Slag modified rubber cement mortar and preparation process thereof

Abstract

The invention discloses slag modified rubber cement mortar and a preparation process thereof, and relates to the technical field of cement mortar, the addition of rubber particles can improve the sound insulation performance of the cement mortar, but can lead to obvious reduction of the strength of the cement mortar. The polypropylene fiber has the advantages of high tensile strength, friction resistance and the like, so that the strength of the cement mortar can be improved and the durability of the cement mortar can be enhanced by adding the polypropylene fiber into the cement mortar. The rubber particles and the polypropylene fibers are compounded by using the dopamine, and the hydrophilicity of the rubber particle-polypropylene fiber compound is also improved by using the dopamine, so that the water glass solution is better loaded on the surface of the rubber particle-polypropylene fiber compound, and the mechanical property of the cement mortar is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of cement mortar, and specifically to a slag-modified rubber cement mortar and its preparation process. Background Technique

[0002] The main components of cement include slag, fly ash and silica fume, which have characteristics such as corrosion resistance and high pressure resistance, and are suitable for extreme environments such as deep-sea infrastructure.

[0003] As a common industrial waste residue, slag has potential utilization value. Applying it to cement mortar can not only reduce environmental pollution, but also improve the performance of the mortar. In the prior art, the dispersibility and interfacial bonding force of rubber particles in cement mortar still need to be further improved. In addition, how to give full play to the synergistic effect of slag and rubber and optimize the performance of cement mortar is also a problem to be solved.

[0004] In order to solve the above problems and improve the mechanical properties and sound insulation performance of cement mortar, the present invention provides a slag-modified rubber cement mortar and its preparation process. Summary of the Invention

[0005] The purpose of the present invention is to provide a slag-modified rubber cement mortar and its preparation process to solve the problems raised in the prior art.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A preparation process of a slag-modified rubber cement mortar includes the following steps:

[0008] Step 1: Mix portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material;

[0009] Step 2: Take manufactured sand, acrylic emulsion, modified rubber particle-polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture-retaining thickener, and stir evenly to obtain a slag-modified rubber cement mortar.

[0010] Preferably, the inorganic cementitious material includes the following components by weight: 70 - 75 parts of portland cement, 6 - 10 parts of kaolin, 3 - 5 parts of fly ash, and 3 - 6 parts of silica fume;

[0011] The slag-modified rubber cement mortar includes the following components by weight: take 45 - 50 parts of manufactured sand, 40 - 45 parts of acrylic emulsion, 45 - 52 parts of modified rubber particle-polypropylene fiber composite, 30 - 37 parts of inorganic cementitious material, 12 - 14 parts of slag, 15 - 18 parts of deionized water, 2 - 3 parts of redispersible latex powder, 2 - 3 parts of water reducer, and 0.5 - 1 part of moisture-retaining thickener.

[0012] More preferably, the preparation method of the modified rubber particle - polypropylene fiber composite is as follows: Dilute the sodium silicate solution with deionized water into a solution with the same mass as the rubber particle - polypropylene fiber composite; then spray the solution on the surface of the rubber particle - polypropylene fiber composite, dry it, and react under an ultraviolet lamp for 30 - 40 min to obtain the modified rubber particle - polypropylene fiber composite.

[0013] More preferably, the preparation method of the rubber particle - polypropylene fiber composite is as follows: Take rubber particles and deionized water, ultrasonically disperse for 1 - 2 h, add dopamine, stir for 20 - 40 min, add tris(hydroxymethyl)aminomethane buffer solution, add hydrochloric acid to adjust the pH value to 8.3 - 8.5, stir evenly, add pretreated polypropylene fibers and mercaptoacetic acid, stir for 22 - 24 h, centrifuge, wash, and dry to obtain the rubber particle - polypropylene fiber composite.

[0014] More preferably, the preparation method of the sodium silicate solution is as follows: Take sodium silicate water, phosphosilicate, vinyltrimethoxysilane, urea, hydroxypropyl methylcellulose, 2 - hydroxy - 2 - methyl - 1 - phenyl - 1 - propanone, and stir evenly to obtain the sodium silicate solution.

