High-elasticity waterproof emulsion and preparation method thereof

Abstract

The invention relates to the technical field of waterproof materials, and particularly discloses a high-elasticity waterproof emulsion and a preparation method thereof. The invention discloses a high-elasticity waterproof emulsion. The water-based paint is prepared from the following raw materials in parts by mass: 40 to 60 parts of modified acrylic resin emulsion, 25 to 40 parts of waterborne polyurethane, 3 to 6 parts of hydroxyethyl methylacrylate, 0.5 to 1 part of mercaptopropionic acid, 6 to 8 parts of fluorinated mica sheet, 3 to 6 parts of organic silicon emulsion, 2 to 4 parts of fluorocarbon surfactant, 0.8 to 1.5 parts of adipic dihydrazide, 0.3 to 0.8 part of dynamic cross-linking agent, 3 to 8 parts of compatilizer, 0.5 to 1 part of antioxidant, 0.5 to 1 part of anti-aging agent, 0.5 to 1.5 parts of defoaming agent and 40 to 55 parts of solvent. The modified acrylic resin emulsion is prepared from a monomer comprising diacetone acrylamide. The high-elasticity waterproof emulsion prepared by the invention has relatively good elasticity, waterproof performance and aging resistance.

Description

Technical Field

[0001] The present application relates to the technical field of waterproof materials, and more specifically, to a high-elastic waterproof emulsion and a preparation method thereof. Background Art

[0002] As a core material for building waterproofing projects, the core value of elastic waterproof emulsions lies in their ability to dynamically adapt to substrate deformation through the flexible design of polymer chains and the regulation of network structures, thereby blocking water penetration pathways. Common elastic waterproof emulsions can be divided into three categories based on the type of base polymer: polymer emulsion waterproof emulsions, polyurethane waterproof emulsions, and acrylic waterproof emulsions. While each of these three types of emulsions has its own advantages, they still face common challenges in practical application: such as the long-term elasticity retention of polymer emulsions, the low-temperature application performance of polyurethane emulsions, and the dynamic crack resistance of acrylic resin emulsions. These technical pain points are also driving the continuous innovation of elastic waterproof emulsions towards "higher elasticity, better weather resistance, and wider adaptability."

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

[0004] In this technical solution, the base material system based on acrylic emulsion is cross-linked only by diacetone acrylamide and adipic dihydrazide. This single rigid cross-linking structure makes it difficult for the coating to release stress under repeated deformation and prone to permanent deformation; gelatin will absorb environmental moisture, causing the coating to absorb water and expand, destroying the density and causing microcracks inside the coating. Although glycerol, as a small molecule plasticizer, can temporarily enhance the initial flexibility, it easily migrates to the coating surface over time, causing the coating to gradually harden and become brittle, and more prone to cracking under low temperature or high-frequency deformation. Summary of the Invention

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

[0006] In a first aspect, the present application provides a high-elastic waterproof emulsion, which adopts the following technical solution: A high-elastic waterproof emulsion is prepared by including the following raw materials in parts by weight: 40-60 parts of modified acrylic resin emulsion, 25-40 parts of waterborne polyurethane, 3-6 parts of hydroxyethyl methacrylate, 0.5-1 part of mercaptopropionic acid, 6-8 parts of fluorinated mica flakes, 3-6 parts of silicone emulsion, 2-4 parts of fluorocarbon surfactant, 0.8-1.5 parts of adipic acid dihydrazide, 0.3-0.8 parts of dynamic crosslinking agent, 3-8 parts of compatibilizer, 0.5-1 part of antioxidant, 0.5-1 part of anti-aging agent, 0.5-1.5 parts of defoaming agent, and 40-55 parts of solvent; The modified acrylic resin emulsion is prepared from monomers including diacetone acrylamide.

[0007] In this technical solution, modified acrylic resin emulsion and water-based polyurethane are used as base materials. The two are compatible at the molecular level through a compatibilizer to avoid phase separation, effectively improve the elongation at break of the coating, and can also effectively resist physical damage such as scratches and collisions. Fluorinated mica flakes are oriented at the bottom of the coating by virtue of their flaky structure to form a physical barrier layer. The surface layer is formed by the migration of silicone emulsion and fluorocarbon surfactant components to form a low surface energy hydrophobic film, constructing a gradient waterproof structure to effectively block the invasion of moisture and corrosive media; at the same time, the ketone groups pre-embedded in the modified acrylic resin emulsion can form a stable and uniform cross-linked network when subsequently reacting with adipic acid dihydrazide; a dynamic cross-linking agent is simultaneously compounded to construct a reversible bond network. The two work together to form a reversible-permanent double network structure. The permanent network maintains the morphological stability of the coating, and the dynamic network breaks to absorb energy and reorganizes to repair microcracks during deformation, giving the coating high elasticity and self-healing properties.

