A plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar and its preparation method

Abstract

This invention provides a plant fiber-modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar and its preparation method, belonging to the field of building materials technology. The plastering mortar of this invention comprises the following components: 40-60 parts of natural hydraulic lime; 40-120 parts of fine aggregate; 10-25 parts of silica fume; 2-10 parts of plant fiber; 20-40 parts of water; 0.2-3 parts of water-reducing agent; 0.2-2 parts of water-retaining agent; and 0.2-1 parts of waterproofing agent. The natural breathability of the hydraulic lime and plant fiber in this invention can regulate indoor humidity and prevent mold growth. The porous structure of the plant fiber gives the material good thermal insulation properties, making it suitable for use in building insulation layers.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to a plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar and its preparation method. Background Technology

[0002] With the promotion of green building concepts and the increasing awareness of sustainable development, the application of eco-friendly materials in the construction field has received increasing attention. Traditional building materials, such as cement and concrete, while possessing excellent mechanical properties, consume large amounts of energy during their production and are accompanied by significant carbon emissions, which does not align with the direction of modern green building development. Natural hydraulic lime (NHL), as a traditional building material, demonstrates great potential in sustainable development and green building. It not only possesses good air permeability and environmental friendliness but also solidifies by absorbing carbon dioxide from the air, thus exhibiting a certain carbon sequestration effect. Natural hydraulic lime has wide applications in the restoration of ancient buildings, ecological architecture, and other scenarios requiring air permeability and moisture regulation.

[0003] However, despite the many advantages of natural hydraulic lime, its physical and mechanical properties (such as compressive strength and tensile strength) are still inferior to those of modern cement-based materials, especially in terms of crack resistance, tensile strength, and toughness. Therefore, how to modify natural hydraulic lime mortar to improve its mechanical properties and durability while maintaining its original advantages has become one of the key research focuses.

[0004] Against this backdrop, the introduction of plant fibers offers a new approach to modifying natural hydraulic lime mortar. Plant fibers are widely available, inexpensive, and possess advantages such as high strength, lightweight, and renewability. By incorporating plant fibers into natural hydraulic lime mortar, not only can the tensile and crack resistance of the mortar be enhanced, but the thermal and sound insulation properties of the material can also be improved, thereby further broadening its application areas. Therefore, researching the preparation process and properties of plant fiber-modified natural hydraulic lime mortar is of great significance for promoting the development of green building materials. Summary of the Invention

[0005] The purpose of this invention is to provide a plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar and its preparation method, so as to solve the technical problems of insufficient mechanical properties and durability of existing natural hydraulic lime.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar, composed of the following components in parts by weight: 40-60 parts of natural hydraulic lime; 40-120 parts fine aggregate; 10-25 parts silica fume; 2-10 parts plant fiber; 20-40 parts water; Water-reducing agent 0.2~3 parts; Water-retaining agent 0.2~2 parts; Waterproofing agent 0.2~1 part; The plant fiber is obtained through alkali washing treatment.

[0007] Furthermore, the alkaline washing is performed by immersing the plant fibers in a sodium hydroxide solution with a volume fraction of 2-5%, then removing and air-drying them.

[0008] Furthermore, the natural hydraulic lime is NHL3.5 hydraulic lime or NHL5 hydraulic lime.

[0009] Furthermore, the plant fiber is one or more of jute fiber, flax fiber, straw fiber, coconut shell fiber, wood fiber, and bamboo fiber.

[0010] Furthermore, the fine aggregate is fine sand with a particle size of 0.1~0.3mm.

[0011] Furthermore, the water-reducing agent is a polycarboxylate water-reducing agent and / or a naphthalene-based water-reducing agent.

[0012] Furthermore, the water-retaining agent is one or more of hydroxypropyl methylcellulose, carboxymethyl cellulose, methylcellulose, ethyl cellulose, polyvinyl alcohol, and polyacrylamide.

