High-elastic waterproof emulsion and preparation method thereof

Abstract

The application relates to the technical field of waterproof materials, and specifically discloses a high-elasticity waterproof emulsion and a preparation method thereof. The high-elasticity waterproof emulsion is prepared from the following raw materials in parts by mass: modified acrylic resin emulsion 40-60 parts, water-based polyurethane 25-40 parts, hydroxyethyl methacrylate 3-6 parts, mercapto propionic acid 0.5-1 part, fluorinated mica sheet 6-8 parts, silicone emulsion 3-6 parts, fluorocarbon surfactant 2-4 parts, adipic acid dihydrazide 0.8-1.5 parts, dynamic crosslinking agent 0.3-0.8 parts, compatilizer 3-8 parts, antioxidant 0.5-1 part, anti-aging agent 0.5-1 part, defoaming agent 0.5-1.5 parts and solvent 40-55 parts; and the modified acrylic resin emulsion is prepared from monomers including diacetone acrylamide. The high-elasticity waterproof emulsion prepared by the application has good elasticity, waterproof performance and aging resistance.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of waterproof materials, and more particularly to a high-elasticity waterproof emulsion and a preparation method thereof. BACKGROUND

[0002] As the core material of building waterproof engineering, the core value of the elastic waterproof emulsion lies in realizing dynamic adaptation to the deformation of the base material through the flexible design and network structure regulation of the polymer chain, so as to block the water permeation path. Common elastic waterproof emulsions can be divided into three categories according to the types of the base polymer: polymer emulsion waterproof emulsion, polyurethane waterproof emulsion and acrylate waterproof emulsion. Although these three types of emulsions have their own advantages, they still face common challenges in practical application, such as the long-term elastic retention of the polymer emulsion, the low-temperature construction of the polyurethane emulsion and the dynamic crack resistance of the acrylate resin emulsion. These technical difficulties also drive the continuous innovation of the elastic waterproof emulsion in the direction of 'higher elasticity, better weather resistance and wider adaptation'.

[0003] The patent application file with the publication number CN119875413A discloses a high-elasticity waterproof coating, which comprises the following raw materials in parts by mass: acrylic emulsion 50-60 parts, N-hydroxymethyl acrylamide 0.2-0.96 parts, diacetone acrylamide 0.3-2.04 parts, adipoyl dihydrazide 0.1-3.5 parts, preservative 0.1-0.15 parts, inorganic filler 20-40 parts, defoaming agent 0.5-2 parts, gelatin 5-12 parts, glycerol 0.3-0.48 parts, natural fiber 0.1-0.36 parts, gluconolactone 2-4.8 parts and coupling agent 1-5 parts.

[0004] In the technical solution, the base material system mainly composed of acrylic emulsion is crosslinked only by diacetone acrylamide and adipoyl dihydrazide. Such a single rigid crosslinking structure makes it difficult for the coating to release stress under repeated deformation, and permanent deformation is prone to occur. Gelatin can absorb environmental moisture, causing the coating to swell and destroy the compactness, resulting in micro-cracks in the coating. Although glycerol as a small molecule plasticizer can temporarily improve the initial flexibility, it is easy to migrate to the surface of the coating over time, and the coating gradually hardens and becomes brittle, and is more prone to cracking under low temperature or high frequency deformation. SUMMARY

[0005] In order to balance the mechanical properties, the application provides a high-elasticity waterproof emulsion and a preparation method thereof.

[0006] In the first aspect, the application provides a high-elasticity waterproof emulsion, which adopts the following technical solution:

[0007] A high-elastic waterproof emulsion is prepared from the following raw materials by mass: modified acrylic resin emulsion 40-60 parts, water-based polyurethane 25-40 parts, hydroxyethyl methacrylate 3-6 parts, mercaptopropionic acid 0.5-1 part, fluorinated mica sheet 6-8 parts, silicone emulsion 3-6 parts, fluorocarbon surfactant 2-4 parts, adipic acid dihydrazide 0.8-1.5 parts, dynamic crosslinking agent 0.3-0.8 parts, compatibilizer 3-8 parts, antioxidant 0.5-1 part, anti-aging agent 0.5-1 part, defoaming agent 0.5-1.5 parts and solvent 40-55 parts.

[0008] The modified acrylic resin emulsion is prepared from monomers including diacetone acrylamide.

[0009] In the technical solution, the modified acrylic resin emulsion and the water-based polyurethane are base materials, and the two are molecularly compatible through the compatibilizer to avoid phase separation, effectively improve the elongation at break of the coating, and effectively resist physical damage such as scratching and collision. The fluorinated mica sheet is arranged directionally at the bottom of the coating layer due to the sheet structure, forming a physical barrier layer, and a low-surface-energy hydrophobic film is formed by the migration of the organic silicone emulsion and the fluorocarbon surfactant components on the surface layer, thereby constructing a gradient waterproof structure to effectively block the invasion of water and corrosive media; meanwhile, the ketone groups pre-embedded in the modified acrylic resin emulsion can form a stable and uniform crosslinking network when reacting with adipic acid dihydrazide later; and a dynamic crosslinking agent is compounded synchronously to construct a reversible bond network. The two form a reversible-permanent double network structure, the permanent network maintains the stability of the coating morphology, and the dynamic network absorbs energy and recombines to repair microcracks when deformed, thereby giving the coating high elasticity and self-repairing properties.