[0008] Preferably, the solid content of the modified acrylic resin emulsion is about 33% to 36.5%.

[0009] Preferably, the compatibilizer comprises styrene-butadiene-styrene block copolymer and polyurethane acrylate.

[0010] Preferably, the dynamic cross-linking agent includes furfural and N-hydroxyethylmaleimide.

[0011] Preferably, the mass ratio of furfural and N-hydroxyethylmaleimide is 1:(0.8-1.2).

[0012] Preferably, the antioxidant includes antioxidant 1010.

[0013] Preferably, the antioxidant further includes antioxidant 168.

[0014] Preferably, the antioxidant is hindered amine stabilizer 144.

[0015] Preferably, the defoaming agent is polydimethylsiloxane.

[0016] Preferably, the solvent includes water and propylene glycol methyl ether.

[0017] Preferably, in the solvent, the mass concentration of propylene glycol methyl ether is 10% to 20%, and the rest is water.

[0018] Preferably, the modified acrylic resin emulsion is mainly prepared from the following raw materials in parts by weight: 50-70 parts of butyl acrylate, 10-20 parts of diacetone acrylamide, 5-15 parts of glycidyl methacrylate, and 5-8 parts of double-bond silicone.

[0019] Preferably, the raw materials of the modified acrylic resin emulsion further include 6 to 8 parts by mass of fluorinated mica flakes.

[0020] Preferably, the preparation method of the modified acrylic resin emulsion comprises the following steps, calculated by mass: S11: adding 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 part of the emulsifier to water, and mixing uniformly 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, raise the temperature to 75-85°C, add part of the pre-emulsion and part of the initiator, keep warm for 30-40 minutes, add the remaining pre-emulsion and the remaining initiator, keep warm for 60-80 minutes, add dodecyl mercaptan, keep warm for 30-40 minutes, cool to 55-65°C, adjust the pH to 7.5-8.0, add 6-8 parts of fluorinated mica flakes, mix for 80-100 minutes, and obtain a modified acrylic resin emulsion.

[0021] Preferably, the organosilicon containing double bonds is any one of vinyltrimethoxysilane and vinyltriethoxysilane.

[0022] In this technical solution, butyl acrylate provides flexible segments, diacetone acrylamide and adipic acid dihydrazide form pre-crosslinking points, and glycidyl methacrylate reacts with active groups in the waterborne polyurethane to enhance interfacial bonding. Double-bonded organosilicon hydrolyzes to form siloxane segments, improving both the compatibility of the resin with the waterborne polyurethane and the weather resistance of the coating. Fluorinated mica flakes are pre-dispersed during the resin synthesis stage to enhance the mechanical strength and barrier properties of the subsequent coating, ensuring that the resulting resin film possesses both toughness and impermeability.

[0023] Preferably, the amount of the emulsifier used is 2.7% to 4.4% of the total mass of butyl acrylate, diacetone acrylamide, glycidyl methacrylate and double-bond-containing silicone.

[0024] Preferably, the initiator comprises tert-butyl hydroperoxide and sodium formaldehyde sulfoxylate.

[0025] Preferably, the amount of the initiator is 2.6% to 3.8% of the total mass of butyl acrylate, diacetone acrylamide, glycidyl methacrylate and double-bond-containing organosilicon.

[0026] Preferably, the method for preparing the fluorinated mica sheet comprises the following steps: After plasma activation, the mica sheet is placed in a gas phase reactor, heated to 135-140°C, injected with liquid perfluoroalkyl iodide, maintained at 0.4-0.5 MPa, mixed for 180-190 minutes, depressurized, heated to 180-185°C, purged with nitrogen for 70-80 minutes, and cooled to obtain fluorinated mica sheets.

[0027] Preferably, the mass ratio of the mica flakes to perfluoroalkyl iodide is 1:(0.3-0.4).

[0028] In this technical solution, perfluoroalkyl iodide vapor-phase fluorination imparts both hydrophobicity and flaky barrier properties to mica flakes. Once oriented within the coating, they form a multi-layer physical barrier, extending the water permeation path and effectively improving the coating's water resistance. The flaky structure disperses frictional stress, while the fluorinated surface reduces the coefficient of friction, improving adhesion to the substrate and preventing flake shedding during wear.

[0029] Preferably, the high-elastic waterproof emulsion further comprises 1.5 to 3 parts by mass of castor oil polyester polyol.

[0030] In this technical solution: castor oil polyester polyol is bonded and cross-linked and embedded in the polyurethane network, and its long alkyl chain provides continuous molecular segment movement ability, thereby enhancing the elasticity retention rate of the coating at low temperatures.