[0013] Furthermore, the waterproofing agent is one or more of silane waterproofing agents, siloxane waterproofing agents, and organosilicon resin waterproofing agents.

[0014] This invention also provides a method for preparing plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar, comprising the following steps: 1) Mix natural hydraulic lime, fine aggregate, silica fume and plant fiber to obtain mixture 1; 2) Add the water-reducing agent, water-retaining agent, waterproofing agent and water to mixture 1 in sequence, and mix thoroughly.

[0015] The beneficial effects of this invention are: (1) Fibers can be dispersed in the lime matrix, absorb stress, and significantly enhance the tensile and flexural strength of the material. (2) The porous structure of plant fibers gives the material good thermal insulation properties, making it suitable for use in building insulation layers. (3) The natural breathability of hydraulic lime and plant fibers can regulate indoor humidity and prevent mold growth. (4) Both natural hydraulic lime and plant fibers are renewable or natural materials, which are environmentally friendly and sustainable, meeting the requirements of green building. Detailed Implementation

[0016] This invention provides a plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar, composed of the following components in parts by weight: 40-60 parts of natural hydraulic lime; 40-120 parts fine aggregate; 10-25 parts silica fume; 2-10 parts plant fiber; 20-40 parts water; Water-reducing agent 0.2~3 parts; Water-retaining agent 0.2~2 parts; Waterproofing agent 0.2~1 part; The plant fiber is obtained through alkali washing treatment.

[0017] In this invention, the content of the natural hydraulic lime is preferably 45-55 parts by weight, and more preferably 48-52 parts by weight.

[0018] In this invention, the content of fine aggregate is preferably 50-110 parts by weight, and more preferably 60-100 parts by weight.

[0019] In this invention, the content of silica fume is preferably 15 to 20 parts by weight, and more preferably 16 to 18 parts by weight.

[0020] In this invention, the content of plant fiber is preferably 3 to 9 parts by weight, and more preferably 4 to 8 parts by weight.

[0021] In this invention, the water content is preferably 25 to 35 parts by mass, and more preferably 30 to 32 parts by mass.

[0022] In this invention, the content of the water-reducing agent is preferably 0.5 to 2.5 parts by weight, and more preferably 1 to 2 parts by weight.

[0023] In this invention, the content of the water-retaining agent is preferably 0.5 to 1.5 parts by weight, and more preferably 0.8 to 1.2 parts by weight.

[0024] In this invention, the content of the waterproofing agent is preferably 0.5 to 0.8 parts by weight, and more preferably 0.6 to 0.7 parts by weight.

[0025] In this invention, the alkaline washing is performed by immersing the plant fibers in a sodium hydroxide solution with a volume fraction of 2-5%, then removing and air-drying them. Preferably, a sodium hydroxide solution with a volume fraction of 3-4% is used.

[0026] In this invention, the pretreatment process for plant fibers is as follows: S1: Cut long fibers into 3~10mm lengths to facilitate uniform dispersion in lime slurry; S2: Soak the fibers in deionized water for 2-4 hours to remove impurities and grease from the fiber surface and ensure that the fiber surface is clean; S3: Soak plant fibers in a 2%-5% sodium hydroxide solution for 1-2 hours to remove some lignin and hemicellulose, increase fiber surface roughness, and improve interfacial adhesion with lime.

[0027] In this invention, the soaking time is 1 to 3 hours, preferably 1.5 to 3 hours.

[0028] In this invention, the natural hydraulic lime is NHL3.5 hydraulic lime or NHL5 hydraulic lime, preferably NHL3.5 hydraulic lime.

[0029] In this invention, the plant fiber is one or more of jute fiber, flax fiber, straw fiber, coconut shell fiber, wood fiber and bamboo fiber, preferably one or more of jute fiber, flax fiber and straw fiber.

[0030] In this invention, the fine aggregate is fine sand with a particle size of 0.1~0.3mm, preferably fine sand with a particle size of 0.2~0.3mm.

