A polymer-based anti-permeation alkali-resistant paste and a preparation method thereof

Abstract

The application relates to the technical field of waterproof slurry and discloses a polymer-based anti-seepage alkali-resistant slurry and a preparation method thereof, wherein the polymer-based anti-seepage alkali-resistant slurry comprises the following raw material components in proportion by weight: 300-350 parts of butylphenyl emulsion, 50-100 parts of acrylic emulsion, 6-10 parts of acrylic dispersant, 6-10 parts of 2-methyl acryloyl oxyethyl phosphocholine, 200-300 parts of fillers, 1-3 parts of film-forming aids, 0.5-2 parts of initiators, 0.5-2 parts of sodium hydroxide and 200 parts of water; the fillers comprise heavy calcium, precipitated barium sulfate and pseudo-boehmite. The butylphenyl emulsion and the acrylic emulsion are compounded, the fillers are filled, and the initiators are crosslinked, so that the compounded slurry has good flexibility, bending and compressive strength and bonding performance at the same time, the waterproof layer is more compact, the anti-seepage alkali resistance is better, and the operation is safe and convenient.

Description

Technical Field

[0001] This invention relates to the technical field of waterproof slurry, and in particular to a polymer-based waterproof and alkali-resistant slurry and its preparation method. Background Technology

[0002] Building quality engineering issues are closely related to waterproofing and damp-proofing, including basement waterproofing and damp-proofing in various buildings, waterproofing at joints of various finishing materials, and waterproofing and mildew prevention on the surfaces of various interior and exterior wall decoration materials. Currently, waterproof mortar is commonly used for surface protection and reinforcement of joints. Applying it will not damage the original wall surface, but it provides excellent waterproofing and damp-proofing effects.

[0003] Styrene-butadiene (SBR) emulsions are copolymerized from butadiene and styrene emulsions. They are very stable under alkaline conditions and do not hydrolyze. Therefore, SBR waterproof mortar emulsions have good water and alkali resistance, rigidity, and good bonding strength, compressive and flexural strength, as well as compatibility and adhesion with cement. However, they have poor flexibility. Acrylic emulsions are emulsions copolymerized from pure acrylate monomers. Because the ester groups of acrylate monomers hydrolyze under strongly alkaline conditions, they have poor water and alkali resistance, but their flexibility is better than that of SBR emulsions. Therefore, the two existing polymer-based waterproof mortar emulsions cannot simultaneously achieve comprehensive performance such as flexibility, flexural and compressive strength, bonding strength, and acid and alkali resistance, making it difficult to meet market needs.

[0004] Chinese invention patent CN 111138600 B discloses a styrene-butadiene modified zero-ammonia acrylic waterproof mortar emulsion, its preparation method, and the waterproof mortar itself. The waterproof mortar emulsion comprises 100 parts deionized water, 25-35 parts styrene, 50-60 parts butyl acrylate, 1-5 parts hydroxyethyl acrylate, 1-3 parts hydroxyethyl methacrylate, 0.5-3 parts methacrylic acid, 0.1-0.5 parts allyl methacrylate, 0.1-0.5 parts silane coupling agent, 55-65 parts styrene-butadiene emulsion, 1-10 parts emulsifier, 0.1-1 part initiator, and 0.1-2 parts sodium hydroxide. However, this waterproof mortar emulsion suffers from poor flexural and compressive strength due to the high proportion of acrylic emulsion added, and the large number of ester groups it contains will hydrolyze under strongly alkaline conditions, resulting in poor water and alkali resistance. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a polymer-based waterproof and alkali-resistant slurry and its preparation method. By compounding styrene-butadiene emulsion and acrylic emulsion, and simultaneously adding dispersants, fillers, and additives, a waterproof layer with superior flexural and compressive strength, flexibility, and bonding strength can be obtained through the synergistic effect of multiple agents. It also exhibits good water and alkali resistance, making it suitable for surface protection and waterproof reinforcement of various buildings.