[0010] Preferably, the solid content of the modified acrylic resin emulsion is about 33%-36.5%.

[0011] Preferably, the compatibilizer includes styrene-butadiene-styrene block copolymer and polyurethane acrylate.

[0012] Preferably, the dynamic crosslinking agent includes furfural and N-hydroxyethyl maleimide.

[0013] Preferably, the mass ratio of the furfural and the N-hydroxyethyl maleimide is 1: (0.8-1.2).

[0014] Preferably, the antioxidant includes antioxidant 1010.

[0015] Preferably, the antioxidant further includes antioxidant 168.

[0016] Preferably, the anti-aging agent is hindered amine stabilizer 144.

[0017] Preferably, the defoaming agent is polydimethylsiloxane.

[0018] Preferably, the solvent comprises water and propylene glycol methyl ether.

[0019] Preferably, in the solvent, the mass concentration of propylene glycol methyl ether is 10% to 20%, and the rest is water.

[0020] Preferably, the modified acrylic resin emulsion is mainly prepared from raw materials including the following mass fractions:

[0021] 50 to 70 parts of butyl acrylate, 10 to 20 parts of diacetone acrylamide, 5 to 15 parts of glycidyl methacrylate, and 5 to 8 parts of double bond-containing organosilicon.

[0022] Preferably, the raw materials of the modified acrylic resin emulsion further include 6 to 8 parts of fluorinated mica flakes.

[0023] Preferably, the preparation method of the modified acrylic resin emulsion comprises the following steps in terms of mass fractions:

[0024] S11: Put 50 to 70 parts of butyl acrylate, 10 to 20 parts of diacetone acrylamide, 5 to 15 parts of glycidyl methacrylate, 5 to 8 parts of double bond-containing organosilicon, and part of the emulsifier into water, mix uniformly to obtain a pre-emulsion;

[0025] S12: Under an inert atmosphere, add the remaining emulsifier and water into a reaction kettle, adjust the pH to 5.0 to 5.5, heat to 75 to 85℃, add part of the pre-emulsion and part of the initiator, keep warm for 30 to 40 min, add the remaining pre-emulsion and the remaining initiator, keep warm for 60 to 80 min, add dodecyl mercaptan, keep warm for 30 to 40 min, cool to 55 to 65℃, adjust the pH to 7.5 to 8.0, add 6 to 8 parts of fluorinated mica flakes, mix for 80 to 100 min to obtain the modified acrylic resin emulsion.

[0026] Preferably, the double bond-containing organosilicon is any one of vinyltrimethoxysilane and vinyltriethoxysilane.

[0027] In the technical solution, butyl acrylate provides flexible segments, diacetone acrylamide forms pre-crosslinking points with adipic acid dihydrazide, glycidyl methacrylate reacts with active groups in the waterborne polyurethane to enhance the interfacial bonding force; the double bond-containing organosilicon forms siloxane segments after hydrolysis, which improves the compatibility of the resin with the waterborne polyurethane and enhances the weather resistance of the coating. The introduced fluorinated mica flakes are dispersed in advance during the synthesis of the resin, which enhances the mechanical strength and barrier property of the subsequent coating, and the resin after film formation has both toughness and impermeability.

[0028] Preferably, the amount of the emulsifier is 2.7% to 4.4% of the total mass of butyl acrylate, diacetone acrylamide, glycidyl methacrylate, and double bond-containing organosilicon.

[0029] Preferably, the initiator includes tert-butyl hydroperoxide and sodium formaldehyde sulfoxylate.

[0030] Preferably, the amount of the initiator is 2.6% to 3.8% of the total mass of butyl acrylate, diacetone acrylamide, glycidyl methacrylate and organic silicon containing double bonds.

[0031] Preferably, the method for preparing the fluorinated mica sheet comprises the following steps:

[0032] After the mica sheet is plasma-activated, it is placed in a gas phase reaction kettle, heated to 135-140℃, liquid perfluoroalkyl iodide is injected, maintained at 0.4-0.5 MPa, mixed for 180-190 min, depressurized, heated to 180-185℃, nitrogen purging for 70-80 min, and cooled to obtain the fluorinated mica sheet.

[0033] Preferably, the mass ratio of the mica sheet to perfluoroalkyl iodide is 1: (0.3-0.4).

[0034] In the technical solution, the gas phase fluorination of perfluoroalkyl iodide makes the mica sheet have both hydrophobicity and sheet barrier properties. After directional arrangement in the coating, a multi-layer physical barrier is formed, the water penetration path is prolonged, and the water resistance of the coating is effectively improved. The sheet structure disperses frictional stress, the fluorinated surface reduces the friction coefficient, and the bonding performance with the matrix is improved to avoid the peeling of the sheet layer during abrasion.

[0035] Preferably, the high-elasticity waterproof emulsion further comprises 1.5-3 parts by mass of castor oil polyester polyol.

[0036] In the technical solution, the castor oil polyester polyol is bonded and cross-linked to be embedded in the polyurethane network, and the long alkyl chain provides continuous molecular chain segment movement ability to enhance the elastic retention rate of the coating at low temperature.

[0037] Preferably, the high-elasticity waterproof emulsion further comprises 2-5 parts by mass of amino-terminated hyperbranched polyamide.