[0031] Preferably, the high-elastic waterproof emulsion further comprises 2 to 5 parts by mass of amino-terminated hyperbranched polyamide.

[0032] In this technical solution, the hyperbranched structure effectively fills the pores of the coating, enhances the density, and enables the coating to remain intact after deformation, thereby avoiding waterproof failure caused by the expansion of micropores.

[0033] In a second aspect, the present application provides a method for preparing the above-mentioned high-elastic waterproof emulsion, comprising the following steps: S1: Mix hydroxyethyl methacrylate, mercaptopropionic acid, a dynamic crosslinking agent and a solvent to obtain emulsion A; S2: Mix the silicone emulsion and fluorocarbon surfactant evenly, heat to 35-45°C, and mix for 10-15 minutes to obtain Liquid B; S3: Add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide and part of the defoaming agent into the reactor, adjust the 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 flakes, mix evenly, add liquid B, mix evenly, cool to 45~55℃, add antioxidant, antioxidant and the remaining defoaming agent, adjust the pH to 7.5~8.0, and obtain a high-elastic waterproof emulsion.

[0034] Preferably, in step S3, after adipic acid dihydrazide, the step of adding castor oil polyester polyol is further included.

[0035] Preferably, in step S3, before adding the antioxidant, the step of adding amino-terminated hyperbranched polyamide is also included.

[0036] In summary, this application has the following beneficial effects: This application uses modified acrylic resin emulsion and water-based polyurethane as the base materials, achieves molecular-level compatibility through a compatibilizer, and constructs a basic network with both hardness and toughness to provide a mechanical performance skeleton for the coating; on this basis, the ketone groups pre-embedded in the modified acrylic resin emulsion react with adipic acid dihydrazide to form a uniform and stable permanent cross-linked network, further enhancing the structural stability of the basic network; at the same time, a reversible bond network is constructed by introducing a dynamic cross-linking agent, which cooperates with the permanent cross-linked network to form a reversible-permanent double network: the permanent network ensures the morphological stability of the coating, and the dynamic network achieves energy absorption and microcrack self-repair through bond breaking and recombination during deformation, giving the coating high elasticity and self-repairing function; in addition, fluorinated mica sheets work synergistically with silicone emulsion and fluorocarbon surfactants to construct a gradient waterproof barrier, significantly improving the long-term anti-seepage performance of the coating. DETAILED DESCRIPTION

[0037] The present application is further described in detail below with reference to the embodiments.

[0038] Unless otherwise specified, the raw materials used in the examples and comparative examples of the present application are all commercially available.

[0039] Mica flakes, white, 99% purity, particle size distribution 10~40μm; 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; and the polydispersity index of polyurethane acrylate is 1.5~3.0.

[0040] Preparation Examples 1-3 Fluorinated Mica Sheets Preparation Example 1 The preparation method of the fluorinated mica sheet of this preparation example comprises the following steps: Spread 100g of mica sheet on the plasma chamber carrier plate and evacuate to 10 -2 Pa, introduce argon with a flow rate of 50 sccm, adjust the pressure to 10Pa, turn on the RF power supply with a power of 300W, treat for 5 minutes, move into the gas phase reactor, and evacuate to 10 - 3 Pa, heat to 140 ° C, inject 30 g of liquid perfluorooctyl iodide, maintain 0.4 MPa, stir and mix at a speed of 200 rpm for 180 minutes, reduce to 1 standard atmospheric pressure, heat to 180 ° C, purge with nitrogen for 80 minutes, slowly cool to 120 ° C, keep warm for 30 minutes, then cool to 80 ° C, keep warm for 30 minutes, and then slowly cool to room temperature to obtain fluorinated mica sheets.

[0041] Preparation Example 2 The preparation method of the fluorinated mica sheet of this preparation example comprises the following steps: Spread 100g of mica sheet on the plasma chamber carrier plate and evacuate to 10 -2 Pa, introduce argon with a flow rate of 50 sccm, adjust the pressure to 10Pa, turn on the RF power supply with a power of 300W, and after treating for 6 minutes, move it into the gas phase reactor and evacuate to 10 - 3 Pa, heat to 135 ° C, inject 40 g of liquid perfluorooctyl iodide, maintain 0.5 MPa, stir and mix at a speed of 200 rpm for 190 minutes, reduce to 1 standard atmospheric pressure, heat to 185 ° C, purge with nitrogen for 70 minutes, slowly cool to 120 ° C, keep warm for 30 minutes, then cool to 80 ° C, keep warm for 30 minutes, and then slowly cool to room temperature to obtain fluorinated mica sheets.