[0006] The objective of this invention is achieved through the following technical solution: In a first aspect, the present invention provides a polymer-based impermeable and alkali-resistant slurry, comprising, by weight, the following raw material components: 300-350 parts of styrene-butadiene emulsion, 50-100 parts of acrylic emulsion, 6-10 parts of acrylic dispersant, 6-10 parts of 2-methacryloyloxyethyl phosphocholine, 200-300 parts of filler, 1-3 parts of film-forming aid, 0.5-2 parts of initiator, 0.5-2 parts of sodium hydroxide, and 200 parts of water; wherein the filler comprises heavy calcium carbonate, precipitated barium sulfate, and pseudoboehmite.

[0007] This invention, through the compounding of styrene-butadiene emulsion and acrylic emulsion, enables the compounded slurry to simultaneously possess excellent flexibility, rigidity, and bonding properties. Even with the presence of ester groups in the acrylic emulsion, the cement waterproof mortar maintains good waterproof and alkali-resistant properties under long-term strongly alkaline conditions due to the high proportion of styrene-butadiene emulsion. The addition of filler provides excellent filling effect, making the waterproof layer more compact and thus improving flexural and compressive strength. Moreover, the filler, a compound of heavy calcium carbonate, precipitated barium sulfate, and boehmite, allows for better filling effects through different material, quality, and particle size ratios. The added 2-methacryloyloxyethyl phosphocholine carries both positive and negative charges, resulting in better compatibility and adsorption with the filler components, as well as strong water-binding and hydrophilic properties. The boehmite in the filler can also bind water to form a sol, providing better bonding. Furthermore, the acrylic dispersant, 2-methacryloyloxyethyl phosphocholine, and some double bonds in the styrene-butadiene emulsion can undergo cross-linking under the action of the initiator, increasing the proportion of flexible segments and improving flexibility to a certain extent. Moreover, the synergistic effect of multiple actions leads to better bonding between the components and improved dispersion uniformity. The slurry formulation of this invention exhibits better crack resistance during the waterproofing layer forming process, prevents drying, and improves recoating properties, thereby achieving superior flexural and compressive strength, flexibility, and adhesive strength.

[0008] Preferably, the filler comprises heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1.

[0009] Preferably, the particle size of the heavy calcium carbonate is 200-500 mesh; the particle size of the precipitated barium sulfate is 1250-3000 mesh; and the particle size of the pseudoboehmite is no greater than 10 nm.

[0010] Different materials, qualities, and particle size ratios can enable fillers to achieve better filling effects. Furthermore, the smallest particle size of boehmite and its ability to act as a binder result in better filling effects and higher structural stability.

[0011] Preferably, the solid content of the styrene-butadiene emulsion is 45-50%, and the viscosity is 100-200 mPa·s.

[0012] Preferably, the acrylic emulsion has a solid content of 55-60% and a viscosity of 300-500 mPa·s.

[0013] Under these specific conditions, the blending of styrene-butadiene emulsion and acrylic emulsion can better balance flexibility and flexural and compressive strength, resulting in better overall performance.

[0014] Preferably, the acrylic dispersant includes one or more of acrylic acid, methacrylic acid, and 2-ethylacrylic acid.

[0015] Preferably, the film-forming aid is 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.

[0016] Preferably, the initiator is sodium persulfate, potassium persulfate, or ammonium persulfate.

[0017] Preferably, the product also includes the following raw material components by weight: 1 to 3 parts of defoamer and 0.1 to 1 part of bactericide.

[0018] Preferably, the defoamer is an organosilicone defoamer.

[0019] Preferably, the bactericide is an isothiazolinone bactericide.

[0020] Secondly, the present invention also provides a method for preparing a polymer-based impermeable and alkali-resistant slurry, comprising the following steps: (1) Mix acrylic dispersant, defoamer and 80-90% by weight of water to obtain a first solution; (2) Mix the initiator with the remaining weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70-80% by weight of initiator solution, stir at low speed and heat to 70-80℃ for 60-90 min. (4) Add heavy calcium carbonate and the remaining initiator solution, stir at high speed and keep the temperature at 70-80℃ for 10-20 minutes; (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust the pH to 7-9, stir for 30-60 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0021] Preferably, in step (3), the low-speed stirring speed is 100-150 r / min.

[0022] Preferably, in step (4), the speed of high-speed stirring is 200-300 r / min.