[0015] More preferably, the preparation method of the pretreated polypropylene fiber is as follows: Take polypropylene fibers, add them to a sodium hydroxide solution, soak for 3 - 5 h, take them out and wash to obtain the alkali - treated polypropylene fibers; then put the alkali - treated polypropylene fibers into styrene - acrylic emulsion and impregnate for 30 - 40 min, take them out and wash to obtain the pretreated polypropylene fibers.

[0016] More preferably, the water - reducing agent is a polycarboxylate water - reducing agent; the moisture - retaining thickener is hydroxypropyl methylcellulose ether.

[0017] More preferably, the particle size of the rubber particles is 10 - 20 mesh.

[0018] More preferably, the particle size of the polypropylene fibers is 3 - 50 mm.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The addition of rubber particles can improve the sound insulation performance of cement mortar, but will cause a significant decrease in the strength of cement mortar. Polypropylene fibers have the advantages of high tensile strength and wear resistance. Adding polypropylene fibers to cement mortar can improve the strength of cement mortar and enhance the durability of cement mortar at the same time.

[0021] The rubber particles are compounded with polypropylene fibers using dopamine. The use of dopamine also improves the hydrophilicity of the rubber particle - polypropylene fiber composite, enabling better loading of the sodium silicate solution on the surface of the rubber particle - polypropylene fiber composite, thereby enhancing the mechanical properties of the cement mortar.

[0022] 2. Spraying the sodium silicate solution on the surface of the rubber particle - polypropylene fiber composite. Relying on the gelling property and surface film - forming characteristics of sodium silicate, through the photoinitiator 2 - hydroxy - 2 - methyl - 1 - phenyl - 1 - propanone, a thiol - vinyl click reaction occurs to improve the interfacial bonding of the rubber particle - polypropylene fiber composite. The binding ability between the rubber particle - polypropylene fiber composite and the sodium silicate solution is enhanced, thereby enhancing the mechanical properties of the cement mortar.

[0023] 3. The modified rubber particle - polypropylene fiber composite has good hydrophilicity, enhancing its compatibility with the cement paste, thereby enhancing the mechanical properties of the cement mortar. Specific embodiments

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] There are no special restrictions on the sources and models of the substances involved in the present invention. Exemplarily, they include: the average particle size of the redispersible latex powder is 80μm, and the bulk density is 400 ± 100 g / L; rubber particles: particle size: 10 - 20 mesh, which can be purchased from the rubber particles produced by Huayi Rubber Co., Ltd.; redispersible latex powder: which can be purchased from Jusheng, with an average particle size of 80μm; Portland cement: product number: PO 52.5, which can be purchased from Qufu Zhonglian Cement Factory; polycarboxylate superplasticizer: model: SPC - 100; sodium silicate solution: which can be purchased from Wuhan Jiyesheng Chemical Co., Ltd.; polypropylene fibers: 3 - 50mm, which can be purchased from Shandong Xingmao Engineering Materials Co., Ltd.; styrene - acrylic emulsion: model: Y17677, which can be purchased from Shanghai Yuanye Biotechnology Co., Ltd.

[0026] Example 1: A preparation process for slag - modified rubber cement mortar, comprising the following steps:

[0027] Step 1: Preparation of slag - modified rubber cement mortar:

[0028] Mix the Portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material;

[0029] The inorganic cementitious material includes the following components by weight: 72 parts of portland cement, 8 parts of kaolin, 4 parts of fly ash, and 5 parts of silica fume;

[0030] Take machine-made sand, acrylic emulsion, modified rubber particle-polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture-retaining thickener, and stir evenly to obtain slag-modified rubber cement mortar;

[0031] The slag-modified rubber cement mortar includes the following components by weight: take 47 parts of machine-made sand, 42 parts of acrylic emulsion, 47 parts of modified rubber particle-polypropylene fiber composite, 35 parts of inorganic cementitious material, 13 parts of slag, 16 parts of deionized water, 2.5 parts of redispersible latex powder, 2.5 parts of water reducer, and 0.8 part of moisture-retaining thickener;

[0032] Step two: Preparation of rubber particle-polypropylene fiber composite:

[0033] Take polypropylene fiber, add it to a sodium hydroxide solution with a mass fraction of 4%, soak for 4 h, take out and wash to obtain alkali-treated polypropylene fiber; then immerse the alkali-treated polypropylene fiber in styrene-acrylic emulsion for 35 min, and the mass ratio of the alkali-treated polypropylene fiber to the styrene-acrylic emulsion is 1:2; take out and wash to obtain pretreated polypropylene fiber;

[0034] Take 30 g of rubber particles and 1000 mL of deionized water, ultrasonically disperse for 1.5 h, add 1 g of dopamine, stir for 30 min, add 1.2 g of tris(hydroxymethyl)aminomethane buffer solution, adjust the pH value to 8.4 with hydrochloric acid, stir evenly, add 7 g of pretreated polypropylene fiber and 10 g of mercaptoacetic acid, stir for 23 h, centrifuge, wash, and dry to obtain rubber particle-polypropylene fiber composite;

[0035] Step three: Preparation of sodium silicate solution:

[0036] Take 100 g of sodium silicate solution, 3.5 g of phosphosilicate, 5 g of vinyltrimethoxysilane, 1 g of urea, 1 g of hydroxypropyl methylcellulose, and 2 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone, and stir evenly to obtain sodium silicate solution;

[0037] Step four: Preparation of modified rubber particle-polypropylene fiber composite:

[0038] Dilute the sodium silicate solution with deionized water to a solution with the same mass as the rubber particle-polypropylene fiber composite; then evenly spray the solution on the surface of the rubber particle-polypropylene fiber composite through a sprayer, dry, and react under an 800 W ultraviolet lamp for 35 min to obtain the modified rubber particle-polypropylene fiber composite.

[0039] Example 2: A preparation process of slag-modified rubber cement mortar, comprising the following steps:

[0040] Step 1: Preparation of slag-modified rubber cement mortar:

[0041] Mix portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material;

[0042] The inorganic cementitious material comprises the following components by weight: 70 parts of portland cement, 6 parts of kaolin, 3 parts of fly ash, and 3 parts of silica fume;

[0043] Take manufactured sand, acrylic emulsion, modified rubber particle-polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture-retaining thickener, and stir evenly to obtain slag-modified rubber cement mortar;

[0044] The slag-modified rubber cement mortar comprises the following components by weight: take 45 parts of manufactured sand, 40 parts of acrylic emulsion, 45 parts of modified rubber particle-polypropylene fiber composite, 30 parts of inorganic cementitious material, 12 parts of slag, 15 parts of deionized water, 2 parts of redispersible latex powder, 2 parts of water reducer, and 0.5 part of moisture-retaining thickener;

[0045] Step 2: Preparation of rubber particle-polypropylene fiber composite:

[0046] Take polypropylene fiber, add it to a sodium hydroxide solution with a mass fraction of 4%, soak for 3 h, take out and wash to obtain alkali-treated polypropylene fiber; then immerse the alkali-treated polypropylene fiber in styrene-acrylic emulsion for 30 min, and the mass ratio of the alkali-treated polypropylene fiber to the styrene-acrylic emulsion is 1:2; take out and wash to obtain pretreated polypropylene fiber;

[0047] Take 30 g of rubber particles, 1000 mL of deionized water, ultrasonically disperse for 1 h, add 1 g of dopamine, stir for 20 min, add 1.2 g of tris(hydroxymethyl)aminomethane buffer solution, adjust the pH value to 8.3 with hydrochloric acid, stir evenly, add 7 g of pretreated polypropylene fiber, and 10 g of mercaptoacetic acid, stir for 22 h, centrifuge, wash, and dry to obtain a rubber particle-polypropylene fiber composite;

[0048] Step 3: Preparation of sodium silicate solution:

[0049] Take 100 g of sodium silicate solution, 3.5 g of silicon phosphate, 5 g of vinyltrimethoxysilane, 1 g of urea, 1 g of hydroxypropyl methylcellulose, and 2 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone, and stir evenly to obtain a sodium silicate solution;

[0050] Step 4: Preparation of modified rubber particle-polypropylene fiber composite:

[0051] The sodium silicate solution is diluted with deionized water into a solution with the same mass as the rubber particle - polypropylene fiber composite; then the solution is evenly sprayed on the surface of the rubber particle - polypropylene fiber composite through a sprayer, dried, and reacted under an 800W ultraviolet lamp for 30 min to obtain the modified rubber particle - polypropylene fiber composite.