[0038] In the technical solution, the hyperbranched structure effectively fills the pores of the coating, enhances the compactness, and makes the coating remain intact after deformation to avoid the waterproof failure caused by the expansion of micropores.

[0039] In a second aspect, the application provides a preparation method of the above high-elasticity waterproof emulsion, comprising the following steps:

[0040] S1: uniformly mixing hydroxyethyl methacrylate, mercaptopropionic acid, a dynamic cross-linking agent and a solvent to obtain emulsion A;

[0041] S2: uniformly mixing a silicone emulsion and a fluorocarbon surfactant, heating to 35-45℃, and mixing for 10-15 min to obtain liquid B.

[0042] S3: add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide and part of defoaming agent into the reaction kettle, adjust pH to 5.0-5.5, heat to 55-65℃, react for 30-40min, add emulsion A, heat to 75-80℃, react for 70-80min, cool to 60-65℃, add fluorinated mica sheet, mix evenly, add liquid B, mix evenly, cool to 45-55℃, then add antioxidant, anti-aging agent and the rest of the defoaming agent, adjust pH to 7.5-8.0, get high-elastic waterproof emulsion.

[0043] Preferably, in step S3, after adipic acid dihydrazide, a step of adding castor oil polyester polyol is further included.

[0044] Preferably, in step S3, before adding antioxidant, a step of adding amino-terminated hyperbranched polyamide is further included.

[0045] In summary, the present application has the following beneficial effects:

[0046] The present application takes modified acrylic resin emulsion and water-based polyurethane as base material, realizes molecular-level compatibility through compatibilizer, builds a basic network with both hardness and toughness to provide mechanical performance skeleton for the coating; on this basis, the ketone group pre-embedded in the modified acrylic resin emulsion reacts with adipic acid dihydrazide to form a uniform and stable permanent crosslinking network, further strengthening the structural stability of the basic network; at the same time, by introducing a dynamic crosslinking agent to build a reversible bond network, a reversible-permanent double network is formed in cooperation with the permanent crosslinking network: the permanent network guarantees the morphological stability of the coating, and the dynamic network realizes energy absorption and micro-crack self-repairing through bond rupture-recombination during deformation, giving the coating high elasticity and self-repairing function; in addition, fluorinated mica sheet cooperates with silicone emulsion and fluorocarbon surfactant to build a gradient waterproof barrier, significantly improving the long-term impermeability of the coating. DETAILED DESCRIPTION

[0047] The present application is further described in detail below in conjunction with examples.

[0048] The raw materials of the examples and comparative examples of the present application are all ordinary commercial products unless otherwise specified.

[0049] Mica sheet, white, purity 99%, particle size distribution 10-40μm;

[0050] The number average molecular weight of castor oil polyester polyol is 2000-3000; the amine value of amino-terminated hyperbranched polyamide is 200-250mgKOH / g; the polydispersity index of styrene-butadiene-styrene block copolymer is 1.05-1.2; the polydispersity index of polyurethane acrylate is 1.5-3.0.

[0051] Preparation Example 1~3 fluorinated mica sheet

[0052] Preparation Example 1

[0053] The preparation method of the fluorinated mica sheet of the present preparation example comprises the following steps:

[0054] The mica sheet 100 g is laid on the plasma cabin loading plate, vacuumed to 10 Pa, argon is introduced at a flow rate of 50 sccm, the pressure is adjusted to 10 Pa, the radio frequency power supply is turned on with a power of 300 W, after 5 min of treatment, it is moved into the vapor phase reaction kettle, vacuumed to 10 Pa, -2 Pa, the temperature is raised to 140℃, liquid perfluorooctyl iodine 30 g is injected, 0.4 MPa is maintained, stirring and mixing are carried out at a rotation speed of 200 rpm for 180 min, it is reduced to 1 standard atmospheric pressure, the temperature is raised to 180℃, nitrogen blowing is carried out for 80 min, it is slowly cooled to 120℃, incubated for 30 min, then cooled to 80℃, incubated for 30 min, and then slowly cooled to room temperature to obtain the fluorinated mica sheet. - 3 Pa, the temperature is raised to 140℃, liquid perfluorooctyl iodine 30 g is injected, 0.4 MPa is maintained, stirring and mixing are carried out at a rotation speed of 200 rpm for 180 min, it is reduced to 1 standard atmospheric pressure, the temperature is raised to 180℃, nitrogen blowing is carried out for 80 min, it is slowly cooled to 120℃, incubated for 30 min, then cooled to 80℃, incubated for 30 min, and then slowly cooled to room temperature to obtain the fluorinated mica sheet.