[0031] In this invention, the water-reducing agent is a polycarboxylate water-reducing agent and / or a naphthalene-based water-reducing agent, preferably a polycarboxylate water-reducing agent.

[0032] In this invention, the water-retaining agent is one or more of hydroxypropyl methylcellulose, carboxymethylcellulose, methylcellulose, ethylcellulose, polyvinyl alcohol, and polyacrylamide, preferably one or more of hydroxypropyl methylcellulose, carboxymethylcellulose, and methylcellulose.

[0033] In this invention, the waterproofing agent is one or more of silane waterproofing agents, siloxane waterproofing agents, and organosilicon resin waterproofing agents, preferably silane waterproofing agents.

[0034] This invention also provides a method for preparing plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar, comprising the following steps: 1) Mix natural hydraulic lime, fine aggregate, silica fume and plant fiber to obtain mixture 1; 2) Add the water-reducing agent, water-retaining agent, waterproofing agent and water to mixture 1 in sequence, and mix thoroughly.

[0035] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0036] Example 1

[0037] A pretreatment method for jute fiber: S1: Cut jute fibers into 3 mm short fibers to facilitate uniform dispersion in lime slurry.

[0038] S2: Soak it in deionized water for 2.5 hours to remove impurities and grease from the surface of jute fibers and ensure that the fiber surface is clean.

[0039] S3: Soak jute fibers in a 3% sodium hydroxide solution for 1.5 hours to remove some of the lignin and hemicellulose from the jute fibers, increase the surface roughness of the fibers, and improve the interfacial adhesion with lime.

[0040] A method for preparing jute fiber modified natural hydraulic lime mortar, by mass parts: NHL3.5 natural hydraulic lime: 40 parts; Fine aggregate: 50 parts; Silica fume: 10 parts; Jute fiber: 5 parts; Water: 25 parts; Naphthalene-based water-reducing agent: 1 part; Hydroxymethyl cellulose: 0.5 parts; Silane waterproofing agent: 0.3 parts; S1: Mix 40 parts of natural hydraulic lime, 50 parts of fine aggregate, 10 parts of silica fume and 5 parts of jute fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0041] S2: Gradually add 1 part naphthalene-based water-reducing agent, 0.5 parts hydroxymethyl cellulose, 0.3 parts silane waterproofing agent, and 25 parts water, while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0042] Example 2

[0043] A pretreatment method for jute fiber: S1: Cut jute fibers into 3 mm short fibers to facilitate uniform dispersion in lime slurry.

[0044] S2: Soak it in deionized water for 2.5 hours to remove impurities and grease from the surface of jute fibers and ensure that the fiber surface is clean.

[0045] S3: Soak jute fibers in a 3% sodium hydroxide solution for 1.5 hours to remove some of the lignin and hemicellulose from the jute fibers, increase the surface roughness of the fibers, and improve the interfacial adhesion with lime.

[0046] A method for preparing jute fiber modified natural hydraulic lime mortar, by mass parts: NHL5 natural hydraulic lime: 50 parts; Fine aggregate: 100 parts; Silica fume: 20 parts; Jute fiber: 8 parts; Water: 35 parts; Naphthalene-based water-reducing agent: 2 parts; Hydroxymethyl cellulose: 1 part; Silane waterproofing agent: 0.5 parts; S1: Mix 50 parts of natural hydraulic lime, 100 parts of fine aggregate, 20 parts of silica fume and 8 parts of jute fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0047] S2: Gradually add 2 parts naphthalene-based water-reducing agent, 1 part hydroxymethyl cellulose, 0.5 parts silane waterproofing agent, and 35 parts water, while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0048] Example 3

[0049] A method for pretreating flax fibers: S1: Cut the flax fibers into 4 mm pieces to facilitate even dispersion in the lime slurry.

[0050] S2: Soak flax fibers in deionized water for 2.5 hours to remove impurities and grease from the fiber surface and ensure the fiber surface is clean.