[0052] Example 3: A preparation process of slag - modified rubber cement mortar, comprising the following steps:

[0053] Step 1: Preparation of slag - modified rubber cement mortar:

[0054] Portland cement, kaolin, fly ash, and silica fume are mixed evenly to obtain an inorganic cementitious material;

[0055] The inorganic cementitious material comprises the following components by weight: 75 parts of Portland cement, 10 parts of kaolin, 5 parts of fly ash, and 6 parts of silica fume;

[0056] Machine - made sand, acrylic emulsion, modified rubber particle - polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water - reducing agent, and moisture - retaining thickener are taken and stirred evenly to obtain slag - modified rubber cement mortar;

[0057] The slag - modified rubber cement mortar comprises the following components by weight: 50 parts of machine - made sand, 45 parts of acrylic emulsion, 52 parts of modified rubber particle - polypropylene fiber composite, 37 parts of inorganic cementitious material, 14 parts of slag, 18 parts of deionized water, 3 parts of redispersible latex powder, 3 parts of water - reducing agent, and 1 part of moisture - retaining thickener;

[0058] Step 2: Preparation of rubber particle - polypropylene fiber composite:

[0059] Polypropylene fibers are taken and added to a sodium hydroxide solution with a mass fraction of 4%, soaked for 5 h, taken out and washed to obtain alkali - treated polypropylene fibers; then the alkali - treated polypropylene fibers are impregnated in styrene - acrylic emulsion for 40 min, and the mass ratio of the alkali - treated polypropylene fibers to the styrene - acrylic emulsion is 1:2; taken out and washed to obtain pretreated polypropylene fibers;

[0060] 30 g of rubber particles and 1000 mL of deionized water are taken, ultrasonically dispersed for 2 h, 1 g of dopamine is added, stirred for 40 min, 1.2 g of tris - hydroxymethyl aminomethane buffer solution is added, the pH value is adjusted to 8.5 with hydrochloric acid, stirred evenly, 7 g of pretreated polypropylene fibers and 10 g of mercaptoacetic acid are added, stirred for 24 h, centrifuged, washed, and dried to obtain rubber particle - polypropylene fiber composite;

[0061] Step 3: Preparation of sodium silicate solution:

[0062] Take 100 g of water glass solution, 3.5 g of silicon phosphate, 5 g of vinyltrimethoxysilane, 1 g of urea, 1 g of hydroxypropyl methylcellulose, and 2 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone, stir evenly to obtain a water glass solution;

[0063] Step Four: Preparation of modified rubber particle - polypropylene fiber composite:

[0064] Take the water glass solution and dilute it with deionized water into a solution with the same mass as the rubber particle - polypropylene fiber composite; then evenly spray the solution on the surface of the rubber particle - polypropylene fiber composite through a sprayer, dry it, and react under an 800W ultraviolet lamp for 40 min to obtain the modified rubber particle - polypropylene fiber composite.

[0065] Comparative Example 1: Without using dopamine to compound rubber particles and polypropylene fibers, the rest is the same as in Example 1:

[0066] Step One: Preparation of slag modified rubber cement mortar:

[0067] Mix portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material;

[0068] The inorganic cementitious material includes the following components by weight: 72 parts of portland cement, 8 parts of kaolin, 4 parts of fly ash, and 5 parts of silica fume;

[0069] Take manufactured sand, acrylic emulsion, modified rubber particle - polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture - retaining thickener, stir evenly to obtain slag modified rubber cement mortar;

[0070] The slag modified rubber cement mortar includes the following components by weight: take 47 parts of manufactured sand, 42 parts of acrylic emulsion, 47 parts of modified rubber particle - polypropylene fiber composite, 35 parts of inorganic cementitious material, 13 parts of slag, 16 parts of deionized water, 2.5 parts of redispersible latex powder, 2.5 parts of water reducer, and 0.8 part of moisture - retaining thickener;