[0023] Compared with the prior art, the present invention has the following beneficial effects: (1) By combining styrene-butadiene emulsion and acrylic emulsion, the compounded mortar can simultaneously possess good flexibility, rigidity and bonding properties, and the waterproof and alkali-resistant properties of cement waterproof mortar are good. (2) The filler, which is composed of heavy calcium carbonate, precipitated barium sulfate and pseudoboehmite, can play a good filling role, making the waterproof layer more compact and thus having better flexural and compressive strength. (3) The addition of 2-methacryloyloxyethyl phosphocholine can improve the compatibility and adsorption of the filler components, while also having a strong ability to bind water and hydrophilic properties. In addition, the synergistic crosslinking with other components increases the proportion of flexible segments, resulting in better bonding and dispersion uniformity among the components.

[0024] (4) The polymer-based anti-seepage and alkali-resistant slurry obtained by the present invention has good environmental protection, safe operation, convenient construction, and excellent adhesion to structural base and various building materials. Detailed Implementation

[0025] The technical solution of the present invention is illustrated below with specific embodiments, but the scope of protection of the present invention is not limited thereto: By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes 300-350 parts of styrene-butadiene emulsion, 50-100 parts of acrylic emulsion, 6-10 parts of acrylic dispersant, 6-10 parts of 2-methacryloyloxyethyl phosphocholine, 200-300 parts of filler, 1-3 parts of film-forming aid, 0.5-2 parts of initiator, 0.5-2 parts of sodium hydroxide, 1-3 parts of defoamer, 0.1-1 parts of bactericide, and 200 parts of water.

[0026] The solid content of the styrene-butadiene emulsion is 45-50%, and the viscosity is 100-200 mPa·s.

[0027] The acrylic emulsion has a solid content of 55-60% and a viscosity of 300-500 mPa·s.

[0028] Acrylic dispersants include one or more of acrylic acid, methacrylic acid, and 2-ethylacrylic acid.

[0029] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The particle size of the heavy calcium carbonate is 200–500 mesh, the particle size of the precipitated barium sulfate is 1250–3000 mesh, and the particle size of the boehmite is no greater than 10 nm.

[0030] The film-forming aid is 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.

[0031] The initiator is sodium persulfate, potassium persulfate, or ammonium persulfate.

[0032] The defoamer is an organosilicone defoamer.

[0033] The bactericide is an isothiazolinone bactericide.

[0034] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix acrylic dispersant, defoamer and 80-90% by weight of water to obtain a first solution; (2) Mix the initiator with the remaining weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70-80% by weight of initiator solution, stir at a low speed of 100-150 r / min, and heat to 70-80℃ for 60-90 min. (4) Add the heavy calcium carbonate and the remaining initiator solution, stir at a high speed of 200-300 r / min, and keep the temperature at 70-80℃ for 10-20 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 7-9, stir for 30-60 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0035] Example 1 By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 8 parts of 2-methacryloyloxyethyl phosphocholine, 250 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0036] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0037] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0038] Example 2 By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 350 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 50 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 6 parts of acrylic dispersant (methacrylic acid), 6 parts of 2-methacryloyloxyethyl phosphocholine, 200 parts of filler, 1 part of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 0.5 parts of initiator (potassium persulfate), 1.5 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0039] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0040] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0041] Example 3 By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 10 parts of acrylic dispersant (methacrylic acid), 10 parts of 2-methacryloyloxyethyl phosphocholine, 300 parts of filler, 1 part of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0042] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0043] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0044] Example 4 By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 8 parts of 2-methacryloyloxyethyl phosphocholine, 250 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0045] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0046] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 80% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 80℃ for 70 min. (4) Add the heavy calcium carbonate and the remaining 20% ​​by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 75℃ for 20 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0047] Comparative Example 1 The difference from Example 1 is that 2-methacryloyloxyethyl phosphocholine was not added.

[0048] By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 250 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0049] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0050] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, precipitated barium sulfate and pseudoboehmite to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0051] Comparative Example 2 The difference from Example 1 is that no boehmite was added.

[0052] By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 8 parts of 2-methacryloyloxyethyl phosphocholine, 229 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0053] The filler consists of heavy calcium carbonate and precipitated barium sulfate in a weight ratio of 10:1. The heavy calcium carbonate has a particle size of 500 mesh, and the precipitated barium sulfate has a particle size of 3000 mesh.