[0051] S3: Soak flax fibers in 4% sodium hydroxide for 1.5 hours to remove some lignin and hemicellulose, increase fiber surface roughness, and improve interfacial adhesion with lime.

[0052] A method for preparing flax fiber modified natural hydraulic lime mortar, by mass parts: NHL5 natural hydraulic lime: 50 parts; Fine aggregate: 100 parts; Silica fume: 20 parts; Flax fiber: 8 parts; Water: 35 parts; Water-reducing agent: 2 parts; Water-retaining agent: 1.5 parts; Waterproofing agent: 1 part; S1: Mix 50 parts of natural hydraulic lime, 100 parts of fine aggregate, 20 parts of silica fume and 8 parts of flax fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0053] S2: Gradually add 2 parts naphthalene-based water-reducing agent, 1.5 parts hydroxymethyl cellulose, 1 part silane waterproofing agent, and 35 parts water, while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0054] Example 4

[0055] A method for pretreating flax fibers: S1: Cut the flax fibers into 4 mm pieces to facilitate even dispersion in the lime slurry.

[0056] S2: Soak flax fibers in deionized water for 2.5 hours to remove impurities and grease from the fiber surface and ensure the fiber surface is clean.

[0057] S3: Soak flax fibers in 4% sodium hydroxide for 1.5 hours to remove some lignin and hemicellulose, increase fiber surface roughness, and improve interfacial adhesion with lime.

[0058] A second aspect of the present invention provides a method for preparing flax fiber modified natural hydraulic lime mortar, wherein, by mass parts: NHL3.5 natural hydraulic lime: 40 parts; Fine aggregate: 80 parts; Silica fume: 10 parts; Flax fiber: 10 parts; Water: 25 parts; Water-reducing agent: 1 part; Water-retaining agent: 0.5 parts; Waterproofing agent: 0.3 parts; S1: Mix 40 parts of natural hydraulic lime, 80 parts of fine aggregate, 10 parts of silica fume and 10 parts of flax fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0059] S2: Gradually add 2 parts naphthalene-based water-reducing agent, 1 part hydroxymethyl cellulose, 0.5 parts silane waterproofing agent, and 35 parts water, while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0060] In this embodiment, the mortar fluidity reaches 195 mm, the setting time is 570 min, the 28-day compressive strength reaches 6.5 MPa, the 28-day flexural strength reaches 3 MPa, the 28-day bond strength reaches 1 MPa, and the 28-day shrinkage rate is 0.13%.

[0061] Example 5

[0062] A pretreatment method for jute fiber: S1: Cut jute fibers into 3 mm short fibers to facilitate uniform dispersion in lime slurry.

[0063] S2: Soak it in deionized water for 2.5 hours to remove impurities and grease from the surface of jute fibers and ensure that the fiber surface is clean.

[0064] S3: Soak jute fibers in a 3% sodium hydroxide solution for 1.5 hours to remove some of the lignin and hemicellulose from the jute fibers, increase the surface roughness of the fibers, and improve the interfacial adhesion with lime.

[0065] A method for preparing jute fiber modified natural hydraulic lime mortar, by mass parts: NHL5 natural hydraulic lime: 50 parts; Fine aggregate: 100 parts; Silica fume: 20 parts; Jute fiber: 8 parts; Water: 35 parts; Naphthalene-based water-reducing agent: 2 parts; Hydroxymethyl cellulose: 1 part; Silane waterproofing agent: 0.5 parts; S1: Mix 50 parts of natural hydraulic lime, 100 parts of fine aggregate, 20 parts of silica fume and 8 parts of jute fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0066] S2: Gradually add 2 parts naphthalene-based water-reducing agent, 1 part hydroxymethyl cellulose, 0.5 parts silane waterproofing agent, and 35 parts water, while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0067] Example 6

[0068] A pretreatment method for bamboo fiber: S1: Cut bamboo fibers to 5 mm to facilitate even dispersion in lime slurry.