[0071] Step Two: Preparation of rubber particle - polypropylene fiber composite:

[0072] Take polypropylene fibers, add them to a sodium hydroxide solution with a mass fraction of 4%, soak for 4 h, take out and wash to obtain alkali - treated polypropylene fibers; then put the alkali - treated polypropylene fibers into styrene - acrylic emulsion for impregnation for 35 min, and the mass ratio of the alkali - treated polypropylene fibers to the styrene - acrylic emulsion is 1:2; take out and wash to obtain pretreated polypropylene fibers;

[0073] Take 30 g of rubber particles and 1000 mL of deionized water, ultrasonically disperse for 1.5 h, add 7 g of pretreated polypropylene fibers and 10 g of mercaptoacetic acid, stir for 23 h, centrifuge, wash, and dry to obtain a rubber particle-polypropylene fiber composite;

[0074] Step 3: Preparation of the sodium silicate solution:

[0075] Take 100 g of sodium silicate water, 3.5 g of silicon phosphate, 5 g of vinyltrimethoxysilane, 1 g of urea, 1 g of hydroxypropyl methylcellulose, and 2 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone, stir evenly to obtain a sodium silicate solution;

[0076] Step 4: Preparation of the modified rubber particle-polypropylene fiber composite:

[0077] Take the sodium silicate solution and dilute it with deionized water into a solution with the same mass as the rubber particle-polypropylene fiber composite; then evenly spray the solution on the surface of the rubber particle-polypropylene fiber composite through a sprayer, dry, and react under an 800 W ultraviolet lamp for 35 min to obtain a modified rubber particle-polypropylene fiber composite.

[0078] Comparative Example 2: Do not spray the sodium silicate solution on the surface of the rubber particle-polypropylene fiber composite, and the rest is the same as in Example 1:

[0079] Step 1: Preparation of slag-modified rubberized cement mortar:

[0080] Mix portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material;

[0081] The inorganic cementitious material includes the following components, by weight: 72 parts of portland cement, 8 parts of kaolin, 4 parts of fly ash, 5 parts of silica fume;

[0082] Take manufactured sand, acrylic emulsion, rubber particle-polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture-retaining thickener, stir evenly to obtain slag-modified rubberized cement mortar;

[0083] The slag-modified rubberized cement mortar includes the following components, by weight: take 47 parts of manufactured sand, 42 parts of acrylic emulsion, 47 parts of rubber particle-polypropylene fiber composite, 35 parts of inorganic cementitious material, 13 parts of slag, 16 parts of deionized water, 2.5 parts of redispersible latex powder, 2.5 parts of water reducer, and 0.8 part of moisture-retaining thickener;

[0084] Step 2: Preparation of the rubber particle-polypropylene fiber composite:

[0085] Take polypropylene fibers and add them to a sodium hydroxide solution with a mass fraction of 4%. Soak for 4 h, take out and wash to obtain alkali-treated polypropylene fibers. Then immerse the alkali-treated polypropylene fibers in styrene-acrylic emulsion for 35 min. The mass ratio of the alkali-treated polypropylene fibers to the styrene-acrylic emulsion is 1:2. Take out and wash to obtain pretreated polypropylene fibers.

[0086] Take 30 g of rubber particles and 1000 mL of deionized water, ultrasonically disperse for 1.5 h, add 1 g of dopamine, stir for 30 min, add 1.2 g of tris(hydroxymethyl)aminomethane buffer solution, adjust the pH value to 8.4 with hydrochloric acid, stir evenly, add 7 g of pretreated polypropylene fibers and 10 g of mercaptoacetic acid, stir for 23 h, centrifuge, wash and dry to obtain rubber particle-polypropylene fiber composites.

[0087] Comparative Example 3: Vinyltrimethoxysilane is not added to the sodium silicate solution, and the rest is the same as in Example 1.

[0088] Step 1: Preparation of slag-modified rubber cement mortar:

[0089] Mix portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material.

[0090] The inorganic cementitious material includes the following components by weight: 72 parts of portland cement, 8 parts of kaolin, 4 parts of fly ash, and 5 parts of silica fume.