[0042] Preparation Example 3 The preparation method of the fluorinated mica sheet of this preparation example comprises the following steps: Spread 100g of mica sheet on the plasma chamber carrier plate and evacuate to 10 -2 Pa, introduce argon with a flow rate of 50 sccm, adjust the pressure to 10Pa, turn on the RF power supply with a power of 300W, treat for 5 minutes, move into the gas phase reactor, and evacuate to 10 - 3 Pa, heat to 140 ° C, inject 35 g of liquid perfluorooctyl iodide, maintain 0.5 MPa, stir and mix at a speed of 200 rpm for 185 minutes, reduce to 1 standard atmospheric pressure, heat to 180 ° C, purge with nitrogen for 75 minutes, slowly cool to 120 ° C, keep warm for 30 minutes, then cool to 80 ° C, keep warm for 30 minutes, and then slowly cool to room temperature to obtain fluorinated mica sheets.

[0043] Preparation Examples 4-6 Modified Acrylic Resin Emulsion Preparation Example 4 The preparation method of the modified acrylic resin emulsion of this preparation example comprises the following steps: S11: 100 g of butyl acrylate, 20 g of diacetone acrylamide, 10 g of glycidyl methacrylate, 10 g of vinyltrimethoxysilane, and 2.8 g of sodium lauryl sulfate were added to 200 mL of deionized water, and the mixture was stirred at 3000 rpm for 15 min to obtain a pre-emulsion; S12: Under a nitrogen atmosphere, 1.0 g of sodium dodecyl sulfate and 80 mL of deionized water were added to a reactor, and the pH was adjusted to 5.0 with 10% citric acid. The temperature was raised to 75°C, and one-third of the volume of the pre-emulsion and 0.8 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (mixed with 1.2 g of sodium formaldehyde sulfoxylate and 5 mL of deionized water) were added. The mixture was stirred and mixed evenly, and the mixture was kept warm for 40 minutes. The remaining pre-emulsion and 1.3 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (mixed with 1.8 g of sodium formaldehyde sulfoxylate and 10 mL of deionized water) were added. The mixture was kept warm for 80 minutes. 0.2 g of dodecyl mercaptan was added and the mixture was kept warm for 40 minutes. The mixture was cooled to 60°C, and the pH was adjusted to 7.5 with 10% ammonia water. The mixture was kept warm for 15 minutes. 12 g of fluorinated mica flakes were slowly added, and the mixture was stirred and mixed at 800 rpm for 80 minutes to obtain a modified acrylic resin emulsion.

[0044] Wherein, the fluorinated mica flakes are from Preparation Example 1; In the modified acrylic resin emulsion, the solid content of the modified acrylic resin is 34.9%.

[0045] Preparation Example 5 The preparation method of the modified acrylic resin emulsion of this preparation example comprises the following steps: S11: 140 g of butyl acrylate, 40 g of diacetone acrylamide, 30 g of glycidyl methacrylate, 16 g of vinyl triethoxysilane, and 4.5 g of sodium lauryl sulfate were added to 300 mL of deionized water, and the mixture was stirred at 3000 rpm for 30 min to obtain a pre-emulsion; S12: Under a nitrogen atmosphere, 1.6 g of sodium dodecyl sulfate and 120 mL of deionized water were added to a reactor, and the pH was adjusted to 5.5 with 10% by mass of citric acid. The temperature was raised to 85°C, and one-third of the volume of the pre-emulsion and 1.0 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (mixed with 1.2 g of sodium formaldehyde sulfoxylate and 5 mL of deionized water) were added. The mixture was stirred and mixed evenly, and the mixture was kept warm for 30 minutes. The remaining pre-emulsion and 1.7 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (mixed with 2.0 g of sodium formaldehyde sulfoxylate and 10 mL of deionized water) were added. The mixture was kept warm for 60 minutes. 0.5 g of dodecyl mercaptan was added, and the mixture was kept warm for 30 minutes. The mixture was cooled to 55°C, and the pH was adjusted to 8.0 with 10% by mass of ammonia water. The mixture was kept warm for 25 minutes. 16 g of fluorinated mica flakes were slowly added, and the mixture was stirred and mixed at 800 rpm for 100 minutes to obtain a modified acrylic resin emulsion.

[0046] The fluorinated mica flakes are from Preparation Example 2; and the solid content of the modified acrylic resin in the modified acrylic resin emulsion is 36.6%.