[0069] S2: Soak bamboo fiber in deionized water for 2 hours to remove impurities and grease from the fiber surface and ensure the fiber surface is clean.

[0070] S3: Soak bamboo fiber in 3% sodium hydroxide solution for 1.5 hours to remove some lignin and hemicellulose, increase fiber surface roughness, and improve interfacial adhesion with lime.

[0071] A method for preparing plant fiber modified natural hydraulic lime mortar, by mass parts: NHL5 natural hydraulic lime: 50 parts; Fine aggregate: 100 parts; Silica fume: 20 parts; Bamboo fiber: 10 parts; Water: 35 parts; Water-reducing agent: 2 parts; Water-retaining agent: 1 part; Waterproofing agent: 0.5 parts; S1: Mix 50 parts of natural hydraulic lime, 100 parts of fine aggregate, 20 parts of silica fume and 10 parts of bamboo fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0072] S2: Gradually add 2 parts naphthalene-based water-reducing agent, 1 part hydroxymethyl cellulose, 0.5 parts silane waterproofing agent, and 25 parts water, while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0073] Example 7

[0074] A pretreatment method for rice straw fibers: S1: Cut the straw fibers into 4 mm pieces to facilitate even dispersion in the lime slurry.

[0075] S2: Soak the straw fiber in deionized water for 2.5 hours to remove impurities and grease from the fiber surface and ensure that the fiber surface is clean.

[0076] S3: Soak rice straw fibers in 4% sodium hydroxide for 1.5 hours to remove some lignin and hemicellulose, increase fiber surface roughness, and improve interfacial adhesion with lime.

[0077] A method for preparing flax fiber modified natural hydraulic lime mortar, by mass parts: NHL3.5 natural hydraulic lime: 50 parts; Fine aggregate: 100 parts; Silica fume: 20 parts; Rice straw fiber: 10 parts; Water: 35 parts; Water-reducing agent: 2 parts; Water-retaining agent: 1 part; Waterproofing agent: 1 part; S1: Mix natural hydraulic lime, fine aggregate and plant fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0078] S2: Gradually add plasticizer, water-retaining agent, waterproofing agent, and water while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0079] In this embodiment, the mortar fluidity reaches 195 mm, the setting time is 570 min, the 28-day compressive strength reaches 6.5 MPa, the 28-day flexural strength reaches 3 MPa, the 28-day bond strength reaches 1 MPa, and the 28-day shrinkage rate is 0.13%.

[0080] Example 8

[0081] A pretreatment method for rice straw fibers: S1: Cut the straw fibers into 8 mm pieces to facilitate even dispersion in the lime slurry.

[0082] S2: Soak the straw fiber in deionized water for 2.5 hours to remove impurities and grease from the fiber surface and ensure that the fiber surface is clean.

[0083] S3: Soak rice straw fibers in 4% sodium hydroxide for 1.5 hours to remove some lignin and hemicellulose, increase fiber surface roughness, and improve interfacial adhesion with lime.

[0084] A method for preparing plant fiber modified natural hydraulic lime mortar, by mass parts: NHL5 natural hydraulic lime: 50 parts; Fine aggregate: 100 parts; Silica fume: 20 parts; Rice straw fiber: 5 parts; Water: 35 parts; Water-reducing agent: 2 parts; Water-retaining agent: 1 part; Waterproofing agent: 1 part; S1: Mix natural hydraulic lime, fine aggregate and plant fiber evenly in a dry state for 10 minutes to ensure that the fiber and lime are evenly distributed.

[0085] S2: Gradually add plasticizer, water-retaining agent, waterproofing agent, and water while stirring the mixture to ensure a uniform lime slurry is formed. Stir for 10 minutes to ensure thorough mixing of the fiber and the slurry.

[0086] Comparative Example 1: NHL3.5 natural hydraulic lime mortar.