[0055] Preparation Example 2

[0056] The preparation method of the fluorinated mica sheet of the present preparation example comprises the following steps:

[0057] The mica sheet 100 g is laid on the plasma cabin loading plate, vacuumed to 10 Pa, argon is introduced at a flow rate of 50 sccm, the pressure is adjusted to 10 Pa, the radio frequency power supply is turned on with a power of 300 W, after 5 min of treatment, it is moved into the vapor phase reaction kettle, vacuumed to 10 Pa, -2 Pa, the temperature is raised to 140℃, liquid perfluorooctyl iodine 30 g is injected, 0.4 MPa is maintained, stirring and mixing are carried out at a rotation speed of 200 rpm for 180 min, it is reduced to 1 standard atmospheric pressure, the temperature is raised to 180℃, nitrogen blowing is carried out for 80 min, it is slowly cooled to 120℃, incubated for 30 min, then cooled to 80℃, incubated for 30 min, and then slowly cooled to room temperature to obtain the fluorinated mica sheet. - 3 Pa, the temperature is raised to 140℃, liquid perfluorooctyl iodine 30 g is injected, 0.4 MPa is maintained, stirring and mixing are carried out at a rotation speed of 200 rpm for 180 min, it is reduced to 1 standard atmospheric pressure, the temperature is raised to 180℃, nitrogen blowing is carried out for 80 min, it is slowly cooled to 120℃, incubated for 30 min, then cooled to 80℃, incubated for 30 min, and then slowly cooled to room temperature to obtain the fluorinated mica sheet.

[0058] Preparation Example 3

[0059] The preparation method of the fluorinated mica sheet of the present preparation example comprises the following steps:

[0060] The mica sheet 100 g is laid on the plasma cabin loading plate, vacuumed to 10 Pa, argon is introduced at a flow rate of 50 sccm, the pressure is adjusted to 10 Pa, the radio frequency power supply is turned on with a power of 300 W, after 5 min of treatment, it is moved into the vapor phase reaction kettle, vacuumed to 10 Pa, -2 Pa, the temperature is raised to 140℃, liquid perfluorooctyl iodine 30 g is injected, 0.4 MPa is maintained, stirring and mixing are carried out at a rotation speed of 200 rpm for 180 min, it is reduced to 1 standard atmospheric pressure, the temperature is raised to 180℃, nitrogen blowing is carried out for 80 min, it is slowly cooled to 120℃, incubated for 30 min, then cooled to 80℃, incubated for 30 min, and then slowly cooled to room temperature to obtain the fluorinated mica sheet. - 3Pa, the temperature was raised to 140℃, liquid perfluorooctyl iodine 35g was injected, the mixture was stirred at 200rpm for 185min under 0.5MPa, the pressure was reduced to 1atm, the temperature was raised to 180℃, nitrogen was blown for 75min, the temperature was slowly cooled to 120℃, the temperature was kept for 30min, then the temperature was slowly cooled to 80℃, the temperature was kept for 30min, then the temperature was slowly cooled to room temperature, and fluorinated mica sheet was obtained.

[0061] Preparation of modified acrylic resin emulsion

[0062] Preparation Example 4

[0063] The preparation method of the modified acrylic resin emulsion of the present preparation example comprises the following steps:

[0064] S11: 100g of butyl acrylate, 20g of diacetone acrylamide, 10g of glycidyl methacrylate, 10g of vinyltrimethoxysilane and 2.8g of sodium dodecyl sulfate were added to 200mL of deionized water, and the mixture was stirred at 3000rpm for 15min to obtain a pre-emulsion;

[0065] S12: Under a nitrogen atmosphere, 1.0g of sodium dodecyl sulfate and 80mL of deionized water were added to a reaction kettle, the pH was adjusted to 5.0 with 10% citric acid, the temperature was raised to 75℃, one-third of the volume of the pre-emulsion and 0.8g of tert-butyl hydroperoxide, a formaldehyde sodium bisulfite solution (1.2g of formaldehyde sodium bisulfite and 5mL of deionized water mixed) were added, the mixture was stirred and mixed uniformly, and the temperature was kept for 40min. The remaining pre-emulsion, 1.3g of tert-butyl hydroperoxide and a formaldehyde sodium bisulfite solution (1.8g of formaldehyde sodium bisulfite and 10mL of deionized water mixed) were added, the temperature was kept for 80min, 0.2g of dodecyl mercaptan was added, the temperature was cooled to 60℃, the pH was adjusted to 7.5 with 10% ammonia water, the temperature was kept for 15min, 12g of fluorinated mica sheet was slowly added, and the mixture was stirred at 800rpm for 80min to obtain a modified acrylic resin emulsion.

[0066] The fluorinated mica sheet is from Preparation Example 1;

[0067] The solid content of the modified acrylic resin in the modified acrylic resin emulsion is 34.9%.

[0068] Preparation Example 5

[0069] The preparation method of the modified acrylic resin emulsion of the present preparation example comprises the following steps:

[0070] S11: 120 g of butyl acrylate, 30 g of diacetone acrylamide, 20 g of glycidyl methacrylate, 14 g of vinyl triethoxysilane, and 3.3 g of sodium dodecyl sulfate were added to 300 mL of deionized water, and stirred and mixed at a rotation speed of 3000 rpm for 30 min to obtain a pre-emulsion;

[0071] S12: Under a nitrogen atmosphere, 1.6 g of sodium dodecyl sulfate and 120 mL of deionized water were added to a reaction kettle, the pH was adjusted to 5.5 using 10% citric acid by mass, the temperature was raised to 85°C, one-third of the volume of the pre-emulsion and 1.0 g of t-butyl hydroperoxide, a formaldehyde sodium bisulfite solution (1.2 g of formaldehyde sodium bisulfite and 5 mL of deionized water mixed to form), were added, stirred and mixed uniformly, and incubated for 30 min. The remaining pre-emulsion and 1.7 g of t-butyl hydroperoxide, a formaldehyde sodium bisulfite solution (2.0 g of formaldehyde sodium bisulfite and 10 mL of deionized water mixed to form), were added, incubated for 60 min, 0.5 g of dodecyl mercaptan was added, incubated for 30 min, cooled to 55°C, the pH was adjusted to 8.0 using 10% ammonia water by mass, incubated for 25 min, 16 g of fluorinated mica flakes were slowly added, and stirred and mixed at 800 rpm for 100 min to obtain a modified acrylic resin emulsion.