[0047] Preparation Example 6 The preparation method of the modified acrylic resin emulsion of this preparation example comprises the following steps: 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 lauryl sulfate were added to 300 mL of deionized water, and the mixture was stirred at 3000 rpm for 30 min to obtain a pre-emulsion; S12: Under a nitrogen atmosphere, 1.2 g of sodium lauryl sulfate and 100 mL of deionized water were added to a reactor, and the pH was adjusted to 5.5 with 10% by mass of citric acid. The temperature was raised to 80°C, and one-third of the volume of the pre-emulsion and 1.3 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (a mixture of 1.2 g of sodium formaldehyde sulfoxylate and 5 mL of deionized water) were added. The mixture was stirred and mixed evenly, and the mixture was kept warm for 35 minutes. The remaining pre-emulsion and 2.0 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (a mixture of 2.4 g of sodium formaldehyde sulfoxylate and 10 mL of deionized water) were added. The mixture was kept warm for 70 minutes. 0.4 g of dodecyl mercaptan was added, and the mixture was kept warm for 35 minutes. The mixture was cooled to 65°C, and the pH was adjusted to 7.5 with 10% by mass of ammonia water. The mixture was kept warm for 20 minutes. 14 g of fluorinated mica flakes were slowly added, and the mixture was stirred and mixed at 800 rpm for 90 minutes to obtain a modified acrylic resin emulsion.

[0048] Among them, the fluorinated mica flakes are from Preparation Example 3; In the modified acrylic resin emulsion, the solid content of the modified acrylic resin is 33.1%.

[0049] Example 1 This embodiment provides a high-elastic waterproof emulsion, which is prepared from the following raw materials: 40g modified acrylic resin emulsion, 25g water-based polyurethane, 3g hydroxyethyl methacrylate, 0.5g mercaptopropionic acid, 6g fluorinated mica flakes, 3g silicone emulsion, 2g fluorocarbon surfactant, 0.8g adipic acid dihydrazide, 0.15g furfural, 0.15g N-hydroxyethylmaleimide, 3g compatibilizer, 0.5g antioxidant, 0.5g antioxidant, 0.5g defoaming agent and 40g solvent.

[0050] Among them, the modified acrylic resin emulsion is from Preparation Example 4, the water-based polyurethane is the water-based aliphatic anionic polyurethane dispersion Bayhydrol UH 2648 / 1; the fluorinated mica flakes are from Preparation Example 1; the compatibilizers are 1.5 g of styrene-butadiene-styrene block copolymer and 1.5 g of polyurethane acrylate; the antioxidant is antioxidant 1010, the antioxidant is hindered amine stabilizer 144, and the defoaming agent is polydimethylsiloxane; the silicone emulsion is Shin-Etsu KF-96L; the fluorocarbon surfactant is Chemours FS-3100; in the solvent, the mass concentration of propylene glycol methyl ether is 10%, and the rest is deionized water.

[0051] This embodiment also provides a method for preparing the above-mentioned high-elastic waterproof emulsion, comprising the following steps: S1: hydroxyethyl methacrylate, mercaptopropionic acid, furfural, N-hydroxyethylmaleimide and solvent were stirred and mixed according to the above ratio for 30 minutes to obtain emulsion A; S2: Mix the silicone emulsion and fluorocarbon surfactant evenly, raise the temperature to 35°C, and continue stirring for 15 minutes to obtain Liquid B; S3: Add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide and half of the defoaming agent into the reactor, adjust the pH to 5.5 with 10% by mass of citric acid, raise the temperature to 55°C, react for 40 minutes, add emulsion A, dynamically adjust the pH to about 5.5, raise the temperature to 75°C, react for 80 minutes, cool to 60°C, add fluorinated mica flakes, stir and mix at 500 rpm for 30 minutes, add liquid B, stir and mix at 500 rpm for 30 minutes, cool to 45°C, add antioxidant, antioxidant and the remaining defoaming agent, adjust the pH to 7.5 with 10% by mass of ammonia water, pass through a 200-mesh sieve to obtain a high-elastic waterproof emulsion.

[0052] Example 2 This embodiment provides a high-elastic waterproof emulsion, which is prepared from the following raw materials: 60g modified acrylic resin emulsion, 40g water-based polyurethane, 6g hydroxyethyl methacrylate, 1g mercaptopropionic acid, 8g fluorinated mica flakes, 6g silicone emulsion, 4g fluorocarbon surfactant, 1.5g adipic acid dihydrazide, 0.44g furfural, 0.36g N-hydroxyethylmaleimide, 8g compatibilizer, 1g antioxidant, 1g anti-aging agent, 1g defoaming agent and 55g solvent.

[0053] Among them, the modified acrylic resin emulsion is from Preparation Example 5, the water-based polyurethane is the water-based aliphatic anionic polyurethane dispersion Bayhydrol UH 2648 / 1; the fluorinated mica flakes are from Preparation Example 2; the compatibilizers are 4 g of styrene-butadiene-styrene block copolymer and 4 g of polyurethane acrylate; the antioxidant is antioxidant 1010, the antioxidant is hindered amine stabilizer 144, and the defoaming agent is polydimethylsiloxane; the silicone emulsion is Shin-Etsu KF-96L; the fluorocarbon surfactant is Chemours FS-3100; in the solvent, the mass concentration of propylene glycol methyl ether is 20%, and the rest is deionized water.