[0087] Comparative Example 2: NHL5 natural hydraulic lime mortar.

[0088] The mortar in the example was tested using the following method: The method for determining the fluidity of cement mortar is based on GB / T 2419—2005 "Method for Determination of Flowability of Cement Mortar"; The method for determining setting time is based on Part VIII of JGJ / T 70-2009 "Test Methods for Basic Properties of Building Mortar"; The method for determining compressive / flexural strength is based on Part 9 of JGJ / T 70-2009 "Test Methods for Basic Properties of Building Mortar"; The method for determining bond strength is based on Part 10 of JGJ / T 70-2009 "Test Methods for Basic Properties of Building Mortar"; The method for determining the drying shrinkage rate is based on Part XII of JGJ / T 70-2009 "Test Methods for Basic Properties of Building Mortar"; The contact angle test method is based on ASTM D7334-08, "Standard Practice for Evaluating Surface Wettability by Contact Angle Measurement", and the test results are shown in Table 1 below.

[0089] Table 1

[0090] As shown in Table 1, the plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar, while maintaining similar construction fluidity and setting time, achieved a leapfrog performance upgrade compared to the comparative example: the comparative example had extremely low flexural strength (only 0.1-0.2 MPa), huge shrinkage (up to 2.0%), and a hydrophilic surface (contact angle of about 53-62°), while the examples exhibited excellent toughness (flexural strength increased to 2.0-4.5 MPa), excellent micro-shrinkage characteristics (shrinkage rate generally controlled at 0.10-0.13%), and excellent superhydrophobic protective ability (contact angle generally greater than 125°), thus solving the fatal defects of high brittleness, easy cracking, and poor waterproof performance of the material.

[0091] As can be seen from the above embodiments, the present invention provides a plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar and its preparation method. The natural hydraulic lime and plant fiber of the present invention are both renewable or natural materials, environmentally friendly and sustainable, meeting the requirements of green building.

[0092] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar, characterized in that, It consists of components comprising the following parts by mass: 40-60 parts of natural hydraulic lime; 40-120 parts fine aggregate; 10-25 parts silica fume; 2-10 parts plant fiber; 20-40 parts water; Water-reducing agent 0.2~3 parts; Water-retaining agent 0.2~2 parts; Waterproofing agent 0.2~1 part; The plant fiber is obtained through alkali washing treatment.

2. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 1, characterized in that, The alkaline washing process involves immersing the plant fibers in a 2-5% (v / v) sodium hydroxide solution, then removing and air-drying them.

3. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 1 or 2, characterized in that, The natural hydraulic lime is NHL3.5 hydraulic lime or NHL5 hydraulic lime.

4. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 3, characterized in that, The plant fiber is one or more of jute fiber, flax fiber, straw fiber, coconut fiber, wood fiber, and bamboo fiber.

5. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 1 or 4, characterized in that, The fine aggregate is fine sand with a particle size of 0.1~0.3mm.

6. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 5, characterized in that, The water-reducing agent is a polycarboxylate water-reducing agent and / or a naphthalene-based water-reducing agent.

7. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 6, characterized in that, The water-retaining agent is one or more of hydroxypropyl methylcellulose, carboxymethylcellulose, methylcellulose, ethylcellulose, polyvinyl alcohol, and polyacrylamide.

8. The plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to claim 7, characterized in that, The waterproofing agent is one or more of silane waterproofing agents, siloxane waterproofing agents, and organosilicon resin waterproofing agents.

9. The method for preparing plant fiber modified superhydrophobic self-cleaning natural hydraulic lime-based plastering mortar according to any one of claims 1 to 8, characterized in that, Includes the following steps: 1) Mix natural hydraulic lime, fine aggregate, silica fume and plant fiber to obtain mixture 1; 2) Add the water-reducing agent, water-retaining agent, waterproofing agent and water to mixture 1 in sequence, and mix thoroughly.

Images