[0072] In the modified acrylic resin emulsion, the solid content of the modified acrylic resin was 36.6%.

[0073] Preparation Example 6

[0074] The preparation method of the modified acrylic resin emulsion of the present preparation example comprises the following steps:

[0075] S11: 120 g of butyl acrylate, 30 g of diacetone acrylamide, 20 g of glycidyl methacrylate, 14 g of vinyl triethoxysilane, and 3.3 g of sodium dodecyl sulfate were added to 300 mL of deionized water, and stirred and mixed at a rotation speed of 3000 rpm for 30 min to obtain a pre-emulsion;

[0076] S12: Under the atmosphere of nitrogen, sodium dodecyl sulfate 1.2 g and 100 mL of deionized water were added into a reaction kettle, the pH was adjusted to 5.5 by using 10% citric acid, the temperature was raised to 80℃, one third of the volume of the pre-emulsion and tert-butyl hydroperoxide 1.3 g, formaldehyde sodium sulfite solution (formaldehyde sodium sulfite 1.2 g and deionized water 5 mL were mixed) were added, the mixture was stirred and mixed uniformly, and was kept for 35 min, the remaining pre-emulsion and tert-butyl hydroperoxide 2.0 g, formaldehyde sodium sulfite solution (formaldehyde sodium sulfite 2.4 g and deionized water 10 mL were mixed) were added, and was kept for 70 min, dodecyl mercaptan 0.4 g was added, and was kept for 35 min, the temperature was cooled to 65℃, the pH was adjusted to 7.5 by using 10% ammonia water, and was kept for 20 min, fluorinated mica sheet 14 g was slowly added, and the mixture was stirred and mixed at 800 rpm for 90 min, to obtain a modified acrylic resin emulsion.

[0077] The fluorinated mica sheet was prepared in Preparation Example 3.

[0078] In the modified acrylic resin emulsion, the solid content of the modified acrylic resin was 33.1%.

[0079] Example 1

[0080] The present example provides a high-elasticity waterproof emulsion prepared from the following raw materials:

[0081] The modified acrylic resin emulsion 40 g, the aqueous polyurethane 25 g, the hydroxyethyl methacrylate 3 g, the mercaptopropanoic acid 0.5 g, the fluorinated mica sheet 6 g, the silicone emulsion 3 g, the fluorocarbon surfactant 2 g, the adipic dihydrazide 0.8 g, the furfural 0.15 g, the N-hydroxyethyl maleimide 0.15 g, the compatibilizer 3 g, the antioxidant 0.5 g, the anti-aging agent 0.5 g, the defoaming agent 0.5 g, and the solvent 40 g.

[0082] The modified acrylic resin emulsion was prepared in Preparation Example 4, the aqueous polyurethane was the aqueous aliphatic anionic polyurethane dispersion Bayhydrol UH 2648 / 1, the fluorinated mica sheet was prepared in Preparation Example 1, the compatibilizer was styrene-butadiene-styrene block copolymer 1.5 g and polyurethane acrylate 1.5 g, the antioxidant was antioxidant 1010, the anti-aging agent was hindered amine stabilizer 144, the defoaming agent was polydimethylsiloxane, the silicone emulsion was Shin-Etsu KF-96L, the fluorocarbon surfactant was KF-3100, and in the solvent, the mass concentration of propylene glycol methyl ether was 10%, and the rest was deionized water.

[0083] The present example also provides a preparation method of the high-elasticity waterproof emulsion, comprising the following steps:

[0084] S1: stir and mix hydroxyethyl methacrylate, mercaptopropionic acid, furfural, N-hydroxyethyl maleimide and solvent according to the above ratio for 30 min to obtain emulsion A;

[0085] S2: uniformly mix silicone emulsion and fluorocarbon surfactant, warm to 35℃, continue to stir and mix for 15 min to obtain liquid B;

[0086] S3: add modified acrylic resin emulsion, waterborne polyurethane, compatibilizer, adipic acid dihydrazide and half of the mass of defoaming agent into a reaction kettle, adjust pH to 5.5 with 10% citric acid, warm to 55℃, react for 40 min, add emulsion A, dynamically adjust pH to about 5.5, warm to 75℃, react for 80 min, cool to 60℃, add fluorinated mica sheet, stir and mix at 500 rpm for 30 min, add liquid B, stir and mix at 500 rpm for 30 min, cool to 45℃, further add antioxidant, anti-aging agent and the remaining defoaming agent, adjust pH to 7.5 with 10% ammonia, pass through a 200 mesh sieve to obtain high-elasticity waterproof emulsion.