[0054] This embodiment also provides a method for preparing the above-mentioned high-elastic waterproof emulsion, comprising the following steps: S1: hydroxyethyl methacrylate, mercaptopropionic acid, furfural, N-hydroxyethylmaleimide and solvent were stirred and mixed according to the above ratio for 40 minutes to obtain emulsion A; S2: Mix the organosilicon emulsion and fluorocarbon surfactant evenly, raise the temperature to 45°C, and continue stirring for 10 minutes to obtain Liquid B; S3: Add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide and half of the defoaming agent into the reactor, adjust the pH to 5.0 with 10% by mass of citric acid, heat to 65°C, react for 30 minutes, add emulsion A, dynamically adjust the pH to about 5.0, heat to 80°C, react for 70 minutes, cool to 65°C, add fluorinated mica flakes, stir and mix at 500 rpm for 40 minutes, add liquid B, stir and mix at 500 rpm for 40 minutes, cool to 55°C, add antioxidant, antioxidant and the remaining defoaming agent, adjust the pH to 8.0 with 10% by mass of ammonia water, pass through a 200-mesh sieve to obtain a high-elastic waterproof emulsion.

[0055] Example 3 This embodiment provides a high-elastic waterproof emulsion, which is prepared from the following raw materials: 50g modified acrylic resin emulsion, 35g water-based polyurethane, 5g hydroxyethyl methacrylate, 0.8g mercaptopropionic acid, 7g fluorinated mica flakes, 5g silicone emulsion, 3g fluorocarbon surfactant, 1g adipic acid dihydrazide, 0.27g furfural, 0.33g N-hydroxyethylmaleimide, 6g compatibilizer, 0.8g antioxidant, 0.8g antioxidant, 0.8g defoaming agent and 50g solvent.

[0056] Among them, the modified acrylic resin emulsion is from Preparation Example 6, the water-based polyurethane is the water-based aliphatic anionic polyurethane dispersion Bayhydrol UH 2648 / 1; the fluorinated mica flakes are from Preparation Example 3; the compatibilizers are 3 g of styrene-butadiene-styrene block copolymer and 3 g of polyurethane acrylate; the antioxidant is antioxidant 1010, the antioxidant is hindered amine stabilizer 144, and the defoaming agent is polydimethylsiloxane; the silicone emulsion is Shin-Etsu KF-96L; the fluorocarbon surfactant is Chemours FS-3100; in the solvent, the mass concentration of propylene glycol methyl ether is 15%, and the rest is deionized water.

[0057] This embodiment also provides a method for preparing the above-mentioned high-elastic waterproof emulsion, comprising the following steps: S1: hydroxyethyl methacrylate, mercaptopropionic acid, furfural, N-hydroxyethylmaleimide and solvent were stirred and mixed according to the above ratio for 30 minutes to obtain emulsion A; S2: Mix the organosilicon emulsion and fluorocarbon surfactant evenly, raise the temperature to 40°C, and continue stirring for 15 minutes to obtain Liquid B; S3: Add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide and half of the defoaming agent into the reactor, adjust the pH to 5.0 with 10% by mass of citric acid, raise the temperature to 60°C, react for 35 minutes, add emulsion A, dynamically adjust the pH to about 5.0, raise the temperature to 80°C, react for 75 minutes, cool to 60°C, add fluorinated mica flakes, stir and mix at 500 rpm for 40 minutes, add liquid B, stir and mix at 500 rpm for 40 minutes, cool to 50°C, add antioxidant, antioxidant and the remaining defoaming agent, adjust the pH to 8.0 with 10% by mass of ammonia water, pass through a 200-mesh sieve to obtain a high-elastic waterproof emulsion.

[0058] Example 4 The difference between this embodiment and embodiment 3 is that: In step S3, after adipic acid dihydrazide, 1.5 g of castor oil polyester polyol is added.

[0059] Other details are the same as in Example 3.

[0060] Example 5 The difference between this embodiment and embodiment 4 is that: The amount of castor oil polyester polyol used is 3g.

[0061] Other details are the same as in Example 4.

[0062] Example 6 The difference between this embodiment and embodiment 5 is that: S3: Add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide, castor oil polyester polyol and half of the defoaming agent into the reactor, adjust the pH to 5.0 with 10% by mass of citric acid, raise the temperature to 60°C, react for 35 minutes, add emulsion A, raise the temperature to 80°C, react for 75 minutes, cool to 60°C, add fluorinated mica flakes, stir and mix at 500 rpm for 40 minutes, add liquid B, stir and mix at 500 rpm for 40 minutes, cool to 50°C, add amino-terminated hyperbranched polyamide, stir and mix for 10 minutes, then add antioxidant, antioxidant and the remaining defoaming agent, adjust the pH to 8.0 with 10% by mass of ammonia water, pass through a 200-mesh sieve to obtain a high-elastic waterproof emulsion.