[0091] Take manufactured sand, acrylic emulsion, modified rubber particle-polypropylene fiber composites, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture-retaining thickener, and stir evenly to obtain slag-modified rubber cement mortar.

[0092] The slag-modified rubber cement mortar includes the following components by weight: take 47 parts of manufactured sand, 42 parts of acrylic emulsion, 47 parts of modified rubber particle-polypropylene fiber composites, 35 parts of inorganic cementitious material, 13 parts of slag, 16 parts of deionized water, 2.5 parts of redispersible latex powder, 2.5 parts of water reducer, and 0.8 part of moisture-retaining thickener.

[0093] Step 2: Preparation of rubber particle-polypropylene fiber composites:

[0094] Take polypropylene fibers and add them to a sodium hydroxide solution with a mass fraction of 4%. Soak for 4 h, take out and wash to obtain alkali-treated polypropylene fibers. Then immerse the alkali-treated polypropylene fibers in styrene-acrylic emulsion for 35 min. The mass ratio of the alkali-treated polypropylene fibers to the styrene-acrylic emulsion is 1:2. Take out and wash to obtain pretreated polypropylene fibers.

[0095] Take 30 g of rubber particles and 1000 mL of deionized water, ultrasonically disperse for 1.5 h, add 1 g of dopamine, stir for 30 min, add 1.2 g of tris(hydroxymethyl)aminomethane buffer solution, add hydrochloric acid to adjust the pH value to 8.4, stir evenly, add 7 g of pretreated polypropylene fibers and 10 g of mercaptoacetic acid, stir for 23 h, centrifuge, wash, and dry to obtain rubber particle-polypropylene fiber composites;

[0096] Step 3: Preparation of sodium silicate solution:

[0097] Take 100 g of sodium silicate solution, 3.5 g of silicon phosphate, 1 g of urea, 1 g of hydroxypropyl methylcellulose, and 2 g of 2-hydroxy-2-methyl-1-phenyl-1-propanone, stir evenly to obtain a sodium silicate solution;

[0098] Step 4: Preparation of modified rubber particle-polypropylene fiber composites:

[0099] Take the sodium silicate solution and dilute it with deionized water into a solution with the same mass as the rubber particle-polypropylene fiber composites; then evenly spray the solution on the surface of the rubber particle-polypropylene fiber composites through a sprayer, dry, and react under an 800 W ultraviolet lamp for 35 min to obtain modified rubber particle-polypropylene fiber composites.

[0100] Experiment:

[0101] Take the slag-modified rubber cement mortars prepared in Examples 1 to 3 and Comparative Examples 1 to 3, under the conditions of 23 °C and a relative humidity of 60%, cure at constant temperature and humidity for 28 days to form specimens of 40 mm × 40 mm × 160 mm, and then conduct performance tests; apply a uniform load at a speed of 2400 N / s ± 200 N / S to test the compressive strength; the obtained data are shown in Table 1 below:

[0102] Table 1

[0103] Compressive strength / Mpa Sound absorption coefficient Example 1 11.3 0.42 Example 2 11.0 0.40 Example 3 11.5 0.43 Comparative Example 1 10.6 0.38 Comparative Example 2 9.2 0.39 Comparative Example 3 10.1 0.40

[0104] Conclusion: It can be seen from the comparison of the data in the table that in Comparative Example 1, dopamine is not used to compound rubber particles and polypropylene fibers, the dispersibility of polypropylene fibers becomes poor, and the mechanical properties of slag-modified rubberized cement mortar decrease. In Comparative Example 2, sodium silicate solution is not sprayed on the surface of the rubber particle-polypropylene fiber composite, and the mechanical properties of the cement mortar decrease significantly. In Comparative Example 3, vinyltrimethoxysilane is not added to the sodium silicate solution, the binding ability between the rubber particle-polypropylene fiber composite and the sodium silicate solution decreases, and the mechanical properties of the cement mortar become poor. In Examples 1-3 of the present invention, dopamine is used to compound rubber particles and polypropylene fibers. The use of dopamine also improves the hydrophilicity of the rubber particle-polypropylene fiber composite, enabling the sodium silicate solution to be better loaded on the surface of the rubber particle-polypropylene fiber composite, thereby enhancing the mechanical properties of the cement mortar. Spraying sodium silicate solution on the surface of the rubber particle-polypropylene fiber composite improves the interfacial bonding of the rubber particle-polypropylene fiber composite, thereby enhancing the mechanical properties of the cement mortar, and the compressive strength can reach 11 Mpa.