[0087] Example 2

[0088] The present embodiment provides a high-elasticity waterproof emulsion prepared from the following raw materials:

[0089] Modified acrylic resin emulsion 60g, waterborne polyurethane 40g, hydroxyethyl methacrylate 6g, mercaptopropionic acid 1g, fluorinated mica sheet 8g, silicone emulsion 6g, fluorocarbon surfactant 4g, adipic acid dihydrazide 1.5g, furfural 0.44g, N-hydroxyethyl maleimide 0.36g, compatibilizer 8g, antioxidant 1g, anti-aging agent 1g, defoaming agent 1g and solvent 55g.

[0090] The modified acrylic resin emulsion is from Preparation Example 5, the waterborne polyurethane is waterborne aliphatic anionic polyurethane dispersion Bayhydrol UH 2648 / 1; the fluorinated mica sheet is from Preparation Example 2; the compatibilizer is styrene-butadiene-styrene block copolymer 4g and polyurethane acrylate 4g; the antioxidant is antioxidant 1010, the anti-aging agent is hindered amine stabilizer 144, the defoaming agent is polydimethylsiloxane; the silicone emulsion is Shin-Etsu KF-96L; the fluorocarbon surfactant is KEMAMINE FS-3100; in the solvent, the mass concentration of propylene glycol methyl ether is 20%, and the rest is deionized water.

[0091] The present embodiment also provides a preparation method of the above high-elasticity waterproof emulsion, comprising the following steps:

[0092] S1: stir and mix hydroxyethyl methacrylate, mercaptopropionic acid, furfural, N-hydroxyethyl maleimide and solvent according to the above ratio for 40 min to obtain emulsion A;

[0093] S2: uniformly mix the silicone emulsion and fluorocarbon surfactant, heat to 45°C, continue to mix for 10 min, and obtain liquid B;

[0094] S3: add modified acrylic resin emulsion, waterborne polyurethane, compatibilizer, half of the mass of adipic acid dihydrazide and defoaming agent into a reaction kettle, adjust pH to 5.0 with 10% citric acid, heat to 65°C, react for 30 min, add emulsion A, dynamically adjust pH to about 5.0, heat to 80°C, react for 70 min, cool to 65°C, add fluorinated mica sheet, mix at 500 rpm for 40 min, add liquid B, mix at 500 rpm for 40 min, cool to 55°C, add antioxidant, anti-aging agent and the remaining defoaming agent, adjust pH to 8.0 with 10% ammonia, pass through a 200-mesh sieve, and obtain high-elastic waterproof emulsion.

[0095] Example 3

[0096] The present embodiment provides a high-elastic waterproof emulsion prepared from the following raw materials:

[0097] Modified acrylic resin emulsion 50 g, waterborne polyurethane 35 g, hydroxyethyl methacrylate 5 g, mercaptopropionic acid 0.8 g, fluorinated mica sheet 7 g, silicone emulsion 5 g, fluorocarbon surfactant 3 g, adipic acid dihydrazide 1 g, furfural 0.27 g, N-hydroxyethyl maleimide 0.33 g, compatibilizer 6 g, antioxidant 0.8 g, anti-aging agent 0.8 g, defoaming agent 0.8 g and solvent 50 g.

[0098] The modified acrylic resin emulsion is from Preparation Example 6, the waterborne polyurethane is waterborne aliphatic anionic polyurethane dispersion Bayhydrol UH 2648 / 1; the fluorinated mica sheet is from Preparation Example 3; the compatibilizer is styrene-butadiene-styrene block copolymer 3 g and polyurethane acrylate 3 g; the antioxidant is antioxidant 1010, the anti-aging agent is hindered amine stabilizer 144, the defoaming agent is polydimethylsiloxane; the silicone emulsion is Shin-Etsu KF-96L; the fluorocarbon surfactant is KEMFO FS-3100; and in the solvent, the mass concentration of propylene glycol methyl ether is 15%, and the rest is deionized water.

[0099] The present embodiment also provides a preparation method of the high-elastic waterproof emulsion, comprising the following steps:

[0100] S1: mix hydroxyethyl methacrylate, mercaptopropionic acid, furfural, N-hydroxyethyl maleimide and solvent according to the above proportions for 30 min to obtain emulsion A;

[0101] S2: the silicone emulsion, fluorocarbon surfactant is mixed uniformly, the temperature is raised to 40℃, and stirring is continuously mixed for 15 min, to obtain liquid B;

[0102] S3: the modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide, and half of the mass of defoaming agent are added into a reaction kettle, the pH is adjusted to 5.0 by using 10% citric acid, the temperature is raised to 60℃, and reaction is performed for 35 min, the emulsion A is added, the pH is dynamically adjusted to about 5.0, the temperature is raised to 80℃, and reaction is performed for 75 min, the temperature is lowered to 60℃, the fluorinated mica sheet is added, stirring is performed at 500 rpm for 40 min, the liquid B is added, stirring is performed at 500 rpm for 40 min, the temperature is lowered to 50℃, the antioxidant, anti-aging agent, and the remaining defoaming agent are added, the pH is adjusted to 8.0 by using 10% ammonia, and the high-elasticity waterproof emulsion is obtained by passing through a 200-mesh screen.

[0103] Example 4

[0104] The difference between the present example and Example 3 is that:

[0105] In step S3, after the adipic acid dihydrazide, a step of adding 1.5 g of castor oil polyester polyol is further included.

[0106] The rest is the same as Example 3.