[0063] Wherein, the amount of amino-terminated hyperbranched polyamide is 2 g.

[0064] Other details are the same as in Example 5.

[0065] Example 7 The difference between this embodiment and embodiment 6 is that: The amount of amino-terminated hyperbranched polyamide is 5 g; Other details are the same as in Example 6.

[0066] Comparative Example 1 The difference between this comparative example and Example 1 is: Adipic acid dihydrazide is not added; Other details are the same as in Example 1.

[0067] Comparative Example 2 The difference between this comparative example and Example 1 is: The preparation method of the modified acrylic resin emulsion comprises the following steps: S11: 100 g of butyl acrylate, 10 g of glycidyl methacrylate, 10 g of vinyltrimethoxysilane, and 2.8 g of sodium lauryl sulfate were added to 200 mL of deionized water, and the mixture was stirred at 3000 rpm for 15 min to obtain a pre-emulsion; S12: Under a nitrogen atmosphere, 1.0 g of sodium dodecyl sulfate and 80 mL of deionized water were added to a reactor, and the pH was adjusted to 5.5 with 10% by mass of citric acid. The temperature was raised to 75°C, and one-third of the volume of the pre-emulsion and 0.8 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (mixed with 1.2 g of sodium formaldehyde sulfoxylate and 5 mL of deionized water) were added. The mixture was stirred and mixed evenly, and the mixture was kept warm for 40 minutes. The remaining pre-emulsion and 1.3 g of tert-butyl hydroperoxide and a sodium formaldehyde sulfoxylate solution (mixed with 1.8 g of sodium formaldehyde sulfoxylate and 10 mL of deionized water) were added. The mixture was kept warm for 80 minutes. 0.2 g of dodecyl mercaptan was added, and the mixture was kept warm for 40 minutes. The mixture was cooled to 60°C, and the pH was adjusted to 7.5 with 10% by mass of ammonia water. The mixture was kept warm for 15 minutes. 12 g of fluorinated mica flakes were slowly added, and the mixture was stirred and mixed at 800 rpm for 80 minutes to obtain a modified acrylic resin emulsion.

[0068] Comparative Example 3 The difference between this comparative example and Example 1 is: Mica sheets were used to replace the fluorinated mica sheets and were dried to constant weight at 80°C in a vacuum drying oven before use.

[0069] Other details are the same as in Example 1.

[0070] Comparative Example 4 The difference between this comparative example and Example 1 is: No hydroxyethyl methacrylate and mercaptopropionic acid were added; Other details are the same as in Example 1.

[0071] Comparative Example 5 The difference between this comparative example and Example 1 is: Furfural and N-hydroxyethylmaleimide were not added; Other details are the same as in Example 1.

[0072] Performance Testing The performance of the high-elastic waterproof emulsions prepared in Examples 1 to 7 and Comparative Examples 1 to 5 of the present application was tested in accordance with JC / T864-2023 "Polymer Emulsion Building Waterproof Coatings". The results are shown in Tables 1 and 2.

[0073] Table 1 Performance test data of the high elastic waterproof emulsion prepared in Examples 1 to 7 and Comparative Examples 1 to 5

[0074] Table 2 Performance test data of the high elastic waterproof emulsion prepared in Examples 1 to 7 and Comparative Examples 1 to 5

[0075] It can be seen from Example 1 and Comparative Examples 1-2 that due to the lack of addition of adipic acid dihydrazide or the lack of addition of diacetone acrylamide in the modified acrylic resin emulsion, the ketone hydrazide crosslinking system cannot be formed, the mechanical properties are reduced, the density is deteriorated, and the anti-aging performance is reduced.

[0076] It can be seen from Example 1 and Comparative Example 3 that: due to the lack of the use of fluorinated mica sheets, the hydrophobicity and barrier properties of the coating are greatly reduced, and the compatibility with the resin matrix is ​​insufficient, resulting in slight precipitation.

[0077] It can be seen from Example 1 and Comparative Example 4 that due to the absence of hydroxyethyl methacrylate and mercaptopropionic acid, the crosslinking uniformity and density of the coating are impaired, and internal stress concentration causes microcracks to initiate.

[0078] It can be seen from Example 1 and Comparative Example 5 that: due to the lack of furfural and N-hydroxyethylmaleimide, the coating loses its reversible stress release mechanism. Although it has good impermeability and low-temperature flexibility, it cannot release stress through the breaking and recombination of reversible bonds under repeated deformation, resulting in a decrease in elastic recovery ability.

