reducing agent has a water reducing rate of 23 to 28%, preferably 25%.

[0038] In the present invention, the bentonite includes sodium bentonite, preferably sodium bentonite, and the particle size of the bentonite is 300-350 meshes, preferably 320 meshes.

[0039] In the present invention, the water repellent includes one or more of KR-750 silicone water repellent, SILRES BS POWDERA and SILRES BS POWDER D, preferably KR-750 silicone water repellent or SILRES BS POWDERA, and more preferably KR-750 silicone water repellent;

[0040] The polyvinyl alcohol includes one or more of PVA-2488, PVA-217 and PVA-BP17, preferably PVA-2488 polyvinyl alcohol;

[0041] The defoamer includes one or more of P803, P800, P849, P841 and P8850, preferably P803 defoamer;

[0042] The titanium dioxide includes rutile titanium dioxide, preferably rutile titanium dioxide.

[0043] The present invention also provides a method for preparing a natural hydraulic lime-based exterior wall spraying material, comprising mixing natural hydraulic lime, talcum powder, white cement, river sand, a water reducer, bentonite, a water repellent, polyvinyl alcohol and a defoamer according to weight fractions, then adding water and stirring, and adding titanium dioxide during the stirring process.

[0044] In the present invention, the titanium dioxide is used to adjust the whiteness, and the amount of titanium dioxide added needs to be determined according to the wall color requirements.

[0045] In the present invention, the stirring speed is 60-80 r / min, and the stirring time is 3-5 min.

[0046] In the present invention, the natural hydraulic lime-based exterior wall spraying material is sprayed using a mortar sprayer, and the spraying thickness is preferably 15 to 20 mm.

[0047] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0048] Example 1

[0049] In this embodiment, the water reducing agent is a polycarboxylic acid water reducing agent, the water repellent is a KR-750 type silicone water repellent, the polyvinyl alcohol is a PVA-2488 type, the defoaming agent is a P803 type defoaming agent, and the titanium dioxide is a rutile type titanium dioxide.

[0050] Example 2

[0051] Different from Example 1, in this example, the water reducing agent is Melflux 2651F, the water repellent is SILRESBS POWDERA, the polyvinyl alcohol is PVA-217, and the defoaming agent is P800.

[0052] Example 3

[0053] Different from Example 1, in this example, the water reducing agent is Melment F10, the water repellent is SILRES BSPOWDER D, the polyvinyl alcohol is PVA-BP17, and the defoaming agent is P800.

[0054] Embodiments 4 to 6

[0055] Different from Example 1, in Examples 4 to 6, the mass fractions of the raw materials are different.

[0056] Table 1 shows the formula of the natural hydraulic lime-based exterior wall spraying material of Examples 1 to 6 in parts by weight. The natural hydraulic lime-based exterior wall spraying material is obtained by stirring the mixture at a speed of 70 r / min for 5 minutes according to the formula shown in Table 1.

[0057] Table 1 Formula of natural hydraulic lime-based exterior wall spraying material of Examples 1 to 6

[0058]

[0059] The natural hydraulic lime-based exterior wall spraying materials prepared in Examples 1 to 6 were tested for compressive strength, fluidity, flexural strength, tensile bond strength, water absorption, and drying shrinkage. The test methods are as follows:

[0060] Refer to EN 459-2-2021 "Building Lime-Part 2: Test Methods" to test compressive strength and fluidity; refer to JC / T 1024-2007 "Wall Finishing Mortar" to test flexural strength; refer to JGJ / T70-2009 "Standard for Test Methods for Basic Properties of Building Mortar" to test tensile bond strength, water absorption and drying shrinkage.

[0061] Table 2 shows the test results of various properties of the spraying materials prepared in Examples 1 to 6.

[0062] Table 2 Performance test results of the spraying materials prepared in Examples 1 to 6

[0063]

[0064] As can be seen from the above embodiments, the present invention provides a natural hydraulic lime-based exterior wall spray material and a preparation method thereof. As can be seen from Table 2, the spray material of the present invention has excellent crack resistance and self-healing properties, and can effectively prevent the generation of cracks and maintain the integrity of the exterior wall structure when facing temperature changes, humidity fluctuations and external erosion. Its waterproof and breathable properties ensure that external moisture cannot penetrate the wall, while allowing internal moisture to be discharged smoothly, avoiding damage to the wall in a humid environment, and further enhancing the protective effect of the building. Therefore, the present invention solves the technical problems of complicated exterior wall decoration construction, poor overall performance and environmental protection in the prior art.

[0065] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A natural hydraulic lime-based exterior wall spraying material, characterized in that: The invention comprises the following components in parts by weight: 90-120 parts of natural hydraulic lime, 5-15 parts of talc, 5-15 parts of white cement, 120-150 parts of river sand, 0.1-0.2 parts of water reducing agent, 1-3 parts of bentonite, 0.1-0.4 parts of water repellent, 2-4 parts of polyvinyl alcohol, 0.01-0.05 parts of defoaming agent, 1-5 parts of titanium dioxide and 40-45 parts of water.

2. A natural hydraulic lime-based exterior wall spraying material according to claim 1, characterized in that: The natural hydraulic lime is of NHL5 type.

3. A natural hydraulic lime-based exterior wall spraying material according to claim 1 or 2, characterized in that: The particle size of the talc powder is 350-450 meshes, and the strength grade of the white cement is 32.5, 42.5 or 52.

5.

4. A natural hydraulic lime-based exterior wall spraying material according to claim 3, characterized in that: The particle size of the river sand is 100-200 meshes.

5. A natural hydraulic lime-based exterior wall spraying material according to claim 1, 2 or 4, characterized in that: The water reducing agent includes one or more of Melflux 2651F, Melment F10, Sika 540P, Sika 325c, and Walkley HK41274; The water reducing rate of the water reducing agent is 23-28%.

6. A natural hydraulic lime-based exterior wall spraying material according to claim 5, characterized in that: The bentonite includes sodium-based bentonite, and the particle size of the bentonite is 300-350 meshes.

7. A natural hydraulic lime-based exterior wall spraying material according to claim 1, 2, 4 or 6, characterized in that: The water repellent includes KR-750 type silicone water repellent 、 One or more of SILRES BS POWDER A and SILRES BS POWDER D; The polyvinyl alcohol includes one or more of PVA-2488, PVA-217 and PVA-BP17; The defoaming agent includes one or more of P803, P800, P849, P841 and P8850; The titanium dioxide includes rutile titanium dioxide.

8. The method for preparing the natural hydraulic lime-based exterior wall spraying material according to any one of claims 1 to 7, characterized in that: Natural hydraulic lime, talcum powder, white cement, river sand, water reducing agent, bentonite, water repellent, polyvinyl alcohol and defoaming agent are mixed according to the mass proportions, then water is added and stirred, and titanium dioxide is added during the stirring process.

9. The method for preparing a natural hydraulic lime-based exterior wall spraying material according to claim 8, characterized in that: The stirring speed is 60-80 r / min, and the stirring time is 3-5 min.

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