[0107] Example 5

[0108] The difference between the present example and Example 4 is that:

[0109] The amount of castor oil polyester polyol is 3 g.

[0110] The rest is the same as Example 4.

[0111] Example 6

[0112] The difference between the present example and Example 5 is that:

[0113] S3: the modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide, castor oil polyester polyol, and half of the mass of defoaming agent are added into a reaction kettle, the pH is adjusted to 5.0 by using 10% citric acid, the temperature is raised to 60℃, and reaction is performed for 35 min, the emulsion A is added, the temperature is raised to 80℃, and reaction is performed for 75 min, the temperature is lowered to 60℃, the fluorinated mica sheet is added, stirring is performed at 500 rpm for 40 min, the liquid B is added, stirring is performed at 500 rpm for 40 min, the temperature is lowered to 50℃, the amino-terminated hyperbranched polyamide is added, stirring is performed for 10 min, the antioxidant, anti-aging agent, and the remaining defoaming agent are added, the pH is adjusted to 8.0 by using 10% ammonia, and the high-elasticity waterproof emulsion is obtained by passing through a 200-mesh screen.

[0114] The amount of the terminal amino hyperbranched polyamide is 2 g.

[0115] The other is the same as Example 5.

[0116] Example 7

[0117] The difference between this example and Example 6 is that:

[0118] The amount of the terminal amino hyperbranched polyamide is 5 g.

[0119] The other is the same as Example 6.

[0120] Comparative Example 1

[0121] The difference between this comparative example and Example 1 is that:

[0122] No adipic acid dihydrazide is added.

[0123] The other is the same as Example 1.

[0124] Comparative Example 2

[0125] The difference between this comparative example and Example 1 is that:

[0126] The preparation method of the modified acrylic resin emulsion comprises the following steps:

[0127] S11: 100 g of butyl acrylate, 10 g of glycidyl methacrylate, 10 g of vinyl trimethoxysilane and 2.8 g of sodium dodecyl sulfate are added to 200 mL of deionized water, stirred and mixed at a speed of 3000 rpm for 15 min to obtain a pre-emulsion;

[0128] S12: Under a nitrogen atmosphere, 1.0 g of sodium dodecyl sulfate and 80 mL of deionized water are added to a reaction kettle, the pH is adjusted to 5.5 with 10% citric acid by mass fraction, the temperature is raised to 75°C, one-third of the volume of the pre-emulsion and 0.8 g of tert-butyl hydroperoxide, a formaldehyde sodium bisulfite solution (1.2 g of formaldehyde sodium bisulfite and 5 mL of deionized water are mixed to form) are added, stirred and mixed uniformly, and kept at temperature for 40 min. The remaining pre-emulsion and 1.3 g of tert-butyl hydroperoxide, a formaldehyde sodium bisulfite solution (1.8 g of formaldehyde sodium bisulfite and 10 mL of deionized water are mixed to form) are added, kept at temperature for 80 min, 0.2 g of dodecyl mercaptan is added, kept at temperature for 40 min, cooled to 60°C, the pH is adjusted to 7.5 with 10% ammonia water by mass concentration, kept at temperature for 15 min, 12 g of fluorinated mica flakes are slowly added, and stirred and mixed at 800 rpm for 80 min to obtain a modified acrylic resin emulsion.

[0129] Comparative Example 3

[0130] The difference between this comparative example and Example 1 is that:

[0131] Mica flakes are used to replace fluorinated mica flakes. Before use, dry in a vacuum drying oven at a temperature of 80 DEG C until constant weight.

[0132] The other is the same as Example 1.

[0133] Comparative Example 4

[0134] The difference between this comparative example and Example 1 is that:

[0135] Hydroxyethyl methacrylate and mercaptopropionic acid are not added;

[0136] The other is the same as Example 1.

[0137] Comparative Example 5

[0138] The difference between this comparative example and Example 1 is that:

[0139] Furfural and N-hydroxyethyl maleimide are not added;

[0140] The other is the same as Example 1.

[0141] Performance test

[0142] The high-elastic waterproof emulsion prepared in Examples 1-7 and Comparative Examples 1-5 of the application was tested for performance according to "Polymer Emulsion Architectural Waterproof Coating" JC / T864-2023, and the results are shown in Tables 1 and 2.

[0143] Table 1 Performance test data of high-elastic waterproof emulsion prepared in Examples 1-7 and Comparative Examples 1-5

[0144]

[0145] Table 2 Performance test data of high-elastic waterproof emulsion prepared in Examples 1-7 and Comparative Examples 1-5

[0146]

[0147] From Example 1 and Comparative Examples 1-2, it can be seen that because adipic acid dihydrazide is not added or double acetone acrylamide is not added when the modified acrylic resin emulsion is prepared, the ketone hydrazine crosslinking system cannot be formed, the mechanical properties decrease, the compactness deteriorates, and the anti-aging performance decreases.

[0148] From Example 1 and Comparative Example 3, it can be seen that because fluorinated mica flakes are not used, the hydrophobicity and barrier property of the coating are greatly reduced, and the compatibility with the resin matrix is insufficient, resulting in slight precipitation.

[0149] From Example 1 and Comparative Example 4, it can be seen that because hydroxyethyl methacrylate and mercaptopropionic acid are not added, the uniformity of crosslinking and compactness of the coating are damaged, and micro-cracks are generated due to internal stress concentration.