[0054] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine and precipitated barium sulfate to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0055] Comparative Example 3 The difference from Example 1 is that the amount and proportion of filler added are different.

[0056] By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 8 parts of 2-methacryloyloxyethyl phosphocholine, 200 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0057] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 8:2:2. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0058] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0059] Comparative Example 4 The difference from Example 1 is that the amount of styrene-butadiene emulsion added is less.

[0060] By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: The composition includes: 250 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 8 parts of 2-methacryloyloxyethyl phosphocholine, 250 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (organosilicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), and 200 parts of water.

[0061] The filler consists of heavy calcium carbonate, precipitated barium sulfate, and boehmite in a weight ratio of 10:1:1. The heavy calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the boehmite has an average particle size of 10 nm.

[0062] The preparation of the above-mentioned polymer-based waterproof and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, the defoamer and 80% by weight of water to obtain the first solution; (2) Mix the initiator with the remaining 20% ​​by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and boehmite to the first solution and stir to mix. Then add 70% by weight of initiator solution, stir at a low speed of 150 r / min, and heat to 70℃ for 90 min. (4) Add the heavy calcium carbonate and the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and keep the temperature at 80℃ for 15 min. (5) After cooling, add bactericide and film-forming aid, add sodium hydroxide to adjust pH to 8-9, stir for 50 minutes, filter and discharge to obtain polymer-based impermeable and alkali-resistant slurry.

[0063] Comparative Example 5 The difference from Example 1 is that the order in which the filler is added is different.

[0064] By weight, polymer-based waterproofing and alkali-resistant slurry comprises the following raw material components: 300 parts of styrene-butadiene emulsion (C3615, solid content 49%, viscosity 200 mPa·s), 100 parts of acrylic emulsion (S400, solid content 57%, viscosity 400 mPa·s), 8 parts of acrylic dispersant (methacrylic acid), 8 parts of 2-methacryloyloxyethyl phosphorylcholine, 250 parts of filler, 1.5 parts of film-forming aid (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), 1 part of initiator (potassium persulfate), 1.2 parts of sodium hydroxide, 2 parts of defoamer (silicone defoamer MSD-916), 0.4 parts of bactericide (isothiazolinone), 200 parts of water.

[0065] The filler comprises ground calcium carbonate, precipitated barium sulfate and pseudo-boehmite in a weight ratio of 10:1:1. The ground calcium carbonate has a particle size of 500 mesh, the precipitated barium sulfate has a particle size of 3000 mesh, and the pseudo-boehmite has an average particle size of 10 nm.

[0066] The preparation of the above polymer-based anti-seepage and alkali-resistant slurry includes the following steps: (1) Mix the acrylic dispersant, defoamer and 80% by weight of water to obtain a first solution; (2) Mix the initiator and the remaining 20% by weight of water to obtain an initiator solution; (3) Add styrene-butadiene emulsion, acrylic emulsion, 2-methacryloyloxyethyl phosphorylcholine, precipitated barium sulfate, pseudo-boehmite and ground calcium carbonate to the first solution, stir and mix, then add 70% by weight of the initiator solution, stir at a low speed of 150 r / min, and heat to 70°C for reaction for 90 min; (4) Add the remaining 30% by weight of the initiator solution, stir at a high speed of 250 r / min, and maintain the temperature at 80°C for reaction for 15 min; (5) After cooling, add the bactericide and the film-forming aid, add sodium hydroxide to adjust the pH to 8-9, stir for 50 min, filter and discharge to obtain the polymer-based anti-seepage and alkali-resistant slurry.

[0067] Performance tests are carried out based on "JC / T 2090-2011 Polymer Cement Waterproof Slurry". The coating film thickness of the slurry is 1.5 mm, and the film is cured under the environmental conditions of 23°C and 50% humidity.

[0068] Among them, the alkali resistance test is conducted by scraping and coating the slurry onto a (70×70×20) mm cement mortar block with a thickness of 1.5 mm, curing to the age of 7 days, and then immersing the block in a saturated calcium hydroxide solution for 168 h. Subsequently, take out the test specimen and observe for cracks and spallation. If there is no crack or spallation, it is judged as qualified. According to the degree of cracks and spallation from excellent to poor, the grades are: slight cracking and spallation, partial cracking and spallation, and severe cracking and spallation.