[0105] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A preparation process of slag-modified rubber cement mortar, characterized in that: It includes the following steps: Step 1: Mix portland cement, kaolin, fly ash, and silica fume evenly to obtain an inorganic cementitious material; Step 2: Take manufactured sand, acrylic emulsion, modified rubber particle - polypropylene fiber composite, inorganic cementitious material, slag, deionized water, redispersible latex powder, water reducer, and moisture - retaining thickener, and stir evenly to obtain slag - modified rubberized cement mortar.

2. The preparation process of a slag-modified rubber cement mortar according to claim 1, characterized in that: The inorganic cementitious material includes the following components by weight: 70 - 75 parts of portland cement, 6 - 10 parts of kaolin, 3 - 5 parts of fly ash, and 3 - 6 parts of silica fume; The slag - modified rubberized cement mortar includes the following components by weight: Take 45 - 50 parts of manufactured sand, 40 - 45 parts of acrylic emulsion, 45 - 52 parts of modified rubber particle - polypropylene fiber composite, 30 - 37 parts of inorganic cementitious material, 12 - 14 parts of slag, 15 - 18 parts of deionized water, 2 - 3 parts of redispersible latex powder, 2 - 3 parts of water reducer, and 0.5 - 1 part of moisture - retaining thickener.

3. The preparation process of a slag-modified rubber cement mortar according to claim 2, characterized in that: The preparation method of the modified rubber particle - polypropylene fiber composite is as follows: Dilute the sodium silicate solution with deionized water into a solution with the same mass as the rubber particle - polypropylene fiber composite; then spray the solution on the surface of the rubber particle - polypropylene fiber composite, dry it, and react under an ultraviolet lamp for 30 - 40 min to obtain the modified rubber particle - polypropylene fiber composite.

4. The preparation process of a slag-modified rubber cement mortar according to claim 3, characterized in that: The preparation method of the rubber particle - polypropylene fiber composite is as follows: Take rubber particles and deionized water, ultrasonically disperse for 1 - 2 h, add dopamine, stir for 20 - 40 min, add tris - hydroxymethyl aminomethane buffer solution, adjust the pH value to 8.3 - 8.5 with hydrochloric acid, stir evenly, add pretreated polypropylene fiber and mercaptoacetic acid, stir for 22 - 24 h, centrifuge, wash, and dry to obtain the rubber particle - polypropylene fiber composite.

5. The preparation process of a slag-modified rubber cement mortar according to claim 3, characterized in that: The preparation method of the sodium silicate solution is as follows: Take sodium silicate water, phosphosilicate, vinyltrimethoxysilane, urea, hydroxypropyl methylcellulose, 2 - hydroxy - 2 - methyl - 1 - phenyl - 1 - propanone, and stir evenly to obtain the sodium silicate solution.

6. The preparation process of a slag-modified rubber cement mortar according to claim 4, characterized in that: The preparation method of the pretreated polypropylene fiber is as follows: Take polypropylene fiber, add it to a sodium hydroxide solution, soak for 3 - 5 h, take it out and wash to obtain the alkali - treated polypropylene fiber; Then immerse the alkali - treated polypropylene fiber in styrene - acrylic emulsion for 30 - 40 min, take it out and wash to obtain the pretreated polypropylene fiber.

7. The preparation process of a slag-modified rubber cement mortar according to claim 2, characterized in that: The water reducer is a polycarboxylate water reducer; the moisture - retaining thickener is hydroxypropyl methylcellulose ether.

8. The preparation process of a slag-modified rubber cement mortar according to claim 4, characterized in that: The particle size of the rubber particles is 10 - 20 mesh.

9. The slag - modified rubberized cement mortar prepared by the preparation process of a slag - modified rubberized cement mortar according to any one of claims 1 - 8.