[0079] As can be seen from Examples 3 to 7, the introduction of castor oil polyester polyol further improves the dynamic cyclic deformation recovery rate and maintains stable low-temperature flexibility, indicating that its long-chain structure can provide long-term plasticization, thereby improving low-temperature toughness and stress buffering capacity. The introduction of amino-terminated hyperbranched polyamide further improves the strength retention rate after aging and enhances the bonding strength, achieving synergistic optimization of performance.

[0080] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A high elastic waterproof emulsion, characterized in that: The invention is prepared by comprising the following raw materials in parts by weight: 40-60 parts of modified acrylic resin emulsion, 25-40 parts of waterborne polyurethane, 3-6 parts of hydroxyethyl methacrylate, 0.5-1 part of mercaptopropionic acid, 6-8 parts of fluorinated mica flakes, 3-6 parts of silicone emulsion, 2-4 parts of fluorocarbon surfactant, 0.8-1.5 parts of adipic acid dihydrazide, 0.3-0.8 parts of dynamic crosslinking agent, 3-8 parts of compatibilizer, 0.5-1 part of antioxidant, 0.5-1 part of anti-aging agent, 0.5-1.5 parts of defoaming agent and 40-55 parts of solvent; The modified acrylic resin emulsion is prepared from monomers including diacetone acrylamide.

2. The high-elastic waterproof emulsion according to claim 1, characterized in that: The dynamic cross-linking agent includes furfural and N-hydroxyethylmaleimide.

3. The high elastic waterproof emulsion according to claim 1, characterized in that: The modified acrylic resin emulsion is mainly prepared from the following raw materials in parts by weight: 50-70 parts of butyl acrylate, 10-20 parts of diacetone acrylamide, 5-15 parts of glycidyl methacrylate, and 5-8 parts of double-bond silicone.

4. The high-elastic waterproof emulsion according to claim 1, characterized in that: The preparation method of the modified acrylic resin emulsion comprises the following steps, calculated by weight: S11: adding 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 part of the emulsifier to water, and mixing uniformly 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, raise the temperature to 75-85°C, add part of the pre-emulsion and part of the initiator, keep warm for 30-40 minutes, add the remaining pre-emulsion and the remaining initiator, keep warm for 60-80 minutes, add dodecyl mercaptan, keep warm for 30-40 minutes, cool to 55-65°C, adjust the pH to 7.5-8.0, add 6-8 parts of fluorinated mica flakes, mix for 80-100 minutes, and obtain a modified acrylic resin emulsion.

5. The high-elastic waterproof emulsion according to claim 1, characterized in that: The preparation method of the fluorinated mica sheet comprises the following steps: After plasma activation, the mica sheet is placed in a gas phase reactor, heated to 135-140°C, injected with liquid perfluoroalkyl iodide, maintained at 0.4-0.5 MPa, mixed for 180-190 minutes, depressurized, heated to 180-185°C, purged with nitrogen for 70-80 minutes, and cooled to obtain fluorinated mica sheets.

6. The high-elastic waterproof emulsion according to claim 1, characterized in that: The high-elastic waterproof emulsion further comprises 1.5 to 3 parts by mass of castor oil polyester polyol.

7. The high-elastic waterproof emulsion according to claim 1, characterized in that: The high-elastic waterproof emulsion further comprises 2 to 5 parts by mass of amino-terminated hyperbranched polyamide.

8. A method for preparing the high-elastic waterproof emulsion according to any one of claims 1 to 7, characterized in that: The steps include: S1: Mix hydroxyethyl methacrylate, mercaptopropionic acid, a dynamic crosslinking agent and a solvent to obtain emulsion A; S2: Mix the silicone emulsion and fluorocarbon surfactant evenly, heat to 35-45°C, and mix for 10-15 minutes to obtain Liquid B; S3: Add modified acrylic resin emulsion, water-based polyurethane, compatibilizer, adipic acid dihydrazide and part of the defoaming agent into the reactor, adjust the 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 flakes, mix evenly, add liquid B, mix evenly, cool to 45~55℃, add antioxidant, antioxidant and the remaining defoaming agent, adjust the pH to 7.5~8.0, and obtain a high-elastic waterproof emulsion.

9. The method for preparing the high-elastic waterproof emulsion according to claim 8, characterized in that: In step S3, after adipic acid dihydrazide, castor oil polyester polyol is added.

10. The method for preparing the high-elastic waterproof emulsion according to claim 8, characterized in that: In step S3, before adding the antioxidant, the step of adding amino-terminated hyperbranched polyamide is also included.

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