[0150] From Example 1 and Comparative Example 5, it can be seen that: because furfural and N-hydroxyethyl maleimide are not added, the coating loses the reversible stress release mechanism, although its water impermeability and low temperature flexibility are good, but under repeated deformation, it cannot release stress through the breakage-recombination of reversible bonds, resulting in a decrease in elastic recovery ability.

[0151] From Examples 3-7, it can be seen that: because the castor oil polyester polyol is introduced, the dynamic cycle deformation recovery rate is further improved, the low temperature flexibility is stable, indicating that the long chain structure can long-term plasticize, improve the low temperature toughness and stress buffering capacity; the introduction of the amino-terminated hyperbranched polyamide further improves the strength retention rate after aging, enhances the bonding strength, and realizes the synergistic optimization of performance.

[0152] The specific embodiments are merely an explanation of the present application, which is not a limitation of the present application, and those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A highly elastic waterproof emulsion, characterized in that, It is prepared from the following raw materials in parts by weight: 40-60 parts modified acrylic resin emulsion, 25-40 parts waterborne polyurethane, 3-6 parts hydroxyethyl methacrylate, 0.5-1 part mercaptopropionic acid, 6-8 parts fluorinated mica sheets, 3-6 parts organosilicon emulsion, 2-4 parts fluorocarbon surfactant, 0.8-1.5 parts adipic acid dihydrazide, 0.3-0.8 parts dynamic crosslinking agent, 3-8 parts compatibilizer, 0.5-1 part antioxidant, 0.5-1 part anti-aging agent, 0.5-1.5 parts defoamer, and 40-55 parts solvent; The modified acrylic resin emulsion is prepared from the following raw materials in parts by weight: 50-70 parts butyl acrylate, 10-20 parts diacetone acrylamide, 5-15 parts glycidyl methacrylate, and 5-8 parts organosilicon containing double bonds.

2. The high-elasticity waterproof emulsion according to claim 1, characterized in that, The dynamic crosslinking agent includes furfural and N-hydroxyethyl maleimide.

3. The high-elasticity waterproof emulsion according to claim 1, characterized in that, The preparation method of the modified acrylic resin emulsion, by weight, includes the following steps: S11: Add 50-70 parts of butyl acrylate, 10-20 parts of diacetone acrylamide, 5-15 parts of glycidyl methacrylate, 5-8 parts of organosilicon containing double bonds and some emulsifier to water, mix evenly to obtain a pre-emulsion; S12: Under an inert atmosphere, add the remaining emulsifier and water to the reactor, adjust the pH to 5.0~5.5, heat to 75~85℃, add part of the pre-emulsion and part of the initiator, keep warm for 30~40min, add the remaining pre-emulsion and the remaining initiator, keep warm for 60~80min, add dodecyl mercaptan, keep warm for 30~40min, cool to 55~65℃, adjust the pH to 7.5~8.0, add 6~8 parts of fluorinated mica sheets, mix for 80~100min to obtain the modified acrylic resin emulsion.

4. The high-elasticity waterproof emulsion according to claim 1, characterized in that, The method for preparing the fluorinated mica sheet includes the following steps: After plasma activation of mica sheets, they are placed in a gas-phase reactor and heated to 135-140°C. Liquid perfluoroalkyl iodine is injected and maintained at 0.4-0.5 MPa. The mixture is stirred for 180-190 min, the pressure is reduced, the temperature is raised to 180-185°C, nitrogen is purged for 70-80 min, and then cooled to obtain fluorinated mica sheets.

5. The high-elasticity waterproof emulsion according to claim 1, characterized in that, The high-elasticity waterproof emulsion also includes 1.5 to 3 parts by weight of castor oil polyester polyol.

6. The high-elasticity waterproof emulsion according to claim 1, characterized in that, The high-elasticity waterproof emulsion also includes 2-5 parts by weight of amino-terminated hyperbranched polyamide.

7. A method for preparing a highly elastic waterproof emulsion as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1: Hydroxyethyl methacrylate, mercaptopropionic acid, dynamic crosslinking agent and solvent are mixed evenly to obtain emulsion A; S2: Mix the silicone emulsion and fluorocarbon surfactant evenly, heat to 35~45℃, mix for 10~15 min to obtain liquid B; S3: Add the modified acrylic resin emulsion, waterborne polyurethane, compatibilizer, adipic acid dihydrazide, and part of the defoamer to the reactor, adjust the pH to 5.0~5.5, raise the temperature to 55~65℃, react for 30~40 min, add emulsion A, and raise the temperature to 75~80℃. React for 70-80 minutes, cool to 60-65℃, add fluorinated mica sheets, mix well, add liquid B, mix well, cool to 45-55℃, then add antioxidant, anti-aging agent and the remaining defoamer, adjust pH to 7.5-8.0, and obtain a high-elasticity waterproof emulsion.

8. The method for preparing the high-elasticity waterproof emulsion according to claim 7, characterized in that, In step S3, after adipic acid dihydrazide, the step of adding castor oil polyester polyol is also included.

9. The method for preparing the high-elasticity waterproof emulsion according to claim 7, characterized in that, In step S3, before adding the antioxidant, the step of adding terminal amino hyperbranched polyamide is also included.

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