[0069] Table 1 As shown in Table 1, the waterproof membrane obtained by the polymer-based seepage-proof and alkali-resistant slurry in this invention has good flexibility, flexural and compressive strength, seepage resistance, bonding strength and alkali resistance.

[0070] Comparative Example 1 shows that 2-methacryloyloxyethyl phosphocholine mainly affects the compatibility and cross-linking structure of each component, thus having a certain impact on the mechanical properties and alkali resistance of the waterproof membrane. Comparative Example 2 shows that boehmite mainly affects the filling effect of the filler and its dispersion and bonding in the matrix, thus having a greater impact on flexural and compressive strength and impermeability. Comparative Example 3 shows that the proportion of heavy calcium carbonate in the filler is relatively small. Because it has a significant impact on the filling effect of the filler, it also has a greater impact on the alkali resistance of the waterproof membrane compared to Comparative Example 2. In Comparative Example 4, the small proportion of styrene-butadiene emulsion will lead to a significant reduction in flexibility, impermeability, and alkali resistance. In Comparative Example 5, the change in the order of filler addition, due to the large amount of heavy calcium carbonate added before the cross-linking is initiated, will affect the cross-linking effect, worsen the internal structural stability, and lead to a decrease in the mechanical properties and alkali resistance of the waterproof membrane.

[0071] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made using the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for preparing a polymer-based impermeable and alkali-resistant slurry, characterized in that, By weight, including: (1) Mix 6-10 parts of acrylic dispersant, 1-3 parts of defoamer and 80-90% by weight of water, with a total water content of 200 parts. The acrylic dispersant includes one or more of acrylic acid, methacrylic acid and 2-ethylacrylic acid to obtain a first solution. (2) Mix 0.5 to 2 parts of initiator with the remaining parts by weight of water to obtain an initiator solution; (3) Add 300-350 parts of styrene-butadiene emulsion, 50-100 parts of acrylic emulsion, 6-10 parts of 2-methacryloyloxyethyl phosphocholine, precipitated barium sulfate and pseudoboehmite to the first solution and stir to mix. Add 70-80% by weight of initiator solution, stir at low speed and heat to 70-80℃ for 60-90 min. (4) Add the heavy calcium carbonate and the remaining weight of the initiator solution. The weight ratio of heavy calcium carbonate, precipitated barium sulfate and pseudoboehmite is 10:1:1 and the total number of parts is 200~300. Stir at high speed and keep the temperature at 70~80℃ for 10~20 min. (5) After cooling, add 0.1 to 1 part of bactericide and 1 to 3 parts of film-forming aid, add 0.5 to 2 parts of sodium hydroxide to adjust the pH to 7 to 9, stir for 30 to 60 minutes, and filter.

2. The method for preparing the polymer-based waterproof and alkali-resistant slurry according to claim 1, characterized in that, The particle size of the calcium carbonate is 200-500 mesh.

3. The method for preparing the polymer-based waterproof and alkali-resistant slurry according to claim 1, characterized in that, The precipitated barium sulfate has a particle size of 1250~3000 mesh.

4. The method for preparing the polymer-based waterproof and alkali-resistant slurry according to claim 1, characterized in that, The particle size of the pseudoboehmite is no greater than 10 nm.

5. The method for preparing the polymer-based impermeable and alkali-resistant slurry according to claim 1, characterized in that, The solid content of the styrene-butadiene emulsion is 45-50%, and the viscosity is 100-200 mPa·s.

6. The method for preparing the polymer-based impermeable and alkali-resistant slurry according to claim 1, characterized in that, The acrylic emulsion has a solid content of 55-60% and a viscosity of 300-500 mPa·s.

7. The method for preparing the polymer-based waterproof and alkali-resistant slurry according to claim 1, characterized in that, The defoamer is an organosilicone defoamer.

8. The method for preparing the polymer-based waterproof and alkali-resistant slurry according to claim 1 or 7, characterized in that, The bactericide is an isothiazolinone bactericide.

9. The method for preparing the polymer-based waterproof and alkali-resistant slurry according to claim 1, characterized in that, In step (3), the speed of low-speed stirring is 100~150 r / min; in step (4), the speed of high-speed stirring is 200~300 r / min.

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